From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161748AbcA0VR5 (ORCPT ); Wed, 27 Jan 2016 16:17:57 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:43350 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161202AbcA0UjI (ORCPT ); Wed, 27 Jan 2016 15:39:08 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Takashi Iwai , Kamal Mostafa Subject: [PATCH 4.2.y-ckt 166/268] ALSA: control: Avoid kernel warnings from tlv ioctl with numid 0 Date: Wed, 27 Jan 2016 12:33:47 -0800 Message-Id: <1453926929-17663-167-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1453926929-17663-1-git-send-email-kamal@canonical.com> References: <1453926929-17663-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 4.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.2.8-ckt3 -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: Kamal Mostafa --- sound/core/control.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/sound/core/control.c b/sound/core/control.c index 196a6fe..a85d455 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -1405,6 +1405,8 @@ 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) { -- 1.9.1