From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934120AbcBCWhn (ORCPT ); Wed, 3 Feb 2016 17:37:43 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:47086 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757579AbcBCWhX (ORCPT ); Wed, 3 Feb 2016 17:37:23 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Takashi Iwai , Luis Henriques Subject: [PATCH 3.16.y-ckt 129/180] ALSA: control: Avoid kernel warnings from tlv ioctl with numid 0 Date: Wed, 3 Feb 2016 22:32:15 +0000 Message-Id: <1454538786-12215-130-git-send-email-luis.henriques@canonical.com> In-Reply-To: <1454538786-12215-1-git-send-email-luis.henriques@canonical.com> References: <1454538786-12215-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt24 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Takashi Iwai commit c0bcdbdff3ff73a54161fca3cb8b6cdbd0bb8762 upstream. When a TLV ioctl with numid zero is handled, the driver may spew a kernel warning with a stack trace at each call. The check was intended obviously only for a kernel driver, but not for a user interaction. Let's fix it. This was spotted by syzkaller fuzzer. Reported-by: Dmitry Vyukov Signed-off-by: Takashi Iwai Signed-off-by: Luis Henriques --- sound/core/control.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/sound/core/control.c b/sound/core/control.c index 8cdf0a4b327b..1d395d865f1b 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -1324,6 +1324,8 @@ static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file, return -EFAULT; if (tlv.length < sizeof(unsigned int) * 2) return -EINVAL; + if (!tlv.numid) + return -EINVAL; down_read(&card->controls_rwsem); kctl = snd_ctl_find_numid(card, tlv.numid); if (kctl == NULL) {