diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2017-03-04 10:27:19 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2017-03-14 21:45:36 +0100 |
| commit | 9bbb25afeb182502ca4f2c4f3f88af0681b34cae (patch) | |
| tree | dc5b892ea7ce2ac927eb9ed39d97012bfedd7d23 | |
| parent | futex: Fix potential use-after-free in FUTEX_REQUEUE_PI (diff) | |
| download | linux-9bbb25afeb182502ca4f2c4f3f88af0681b34cae.tar.xz linux-9bbb25afeb182502ca4f2c4f3f88af0681b34cae.zip | |
futex: Add missing error handling to FUTEX_REQUEUE_PI
Thomas spotted that fixup_pi_state_owner() can return errors and we
fail to unlock the rt_mutex in that case.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: xlpang@redhat.com
Cc: rostedt@goodmis.org
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: dvhart@infradead.org
Cc: bristot@redhat.com
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170304093558.867401760@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | kernel/futex.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/futex.c b/kernel/futex.c index 3a4775fd7468..45858ec73941 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2898,6 +2898,8 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags, if (q.pi_state && (q.pi_state->owner != current)) { spin_lock(q.lock_ptr); ret = fixup_pi_state_owner(uaddr2, &q, current); + if (ret && rt_mutex_owner(&q.pi_state->pi_mutex) == current) + rt_mutex_unlock(&q.pi_state->pi_mutex); /* * Drop the reference to the pi state which * the requeue_pi() code acquired for us. |