Commit Graph

18 Commits

Author SHA1 Message Date
John Johansen feb3c766a3 apparmor: fix possible recursive lock warning in __aa_create_ns
Use mutex_lock_nested to provide lockdep the parent child lock ordering of
the tree.

This fixes the lockdep Warning
[  305.275177] ============================================
[  305.275178] WARNING: possible recursive locking detected
[  305.275179] 4.14.0-rc7+ #320 Not tainted
[  305.275180] --------------------------------------------
[  305.275181] apparmor_parser/1339 is trying to acquire lock:
[  305.275182]  (&ns->lock){+.+.}, at: [<ffffffff970544dd>] __aa_create_ns+0x6d/0x1e0
[  305.275187]
               but task is already holding lock:
[  305.275187]  (&ns->lock){+.+.}, at: [<ffffffff97054b5d>] aa_prepare_ns+0x3d/0xd0
[  305.275190]
               other info that might help us debug this:
[  305.275191]  Possible unsafe locking scenario:

[  305.275192]        CPU0
[  305.275193]        ----
[  305.275193]   lock(&ns->lock);
[  305.275194]   lock(&ns->lock);
[  305.275195]
                *** DEADLOCK ***

[  305.275196]  May be due to missing lock nesting notation

[  305.275198] 2 locks held by apparmor_parser/1339:
[  305.275198]  #0:  (sb_writers#10){.+.+}, at: [<ffffffff96e9c6b7>] vfs_write+0x1a7/0x1d0
[  305.275202]  #1:  (&ns->lock){+.+.}, at: [<ffffffff97054b5d>] aa_prepare_ns+0x3d/0xd0
[  305.275205]
               stack backtrace:
[  305.275207] CPU: 1 PID: 1339 Comm: apparmor_parser Not tainted 4.14.0-rc7+ #320
[  305.275208] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1ubuntu1 04/01/2014
[  305.275209] Call Trace:
[  305.275212]  dump_stack+0x85/0xcb
[  305.275214]  __lock_acquire+0x141c/0x1460
[  305.275216]  ? __aa_create_ns+0x6d/0x1e0
[  305.275218]  ? ___slab_alloc+0x183/0x540
[  305.275219]  ? ___slab_alloc+0x183/0x540
[  305.275221]  lock_acquire+0xed/0x1e0
[  305.275223]  ? lock_acquire+0xed/0x1e0
[  305.275224]  ? __aa_create_ns+0x6d/0x1e0
[  305.275227]  __mutex_lock+0x89/0x920
[  305.275228]  ? __aa_create_ns+0x6d/0x1e0
[  305.275230]  ? trace_hardirqs_on_caller+0x11f/0x190
[  305.275231]  ? __aa_create_ns+0x6d/0x1e0
[  305.275233]  ? __lockdep_init_map+0x57/0x1d0
[  305.275234]  ? lockdep_init_map+0x9/0x10
[  305.275236]  ? __rwlock_init+0x32/0x60
[  305.275238]  mutex_lock_nested+0x1b/0x20
[  305.275240]  ? mutex_lock_nested+0x1b/0x20
[  305.275241]  __aa_create_ns+0x6d/0x1e0
[  305.275243]  aa_prepare_ns+0xc2/0xd0
[  305.275245]  aa_replace_profiles+0x168/0xf30
[  305.275247]  ? __might_fault+0x85/0x90
[  305.275250]  policy_update+0xb9/0x380
[  305.275252]  profile_load+0x7e/0x90
[  305.275254]  __vfs_write+0x28/0x150
[  305.275256]  ? rcu_read_lock_sched_held+0x72/0x80
[  305.275257]  ? rcu_sync_lockdep_assert+0x2f/0x60
[  305.275259]  ? __sb_start_write+0xdc/0x1c0
[  305.275261]  ? vfs_write+0x1a7/0x1d0
[  305.275262]  vfs_write+0xca/0x1d0
[  305.275264]  ? trace_hardirqs_on_caller+0x11f/0x190
[  305.275266]  SyS_write+0x49/0xa0
[  305.275268]  entry_SYSCALL_64_fastpath+0x23/0xc2
[  305.275271] RIP: 0033:0x7fa6b22e8c74
[  305.275272] RSP: 002b:00007ffeaaee6288 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[  305.275273] RAX: ffffffffffffffda RBX: 00007ffeaaee62a4 RCX: 00007fa6b22e8c74
[  305.275274] RDX: 0000000000000a51 RSI: 00005566a8198c10 RDI: 0000000000000004
[  305.275275] RBP: 0000000000000a39 R08: 0000000000000a51 R09: 0000000000000000
[  305.275276] R10: 0000000000000000 R11: 0000000000000246 R12: 00005566a8198c10
[  305.275277] R13: 0000000000000004 R14: 00005566a72ecb88 R15: 00005566a72ec3a8

Fixes: 73688d1ed0 ("apparmor: refactor prepare_ns() and make usable from different views")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-11-21 02:17:16 -08:00
John Johansen 15372b97aa apparmor: ensure unconfined profiles have dfas initialized
Generally unconfined has early bailout tests and does not need the
dfas initialized, however if an early bailout test is ever missed
it will result in an oops.

Be defensive and initialize the unconfined profile to have null dfas
(no permission) so if an early bailout test is missed we fail
closed (no perms granted) instead of oopsing.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-09-22 13:00:58 -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 3664268f19 apparmor: add namespace lookup fns()
Currently lookups are restricted to a single ns component in the
path. However when namespaces are allowed to have separate views, and
scopes this will not be sufficient, as it will be possible to have
a multiple component ns path in scope.

Add some ns lookup fns() to allow this and use them.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-10 17:11:32 -07:00
John Johansen d9bf2c268b apparmor: add policy revision file interface
Add a policy revision file to find the current revision of a ns's policy.
There is a revision file per ns, as well as a virtualized global revision
file in the base apparmor fs directory. The global revision file when
opened will provide the revision of the opening task namespace.

The revision file can be waited on via select/poll to detect apparmor
policy changes from the last read revision of the opened file. This
means that the revision file must be read after the select/poll other
wise update data will remain ready for reading.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-06-10 17:11:27 -07:00
John Johansen 98407f0a0d apparmor: allow specifying an already created dir to create ns entries in
Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2017-06-08 12:51:52 -07:00
John Johansen c97204baf8 apparmor: rename apparmor file fns and data to indicate use
prefixes are used for fns/data that are not static to apparmorfs.c
with the prefixes being
  aafs   - special magic apparmorfs for policy namespace data
  aa_sfs - for fns/data that go into securityfs
  aa_fs  - for fns/data that may be used in the either of aafs or
           securityfs

Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2017-06-08 12:51:52 -07:00
John Johansen 5d5182cae4 apparmor: move to per loaddata files, instead of replicating in profiles
The loaddata sets cover more than just a single profile and should
be tracked at the ns level. Move the load data files under the namespace
and reference the files from the profiles via a symlink.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2017-06-08 12:51:49 -07:00
John Johansen ee2351e4b0 apparmor: track ns level so it can be used to help in view checks
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:36 -08:00
John Johansen 30b026a8d1 apparmor: pass gfp_t parameter into profile allocation
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:29 -08:00
John Johansen 73688d1ed0 apparmor: refactor prepare_ns() and make usable from different views
prepare_ns() will need to be called from alternate views, and namespaces
will need to be created via different interfaces. So refactor and
allow specifying the view ns.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:28 -08:00
John Johansen d102d89571 apparmor: pass gfp param into aa_policy_init()
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:27 -08:00
John Johansen 92b6d8eff5 apparmor: allow ns visibility question to consider subnses
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:22 -08:00
John Johansen 31617ddfdd apparmor: add fn to lookup profiles by fqname
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:22 -08:00
John Johansen 9a2d40c12d apparmor: add strn version of aa_find_ns
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:20 -08:00
John Johansen 8399588a7f apparmor: rename replacedby to proxy
Proxy is shorter and a better fit than replaceby, so rename it.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:19 -08:00
John Johansen 98849dff90 apparmor: rename namespace to ns to improve code line lengths
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 00:42:16 -08:00
John Johansen cff281f686 apparmor: split apparmor policy namespaces code into its own file
Policy namespaces will be diverging from profile management and
expanding so put it in its own file.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 00:42:15 -08:00