Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759566AbcDBBlc (ORCPT ); Fri, 1 Apr 2016 21:41:32 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:53819 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755935AbcDBAyp (ORCPT ); Fri, 1 Apr 2016 20:54:45 -0400 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 3.19.y-ckt 013/170] ALSA: usb-audio: Fix NULL dereference in create_fixed_stream_quirk() Date: Fri, 1 Apr 2016 17:51:39 -0700 Message-Id: <1459558456-24452-14-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1459558456-24452-1-git-send-email-kamal@canonical.com> References: <1459558456-24452-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1208 Lines: 41 3.19.8-ckt18 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Takashi Iwai commit 0f886ca12765d20124bd06291c82951fd49a33be upstream. create_fixed_stream_quirk() may cause a NULL-pointer dereference by accessing the non-existing endpoint when a USB device with a malformed USB descriptor is used. This patch avoids it simply by adding a sanity check of bNumEndpoints before the accesses. Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=971125 Signed-off-by: Takashi Iwai Signed-off-by: Kamal Mostafa --- sound/usb/quirks.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c index fb9c394..20ed435 100644 --- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -177,6 +177,12 @@ static int create_fixed_stream_quirk(struct snd_usb_audio *chip, } alts = &iface->altsetting[fp->altset_idx]; altsd = get_iface_desc(alts); + if (altsd->bNumEndpoints < 1) { + kfree(fp); + kfree(rate_table); + return -EINVAL; + } + fp->protocol = altsd->bInterfaceProtocol; if (fp->datainterval == 0) -- 2.7.4