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>
This commit is contained in:
Peter Zijlstra 2017-03-04 10:27:19 +01:00 committed by Thomas Gleixner
parent c236c8e95a
commit 9bbb25afeb

View File

@ -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)) { if (q.pi_state && (q.pi_state->owner != current)) {
spin_lock(q.lock_ptr); spin_lock(q.lock_ptr);
ret = fixup_pi_state_owner(uaddr2, &q, current); 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 * Drop the reference to the pi state which
* the requeue_pi() code acquired for us. * the requeue_pi() code acquired for us.