This is a note to let you know that I've just added the patch titled
ALSA: usb-audio: Fix potential zero-division at parsing FU
to the 4.9-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-fix-potential-zero-division-at-parsing-fu.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 8428a8ebde2db1e988e41a58497a28beb7ce1705 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@xxxxxxx>
Date: Tue, 21 Nov 2017 17:07:43 +0100
Subject: ALSA: usb-audio: Fix potential zero-division at parsing FU
From: Takashi Iwai <tiwai@xxxxxxx>
commit 8428a8ebde2db1e988e41a58497a28beb7ce1705 upstream.
parse_audio_feature_unit() contains a code dividing potentially with
zero when a malformed FU descriptor is passed. Although there is
already a sanity check, it checks only the value zero, hence it can
still lead to a zero-division when a value 1 is passed there.
Fix it by correcting the sanity check (and the error message
thereof).
Fixes: 23caaf19b11e ("ALSA: usb-mixer: Add support for Audio Class v2.0")
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
sound/usb/mixer.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -1470,9 +1470,9 @@ static int parse_audio_feature_unit(stru
return -EINVAL;
}
csize = hdr->bControlSize;
- if (!csize) {
+ if (csize <= 1) {
usb_audio_dbg(state->chip,
- "unit %u: invalid bControlSize == 0\n",
+ "unit %u: invalid bControlSize <= 1\n",
unitid);
return -EINVAL;
}
Patches currently in stable-queue which might be from tiwai@xxxxxxx are
queue-4.9/alsa-usb-audio-fix-potential-zero-division-at-parsing-fu.patch
queue-4.9/alsa-timer-remove-kernel-warning-at-compat-ioctl-error-paths.patch
queue-4.9/alsa-hda-add-raven-pci-id.patch
queue-4.9/alsa-usb-audio-add-sanity-checks-in-v2-clock-parsers.patch
queue-4.9/alsa-hda-fix-too-short-hdmi-dp-chmap-reporting.patch
queue-4.9/alsa-hda-realtek-fix-alc700-family-no-sound-issue.patch
queue-4.9/alsa-usb-audio-fix-potential-out-of-bound-access-at-parsing-su.patch
queue-4.9/alsa-pcm-update-tstamp-only-if-audio_tstamp-changed.patch
queue-4.9/alsa-usb-audio-add-sanity-checks-to-fe-parser.patch