diff options
| author | Fabian Frederick <fabf@skynet.be> | 2016-08-02 14:03:07 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-08-02 17:31:41 -0400 |
| commit | 9b24fef9f0410fb5364245d6cc2bd044cc064007 (patch) | |
| tree | 21bf1cc4aeec71d03c7a7ffa7c98435b3acf719d /ipc/msg.c | |
| parent | b5afba2974f9ebbaaa11b5a633e55db9be3cc363 (diff) | |
| download | lwn-9b24fef9f0410fb5364245d6cc2bd044cc064007.tar.gz lwn-9b24fef9f0410fb5364245d6cc2bd044cc064007.zip | |
sysv, ipc: fix security-layer leaking
Commit 53dad6d3a8e5 ("ipc: fix race with LSMs") updated ipc_rcu_putref()
to receive rcu freeing function but used generic ipc_rcu_free() instead
of msg_rcu_free() which does security cleaning.
Running LTP msgsnd06 with kmemleak gives the following:
cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff88003c0a11f8 (size 8):
comm "msgsnd06", pid 1645, jiffies 4294672526 (age 6.549s)
hex dump (first 8 bytes):
1b 00 00 00 01 00 00 00 ........
backtrace:
kmemleak_alloc+0x23/0x40
kmem_cache_alloc_trace+0xe1/0x180
selinux_msg_queue_alloc_security+0x3f/0xd0
security_msg_queue_alloc+0x2e/0x40
newque+0x4e/0x150
ipcget+0x159/0x1b0
SyS_msgget+0x39/0x40
entry_SYSCALL_64_fastpath+0x13/0x8f
Manfred Spraul suggested to fix sem.c as well and Davidlohr Bueso to
only use ipc_rcu_free in case of security allocation failure in newary()
Fixes: 53dad6d3a8e ("ipc: fix race with LSMs")
Link: http://lkml.kernel.org/r/1470083552-22966-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@vger.kernel.org> [3.12+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'ipc/msg.c')
| -rw-r--r-- | ipc/msg.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/ipc/msg.c b/ipc/msg.c index 1471db9a7e61..c6521c205cb4 100644 --- a/ipc/msg.c +++ b/ipc/msg.c @@ -680,7 +680,7 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, rcu_read_lock(); ipc_lock_object(&msq->q_perm); - ipc_rcu_putref(msq, ipc_rcu_free); + ipc_rcu_putref(msq, msg_rcu_free); /* raced with RMID? */ if (!ipc_valid_object(&msq->q_perm)) { err = -EIDRM; |