From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759951AbcCDQKW (ORCPT ); Fri, 4 Mar 2016 11:10:22 -0500 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:60663 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759064AbcCDQDN (ORCPT ); Fri, 4 Mar 2016 11:03:13 -0500 Message-Id: <20160304153002.724265828@1wt.eu> User-Agent: quilt/0.63-1 Date: Fri, 04 Mar 2016 16:30:46 +0100 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Dmitry Vyukov , Takashi Iwai , Ben Hutchings , Willy Tarreau Subject: [PATCH 2.6.32 46/55] ALSA: timer: Fix double unlink of active_list MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 In-Reply-To: <148ee355b419e9976ca727513a1405c8@local> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Takashi Iwai commit ee8413b01045c74340aa13ad5bdf905de32be736 upstream. ALSA timer instance object has a couple of linked lists and they are unlinked unconditionally at snd_timer_stop(). Meanwhile snd_timer_interrupt() unlinks it, but it calls list_del() which leaves the element list itself unchanged. This ends up with unlinking twice, and it was caught by syzkaller fuzzer. The fix is to use list_del_init() variant properly there, too. Reported-by: Dmitry Vyukov Tested-by: Dmitry Vyukov Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings Signed-off-by: Willy Tarreau --- sound/core/timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/core/timer.c b/sound/core/timer.c index 21f5df6..fb29803 100644 --- a/sound/core/timer.c +++ b/sound/core/timer.c @@ -724,7 +724,7 @@ void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left) } else { ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING; if (--timer->running) - list_del(&ti->active_list); + list_del_init(&ti->active_list); } if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) || (ti->flags & SNDRV_TIMER_IFLG_FAST)) -- 1.7.12.2.21.g234cd45.dirty