From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932298Ab3FEUyt (ORCPT ); Wed, 5 Jun 2013 16:54:49 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36356 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932235Ab3FEUxe (ORCPT ); Wed, 5 Jun 2013 16:53:34 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xi Wang , Takashi Iwai , Ben Hutchings Subject: [ 31/33] ALSA: usb-audio: avoid integer overflow in create_fixed_stream_quirk() Date: Wed, 5 Jun 2013 13:53:09 -0700 Message-Id: <20130605204709.548278568@linuxfoundation.org> X-Mailer: git-send-email 1.8.3.rc0.20.gb99dd2e In-Reply-To: <20130605204702.359510786@linuxfoundation.org> References: <20130605204702.359510786@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xi Wang commit 8866f405efd4171f9d9c91901d2dd02f01bacb60 upstream. A malicious USB device could feed in a large nr_rates value. This would cause the subsequent call to kmemdup() to allocate a smaller buffer than expected, leading to out-of-bounds access. This patch validates the nr_rates value and reuses the limit introduced in commit 4fa0e81b ("ALSA: usb-audio: fix possible hang and overflow in parse_uac2_sample_rate_range()"). Signed-off-by: Xi Wang Signed-off-by: Takashi Iwai Cc: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- sound/usb/card.h | 1 + sound/usb/format.c | 4 +--- sound/usb/quirks.c | 6 +++++- 3 files changed, 7 insertions(+), 4 deletions(-) --- a/sound/usb/card.h +++ b/sound/usb/card.h @@ -1,6 +1,7 @@ #ifndef __USBAUDIO_CARD_H #define __USBAUDIO_CARD_H +#define MAX_NR_RATES 1024 #define MAX_PACKS 20 #define MAX_PACKS_HS (MAX_PACKS * 8) /* in high speed mode */ #define MAX_URBS 8 --- a/sound/usb/format.c +++ b/sound/usb/format.c @@ -209,8 +209,6 @@ static int parse_audio_format_rates_v1(s return 0; } -#define MAX_UAC2_NR_RATES 1024 - /* * Helper function to walk the array of sample rate triplets reported by * the device. The problem is that we need to parse whole array first to @@ -255,7 +253,7 @@ static int parse_uac2_sample_rate_range( fp->rates |= snd_pcm_rate_to_rate_bit(rate); nr_rates++; - if (nr_rates >= MAX_UAC2_NR_RATES) { + if (nr_rates >= MAX_NR_RATES) { snd_printk(KERN_ERR "invalid uac2 rates\n"); break; } --- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -131,10 +131,14 @@ static int create_fixed_stream_quirk(str unsigned *rate_table = NULL; fp = kmemdup(quirk->data, sizeof(*fp), GFP_KERNEL); - if (! fp) { + if (!fp) { snd_printk(KERN_ERR "cannot memdup\n"); return -ENOMEM; } + if (fp->nr_rates > MAX_NR_RATES) { + kfree(fp); + return -EINVAL; + } if (fp->nr_rates > 0) { rate_table = kmalloc(sizeof(int) * fp->nr_rates, GFP_KERNEL); if (!rate_table) {