Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760119Ab3CHS7N (ORCPT ); Fri, 8 Mar 2013 13:59:13 -0500 Received: from mail-vc0-f176.google.com ([209.85.220.176]:49603 "EHLO mail-vc0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751783Ab3CHS7M (ORCPT ); Fri, 8 Mar 2013 13:59:12 -0500 MIME-Version: 1.0 In-Reply-To: References: Date: Fri, 8 Mar 2013 20:59:11 +0200 Message-ID: Subject: Re: snd_seq_timer_open() NULL pointer dereference From: Tommi Rantala To: Takashi Iwai Cc: Jaroslav Kysela , alsa-devel@alsa-project.org, LKML , Dave Jones Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1949 Lines: 61 2013/3/8 Takashi Iwai : > At Thu, 7 Mar 2013 21:59:32 +0200, > Tommi Rantala wrote: >> >> Hello, >> >> I'm hitting this while fuzzing the kernel with Trinity: > > The patch below fixes a clear bug in the code path. > Could you check whether it'll fit? > > > thanks, > > Takashi > > --- > From: Takashi Iwai > Subject: [PATCH] ALSA: seq: Fix missing error handling in snd_seq_timer_open() > > snd_seq_timer_open() didn't catch the whole error path but let through > if the timer id is a slave. This may lead to Oops by accessing the > uninitialized pointer. > > Signed-off-by: Takashi Iwai Confirmed, this fixes the bug. Thanks! Reported-and-tested-by: Tommi Rantala > --- > sound/core/seq/seq_timer.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/sound/core/seq/seq_timer.c b/sound/core/seq/seq_timer.c > index 160b1bd..24d44b2 100644 > --- a/sound/core/seq/seq_timer.c > +++ b/sound/core/seq/seq_timer.c > @@ -290,10 +290,10 @@ int snd_seq_timer_open(struct snd_seq_queue *q) > tid.device = SNDRV_TIMER_GLOBAL_SYSTEM; > err = snd_timer_open(&t, str, &tid, q->queue); > } > - if (err < 0) { > - snd_printk(KERN_ERR "seq fatal error: cannot create timer (%i)\n", err); > - return err; > - } > + } > + if (err < 0) { > + snd_printk(KERN_ERR "seq fatal error: cannot create timer (%i)\n", err); > + return err; > } > t->callback = snd_seq_timer_interrupt; > t->callback_data = q; > -- > 1.8.1.4 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/