This is a note to let you know that I've just added the patch titled
ALSA: usb-audio: Add sanity checks to FE parser
to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
alsa-usb-audio-add-sanity-checks-to-fe-parser.patch
and it can be found in the queue-3.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From d937cd6790a2bef2d07b500487646bd794c039bb Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@xxxxxxx>
Date: Tue, 21 Nov 2017 16:55:51 +0100
Subject: ALSA: usb-audio: Add sanity checks to FE parser
From: Takashi Iwai <tiwai@xxxxxxx>
commit d937cd6790a2bef2d07b500487646bd794c039bb upstream.
When the usb-audio descriptor contains the malformed feature unit
description with a too short length, the driver may access
out-of-bounds. Add a sanity check of the header size at the beginning
of parse_audio_feature_unit().
Fixes: 23caaf19b11e ("ALSA: usb-mixer: Add support for Audio Class v2.0")
Reported-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
sound/usb/mixer.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -1373,6 +1373,12 @@ static int parse_audio_feature_unit(stru
__u8 *bmaControls;
if (state->mixer->protocol == UAC_VERSION_1) {
+ if (hdr->bLength < 7) {
+ usb_audio_err(state->chip,
+ "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
+ unitid);
+ return -EINVAL;
+ }
csize = hdr->bControlSize;
if (!csize) {
usb_audio_dbg(state->chip,
@@ -1390,6 +1396,12 @@ static int parse_audio_feature_unit(stru
}
} else {
struct uac2_feature_unit_descriptor *ftr = _ftr;
+ if (hdr->bLength < 6) {
+ usb_audio_err(state->chip,
+ "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
+ unitid);
+ return -EINVAL;
+ }
csize = 4;
channels = (hdr->bLength - 6) / 4 - 1;
bmaControls = ftr->bmaControls;
Patches currently in stable-queue which might be from tiwai@xxxxxxx are
queue-3.18/alsa-usb-audio-fix-potential-zero-division-at-parsing-fu.patch
queue-3.18/alsa-timer-remove-kernel-warning-at-compat-ioctl-error-paths.patch
queue-3.18/alsa-hda-add-raven-pci-id.patch
queue-3.18/alsa-usb-audio-add-sanity-checks-in-v2-clock-parsers.patch
queue-3.18/alsa-usb-audio-fix-potential-out-of-bound-access-at-parsing-su.patch
queue-3.18/alsa-usb-audio-add-sanity-checks-to-fe-parser.patch