Commit Graph

670 Commits

Author SHA1 Message Date
Thomas Gleixner
b4d0d230cc treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public licence as published by
  the free software foundation either version 2 of the licence or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 114 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170857.552531963@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:11 +02:00
David Howells
2e21865faf keys: sparse: Fix key_fs[ug]id_changed()
Sparse warnings are incurred by key_fs[ug]id_changed() due to unprotected
accesses of tsk->cred, which is marked __rcu.

Fix this by passing the new cred struct to these functions from
commit_creds() rather than the task pointer.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
2019-05-22 14:06:51 +01:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Linus Torvalds
78ee8b1b9b Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "Just a few bugfixes and documentation updates"

* 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  seccomp: fix up grammar in comment
  Revert "security: inode: fix a missing check for securityfs_create_file"
  Yama: mark function as static
  security: inode: fix a missing check for securityfs_create_file
  keys: safe concurrent user->{session,uid}_keyring access
  security: don't use RCU accessors for cred->session_keyring
  Yama: mark local symbols as static
  LSM: lsm_hooks.h: fix documentation format
  LSM: fix documentation for the shm_* hooks
  LSM: fix documentation for the sem_* hooks
  LSM: fix documentation for the msg_queue_* hooks
  LSM: fix documentation for the audit_* hooks
  LSM: fix documentation for the path_chmod hook
  LSM: fix documentation for the socket_getpeersec_dgram hook
  LSM: fix documentation for the task_setscheduler hook
  LSM: fix documentation for the socket_post_create hook
  LSM: fix documentation for the syslog hook
  LSM: fix documentation for sb_copy_data hook
2019-05-07 08:39:54 -07:00
Linus Torvalds
81ff5d2cba Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "API:
   - Add support for AEAD in simd
   - Add fuzz testing to testmgr
   - Add panic_on_fail module parameter to testmgr
   - Use per-CPU struct instead multiple variables in scompress
   - Change verify API for akcipher

  Algorithms:
   - Convert x86 AEAD algorithms over to simd
   - Forbid 2-key 3DES in FIPS mode
   - Add EC-RDSA (GOST 34.10) algorithm

  Drivers:
   - Set output IV with ctr-aes in crypto4xx
   - Set output IV in rockchip
   - Fix potential length overflow with hashing in sun4i-ss
   - Fix computation error with ctr in vmx
   - Add SM4 protected keys support in ccree
   - Remove long-broken mxc-scc driver
   - Add rfc4106(gcm(aes)) cipher support in cavium/nitrox"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (179 commits)
  crypto: ccree - use a proper le32 type for le32 val
  crypto: ccree - remove set but not used variable 'du_size'
  crypto: ccree - Make cc_sec_disable static
  crypto: ccree - fix spelling mistake "protedcted" -> "protected"
  crypto: caam/qi2 - generate hash keys in-place
  crypto: caam/qi2 - fix DMA mapping of stack memory
  crypto: caam/qi2 - fix zero-length buffer DMA mapping
  crypto: stm32/cryp - update to return iv_out
  crypto: stm32/cryp - remove request mutex protection
  crypto: stm32/cryp - add weak key check for DES
  crypto: atmel - remove set but not used variable 'alg_name'
  crypto: picoxcell - Use dev_get_drvdata()
  crypto: crypto4xx - get rid of redundant using_sd variable
  crypto: crypto4xx - use sync skcipher for fallback
  crypto: crypto4xx - fix cfb and ofb "overran dst buffer" issues
  crypto: crypto4xx - fix ctr-aes missing output IV
  crypto: ecrdsa - select ASN1 and OID_REGISTRY for EC-RDSA
  crypto: ux500 - use ccflags-y instead of CFLAGS_<basename>.o
  crypto: ccree - handle tee fips error during power management resume
  crypto: ccree - add function to handle cryptocell tee fips error
  ...
2019-05-06 20:15:06 -07:00
Eric Biggers
877b5691f2 crypto: shash - remove shash_desc::flags
The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.

With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP.  These would all need to be fixed if any shash algorithm
actually started sleeping.  For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API.  However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.

Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk.  It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.

Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-25 15:38:12 +08:00
Jann Horn
0b9dc6c9f0 keys: safe concurrent user->{session,uid}_keyring access
The current code can perform concurrent updates and reads on
user->session_keyring and user->uid_keyring. Add a comment to
struct user_struct to document the nontrivial locking semantics, and use
READ_ONCE() for unlocked readers and smp_store_release() for writers to
prevent memory ordering issues.

Fixes: 69664cf16a ("keys: don't generate user and user session keyrings unless they're accessed")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-04-10 10:29:50 -07:00
Jann Horn
5c7e372caa security: don't use RCU accessors for cred->session_keyring
sparse complains that a bunch of places in kernel/cred.c access
cred->session_keyring without the RCU helpers required by the __rcu
annotation.

cred->session_keyring is written in the following places:

 - prepare_kernel_cred() [in a new cred struct]
 - keyctl_session_to_parent() [in a new cred struct]
 - prepare_creds [in a new cred struct, via memcpy]
 - install_session_keyring_to_cred()
  - from install_session_keyring() on new creds
  - from join_session_keyring() on new creds [twice]
  - from umh_keys_init()
   - from call_usermodehelper_exec_async() on new creds

All of these writes are before the creds are committed; therefore,
cred->session_keyring doesn't need RCU protection.

Remove the __rcu annotation and fix up all existing users that use __rcu.

Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-04-10 10:28:21 -07:00
ndesaulniers@google.com
be24b37e22 KEYS: trusted: fix -Wvarags warning
Fixes the warning reported by Clang:
security/keys/trusted.c:146:17: warning: passing an object that
undergoes default
      argument promotion to 'va_start' has undefined behavior [-Wvarargs]
        va_start(argp, h3);
                       ^
security/keys/trusted.c:126:37: note: parameter of type 'unsigned
char' is declared here
unsigned char *h2, unsigned char h3, ...)
                               ^
Specifically, it seems that both the C90 (4.8.1.1) and C11 (7.16.1.4)
standards explicitly call this out as undefined behavior:

The parameter parmN is the identifier of the rightmost parameter in
the variable parameter list in the function definition (the one just
before the ...). If the parameter parmN is declared with ... or with a
type that is not compatible with the type that results after
application of the default argument promotions, the behavior is
undefined.

Link: https://github.com/ClangBuiltLinux/linux/issues/41
Link: https://www.eskimo.com/~scs/cclass/int/sx11c.html
Suggested-by: David Laight <David.Laight@aculab.com>
Suggested-by: Denis Kenzior <denkenz@gmail.com>
Suggested-by: James Bottomley <jejb@linux.vnet.ibm.com>
Suggested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-04-08 15:58:54 -07:00
Jarkko Sakkinen
c78719203f KEYS: trusted: allow trusted.ko to initialize w/o a TPM
Allow trusted.ko to initialize w/o a TPM. This commit also adds checks
to the exported functions to fail when a TPM is not available.

Fixes: 240730437d ("KEYS: trusted: explicitly use tpm_chip structure...")
Cc: James Morris <jmorris@namei.org>
Reported-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-04-08 15:58:53 -07:00
Linus Torvalds
5af7f11588 Merge branch 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull tpm updates from James Morris:

 - Clean up the transmission flow

   Cleaned up the whole transmission flow. Locking of the chip is now
   done in the level of tpm_try_get_ops() and tpm_put_ops() instead
   taking the chip lock inside tpm_transmit(). The nested calls inside
   tpm_transmit(), used with the resource manager, have been refactored
   out.

   Should make easier to perform more complex transactions with the TPM
   without making the subsystem a bigger mess (e.g. encrypted channel
   patches by James Bottomley).

 - PPI 1.3 support

   TPM PPI 1.3 introduces an additional optional command parameter that
   may be needed for some commands. Display the parameter if the command
   requires such a parameter. Only command 23 (SetPCRBanks) needs one.

   The PPI request file will show output like this then:

      # echo "23 16" > request
      # cat request
      23 16

      # echo "5" > request
      # cat request
      5

 - Extend all PCR banks in IMA

   Instead of static PCR banks array, the array of available PCR banks
   is now allocated dynamically. The digests sizes are determined
   dynamically using a probe PCR read without relying crypto's static
   list of hash algorithms.

   This should finally make sealing of measurements in IMA safe and
   secure.

 - TPM 2.0 selftests

   Added a test suite to tools/testing/selftests/tpm2 previously outside
   of the kernel tree: https://github.com/jsakkine-intel/tpm2-scripts

* 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (37 commits)
  tpm/ppi: Enable submission of optional command parameter for PPI 1.3
  tpm/ppi: Possibly show command parameter if TPM PPI 1.3 is used
  tpm/ppi: Display up to 101 operations as define for version 1.3
  tpm/ppi: rename TPM_PPI_REVISION_ID to TPM_PPI_REVISION_ID_1
  tpm/ppi: pass function revision ID to tpm_eval_dsm()
  tpm: pass an array of tpm_extend_digest structures to tpm_pcr_extend()
  KEYS: trusted: explicitly use tpm_chip structure from tpm_default_chip()
  tpm: move tpm_chip definition to include/linux/tpm.h
  tpm: retrieve digest size of unknown algorithms with PCR read
  tpm: rename and export tpm2_digest and tpm2_algorithms
  tpm: dynamically allocate the allocated_banks array
  tpm: remove @flags from tpm_transmit()
  tpm: take TPM chip power gating out of tpm_transmit()
  tpm: introduce tpm_chip_start() and tpm_chip_stop()
  tpm: remove TPM_TRANSMIT_UNLOCKED flag
  tpm: use tpm_try_get_ops() in tpm-sysfs.c.
  tpm: remove @space from tpm_transmit()
  tpm: move TPM space code out of tpm_transmit()
  tpm: move tpm_validate_commmand() to tpm2-space.c
  tpm: clean up tpm_try_transmit() error handling flow
  ...
2019-03-10 17:37:29 -07:00
Linus Torvalds
c3665a6be5 Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull integrity updates from James Morris:
 "Mimi Zohar says:

   'Linux 5.0 introduced the platform keyring to allow verifying the IMA
    kexec kernel image signature using the pre-boot keys. This pull
    request similarly makes keys on the platform keyring accessible for
    verifying the PE kernel image signature.

    Also included in this pull request is a new IMA hook that tags tmp
    files, in policy, indicating the file hash needs to be calculated.
    The remaining patches are cleanup'"

* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  evm: Use defined constant for UUID representation
  ima: define ima_post_create_tmpfile() hook and add missing call
  evm: remove set but not used variable 'xattr'
  encrypted-keys: fix Opt_err/Opt_error = -1
  kexec, KEYS: Make use of platform keyring for signature verify
  integrity, KEYS: add a reference to platform keyring
2019-03-10 17:32:04 -07:00
Linus Torvalds
ae5906ceee Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:

 - Extend LSM stacking to allow sharing of cred, file, ipc, inode, and
   task blobs. This paves the way for more full-featured LSMs to be
   merged, and is specifically aimed at LandLock and SARA LSMs. This
   work is from Casey and Kees.

 - There's a new LSM from Micah Morton: "SafeSetID gates the setid
   family of syscalls to restrict UID/GID transitions from a given
   UID/GID to only those approved by a system-wide whitelist." This
   feature is currently shipping in ChromeOS.

* 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (62 commits)
  keys: fix missing __user in KEYCTL_PKEY_QUERY
  LSM: Update list of SECURITYFS users in Kconfig
  LSM: Ignore "security=" when "lsm=" is specified
  LSM: Update function documentation for cap_capable
  security: mark expected switch fall-throughs and add a missing break
  tomoyo: Bump version.
  LSM: fix return value check in safesetid_init_securityfs()
  LSM: SafeSetID: add selftest
  LSM: SafeSetID: remove unused include
  LSM: SafeSetID: 'depend' on CONFIG_SECURITY
  LSM: Add 'name' field for SafeSetID in DEFINE_LSM
  LSM: add SafeSetID module that gates setid calls
  LSM: add SafeSetID module that gates setid calls
  tomoyo: Allow multiple use_group lines.
  tomoyo: Coding style fix.
  tomoyo: Swicth from cred->security to task_struct->security.
  security: keys: annotate implicit fall throughs
  security: keys: annotate implicit fall throughs
  security: keys: annotate implicit fall through
  capabilities:: annotate implicit fall through
  ...
2019-03-07 11:44:01 -08:00
Ben Dooks
468e91cecb keys: fix missing __user in KEYCTL_PKEY_QUERY
The arg5 of KEYCTL_PKEY_QUERY should have a __user pointer tag on
it as it is a user pointer. This clears the following sparse warning
for this:

security/keys/keyctl.c:1755:43: warning: incorrect type in argument 3 (different address spaces)
security/keys/keyctl.c:1755:43:    expected struct keyctl_pkey_query [noderef] <asn:1>*<noident>
security/keys/keyctl.c:1755:43:    got struct keyctl_pkey_query *<noident>

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-03-04 15:48:37 -08:00
Eric Biggers
ede0fa98a9 KEYS: always initialize keyring_index_key::desc_len
syzbot hit the 'BUG_ON(index_key->desc_len == 0);' in __key_link_begin()
called from construct_alloc_key() during sys_request_key(), because the
length of the key description was never calculated.

The problem is that we rely on ->desc_len being initialized by
search_process_keyrings(), specifically by search_nested_keyrings().
But, if the process isn't subscribed to any keyrings that never happens.

Fix it by always initializing keyring_index_key::desc_len as soon as the
description is set, like we already do in some places.

The following program reproduces the BUG_ON() when it's run as root and
no session keyring has been installed.  If it doesn't work, try removing
pam_keyinit.so from /etc/pam.d/login and rebooting.

    #include <stdlib.h>
    #include <unistd.h>
    #include <keyutils.h>

    int main(void)
    {
            int id = add_key("keyring", "syz", NULL, 0, KEY_SPEC_USER_KEYRING);

            keyctl_setperm(id, KEY_OTH_WRITE);
            setreuid(5000, 5000);
            request_key("user", "desc", "", id);
    }

Reported-by: syzbot+ec24e95ea483de0a24da@syzkaller.appspotmail.com
Fixes: b2a4df200d ("KEYS: Expand the capacity of a keyring")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-02-22 10:11:34 -08:00
David Howells
7c1857bdbd keys: Timestamp new keys
Set the timestamp on new keys rather than leaving it unset.

Fixes: 31d5a79d7f ("KEYS: Do LRU discard in full keyrings")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-02-15 14:12:09 -08:00
David Howells
822ad64d7e keys: Fix dependency loop between construction record and auth key
In the request_key() upcall mechanism there's a dependency loop by which if
a key type driver overrides the ->request_key hook and the userspace side
manages to lose the authorisation key, the auth key and the internal
construction record (struct key_construction) can keep each other pinned.

Fix this by the following changes:

 (1) Killing off the construction record and using the auth key instead.

 (2) Including the operation name in the auth key payload and making the
     payload available outside of security/keys/.

 (3) The ->request_key hook is given the authkey instead of the cons
     record and operation name.

Changes (2) and (3) allow the auth key to naturally be cleaned up if the
keyring it is in is destroyed or cleared or the auth key is unlinked.

Fixes: 7ee02a316600 ("keys: Fix dependency loop between construction record and auth key")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-02-15 14:12:09 -08:00
Eric Biggers
a08bf91ce2 KEYS: allow reaching the keys quotas exactly
If the sysctl 'kernel.keys.maxkeys' is set to some number n, then
actually users can only add up to 'n - 1' keys.  Likewise for
'kernel.keys.maxbytes' and the root_* versions of these sysctls.  But
these sysctls are apparently supposed to be *maximums*, as per their
names and all documentation I could find -- the keyrings(7) man page,
Documentation/security/keys/core.rst, and all the mentions of EDQUOT
meaning that the key quota was *exceeded* (as opposed to reached).

Thus, fix the code to allow reaching the quotas exactly.

Fixes: 0b77f5bfb4 ("keys: make the keyring quotas controllable through /proc/sys")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-02-15 14:12:08 -08:00
Roberto Sassu
0b6cf6b97b tpm: pass an array of tpm_extend_digest structures to tpm_pcr_extend()
Currently, tpm_pcr_extend() accepts as an input only a SHA1 digest.

This patch replaces the hash parameter of tpm_pcr_extend() with an array of
tpm_digest structures, so that the caller can provide a digest for each PCR
bank currently allocated in the TPM.

tpm_pcr_extend() will not extend banks for which no digest was provided,
as it happened before this patch, but instead it requires that callers
provide the full set of digests. Since the number of digests will always be
chip->nr_allocated_banks, the count parameter has been removed.

Due to the API change, ima_pcr_extend() and pcrlock() have been modified.
Since the number of allocated banks is not known in advance, the memory for
the digests must be dynamically allocated. To avoid performance degradation
and to avoid that a PCR extend is not done due to lack of memory, the array
of tpm_digest structures is allocated by the users of the TPM driver at
initialization time.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Mimi Zohar <zohar@linux.ibm.com> (on x86 for TPM 1.2 & PTT TPM 2.0)
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2019-02-13 09:48:52 +02:00
Roberto Sassu
240730437d KEYS: trusted: explicitly use tpm_chip structure from tpm_default_chip()
When crypto agility support will be added to the TPM driver, users of the
driver have to retrieve the allocated banks from chip->allocated_banks and
use this information to prepare the array of tpm_digest structures to be
passed to tpm_pcr_extend().

This patch retrieves a tpm_chip pointer from tpm_default_chip() so that the
pointer can be used to prepare the array of tpm_digest structures.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2019-02-13 09:48:51 +02:00
Mimi Zohar
107dfa2e56 encrypted-keys: fix Opt_err/Opt_error = -1
Properly start the enumeration associated with match_table_t at zero,
making Opt_err/Opt_error the last enumeration value.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-02-04 17:36:01 -05:00
Mathieu Malaterre
23711df7f4 security: keys: annotate implicit fall throughs
There is a plan to build the kernel with -Wimplicit-fallthrough and
these places in the code produced warnings (W=1). Fix them up.

This commit remove the following warnings:

  security/keys/request_key.c:293:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
  security/keys/request_key.c:298:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
  security/keys/request_key.c:307:7: warning: this statement may fall through [-Wimplicit-fallthrough=]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-01-22 19:47:47 -08:00
Mathieu Malaterre
0f949bcc7b security: keys: annotate implicit fall throughs
There is a plan to build the kernel with -Wimplicit-fallthrough and
these places in the code produced warnings (W=1). Fix them up.

This commit remove the following warning:

  security/keys/process_keys.c:380:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
  security/keys/process_keys.c:404:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
  security/keys/process_keys.c:424:7: warning: this statement may fall through [-Wimplicit-fallthrough=]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-01-22 19:47:47 -08:00
Mathieu Malaterre
5b73262a5c security: keys: annotate implicit fall through
There is a plan to build the kernel with -Wimplicit-fallthrough and
this place in the code produced a warning (W=1).

This commit remove the following warning:

  security/keys/keyring.c:248:10: warning: this statement may fall through [-Wimplicit-fallthrough=]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-01-22 19:47:47 -08:00
Eric Biggers
57b0e31453 KEYS: fix parsing invalid pkey info string
We need to check the return value of match_token() for Opt_err before
doing anything with it.

[ Not only did the old "-1" value for Opt_err cause problems for the
  __test_and_set_bit(), as fixed in commit 94c13f66e1 ("security:
  don't use a negative Opt_err token index"), but accessing
  "args[0].from" is invalid for the Opt_err case, as pointed out by Eric
  later.  - Linus ]

Reported-by: syzbot+a22e0dc07567662c50bc@syzkaller.appspotmail.com
Fixes: 00d60fd3b9 ("KEYS: Provide keyctls to drive the new key type ops for asymmetric keys [ver #2]")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: stable@kernel.org # 4.20
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-01 13:13:19 -08:00
Linus Torvalds
75f95da078 libnvdimm for 4.21
* Add support for the security features of nvdimm devices that
   implement a security model similar to ATA hard drive security. The
   security model supports locking access to the media at
   device-power-loss, to be unlocked with a passphrase, and secure-erase
   (crypto-scramble).
 
   Unlike the ATA security case where the kernel expects device
   security to be managed in a pre-OS environment, the libnvdimm security
   implementation allows key provisioning and key-operations at OS
   runtime. Keys are managed with the kernel's encrypted-keys facility to
   provide data-at-rest security for the libnvdimm key material. The
   usage model mirrors fscrypt key management, but is driven via
   libnvdimm sysfs.
 
 * Miscellaneous updates for api usage and comment fixes.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJcJalaAAoJEB7SkWpmfYgCmpkP/35Isou2xxbYdICt9HR4WjiE
 E4r66Ck+ivZW4oEAub3RQw/SwcZePjuHArO5MgVGFoM1dBMABE+JvKiZm1xybCil
 iuWT/V7ozlNf5LuvacvjUXe/suUIoqji9yzLEEx9mDaISehrYvvy579DFxkE8Aww
 8Vcx8E1DQkXiWY4d9nmDmAjt8GQPNmsdHfTwMcJg7XSywTkURF64vW7/94aN8QtV
 rH5ZKKOra8Lqn0S05RoH4XegZcE6TZxgE23ZXsobBJrWdbGVFmgbz6AaewJc/+QU
 ZW3dx/1NAe7Op25xewJOjdG/Kl0gzWtqCrHCu8LeaSjwtHsgMQ/FBhL9g/7GRtHt
 hcQy12Iu9YTn3FOl8yfNRKb7lE5/1nJ2MtW8Z55WKHONHzN9cgrZLOwmpTYgrR/r
 SmIzwKNFavLwwz9bj+paHhmTngLDnNbvR6FwAKwSbWinotbLEyfMhU1jJ9RmHxSV
 M+jqS1BJ9IvH+WVN5bVa7oCNpVeq6yMw0Ow2vWXMPbiwh17ShACI59paqZKRiR06
 WH8SgdTPOZuMndtQV+m8zFBiJtmgAtGSiN8c1A/1QZJHDTpXz2MdWhtx5McvFsZ9
 Jot4Vd8mFWI7oVLdb+PF/AGZnKNAnD8PdsAlFws0k7+rM6lf6gf5n/CkjjMuSapG
 Q/kf0cOpPq8wdsrnOzyc
 =7KYd
 -----END PGP SIGNATURE-----

Merge tag 'libnvdimm-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "The vast bulk of this update is the new support for the security
  capabilities of some nvdimms.

  The userspace tooling for this capability is still a work in progress,
  but the changes survive the existing libnvdimm unit tests. The changes
  also pass manual checkout on hardware and the new nfit_test emulation
  of the security capability.

  The touches of the security/keys/ files have received the necessary
  acks from Mimi and David. Those changes were necessary to allow for a
  new generic encrypted-key type, and allow the nvdimm sub-system to
  lookup key material referenced by the libnvdimm-sysfs interface.

  Summary:

   - Add support for the security features of nvdimm devices that
     implement a security model similar to ATA hard drive security. The
     security model supports locking access to the media at
     device-power-loss, to be unlocked with a passphrase, and
     secure-erase (crypto-scramble).

     Unlike the ATA security case where the kernel expects device
     security to be managed in a pre-OS environment, the libnvdimm
     security implementation allows key provisioning and key-operations
     at OS runtime. Keys are managed with the kernel's encrypted-keys
     facility to provide data-at-rest security for the libnvdimm key
     material. The usage model mirrors fscrypt key management, but is
     driven via libnvdimm sysfs.

   - Miscellaneous updates for api usage and comment fixes"

* tag 'libnvdimm-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (21 commits)
  libnvdimm/security: Quiet security operations
  libnvdimm/security: Add documentation for nvdimm security support
  tools/testing/nvdimm: add Intel DSM 1.8 support for nfit_test
  tools/testing/nvdimm: Add overwrite support for nfit_test
  tools/testing/nvdimm: Add test support for Intel nvdimm security DSMs
  acpi/nfit, libnvdimm/security: add Intel DSM 1.8 master passphrase support
  acpi/nfit, libnvdimm/security: Add security DSM overwrite support
  acpi/nfit, libnvdimm: Add support for issue secure erase DSM to Intel nvdimm
  acpi/nfit, libnvdimm: Add enable/update passphrase support for Intel nvdimms
  acpi/nfit, libnvdimm: Add disable passphrase support to Intel nvdimm.
  acpi/nfit, libnvdimm: Add unlock of nvdimm support for Intel DIMMs
  acpi/nfit, libnvdimm: Add freeze security support to Intel nvdimm
  acpi/nfit, libnvdimm: Introduce nvdimm_security_ops
  keys-encrypted: add nvdimm key format type to encrypted keys
  keys: Export lookup_user_key to external users
  acpi/nfit, libnvdimm: Store dimm id as a member to struct nvdimm
  libnvdimm, namespace: Replace kmemdup() with kstrndup()
  libnvdimm, label: Switch to bitmap_zalloc()
  ACPI/nfit: Adjust annotation for why return 0 if fail to find NFIT at start
  libnvdimm, bus: Check id immediately following ida_simple_get
  ...
2018-12-28 15:05:13 -08:00
Linus Torvalds
b71acb0e37 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "API:
   - Add 1472-byte test to tcrypt for IPsec
   - Reintroduced crypto stats interface with numerous changes
   - Support incremental algorithm dumps

  Algorithms:
   - Add xchacha12/20
   - Add nhpoly1305
   - Add adiantum
   - Add streebog hash
   - Mark cts(cbc(aes)) as FIPS allowed

  Drivers:
   - Improve performance of arm64/chacha20
   - Improve performance of x86/chacha20
   - Add NEON-accelerated nhpoly1305
   - Add SSE2 accelerated nhpoly1305
   - Add AVX2 accelerated nhpoly1305
   - Add support for 192/256-bit keys in gcmaes AVX
   - Add SG support in gcmaes AVX
   - ESN for inline IPsec tx in chcr
   - Add support for CryptoCell 703 in ccree
   - Add support for CryptoCell 713 in ccree
   - Add SM4 support in ccree
   - Add SM3 support in ccree
   - Add support for chacha20 in caam/qi2
   - Add support for chacha20 + poly1305 in caam/jr
   - Add support for chacha20 + poly1305 in caam/qi2
   - Add AEAD cipher support in cavium/nitrox"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (130 commits)
  crypto: skcipher - remove remnants of internal IV generators
  crypto: cavium/nitrox - Fix build with !CONFIG_DEBUG_FS
  crypto: salsa20-generic - don't unnecessarily use atomic walk
  crypto: skcipher - add might_sleep() to skcipher_walk_virt()
  crypto: x86/chacha - avoid sleeping under kernel_fpu_begin()
  crypto: cavium/nitrox - Added AEAD cipher support
  crypto: mxc-scc - fix build warnings on ARM64
  crypto: api - document missing stats member
  crypto: user - remove unused dump functions
  crypto: chelsio - Fix wrong error counter increments
  crypto: chelsio - Reset counters on cxgb4 Detach
  crypto: chelsio - Handle PCI shutdown event
  crypto: chelsio - cleanup:send addr as value in function argument
  crypto: chelsio - Use same value for both channel in single WR
  crypto: chelsio - Swap location of AAD and IV sent in WR
  crypto: chelsio - remove set but not used variable 'kctx_len'
  crypto: ux500 - Use proper enum in hash_set_dma_transfer
  crypto: ux500 - Use proper enum in cryp_set_dma_transfer
  crypto: aesni - Add scatter/gather avx stubs, and use them in C
  crypto: aesni - Introduce partial block macro
  ..
2018-12-27 13:53:32 -08:00
Linus Torvalds
3f03bf9394 Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull general security subsystem updates from James Morris:
 "The main changes here are Paul Gortmaker's removal of unneccesary
  module.h infrastructure"

* 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  security: integrity: partial revert of make ima_main explicitly non-modular
  security: fs: make inode explicitly non-modular
  security: audit and remove any unnecessary uses of module.h
  security: integrity: make evm_main explicitly non-modular
  keys: remove needless modular infrastructure from ecryptfs_format
  security: integrity: make ima_main explicitly non-modular
  tomoyo: fix small typo
2018-12-27 12:04:52 -08:00
Linus Torvalds
94c13f66e1 security: don't use a negative Opt_err token index
The code uses a bitmap to check for duplicate tokens during parsing, and
that doesn't work at all for the negative Opt_err token case.

There is absolutely no reason to make Opt_err be negative, and in fact
it only confuses things, since some of the affected functions actually
return a positive Opt_xyz enum _or_ a regular negative error code (eg
-EINVAL), and using -1 for Opt_err makes no sense.

There are similar problems in ima_policy.c and key encryption, but they
don't have the immediate bug wrt bitmap handing, and ima_policy.c in
particular needs a different patch to make the enum values match the
token array index.  Mimi is sending that separately.

Reported-by: syzbot+a22e0dc07567662c50bc@syzkaller.appspotmail.com
Reported-by: Eric Biggers <ebiggers@kernel.org>
Fixes: 5208cc8342 ("keys, trusted: fix: *do not* allow duplicate key options")
Fixes: 00d60fd3b9 ("KEYS: Provide keyctls to drive the new key type ops for asymmetric keys [ver #2]")
Cc: James Morris James Morris <jmorris@namei.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-17 16:21:48 -08:00
Dave Jiang
9db67581b9 keys-encrypted: add nvdimm key format type to encrypted keys
Adding nvdimm key format type to encrypted keys in order to limit the size
of the key to 32bytes.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-13 17:54:13 -08:00
Dave Jiang
76ef5e1725 keys: Export lookup_user_key to external users
Export lookup_user_key() symbol in order to allow nvdimm passphrase
update to retrieve user injected keys.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-13 17:54:12 -08:00
Paul Gortmaker
876979c930 security: audit and remove any unnecessary uses of module.h
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.
This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.

The advantage in removing such instances is that module.h itself
sources about 15 other headers; adding significantly to what we feed
cpp, and it can obscure what headers we are effectively using.

Since module.h might have been the implicit source for init.h
(for __init) and for export.h (for EXPORT_SYMBOL) we consider each
instance for the presence of either and replace as needed.

Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: linux-security-module@vger.kernel.org
Cc: linux-integrity@vger.kernel.org
Cc: keyrings@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-12-12 14:58:51 -08:00
Paul Gortmaker
a79860800e keys: remove needless modular infrastructure from ecryptfs_format
Even though the support can be modular, only one file needs to use
all the macros like MODULE_AUTHOR, MODULE_LICENSE etc.  Only the one
responsible for registering/removal with module_init/module_exit
needs to declare these.  In this case, that file is "encrypted.c"
and it already has the MODULE_LICENSE that we are removing here.

Since the file does EXPORT_SYMBOL, we add export.h - and build tests
show that module.h (which includes everything) was hiding an implicit
use of string.h - so that is added as well.

Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-integrity@vger.kernel.org
Cc: keyrings@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-12-12 14:58:50 -08:00
Eric Biggers
3d234b3313 crypto: drop mask=CRYPTO_ALG_ASYNC from 'shash' tfm allocations
'shash' algorithms are always synchronous, so passing CRYPTO_ALG_ASYNC
in the mask to crypto_alloc_shash() has no effect.  Many users therefore
already don't pass it, but some still do.  This inconsistency can cause
confusion, especially since the way the 'mask' argument works is
somewhat counterintuitive.

Thus, just remove the unneeded CRYPTO_ALG_ASYNC flags.

This patch shouldn't change any actual behavior.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20 14:26:55 +08:00
Denis Kenzior
22447981fc KEYS: Move trusted.h to include/keys [ver #2]
Signed-off-by: Denis Kenzior <denkenz@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-26 09:30:47 +01:00
Denis Kenzior
e1ea9f8602 KEYS: trusted: Expose common functionality [ver #2]
This patch exposes some common functionality needed to send TPM commands.
Several functions from keys/trusted.c are exposed for use by the new tpm
key subtype and a module dependency is introduced.

In the future, common functionality between the trusted key type and the
asym_tpm subtype should be factored out into a common utility library.

Signed-off-by: Denis Kenzior <denkenz@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-26 09:30:47 +01:00
David Howells
00d60fd3b9 KEYS: Provide keyctls to drive the new key type ops for asymmetric keys [ver #2]
Provide five keyctl functions that permit userspace to make use of the new
key type ops for accessing and driving asymmetric keys.

 (*) Query an asymmetric key.

	long keyctl(KEYCTL_PKEY_QUERY,
		    key_serial_t key, unsigned long reserved,
		    struct keyctl_pkey_query *info);

     Get information about an asymmetric key.  The information is returned
     in the keyctl_pkey_query struct:

	__u32	supported_ops;

     A bit mask of flags indicating which ops are supported.  This is
     constructed from a bitwise-OR of:

	KEYCTL_SUPPORTS_{ENCRYPT,DECRYPT,SIGN,VERIFY}

	__u32	key_size;

     The size in bits of the key.

	__u16	max_data_size;
	__u16	max_sig_size;
	__u16	max_enc_size;
	__u16	max_dec_size;

     The maximum sizes in bytes of a blob of data to be signed, a signature
     blob, a blob to be encrypted and a blob to be decrypted.

     reserved must be set to 0.  This is intended for future use to hand
     over one or more passphrases needed unlock a key.

     If successful, 0 is returned.  If the key is not an asymmetric key,
     EOPNOTSUPP is returned.

 (*) Encrypt, decrypt, sign or verify a blob using an asymmetric key.

	long keyctl(KEYCTL_PKEY_ENCRYPT,
		    const struct keyctl_pkey_params *params,
		    const char *info,
		    const void *in,
		    void *out);

	long keyctl(KEYCTL_PKEY_DECRYPT,
		    const struct keyctl_pkey_params *params,
		    const char *info,
		    const void *in,
		    void *out);

	long keyctl(KEYCTL_PKEY_SIGN,
		    const struct keyctl_pkey_params *params,
		    const char *info,
		    const void *in,
		    void *out);

	long keyctl(KEYCTL_PKEY_VERIFY,
		    const struct keyctl_pkey_params *params,
		    const char *info,
		    const void *in,
		    const void *in2);

     Use an asymmetric key to perform a public-key cryptographic operation
     a blob of data.

     The parameter block pointed to by params contains a number of integer
     values:

	__s32		key_id;
	__u32		in_len;
	__u32		out_len;
	__u32		in2_len;

     For a given operation, the in and out buffers are used as follows:

	Operation ID		in,in_len	out,out_len	in2,in2_len
	=======================	===============	===============	===========
	KEYCTL_PKEY_ENCRYPT	Raw data	Encrypted data	-
	KEYCTL_PKEY_DECRYPT	Encrypted data	Raw data	-
	KEYCTL_PKEY_SIGN	Raw data	Signature	-
	KEYCTL_PKEY_VERIFY	Raw data	-		Signature

     info is a string of key=value pairs that supply supplementary
     information.

     The __spare space in the parameter block must be set to 0.  This is
     intended, amongst other things, to allow the passing of passphrases
     required to unlock a key.

     If successful, encrypt, decrypt and sign all return the amount of data
     written into the output buffer.  Verification returns 0 on success.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: Denis Kenzior <denkenz@gmail.com>
Tested-by: Denis Kenzior <denkenz@gmail.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-26 09:30:46 +01:00
Lubomir Rintel
8c0f9f5b30 Revert "uapi/linux/keyctl.h: don't use C++ reserved keyword as a struct member name"
This changes UAPI, breaking iwd and libell:

  ell/key.c: In function 'kernel_dh_compute':
  ell/key.c:205:38: error: 'struct keyctl_dh_params' has no member named 'private'; did you mean 'dh_private'?
    struct keyctl_dh_params params = { .private = private,
                                        ^~~~~~~
                                        dh_private

This reverts commit 8a2336e549.

Fixes: 8a2336e549 ("uapi/linux/keyctl.h: don't use C++ reserved keyword as a struct member name")
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Randy Dunlap <rdunlap@infradead.org>
cc: Mat Martineau <mathew.j.martineau@linux.intel.com>
cc: Stephan Mueller <smueller@chronox.de>
cc: James Morris <jmorris@namei.org>
cc: "Serge E. Hallyn" <serge@hallyn.com>
cc: Mat Martineau <mathew.j.martineau@linux.intel.com>
cc: Andrew Morton <akpm@linux-foundation.org>
cc: Linus Torvalds <torvalds@linux-foundation.org>
cc: <stable@vger.kernel.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-25 13:28:58 +02:00
Randy Dunlap
8a2336e549 uapi/linux/keyctl.h: don't use C++ reserved keyword as a struct member name
Since this header is in "include/uapi/linux/", apparently people want to
use it in userspace programs -- even in C++ ones.  However, the header
uses a C++ reserved keyword ("private"), so change that to "dh_private"
instead to allow the header file to be used in C++ userspace.

Fixes https://bugzilla.kernel.org/show_bug.cgi?id=191051
Link: http://lkml.kernel.org/r/0db6c314-1ef4-9bfa-1baa-7214dd2ee061@infradead.org
Fixes: ddbb411487 ("KEYS: Add KEYCTL_DH_COMPUTE command")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Mat Martineau <mathew.j.martineau@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-09-04 16:45:02 -07:00
Herbert Xu
c5f5aeef9b Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux
Merge mainline to pick up c7513c2a27 ("crypto/arm64: aes-ce-gcm -
add missing kernel_neon_begin/end pair").
2018-08-03 17:55:12 +08:00
Eric Biggers
85d7311f19 crypto: remove redundant type flags from tfm allocation
Some crypto API users allocating a tfm with crypto_alloc_$FOO() are also
specifying the type flags for $FOO, e.g. crypto_alloc_shash() with
CRYPTO_ALG_TYPE_SHASH.  But, that's redundant since the crypto API will
override any specified type flag/mask with the correct ones.

So, remove the unneeded flags.

This patch shouldn't change any actual behavior.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-09 00:30:29 +08:00
Eric Biggers
3619dec510 dh key: fix rounding up KDF output length
Commit 383203eff7 ("dh key: get rid of stack allocated array") changed
kdf_ctr() to assume that the length of key material to derive is a
multiple of the digest size.  The length was supposed to be rounded up
accordingly.  However, the round_up() macro was used which only gives
the correct result on power-of-2 arguments, whereas not all hash
algorithms have power-of-2 digest sizes.  In some cases this resulted in
a write past the end of the 'outbuf' buffer.

Fix it by switching to roundup(), which works for non-power-of-2 inputs.

Reported-by: syzbot+486f97f892efeb2075a3@syzkaller.appspotmail.com
Reported-by: syzbot+29d17b7898b41ee120a5@syzkaller.appspotmail.com
Reported-by: syzbot+8a608baf8751184ec727@syzkaller.appspotmail.com
Reported-by: syzbot+d04e58bd384f1fe0b112@syzkaller.appspotmail.com
Fixes: 383203eff7 ("dh key: get rid of stack allocated array")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Tycho Andersen <tycho@tycho.ws>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-06-26 09:43:05 -07:00
Kees Cook
6da2ec5605 treewide: kmalloc() -> kmalloc_array()
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Linus Torvalds
10b1eb7d8c Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security system updates from James Morris:

 - incorporate new socketpair() hook into LSM and wire up the SELinux
   and Smack modules. From David Herrmann:

     "The idea is to allow SO_PEERSEC to be called on AF_UNIX sockets
      created via socketpair(2), and return the same information as if
      you emulated socketpair(2) via a temporary listener socket.

      Right now SO_PEERSEC will return the unlabeled credentials for a
      socketpair, rather than the actual credentials of the creating
      process."

 - remove the unused security_settime LSM hook (Sargun Dhillon).

 - remove some stack allocated arrays from the keys code (Tycho
   Andersen)

* 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  dh key: get rid of stack allocated array for zeroes
  dh key: get rid of stack allocated array
  big key: get rid of stack array allocation
  smack: provide socketpair callback
  selinux: provide socketpair callback
  net: hook socketpair() into LSM
  security: add hook for socketpair()
  security: remove security_settime
2018-06-06 16:15:56 -07:00
Christoph Hellwig
fddda2b7b5 proc: introduce proc_create_seq{,_data}
Variants of proc_create{,_data} that directly take a struct seq_operations
argument and drastically reduces the boilerplate code in the callers.

All trivial callers converted over.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-16 07:23:35 +02:00
Tycho Andersen
890e2abe10 dh key: get rid of stack allocated array for zeroes
We're interested in getting rid of all of the stack allocated arrays in
the kernel: https://lkml.org/lkml/2018/3/7/621

This case is interesting, since we really just need an array of bytes that
are zero. The loop already ensures that if the array isn't exactly the
right size that enough zero bytes will be copied in. So, instead of
choosing this value to be the size of the hash, let's just choose it to be
32, since that is a common size, is not too big, and will not result in too
many extra iterations of the loop.

v2: split out from other patch, just hardcode array size instead of
    dynamically allocating something the right size
v3: fix typo of 256 -> 32

Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Reviewed-by: Kees Cook <keescook@chromium.org>
CC: David Howells <dhowells@redhat.com>
CC: James Morris <jmorris@namei.org>
CC: "Serge E. Hallyn" <serge@hallyn.com>
CC: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-05-11 13:07:49 -07:00
Tycho Andersen
383203eff7 dh key: get rid of stack allocated array
We're interested in getting rid of all of the stack allocated arrays in the
kernel: https://lkml.org/lkml/2018/3/7/621

This particular vla is used as a temporary output buffer in case there is
too much hash output for the destination buffer. Instead, let's just
allocate a buffer that's big enough initially, but only copy back to
userspace the amount that was originally asked for.

v2: allocate enough in the original output buffer vs creating a temporary
    output buffer

Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Reviewed-by: Kees Cook <keescook@chromium.org>
CC: David Howells <dhowells@redhat.com>
CC: James Morris <jmorris@namei.org>
CC: "Serge E. Hallyn" <serge@hallyn.com>
CC: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-05-11 13:07:47 -07:00
Tycho Andersen
a964f39561 big key: get rid of stack array allocation
We're interested in getting rid of all of the stack allocated arrays in the
kernel [1]. This patch simply hardcodes the iv length to match that of the
hardcoded cipher.

[1]: https://lkml.org/lkml/2018/3/7/621

v2: hardcode the length of the nonce to be the GCM AES IV length, and do a
    sanity check in init(), Eric Biggers
v3: * remember to free big_key_aead when sanity check fails
    * define a constant for big key IV size so it can be changed along side
      the algorithm in the code

Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Reviewed-by: Kees Cook <keescook@chromium.org>
CC: David Howells <dhowells@redhat.com>
CC: James Morris <jmorris@namei.org>
CC: "Serge E. Hallyn" <serge@hallyn.com>
CC: Jason A. Donenfeld <Jason@zx2c4.com>
CC: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-05-11 13:07:45 -07:00
Randy Dunlap
514c603249 headers: untangle kmemleak.h from mm.h
Currently <linux/slab.h> #includes <linux/kmemleak.h> for no obvious
reason.  It looks like it's only a convenience, so remove kmemleak.h
from slab.h and add <linux/kmemleak.h> to any users of kmemleak_* that
don't already #include it.  Also remove <linux/kmemleak.h> from source
files that do not use it.

This is tested on i386 allmodconfig and x86_64 allmodconfig.  It would
be good to run it through the 0day bot for other $ARCHes.  I have
neither the horsepower nor the storage space for the other $ARCHes.

Update: This patch has been extensively build-tested by both the 0day
bot & kisskb/ozlabs build farms.  Both of them reported 2 build failures
for which patches are included here (in v2).

[ slab.h is the second most used header file after module.h; kernel.h is
  right there with slab.h. There could be some minor error in the
  counting due to some #includes having comments after them and I didn't
  combine all of those. ]

[akpm@linux-foundation.org: security/keys/big_key.c needs vmalloc.h, per sfr]
Link: http://lkml.kernel.org/r/e4309f98-3749-93e1-4bb7-d9501a39d015@infradead.org
Link: http://kisskb.ellerman.id.au/kisskb/head/13396/
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Reported-by: Michael Ellerman <mpe@ellerman.id.au>	[2 build failures]
Reported-by: Fengguang Wu <fengguang.wu@intel.com>	[2 build failures]
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Cc: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:27 -07:00
David Howells
d9f4bb1a0f KEYS: Use individual pages in big_key for crypto buffers
kmalloc() can't always allocate large enough buffers for big_key to use for
crypto (1MB + some metadata) so we cannot use that to allocate the buffer.
Further, vmalloc'd pages can't be passed to sg_init_one() and the aead
crypto accessors cannot be called progressively and must be passed all the
data in one go (which means we can't pass the data in one block at a time).

Fix this by allocating the buffer pages individually and passing them
through a multientry scatterlist to the crypto layer.  This has the bonus
advantage that we don't have to allocate a contiguous series of pages.

We then vmap() the page list and pass that through to the VFS read/write
routines.

This can trigger a warning:

	WARNING: CPU: 0 PID: 60912 at mm/page_alloc.c:3883 __alloc_pages_nodemask+0xb7c/0x15f8
	([<00000000002acbb6>] __alloc_pages_nodemask+0x1ee/0x15f8)
	 [<00000000002dd356>] kmalloc_order+0x46/0x90
	 [<00000000002dd3e0>] kmalloc_order_trace+0x40/0x1f8
	 [<0000000000326a10>] __kmalloc+0x430/0x4c0
	 [<00000000004343e4>] big_key_preparse+0x7c/0x210
	 [<000000000042c040>] key_create_or_update+0x128/0x420
	 [<000000000042e52c>] SyS_add_key+0x124/0x220
	 [<00000000007bba2c>] system_call+0xc4/0x2b0

from the keyctl/padd/useradd test of the keyutils testsuite on s390x.

Note that it might be better to shovel data through in page-sized lumps
instead as there's no particular need to use a monolithic buffer unless the
kernel itself wants to access the data.

Fixes: 13100a72f4 ("Security: Keys: Big keys stored encrypted")
Reported-by: Paul Bunyan <pbunyan@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Kirill Marinushkin <k.marinushkin@gmail.com>
2018-02-22 14:58:38 +00:00
Linus Torvalds
ae0cb7be35 Merge branch 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull tpm updates from James Morris:

 - reduce polling delays in tpm_tis

 - support retrieving TPM 2.0 Event Log through EFI before
   ExitBootServices

 - replace tpm-rng.c with a hwrng device managed by the driver for each
   TPM device

 - TPM resource manager synthesizes TPM_RC_COMMAND_CODE response instead
   of returning -EINVAL for unknown TPM commands. This makes user space
   more sound.

 - CLKRUN fixes:

    * Keep #CLKRUN disable through the entier TPM command/response flow

    * Check whether #CLKRUN is enabled before disabling and enabling it
      again because enabling it breaks PS/2 devices on a system where it
      is disabled

* 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  tpm: remove unused variables
  tpm: remove unused data fields from I2C and OF device ID tables
  tpm: only attempt to disable the LPC CLKRUN if is already enabled
  tpm: follow coding style for variable declaration in tpm_tis_core_init()
  tpm: delete the TPM_TIS_CLK_ENABLE flag
  tpm: Update MAINTAINERS for Jason Gunthorpe
  tpm: Keep CLKRUN enabled throughout the duration of transmit_cmd()
  tpm_tis: Move ilb_base_addr to tpm_tis_data
  tpm2-cmd: allow more attempts for selftest execution
  tpm: return a TPM_RC_COMMAND_CODE response if command is not implemented
  tpm: Move Linux RNG connection to hwrng
  tpm: use struct tpm_chip for tpm_chip_find_get()
  tpm: parse TPM event logs based on EFI table
  efi: call get_event_log before ExitBootServices
  tpm: add event log format version
  tpm: rename event log provider files
  tpm: move tpm_eventlog.h outside of drivers folder
  tpm: use tpm_msleep() value as max delay
  tpm: reduce tpm polling delay in tpm_tis_core
  tpm: move wait_for_tpm_stat() to respective driver files
2018-01-31 13:12:31 -08:00
Jarkko Sakkinen
aad887f664 tpm: use struct tpm_chip for tpm_chip_find_get()
Device number (the character device index) is not a stable identifier
for a TPM chip. That is the reason why every call site passes
TPM_ANY_NUM to tpm_chip_find_get().

This commit changes the API in a way that instead a struct tpm_chip
instance is given and NULL means the default chip. In addition, this
commit refines the documentation to be up to date with the
implementation.

Suggested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> (@chip_num -> @chip part)
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@ziepe.ca>
Tested-by: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
2018-01-08 12:58:36 +02:00
Ingo Molnar
475c5ee193 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

- Updates to use cond_resched() instead of cond_resched_rcu_qs()
  where feasible (currently everywhere except in kernel/rcu and
  in kernel/torture.c).  Also a couple of fixes to avoid sending
  IPIs to offline CPUs.

- Updates to simplify RCU's dyntick-idle handling.

- Updates to remove almost all uses of smp_read_barrier_depends()
  and read_barrier_depends().

- Miscellaneous fixes.

- Torture-test updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-03 14:14:18 +01:00
Eric Biggers
18026d8668 KEYS: reject NULL restriction string when type is specified
keyctl_restrict_keyring() allows through a NULL restriction when the
"type" is non-NULL, which causes a NULL pointer dereference in
asymmetric_lookup_restriction() when it calls strcmp() on the
restriction string.

But no key types actually use a "NULL restriction" to mean anything, so
update keyctl_restrict_keyring() to reject it with EINVAL.

Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: 97d3aa0f31 ("KEYS: Add a lookup_restriction function for the asymmetric key type")
Cc: <stable@vger.kernel.org> # v4.12+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-12-08 15:13:29 +00:00
Colin Ian King
3d1f025542 security: keys: remove redundant assignment to key_ref
Variable key_ref is being assigned a value that is never read;
key_ref is being re-assigned a few statements later.  Hence this
assignment is redundant and can be removed.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
2017-12-08 15:13:29 +00:00
Eric Biggers
4dca6ea1d9 KEYS: add missing permission check for request_key() destination
When the request_key() syscall is not passed a destination keyring, it
links the requested key (if constructed) into the "default" request-key
keyring.  This should require Write permission to the keyring.  However,
there is actually no permission check.

This can be abused to add keys to any keyring to which only Search
permission is granted.  This is because Search permission allows joining
the keyring.  keyctl_set_reqkey_keyring(KEY_REQKEY_DEFL_SESSION_KEYRING)
then will set the default request-key keyring to the session keyring.
Then, request_key() can be used to add keys to the keyring.

Both negatively and positively instantiated keys can be added using this
method.  Adding negative keys is trivial.  Adding a positive key is a
bit trickier.  It requires that either /sbin/request-key positively
instantiates the key, or that another thread adds the key to the process
keyring at just the right time, such that request_key() misses it
initially but then finds it in construct_alloc_key().

Fix this bug by checking for Write permission to the keyring in
construct_get_dest_keyring() when the default keyring is being used.

We don't do the permission check for non-default keyrings because that
was already done by the earlier call to lookup_user_key().  Also,
request_key_and_link() is currently passed a 'struct key *' rather than
a key_ref_t, so the "possessed" bit is unavailable.

We also don't do the permission check for the "requestor keyring", to
continue to support the use case described by commit 8bbf4976b5
("KEYS: Alter use of key instantiation link-to-keyring argument") where
/sbin/request-key recursively calls request_key() to add keys to the
original requestor's destination keyring.  (I don't know of any users
who actually do that, though...)

Fixes: 3e30148c3d ("[PATCH] Keys: Make request-key create an authorisation key")
Cc: <stable@vger.kernel.org>	# v2.6.13+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-12-08 15:13:27 +00:00
Eric Biggers
a2d8737d5c KEYS: remove unnecessary get/put of explicit dest_keyring
In request_key_and_link(), in the case where the dest_keyring was
explicitly specified, there is no need to get another reference to
dest_keyring before calling key_link(), then drop it afterwards.  This
is because by definition, we already have a reference to dest_keyring.

This change is useful because we'll be making
construct_get_dest_keyring() able to return an error code, and we don't
want to have to handle that error here for no reason.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-12-08 15:13:27 +00:00
Paul E. McKenney
d963007c72 keyring: Remove now-redundant smp_read_barrier_depends()
Now that the associative-array library properly heads dependency chains,
the various smp_read_barrier_depends() calls in security/keys/keyring.c
are no longer needed.  This commit therefore removes them.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: <keyrings@vger.kernel.org>
Cc: <linux-security-module@vger.kernel.org>
Reviewed-by: James Morris <james.l.morris@oracle.com>
2017-12-04 10:53:14 -08:00
Linus Torvalds
844056fd74 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:

 - The final conversion of timer wheel timers to timer_setup().

   A few manual conversions and a large coccinelle assisted sweep and
   the removal of the old initialization mechanisms and the related
   code.

 - Remove the now unused VSYSCALL update code

 - Fix permissions of /proc/timer_list. I still need to get rid of that
   file completely

 - Rename a misnomed clocksource function and remove a stale declaration

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
  m68k/macboing: Fix missed timer callback assignment
  treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts
  timer: Remove redundant __setup_timer*() macros
  timer: Pass function down to initialization routines
  timer: Remove unused data arguments from macros
  timer: Switch callback prototype to take struct timer_list * argument
  timer: Pass timer_list pointer to callbacks unconditionally
  Coccinelle: Remove setup_timer.cocci
  timer: Remove setup_*timer() interface
  timer: Remove init_timer() interface
  treewide: setup_timer() -> timer_setup() (2 field)
  treewide: setup_timer() -> timer_setup()
  treewide: init_timer() -> setup_timer()
  treewide: Switch DEFINE_TIMER callbacks to struct timer_list *
  s390: cmm: Convert timers to use timer_setup()
  lightnvm: Convert timers to use timer_setup()
  drivers/net: cris: Convert timers to use timer_setup()
  drm/vc4: Convert timers to use timer_setup()
  block/laptop_mode: Convert timers to use timer_setup()
  net/atm/mpc: Avoid open-coded assignment of timer callback function
  ...
2017-11-25 08:37:16 -10:00
Kees Cook
24ed960abf treewide: Switch DEFINE_TIMER callbacks to struct timer_list *
This changes all DEFINE_TIMER() callbacks to use a struct timer_list
pointer instead of unsigned long. Since the data argument has already been
removed, none of these callbacks are using their argument currently, so
this renames the argument to "unused".

Done using the following semantic patch:

@match_define_timer@
declarer name DEFINE_TIMER;
identifier _timer, _callback;
@@

 DEFINE_TIMER(_timer, _callback);

@change_callback depends on match_define_timer@
identifier match_define_timer._callback;
type _origtype;
identifier _origarg;
@@

 void
-_callback(_origtype _origarg)
+_callback(struct timer_list *unused)
 { ... }

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 15:57:05 -08:00
Baolin Wang
0a9dd0e071 security: keys: Replace time_t with time64_t for struct key_preparsed_payload
The 'struct key_preparsed_payload' will use 'time_t' which we will
try to remove in the kernel, since 'time_t' is not year 2038 safe on
32bits systems.

Thus this patch replaces 'time_t' with 'time64_t' which is year 2038
safe on 32 bits system for 'struct key_preparsed_payload', moreover
we should use the 'TIME64_MAX' macro to initialize the 'time64_t'
type variable.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
2017-11-15 16:38:45 +00:00
Baolin Wang
074d589895 security: keys: Replace time_t/timespec with time64_t
The 'struct key' will use 'time_t' which we try to remove in the
kernel, since 'time_t' is not year 2038 safe on 32bit systems.
Also the 'struct keyring_search_context' will use 'timespec' type
to record current time, which is also not year 2038 safe on 32bit
systems.

Thus this patch replaces 'time_t' with 'time64_t' which is year 2038
safe for 'struct key', and replace 'timespec' with 'time64_t' for the
'struct keyring_search_context', since we only look at the the seconds
part of 'timespec' variable. Moreover we also change the codes where
using the 'time_t' and 'timespec', and we can get current time by
ktime_get_real_seconds() instead of current_kernel_time(), and use
'TIME64_MAX' macro to initialize the 'time64_t' type variable.

Especially in proc.c file, we have replaced 'unsigned long' and 'timespec'
type with 'u64' and 'time64_t' type to save the timeout value, which means
user will get one 'u64' type timeout value by issuing proc_keys_show()
function.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
2017-11-15 16:38:45 +00:00
Linus Torvalds
2bcc673101 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "Yet another big pile of changes:

   - More year 2038 work from Arnd slowly reaching the point where we
     need to think about the syscalls themself.

   - A new timer function which allows to conditionally (re)arm a timer
     only when it's either not running or the new expiry time is sooner
     than the armed expiry time. This allows to use a single timer for
     multiple timeout requirements w/o caring about the first expiry
     time at the call site.

   - A new NMI safe accessor to clock real time for the printk timestamp
     work. Can be used by tracing, perf as well if required.

   - A large number of timer setup conversions from Kees which got
     collected here because either maintainers requested so or they
     simply got ignored. As Kees pointed out already there are a few
     trivial merge conflicts and some redundant commits which was
     unavoidable due to the size of this conversion effort.

   - Avoid a redundant iteration in the timer wheel softirq processing.

   - Provide a mechanism to treat RTC implementations depending on their
     hardware properties, i.e. don't inflict the write at the 0.5
     seconds boundary which originates from the PC CMOS RTC to all RTCs.
     No functional change as drivers need to be updated separately.

   - The usual small updates to core code clocksource drivers. Nothing
     really exciting"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (111 commits)
  timers: Add a function to start/reduce a timer
  pstore: Use ktime_get_real_fast_ns() instead of __getnstimeofday()
  timer: Prepare to change all DEFINE_TIMER() callbacks
  netfilter: ipvs: Convert timers to use timer_setup()
  scsi: qla2xxx: Convert timers to use timer_setup()
  block/aoe: discover_timer: Convert timers to use timer_setup()
  ide: Convert timers to use timer_setup()
  drbd: Convert timers to use timer_setup()
  mailbox: Convert timers to use timer_setup()
  crypto: Convert timers to use timer_setup()
  drivers/pcmcia: omap1: Fix error in automated timer conversion
  ARM: footbridge: Fix typo in timer conversion
  drivers/sgi-xp: Convert timers to use timer_setup()
  drivers/pcmcia: Convert timers to use timer_setup()
  drivers/memstick: Convert timers to use timer_setup()
  drivers/macintosh: Convert timers to use timer_setup()
  hwrng/xgene-rng: Convert timers to use timer_setup()
  auxdisplay: Convert timers to use timer_setup()
  sparc/led: Convert timers to use timer_setup()
  mips: ip22/32: Convert timers to use timer_setup()
  ...
2017-11-13 17:56:58 -08:00
Linus Torvalds
ead751507d License cleanup: add SPDX license identifiers to some files
Many source files in the tree are missing licensing information, which
 makes it harder for compliance tools to determine the correct license.
 
 By default all files without license information are under the default
 license of the kernel, which is GPL version 2.
 
 Update the files which contain no license information with the 'GPL-2.0'
 SPDX license identifier.  The SPDX identifier is a legally binding
 shorthand, which can be used instead of the full boiler plate text.
 
 This patch is based on work done by Thomas Gleixner and Kate Stewart and
 Philippe Ombredanne.
 
 How this work was done:
 
 Patches were generated and checked against linux-4.14-rc6 for a subset of
 the use cases:
  - file had no licensing information it it.
  - file was a */uapi/* one with no licensing information in it,
  - file was a */uapi/* one with existing licensing information,
 
 Further patches will be generated in subsequent months to fix up cases
 where non-standard license headers were used, and references to license
 had to be inferred by heuristics based on keywords.
 
 The analysis to determine which SPDX License Identifier to be applied to
 a file was done in a spreadsheet of side by side results from of the
 output of two independent scanners (ScanCode & Windriver) producing SPDX
 tag:value files created by Philippe Ombredanne.  Philippe prepared the
 base worksheet, and did an initial spot review of a few 1000 files.
 
 The 4.13 kernel was the starting point of the analysis with 60,537 files
 assessed.  Kate Stewart did a file by file comparison of the scanner
 results in the spreadsheet to determine which SPDX license identifier(s)
 to be applied to the file. She confirmed any determination that was not
 immediately clear with lawyers working with the Linux Foundation.
 
 Criteria used to select files for SPDX license identifier tagging was:
  - Files considered eligible had to be source code files.
  - Make and config files were included as candidates if they contained >5
    lines of source
  - File already had some variant of a license header in it (even if <5
    lines).
 
 All documentation files were explicitly excluded.
 
 The following heuristics were used to determine which SPDX license
 identifiers to apply.
 
  - when both scanners couldn't find any license traces, file was
    considered to have no license information in it, and the top level
    COPYING file license applied.
 
    For non */uapi/* files that summary was:
 
    SPDX license identifier                            # files
    ---------------------------------------------------|-------
    GPL-2.0                                              11139
 
    and resulted in the first patch in this series.
 
    If that file was a */uapi/* path one, it was "GPL-2.0 WITH
    Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
 
    SPDX license identifier                            # files
    ---------------------------------------------------|-------
    GPL-2.0 WITH Linux-syscall-note                        930
 
    and resulted in the second patch in this series.
 
  - if a file had some form of licensing information in it, and was one
    of the */uapi/* ones, it was denoted with the Linux-syscall-note if
    any GPL family license was found in the file or had no licensing in
    it (per prior point).  Results summary:
 
    SPDX license identifier                            # files
    ---------------------------------------------------|------
    GPL-2.0 WITH Linux-syscall-note                       270
    GPL-2.0+ WITH Linux-syscall-note                      169
    ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
    ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
    LGPL-2.1+ WITH Linux-syscall-note                      15
    GPL-1.0+ WITH Linux-syscall-note                       14
    ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
    LGPL-2.0+ WITH Linux-syscall-note                       4
    LGPL-2.1 WITH Linux-syscall-note                        3
    ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
    ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
 
    and that resulted in the third patch in this series.
 
  - when the two scanners agreed on the detected license(s), that became
    the concluded license(s).
 
  - when there was disagreement between the two scanners (one detected a
    license but the other didn't, or they both detected different
    licenses) a manual inspection of the file occurred.
 
  - In most cases a manual inspection of the information in the file
    resulted in a clear resolution of the license that should apply (and
    which scanner probably needed to revisit its heuristics).
 
  - When it was not immediately clear, the license identifier was
    confirmed with lawyers working with the Linux Foundation.
 
  - If there was any question as to the appropriate license identifier,
    the file was flagged for further research and to be revisited later
    in time.
 
 In total, over 70 hours of logged manual review was done on the
 spreadsheet to determine the SPDX license identifiers to apply to the
 source files by Kate, Philippe, Thomas and, in some cases, confirmation
 by lawyers working with the Linux Foundation.
 
 Kate also obtained a third independent scan of the 4.13 code base from
 FOSSology, and compared selected files where the other two scanners
 disagreed against that SPDX file, to see if there was new insights.  The
 Windriver scanner is based on an older version of FOSSology in part, so
 they are related.
 
 Thomas did random spot checks in about 500 files from the spreadsheets
 for the uapi headers and agreed with SPDX license identifier in the
 files he inspected. For the non-uapi files Thomas did random spot checks
 in about 15000 files.
 
 In initial set of patches against 4.14-rc6, 3 files were found to have
 copy/paste license identifier errors, and have been fixed to reflect the
 correct identifier.
 
 Additionally Philippe spent 10 hours this week doing a detailed manual
 inspection and review of the 12,461 patched files from the initial patch
 version early this week with:
  - a full scancode scan run, collecting the matched texts, detected
    license ids and scores
  - reviewing anything where there was a license detected (about 500+
    files) to ensure that the applied SPDX license was correct
  - reviewing anything where there was no detection but the patch license
    was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
    SPDX license was correct
 
 This produced a worksheet with 20 files needing minor correction.  This
 worksheet was then exported into 3 different .csv files for the
 different types of files to be modified.
 
 These .csv files were then reviewed by Greg.  Thomas wrote a script to
 parse the csv files and add the proper SPDX tag to the file, in the
 format that the file expected.  This script was further refined by Greg
 based on the output to detect more types of files automatically and to
 distinguish between header and source .c files (which need different
 comment types.)  Finally Greg ran the script using the .csv files to
 generate the patches.
 
 Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
 Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
 Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCWfswbQ8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ykvEwCfXU1MuYFQGgMdDmAZXEc+xFXZvqgAoKEcHDNA
 6dVh26uchcEQLN/XqUDt
 =x306
 -----END PGP SIGNATURE-----

Merge tag 'spdx_identifiers-4.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull initial SPDX identifiers from Greg KH:
 "License cleanup: add SPDX license identifiers to some files

  Many source files in the tree are missing licensing information, which
  makes it harder for compliance tools to determine the correct license.

  By default all files without license information are under the default
  license of the kernel, which is GPL version 2.

  Update the files which contain no license information with the
  'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally
  binding shorthand, which can be used instead of the full boiler plate
  text.

  This patch is based on work done by Thomas Gleixner and Kate Stewart
  and Philippe Ombredanne.

  How this work was done:

  Patches were generated and checked against linux-4.14-rc6 for a subset
  of the use cases:

   - file had no licensing information it it.

   - file was a */uapi/* one with no licensing information in it,

   - file was a */uapi/* one with existing licensing information,

  Further patches will be generated in subsequent months to fix up cases
  where non-standard license headers were used, and references to
  license had to be inferred by heuristics based on keywords.

  The analysis to determine which SPDX License Identifier to be applied
  to a file was done in a spreadsheet of side by side results from of
  the output of two independent scanners (ScanCode & Windriver)
  producing SPDX tag:value files created by Philippe Ombredanne.
  Philippe prepared the base worksheet, and did an initial spot review
  of a few 1000 files.

  The 4.13 kernel was the starting point of the analysis with 60,537
  files assessed. Kate Stewart did a file by file comparison of the
  scanner results in the spreadsheet to determine which SPDX license
  identifier(s) to be applied to the file. She confirmed any
  determination that was not immediately clear with lawyers working with
  the Linux Foundation.

  Criteria used to select files for SPDX license identifier tagging was:

   - Files considered eligible had to be source code files.

   - Make and config files were included as candidates if they contained
     >5 lines of source

   - File already had some variant of a license header in it (even if <5
     lines).

  All documentation files were explicitly excluded.

  The following heuristics were used to determine which SPDX license
  identifiers to apply.

   - when both scanners couldn't find any license traces, file was
     considered to have no license information in it, and the top level
     COPYING file license applied.

     For non */uapi/* files that summary was:

       SPDX license identifier                            # files
       ---------------------------------------------------|-------
       GPL-2.0                                              11139

     and resulted in the first patch in this series.

     If that file was a */uapi/* path one, it was "GPL-2.0 WITH
     Linux-syscall-note" otherwise it was "GPL-2.0". Results of that
     was:

       SPDX license identifier                            # files
       ---------------------------------------------------|-------
       GPL-2.0 WITH Linux-syscall-note                        930

     and resulted in the second patch in this series.

   - if a file had some form of licensing information in it, and was one
     of the */uapi/* ones, it was denoted with the Linux-syscall-note if
     any GPL family license was found in the file or had no licensing in
     it (per prior point). Results summary:

       SPDX license identifier                            # files
       ---------------------------------------------------|------
       GPL-2.0 WITH Linux-syscall-note                       270
       GPL-2.0+ WITH Linux-syscall-note                      169
       ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
       ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
       LGPL-2.1+ WITH Linux-syscall-note                      15
       GPL-1.0+ WITH Linux-syscall-note                       14
       ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
       LGPL-2.0+ WITH Linux-syscall-note                       4
       LGPL-2.1 WITH Linux-syscall-note                        3
       ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
       ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

     and that resulted in the third patch in this series.

   - when the two scanners agreed on the detected license(s), that
     became the concluded license(s).

   - when there was disagreement between the two scanners (one detected
     a license but the other didn't, or they both detected different
     licenses) a manual inspection of the file occurred.

   - In most cases a manual inspection of the information in the file
     resulted in a clear resolution of the license that should apply
     (and which scanner probably needed to revisit its heuristics).

   - When it was not immediately clear, the license identifier was
     confirmed with lawyers working with the Linux Foundation.

   - If there was any question as to the appropriate license identifier,
     the file was flagged for further research and to be revisited later
     in time.

  In total, over 70 hours of logged manual review was done on the
  spreadsheet to determine the SPDX license identifiers to apply to the
  source files by Kate, Philippe, Thomas and, in some cases,
  confirmation by lawyers working with the Linux Foundation.

  Kate also obtained a third independent scan of the 4.13 code base from
  FOSSology, and compared selected files where the other two scanners
  disagreed against that SPDX file, to see if there was new insights.
  The Windriver scanner is based on an older version of FOSSology in
  part, so they are related.

  Thomas did random spot checks in about 500 files from the spreadsheets
  for the uapi headers and agreed with SPDX license identifier in the
  files he inspected. For the non-uapi files Thomas did random spot
  checks in about 15000 files.

  In initial set of patches against 4.14-rc6, 3 files were found to have
  copy/paste license identifier errors, and have been fixed to reflect
  the correct identifier.

  Additionally Philippe spent 10 hours this week doing a detailed manual
  inspection and review of the 12,461 patched files from the initial
  patch version early this week with:

   - a full scancode scan run, collecting the matched texts, detected
     license ids and scores

   - reviewing anything where there was a license detected (about 500+
     files) to ensure that the applied SPDX license was correct

   - reviewing anything where there was no detection but the patch
     license was not GPL-2.0 WITH Linux-syscall-note to ensure that the
     applied SPDX license was correct

  This produced a worksheet with 20 files needing minor correction. This
  worksheet was then exported into 3 different .csv files for the
  different types of files to be modified.

  These .csv files were then reviewed by Greg. Thomas wrote a script to
  parse the csv files and add the proper SPDX tag to the file, in the
  format that the file expected. This script was further refined by Greg
  based on the output to detect more types of files automatically and to
  distinguish between header and source .c files (which need different
  comment types.) Finally Greg ran the script using the .csv files to
  generate the patches.

  Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
  Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
  Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'spdx_identifiers-4.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  License cleanup: add SPDX license identifier to uapi header files with a license
  License cleanup: add SPDX license identifier to uapi header files with no license
  License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 10:04:46 -07:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Eric Biggers
a3c812f7cf KEYS: trusted: fix writing past end of buffer in trusted_read()
When calling keyctl_read() on a key of type "trusted", if the
user-supplied buffer was too small, the kernel ignored the buffer length
and just wrote past the end of the buffer, potentially corrupting
userspace memory.  Fix it by instead returning the size required, as per
the documentation for keyctl_read().

We also don't even fill the buffer at all in this case, as this is
slightly easier to implement than doing a short read, and either
behavior appears to be permitted.  It also makes it match the behavior
of the "encrypted" key type.

Fixes: d00a1c72f7 ("keys: add new trusted key-type")
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Cc: <stable@vger.kernel.org> # v2.6.38+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-11-02 20:58:07 +11:00
Eric Biggers
3239b6f29b KEYS: return full count in keyring_read() if buffer is too small
Commit e645016abc ("KEYS: fix writing past end of user-supplied buffer
in keyring_read()") made keyring_read() stop corrupting userspace memory
when the user-supplied buffer is too small.  However it also made the
return value in that case be the short buffer size rather than the size
required, yet keyctl_read() is actually documented to return the size
required.  Therefore, switch it over to the documented behavior.

Note that for now we continue to have it fill the short buffer, since it
did that before (pre-v3.13) and dump_key_tree_aux() in keyutils arguably
relies on it.

Fixes: e645016abc ("KEYS: fix writing past end of user-supplied buffer in keyring_read()")
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Cc: <stable@vger.kernel.org> # v3.13+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-11-02 20:58:05 +11:00
Eric Biggers
ab5c69f013 KEYS: load key flags and expiry time atomically in proc_keys_show()
In proc_keys_show(), the key semaphore is not held, so the key ->flags
and ->expiry can be changed concurrently.  We therefore should read them
atomically just once.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-18 09:12:41 +01:00
Eric Biggers
9d6c8711b6 KEYS: Load key expiry time atomically in keyring_search_iterator()
Similar to the case for key_validate(), we should load the key ->expiry
once atomically in keyring_search_iterator(), since it can be changed
concurrently with the flags whenever the key semaphore isn't held.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-18 09:12:41 +01:00
Eric Biggers
1823d475a5 KEYS: load key flags and expiry time atomically in key_validate()
In key_validate(), load the flags and expiry time once atomically, since
these can change concurrently if key_validate() is called without the
key semaphore held.  And we don't want to get inconsistent results if a
variable is referenced multiple times.  For example, key->expiry was
referenced in both 'if (key->expiry)' and in 'if (now.tv_sec >=
key->expiry)', making it theoretically possible to see a spurious
EKEYEXPIRED while the expiration time was being removed, i.e. set to 0.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-18 09:12:41 +01:00
David Howells
60ff5b2f54 KEYS: don't let add_key() update an uninstantiated key
Currently, when passed a key that already exists, add_key() will call the
key's ->update() method if such exists.  But this is heavily broken in the
case where the key is uninstantiated because it doesn't call
__key_instantiate_and_link().  Consequently, it doesn't do most of the
things that are supposed to happen when the key is instantiated, such as
setting the instantiation state, clearing KEY_FLAG_USER_CONSTRUCT and
awakening tasks waiting on it, and incrementing key->user->nikeys.

It also never takes key_construction_mutex, which means that
->instantiate() can run concurrently with ->update() on the same key.  In
the case of the "user" and "logon" key types this causes a memory leak, at
best.  Maybe even worse, the ->update() methods of the "encrypted" and
"trusted" key types actually just dereference a NULL pointer when passed an
uninstantiated key.

Change key_create_or_update() to wait interruptibly for the key to finish
construction before continuing.

This patch only affects *uninstantiated* keys.  For now we still allow a
negatively instantiated key to be updated (thereby positively
instantiating it), although that's broken too (the next patch fixes it)
and I'm not sure that anyone actually uses that functionality either.

Here is a simple reproducer for the bug using the "encrypted" key type
(requires CONFIG_ENCRYPTED_KEYS=y), though as noted above the bug
pertained to more than just the "encrypted" key type:

    #include <stdlib.h>
    #include <unistd.h>
    #include <keyutils.h>

    int main(void)
    {
        int ringid = keyctl_join_session_keyring(NULL);

        if (fork()) {
            for (;;) {
                const char payload[] = "update user:foo 32";

                usleep(rand() % 10000);
                add_key("encrypted", "desc", payload, sizeof(payload), ringid);
                keyctl_clear(ringid);
            }
        } else {
            for (;;)
                request_key("encrypted", "desc", "callout_info", ringid);
        }
    }

It causes:

    BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
    IP: encrypted_update+0xb0/0x170
    PGD 7a178067 P4D 7a178067 PUD 77269067 PMD 0
    PREEMPT SMP
    CPU: 0 PID: 340 Comm: reproduce Tainted: G      D         4.14.0-rc1-00025-g428490e38b2e #796
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
    task: ffff8a467a39a340 task.stack: ffffb15c40770000
    RIP: 0010:encrypted_update+0xb0/0x170
    RSP: 0018:ffffb15c40773de8 EFLAGS: 00010246
    RAX: 0000000000000000 RBX: ffff8a467a275b00 RCX: 0000000000000000
    RDX: 0000000000000005 RSI: ffff8a467a275b14 RDI: ffffffffb742f303
    RBP: ffffb15c40773e20 R08: 0000000000000000 R09: ffff8a467a275b17
    R10: 0000000000000020 R11: 0000000000000000 R12: 0000000000000000
    R13: 0000000000000000 R14: ffff8a4677057180 R15: ffff8a467a275b0f
    FS:  00007f5d7fb08700(0000) GS:ffff8a467f200000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000000000018 CR3: 0000000077262005 CR4: 00000000001606f0
    Call Trace:
     key_create_or_update+0x2bc/0x460
     SyS_add_key+0x10c/0x1d0
     entry_SYSCALL_64_fastpath+0x1f/0xbe
    RIP: 0033:0x7f5d7f211259
    RSP: 002b:00007ffed03904c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8
    RAX: ffffffffffffffda RBX: 000000003b2a7955 RCX: 00007f5d7f211259
    RDX: 00000000004009e4 RSI: 00000000004009ff RDI: 0000000000400a04
    RBP: 0000000068db8bad R08: 000000003b2a7955 R09: 0000000000000004
    R10: 000000000000001a R11: 0000000000000246 R12: 0000000000400868
    R13: 00007ffed03905d0 R14: 0000000000000000 R15: 0000000000000000
    Code: 77 28 e8 64 34 1f 00 45 31 c0 31 c9 48 8d 55 c8 48 89 df 48 8d 75 d0 e8 ff f9 ff ff 85 c0 41 89 c4 0f 88 84 00 00 00 4c 8b 7d c8 <49> 8b 75 18 4c 89 ff e8 24 f8 ff ff 85 c0 41 89 c4 78 6d 49 8b
    RIP: encrypted_update+0xb0/0x170 RSP: ffffb15c40773de8
    CR2: 0000000000000018

Cc: <stable@vger.kernel.org> # v2.6.12+
Reported-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Eric Biggers <ebiggers@google.com>
2017-10-18 09:12:40 +01:00
David Howells
363b02dab0 KEYS: Fix race between updating and finding a negative key
Consolidate KEY_FLAG_INSTANTIATED, KEY_FLAG_NEGATIVE and the rejection
error into one field such that:

 (1) The instantiation state can be modified/read atomically.

 (2) The error can be accessed atomically with the state.

 (3) The error isn't stored unioned with the payload pointers.

This deals with the problem that the state is spread over three different
objects (two bits and a separate variable) and reading or updating them
atomically isn't practical, given that not only can uninstantiated keys
change into instantiated or rejected keys, but rejected keys can also turn
into instantiated keys - and someone accessing the key might not be using
any locking.

The main side effect of this problem is that what was held in the payload
may change, depending on the state.  For instance, you might observe the
key to be in the rejected state.  You then read the cached error, but if
the key semaphore wasn't locked, the key might've become instantiated
between the two reads - and you might now have something in hand that isn't
actually an error code.

The state is now KEY_IS_UNINSTANTIATED, KEY_IS_POSITIVE or a negative error
code if the key is negatively instantiated.  The key_is_instantiated()
function is replaced with key_is_positive() to avoid confusion as negative
keys are also 'instantiated'.

Additionally, barriering is included:

 (1) Order payload-set before state-set during instantiation.

 (2) Order state-read before payload-read when using the key.

Further separate barriering is necessary if RCU is being used to access the
payload content after reading the payload pointers.

Fixes: 146aa8b145 ("KEYS: Merge the type-specific data with the payload data")
Cc: stable@vger.kernel.org # v4.4+
Reported-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
2017-10-18 09:12:40 +01:00
Arnd Bergmann
3cd18d1981 security/keys: BIG_KEY requires CONFIG_CRYPTO
The recent rework introduced a possible randconfig build failure
when CONFIG_CRYPTO configured to only allow modules:

security/keys/big_key.o: In function `big_key_crypt':
big_key.c:(.text+0x29f): undefined reference to `crypto_aead_setkey'
security/keys/big_key.o: In function `big_key_init':
big_key.c:(.init.text+0x1a): undefined reference to `crypto_alloc_aead'
big_key.c:(.init.text+0x45): undefined reference to `crypto_aead_setauthsize'
big_key.c:(.init.text+0x77): undefined reference to `crypto_destroy_tfm'
crypto/gcm.o: In function `gcm_hash_crypt_remain_continue':
gcm.c:(.text+0x167): undefined reference to `crypto_ahash_finup'
crypto/gcm.o: In function `crypto_gcm_exit_tfm':
gcm.c:(.text+0x847): undefined reference to `crypto_destroy_tfm'

When we 'select CRYPTO' like the other users, we always get a
configuration that builds.

Fixes: 428490e38b ("security/keys: rewrite all of big_key crypto")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-18 09:12:40 +01:00
Eric Biggers
13923d0865 KEYS: encrypted: fix dereference of NULL user_key_payload
A key of type "encrypted" references a "master key" which is used to
encrypt and decrypt the encrypted key's payload.  However, when we
accessed the master key's payload, we failed to handle the case where
the master key has been revoked, which sets the payload pointer to NULL.
Note that request_key() *does* skip revoked keys, but there is still a
window where the key can be revoked before we acquire its semaphore.

Fix it by checking for a NULL payload, treating it like a key which was
already revoked at the time it was requested.

This was an issue for master keys of type "user" only.  Master keys can
also be of type "trusted", but those cannot be revoked.

Fixes: 7e70cb4978 ("keys: add new key-type encrypted")
Reviewed-by: James Morris <james.l.morris@oracle.com>
Cc: <stable@vger.kernel.org>    [v2.6.38+]
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: David Safford <safford@us.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-12 15:55:09 +01:00
Kees Cook
1d27e3e225 timer: Remove expires and data arguments from DEFINE_TIMER
Drop the arguments from the macro and adjust all callers with the
following script:

  perl -pi -e 's/DEFINE_TIMER\((.*), 0, 0\);/DEFINE_TIMER($1);/g;' \
    $(git grep DEFINE_TIMER | cut -d: -f1 | sort -u | grep -v timer.h)

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # for m68k parts
Acked-by: Guenter Roeck <linux@roeck-us.net> # for watchdog parts
Acked-by: David S. Miller <davem@davemloft.net> # for networking parts
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Kalle Valo <kvalo@codeaurora.org> # for wireless parts
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: linux-mips@linux-mips.org
Cc: Petr Mladek <pmladek@suse.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Kalle Valo <kvalo@qca.qualcomm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: linux1394-devel@lists.sourceforge.net
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: linux-s390@vger.kernel.org
Cc: linux-wireless@vger.kernel.org
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ursula Braun <ubraun@linux.vnet.ibm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Harish Patil <harish.patil@cavium.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Michael Reed <mdr@sgi.com>
Cc: Manish Chopra <manish.chopra@cavium.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-pm@vger.kernel.org
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Mark Gross <mark.gross@intel.com>
Cc: linux-watchdog@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: netdev@vger.kernel.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Link: https://lkml.kernel.org/r/1507159627-127660-11-git-send-email-keescook@chromium.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-10-05 15:01:20 +02:00
Jason A. Donenfeld
428490e38b security/keys: rewrite all of big_key crypto
This started out as just replacing the use of crypto/rng with
get_random_bytes_wait, so that we wouldn't use bad randomness at boot
time. But, upon looking further, it appears that there were even deeper
underlying cryptographic problems, and that this seems to have been
committed with very little crypto review. So, I rewrote the whole thing,
trying to keep to the conventions introduced by the previous author, to
fix these cryptographic flaws.

It makes no sense to seed crypto/rng at boot time and then keep
using it like this, when in fact there's already get_random_bytes_wait,
which can ensure there's enough entropy and be a much more standard way
of generating keys. Since this sensitive material is being stored
untrusted, using ECB and no authentication is simply not okay at all. I
find it surprising and a bit horrifying that this code even made it past
basic crypto review, which perhaps points to some larger issues. This
patch moves from using AES-ECB to using AES-GCM. Since keys are uniquely
generated each time, we can set the nonce to zero. There was also a race
condition in which the same key would be reused at the same time in
different threads. A mutex fixes this issue now.

So, to summarize, this commit fixes the following vulnerabilities:

  * Low entropy key generation, allowing an attacker to potentially
    guess or predict keys.
  * Unauthenticated encryption, allowing an attacker to modify the
    cipher text in particular ways in order to manipulate the plaintext,
    which is is even more frightening considering the next point.
  * Use of ECB mode, allowing an attacker to trivially swap blocks or
    compare identical plaintext blocks.
  * Key re-use.
  * Faulty memory zeroing.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kirill Marinushkin <k.marinushkin@gmail.com>
Cc: security@kernel.org
Cc: stable@vger.kernel.org
2017-09-25 23:31:58 +01:00
Jason A. Donenfeld
910801809b security/keys: properly zero out sensitive key material in big_key
Error paths forgot to zero out sensitive material, so this patch changes
some kfrees into a kzfrees.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Eric Biggers <ebiggers3@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kirill Marinushkin <k.marinushkin@gmail.com>
Cc: security@kernel.org
Cc: stable@vger.kernel.org
2017-09-25 23:31:41 +01:00
Eric Biggers
e007ce9c59 KEYS: use kmemdup() in request_key_auth_new()
kmemdup() is preferred to kmalloc() followed by memcpy().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25 15:19:57 +01:00
Eric Biggers
4aa68e07d8 KEYS: restrict /proc/keys by credentials at open time
When checking for permission to view keys whilst reading from
/proc/keys, we should use the credentials with which the /proc/keys file
was opened.  This is because, in a classic type of exploit, it can be
possible to bypass checks for the *current* credentials by passing the
file descriptor to a suid program.

Following commit 34dbbcdbf6 ("Make file credentials available to the
seqfile interfaces") we can finally fix it.  So let's do it.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25 15:19:57 +01:00
Eric Biggers
8f674565d4 KEYS: reset parent each time before searching key_user_tree
In key_user_lookup(), if there is no key_user for the given uid, we drop
key_user_lock, allocate a new key_user, and search the tree again.  But
we failed to set 'parent' to NULL at the beginning of the second search.
If the tree were to be empty for the second search, the insertion would
be done with an invalid 'parent', scribbling over freed memory.

Fortunately this can't actually happen currently because the tree always
contains at least the root_key_user.  But it still should be fixed to
make the code more robust.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25 15:19:57 +01:00
Eric Biggers
37863c43b2 KEYS: prevent KEYCTL_READ on negative key
Because keyctl_read_key() looks up the key with no permissions
requested, it may find a negatively instantiated key.  If the key is
also possessed, we went ahead and called ->read() on the key.  But the
key payload will actually contain the ->reject_error rather than the
normal payload.  Thus, the kernel oopses trying to read the
user_key_payload from memory address (int)-ENOKEY = 0x00000000ffffff82.

Fortunately the payload data is stored inline, so it shouldn't be
possible to abuse this as an arbitrary memory read primitive...

Reproducer:
    keyctl new_session
    keyctl request2 user desc '' @s
    keyctl read $(keyctl show | awk '/user: desc/ {print $1}')

It causes a crash like the following:
     BUG: unable to handle kernel paging request at 00000000ffffff92
     IP: user_read+0x33/0xa0
     PGD 36a54067 P4D 36a54067 PUD 0
     Oops: 0000 [#1] SMP
     CPU: 0 PID: 211 Comm: keyctl Not tainted 4.14.0-rc1 #337
     Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-20170228_101828-anatol 04/01/2014
     task: ffff90aa3b74c3c0 task.stack: ffff9878c0478000
     RIP: 0010:user_read+0x33/0xa0
     RSP: 0018:ffff9878c047bee8 EFLAGS: 00010246
     RAX: 0000000000000001 RBX: ffff90aa3d7da340 RCX: 0000000000000017
     RDX: 0000000000000000 RSI: 00000000ffffff82 RDI: ffff90aa3d7da340
     RBP: ffff9878c047bf00 R08: 00000024f95da94f R09: 0000000000000000
     R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
     R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
     FS:  00007f58ece69740(0000) GS:ffff90aa3e200000(0000) knlGS:0000000000000000
     CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
     CR2: 00000000ffffff92 CR3: 0000000036adc001 CR4: 00000000003606f0
     Call Trace:
      keyctl_read_key+0xac/0xe0
      SyS_keyctl+0x99/0x120
      entry_SYSCALL_64_fastpath+0x1f/0xbe
     RIP: 0033:0x7f58ec787bb9
     RSP: 002b:00007ffc8d401678 EFLAGS: 00000206 ORIG_RAX: 00000000000000fa
     RAX: ffffffffffffffda RBX: 00007ffc8d402800 RCX: 00007f58ec787bb9
     RDX: 0000000000000000 RSI: 00000000174a63ac RDI: 000000000000000b
     RBP: 0000000000000004 R08: 00007ffc8d402809 R09: 0000000000000020
     R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffc8d402800
     R13: 00007ffc8d4016e0 R14: 0000000000000000 R15: 0000000000000000
     Code: e5 41 55 49 89 f5 41 54 49 89 d4 53 48 89 fb e8 a4 b4 ad ff 85 c0 74 09 80 3d b9 4c 96 00 00 74 43 48 8b b3 20 01 00 00 4d 85 ed <0f> b7 5e 10 74 29 4d 85 e4 74 24 4c 39 e3 4c 89 e2 4c 89 ef 48
     RIP: user_read+0x33/0xa0 RSP: ffff9878c047bee8
     CR2: 00000000ffffff92

Fixes: 61ea0c0ba9 ("KEYS: Skip key state checks when checking for possession")
Cc: <stable@vger.kernel.org>	[v3.13+]
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25 15:19:57 +01:00
Eric Biggers
237bbd29f7 KEYS: prevent creating a different user's keyrings
It was possible for an unprivileged user to create the user and user
session keyrings for another user.  For example:

    sudo -u '#3000' sh -c 'keyctl add keyring _uid.4000 "" @u
                           keyctl add keyring _uid_ses.4000 "" @u
                           sleep 15' &
    sleep 1
    sudo -u '#4000' keyctl describe @u
    sudo -u '#4000' keyctl describe @us

This is problematic because these "fake" keyrings won't have the right
permissions.  In particular, the user who created them first will own
them and will have full access to them via the possessor permissions,
which can be used to compromise the security of a user's keys:

    -4: alswrv-----v------------  3000     0 keyring: _uid.4000
    -5: alswrv-----v------------  3000     0 keyring: _uid_ses.4000

Fix it by marking user and user session keyrings with a flag
KEY_FLAG_UID_KEYRING.  Then, when searching for a user or user session
keyring by name, skip all keyrings that don't have the flag set.

Fixes: 69664cf16a ("keys: don't generate user and user session keyrings unless they're accessed")
Cc: <stable@vger.kernel.org>	[v2.6.26+]
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25 15:19:57 +01:00
Eric Biggers
e645016abc KEYS: fix writing past end of user-supplied buffer in keyring_read()
Userspace can call keyctl_read() on a keyring to get the list of IDs of
keys in the keyring.  But if the user-supplied buffer is too small, the
kernel would write the full list anyway --- which will corrupt whatever
userspace memory happened to be past the end of the buffer.  Fix it by
only filling the space that is available.

Fixes: b2a4df200d ("KEYS: Expand the capacity of a keyring")
Cc: <stable@vger.kernel.org>	[v3.13+]
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25 15:19:57 +01:00
Eric Biggers
7fc0786d95 KEYS: fix key refcount leak in keyctl_read_key()
In keyctl_read_key(), if key_permission() were to return an error code
other than EACCES, we would leak a the reference to the key.  This can't
actually happen currently because key_permission() can only return an
error code other than EACCES if security_key_permission() does, only
SELinux and Smack implement that hook, and neither can return an error
code other than EACCES.  But it should still be fixed, as it is a bug
waiting to happen.

Fixes: 29db919063 ("[PATCH] Keys: Add LSM hooks for key management [try #3]")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25 15:19:57 +01:00
Eric Biggers
884bee0215 KEYS: fix key refcount leak in keyctl_assume_authority()
In keyctl_assume_authority(), if keyctl_change_reqkey_auth() were to
fail, we would leak the reference to the 'authkey'.  Currently this can
only happen if prepare_creds() fails to allocate memory.  But it still
should be fixed, as it is a more severe bug waiting to happen.

This patch also moves the read of 'authkey->serial' to before the
reference to the authkey is dropped.  Doing the read after dropping the
reference is very fragile because it assumes we still hold another
reference to the key.  (Which we do, in current->cred->request_key_auth,
but there's no reason not to write it in the "obviously correct" way.)

Fixes: d84f4f992c ("CRED: Inaugurate COW credentials")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25 15:19:57 +01:00
Eric Biggers
f7b48cf08f KEYS: don't revoke uninstantiated key in request_key_auth_new()
If key_instantiate_and_link() were to fail (which fortunately isn't
possible currently), the call to key_revoke(authkey) would crash with a
NULL pointer dereference in request_key_auth_revoke() because the key
has not yet been instantiated.

Fix this by removing the call to key_revoke().  key_put() is sufficient,
as it's not possible for an uninstantiated authkey to have been used for
anything yet.

Fixes: b5f545c880 ("[PATCH] keys: Permit running process to instantiate keys")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25 15:19:56 +01:00
Eric Biggers
44d8143340 KEYS: fix cred refcount leak in request_key_auth_new()
In request_key_auth_new(), if key_alloc() or key_instantiate_and_link()
were to fail, we would leak a reference to the 'struct cred'.  Currently
this can only happen if key_alloc() fails to allocate memory.  But it
still should be fixed, as it is a more severe bug waiting to happen.

Fix it by cleaning things up to use a helper function which frees a
'struct request_key_auth' correctly.

Fixes: d84f4f992c ("CRED: Inaugurate COW credentials")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25 15:03:55 +01:00
Christoph Hellwig
e13ec939e9 fs: fix kernel_write prototype
Make the position an in/out argument like all the other read/write
helpers and and make the buf argument a void pointer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-04 19:05:15 -04:00
Christoph Hellwig
bdd1d2d3d2 fs: fix kernel_read prototype
Use proper ssize_t and size_t types for the return value and count
argument, move the offset last and make it an in/out argument like
all other read/write helpers, and make the buf argument a void pointer
to get rid of lots of casts in the callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-04 19:05:15 -04:00
Linus Torvalds
e06fdaf40a Now that IPC and other changes have landed, enable manual markings for
randstruct plugin, including the task_struct.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 Comment: Kees Cook <kees@outflux.net>
 
 iQIcBAABCgAGBQJZbRgGAAoJEIly9N/cbcAmk2AQAIL60aQ+9RIcFAXriFhnd7Z2
 x9Jqi9JNc8NgPFXx8GhE4J4eTZ5PwcjgXBpNRWY/laBkRyoBHn24ku09YxrJjmHz
 ZSUsP+/iO9lVeEfbmU9Tnk50afkfwx6bHXBwkiVGQWHtybNVUqA19JbqkHeg8ubx
 myKLGeUv5PPCodRIcBDD0+HaAANcsqtgbDpgmWU8s+IXWwvWCE2p7PuBw7v3HHgH
 qzlPDHYQCRDw+LWsSqPaHj+9mbRO18P/ydMoZHGH4Hl3YYNtty8ZbxnraI3A7zBL
 6mLUVcZ+/l88DqHc5I05T8MmLU1yl2VRxi8/jpMAkg9wkvZ5iNAtlEKIWU6eqsvk
 vaImNOkViLKlWKF+oUD1YdG16d8Segrc6m4MGdI021tb+LoGuUbkY7Tl4ee+3dl/
 9FM+jPv95HjJnyfRNGidh2TKTa9KJkh6DYM9aUnktMFy3ca1h/LuszOiN0LTDiHt
 k5xoFURk98XslJJyXM8FPwXCXiRivrXMZbg5ixNoS4aYSBLv7Cn1M6cPnSOs7UPh
 FqdNPXLRZ+vabSxvEg5+41Ioe0SHqACQIfaSsV5BfF2rrRRdaAxK4h7DBcI6owV2
 7ziBN1nBBq2onYGbARN6ApyCqLcchsKtQfiZ0iFsvW7ZawnkVOOObDTCgPl3tdkr
 403YXzphQVzJtpT5eRV6
 =ngAW
 -----END PGP SIGNATURE-----

Merge tag 'gcc-plugins-v4.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull structure randomization updates from Kees Cook:
 "Now that IPC and other changes have landed, enable manual markings for
  randstruct plugin, including the task_struct.

  This is the rest of what was staged in -next for the gcc-plugins, and
  comes in three patches, largest first:

   - mark "easy" structs with __randomize_layout

   - mark task_struct with an optional anonymous struct to isolate the
     __randomize_layout section

   - mark structs to opt _out_ of automated marking (which will come
     later)

  And, FWIW, this continues to pass allmodconfig (normal and patched to
  enable gcc-plugins) builds of x86_64, i386, arm64, arm, powerpc, and
  s390 for me"

* tag 'gcc-plugins-v4.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  randstruct: opt-out externally exposed function pointer structs
  task_struct: Allow randomized layout
  randstruct: Mark various structs for randomization
2017-07-19 08:55:18 -07:00
Eric Biggers
4f9dabfaf8 KEYS: DH: validate __spare field
Syscalls must validate that their reserved arguments are zero and return
EINVAL otherwise.  Otherwise, it will be impossible to actually use them
for anything in the future because existing programs may be passing
garbage in.  This is standard practice when adding new APIs.

Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-07-14 11:01:38 +10:00
Linus Torvalds
650fc870a2 There has been a fair amount of activity in the docs tree this time
around.  Highlights include:
 
  - Conversion of a bunch of security documentation into RST
 
  - The conversion of the remaining DocBook templates by The Amazing
    Mauro Machine.  We can now drop the entire DocBook build chain.
 
  - The usual collection of fixes and minor updates.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJZWkGAAAoJEI3ONVYwIuV6rf0P/0B3JTiVPKS/WUx53+jzbAi4
 1BN7dmmuMxE1bWpgdEq+ac4aKxm07iAojuntuMj0qz/ZB1WARcmvEqqzI5i4wfq9
 5MrLduLkyuWfr4MOPseKJ2VK83p8nkMOiO7jmnBsilu7fE4nF+5YY9j4cVaArfMy
 cCQvAGjQzvej2eiWMGUSLHn4QFKh00aD7cwKyBVsJ08b27C9xL0J2LQyCDZ4yDgf
 37/MH3puEd3HX/4qAwLonIxT3xrIrrbDturqLU7OSKcWTtGZNrYyTFbwR3RQtqWd
 H8YZVg2Uyhzg9MYhkbQ2E5dEjUP4mkegcp6/JTINH++OOPpTbdTJgirTx7VTkSf1
 +kL8t7+Ayxd0FH3+77GJ5RMj8LUK6rj5cZfU5nClFQKWXP9UL3IelQ3Nl+SpdM8v
 ZAbR2KjKgH9KS6+cbIhgFYlvY+JgPkOVruwbIAc7wXVM3ibk1sWoBOFEujcbueWh
 yDpQv3l1UX0CKr3jnevJoW26LtEbGFtC7gSKZ+3btyeSBpWFGlii42KNycEGwUW0
 ezlwryDVHzyTUiKllNmkdK4v73mvPsZHEjgmme4afKAIiUilmcUF4XcqD86hISFT
 t+UJLA/zEU+0sJe26o2nK6GNJzmo4oCtVyxfhRe26Ojs1n80xlYgnZRfuIYdd31Z
 nwLBnwDCHAOyX91WXp9G
 =cVjZ
 -----END PGP SIGNATURE-----

Merge tag 'docs-4.13' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "There has been a fair amount of activity in the docs tree this time
  around. Highlights include:

   - Conversion of a bunch of security documentation into RST

   - The conversion of the remaining DocBook templates by The Amazing
     Mauro Machine. We can now drop the entire DocBook build chain.

   - The usual collection of fixes and minor updates"

* tag 'docs-4.13' of git://git.lwn.net/linux: (90 commits)
  scripts/kernel-doc: handle DECLARE_HASHTABLE
  Documentation: atomic_ops.txt is core-api/atomic_ops.rst
  Docs: clean up some DocBook loose ends
  Make the main documentation title less Geocities
  Docs: Use kernel-figure in vidioc-g-selection.rst
  Docs: fix table problems in ras.rst
  Docs: Fix breakage with Sphinx 1.5 and upper
  Docs: Include the Latex "ifthen" package
  doc/kokr/howto: Only send regression fixes after -rc1
  docs-rst: fix broken links to dynamic-debug-howto in kernel-parameters
  doc: Document suitability of IBM Verse for kernel development
  Doc: fix a markup error in coding-style.rst
  docs: driver-api: i2c: remove some outdated information
  Documentation: DMA API: fix a typo in a function name
  Docs: Insert missing space to separate link from text
  doc/ko_KR/memory-barriers: Update control-dependencies example
  Documentation, kbuild: fix typo "minimun" -> "minimum"
  docs: Fix some formatting issues in request-key.rst
  doc: ReSTify keys-trusted-encrypted.txt
  doc: ReSTify keys-request-key.txt
  ...
2017-07-03 21:13:25 -07:00
Kees Cook
3859a271a0 randstruct: Mark various structs for randomization
This marks many critical kernel structures for randomization. These are
structures that have been targeted in the past in security exploits, or
contain functions pointers, pointers to function pointer tables, lists,
workqueues, ref-counters, credentials, permissions, or are otherwise
sensitive. This initial list was extracted from Brad Spengler/PaX Team's
code in the last public patch of grsecurity/PaX based on my understanding
of the code. Changes or omissions from the original code are mine and
don't reflect the original grsecurity/PaX code.

Left out of this list is task_struct, which requires special handling
and will be covered in a subsequent patch.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-06-30 12:00:51 -07:00
Ingo Molnar
5dd43ce2f6 sched/wait: Split out the wait_bit*() APIs from <linux/wait.h> into <linux/wait_bit.h>
The wait_bit*() types and APIs are mixed into wait.h, but they
are a pretty orthogonal extension of wait-queues.

Furthermore, only about 50 kernel files use these APIs, while
over 1000 use the regular wait-queue functionality.

So clean up the main wait.h by moving the wait-bit functionality
out of it, into a separate .h and .c file:

  include/linux/wait_bit.h  for types and APIs
  kernel/sched/wait_bit.c   for the implementation

Update all header dependencies.

This reduces the size of wait.h rather significantly, by about 30%.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20 12:19:09 +02:00
Mark Rutland
92347cfd62 KEYS: fix refcount_inc() on zero
If a key's refcount is dropped to zero between key_lookup() peeking at
the refcount and subsequently attempting to increment it, refcount_inc()
will see a zero refcount.  Here, refcount_inc() will WARN_ONCE(), and
will *not* increment the refcount, which will remain zero.

Once key_lookup() drops key_serial_lock, it is possible for the key to
be freed behind our back.

This patch uses refcount_inc_not_zero() to perform the peek and increment
atomically.

Fixes: fff292914d ("security, keys: convert key.usage from atomic_t to refcount_t")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:50 +10:00
Mat Martineau
7cbe0932c2 KEYS: Convert KEYCTL_DH_COMPUTE to use the crypto KPP API
The initial Diffie-Hellman computation made direct use of the MPI
library because the crypto module did not support DH at the time. Now
that KPP is implemented, KEYCTL_DH_COMPUTE should use it to get rid of
duplicate code and leverage possible hardware acceleration.

This fixes an issue whereby the input to the KDF computation would
include additional uninitialized memory when the result of the
Diffie-Hellman computation was shorter than the input prime number.

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:50 +10:00
Eric Biggers
0ddd9f1a6b KEYS: DH: ensure the KDF counter is properly aligned
Accessing a 'u8[4]' through a '__be32 *' violates alignment rules.  Just
make the counter a __be32 instead.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:49 +10:00
Eric Biggers
281590b422 KEYS: DH: don't feed uninitialized "otherinfo" into KDF
If userspace called KEYCTL_DH_COMPUTE with kdf_params containing NULL
otherinfo but nonzero otherinfolen, the kernel would allocate a buffer
for the otherinfo, then feed it into the KDF without initializing it.
Fix this by always doing the copy from userspace (which will fail with
EFAULT in this scenario).

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:49 +10:00
Eric Biggers
bbe240454d KEYS: DH: forbid using digest_null as the KDF hash
Requesting "digest_null" in the keyctl_kdf_params caused an infinite
loop in kdf_ctr() because the "null" hash has a digest size of 0.  Fix
it by rejecting hash algorithms with a digest size of 0.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:49 +10:00
Eric Biggers
0620fddb56 KEYS: sanitize key structs before freeing
While a 'struct key' itself normally does not contain sensitive
information, Documentation/security/keys.txt actually encourages this:

     "Having a payload is not required; and the payload can, in fact,
     just be a value stored in the struct key itself."

In case someone has taken this advice, or will take this advice in the
future, zero the key structure before freeing it.  We might as well, and
as a bonus this could make it a bit more difficult for an adversary to
determine which keys have recently been in use.

This is safe because the key_jar cache does not use a constructor.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:48 +10:00
Eric Biggers
ee618b4619 KEYS: trusted: sanitize all key material
As the previous patch did for encrypted-keys, zero sensitive any
potentially sensitive data related to the "trusted" key type before it
is freed.  Notably, we were not zeroing the tpm_buf structures in which
the actual key is stored for TPM seal and unseal, nor were we zeroing
the trusted_key_payload in certain error paths.

Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: David Safford <safford@us.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:48 +10:00
Eric Biggers
a9dd74b252 KEYS: encrypted: sanitize all key material
For keys of type "encrypted", consistently zero sensitive key material
before freeing it.  This was already being done for the decrypted
payloads of encrypted keys, but not for the master key and the keys
derived from the master key.

Out of an abundance of caution and because it is trivial to do so, also
zero buffers containing the key payload in encrypted form, although
depending on how the encrypted-keys feature is used such information
does not necessarily need to be kept secret.

Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: David Safford <safford@us.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:48 +10:00
Eric Biggers
6966c74932 KEYS: user_defined: sanitize key payloads
Zero the payloads of user and logon keys before freeing them.  This
prevents sensitive key material from being kept around in the slab
caches after a key is released.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:48 +10:00
Eric Biggers
57070c850a KEYS: sanitize add_key() and keyctl() key payloads
Before returning from add_key() or one of the keyctl() commands that
takes in a key payload, zero the temporary buffer that was allocated to
hold the key payload copied from userspace.  This may contain sensitive
key material that should not be kept around in the slab caches.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:48 +10:00
Eric Biggers
63a0b0509e KEYS: fix freeing uninitialized memory in key_update()
key_update() freed the key_preparsed_payload even if it was not
initialized first.  This would cause a crash if userspace called
keyctl_update() on a key with type like "asymmetric" that has a
->preparse() method but not an ->update() method.  Possibly it could
even be triggered for other key types by racing with keyctl_setperm() to
make the KEY_NEED_WRITE check fail (the permission was already checked,
so normally it wouldn't fail there).

Reproducer with key type "asymmetric", given a valid cert.der:

keyctl new_session
keyid=$(keyctl padd asymmetric desc @s < cert.der)
keyctl setperm $keyid 0x3f000000
keyctl update $keyid data

[  150.686666] BUG: unable to handle kernel NULL pointer dereference at 0000000000000001
[  150.687601] IP: asymmetric_key_free_kids+0x12/0x30
[  150.688139] PGD 38a3d067
[  150.688141] PUD 3b3de067
[  150.688447] PMD 0
[  150.688745]
[  150.689160] Oops: 0000 [#1] SMP
[  150.689455] Modules linked in:
[  150.689769] CPU: 1 PID: 2478 Comm: keyctl Not tainted 4.11.0-rc4-xfstests-00187-ga9f6b6b8cd2f #742
[  150.690916] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-20170228_101828-anatol 04/01/2014
[  150.692199] task: ffff88003b30c480 task.stack: ffffc90000350000
[  150.692952] RIP: 0010:asymmetric_key_free_kids+0x12/0x30
[  150.693556] RSP: 0018:ffffc90000353e58 EFLAGS: 00010202
[  150.694142] RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000004
[  150.694845] RDX: ffffffff81ee3920 RSI: ffff88003d4b0700 RDI: 0000000000000001
[  150.697569] RBP: ffffc90000353e60 R08: ffff88003d5d2140 R09: 0000000000000000
[  150.702483] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
[  150.707393] R13: 0000000000000004 R14: ffff880038a4d2d8 R15: 000000000040411f
[  150.709720] FS:  00007fcbcee35700(0000) GS:ffff88003fd00000(0000) knlGS:0000000000000000
[  150.711504] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  150.712733] CR2: 0000000000000001 CR3: 0000000039eab000 CR4: 00000000003406e0
[  150.714487] Call Trace:
[  150.714975]  asymmetric_key_free_preparse+0x2f/0x40
[  150.715907]  key_update+0xf7/0x140
[  150.716560]  ? key_default_cmp+0x20/0x20
[  150.717319]  keyctl_update_key+0xb0/0xe0
[  150.718066]  SyS_keyctl+0x109/0x130
[  150.718663]  entry_SYSCALL_64_fastpath+0x1f/0xc2
[  150.719440] RIP: 0033:0x7fcbce75ff19
[  150.719926] RSP: 002b:00007ffd5d167088 EFLAGS: 00000206 ORIG_RAX: 00000000000000fa
[  150.720918] RAX: ffffffffffffffda RBX: 0000000000404d80 RCX: 00007fcbce75ff19
[  150.721874] RDX: 00007ffd5d16785e RSI: 000000002866cd36 RDI: 0000000000000002
[  150.722827] RBP: 0000000000000006 R08: 000000002866cd36 R09: 00007ffd5d16785e
[  150.723781] R10: 0000000000000004 R11: 0000000000000206 R12: 0000000000404d80
[  150.724650] R13: 00007ffd5d16784d R14: 00007ffd5d167238 R15: 000000000040411f
[  150.725447] Code: 83 c4 08 31 c0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 85 ff 74 23 55 48 89 e5 53 48 89 fb <48> 8b 3f e8 06 21 c5 ff 48 8b 7b 08 e8 fd 20 c5 ff 48 89 df e8
[  150.727489] RIP: asymmetric_key_free_kids+0x12/0x30 RSP: ffffc90000353e58
[  150.728117] CR2: 0000000000000001
[  150.728430] ---[ end trace f7f8fe1da2d5ae8d ]---

Fixes: 4d8c0250b8 ("KEYS: Call ->free_preparse() even after ->preparse() returns an error")
Cc: stable@vger.kernel.org # 3.17+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:47 +10:00
Eric Biggers
5649645d72 KEYS: fix dereferencing NULL payload with nonzero length
sys_add_key() and the KEYCTL_UPDATE operation of sys_keyctl() allowed a
NULL payload with nonzero length to be passed to the key type's
->preparse(), ->instantiate(), and/or ->update() methods.  Various key
types including asymmetric, cifs.idmap, cifs.spnego, and pkcs7_test did
not handle this case, allowing an unprivileged user to trivially cause a
NULL pointer dereference (kernel oops) if one of these key types was
present.  Fix it by doing the copy_from_user() when 'plen' is nonzero
rather than when '_payload' is non-NULL, causing the syscall to fail
with EFAULT as expected when an invalid buffer is specified.

Cc: stable@vger.kernel.org # 2.6.10+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:47 +10:00
Eric Biggers
0f534e4a13 KEYS: encrypted: use constant-time HMAC comparison
MACs should, in general, be compared using crypto_memneq() to prevent
timing attacks.

Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:47 +10:00
Eric Biggers
64d107d3ac KEYS: encrypted: fix race causing incorrect HMAC calculations
The encrypted-keys module was using a single global HMAC transform,
which could be rekeyed by multiple threads concurrently operating on
different keys, causing incorrect HMAC values to be calculated.  Fix
this by allocating a new HMAC transform whenever we need to calculate a
HMAC.  Also simplify things a bit by allocating the shash_desc's using
SHASH_DESC_ON_STACK() for both the HMAC and unkeyed hashes.

The following script reproduces the bug:

    keyctl new_session
    keyctl add user master "abcdefghijklmnop" @s
    for i in $(seq 2); do
        (
            set -e
            for j in $(seq 1000); do
                keyid=$(keyctl add encrypted desc$i "new user:master 25" @s)
                datablob="$(keyctl pipe $keyid)"
                keyctl unlink $keyid > /dev/null
                keyid=$(keyctl add encrypted desc$i "load $datablob" @s)
                keyctl unlink $keyid > /dev/null
            done
        ) &
    done

Output with bug:

    [  439.691094] encrypted_key: bad hmac (-22)
    add_key: Invalid argument
    add_key: Invalid argument

Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:47 +10:00
Eric Biggers
794b4bc292 KEYS: encrypted: fix buffer overread in valid_master_desc()
With the 'encrypted' key type it was possible for userspace to provide a
data blob ending with a master key description shorter than expected,
e.g. 'keyctl add encrypted desc "new x" @s'.  When validating such a
master key description, validate_master_desc() could read beyond the end
of the buffer.  Fix this by using strncmp() instead of memcmp().  [Also
clean up the code to deduplicate some logic.]

Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:46 +10:00
Eric Biggers
e9ff56ac35 KEYS: encrypted: avoid encrypting/decrypting stack buffers
Since v4.9, the crypto API cannot (normally) be used to encrypt/decrypt
stack buffers because the stack may be virtually mapped.  Fix this for
the padding buffers in encrypted-keys by using ZERO_PAGE for the
encryption padding and by allocating a temporary heap buffer for the
decryption padding.

Tested with CONFIG_DEBUG_SG=y:
	keyctl new_session
	keyctl add user master "abcdefghijklmnop" @s
	keyid=$(keyctl add encrypted desc "new user:master 25" @s)
	datablob="$(keyctl pipe $keyid)"
	keyctl unlink $keyid
	keyid=$(keyctl add encrypted desc "load $datablob" @s)
	datablob2="$(keyctl pipe $keyid)"
	[ "$datablob" = "$datablob2" ] && echo "Success!"

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:46 +10:00
Eric Biggers
d636bd9f12 KEYS: put keyring if install_session_keyring_to_cred() fails
In join_session_keyring(), if install_session_keyring_to_cred() were to
fail, we would leak the keyring reference, just like in the bug fixed by
commit 23567fd052 ("KEYS: Fix keyring ref leak in
join_session_keyring()").  Fortunately this cannot happen currently, but
we really should be more careful.  Do this by adding and using a new
error label at which the keyring reference is dropped.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:46 +10:00
Markus Elfring
41f1c53e0d KEYS: Delete an error message for a failed memory allocation in get_derived_key()
Omit an extra message for a memory allocation failure in this function.

This issue was detected by using the Coccinelle software.

Link: http://events.linuxfoundation.org/sites/events/files/slides/LCJ16-Refactor_Strings-WSang_0.pdf
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:46 +10:00
Davidlohr Bueso
381f20fceb security: use READ_ONCE instead of deprecated ACCESS_ONCE
With the new standardized functions, we can replace all ACCESS_ONCE()
calls across relevant security/keyrings/.

ACCESS_ONCE() does not work reliably on non-scalar types. For example
gcc 4.6 and 4.7 might remove the volatile tag for such accesses during
the SRA (scalar replacement of aggregates) step:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145

Update the new calls regardless of if it is a scalar type, this is
cleaner than having three alternatives.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:45 +10:00
Bilal Amarni
47b2c3fff4 security/keys: add CONFIG_KEYS_COMPAT to Kconfig
CONFIG_KEYS_COMPAT is defined in arch-specific Kconfigs and is missing for
several 64-bit architectures : mips, parisc, tile.

At the moment and for those architectures, calling in 32-bit userspace the
keyctl syscall would return an ENOSYS error.

This patch moves the CONFIG_KEYS_COMPAT option to security/keys/Kconfig, to
make sure the compatibility wrapper is registered by default for any 64-bit
architecture as long as it is configured with CONFIG_COMPAT.

[DH: Modified to remove arm64 compat enablement also as requested by Eric
 Biggers]

Signed-off-by: Bilal Amarni <bilal.amarni@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
cc: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-09 13:29:45 +10:00
Kees Cook
5395d312df doc: ReSTify keys-trusted-encrypted.txt
Adjusts for ReST markup and moves under keys security devel index.

Cc: David Howells <dhowells@redhat.com>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-05-18 10:33:56 -06:00
Kees Cook
3db38ed768 doc: ReSTify keys-request-key.txt
Adjusts for ReST markup and moves under keys security devel index.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-05-18 10:33:51 -06:00
Michal Hocko
752ade68cb treewide: use kv[mz]alloc* rather than opencoded variants
There are many code paths opencoding kvmalloc.  Let's use the helper
instead.  The main difference to kvmalloc is that those users are
usually not considering all the aspects of the memory allocator.  E.g.
allocation requests <= 32kB (with 4kB pages) are basically never failing
and invoke OOM killer to satisfy the allocation.  This sounds too
disruptive for something that has a reasonable fallback - the vmalloc.
On the other hand those requests might fallback to vmalloc even when the
memory allocator would succeed after several more reclaim/compaction
attempts previously.  There is no guarantee something like that happens
though.

This patch converts many of those places to kv[mz]alloc* helpers because
they are more conservative.

Link: http://lkml.kernel.org/r/20170306103327.2766-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> # Xen bits
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Andreas Dilger <andreas.dilger@intel.com> # Lustre
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> # KVM/s390
Acked-by: Dan Williams <dan.j.williams@intel.com> # nvdim
Acked-by: David Sterba <dsterba@suse.com> # btrfs
Acked-by: Ilya Dryomov <idryomov@gmail.com> # Ceph
Acked-by: Tariq Toukan <tariqt@mellanox.com> # mlx4
Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx5
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Santosh Raspatur <santosh@chelsio.com>
Cc: Hariprasad S <hariprasad@chelsio.com>
Cc: Yishai Hadas <yishaih@mellanox.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: "Yan, Zheng" <zyan@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:13 -07:00
Linus Torvalds
0302e28dee Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "Highlights:

  IMA:
   - provide ">" and "<" operators for fowner/uid/euid rules

  KEYS:
   - add a system blacklist keyring

   - add KEYCTL_RESTRICT_KEYRING, exposes keyring link restriction
     functionality to userland via keyctl()

  LSM:
   - harden LSM API with __ro_after_init

   - add prlmit security hook, implement for SELinux

   - revive security_task_alloc hook

  TPM:
   - implement contextual TPM command 'spaces'"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (98 commits)
  tpm: Fix reference count to main device
  tpm_tis: convert to using locality callbacks
  tpm: fix handling of the TPM 2.0 event logs
  tpm_crb: remove a cruft constant
  keys: select CONFIG_CRYPTO when selecting DH / KDF
  apparmor: Make path_max parameter readonly
  apparmor: fix parameters so that the permission test is bypassed at boot
  apparmor: fix invalid reference to index variable of iterator line 836
  apparmor: use SHASH_DESC_ON_STACK
  security/apparmor/lsm.c: set debug messages
  apparmor: fix boolreturn.cocci warnings
  Smack: Use GFP_KERNEL for smk_netlbl_mls().
  smack: fix double free in smack_parse_opts_str()
  KEYS: add SP800-56A KDF support for DH
  KEYS: Keyring asymmetric key restrict method with chaining
  KEYS: Restrict asymmetric key linkage using a specific keychain
  KEYS: Add a lookup_restriction function for the asymmetric key type
  KEYS: Add KEYCTL_RESTRICT_KEYRING
  KEYS: Consistent ordering for __key_link_begin and restrict check
  KEYS: Add an optional lookup_restriction hook to key_type
  ...
2017-05-03 08:50:52 -07:00
Eric Biggers
c9f838d104 KEYS: fix keyctl_set_reqkey_keyring() to not leak thread keyrings
This fixes CVE-2017-7472.

Running the following program as an unprivileged user exhausts kernel
memory by leaking thread keyrings:

	#include <keyutils.h>

	int main()
	{
		for (;;)
			keyctl_set_reqkey_keyring(KEY_REQKEY_DEFL_THREAD_KEYRING);
	}

Fix it by only creating a new thread keyring if there wasn't one before.
To make things more consistent, make install_thread_keyring_to_cred()
and install_process_keyring_to_cred() both return 0 if the corresponding
keyring is already present.

Fixes: d84f4f992c ("CRED: Inaugurate COW credentials")
Cc: stable@vger.kernel.org # 2.6.29+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-04-18 15:31:49 +01:00
David Howells
c1644fe041 KEYS: Change the name of the dead type to ".dead" to prevent user access
This fixes CVE-2017-6951.

Userspace should not be able to do things with the "dead" key type as it
doesn't have some of the helper functions set upon it that the kernel
needs.  Attempting to use it may cause the kernel to crash.

Fix this by changing the name of the type to ".dead" so that it's rejected
up front on userspace syscalls by key_get_type_from_user().

Though this doesn't seem to affect recent kernels, it does affect older
ones, certainly those prior to:

	commit c06cfb08b8
	Author: David Howells <dhowells@redhat.com>
	Date:   Tue Sep 16 17:36:06 2014 +0100
	KEYS: Remove key_type::match in favour of overriding default by match_preparse

which went in before 3.18-rc1.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: stable@vger.kernel.org
2017-04-18 15:31:39 +01:00
David Howells
ee8f844e3c KEYS: Disallow keyrings beginning with '.' to be joined as session keyrings
This fixes CVE-2016-9604.

Keyrings whose name begin with a '.' are special internal keyrings and so
userspace isn't allowed to create keyrings by this name to prevent
shadowing.  However, the patch that added the guard didn't fix
KEYCTL_JOIN_SESSION_KEYRING.  Not only can that create dot-named keyrings,
it can also subscribe to them as a session keyring if they grant SEARCH
permission to the user.

This, for example, allows a root process to set .builtin_trusted_keys as
its session keyring, at which point it has full access because now the
possessor permissions are added.  This permits root to add extra public
keys, thereby bypassing module verification.

This also affects kexec and IMA.

This can be tested by (as root):

	keyctl session .builtin_trusted_keys
	keyctl add user a a @s
	keyctl list @s

which on my test box gives me:

	2 keys in keyring:
	180010936: ---lswrv     0     0 asymmetric: Build time autogenerated kernel key: ae3d4a31b82daa8e1a75b49dc2bba949fd992a05
	801382539: --alswrv     0     0 user: a


Fix this by rejecting names beginning with a '.' in the keyctl.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
cc: linux-ima-devel@lists.sourceforge.net
cc: stable@vger.kernel.org
2017-04-18 15:31:35 +01:00
Stephan Müller
4cd4ca7cc8 keys: select CONFIG_CRYPTO when selecting DH / KDF
Select CONFIG_CRYPTO in addition to CONFIG_HASH to ensure that
also CONFIG_HASH2 is selected. Both are needed for the shash
cipher support required for the KDF operation.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-04-11 23:18:09 +01:00
Stephan Mueller
f1c316a3ab KEYS: add SP800-56A KDF support for DH
SP800-56A defines the use of DH with key derivation function based on a
counter. The input to the KDF is defined as (DH shared secret || other
information). The value for the "other information" is to be provided by
the caller.

The KDF is implemented using the hash support from the kernel crypto API.
The implementation uses the symmetric hash support as the input to the
hash operation is usually very small. The caller is allowed to specify
the hash name that he wants to use to derive the key material allowing
the use of all supported hashes provided with the kernel crypto API.

As the KDF implements the proper truncation of the DH shared secret to
the requested size, this patch fills the caller buffer up to its size.

The patch is tested with a new test added to the keyutils user space
code which uses a CAVS test vector testing the compliance with
SP800-56A.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-04-04 22:33:38 +01:00
Mat Martineau
6563c91fd6 KEYS: Add KEYCTL_RESTRICT_KEYRING
Keyrings recently gained restrict_link capabilities that allow
individual keys to be validated prior to linking.  This functionality
was only available using internal kernel APIs.

With the KEYCTL_RESTRICT_KEYRING command existing keyrings can be
configured to check the content of keys before they are linked, and
then allow or disallow linkage of that key to the keyring.

To restrict a keyring, call:

  keyctl(KEYCTL_RESTRICT_KEYRING, key_serial_t keyring, const char *type,
         const char *restriction)

where 'type' is the name of a registered key type and 'restriction' is a
string describing how key linkage is to be restricted. The restriction
option syntax is specific to each key type.

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
2017-04-04 14:10:12 -07:00
Mat Martineau
4a420896f1 KEYS: Consistent ordering for __key_link_begin and restrict check
The keyring restrict callback was sometimes called before
__key_link_begin and sometimes after, which meant that the keyring
semaphores were not always held during the restrict callback.

If the semaphores are consistently acquired before checking link
restrictions, keyring contents cannot be changed after the restrict
check is complete but before the evaluated key is linked to the keyring.

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
2017-04-04 14:10:11 -07:00
Mat Martineau
2b6aa412ff KEYS: Use structure to capture key restriction function and data
Replace struct key's restrict_link function pointer with a pointer to
the new struct key_restriction. The structure contains pointers to the
restriction function as well as relevant data for evaluating the
restriction.

The garbage collector checks restrict_link->keytype when key types are
unregistered. Restrictions involving a removed key type are converted
to use restrict_link_reject so that restrictions cannot be removed by
unregistering key types.

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
2017-04-04 14:10:10 -07:00
Mat Martineau
aaf66c8838 KEYS: Split role of the keyring pointer for keyring restrict functions
The first argument to the restrict_link_func_t functions was a keyring
pointer. These functions are called by the key subsystem with this
argument set to the destination keyring, but restrict_link_by_signature
expects a pointer to the relevant trusted keyring.

Restrict functions may need something other than a single struct key
pointer to allow or reject key linkage, so the data used to make that
decision (such as the trust keyring) is moved to a new, fourth
argument. The first argument is now always the destination keyring.

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
2017-04-03 10:24:56 -07:00
Mat Martineau
469ff8f7d4 KEYS: Use a typedef for restrict_link function pointers
This pointer type needs to be returned from a lookup function, and
without a typedef the syntax gets cumbersome.

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
2017-04-03 10:24:55 -07:00
Elena Reshetova
ddb99e118e security, keys: convert key_user.usage from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-04-03 10:49:06 +10:00
Elena Reshetova
fff292914d security, keys: convert key.usage from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-04-03 10:49:05 +10:00
Linus Torvalds
1827adb11a Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull sched.h split-up from Ingo Molnar:
 "The point of these changes is to significantly reduce the
  <linux/sched.h> header footprint, to speed up the kernel build and to
  have a cleaner header structure.

  After these changes the new <linux/sched.h>'s typical preprocessed
  size goes down from a previous ~0.68 MB (~22K lines) to ~0.45 MB (~15K
  lines), which is around 40% faster to build on typical configs.

  Not much changed from the last version (-v2) posted three weeks ago: I
  eliminated quirks, backmerged fixes plus I rebased it to an upstream
  SHA1 from yesterday that includes most changes queued up in -next plus
  all sched.h changes that were pending from Andrew.

  I've re-tested the series both on x86 and on cross-arch defconfigs,
  and did a bisectability test at a number of random points.

  I tried to test as many build configurations as possible, but some
  build breakage is probably still left - but it should be mostly
  limited to architectures that have no cross-compiler binaries
  available on kernel.org, and non-default configurations"

* 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (146 commits)
  sched/headers: Clean up <linux/sched.h>
  sched/headers: Remove #ifdefs from <linux/sched.h>
  sched/headers: Remove the <linux/topology.h> include from <linux/sched.h>
  sched/headers, hrtimer: Remove the <linux/wait.h> include from <linux/hrtimer.h>
  sched/headers, x86/apic: Remove the <linux/pm.h> header inclusion from <asm/apic.h>
  sched/headers, timers: Remove the <linux/sysctl.h> include from <linux/timer.h>
  sched/headers: Remove <linux/magic.h> from <linux/sched/task_stack.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/init.h>
  sched/core: Remove unused prefetch_stack()
  sched/headers: Remove <linux/rculist.h> from <linux/sched.h>
  sched/headers: Remove the 'init_pid_ns' prototype from <linux/sched.h>
  sched/headers: Remove <linux/signal.h> from <linux/sched.h>
  sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>
  sched/headers: Remove the runqueue_is_locked() prototype
  sched/headers: Remove <linux/sched.h> from <linux/sched/hotplug.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/debug.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/nohz.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/stat.h>
  sched/headers: Remove the <linux/gfp.h> include from <linux/sched.h>
  sched/headers: Remove <linux/rtmutex.h> from <linux/sched.h>
  ...
2017-03-03 10:16:38 -08:00
Ingo Molnar
299300258d sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>
We are going to split <linux/sched/task.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/task.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:35 +01:00
Ingo Molnar
5b825c3af1 sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>
Add #include <linux/cred.h> dependencies to all .c files rely on sched.h
doing that for them.

Note that even if the count where we need to add extra headers seems high,
it's still a net win, because <linux/sched.h> is included in over
2,200 files ...

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:31 +01:00
Ingo Molnar
8703e8a465 sched/headers: Prepare for new header dependencies before moving code to <linux/sched/user.h>
We are going to split <linux/sched/user.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/user.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:29 +01:00
David Howells
0837e49ab3 KEYS: Differentiate uses of rcu_dereference_key() and user_key_payload()
rcu_dereference_key() and user_key_payload() are currently being used in
two different, incompatible ways:

 (1) As a wrapper to rcu_dereference() - when only the RCU read lock used
     to protect the key.

 (2) As a wrapper to rcu_dereference_protected() - when the key semaphor is
     used to protect the key and the may be being modified.

Fix this by splitting both of the key wrappers to produce:

 (1) RCU accessors for keys when caller has the key semaphore locked:

	dereference_key_locked()
	user_key_payload_locked()

 (2) RCU accessors for keys when caller holds the RCU read lock:

	dereference_key_rcu()
	user_key_payload_rcu()

This should fix following warning in the NFS idmapper

  ===============================
  [ INFO: suspicious RCU usage. ]
  4.10.0 #1 Tainted: G        W
  -------------------------------
  ./include/keys/user-type.h:53 suspicious rcu_dereference_protected() usage!
  other info that might help us debug this:
  rcu_scheduler_active = 2, debug_locks = 0
  1 lock held by mount.nfs/5987:
    #0:  (rcu_read_lock){......}, at: [<d000000002527abc>] nfs_idmap_get_key+0x15c/0x420 [nfsv4]
  stack backtrace:
  CPU: 1 PID: 5987 Comm: mount.nfs Tainted: G        W       4.10.0 #1
  Call Trace:
    dump_stack+0xe8/0x154 (unreliable)
    lockdep_rcu_suspicious+0x140/0x190
    nfs_idmap_get_key+0x380/0x420 [nfsv4]
    nfs_map_name_to_uid+0x2a0/0x3b0 [nfsv4]
    decode_getfattr_attrs+0xfac/0x16b0 [nfsv4]
    decode_getfattr_generic.constprop.106+0xbc/0x150 [nfsv4]
    nfs4_xdr_dec_lookup_root+0xac/0xb0 [nfsv4]
    rpcauth_unwrap_resp+0xe8/0x140 [sunrpc]
    call_decode+0x29c/0x910 [sunrpc]
    __rpc_execute+0x140/0x8f0 [sunrpc]
    rpc_run_task+0x170/0x200 [sunrpc]
    nfs4_call_sync_sequence+0x68/0xa0 [nfsv4]
    _nfs4_lookup_root.isra.44+0xd0/0xf0 [nfsv4]
    nfs4_lookup_root+0xe0/0x350 [nfsv4]
    nfs4_lookup_root_sec+0x70/0xa0 [nfsv4]
    nfs4_find_root_sec+0xc4/0x100 [nfsv4]
    nfs4_proc_get_rootfh+0x5c/0xf0 [nfsv4]
    nfs4_get_rootfh+0x6c/0x190 [nfsv4]
    nfs4_server_common_setup+0xc4/0x260 [nfsv4]
    nfs4_create_server+0x278/0x3c0 [nfsv4]
    nfs4_remote_mount+0x50/0xb0 [nfsv4]
    mount_fs+0x74/0x210
    vfs_kern_mount+0x78/0x220
    nfs_do_root_mount+0xb0/0x140 [nfsv4]
    nfs4_try_mount+0x60/0x100 [nfsv4]
    nfs_fs_mount+0x5ec/0xda0 [nfs]
    mount_fs+0x74/0x210
    vfs_kern_mount+0x78/0x220
    do_mount+0x254/0xf70
    SyS_mount+0x94/0x100
    system_call+0x38/0xe0

Reported-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-03-02 10:09:00 +11:00
Linus Torvalds
b2064617c7 driver core patches for 4.11-rc1
Here is the "small" driver core patches for 4.11-rc1.
 
 Not much here, some firmware documentation and self-test updates, a
 debugfs code formatting issue, and a new feature for call_usermodehelper
 to make it more robust on systems that want to lock it down in a more
 secure way.
 
 All of these have been linux-next for a while now with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCWK2jKg8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ymCEACgozYuqZZ/TUGW0P3xVNi7fbfUWCEAn3nYExrc
 XgevqeYOSKp2We6X/2JX
 =aZ+5
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the "small" driver core patches for 4.11-rc1.

  Not much here, some firmware documentation and self-test updates, a
  debugfs code formatting issue, and a new feature for call_usermodehelper
  to make it more robust on systems that want to lock it down in a more
  secure way.

  All of these have been linux-next for a while now with no reported
  issues"

* tag 'driver-core-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  kernfs: handle null pointers while printing node name and path
  Introduce STATIC_USERMODEHELPER to mediate call_usermodehelper()
  Make static usermode helper binaries constant
  kmod: make usermodehelper path a const string
  firmware: revamp firmware documentation
  selftests: firmware: send expected errors to /dev/null
  selftests: firmware: only modprobe if driver is missing
  platform: Print the resource range if device failed to claim
  kref: prefer atomic_inc_not_zero to atomic_add_unless
  debugfs: improve formatting of debugfs_real_fops()
2017-02-22 11:44:32 -08:00
Dan Carpenter
5217660379 KEYS: Use memzero_explicit() for secret data
I don't think GCC has figured out how to optimize the memset() away, but
they might eventually so let's future proof this code a bit.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-02-10 12:43:51 +11:00
Dan Carpenter
57cb17e764 KEYS: Fix an error code in request_master_key()
This function has two callers and neither are able to handle a NULL
return.  Really, -EINVAL is the correct thing return here anyway.  This
fixes some static checker warnings like:

	security/keys/encrypted-keys/encrypted.c:709 encrypted_key_decrypt()
	error: uninitialized symbol 'master_key'.

Fixes: 7e70cb4978 ("keys: add new key-type encrypted")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-02-10 12:43:49 +11:00
Greg Kroah-Hartman
377e7a27c0 Make static usermode helper binaries constant
There are a number of usermode helper binaries that are "hard coded" in
the kernel today, so mark them as "const" to make it harder for someone
to change where the variables point to.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Sailer <t.sailer@alumni.ethz.ch>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alex Elder <elder@kernel.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 12:59:45 +01:00
Linus Torvalds
7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Al Viro
cbbd26b8b1 [iov_iter] new primitives - copy_from_iter_full() and friends
copy_from_iter_full(), copy_from_iter_full_nocache() and
csum_and_copy_from_iter_full() - counterparts of copy_from_iter()
et.al., advancing iterator only in case of successful full copy
and returning whether it had been successful or not.

Convert some obvious users.  *NOTE* - do not blindly assume that
something is a good candidate for those unless you are sure that
not advancing iov_iter in failure case is the right thing in
this case.  Anything that does short read/short write kind of
stuff (or is in a loop, etc.) is unlikely to be a good one.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-05 14:33:36 -05:00
Artem Savkov
31e6ec4519 security/keys: make BIG_KEYS dependent on stdrng.
Since BIG_KEYS can't be compiled as module it requires one of the "stdrng"
providers to be compiled into kernel. Otherwise big_key_crypto_init() fails
on crypto_alloc_rng step and next dereference of big_key_skcipher (e.g. in
big_key_preparse()) results in a NULL pointer dereference.

Fixes: 13100a72f4 ('Security: Keys: Big keys stored encrypted')
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Stephan Mueller <smueller@chronox.de>
cc: Kirill Marinushkin <k.marinushkin@gmail.com>
cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-10-27 16:03:33 +11:00
David Howells
7df3e59c3d KEYS: Sort out big_key initialisation
big_key has two separate initialisation functions, one that registers the
key type and one that registers the crypto.  If the key type fails to
register, there's no problem if the crypto registers successfully because
there's no way to reach the crypto except through the key type.

However, if the key type registers successfully but the crypto does not,
big_key_rng and big_key_blkcipher may end up set to NULL - but the code
neither checks for this nor unregisters the big key key type.

Furthermore, since the key type is registered before the crypto, it is
theoretically possible for the kernel to try adding a big_key before the
crypto is set up, leading to the same effect.

Fix this by merging big_key_crypto_init() and big_key_init() and calling
the resulting function late.  If they're going to be encrypted, we
shouldn't be creating big_keys before we have the facilities to do the
encryption available.  The key type registration is also moved after the
crypto initialisation.

The fix also includes message printing on failure.

If the big_key type isn't correctly set up, simply doing:

	dd if=/dev/zero bs=4096 count=1 | keyctl padd big_key a @s

ought to cause an oops.

Fixes: 13100a72f4 ('Security: Keys: Big keys stored encrypted')
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Peter Hlavaty <zer0mem@yahoo.com>
cc: Kirill Marinushkin <k.marinushkin@gmail.com>
cc: Artem Savkov <asavkov@redhat.com>
cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-10-27 16:03:27 +11:00
David Howells
03dab869b7 KEYS: Fix short sprintf buffer in /proc/keys show function
This fixes CVE-2016-7042.

Fix a short sprintf buffer in proc_keys_show().  If the gcc stack protector
is turned on, this can cause a panic due to stack corruption.

The problem is that xbuf[] is not big enough to hold a 64-bit timeout
rendered as weeks:

	(gdb) p 0xffffffffffffffffULL/(60*60*24*7)
	$2 = 30500568904943

That's 14 chars plus NUL, not 11 chars plus NUL.

Expand the buffer to 16 chars.

I think the unpatched code apparently works if the stack-protector is not
enabled because on a 32-bit machine the buffer won't be overflowed and on a
64-bit machine there's a 64-bit aligned pointer at one side and an int that
isn't checked again on the other side.

The panic incurred looks something like:

Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffff81352ebe
CPU: 0 PID: 1692 Comm: reproducer Not tainted 4.7.2-201.fc24.x86_64 #1
Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
 0000000000000086 00000000fbbd2679 ffff8800a044bc00 ffffffff813d941f
 ffffffff81a28d58 ffff8800a044bc98 ffff8800a044bc88 ffffffff811b2cb6
 ffff880000000010 ffff8800a044bc98 ffff8800a044bc30 00000000fbbd2679
Call Trace:
 [<ffffffff813d941f>] dump_stack+0x63/0x84
 [<ffffffff811b2cb6>] panic+0xde/0x22a
 [<ffffffff81352ebe>] ? proc_keys_show+0x3ce/0x3d0
 [<ffffffff8109f7f9>] __stack_chk_fail+0x19/0x30
 [<ffffffff81352ebe>] proc_keys_show+0x3ce/0x3d0
 [<ffffffff81350410>] ? key_validate+0x50/0x50
 [<ffffffff8134db30>] ? key_default_cmp+0x20/0x20
 [<ffffffff8126b31c>] seq_read+0x2cc/0x390
 [<ffffffff812b6b12>] proc_reg_read+0x42/0x70
 [<ffffffff81244fc7>] __vfs_read+0x37/0x150
 [<ffffffff81357020>] ? security_file_permission+0xa0/0xc0
 [<ffffffff81246156>] vfs_read+0x96/0x130
 [<ffffffff81247635>] SyS_read+0x55/0xc0
 [<ffffffff817eb872>] entry_SYSCALL_64_fastpath+0x1a/0xa4

Reported-by: Ondrej Kozina <okozina@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Ondrej Kozina <okozina@redhat.com>
cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-10-27 16:03:24 +11:00
Herbert Xu
456bee986e KEYS: Fix skcipher IV clobbering
The IV must not be modified by the skcipher operation so we need
to duplicate it.

Fixes: c3917fd9df ("KEYS: Use skcipher")
Cc: stable@vger.kernel.org
Reported-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-09-22 17:42:07 +08:00
Linus Torvalds
7a1e8b80fb Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "Highlights:

   - TPM core and driver updates/fixes
   - IPv6 security labeling (CALIPSO)
   - Lots of Apparmor fixes
   - Seccomp: remove 2-phase API, close hole where ptrace can change
     syscall #"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (156 commits)
  apparmor: fix SECURITY_APPARMOR_HASH_DEFAULT parameter handling
  tpm: Add TPM 2.0 support to the Nuvoton i2c driver (NPCT6xx family)
  tpm: Factor out common startup code
  tpm: use devm_add_action_or_reset
  tpm2_i2c_nuvoton: add irq validity check
  tpm: read burstcount from TPM_STS in one 32-bit transaction
  tpm: fix byte-order for the value read by tpm2_get_tpm_pt
  tpm_tis_core: convert max timeouts from msec to jiffies
  apparmor: fix arg_size computation for when setprocattr is null terminated
  apparmor: fix oops, validate buffer size in apparmor_setprocattr()
  apparmor: do not expose kernel stack
  apparmor: fix module parameters can be changed after policy is locked
  apparmor: fix oops in profile_unpack() when policy_db is not present
  apparmor: don't check for vmalloc_addr if kvzalloc() failed
  apparmor: add missing id bounds check on dfa verification
  apparmor: allow SYS_CAP_RESOURCE to be sufficient to prlimit another task
  apparmor: use list_next_entry instead of list_entry_next
  apparmor: fix refcount race when finding a child profile
  apparmor: fix ref count leak when profile sha1 hash is read
  apparmor: check that xindex is in trans_table bounds
  ...
2016-07-29 17:38:46 -07:00
Linus Torvalds
bbce2ad2d7 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "Here is the crypto update for 4.8:

  API:
   - first part of skcipher low-level conversions
   - add KPP (Key-agreement Protocol Primitives) interface.

  Algorithms:
   - fix IPsec/cryptd reordering issues that affects aesni
   - RSA no longer does explicit leading zero removal
   - add SHA3
   - add DH
   - add ECDH
   - improve DRBG performance by not doing CTR by hand

  Drivers:
   - add x86 AVX2 multibuffer SHA256/512
   - add POWER8 optimised crc32c
   - add xts support to vmx
   - add DH support to qat
   - add RSA support to caam
   - add Layerscape support to caam
   - add SEC1 AEAD support to talitos
   - improve performance by chaining requests in marvell/cesa
   - add support for Araneus Alea I USB RNG
   - add support for Broadcom BCM5301 RNG
   - add support for Amlogic Meson RNG
   - add support Broadcom NSP SoC RNG"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (180 commits)
  crypto: vmx - Fix aes_p8_xts_decrypt build failure
  crypto: vmx - Ignore generated files
  crypto: vmx - Adding support for XTS
  crypto: vmx - Adding asm subroutines for XTS
  crypto: skcipher - add comment for skcipher_alg->base
  crypto: testmgr - Print akcipher algorithm name
  crypto: marvell - Fix wrong flag used for GFP in mv_cesa_dma_add_iv_op
  crypto: nx - off by one bug in nx_of_update_msc()
  crypto: rsa-pkcs1pad - fix rsa-pkcs1pad request struct
  crypto: scatterwalk - Inline start/map/done
  crypto: scatterwalk - Remove unnecessary BUG in scatterwalk_start
  crypto: scatterwalk - Remove unnecessary advance in scatterwalk_pagedone
  crypto: scatterwalk - Fix test in scatterwalk_done
  crypto: api - Optimise away crypto_yield when hard preemption is on
  crypto: scatterwalk - add no-copy support to copychunks
  crypto: scatterwalk - Remove scatterwalk_bytes_sglen
  crypto: omap - Stop using crypto scatterwalk_bytes_sglen
  crypto: skcipher - Remove top-level givcipher interface
  crypto: user - Remove crypto_lookup_skcipher call
  crypto: cts - Convert to skcipher
  ...
2016-07-26 13:40:17 -07:00
Herbert Xu
d56d72c6a0 KEYS: Use skcipher for big keys
This patch replaces use of the obsolete blkcipher with skcipher.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: David Howells <dhowells@redhat.com>
2016-06-24 21:24:58 +08:00
Dan Carpenter
38327424b4 KEYS: potential uninitialized variable
If __key_link_begin() failed then "edit" would be uninitialized.  I've
added a check to fix that.

This allows a random user to crash the kernel, though it's quite
difficult to achieve.  There are three ways it can be done as the user
would have to cause an error to occur in __key_link():

 (1) Cause the kernel to run out of memory.  In practice, this is difficult
     to achieve without ENOMEM cropping up elsewhere and aborting the
     attempt.

 (2) Revoke the destination keyring between the keyring ID being looked up
     and it being tested for revocation.  In practice, this is difficult to
     time correctly because the KEYCTL_REJECT function can only be used
     from the request-key upcall process.  Further, users can only make use
     of what's in /sbin/request-key.conf, though this does including a
     rejection debugging test - which means that the destination keyring
     has to be the caller's session keyring in practice.

 (3) Have just enough key quota available to create a key, a new session
     keyring for the upcall and a link in the session keyring, but not then
     sufficient quota to create a link in the nominated destination keyring
     so that it fails with EDQUOT.

The bug can be triggered using option (3) above using something like the
following:

	echo 80 >/proc/sys/kernel/keys/root_maxbytes
	keyctl request2 user debug:fred negate @t

The above sets the quota to something much lower (80) to make the bug
easier to trigger, but this is dependent on the system.  Note also that
the name of the keyring created contains a random number that may be
between 1 and 10 characters in size, so may throw the test off by
changing the amount of quota used.

Assuming the failure occurs, something like the following will be seen:

	kfree_debugcheck: out of range ptr 6b6b6b6b6b6b6b68h
	------------[ cut here ]------------
	kernel BUG at ../mm/slab.c:2821!
	...
	RIP: 0010:[<ffffffff811600f9>] kfree_debugcheck+0x20/0x25
	RSP: 0018:ffff8804014a7de8  EFLAGS: 00010092
	RAX: 0000000000000034 RBX: 6b6b6b6b6b6b6b68 RCX: 0000000000000000
	RDX: 0000000000040001 RSI: 00000000000000f6 RDI: 0000000000000300
	RBP: ffff8804014a7df0 R08: 0000000000000001 R09: 0000000000000000
	R10: ffff8804014a7e68 R11: 0000000000000054 R12: 0000000000000202
	R13: ffffffff81318a66 R14: 0000000000000000 R15: 0000000000000001
	...
	Call Trace:
	  kfree+0xde/0x1bc
	  assoc_array_cancel_edit+0x1f/0x36
	  __key_link_end+0x55/0x63
	  key_reject_and_link+0x124/0x155
	  keyctl_reject_key+0xb6/0xe0
	  keyctl_negate_key+0x10/0x12
	  SyS_keyctl+0x9f/0xe7
	  do_syscall_64+0x63/0x13a
	  entry_SYSCALL64_slow_path+0x25/0x25

Fixes: f70e2e0619 ('KEYS: Do preallocation for __key_link()')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-16 17:15:04 -10:00
David Howells
965475acca KEYS: Strip trailing spaces
Strip some trailing spaces.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-06-14 10:29:44 +01:00
Stephan Mueller
4693fc734d KEYS: Add placeholder for KDF usage with DH
The values computed during Diffie-Hellman key exchange are often used
in combination with key derivation functions to create cryptographic
keys.  Add a placeholder for a later implementation to configure a
key derivation function that will transform the Diffie-Hellman
result returned by the KEYCTL_DH_COMPUTE command.

[This patch was stripped down from a patch produced by Mat Martineau that
 had a bug in the compat code - so for the moment Stephan's patch simply
 requires that the placeholder argument must be NULL]

Original-signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-06-03 16:14:34 +10:00
David Howells
d55201ce08 Merge branch 'keys-trust' into keys-next
Here's a set of patches that changes how certificates/keys are determined
to be trusted.  That's currently a two-step process:

 (1) Up until recently, when an X.509 certificate was parsed - no matter
     the source - it was judged against the keys in .system_keyring,
     assuming those keys to be trusted if they have KEY_FLAG_TRUSTED set
     upon them.

     This has just been changed such that any key in the .ima_mok keyring,
     if configured, may also be used to judge the trustworthiness of a new
     certificate, whether or not the .ima_mok keyring is meant to be
     consulted for whatever process is being undertaken.

     If a certificate is determined to be trustworthy, KEY_FLAG_TRUSTED
     will be set upon a key it is loaded into (if it is loaded into one),
     no matter what the key is going to be loaded for.

 (2) If an X.509 certificate is loaded into a key, then that key - if
     KEY_FLAG_TRUSTED gets set upon it - can be linked into any keyring
     with KEY_FLAG_TRUSTED_ONLY set upon it.  This was meant to be the
     system keyring only, but has been extended to various IMA keyrings.
     A user can at will link any key marked KEY_FLAG_TRUSTED into any
     keyring marked KEY_FLAG_TRUSTED_ONLY if the relevant permissions masks
     permit it.

These patches change that:

 (1) Trust becomes a matter of consulting the ring of trusted keys supplied
     when the trust is evaluated only.

 (2) Every keyring can be supplied with its own manager function to
     restrict what may be added to that keyring.  This is called whenever a
     key is to be linked into the keyring to guard against a key being
     created in one keyring and then linked across.

     This function is supplied with the keyring and the key type and
     payload[*] of the key being linked in for use in its evaluation.  It
     is permitted to use other data also, such as the contents of other
     keyrings such as the system keyrings.

     [*] The type and payload are supplied instead of a key because as an
         optimisation this function may be called whilst creating a key and
         so may reject the proposed key between preparse and allocation.

 (3) A default manager function is provided that permits keys to be
     restricted to only asymmetric keys that are vouched for by the
     contents of the system keyring.

     A second manager function is provided that just rejects with EPERM.

 (4) A key allocation flag, KEY_ALLOC_BYPASS_RESTRICTION, is made available
     so that the kernel can initialise keyrings with keys that form the
     root of the trust relationship.

 (5) KEY_FLAG_TRUSTED and KEY_FLAG_TRUSTED_ONLY are removed, along with
     key_preparsed_payload::trusted.

This change also makes it possible in future for userspace to create a private
set of trusted keys and then to have it sealed by setting a manager function
where the private set is wholly independent of the kernel's trust
relationships.

Further changes in the set involve extracting certain IMA special keyrings
and making them generally global:

 (*) .system_keyring is renamed to .builtin_trusted_keys and remains read
     only.  It carries only keys built in to the kernel.  It may be where
     UEFI keys should be loaded - though that could better be the new
     secondary keyring (see below) or a separate UEFI keyring.

 (*) An optional secondary system keyring (called .secondary_trusted_keys)
     is added to replace the IMA MOK keyring.

     (*) Keys can be added to the secondary keyring by root if the keys can
         be vouched for by either ring of system keys.

 (*) Module signing and kexec only use .builtin_trusted_keys and do not use
     the new secondary keyring.

 (*) Config option SYSTEM_TRUSTED_KEYS now depends on ASYMMETRIC_KEY_TYPE as
     that's the only type currently permitted on the system keyrings.

 (*) A new config option, IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY,
     is provided to allow keys to be added to IMA keyrings, subject to the
     restriction that such keys are validly signed by a key already in the
     system keyrings.

     If this option is enabled, but secondary keyrings aren't, additions to
     the IMA keyrings will be restricted to signatures verifiable by keys in
     the builtin system keyring only.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-05-04 17:20:20 +01:00
Mat Martineau
ddbb411487 KEYS: Add KEYCTL_DH_COMPUTE command
This adds userspace access to Diffie-Hellman computations through a
new keyctl() syscall command to calculate shared secrets or public
keys using input parameters stored in the keyring.

Input key ids are provided in a struct due to the current 5-arg limit
for the keyctl syscall. Only user keys are supported in order to avoid
exposing the content of logon or encrypted keys.

The output is written to the provided buffer, based on the assumption
that the values are only needed in userspace.

Future support for other types of key derivation would involve a new
command, like KEYCTL_ECDH_COMPUTE.

Once Diffie-Hellman support is included in the crypto API, this code
can be converted to use the crypto API to take advantage of possible
hardware acceleration and reduce redundant code.

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-12 19:54:58 +01:00
Kirill Marinushkin
13100a72f4 Security: Keys: Big keys stored encrypted
Solved TODO task: big keys saved to shmem file are now stored encrypted.
The encryption key is randomly generated and saved to payload[big_key_data].

Signed-off-by: Kirill Marinushkin <k.marinushkin@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-12 19:54:58 +01:00
David Howells
898de7d0f2 KEYS: user_update should use copy of payload made during preparsing
The payload preparsing routine for user keys makes a copy of the payload
provided by the caller and stashes it in the key_preparsed_payload struct for
->instantiate() or ->update() to use.  However, ->update() takes another copy
of this to attach to the keyring.  ->update() should be using this directly
and clearing the pointer in the preparse data.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-12 19:54:58 +01:00
David Howells
77f68bac94 KEYS: Remove KEY_FLAG_TRUSTED and KEY_ALLOC_TRUSTED
Remove KEY_FLAG_TRUSTED and KEY_ALLOC_TRUSTED as they're no longer
meaningful.  Also we can drop the trusted flag from the preparse structure.

Given this, we no longer need to pass the key flags through to
restrict_link().

Further, we can now get rid of keyring_restrict_trusted_only() also.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-11 22:44:15 +01:00
David Howells
5ac7eace2d KEYS: Add a facility to restrict new links into a keyring
Add a facility whereby proposed new links to be added to a keyring can be
vetted, permitting them to be rejected if necessary.  This can be used to
block public keys from which the signature cannot be verified or for which
the signature verification fails.  It could also be used to provide
blacklisting.

This affects operations like add_key(), KEYCTL_LINK and KEYCTL_INSTANTIATE.

To this end:

 (1) A function pointer is added to the key struct that, if set, points to
     the vetting function.  This is called as:

	int (*restrict_link)(struct key *keyring,
			     const struct key_type *key_type,
			     unsigned long key_flags,
			     const union key_payload *key_payload),

     where 'keyring' will be the keyring being added to, key_type and
     key_payload will describe the key being added and key_flags[*] can be
     AND'ed with KEY_FLAG_TRUSTED.

     [*] This parameter will be removed in a later patch when
     	 KEY_FLAG_TRUSTED is removed.

     The function should return 0 to allow the link to take place or an
     error (typically -ENOKEY, -ENOPKG or -EKEYREJECTED) to reject the
     link.

     The pointer should not be set directly, but rather should be set
     through keyring_alloc().

     Note that if called during add_key(), preparse is called before this
     method, but a key isn't actually allocated until after this function
     is called.

 (2) KEY_ALLOC_BYPASS_RESTRICTION is added.  This can be passed to
     key_create_or_update() or key_instantiate_and_link() to bypass the
     restriction check.

 (3) KEY_FLAG_TRUSTED_ONLY is removed.  The entire contents of a keyring
     with this restriction emplaced can be considered 'trustworthy' by
     virtue of being in the keyring when that keyring is consulted.

 (4) key_alloc() and keyring_alloc() take an extra argument that will be
     used to set restrict_link in the new key.  This ensures that the
     pointer is set before the key is published, thus preventing a window
     of unrestrictedness.  Normally this argument will be NULL.

 (5) As a temporary affair, keyring_restrict_trusted_only() is added.  It
     should be passed to keyring_alloc() as the extra argument instead of
     setting KEY_FLAG_TRUSTED_ONLY on a keyring.  This will be replaced in
     a later patch with functions that look in the appropriate places for
     authoritative keys.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2016-04-11 22:37:37 +01:00
Linus Torvalds
bb7aeae3d6 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security layer updates from James Morris:
 "There are a bunch of fixes to the TPM, IMA, and Keys code, with minor
  fixes scattered across the subsystem.

  IMA now requires signed policy, and that policy is also now measured
  and appraised"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (67 commits)
  X.509: Make algo identifiers text instead of enum
  akcipher: Move the RSA DER encoding check to the crypto layer
  crypto: Add hash param to pkcs1pad
  sign-file: fix build with CMS support disabled
  MAINTAINERS: update tpmdd urls
  MODSIGN: linux/string.h should be #included to get memcpy()
  certs: Fix misaligned data in extra certificate list
  X.509: Handle midnight alternative notation in GeneralizedTime
  X.509: Support leap seconds
  Handle ISO 8601 leap seconds and encodings of midnight in mktime64()
  X.509: Fix leap year handling again
  PKCS#7: fix unitialized boolean 'want'
  firmware: change kernel read fail to dev_dbg()
  KEYS: Use the symbol value for list size, updated by scripts/insert-sys-cert
  KEYS: Reserve an extra certificate symbol for inserting without recompiling
  modsign: hide openssl output in silent builds
  tpm_tis: fix build warning with tpm_tis_resume
  ima: require signed IMA policy
  ima: measure and appraise the IMA policy itself
  ima: load policy using path
  ...
2016-03-17 11:33:45 -07:00
Linus Torvalds
70477371dc Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "Here is the crypto update for 4.6:

  API:
   - Convert remaining crypto_hash users to shash or ahash, also convert
     blkcipher/ablkcipher users to skcipher.
   - Remove crypto_hash interface.
   - Remove crypto_pcomp interface.
   - Add crypto engine for async cipher drivers.
   - Add akcipher documentation.
   - Add skcipher documentation.

  Algorithms:
   - Rename crypto/crc32 to avoid name clash with lib/crc32.
   - Fix bug in keywrap where we zero the wrong pointer.

  Drivers:
   - Support T5/M5, T7/M7 SPARC CPUs in n2 hwrng driver.
   - Add PIC32 hwrng driver.
   - Support BCM6368 in bcm63xx hwrng driver.
   - Pack structs for 32-bit compat users in qat.
   - Use crypto engine in omap-aes.
   - Add support for sama5d2x SoCs in atmel-sha.
   - Make atmel-sha available again.
   - Make sahara hashing available again.
   - Make ccp hashing available again.
   - Make sha1-mb available again.
   - Add support for multiple devices in ccp.
   - Improve DMA performance in caam.
   - Add hashing support to rockchip"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (116 commits)
  crypto: qat - remove redundant arbiter configuration
  crypto: ux500 - fix checks of error code returned by devm_ioremap_resource()
  crypto: atmel - fix checks of error code returned by devm_ioremap_resource()
  crypto: qat - Change the definition of icp_qat_uof_regtype
  hwrng: exynos - use __maybe_unused to hide pm functions
  crypto: ccp - Add abstraction for device-specific calls
  crypto: ccp - CCP versioning support
  crypto: ccp - Support for multiple CCPs
  crypto: ccp - Remove check for x86 family and model
  crypto: ccp - memset request context to zero during import
  lib/mpi: use "static inline" instead of "extern inline"
  lib/mpi: avoid assembler warning
  hwrng: bcm63xx - fix non device tree compatibility
  crypto: testmgr - allow rfc3686 aes-ctr variants in fips mode.
  crypto: qat - The AE id should be less than the maximal AE number
  lib/mpi: Endianness fix
  crypto: rockchip - add hash support for crypto engine in rk3288
  crypto: xts - fix compile errors
  crypto: doc - add skcipher API documentation
  crypto: doc - update AEAD AD handling
  ...
2016-03-17 11:22:54 -07:00
James Morris
88a1b564a2 Merge tag 'keys-next-20160303' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs into next 2016-03-04 11:39:53 +11:00
Paul Gortmaker
a1f2bdf338 security/keys: make big_key.c explicitly non-modular
The Kconfig currently controlling compilation of this code is:

config BIG_KEYS
        bool "Large payload keys"

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We also delete the MODULE_LICENSE tag since all that information
is already contained at the top of the file in the comments.

Cc: James Morris <james.l.morris@oracle.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: keyrings@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2016-02-18 15:15:59 +00:00
Jarkko Sakkinen
f3c82ade7c tpm: fix checks for policy digest existence in tpm2_seal_trusted()
In my original patch sealing with policy was done with dynamically
allocated buffer that I changed later into an array so the checks in
tpm2-cmd.c became invalid. This patch fixes the issue.

Fixes: 5beb0c435b ("keys, trusted: seal with a TPM2 authorization policy")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
2016-02-10 04:10:55 +02:00
David Howells
5d2787cf0b KEYS: Add an alloc flag to convey the builtinness of a key
Add KEY_ALLOC_BUILT_IN to convey that a key should have KEY_FLAG_BUILTIN
set rather than setting it after the fact.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2016-02-09 16:40:46 +00:00
David Howells
eee045021f KEYS: Only apply KEY_FLAG_KEEP to a key if a parent keyring has it set
KEY_FLAG_KEEP should only be applied to a key if the keyring it is being
linked into has KEY_FLAG_KEEP set.

To this end, partially revert the following patch:

	commit 1d6d167c2e
	Author: Mimi Zohar <zohar@linux.vnet.ibm.com>
	Date:   Thu Jan 7 07:46:36 2016 -0500
	KEYS: refcount bug fix

to undo the change that made it unconditional (Mimi got it right the first
time).

Without undoing this change, it becomes impossible to delete, revoke or
invalidate keys added to keyrings through __key_instantiate_and_link()
where the keyring has itself been linked to.  To test this, run the
following command sequence:

    keyctl newring foo @s
    keyctl add user a a %:foo
    keyctl unlink %user:a %:foo
    keyctl clear %:foo

With the commit mentioned above the third and fourth commands fail with
EPERM when they should succeed.

Reported-by: Stephen Gallager <sgallagh@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by:  Mimi Zohar <zohar@linux.vnet.ibm.com>
cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
cc: keyrings@vger.kernel.org
cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-01-28 10:48:40 +11:00
Herbert Xu
c3917fd9df KEYS: Use skcipher
This patch replaces uses of blkcipher with skcipher.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-01-27 20:36:03 +08:00
Yevgeny Pats
23567fd052 KEYS: Fix keyring ref leak in join_session_keyring()
This fixes CVE-2016-0728.

If a thread is asked to join as a session keyring the keyring that's already
set as its session, we leak a keyring reference.

This can be tested with the following program:

	#include <stddef.h>
	#include <stdio.h>
	#include <sys/types.h>
	#include <keyutils.h>

	int main(int argc, const char *argv[])
	{
		int i = 0;
		key_serial_t serial;

		serial = keyctl(KEYCTL_JOIN_SESSION_KEYRING,
				"leaked-keyring");
		if (serial < 0) {
			perror("keyctl");
			return -1;
		}

		if (keyctl(KEYCTL_SETPERM, serial,
			   KEY_POS_ALL | KEY_USR_ALL) < 0) {
			perror("keyctl");
			return -1;
		}

		for (i = 0; i < 100; i++) {
			serial = keyctl(KEYCTL_JOIN_SESSION_KEYRING,
					"leaked-keyring");
			if (serial < 0) {
				perror("keyctl");
				return -1;
			}
		}

		return 0;
	}

If, after the program has run, there something like the following line in
/proc/keys:

3f3d898f I--Q---   100 perm 3f3f0000     0     0 keyring   leaked-keyring: empty

with a usage count of 100 * the number of times the program has been run,
then the kernel is malfunctioning.  If leaked-keyring has zero usages or
has been garbage collected, then the problem is fixed.

Reported-by: Yevgeny Pats <yevgeny@perception-point.io>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-01-20 10:50:48 +11:00
Linus Torvalds
5807fcaa9b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:

 - EVM gains support for loading an x509 cert from the kernel
   (EVM_LOAD_X509), into the EVM trusted kernel keyring.

 - Smack implements 'file receive' process-based permission checking for
   sockets, rather than just depending on inode checks.

 - Misc enhancments for TPM & TPM2.

 - Cleanups and bugfixes for SELinux, Keys, and IMA.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (41 commits)
  selinux: Inode label revalidation performance fix
  KEYS: refcount bug fix
  ima: ima_write_policy() limit locking
  IMA: policy can be updated zero times
  selinux: rate-limit netlink message warnings in selinux_nlmsg_perm()
  selinux: export validatetrans decisions
  gfs2: Invalid security labels of inodes when they go invalid
  selinux: Revalidate invalid inode security labels
  security: Add hook to invalidate inode security labels
  selinux: Add accessor functions for inode->i_security
  security: Make inode argument of inode_getsecid non-const
  security: Make inode argument of inode_getsecurity non-const
  selinux: Remove unused variable in selinux_inode_init_security
  keys, trusted: seal with a TPM2 authorization policy
  keys, trusted: select hash algorithm for TPM2 chips
  keys, trusted: fix: *do not* allow duplicate key options
  tpm_ibmvtpm: properly handle interrupted packet receptions
  tpm_tis: Tighten IRQ auto-probing
  tpm_tis: Refactor the interrupt setup
  tpm_tis: Get rid of the duplicate IRQ probing code
  ...
2016-01-17 19:13:15 -08:00
James Morris
607259e17b Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into ra-next 2016-01-10 21:52:17 +11:00
Mimi Zohar
1d6d167c2e KEYS: refcount bug fix
This patch fixes the key_ref leak, removes the unnecessary KEY_FLAG_KEEP
test before setting the flag, and cleans up the if/then brackets style
introduced in commit:
d3600bc KEYS: prevent keys from being removed from specified keyrings

Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
2016-01-07 12:56:42 -05:00
James Morris
3cb92fe481 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into next 2015-12-26 16:06:53 +11:00
Jarkko Sakkinen
5beb0c435b keys, trusted: seal with a TPM2 authorization policy
TPM2 supports authorization policies, which are essentially
combinational logic statements repsenting the conditions where the data
can be unsealed based on the TPM state. This patch enables to use
authorization policies to seal trusted keys.

Two following new options have been added for trusted keys:

* 'policydigest=': provide an auth policy digest for sealing.
* 'policyhandle=': provide a policy session handle for unsealing.

If 'hash=' option is supplied after 'policydigest=' option, this
will result an error because the state of the option would become
mixed.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
2015-12-20 15:27:13 +02:00
Jarkko Sakkinen
5ca4c20cfd keys, trusted: select hash algorithm for TPM2 chips
Added 'hash=' option for selecting the hash algorithm for add_key()
syscall and documentation for it.

Added entry for sm3-256 to the following tables in order to support
TPM_ALG_SM3_256:

* hash_algo_name
* hash_digest_size

Includes support for the following hash algorithms:

* sha1
* sha256
* sha384
* sha512
* sm3-256

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
2015-12-20 15:27:12 +02:00
Jarkko Sakkinen
5208cc8342 keys, trusted: fix: *do not* allow duplicate key options
The trusted keys option parsing allows specifying the same option
multiple times. The last option value specified is used.

This is problematic because:

* No gain.
* This makes complicated to specify options that are dependent on other
  options.

This patch changes the behavior in a way that option can be specified
only once.

Reported-by: James Morris James Morris <jmorris@namei.org>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
2015-12-20 15:27:12 +02:00
David Howells
b4a1b4f504 KEYS: Fix race between read and revoke
This fixes CVE-2015-7550.

There's a race between keyctl_read() and keyctl_revoke().  If the revoke
happens between keyctl_read() checking the validity of a key and the key's
semaphore being taken, then the key type read method will see a revoked key.

This causes a problem for the user-defined key type because it assumes in
its read method that there will always be a payload in a non-revoked key
and doesn't check for a NULL pointer.

Fix this by making keyctl_read() check the validity of a key after taking
semaphore instead of before.

I think the bug was introduced with the original keyrings code.

This was discovered by a multithreaded test program generated by syzkaller
(http://github.com/google/syzkaller).  Here's a cleaned up version:

	#include <sys/types.h>
	#include <keyutils.h>
	#include <pthread.h>
	void *thr0(void *arg)
	{
		key_serial_t key = (unsigned long)arg;
		keyctl_revoke(key);
		return 0;
	}
	void *thr1(void *arg)
	{
		key_serial_t key = (unsigned long)arg;
		char buffer[16];
		keyctl_read(key, buffer, 16);
		return 0;
	}
	int main()
	{
		key_serial_t key = add_key("user", "%", "foo", 3, KEY_SPEC_USER_KEYRING);
		pthread_t th[5];
		pthread_create(&th[0], 0, thr0, (void *)(unsigned long)key);
		pthread_create(&th[1], 0, thr1, (void *)(unsigned long)key);
		pthread_create(&th[2], 0, thr0, (void *)(unsigned long)key);
		pthread_create(&th[3], 0, thr1, (void *)(unsigned long)key);
		pthread_join(th[0], 0);
		pthread_join(th[1], 0);
		pthread_join(th[2], 0);
		pthread_join(th[3], 0);
		return 0;
	}

Build as:

	cc -o keyctl-race keyctl-race.c -lkeyutils -lpthread

Run as:

	while keyctl-race; do :; done

as it may need several iterations to crash the kernel.  The crash can be
summarised as:

	BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
	IP: [<ffffffff81279b08>] user_read+0x56/0xa3
	...
	Call Trace:
	 [<ffffffff81276aa9>] keyctl_read_key+0xb6/0xd7
	 [<ffffffff81277815>] SyS_keyctl+0x83/0xe0
	 [<ffffffff815dbb97>] entry_SYSCALL_64_fastpath+0x12/0x6f

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-12-19 12:34:43 +11:00
Mimi Zohar
d3600bcf9d KEYS: prevent keys from being removed from specified keyrings
Userspace should not be allowed to remove keys from certain keyrings
(eg. blacklist), though the keys themselves can expire.

This patch defines a new key flag named KEY_FLAG_KEEP to prevent
userspace from being able to unlink, revoke, invalidate or timed
out a key on a keyring.  When this flag is set on the keyring, all
keys subsequently added are flagged.

In addition, when this flag is set, the keyring itself can not be
cleared.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: David Howells <dhowells@redhat.com>
2015-12-15 10:01:43 -05:00
David Howells
096fe9eaea KEYS: Fix handling of stored error in a negatively instantiated user key
If a user key gets negatively instantiated, an error code is cached in the
payload area.  A negatively instantiated key may be then be positively
instantiated by updating it with valid data.  However, the ->update key
type method must be aware that the error code may be there.

The following may be used to trigger the bug in the user key type:

    keyctl request2 user user "" @u
    keyctl add user user "a" @u

which manifests itself as:

	BUG: unable to handle kernel paging request at 00000000ffffff8a
	IP: [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280 kernel/rcu/tree.c:3046
	PGD 7cc30067 PUD 0
	Oops: 0002 [#1] SMP
	Modules linked in:
	CPU: 3 PID: 2644 Comm: a.out Not tainted 4.3.0+ #49
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
	task: ffff88003ddea700 ti: ffff88003dd88000 task.ti: ffff88003dd88000
	RIP: 0010:[<ffffffff810a376f>]  [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280
	 [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280 kernel/rcu/tree.c:3046
	RSP: 0018:ffff88003dd8bdb0  EFLAGS: 00010246
	RAX: 00000000ffffff82 RBX: 0000000000000000 RCX: 0000000000000001
	RDX: ffffffff81e3fe40 RSI: 0000000000000000 RDI: 00000000ffffff82
	RBP: ffff88003dd8bde0 R08: ffff88007d2d2da0 R09: 0000000000000000
	R10: 0000000000000000 R11: ffff88003e8073c0 R12: 00000000ffffff82
	R13: ffff88003dd8be68 R14: ffff88007d027600 R15: ffff88003ddea700
	FS:  0000000000b92880(0063) GS:ffff88007fd00000(0000) knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
	CR2: 00000000ffffff8a CR3: 000000007cc5f000 CR4: 00000000000006e0
	Stack:
	 ffff88003dd8bdf0 ffffffff81160a8a 0000000000000000 00000000ffffff82
	 ffff88003dd8be68 ffff88007d027600 ffff88003dd8bdf0 ffffffff810a39e5
	 ffff88003dd8be20 ffffffff812a31ab ffff88007d027600 ffff88007d027620
	Call Trace:
	 [<ffffffff810a39e5>] kfree_call_rcu+0x15/0x20 kernel/rcu/tree.c:3136
	 [<ffffffff812a31ab>] user_update+0x8b/0xb0 security/keys/user_defined.c:129
	 [<     inline     >] __key_update security/keys/key.c:730
	 [<ffffffff8129e5c1>] key_create_or_update+0x291/0x440 security/keys/key.c:908
	 [<     inline     >] SYSC_add_key security/keys/keyctl.c:125
	 [<ffffffff8129fc21>] SyS_add_key+0x101/0x1e0 security/keys/keyctl.c:60
	 [<ffffffff8185f617>] entry_SYSCALL_64_fastpath+0x12/0x6a arch/x86/entry/entry_64.S:185

Note the error code (-ENOKEY) in EDX.

A similar bug can be tripped by:

    keyctl request2 trusted user "" @u
    keyctl add trusted user "a" @u

This should also affect encrypted keys - but that has to be correctly
parameterised or it will fail with EINVAL before getting to the bit that
will crashes.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-11-25 14:19:47 +11:00
Linus Torvalds
1873499e13 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem update from James Morris:
 "This is mostly maintenance updates across the subsystem, with a
  notable update for TPM 2.0, and addition of Jarkko Sakkinen as a
  maintainer of that"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (40 commits)
  apparmor: clarify CRYPTO dependency
  selinux: Use a kmem_cache for allocation struct file_security_struct
  selinux: ioctl_has_perm should be static
  selinux: use sprintf return value
  selinux: use kstrdup() in security_get_bools()
  selinux: use kmemdup in security_sid_to_context_core()
  selinux: remove pointless cast in selinux_inode_setsecurity()
  selinux: introduce security_context_str_to_sid
  selinux: do not check open perm on ftruncate call
  selinux: change CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default
  KEYS: Merge the type-specific data with the payload data
  KEYS: Provide a script to extract a module signature
  KEYS: Provide a script to extract the sys cert list from a vmlinux file
  keys: Be more consistent in selection of union members used
  certs: add .gitignore to stop git nagging about x509_certificate_list
  KEYS: use kvfree() in add_key
  Smack: limited capability for changing process label
  TPM: remove unnecessary little endian conversion
  vTPM: support little endian guests
  char: Drop owner assignment from i2c_driver
  ...
2015-11-05 15:32:38 -08:00
David Howells
146aa8b145 KEYS: Merge the type-specific data with the payload data
Merge the type-specific data with the payload data into one four-word chunk
as it seems pointless to keep them separate.

Use user_key_payload() for accessing the payloads of overloaded
user-defined keys.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-cifs@vger.kernel.org
cc: ecryptfs@vger.kernel.org
cc: linux-ext4@vger.kernel.org
cc: linux-f2fs-devel@lists.sourceforge.net
cc: linux-nfs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: linux-ima-devel@lists.sourceforge.net
2015-10-21 15:18:36 +01:00
Insu Yun
27720e75a7 keys: Be more consistent in selection of union members used
key->description and key->index_key.description are same because
they are unioned. But, for readability, using same name for
duplication and validation seems better.

Signed-off-by: Insu Yun <wuninsu@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-10-21 15:18:35 +01:00
Geliang Tang
d0e0eba043 KEYS: use kvfree() in add_key
There is no need to make a flag to tell that this memory is allocated by
kmalloc or vmalloc. Just use kvfree to free the memory.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-10-21 15:18:35 +01:00
David Howells
911b79cde9 KEYS: Don't permit request_key() to construct a new keyring
If request_key() is used to find a keyring, only do the search part - don't
do the construction part if the keyring was not found by the search.  We
don't really want keyrings in the negative instantiated state since the
rejected/negative instantiation error value in the payload is unioned with
keyring metadata.

Now the kernel gives an error:

	request_key("keyring", "#selinux,bdekeyring", "keyring", KEY_SPEC_USER_SESSION_KEYRING) = -1 EPERM (Operation not permitted)

Signed-off-by: David Howells <dhowells@redhat.com>
2015-10-19 11:24:51 +01:00
Jarkko Sakkinen
0fe5480303 keys, trusted: seal/unseal with TPM 2.0 chips
Call tpm_seal_trusted() and tpm_unseal_trusted() for TPM 2.0 chips.
We require explicit 'keyhandle=' option because there's no a fixed
storage root key inside TPM2 chips.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Andreas Fuchs <andreas.fuchs@sit.fraunhofer.de>
Tested-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (on TPM 1.2)
Tested-by: Chris J Arges <chris.j.arges@canonical.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Tested-by: Kevin Strasser <kevin.strasser@intel.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2015-10-19 01:01:22 +02:00
Jarkko Sakkinen
fe351e8d4e keys, trusted: move struct trusted_key_options to trusted-type.h
Moved struct trusted_key_options to trustes-type.h so that the fields
can be accessed from drivers/char/tpm.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2015-10-19 01:01:21 +02:00
David Howells
f05819df10 KEYS: Fix crash when attempt to garbage collect an uninstantiated keyring
The following sequence of commands:

    i=`keyctl add user a a @s`
    keyctl request2 keyring foo bar @t
    keyctl unlink $i @s

tries to invoke an upcall to instantiate a keyring if one doesn't already
exist by that name within the user's keyring set.  However, if the upcall
fails, the code sets keyring->type_data.reject_error to -ENOKEY or some
other error code.  When the key is garbage collected, the key destroy
function is called unconditionally and keyring_destroy() uses list_empty()
on keyring->type_data.link - which is in a union with reject_error.
Subsequently, the kernel tries to unlink the keyring from the keyring names
list - which oopses like this:

	BUG: unable to handle kernel paging request at 00000000ffffff8a
	IP: [<ffffffff8126e051>] keyring_destroy+0x3d/0x88
	...
	Workqueue: events key_garbage_collector
	...
	RIP: 0010:[<ffffffff8126e051>] keyring_destroy+0x3d/0x88
	RSP: 0018:ffff88003e2f3d30  EFLAGS: 00010203
	RAX: 00000000ffffff82 RBX: ffff88003bf1a900 RCX: 0000000000000000
	RDX: 0000000000000000 RSI: 000000003bfc6901 RDI: ffffffff81a73a40
	RBP: ffff88003e2f3d38 R08: 0000000000000152 R09: 0000000000000000
	R10: ffff88003e2f3c18 R11: 000000000000865b R12: ffff88003bf1a900
	R13: 0000000000000000 R14: ffff88003bf1a908 R15: ffff88003e2f4000
	...
	CR2: 00000000ffffff8a CR3: 000000003e3ec000 CR4: 00000000000006f0
	...
	Call Trace:
	 [<ffffffff8126c756>] key_gc_unused_keys.constprop.1+0x5d/0x10f
	 [<ffffffff8126ca71>] key_garbage_collector+0x1fa/0x351
	 [<ffffffff8105ec9b>] process_one_work+0x28e/0x547
	 [<ffffffff8105fd17>] worker_thread+0x26e/0x361
	 [<ffffffff8105faa9>] ? rescuer_thread+0x2a8/0x2a8
	 [<ffffffff810648ad>] kthread+0xf3/0xfb
	 [<ffffffff810647ba>] ? kthread_create_on_node+0x1c2/0x1c2
	 [<ffffffff815f2ccf>] ret_from_fork+0x3f/0x70
	 [<ffffffff810647ba>] ? kthread_create_on_node+0x1c2/0x1c2

Note the value in RAX.  This is a 32-bit representation of -ENOKEY.

The solution is to only call ->destroy() if the key was successfully
instantiated.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
2015-10-15 17:21:37 +01:00
David Howells
94c4554ba0 KEYS: Fix race between key destruction and finding a keyring by name
There appears to be a race between:

 (1) key_gc_unused_keys() which frees key->security and then calls
     keyring_destroy() to unlink the name from the name list

 (2) find_keyring_by_name() which calls key_permission(), thus accessing
     key->security, on a key before checking to see whether the key usage is 0
     (ie. the key is dead and might be cleaned up).

Fix this by calling ->destroy() before cleaning up the core key data -
including key->security.

Reported-by: Petr Matousek <pmatouse@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-09-25 16:30:08 +01:00
Andy Lutomirski
58319057b7 capabilities: ambient capabilities
Credit where credit is due: this idea comes from Christoph Lameter with
a lot of valuable input from Serge Hallyn.  This patch is heavily based
on Christoph's patch.

===== The status quo =====

On Linux, there are a number of capabilities defined by the kernel.  To
perform various privileged tasks, processes can wield capabilities that
they hold.

Each task has four capability masks: effective (pE), permitted (pP),
inheritable (pI), and a bounding set (X).  When the kernel checks for a
capability, it checks pE.  The other capability masks serve to modify
what capabilities can be in pE.

Any task can remove capabilities from pE, pP, or pI at any time.  If a
task has a capability in pP, it can add that capability to pE and/or pI.
If a task has CAP_SETPCAP, then it can add any capability to pI, and it
can remove capabilities from X.

Tasks are not the only things that can have capabilities; files can also
have capabilities.  A file can have no capabilty information at all [1].
If a file has capability information, then it has a permitted mask (fP)
and an inheritable mask (fI) as well as a single effective bit (fE) [2].
File capabilities modify the capabilities of tasks that execve(2) them.

A task that successfully calls execve has its capabilities modified for
the file ultimately being excecuted (i.e.  the binary itself if that
binary is ELF or for the interpreter if the binary is a script.) [3] In
the capability evolution rules, for each mask Z, pZ represents the old
value and pZ' represents the new value.  The rules are:

  pP' = (X & fP) | (pI & fI)
  pI' = pI
  pE' = (fE ? pP' : 0)
  X is unchanged

For setuid binaries, fP, fI, and fE are modified by a moderately
complicated set of rules that emulate POSIX behavior.  Similarly, if
euid == 0 or ruid == 0, then fP, fI, and fE are modified differently
(primary, fP and fI usually end up being the full set).  For nonroot
users executing binaries with neither setuid nor file caps, fI and fP
are empty and fE is false.

As an extra complication, if you execute a process as nonroot and fE is
set, then the "secure exec" rules are in effect: AT_SECURE gets set,
LD_PRELOAD doesn't work, etc.

This is rather messy.  We've learned that making any changes is
dangerous, though: if a new kernel version allows an unprivileged
program to change its security state in a way that persists cross
execution of a setuid program or a program with file caps, this
persistent state is surprisingly likely to allow setuid or file-capped
programs to be exploited for privilege escalation.

===== The problem =====

Capability inheritance is basically useless.

If you aren't root and you execute an ordinary binary, fI is zero, so
your capabilities have no effect whatsoever on pP'.  This means that you
can't usefully execute a helper process or a shell command with elevated
capabilities if you aren't root.

On current kernels, you can sort of work around this by setting fI to
the full set for most or all non-setuid executable files.  This causes
pP' = pI for nonroot, and inheritance works.  No one does this because
it's a PITA and it isn't even supported on most filesystems.

If you try this, you'll discover that every nonroot program ends up with
secure exec rules, breaking many things.

This is a problem that has bitten many people who have tried to use
capabilities for anything useful.

===== The proposed change =====

This patch adds a fifth capability mask called the ambient mask (pA).
pA does what most people expect pI to do.

pA obeys the invariant that no bit can ever be set in pA if it is not
set in both pP and pI.  Dropping a bit from pP or pI drops that bit from
pA.  This ensures that existing programs that try to drop capabilities
still do so, with a complication.  Because capability inheritance is so
broken, setting KEEPCAPS, using setresuid to switch to nonroot uids, and
then calling execve effectively drops capabilities.  Therefore,
setresuid from root to nonroot conditionally clears pA unless
SECBIT_NO_SETUID_FIXUP is set.  Processes that don't like this can
re-add bits to pA afterwards.

The capability evolution rules are changed:

  pA' = (file caps or setuid or setgid ? 0 : pA)
  pP' = (X & fP) | (pI & fI) | pA'
  pI' = pI
  pE' = (fE ? pP' : pA')
  X is unchanged

If you are nonroot but you have a capability, you can add it to pA.  If
you do so, your children get that capability in pA, pP, and pE.  For
example, you can set pA = CAP_NET_BIND_SERVICE, and your children can
automatically bind low-numbered ports.  Hallelujah!

Unprivileged users can create user namespaces, map themselves to a
nonzero uid, and create both privileged (relative to their namespace)
and unprivileged process trees.  This is currently more or less
impossible.  Hallelujah!

You cannot use pA to try to subvert a setuid, setgid, or file-capped
program: if you execute any such program, pA gets cleared and the
resulting evolution rules are unchanged by this patch.

Users with nonzero pA are unlikely to unintentionally leak that
capability.  If they run programs that try to drop privileges, dropping
privileges will still work.

It's worth noting that the degree of paranoia in this patch could
possibly be reduced without causing serious problems.  Specifically, if
we allowed pA to persist across executing non-pA-aware setuid binaries
and across setresuid, then, naively, the only capabilities that could
leak as a result would be the capabilities in pA, and any attacker
*already* has those capabilities.  This would make me nervous, though --
setuid binaries that tried to privilege-separate might fail to do so,
and putting CAP_DAC_READ_SEARCH or CAP_DAC_OVERRIDE into pA could have
unexpected side effects.  (Whether these unexpected side effects would
be exploitable is an open question.) I've therefore taken the more
paranoid route.  We can revisit this later.

An alternative would be to require PR_SET_NO_NEW_PRIVS before setting
ambient capabilities.  I think that this would be annoying and would
make granting otherwise unprivileged users minor ambient capabilities
(CAP_NET_BIND_SERVICE or CAP_NET_RAW for example) much less useful than
it is with this patch.

===== Footnotes =====

[1] Files that are missing the "security.capability" xattr or that have
unrecognized values for that xattr end up with has_cap set to false.
The code that does that appears to be complicated for no good reason.

[2] The libcap capability mask parsers and formatters are dangerously
misleading and the documentation is flat-out wrong.  fE is *not* a mask;
it's a single bit.  This has probably confused every single person who
has tried to use file capabilities.

[3] Linux very confusingly processes both the script and the interpreter
if applicable, for reasons that elude me.  The results from thinking
about a script's file capabilities and/or setuid bits are mostly
discarded.

Preliminary userspace code is here, but it needs updating:
https://git.kernel.org/cgit/linux/kernel/git/luto/util-linux-playground.git/commit/?h=cap_ambient&id=7f5afbd175d2

Here is a test program that can be used to verify the functionality
(from Christoph):

/*
 * Test program for the ambient capabilities. This program spawns a shell
 * that allows running processes with a defined set of capabilities.
 *
 * (C) 2015 Christoph Lameter <cl@linux.com>
 * Released under: GPL v3 or later.
 *
 *
 * Compile using:
 *
 *	gcc -o ambient_test ambient_test.o -lcap-ng
 *
 * This program must have the following capabilities to run properly:
 * Permissions for CAP_NET_RAW, CAP_NET_ADMIN, CAP_SYS_NICE
 *
 * A command to equip the binary with the right caps is:
 *
 *	setcap cap_net_raw,cap_net_admin,cap_sys_nice+p ambient_test
 *
 *
 * To get a shell with additional caps that can be inherited by other processes:
 *
 *	./ambient_test /bin/bash
 *
 *
 * Verifying that it works:
 *
 * From the bash spawed by ambient_test run
 *
 *	cat /proc/$$/status
 *
 * and have a look at the capabilities.
 */

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <cap-ng.h>
#include <sys/prctl.h>
#include <linux/capability.h>

/*
 * Definitions from the kernel header files. These are going to be removed
 * when the /usr/include files have these defined.
 */
#define PR_CAP_AMBIENT 47
#define PR_CAP_AMBIENT_IS_SET 1
#define PR_CAP_AMBIENT_RAISE 2
#define PR_CAP_AMBIENT_LOWER 3
#define PR_CAP_AMBIENT_CLEAR_ALL 4

static void set_ambient_cap(int cap)
{
	int rc;

	capng_get_caps_process();
	rc = capng_update(CAPNG_ADD, CAPNG_INHERITABLE, cap);
	if (rc) {
		printf("Cannot add inheritable cap\n");
		exit(2);
	}
	capng_apply(CAPNG_SELECT_CAPS);

	/* Note the two 0s at the end. Kernel checks for these */
	if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_RAISE, cap, 0, 0)) {
		perror("Cannot set cap");
		exit(1);
	}
}

int main(int argc, char **argv)
{
	int rc;

	set_ambient_cap(CAP_NET_RAW);
	set_ambient_cap(CAP_NET_ADMIN);
	set_ambient_cap(CAP_SYS_NICE);

	printf("Ambient_test forking shell\n");
	if (execv(argv[1], argv + 1))
		perror("Cannot exec");

	return 0;
}

Signed-off-by: Christoph Lameter <cl@linux.com> # Original author
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Aaron Jones <aaronmdjones@gmail.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Andrew G. Morgan <morgan@kernel.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Austin S Hemmelgarn <ahferroin7@gmail.com>
Cc: Markku Savela <msa@moth.iki.fi>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: James Morris <james.l.morris@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Colin Ian King
ca4da5dd1f KEYS: ensure we free the assoc array edit if edit is valid
__key_link_end is not freeing the associated array edit structure
and this leads to a 512 byte memory leak each time an identical
existing key is added with add_key().

The reason the add_key() system call returns okay is that
key_create_or_update() calls __key_link_begin() before checking to see
whether it can update a key directly rather than adding/replacing - which
it turns out it can.  Thus __key_link() is not called through
__key_instantiate_and_link() and __key_link_end() must cancel the edit.

CVE-2015-1333

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-07-28 13:08:23 +10:00
Al Viro
b353a1f7bb switch keyctl_instantiate_key_common() to iov_iter
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:27:12 -04:00
David Jeffery
d0709f1e66 Don't leak a key reference if request_key() tries to use a revoked keyring
If a request_key() call to allocate and fill out a key attempts to insert the
key structure into a revoked keyring, the key will leak, using memory and part
of the user's key quota until the system reboots. This is from a failure of
construct_alloc_key() to decrement the key's reference count after the attempt
to insert into the requested keyring is rejected.

key_put() needs to be called in the link_prealloc_failed callpath to ensure
the unused key is released.

Signed-off-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-02-16 13:45:16 +11:00
David Howells
dabd39cc2f KEYS: Make /proc/keys unconditional if CONFIG_KEYS=y
Now that /proc/keys is used by libkeyutils to look up a key by type and
description, we should make it unconditional and remove
CONFIG_DEBUG_PROC_KEYS.

Reported-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Jiri Kosina <jkosina@suse.cz>
2015-01-22 22:34:32 +00:00
Sasha Levin
a3a8784454 KEYS: close race between key lookup and freeing
When a key is being garbage collected, it's key->user would get put before
the ->destroy() callback is called, where the key is removed from it's
respective tracking structures.

This leaves a key hanging in a semi-invalid state which leaves a window open
for a different task to try an access key->user. An example is
find_keyring_by_name() which would dereference key->user for a key that is
in the process of being garbage collected (where key->user was freed but
->destroy() wasn't called yet - so it's still present in the linked list).

This would cause either a panic, or corrupt memory.

Fixes CVE-2014-9529.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-01-05 15:58:01 +00:00
Dan Carpenter
5057975ae3 KEYS: remove a bogus NULL check
We already checked if "desc" was NULL at the beginning of the function
and we've dereferenced it so this causes a static checker warning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2014-12-16 18:05:20 +11:00
James Morris
d0bffab043 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into for-linus 2014-12-16 12:49:10 +11:00
Takashi Iwai
b26bdde5bb KEYS: Fix stale key registration at error path
When loading encrypted-keys module, if the last check of
aes_get_sizes() in init_encrypted() fails, the driver just returns an
error without unregistering its key type.  This results in the stale
entry in the list.  In addition to memory leaks, this leads to a kernel
crash when registering a new key type later.

This patch fixes the problem by swapping the calls of aes_get_sizes()
and register_key_type(), and releasing resources properly at the error
paths.

Bugzilla: https://bugzilla.opensuse.org/show_bug.cgi?id=908163
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-12-06 21:50:36 -05:00
David Howells
0b0a84154e KEYS: request_key() should reget expired keys rather than give EKEYEXPIRED
Since the keyring facility can be viewed as a cache (at least in some
applications), the local expiration time on the key should probably be viewed
as a 'needs updating after this time' property rather than an absolute 'anyone
now wanting to use this object is out of luck' property.

Since request_key() is the main interface for the usage of keys, this should
update or replace an expired key rather than issuing EKEYEXPIRED if the local
expiration has been reached (ie. it should refresh the cache).

For absolute conditions where refreshing the cache probably doesn't help, the
key can be negatively instantiated using KEYCTL_REJECT_KEY with EKEYEXPIRED
given as the error to issue.  This will still cause request_key() to return
EKEYEXPIRED as that was explicitly set.

In the future, if the key type has an update op available, we might want to
upcall with the expired key and allow the upcall to update it.  We would pass
a different operation name (the first column in /etc/request-key.conf) to the
request-key program.

request_key() returning EKEYEXPIRED is causing an NFS problem which Chuck
Lever describes thusly:

	After about 10 minutes, my NFSv4 functional tests fail because the
	ownership of the test files goes to "-2". Looking at /proc/keys
	shows that the id_resolv keys that map to my test user ID have
	expired. The ownership problem persists until the expired keys are
	purged from the keyring, and fresh keys are obtained.

	I bisected the problem to 3.13 commit b2a4df200d ("KEYS: Expand
	the capacity of a keyring"). This commit inadvertantly changes the
	API contract of the internal function keyring_search_aux().

	The root cause appears to be that b2a4df200d made "no state check"
	the default behavior. "No state check" means the keyring search
	iterator function skips checking the key's expiry timeout, and
	returns expired keys.  request_key_and_link() depends on getting
	an -EAGAIN result code to know when to perform an upcall to refresh
	an expired key.

This patch can be tested directly by:

	keyctl request2 user debug:fred a @s
	keyctl timeout %user:debug:fred 3
	sleep 4
	keyctl request2 user debug:fred a @s

Without the patch, the last command gives error EKEYEXPIRED, but with the
command it gives a new key.

Reported-by: Carl Hetherington <cth@carlh.net>
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2014-12-01 22:52:53 +00:00
David Howells
054f6180d8 KEYS: Simplify KEYRING_SEARCH_{NO,DO}_STATE_CHECK flags
Simplify KEYRING_SEARCH_{NO,DO}_STATE_CHECK flags to be two variations of the
same flag.  They are effectively mutually exclusive and one or the other
should be provided, but not both.

Keyring cycle detection and key possession determination are the only things
that set NO_STATE_CHECK, except that neither flag really does anything there
because neither purpose makes use of the keyring_search_iterator() function,
but rather provides their own.

For cycle detection we definitely want to check inside of expired keyrings,
just so that we don't create a cycle we can't get rid of.  Revoked keyrings
are cleared at revocation time and can't then be reused, so shouldn't be a
problem either way.

For possession determination, we *might* want to validate each keyring before
searching it: do you possess a key that's hidden behind an expired or just
plain inaccessible keyring?  Currently, the answer is yes.  Note that you
cannot, however, possess a key behind a revoked keyring because they are
cleared on revocation.

keyring_search() sets DO_STATE_CHECK, which is correct.

request_key_and_link() currently doesn't specify whether to check the key
state or not - but it should set DO_STATE_CHECK.

key_get_instantiation_authkey() also currently doesn't specify whether to
check the key state or not - but it probably should also set DO_STATE_CHECK.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2014-12-01 22:52:50 +00:00
David Howells
aa9d443789 KEYS: Fix the size of the key description passed to/from userspace
When a key description argument is imported into the kernel from userspace, as
happens in add_key(), request_key(), KEYCTL_JOIN_SESSION_KEYRING,
KEYCTL_SEARCH, the description is copied into a buffer up to PAGE_SIZE in size.
PAGE_SIZE, however, is a variable quantity, depending on the arch.  Fix this at
4096 instead (ie. 4095 plus a NUL termination) and define a constant
(KEY_MAX_DESC_SIZE) to this end.

When reading the description back with KEYCTL_DESCRIBE, a PAGE_SIZE internal
buffer is allocated into which the information and description will be
rendered.  This means that the description will get truncated if an extremely
long description it has to be crammed into the buffer with the stringified
information.  There is no particular need to copy the description into the
buffer, so just copy it directly to userspace in a separate operation.

Reported-by: Christian Kastner <debian@kvr.at>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Christian Kastner <debian@kvr.at>
2014-12-01 22:52:45 +00:00
James Morris
b10778a00d Merge commit 'v3.17' into next 2014-11-19 21:32:12 +11:00
Linus Torvalds
5e40d331bd Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris.

Mostly ima, selinux, smack and key handling updates.

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (65 commits)
  integrity: do zero padding of the key id
  KEYS: output last portion of fingerprint in /proc/keys
  KEYS: strip 'id:' from ca_keyid
  KEYS: use swapped SKID for performing partial matching
  KEYS: Restore partial ID matching functionality for asymmetric keys
  X.509: If available, use the raw subjKeyId to form the key description
  KEYS: handle error code encoded in pointer
  selinux: normalize audit log formatting
  selinux: cleanup error reporting in selinux_nlmsg_perm()
  KEYS: Check hex2bin()'s return when generating an asymmetric key ID
  ima: detect violations for mmaped files
  ima: fix race condition on ima_rdwr_violation_check and process_measurement
  ima: added ima_policy_flag variable
  ima: return an error code from ima_add_boot_aggregate()
  ima: provide 'ima_appraise=log' kernel option
  ima: move keyring initialization to ima_init()
  PKCS#7: Handle PKCS#7 messages that contain no X.509 certs
  PKCS#7: Better handling of unsupported crypto
  KEYS: Overhaul key identification when searching for asymmetric keys
  KEYS: Implement binary asymmetric key ID handling
  ...
2014-10-12 10:13:55 -04:00
David Howells
0c903ab64f KEYS: Make the key matching functions return bool
Make the key matching functions pointed to by key_match_data::cmp return bool
rather than int.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-09-16 17:36:08 +01:00