Commit Graph

217 Commits

Author SHA1 Message Date
Linus Torvalds
67e2c38838 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security layer updates from James Morris:
 "In terms of changes, there's general maintenance to the Smack,
  SELinux, and integrity code.

  The IMA code adds a new kconfig option, IMA_APPRAISE_SIGNED_INIT,
  which allows IMA appraisal to require signatures.  Support for reading
  keys from rootfs before init is call is also added"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (23 commits)
  selinux: Remove security_ops extern
  security: smack: fix out-of-bounds access in smk_parse_smack()
  VFS: refactor vfs_read()
  ima: require signature based appraisal
  integrity: provide a hook to load keys when rootfs is ready
  ima: load x509 certificate from the kernel
  integrity: provide a function to load x509 certificate from the kernel
  integrity: define a new function integrity_read_file()
  Security: smack: replace kzalloc with kmem_cache for inode_smack
  Smack: Lock mode for the floor and hat labels
  ima: added support for new kernel cmdline parameter ima_template_fmt
  ima: allocate field pointers array on demand in template_desc_init_fields()
  ima: don't allocate a copy of template_fmt in template_desc_init_fields()
  ima: display template format in meas. list if template name length is zero
  ima: added error messages to template-related functions
  ima: use atomic bit operations to protect policy update interface
  ima: ignore empty and with whitespaces policy lines
  ima: no need to allocate entry for comment
  ima: report policy load status
  ima: use path names cache
  ...
2014-12-14 20:36:37 -08:00
Andrey Ryabinin
5c1b66240b security: smack: fix out-of-bounds access in smk_parse_smack()
Setting smack label on file (e.g. 'attr -S -s SMACK64 -V "test" test')
triggered following spew on the kernel with KASan applied:
    ==================================================================
    BUG: AddressSanitizer: out of bounds access in strncpy+0x28/0x60 at addr ffff8800059ad064
    =============================================================================
    BUG kmalloc-8 (Not tainted): kasan error
    -----------------------------------------------------------------------------

    Disabling lock debugging due to kernel taint
    INFO: Slab 0xffffea0000166b40 objects=128 used=7 fp=0xffff8800059ad080 flags=0x4000000000000080
    INFO: Object 0xffff8800059ad060 @offset=96 fp=0xffff8800059ad080

    Bytes b4 ffff8800059ad050: a0 df 9a 05 00 88 ff ff 5a 5a 5a 5a 5a 5a 5a 5a  ........ZZZZZZZZ
    Object ffff8800059ad060: 74 65 73 74 6b 6b 6b a5                          testkkk.
    Redzone ffff8800059ad068: cc cc cc cc cc cc cc cc                          ........
    Padding ffff8800059ad078: 5a 5a 5a 5a 5a 5a 5a 5a                          ZZZZZZZZ
    CPU: 0 PID: 528 Comm: attr Tainted: G    B          3.18.0-rc1-mm1+ #5
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
     0000000000000000 ffff8800059ad064 ffffffff81534cf2 ffff880005a5bc40
     ffffffff8112fe1a 0000000100800006 0000000f059ad060 ffff880006000f90
     0000000000000296 ffffea0000166b40 ffffffff8107ca97 ffff880005891060
    Call Trace:
    ? dump_stack (lib/dump_stack.c:52)
    ? kasan_report_error (mm/kasan/report.c:102 mm/kasan/report.c:178)
    ? preempt_count_sub (kernel/sched/core.c:2651)
    ? __asan_load1 (mm/kasan/kasan.h:50 mm/kasan/kasan.c:248 mm/kasan/kasan.c:358)
    ? strncpy (lib/string.c:121)
    ? strncpy (lib/string.c:121)
    ? smk_parse_smack (security/smack/smack_access.c:457)
    ? setxattr (fs/xattr.c:343)
    ? smk_import_entry (security/smack/smack_access.c:514)
    ? smack_inode_setxattr (security/smack/smack_lsm.c:1093 (discriminator 1))
    ? security_inode_setxattr (security/security.c:602)
    ? vfs_setxattr (fs/xattr.c:134)
    ? setxattr (fs/xattr.c:343)
    ? setxattr (fs/xattr.c:360)
    ? get_parent_ip (kernel/sched/core.c:2606)
    ? preempt_count_sub (kernel/sched/core.c:2651)
    ? __percpu_counter_add (arch/x86/include/asm/preempt.h:98 lib/percpu_counter.c:90)
    ? get_parent_ip (kernel/sched/core.c:2606)
    ? preempt_count_sub (kernel/sched/core.c:2651)
    ? __mnt_want_write (arch/x86/include/asm/preempt.h:98 fs/namespace.c:359)
    ? path_setxattr (fs/xattr.c:380)
    ? SyS_lsetxattr (fs/xattr.c:397)
    ? system_call_fastpath (arch/x86/kernel/entry_64.S:423)
    Read of size 1 by task attr:
    Memory state around the buggy address:
     ffff8800059ace80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
     ffff8800059acf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
     ffff8800059acf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    >ffff8800059ad000: 00 fc fc fc 00 fc fc fc 05 fc fc fc 04 fc fc fc
                                                           ^
     ffff8800059ad080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
     ffff8800059ad100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
     ffff8800059ad180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
    ==================================================================

strncpy() copies one byte more than the source string has.
Fix this by passing the correct length to strncpy().

Now we can remove initialization of the last byte in 'smack' string
because kzalloc() already did this for us.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
2014-11-21 13:14:22 -08:00
Al Viro
a455589f18 assorted conversions to %p[dD]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-19 13:01:20 -05:00
Rohit
1a5b472bde Security: smack: replace kzalloc with kmem_cache for inode_smack
The patch use kmem_cache to allocate/free inode_smack since they are
alloced in high volumes making it a perfect case for kmem_cache.

As per analysis, 24 bytes of memory is wasted per allocation due
to internal fragmentation. With kmem_cache, this can be avoided.

Accounting of memory allocation is below :
 total       slack            net      count-alloc/free        caller
Before (with kzalloc)
1919872      719952          1919872      29998/0          new_inode_smack+0x14

After (with kmem_cache)
1201680          0           1201680      30042/0          new_inode_smack+0x18

>From above data, we found that 719952 bytes(~700 KB) of memory is
saved on allocation of 29998 smack inodes.

Signed-off-by: Rohit <rohit.kr@samsung.com>
2014-10-31 14:29:32 -07:00
Casey Schaufler
6c892df268 Smack: Lock mode for the floor and hat labels
The lock access mode allows setting a read lock on a file
for with the process has only read access. The floor label is
defined to make it easy to have the basic system installed such
that everyone can read it. Once there's a desire to read lock
(rationally or otherwise) a floor file a rule needs to get set.
This happens all the time, so make the floor label a little bit
more special and allow everyone lock access, too. By implication,
give processes with the hat label (hat can read everything)
lock access as well. This reduces clutter in the Smack rule set.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2014-10-28 08:22:40 -07:00
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
Jeff Layton
e0b93eddfe security: make security_file_set_fowner, f_setown and __f_setown void return
security_file_set_fowner always returns 0, so make it f_setown and
__f_setown void return functions and fix up the error handling in the
callers.

Cc: linux-security-module@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2014-09-09 16:01:36 -04:00
Lukasz Pawelczyk
21c7eae21a Make Smack operate on smack_known struct where it still used char*
Smack used to use a mix of smack_known struct and char* throughout its
APIs and implementation. This patch unifies the behaviour and makes it
store and operate exclusively on smack_known struct pointers when managing
labels.

Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@samsung.com>

Conflicts:
	security/smack/smack_access.c
	security/smack/smack_lsm.c
2014-08-29 10:10:55 -07:00
Lukasz Pawelczyk
d01757904d Fix a bidirectional UDS connect check typo
The 54e70ec5eb commit introduced a
bidirectional check that should have checked for mutual WRITE access
between two labels. Due to a typo the second check was incorrect.

Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@samsung.com>
2014-08-29 10:10:47 -07:00
Lukasz Pawelczyk
e95ef49b7f Small fixes in comments describing function parameters
Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@samsung.com>
2014-08-29 10:10:36 -07:00
Casey Schaufler
d166c8024d Smack: Bring-up access mode
People keep asking me for permissive mode, and I keep saying "no".

Permissive mode is wrong for more reasons than I can enumerate,
but the compelling one is that it's once on, never off.

Nonetheless, there is an argument to be made for running a
process with lots of permissions, logging which are required,
and then locking the process down. There wasn't a way to do
that with Smack, but this provides it.

The notion is that you start out by giving the process an
appropriate Smack label, such as "ATBirds". You create rules
with a wide range of access and the "b" mode. On Tizen it
might be:

	ATBirds	System	rwxalb
	ATBirds	User	rwxalb
	ATBirds	_	rwxalb
	User	ATBirds	wb
	System	ATBirds	wb

Accesses that fail will generate audit records. Accesses
that succeed because of rules marked with a "b" generate
log messages identifying the rule, the program and as much
object information as is convenient.

When the system is properly configured and the programs
brought in line with the labeling scheme the "b" mode can
be removed from the rules. When the system is ready for
production the facility can be configured out.

This provides the developer the convenience of permissive
mode without creating a system that looks like it is
enforcing a policy while it is not.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2014-08-28 13:11:56 -07:00
Marcin Niesluchowski
d83d2c2646 Smack: Fix setting label on successful file open
While opening with CAP_MAC_OVERRIDE file label is not set.
Other calls may access it after CAP_MAC_OVERRIDE is dropped from process.

Signed-off-by: Marcin Niesluchowski <m.niesluchow@samsung.com>
2014-08-25 14:27:28 -07:00
Konstantin Khlebnikov
da1b63566c Smack: remove unneeded NULL-termination from securtity label
Values of extended attributes are stored as binary blobs. NULL-termination
of them isn't required. It just wastes disk space and confuses command-line
tools like getfattr because they have to print that zero byte at the end.

This patch removes terminating zero byte from initial security label in
smack_inode_init_security and cuts it out in function smack_inode_getsecurity
which is used by syscall getxattr. This change seems completely safe, because
function smk_parse_smack ignores everything after first zero byte.

Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
2014-08-08 14:51:19 -07:00
Konstantin Khlebnikov
b862e561ba Smack: handle zero-length security labels without panic
Zero-length security labels are invalid but kernel should handle them.

This patch fixes kernel panic after setting zero-length security labels:
# attr -S -s "SMACK64" -V "" file

And after writing zero-length string into smackfs files syslog and onlycp:
# python -c 'import os; os.write(1, "")' > /smack/syslog

The problem is caused by brain-damaged logic in function smk_parse_smack()
which takes pointer to buffer and its length but if length below or equal zero
it thinks that the buffer is zero-terminated. Unfortunately callers of this
function are widely used and proper fix requires serious refactoring.

Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
2014-08-08 14:51:07 -07:00
Konstantin Khlebnikov
fd5c9d230d Smack: fix behavior of smack_inode_listsecurity
Security operation ->inode_listsecurity is used for generating list of
available extended attributes for syscall listxattr. Currently it's used
only in nfs4 or if filesystem doesn't provide i_op->listxattr.

The list is the set of NULL-terminated names, one after the other.
This method must include zero byte at the and into result.

Also this function must return length even if string does not fit into
output buffer or it is NULL, see similar method in selinux and man listxattr.

Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
2014-08-08 14:50:19 -07:00
James Morris
103ae675b1 Merge branch 'next' of git://git.infradead.org/users/pcmoore/selinux into next 2014-08-02 22:58:02 +10:00
Paul Moore
4fbe63d1c7 netlabel: shorter names for the NetLabel catmap funcs/structs
Historically the NetLabel LSM secattr catmap functions and data
structures have had very long names which makes a mess of the NetLabel
code and anyone who uses NetLabel.  This patch renames the catmap
functions and structures from "*_secattr_catmap_*" to just "*_catmap_*"
which improves things greatly.

There are no substantial code or logic changes in this patch.

Signed-off-by: Paul Moore <pmoore@redhat.com>
Tested-by: Casey Schaufler <casey@schaufler-ca.com>
2014-08-01 11:17:37 -04:00
Paul Moore
4b8feff251 netlabel: fix the horribly broken catmap functions
The NetLabel secattr catmap functions, and the SELinux import/export
glue routines, were broken in many horrible ways and the SELinux glue
code fiddled with the NetLabel catmap structures in ways that we
probably shouldn't allow.  At some point this "worked", but that was
likely due to a bit of dumb luck and sub-par testing (both inflicted
by yours truly).  This patch corrects these problems by basically
gutting the code in favor of something less obtuse and restoring the
NetLabel abstractions in the SELinux catmap glue code.

Everything is working now, and if it decides to break itself in the
future this code will be much easier to debug than the code it
replaces.

One noteworthy side effect of the changes is that it is no longer
necessary to allocate a NetLabel catmap before calling one of the
NetLabel APIs to set a bit in the catmap.  NetLabel will automatically
allocate the catmap nodes when needed, resulting in less allocations
when the lowest bit is greater than 255 and less code in the LSMs.

Cc: stable@vger.kernel.org
Reported-by: Christian Evans <frodox@zoho.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Tested-by: Casey Schaufler <casey@schaufler-ca.com>
2014-08-01 11:17:17 -04:00
Paul Moore
41c3bd2039 netlabel: fix a problem when setting bits below the previously lowest bit
The NetLabel category (catmap) functions have a problem in that they
assume categories will be set in an increasing manner, e.g. the next
category set will always be larger than the last.  Unfortunately, this
is not a valid assumption and could result in problems when attempting
to set categories less than the startbit in the lowest catmap node.
In some cases kernel panics and other nasties can result.

This patch corrects the problem by checking for this and allocating a
new catmap node instance and placing it at the front of the list.

Cc: stable@vger.kernel.org
Reported-by: Christian Evans <frodox@zoho.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Tested-by: Casey Schaufler <casey@schaufler-ca.com>
2014-08-01 11:17:03 -04:00
James Morris
2fd4e6698f Merge branch 'smack-for-3.16' of git://git.gitorious.org/smack-next/kernel into next 2014-05-20 14:50:09 +10:00
Toralf Förster
ec554fa75e Warning in scanf string typing
This fixes a warning about the mismatch of types between
the declared unsigned and integer.

Signed-off-by: Toralf Förster <toralf.foerster@gmx.de>
2014-05-06 11:32:53 -07:00
Casey Schaufler
36ea735b52 Smack: Label cgroup files for systemd
The cgroup filesystem isn't ready for an LSM to
properly use extented attributes. This patch makes
files created in the cgroup filesystem usable by
a system running Smack and systemd.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2014-04-30 10:49:33 -07:00
Casey Schaufler
a6834c0b91 Smack: Verify read access on file open - v3
Smack believes that many of the operatons that can
be performed on an open file descriptor are read operations.
The fstat and lseek system calls are examples.
An implication of this is that files shouldn't be open
if the task doesn't have read access even if it has
write access and the file is being opened write only.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2014-04-23 08:52:39 -07:00
Casey Schaufler
54e70ec5eb Smack: bidirectional UDS connect check
Smack IPC policy requires that the sender have write access
to the receiver. UDS streams don't do per-packet checks. The
only check is done at connect time. The existing code checks
if the connecting process can write to the other, but not the
other way around. This change adds a check that the other end
can write to the connecting process.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schuafler <casey@schaufler-ca.com>
2014-04-11 14:35:28 -07:00
Casey Schaufler
f59bdfba3e Smack: Correctly remove SMACK64TRANSMUTE attribute
Sam Henderson points out that removing the SMACK64TRANSMUTE
attribute from a directory does not result in the directory
transmuting. This is because the inode flag indicating that
the directory is transmuting isn't cleared. The fix is a tad
less than trivial because smk_task and smk_mmap should have
been broken out, too.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2014-04-11 14:35:19 -07:00
José Bollo
9598f4c9e7 SMACK: Fix handling value==NULL in post setxattr
The function `smack_inode_post_setxattr` is called each
time that a setxattr is done, for any value of name.
The kernel allow to put value==NULL when size==0
to set an empty attribute value. The systematic
call to smk_import_entry was causing the dereference
of a NULL pointer hence a KERNEL PANIC!

The problem can be produced easily by issuing the
command `setfattr -n user.data file` under bash prompt
when SMACK is active.

Moving the call to smk_import_entry as proposed by this
patch is correcting the behaviour because the function
smack_inode_post_setxattr is called for the SMACK's
attributes only if the function smack_inode_setxattr validated
the value and its size (what will not be the case when size==0).

It also has a benefical effect to not fill the smack hash
with garbage values coming from any extended attribute
write.

Change-Id: Iaf0039c2be9bccb6cee11c24a3b44d209101fe47
Signed-off-by: José Bollo <jose.bollo@open.eurogiciel.org>
2014-04-11 14:35:05 -07:00
Pankaj Kumar
5e9ab593c2 bugfix patch for SMACK
1. In order to remove any SMACK extended attribute from a file, a user
should have CAP_MAC_ADMIN capability. But user without having this
capability is able to remove SMACK64MMAP security attribute.

2. While validating size and value of smack extended attribute in
smack_inode_setsecurity hook, wrong error code is returned.

Signed-off-by: Pankaj Kumar <pamkaj.k2@samsung.com>
Signed-off-by: Himanshu Shukla <himanshu.sh@samsung.com>
2014-04-11 14:34:52 -07:00
Lukasz Pawelczyk
6686781852 Smack: adds smackfs/ptrace interface
This allows to limit ptrace beyond the regular smack access rules.
It adds a smackfs/ptrace interface that allows smack to be configured
to require equal smack labels for PTRACE_MODE_ATTACH access.
See the changes in Documentation/security/Smack.txt below for details.

Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@partner.samsung.com>
Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2014-04-11 14:34:35 -07:00
Lukasz Pawelczyk
5663884caa Smack: unify all ptrace accesses in the smack
The decision whether we can trace a process is made in the following
functions:
	smack_ptrace_traceme()
	smack_ptrace_access_check()
	smack_bprm_set_creds() (in case the proces is traced)

This patch unifies all those decisions by introducing one function that
checks whether ptrace is allowed: smk_ptrace_rule_check().

This makes possible to actually trace with TRACEME where first the
TRACEME itself must be allowed and then exec() on a traced process.

Additional bugs fixed:
- The decision is made according to the mode parameter that is now correctly
  translated from PTRACE_MODE_* to MAY_* instead of being treated 1:1.
  PTRACE_MODE_READ requires MAY_READ.
  PTRACE_MODE_ATTACH requires MAY_READWRITE.
- Add a smack audit log in case of exec() refused by bprm_set_creds().
- Honor the PTRACE_MODE_NOAUDIT flag and don't put smack audit info
  in case this flag is set.

Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@partner.samsung.com>
Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2014-04-11 14:34:26 -07:00
Lukasz Pawelczyk
959e6c7f1e Smack: fix the subject/object order in smack_ptrace_traceme()
The order of subject/object is currently reversed in
smack_ptrace_traceme(). It is currently checked if the tracee has a
capability to trace tracer and according to this rule a decision is made
whether the tracer will be allowed to trace tracee.

Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@partner.samsung.com>
Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2014-04-11 14:34:17 -07:00
José Bollo
55dfc5da1a Minor improvement of 'smack_sb_kern_mount'
Fix a possible memory access fault when transmute is true and isp is NULL.

Signed-off-by: José Bollo <jose.bollo@open.eurogiciel.org>
2014-04-11 14:33:59 -07:00
Dmitry Kasatkin
fffea214ab smack: fix key permission verification
For any keyring access type SMACK always used MAY_READWRITE access check.
It prevents reading the key with label "_", which should be allowed for anyone.

This patch changes default access check to MAY_READ and use MAY_READWRITE in only
appropriate cases.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2014-03-14 17:44:49 +00:00
David Howells
f5895943d9 KEYS: Move the flags representing required permission to linux/key.h
Move the flags representing required permission to linux/key.h as the perm
parameter of security_key_permission() is in terms of them - and not the
permissions mask flags used in key->perm.

Whilst we're at it:

 (1) Rename them to be KEY_NEED_xxx rather than KEY_xxx to avoid collisions
     with symbols in uapi/linux/input.h.

 (2) Don't use key_perm_t for a mask of required permissions, but rather limit
     it to the permissions mask attached to the key and arguments related
     directly to that.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
2014-03-14 17:44:49 +00:00
Linus Torvalds
6dd9158ae8 Merge git://git.infradead.org/users/eparis/audit
Pull audit update from Eric Paris:
 "Again we stayed pretty well contained inside the audit system.
  Venturing out was fixing a couple of function prototypes which were
  inconsistent (didn't hurt anything, but we used the same value as an
  int, uint, u32, and I think even a long in a couple of places).

  We also made a couple of minor changes to when a couple of LSMs called
  the audit system.  We hoped to add aarch64 audit support this go
  round, but it wasn't ready.

  I'm disappearing on vacation on Thursday.  I should have internet
  access, but it'll be spotty.  If anything goes wrong please be sure to
  cc rgb@redhat.com.  He'll make fixing things his top priority"

* git://git.infradead.org/users/eparis/audit: (50 commits)
  audit: whitespace fix in kernel-parameters.txt
  audit: fix location of __net_initdata for audit_net_ops
  audit: remove pr_info for every network namespace
  audit: Modify a set of system calls in audit class definitions
  audit: Convert int limit uses to u32
  audit: Use more current logging style
  audit: Use hex_byte_pack_upper
  audit: correct a type mismatch in audit_syscall_exit()
  audit: reorder AUDIT_TTY_SET arguments
  audit: rework AUDIT_TTY_SET to only grab spin_lock once
  audit: remove needless switch in AUDIT_SET
  audit: use define's for audit version
  audit: documentation of audit= kernel parameter
  audit: wait_for_auditd rework for readability
  audit: update MAINTAINERS
  audit: log task info on feature change
  audit: fix incorrect set of audit_sock
  audit: print error message when fail to create audit socket
  audit: fix dangling keywords in audit_log_set_loginuid() output
  audit: log on errors from filter user rules
  ...
2014-01-23 18:08:10 -08:00
Richard Guy Briggs
4eb0f4abfb smack: call WARN_ONCE() instead of calling audit_log_start()
Remove the call to audit_log() (which call audit_log_start()) and deal with
the errors in the caller, logging only once if the condition is met.  Calling
audit_log_start() in this location makes buffer allocation and locking more
complicated in the calling tree (audit_filter_user()).

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:32:06 -05:00
Casey Schaufler
4482a44f6a Smack: File receive audit correction
Eric Paris politely points out:

    Inside smack_file_receive() it seems like you are initting the audit
    field with LSM_AUDIT_DATA_TASK.  And then use
    smk_ad_setfield_u_fs_path().

    Seems like LSM_AUDIT_DATA_PATH would make more sense.  (and depending
    on how it's used fix a crash...)

He is correct. This puts things in order.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-12-31 13:35:27 -08:00
Casey Schaufler
24ea1b6efc Smack: Rationalize mount restrictions
The mount restrictions imposed by Smack rely heavily on the
use of the filesystem "floor", which is the label that all
processes writing to the filesystem must have access to. It
turns out that while the "floor" notion is sound, it has yet
to be fully implemented and has never been used.

The sb_mount and sb_umount hooks only make sense if the
filesystem floor is used actively, and it isn't. They can
be reintroduced if a rational restriction comes up. Until
then, they get removed.

The sb_kern_mount hook is required for the option processing.
It is too permissive in the case of unprivileged mounts,
effectively bypassing the CAP_MAC_ADMIN restrictions if
any of the smack options are specified. Unprivileged mounts
are no longer allowed to set Smack filesystem options.
Additionally, the root and default values are set to the
label of the caller, in keeping with the policy that objects
get the label of their creator.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-12-31 13:35:16 -08:00
Casey Schaufler
4afde48be8 Smack: change rule cap check
smk_write_change_rule() is calling capable rather than
the more correct smack_privileged(). This allows for setting
rules in violation of the onlycap facility. This is the
simple repair.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-12-23 15:57:43 -08:00
Casey Schaufler
00f84f3f2e Smack: Make the syslog control configurable
The syslog control requires that the calling proccess
have the floor ("_") Smack label. Tizen does not run any
processes except for kernel helpers with the floor label.
This changes allows the admin to configure a specific
label for syslog. The default value is the star ("*")
label, effectively removing the restriction. The value
can be set using smackfs/syslog for anyone who wants
a more restrictive behavior.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-12-23 15:50:55 -08:00
Casey Schaufler
19760ad03c Smack: Prevent the * and @ labels from being used in SMACK64EXEC
Smack prohibits processes from using the star ("*") and web ("@") labels
because we don't want files with those labels getting created implicitly.
All setting of those labels should be done explicitly. The trouble is that
there is no check for these labels in the processing of SMACK64EXEC. That
is repaired.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-12-19 13:05:24 -08:00
Jarkko Sakkinen
398ce07370 smack: fix: allow either entry be missing on access/access2 check (v2)
This is a regression caused by f7112e6c. When either subject or
object is not found the answer for access should be no. This
patch fixes the situation. '0' is written back instead of failing
with -EINVAL.

v2: cosmetic style fixes

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2013-12-11 10:48:55 -08:00
Casey Schaufler
b5dfd8075b Smack: Ptrace access check mode
When the ptrace security hooks were split the addition of
a mode parameter was not taken advantage of in the Smack
ptrace access check. This changes the access check from
always looking for read and write access to using the
passed mode. This will make use of /proc much happier.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-10-28 10:23:36 -07:00
Casey Schaufler
c0ab6e56dc Smack: Implement lock security mode
Linux file locking does not follow the same rules
as other mechanisms. Even though it is a write operation
a process can set a read lock on files which it has open
only for read access. Two programs with read access to
a file can use read locks to communicate.

This is not acceptable in a Mandatory Access Control
environment. Smack treats setting a read lock as the
write operation that it is. Unfortunately, many programs
assume that setting a read lock is a read operation.
These programs are unhappy in the Smack environment.

This patch introduces a new access mode (lock) to address
this problem. A process with lock access to a file can
set a read lock. A process with write access to a file can
set a read lock or a write lock. This prevents a situation
where processes are granted write access just so they can
set read locks.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-10-18 09:39:33 -07:00
Linus Torvalds
11c7b03d42 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "Nothing major for this kernel, just maintenance updates"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (21 commits)
  apparmor: add the ability to report a sha1 hash of loaded policy
  apparmor: export set of capabilities supported by the apparmor module
  apparmor: add the profile introspection file to interface
  apparmor: add an optional profile attachment string for profiles
  apparmor: add interface files for profiles and namespaces
  apparmor: allow setting any profile into the unconfined state
  apparmor: make free_profile available outside of policy.c
  apparmor: rework namespace free path
  apparmor: update how unconfined is handled
  apparmor: change how profile replacement update is done
  apparmor: convert profile lists to RCU based locking
  apparmor: provide base for multiple profiles to be replaced at once
  apparmor: add a features/policy dir to interface
  apparmor: enable users to query whether apparmor is enabled
  apparmor: remove minimum size check for vmalloc()
  Smack: parse multiple rules per write to load2, up to PAGE_SIZE-1 bytes
  Smack: network label match fix
  security: smack: add a hash table to quicken smk_find_entry()
  security: smack: fix memleak in smk_write_rules_list()
  xattr: Constify ->name member of "struct xattr".
  ...
2013-09-07 14:34:07 -07:00
James Morris
7320336146 Merge branch 'smack-for-3.12' of git://git.gitorious.org/smack-next/kernel into ra-next 2013-08-23 02:50:12 +10:00
Rafal Krypa
10289b0f73 Smack: parse multiple rules per write to load2, up to PAGE_SIZE-1 bytes
Smack interface for loading rules has always parsed only single rule from
data written to it. This requires user program to call one write() per
each rule it wants to load.
This change makes it possible to write multiple rules, separated by new
line character. Smack will load at most PAGE_SIZE-1 characters and properly
return number of processed bytes. In case when user buffer is larger, it
will be additionally truncated. All characters after last \n will not get
parsed to avoid partial rule near input buffer boundary.

Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2013-08-12 11:51:40 -07:00
Casey Schaufler
6ea062475a Smack: IPv6 casting error fix for 3.11
The original implementation of the Smack IPv6 port based
local controls works most of the time using a sockaddr as
a temporary variable, but not always as it overflows in
some circumstances. The correct data is a sockaddr_in6.
A struct sockaddr isn't as large as a struct sockaddr_in6.
There would need to be casting one way or the other. This
patch gets it the right way.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-08-06 20:53:54 +10:00
Casey Schaufler
677264e8fb Smack: network label match fix
The Smack code that matches incoming CIPSO tags with Smack labels
reaches through the NetLabel interfaces and compares the network
data with the CIPSO header associated with a Smack label. This was
done in a ill advised attempt to optimize performance. It works
so long as the categories fit in a single capset, but this isn't
always the case.

This patch changes the Smack code to use the appropriate NetLabel
interfaces to compare the incoming CIPSO header with the CIPSO
header associated with a label. It will always match the CIPSO
headers correctly.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2013-08-01 20:04:02 -07:00
Tomasz Stanislawski
4d7cf4a1f4 security: smack: add a hash table to quicken smk_find_entry()
Accepted for the smack-next tree after changing the number of
slots from 128 to 16.

This patch adds a hash table to quicken searching of a smack label by its name.

Basically, the patch improves performance of SMACK initialization.  Parsing of
rules involves translation from a string to a smack_known (aka label) entity
which is done in smk_find_entry().

The current implementation of the function iterates over a global list of
smack_known resulting in O(N) complexity for smk_find_entry().  The total
complexity of SMACK initialization becomes O(rules * labels).  Therefore it
scales quadratically with a complexity of a system.

Applying the patch reduced the complexity of smk_find_entry() to O(1) as long
as number of label is in hundreds. If the number of labels is increased please
update SMACK_HASH_SLOTS constant defined in security/smack/smack.h. Introducing
the configuration of this constant with Kconfig or cmdline might be a good
idea.

The size of the hash table was adjusted experimentally.  The rule set used by
TIZEN contains circa 17K rules for 500 labels.  The table above contains
results of SMACK initialization using 'time smackctl apply' bash command.
The 'Ref' is a kernel without this patch applied. The consecutive values
refers to value of SMACK_HASH_SLOTS.  Every measurement was repeated three
times to reduce noise.

     |  Ref  |   1   |   2   |   4   |   8   |   16  |   32  |   64  |  128  |  256  |  512
--------------------------------------------------------------------------------------------
Run1 | 1.156 | 1.096 | 0.883 | 0.764 | 0.692 | 0.667 | 0.649 | 0.633 | 0.634 | 0.629 | 0.620
Run2 | 1.156 | 1.111 | 0.885 | 0.764 | 0.694 | 0.661 | 0.649 | 0.651 | 0.634 | 0.638 | 0.623
Run3 | 1.160 | 1.107 | 0.886 | 0.764 | 0.694 | 0.671 | 0.661 | 0.638 | 0.631 | 0.624 | 0.638
AVG  | 1.157 | 1.105 | 0.885 | 0.764 | 0.693 | 0.666 | 0.653 | 0.641 | 0.633 | 0.630 | 0.627

Surprisingly, a single hlist is slightly faster than a double-linked list.
The speed-up saturates near 64 slots.  Therefore I chose value 128 to provide
some margin if more labels were used.
It looks that IO becomes a new bottleneck.

Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com>
2013-08-01 16:55:20 -07:00
Tomasz Stanislawski
470043ba99 security: smack: fix memleak in smk_write_rules_list()
The smack_parsed_rule structure is allocated.  If a rule is successfully
installed then the last reference to the object is lost.  This patch fixes this
leak. Moreover smack_parsed_rule is allocated on stack because it no longer
needed ofter smk_write_rules_list() is finished.

Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com>
2013-08-01 12:57:24 -07:00