Commit Graph

150 Commits

Author SHA1 Message Date
John Johansen
4cd4fc7703 apparmor: fix suspicious RCU usage warning in policy.c/policy.h
The recent 3.12 pull request for apparmor was missing a couple rcu _protected
access modifiers. Resulting in the follow suspicious RCU usage

 [   29.804534] [ INFO: suspicious RCU usage. ]
 [   29.804539] 3.11.0+ #5 Not tainted
 [   29.804541] -------------------------------
 [   29.804545] security/apparmor/include/policy.h:363 suspicious rcu_dereference_check() usage!
 [   29.804548]
 [   29.804548] other info that might help us debug this:
 [   29.804548]
 [   29.804553]
 [   29.804553] rcu_scheduler_active = 1, debug_locks = 1
 [   29.804558] 2 locks held by apparmor_parser/1268:
 [   29.804560]  #0:  (sb_writers#9){.+.+.+}, at: [<ffffffff81120a4c>] file_start_write+0x27/0x29
 [   29.804576]  #1:  (&ns->lock){+.+.+.}, at: [<ffffffff811f5d88>] aa_replace_profiles+0x166/0x57c
 [   29.804589]
 [   29.804589] stack backtrace:
 [   29.804595] CPU: 0 PID: 1268 Comm: apparmor_parser Not tainted 3.11.0+ #5
 [   29.804599] Hardware name: ASUSTeK Computer Inc.         UL50VT          /UL50VT    , BIOS 217     03/01/2010
 [   29.804602]  0000000000000000 ffff8800b95a1d90 ffffffff8144eb9b ffff8800b94db540
 [   29.804611]  ffff8800b95a1dc0 ffffffff81087439 ffff880138cc3a18 ffff880138cc3a18
 [   29.804619]  ffff8800b9464a90 ffff880138cc3a38 ffff8800b95a1df0 ffffffff811f5084
 [   29.804628] Call Trace:
 [   29.804636]  [<ffffffff8144eb9b>] dump_stack+0x4e/0x82
 [   29.804642]  [<ffffffff81087439>] lockdep_rcu_suspicious+0xfc/0x105
 [   29.804649]  [<ffffffff811f5084>] __aa_update_replacedby+0x53/0x7f
 [   29.804655]  [<ffffffff811f5408>] __replace_profile+0x11f/0x1ed
 [   29.804661]  [<ffffffff811f6032>] aa_replace_profiles+0x410/0x57c
 [   29.804668]  [<ffffffff811f16d4>] profile_replace+0x35/0x4c
 [   29.804674]  [<ffffffff81120fa3>] vfs_write+0xad/0x113
 [   29.804680]  [<ffffffff81121609>] SyS_write+0x44/0x7a
 [   29.804687]  [<ffffffff8145bfd2>] system_call_fastpath+0x16/0x1b
 [   29.804691]
 [   29.804694] ===============================
 [   29.804697] [ INFO: suspicious RCU usage. ]
 [   29.804700] 3.11.0+ #5 Not tainted
 [   29.804703] -------------------------------
 [   29.804706] security/apparmor/policy.c:566 suspicious rcu_dereference_check() usage!
 [   29.804709]
 [   29.804709] other info that might help us debug this:
 [   29.804709]
 [   29.804714]
 [   29.804714] rcu_scheduler_active = 1, debug_locks = 1
 [   29.804718] 2 locks held by apparmor_parser/1268:
 [   29.804721]  #0:  (sb_writers#9){.+.+.+}, at: [<ffffffff81120a4c>] file_start_write+0x27/0x29
 [   29.804733]  #1:  (&ns->lock){+.+.+.}, at: [<ffffffff811f5d88>] aa_replace_profiles+0x166/0x57c
 [   29.804744]
 [   29.804744] stack backtrace:
 [   29.804750] CPU: 0 PID: 1268 Comm: apparmor_parser Not tainted 3.11.0+ #5
 [   29.804753] Hardware name: ASUSTeK Computer Inc.         UL50VT          /UL50VT    , BIOS 217     03/01/2010
 [   29.804756]  0000000000000000 ffff8800b95a1d80 ffffffff8144eb9b ffff8800b94db540
 [   29.804764]  ffff8800b95a1db0 ffffffff81087439 ffff8800b95b02b0 0000000000000000
 [   29.804772]  ffff8800b9efba08 ffff880138cc3a38 ffff8800b95a1dd0 ffffffff811f4f94
 [   29.804779] Call Trace:
 [   29.804786]  [<ffffffff8144eb9b>] dump_stack+0x4e/0x82
 [   29.804791]  [<ffffffff81087439>] lockdep_rcu_suspicious+0xfc/0x105
 [   29.804798]  [<ffffffff811f4f94>] aa_free_replacedby_kref+0x4d/0x62
 [   29.804804]  [<ffffffff811f4f47>] ? aa_put_namespace+0x17/0x17
 [   29.804810]  [<ffffffff811f4f0b>] kref_put+0x36/0x40
 [   29.804816]  [<ffffffff811f5423>] __replace_profile+0x13a/0x1ed
 [   29.804822]  [<ffffffff811f6032>] aa_replace_profiles+0x410/0x57c
 [   29.804829]  [<ffffffff811f16d4>] profile_replace+0x35/0x4c
 [   29.804835]  [<ffffffff81120fa3>] vfs_write+0xad/0x113
 [   29.804840]  [<ffffffff81121609>] SyS_write+0x44/0x7a
 [   29.804847]  [<ffffffff8145bfd2>] system_call_fastpath+0x16/0x1b

Reported-by: miles.lane@gmail.com
CC: paulmck@linux.vnet.ibm.com
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-09-30 09:54:01 +10:00
Tyler Hicks
71ac7f6255 apparmor: Use shash crypto API interface for profile hashes
Use the shash interface, rather than the hash interface, when hashing
AppArmor profiles. The shash interface does not use scatterlists and it
is a better fit for what AppArmor needs.

This fixes a kernel paging BUG when aa_calc_profile_hash() is passed a
buffer from vmalloc(). The hash interface requires callers to handle
vmalloc() buffers differently than what AppArmor was doing. Due to
vmalloc() memory not being physically contiguous, each individual page
behind the buffer must be assigned to a scatterlist with sg_set_page()
and then the scatterlist passed to crypto_hash_update().

The shash interface does not have that limitation and allows vmalloc()
and kmalloc() buffers to be handled in the same manner.

BugLink: https://launchpad.net/bugs/1216294/
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=62261

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-09-30 09:53:59 +10:00
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
Steven Rostedt
5265fc6219 module/lsm: Have apparmor module parameters work with no args
The apparmor module parameters for param_ops_aabool and
param_ops_aalockpolicy are both based off of the param_ops_bool,
and can handle a NULL value passed in as val. Have it enable the
new KERNEL_PARAM_FL_NOARGS flag to allow the parameters to be set
without having to state "=y" or "=1".

Cc: John Johansen <john.johansen@canonical.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-08-20 15:37:44 +09:30
John Johansen
f8eb8a1324 apparmor: add the ability to report a sha1 hash of loaded policy
Provide userspace the ability to introspect a sha1 hash value for each
profile currently loaded.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2013-08-14 11:42:08 -07:00
John Johansen
84f1f78742 apparmor: export set of capabilities supported by the apparmor module
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2013-08-14 11:42:07 -07:00
John Johansen
29b3822f1e apparmor: add the profile introspection file to interface
Add the dynamic namespace relative profiles file to the interace, to allow
introspection of loaded profiles and their modes.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
2013-08-14 11:42:07 -07:00
John Johansen
556d0be74b apparmor: add an optional profile attachment string for profiles
Add the ability to take in and report a human readable profile attachment
string for profiles so that attachment specifications can be easily
inspected.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2013-08-14 11:42:07 -07:00
John Johansen
0d259f043f apparmor: add interface files for profiles and namespaces
Add basic interface files to access namespace and profile information.
The interface files are created when a profile is loaded and removed
when the profile or namespace is removed.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-08-14 11:42:07 -07:00
John Johansen
038165070a apparmor: allow setting any profile into the unconfined state
Allow emulating the default profile behavior from boot, by allowing
loading of a profile in the unconfined state into a new NS.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2013-08-14 11:42:07 -07:00
John Johansen
8651e1d657 apparmor: make free_profile available outside of policy.c
Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-08-14 11:42:06 -07:00
John Johansen
742058b0f3 apparmor: rework namespace free path
namespaces now completely use the unconfined profile to track the
refcount and rcu freeing cycle. So rework the code to simplify (track
everything through the profile path right up to the end), and move the
rcu_head from policy base to profile as the namespace no longer needs
it.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2013-08-14 11:42:06 -07:00
John Johansen
fa2ac468db apparmor: update how unconfined is handled
ns->unconfined is being used read side without locking, nor rcu but is
being updated when a namespace is removed. This works for the root ns
which is never removed but has a race window and can cause failures when
children namespaces are removed.

Also ns and ns->unconfined have a circular refcounting dependency that
is problematic and must be broken. Currently this is done incorrectly
when the namespace is destroyed.

Fix this by forward referencing unconfined via the replacedby infrastructure
instead of directly updating the ns->unconfined pointer.

Remove the circular refcount dependency by making the ns and its unconfined
profile share the same refcount.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2013-08-14 11:42:06 -07:00
John Johansen
77b071b340 apparmor: change how profile replacement update is done
remove the use of replaced by chaining and move to profile invalidation
and lookup to handle task replacement.

Replacement chaining can result in large chains of profiles being pinned
in memory when one profile in the chain is use. With implicit labeling
this will be even more of a problem, so move to a direct lookup method.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-08-14 11:42:06 -07:00
John Johansen
01e2b670aa apparmor: convert profile lists to RCU based locking
Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-08-14 11:42:06 -07:00
John Johansen
dd51c84857 apparmor: provide base for multiple profiles to be replaced at once
previously profiles had to be loaded one at a time, which could result
in cases where a replacement of a set would partially succeed, and then fail
resulting in inconsistent policy.

Allow multiple profiles to replaced "atomically" so that the replacement
either succeeds or fails for the entire set of profiles.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-08-14 11:42:06 -07:00
John Johansen
9d910a3bc0 apparmor: add a features/policy dir to interface
Add a policy directory to features to contain features that can affect
policy compilation but do not affect mediation. Eg of such features would
be types of dfa compression supported, etc.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
2013-08-14 11:42:05 -07:00
John Johansen
c611616cd3 apparmor: enable users to query whether apparmor is enabled
Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-08-14 11:42:05 -07:00
Tetsuo Handa
dfe4ac28be apparmor: remove minimum size check for vmalloc()
This is a follow-up to commit b5b3ee6c "apparmor: no need to delay vfree()".

Since vmalloc() will do "size = PAGE_ALIGN(size);",
we don't need to check for "size >= sizeof(struct work_struct)".

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-08-14 11:42:05 -07:00
Al Viro
b5b3ee6c9c apparmor: no need to delay vfree()
vfree() can be called from interrupt contexts now

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-05-12 21:31:02 +10:00
John Johansen
2654bfbc2b apparmor: fix fully qualified name parsing
currently apparmor name parsing is only correctly handling
:<NS>:<profile>

but
:<NS>://<profile>

is also a valid form and what is exported to userspace.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-04-28 00:39:37 -07:00
John Johansen
3eea57c26e apparmor: fix setprocattr arg processing for onexec
the exec file isn't processing its command arg. It should only set be
responding to a command of exec.

Also cleanup setprocattr some more while we are at it.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-04-28 00:39:36 -07:00
John Johansen
214beacaa7 apparmor: localize getting the security context to a few macros
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2013-04-28 00:39:35 -07:00
John Johansen
53fe8b9961 apparmor: fix sparse warnings
Fix a couple of warning reported by sparse

Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-04-28 00:39:35 -07:00
John Johansen
41d1b3e868 apparmor: Fix smatch warning in aa_remove_profiles
smatch reports
  error: potential NULL dereference 'ns'.

this can not actually occur because it relies on aa_split_fqname setting
both ns_name and name as null but ns_name will actually always have a
value in this case.

so remove the unnecessary if (ns_name) conditional that is resulting
in the false positive further down.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-04-28 00:39:34 -07:00