[GIT] Apparmor bugfixes for 3.12

From: James Morris
Date: Tue Oct 15 2013 - 21:32:01 EST

A couple more regressions fixed, please pull.

The following changes since commit 34ec4de42be5006abdd8d0c08b306ffaa64d0d5d:

Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux (2013-10-15 17:14:13 -0700)

are available in the git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security.git for-linus

John Johansen (2):
apparmor: fix memleak of the profile hash
apparmor: fix bad lock balance when introspecting policy

security/apparmor/apparmorfs.c | 4 +---
security/apparmor/policy.c | 1 +
2 files changed, 2 insertions(+), 3 deletions(-)

---

commit ed2c7da3a40c58410508fe24e12d03e508d7ec01
Author: John Johansen <john.johansen@xxxxxxxxxxxxx>
Date: Mon Oct 14 11:46:27 2013 -0700

apparmor: fix bad lock balance when introspecting policy

BugLink: http://bugs.launchpad.net/bugs/1235977

The profile introspection seq file has a locking bug when policy is viewed
from a virtual root (task in a policy namespace), introspection from the
real root is not affected.

The test for root
while (parent) {
is correct for the real root, but incorrect for tasks in a policy namespace.
This allows the task to walk backup the policy tree past its virtual root
causing it to be unlocked before the virtual root should be in the p_stop
fn.

This results in the following lockdep back trace:
[ 78.479744] [ BUG: bad unlock balance detected! ]
[ 78.479792] 3.11.0-11-generic #17 Not tainted
[ 78.479838] -------------------------------------
[ 78.479885] grep/2223 is trying to release lock (&ns->lock) at:
[ 78.479952] [<ffffffff817bf3be>] mutex_unlock+0xe/0x10
[ 78.480002] but there are no more locks to release!
[ 78.480037]
[ 78.480037] other info that might help us debug this:
[ 78.480037] 1 lock held by grep/2223:
[ 78.480037] #0: (&p->lock){+.+.+.}, at: [<ffffffff812111bd>] seq_read+0x3d/0x3d0
[ 78.480037]
[ 78.480037] stack backtrace:
[ 78.480037] CPU: 0 PID: 2223 Comm: grep Not tainted 3.11.0-11-generic #17
[ 78.480037] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 78.480037] ffffffff817bf3be ffff880007763d60 ffffffff817b97ef ffff8800189d2190
[ 78.480037] ffff880007763d88 ffffffff810e1c6e ffff88001f044730 ffff8800189d2190
[ 78.480037] ffffffff817bf3be ffff880007763e00 ffffffff810e5bd6 0000000724fe56b7
[ 78.480037] Call Trace:
[ 78.480037] [<ffffffff817bf3be>] ? mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff817b97ef>] dump_stack+0x54/0x74
[ 78.480037] [<ffffffff810e1c6e>] print_unlock_imbalance_bug+0xee/0x100
[ 78.480037] [<ffffffff817bf3be>] ? mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff810e5bd6>] lock_release_non_nested+0x226/0x300
[ 78.480037] [<ffffffff817bf2fe>] ? __mutex_unlock_slowpath+0xce/0x180
[ 78.480037] [<ffffffff817bf3be>] ? mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff810e5d5c>] lock_release+0xac/0x310
[ 78.480037] [<ffffffff817bf2b3>] __mutex_unlock_slowpath+0x83/0x180
[ 78.480037] [<ffffffff817bf3be>] mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff81376c91>] p_stop+0x51/0x90
[ 78.480037] [<ffffffff81211408>] seq_read+0x288/0x3d0
[ 78.480037] [<ffffffff811e9d9e>] vfs_read+0x9e/0x170
[ 78.480037] [<ffffffff811ea8cc>] SyS_read+0x4c/0xa0
[ 78.480037] [<ffffffff817ccc9d>] system_call_fastpath+0x1a/0x1f

Signed-off-by: John Johansen <john.johansen@xxxxxxxxxxxxx>
Signed-off-by: James Morris <james.l.morris@xxxxxxxxxx>

diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c
index 95c2b26..7db9954 100644
--- a/security/apparmor/apparmorfs.c
+++ b/security/apparmor/apparmorfs.c
@@ -580,15 +580,13 @@ static struct aa_namespace *__next_namespace(struct aa_namespace *root,

/* check if the next ns is a sibling, parent, gp, .. */
parent = ns->parent;
- while (parent) {
+ while (ns != root) {
mutex_unlock(&ns->lock);
next = list_entry_next(ns, base.list);
if (!list_entry_is_head(next, &parent->sub_ns, base.list)) {
mutex_lock(&next->lock);
return next;
}
- if (parent == root)
- return NULL;
ns = parent;
parent = parent->parent;
}

commit 5cb3e91ebd0405519795f243adbfc4ed2a6fe53f
Author: John Johansen <john.johansen@xxxxxxxxxxxxx>
Date: Mon Oct 14 11:44:34 2013 -0700

apparmor: fix memleak of the profile hash

BugLink: http://bugs.launchpad.net/bugs/1235523

This fixes the following kmemleak trace:
unreferenced object 0xffff8801e8c35680 (size 32):
comm "apparmor_parser", pid 691, jiffies 4294895667 (age 13230.876s)
hex dump (first 32 bytes):
e0 d3 4e b5 ac 6d f4 ed 3f cb ee 48 1c fd 40 cf ..N..m..?..H..@.
5b cc e9 93 00 00 00 00 00 00 00 00 00 00 00 00 [...............
backtrace:
[<ffffffff817a97ee>] kmemleak_alloc+0x4e/0xb0
[<ffffffff811ca9f3>] __kmalloc+0x103/0x290
[<ffffffff8138acbc>] aa_calc_profile_hash+0x6c/0x150
[<ffffffff8138074d>] aa_unpack+0x39d/0xd50
[<ffffffff8137eced>] aa_replace_profiles+0x3d/0xd80
[<ffffffff81376937>] profile_replace+0x37/0x50
[<ffffffff811e9f2d>] vfs_write+0xbd/0x1e0
[<ffffffff811ea96c>] SyS_write+0x4c/0xa0
[<ffffffff817ccb1d>] system_call_fastpath+0x1a/0x1f
[<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: John Johansen <john.johansen@xxxxxxxxxxxxx>
Signed-off-by: James Morris <james.l.morris@xxxxxxxxxx>

diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c
index 345bec0..705c287 100644
--- a/security/apparmor/policy.c
+++ b/security/apparmor/policy.c
@@ -610,6 +610,7 @@ void aa_free_profile(struct aa_profile *profile)
aa_put_dfa(profile->policy.dfa);
aa_put_replacedby(profile->replacedby);

+ kzfree(profile->hash);
kzfree(profile);
}

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