Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752262AbdGPOhU (ORCPT ); Sun, 16 Jul 2017 10:37:20 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:44258 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752884AbdGPOOQ (ORCPT ); Sun, 16 Jul 2017 10:14:16 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, bigeasy@linutronix.de, rostedt@goodmis.org, mathieu.desnoyers@efficios.com, bristot@redhat.com, "Peter Zijlstra" , dvhart@infradead.org, jdesfossez@efficios.com, xlpang@redhat.com, juri.lelli@arm.com, "Darren Hart" , "Thomas Gleixner" Date: Sun, 16 Jul 2017 14:56:46 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 048/178] futex: Add missing error handling to FUTEX_REQUEUE_PI In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1365 Lines: 40 3.16.46-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Peter Zijlstra 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 Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Darren Hart 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 Signed-off-by: Ben Hutchings --- kernel/futex.c | 2 ++ 1 file changed, 2 insertions(+) --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2661,6 +2661,8 @@ static int futex_wait_requeue_pi(u32 __u 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.