From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:59775 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965685AbcA0Tt3 (ORCPT ); Wed, 27 Jan 2016 14:49:29 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Vyukov , Takashi Iwai Subject: [PATCH 3.10 23/53] ALSA: control: Avoid kernel warnings from tlv ioctl with numid 0 Date: Wed, 27 Jan 2016 10:15:42 -0800 Message-Id: <20160127180650.178222511@linuxfoundation.org> In-Reply-To: <20160127180648.932559859@linuxfoundation.org> References: <20160127180648.932559859@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: stable-owner@vger.kernel.org List-ID: 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ 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: Greg Kroah-Hartman --- sound/core/control.c | 2 ++ 1 file changed, 2 insertions(+) --- a/sound/core/control.c +++ b/sound/core/control.c @@ -1325,6 +1325,8 @@ static int snd_ctl_tlv_ioctl(struct snd_ 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) {