Commit Graph

35 Commits

Author SHA1 Message Date
Tyler Hicks
7f3ebcf2b1 apparmor: Check buffer bounds when mapping permissions mask
Don't read past the end of the buffer containing permissions
characters or write past the end of the destination string.

Detected by CoverityScan CID#1415361, 1415376 ("Out-of-bounds access")

Fixes: e53cfe6c7c ("apparmor: rework perm mapping to a slightly broader set")
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-07-19 16:24:43 -07:00
John Johansen
56974a6fcf apparmor: add base infastructure for socket mediation
version 2 - Force an abi break. Network mediation will only be
            available in v8 abi complaint policy.

Provide a basic mediation of sockets. This is not a full net mediation
but just whether a spcific family of socket can be used by an
application, along with setting up some basic infrastructure for
network mediation to follow.

the user space rule hav the basic form of
  NETWORK RULE = [ QUALIFIERS ] 'network' [ DOMAIN ]
                 [ TYPE | PROTOCOL ]

  DOMAIN = ( 'inet' | 'ax25' | 'ipx' | 'appletalk' | 'netrom' |
             'bridge' | 'atmpvc' | 'x25' | 'inet6' | 'rose' |
	     'netbeui' | 'security' | 'key' | 'packet' | 'ash' |
	     'econet' | 'atmsvc' | 'sna' | 'irda' | 'pppox' |
	     'wanpipe' | 'bluetooth' | 'netlink' | 'unix' | 'rds' |
	     'llc' | 'can' | 'tipc' | 'iucv' | 'rxrpc' | 'isdn' |
	     'phonet' | 'ieee802154' | 'caif' | 'alg' | 'nfc' |
	     'vsock' | 'mpls' | 'ib' | 'kcm' ) ','

  TYPE = ( 'stream' | 'dgram' | 'seqpacket' |  'rdm' | 'raw' |
           'packet' )

  PROTOCOL = ( 'tcp' | 'udp' | 'icmp' )

eg.
  network,
  network inet,

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2018-03-13 17:25:48 -07:00
John Johansen
d8889d49e4 apparmor: move context.h to cred.h
Now that file contexts have been moved into file, and task context
fns() and data have been split from the context, only the cred context
remains in context.h so rename to cred.h to better reflect what it
deals with.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-02-09 11:30:01 -08:00
Arnd Bergmann
7bba39ae52 apparmor: initialized returned struct aa_perms
gcc-4.4 points out suspicious code in compute_mnt_perms, where
the aa_perms structure is only partially initialized before getting
returned:

security/apparmor/mount.c: In function 'compute_mnt_perms':
security/apparmor/mount.c:227: error: 'perms.prompt' is used uninitialized in this function
security/apparmor/mount.c:227: error: 'perms.hide' is used uninitialized in this function
security/apparmor/mount.c:227: error: 'perms.cond' is used uninitialized in this function
security/apparmor/mount.c:227: error: 'perms.complain' is used uninitialized in this function
security/apparmor/mount.c:227: error: 'perms.stop' is used uninitialized in this function
security/apparmor/mount.c:227: error: 'perms.deny' is used uninitialized in this function

Returning or assigning partially initialized structures is a bit tricky,
in particular it is explicitly allowed in c99 to assign a partially
initialized structure to another, as long as only members are read that
have been initialized earlier. Looking at what various compilers do here,
the version that produced the warning copied uninitialized stack data,
while newer versions (and also clang) either set the other members to
zero or don't update the parts of the return buffer that are not modified
in the temporary structure, but they never warn about this.

In case of apparmor, it seems better to be a little safer and always
initialize the aa_perms structure. Most users already do that, this
changes the remaining ones, including the one instance that I got the
warning for.

Fixes: fa488437d0f9 ("apparmor: add mount mediation")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-11-21 02:15:50 -08:00
Linus Torvalds
80c094a47d Revert "apparmor: add base infastructure for socket mediation"
This reverts commit 651e28c553.

This caused a regression:
 "The specific problem is that dnsmasq refuses to start on openSUSE Leap
  42.2.  The specific cause is that and attempt to open a PF_LOCAL socket
  gets EACCES.  This means that networking doesn't function on a system
  with a 4.14-rc2 system."

Sadly, the developers involved seemed to be in denial for several weeks
about this, delaying the revert.  This has not been a good release for
the security subsystem, and this area needs to change development
practices.

Reported-and-bisected-by: James Bottomley <James.Bottomley@hansenpartnership.com>
Tracked-by: Thorsten Leemhuis <regressions@leemhuis.info>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Seth Arnold <seth.arnold@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-26 19:35:35 +02:00
John Johansen
651e28c553 apparmor: add base infastructure for socket mediation
Provide a basic mediation of sockets. This is not a full net mediation
but just whether a spcific family of socket can be used by an
application, along with setting up some basic infrastructure for
network mediation to follow.

the user space rule hav the basic form of
  NETWORK RULE = [ QUALIFIERS ] 'network' [ DOMAIN ]
                 [ TYPE | PROTOCOL ]

  DOMAIN = ( 'inet' | 'ax25' | 'ipx' | 'appletalk' | 'netrom' |
             'bridge' | 'atmpvc' | 'x25' | 'inet6' | 'rose' |
	     'netbeui' | 'security' | 'key' | 'packet' | 'ash' |
	     'econet' | 'atmsvc' | 'sna' | 'irda' | 'pppox' |
	     'wanpipe' | 'bluetooth' | 'netlink' | 'unix' | 'rds' |
	     'llc' | 'can' | 'tipc' | 'iucv' | 'rxrpc' | 'isdn' |
	     'phonet' | 'ieee802154' | 'caif' | 'alg' | 'nfc' |
	     'vsock' | 'mpls' | 'ib' | 'kcm' ) ','

  TYPE = ( 'stream' | 'dgram' | 'seqpacket' |  'rdm' | 'raw' |
           'packet' )

  PROTOCOL = ( 'tcp' | 'udp' | 'icmp' )

eg.
  network,
  network inet,

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2017-09-22 13:00:58 -07:00
Stephen Rothwell
c4758fa592 apparmor: put back designators in struct initialisers
Fixes: 8014370f12 ("apparmor: move path_link mediation to using labels")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-06-28 15:50:43 +10:00
John Johansen
496c931966 apparmor: rework file permission to cache file access in file->ctx
This is a temporary step, towards using the file->ctx for delegation,
and also helps speed up file queries, until the permission lookup
cache is introduced.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-10 17:11:44 -07:00
John Johansen
8014370f12 apparmor: move path_link mediation to using labels
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-10 17:11:44 -07:00
John Johansen
aebd873e8d apparmor: refactor path name lookup and permission checks around labels
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-10 17:11:43 -07:00
John Johansen
98c3d18232 apparmor: update aa_audit_file() to use labels
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-10 17:11:43 -07:00
John Johansen
190a95189e apparmor: move aa_file_perm() to use labels
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-10 17:11:42 -07:00
John Johansen
637f688dc3 apparmor: switch from profiles to using labels on contexts
Begin the actual switch to using domain labels by storing them on
the context and converting the label to a singular profile where
possible.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-10 17:11:38 -07:00
John Johansen
192ca6b55a apparmor: revalidate files during exec
Instead of running file revalidation lazily when read/write are called
copy selinux and revalidate the file table on exec. This avoids
extra mediation overhead in read/write and also prevents file handles
being passed through to a grand child unchecked.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-10 17:11:37 -07:00
John Johansen
2d679f3cb0 apparmor: switch from file_perms to aa_perms
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-10 17:11:30 -07:00
John Johansen
aa9aeea8d4 apparmor: add gerneric permissions struct and support fns
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-10 17:11:30 -07:00
John Johansen
e53cfe6c7c apparmor: rework perm mapping to a slightly broader set
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-09 05:59:22 -07:00
John Johansen
4227c333f6 apparmor: Move path lookup to using preallocated buffers
Dynamically allocating buffers is problematic and is an extra layer
that is a potntial point of failure and can slow down mediation.
Change path lookup to use the preallocated per cpu buffers.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-08 11:29:34 -07:00
John Johansen
72c8a76864 apparmor: allow profiles to provide info to disconnected paths
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-08 11:29:34 -07:00
John Johansen
ef88a7ac55 apparmor: change aad apparmor_audit_data macro to a fn macro
The aad macro can replace aad strings when it is not intended to. Switch
to a fn macro so it is only applied when intended.

Also at the same time cleanup audit_data initialization by putting
common boiler plate behind a macro, and dropping the gfp_t parameter
which will become useless.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:47 -08:00
John Johansen
47f6e5cc73 apparmor: change op from int to const char *
Having ops be an integer that is an index into an op name table is
awkward and brittle. Every op change requires an edit for both the
op constant and a string in the table. Instead switch to using const
strings directly, eliminating the need for the table that needs to
be kept in sync.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:46 -08:00
Kees Cook
8486adf0d7 apparmor: use designated initializers
Prepare to mark sensitive kernel structures for randomization by making
sure they're using designated initializers. These were identified during
allyesconfig builds of x86, arm, and arm64, with most initializer fixes
extracted from grsecurity.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-15 20:00:32 -08:00
John Johansen
b6b1b81b3a apparmor: fix uninitialized lsm_audit member
BugLink: http://bugs.launchpad.net/bugs/1268727

The task field in the lsm_audit struct needs to be initialized if
a change_hat fails, otherwise the following oops will occur

BUG: unable to handle kernel paging request at 0000002fbead7d08
IP: [<ffffffff8171153e>] _raw_spin_lock+0xe/0x50
PGD 1e3f35067 PUD 0
Oops: 0002 [#1] SMP
Modules linked in: pppox crc_ccitt p8023 p8022 psnap llc ax25 btrfs raid6_pq xor xfs libcrc32c dm_multipath scsi_dh kvm_amd dcdbas kvm microcode amd64_edac_mod joydev edac_core psmouse edac_mce_amd serio_raw k10temp sp5100_tco i2c_piix4 ipmi_si ipmi_msghandler acpi_power_meter mac_hid lp parport hid_generic usbhid hid pata_acpi mpt2sas ahci raid_class pata_atiixp bnx2 libahci scsi_transport_sas [last unloaded: tipc]
CPU: 2 PID: 699 Comm: changehat_twice Tainted: GF          O 3.13.0-7-generic #25-Ubuntu
Hardware name: Dell Inc. PowerEdge R415/08WNM9, BIOS 1.8.6 12/06/2011
task: ffff8802135c6000 ti: ffff880212986000 task.ti: ffff880212986000
RIP: 0010:[<ffffffff8171153e>]  [<ffffffff8171153e>] _raw_spin_lock+0xe/0x50
RSP: 0018:ffff880212987b68  EFLAGS: 00010006
RAX: 0000000000020000 RBX: 0000002fbead7500 RCX: 0000000000000000
RDX: 0000000000000292 RSI: ffff880212987ba8 RDI: 0000002fbead7d08
RBP: ffff880212987b68 R08: 0000000000000246 R09: ffff880216e572a0
R10: ffffffff815fd677 R11: ffffea0008469580 R12: ffffffff8130966f
R13: ffff880212987ba8 R14: 0000002fbead7d08 R15: ffff8800d8c6b830
FS:  00002b5e6c84e7c0(0000) GS:ffff880216e40000(0000) knlGS:0000000055731700
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000002fbead7d08 CR3: 000000021270f000 CR4: 00000000000006e0
Stack:
 ffff880212987b98 ffffffff81075f17 ffffffff8130966f 0000000000000009
 0000000000000000 0000000000000000 ffff880212987bd0 ffffffff81075f7c
 0000000000000292 ffff880212987c08 ffff8800d8c6b800 0000000000000026
Call Trace:
 [<ffffffff81075f17>] __lock_task_sighand+0x47/0x80
 [<ffffffff8130966f>] ? apparmor_cred_prepare+0x2f/0x50
 [<ffffffff81075f7c>] do_send_sig_info+0x2c/0x80
 [<ffffffff81075fee>] send_sig_info+0x1e/0x30
 [<ffffffff8130242d>] aa_audit+0x13d/0x190
 [<ffffffff8130c1dc>] aa_audit_file+0xbc/0x130
 [<ffffffff8130966f>] ? apparmor_cred_prepare+0x2f/0x50
 [<ffffffff81304cc2>] aa_change_hat+0x202/0x530
 [<ffffffff81308fc6>] aa_setprocattr_changehat+0x116/0x1d0
 [<ffffffff8130a11d>] apparmor_setprocattr+0x25d/0x300
 [<ffffffff812cee56>] security_setprocattr+0x16/0x20
 [<ffffffff8121fc87>] proc_pid_attr_write+0x107/0x130
 [<ffffffff811b7604>] vfs_write+0xb4/0x1f0
 [<ffffffff811b8039>] SyS_write+0x49/0xa0
 [<ffffffff8171a1bf>] tracesys+0xe1/0xe6

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2016-07-12 08:43:10 -07:00
Al Viro
3539aaf670 apparmor: constify aa_path_link()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-03-28 00:47:26 -04:00
Al Viro
2c7661ff41 [apparmor] constify struct path * in a bunch of helpers
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-03-27 23:48:14 -04:00
David Howells
c6f493d631 VFS: security/: d_backing_inode() annotations
most of the ->d_inode uses there refer to the same inode IO would
go to, i.e. d_backing_inode()

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:56 -04:00
Al Viro
496ad9aa8e new helper: file_inode(file)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22 23:31:31 -05:00
Eric W. Biederman
2db8145293 userns: Convert apparmor to use kuid and kgid where appropriate
Cc: John Johansen <john.johansen@canonical.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-09-21 03:13:21 -07:00
Eric Paris
50c205f5e5 LSM: do not initialize common_audit_data to 0
It isn't needed.  If you don't set the type of the data associated with
that type it is a pretty obvious programming bug.  So why waste the cycles?

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:04 -04:00
Eric Paris
bd5e50f9c1 LSM: remove the COMMON_AUDIT_DATA_INIT type expansion
Just open code it so grep on the source code works better.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:01 -04:00
Eric Paris
3b3b0e4fc1 LSM: shrink sizeof LSM specific portion of common_audit_data
Linus found that the gigantic size of the common audit data caused a big
perf hit on something as simple as running stat() in a loop.  This patch
requires LSMs to declare the LSM specific portion separately rather than
doing it in a union.  Thus each LSM can be responsible for shrinking their
portion and don't have to pay a penalty just because other LSMs have a
bigger space requirement.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-03 09:48:40 -07:00
John Johansen
0421ea91dd apparmor: Fix change_onexec when called from a confined task
Fix failure in aa_change_onexec api when the request is made from a confined
task.  This failure was caused by two problems

 The AA_MAY_ONEXEC perm was not being mapped correctly for this case.

 The executable name was being checked as second time instead of using the
 requested onexec profile name, which may not be the same as the exec
 profile name. This mistake can not be exploited to grant extra permission
 because of the above flaw where the ONEXEC permission was not being mapped
 so it will not be granted.

BugLink: http://bugs.launchpad.net/bugs/963756

Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-03-28 01:00:05 +11:00
John Johansen
57fa1e1809 AppArmor: Move path failure information into aa_get_name and rename
Move the path name lookup failure messages into the main path name lookup
routine, as the information is useful in more than just aa_path_perm.

Also rename aa_get_name to aa_path_name as it is not getting a reference
counted object with a corresponding put fn.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
2012-03-14 06:15:25 -07:00
John Johansen
38305a4bab AppArmor: fix mapping of META_READ to audit and quiet flags
The mapping of AA_MAY_META_READ for the allow mask was also being mapped
to the audit and quiet masks. This would result in some operations being
audited when the should not.

This flaw was hidden by the previous audit bug which would drop some
messages that where supposed to be audited.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
2012-02-27 11:38:22 -08:00
John Johansen
6380bd8ddf AppArmor: file enforcement routines
AppArmor does files enforcement via pathname matching.  Matching is done
at file open using a dfa match engine.  Permission is against the final
file object not parent directories, ie. the traversal of directories
as part of the file match is implicitly allowed.  In the case of nonexistant
files (creation) permissions are checked against the target file not the
directory.  eg. In case of creating the file /dir/new, permissions are
checked against the match /dir/new not against /dir/.

The permissions for matches are currently stored in the dfa accept table,
but this will change to allow for dfa reuse and also to allow for sharing
of wider accept states.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:35:14 +10:00