| From | Jiri Slaby <> | Subject | [PATCH 3.12 038/142] futex: Add missing error handling to FUTEX_REQUEUE_PI | Date | Mon, 10 Apr 2017 17:31:59 +0200 |
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From: Peter Zijlstra <peterz@infradead.org>
3.12-stable review patch. If anyone has any objections, please let me know.
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commit 9bbb25afeb182502ca4f2c4f3f88af0681b34cae upstream.
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 Link: http://lkml.kernel.org/r/20170304093558.867401760@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jiri Slaby <jslaby@suse.cz> --- kernel/futex.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/kernel/futex.c b/kernel/futex.c index 9667d9233289..566e2e0e56cf 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2496,6 +2496,8 @@ 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. -- 2.12.2
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