This is a note to let you know that I've just added the patch titled ALSA: usb-audio: Fix potential out-of-bound access at parsing SU 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-fix-potential-out-of-bound-access-at-parsing-su.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 f658f17b5e0e339935dca23e77e0f3cad591926b Mon Sep 17 00:00:00 2001 From: Takashi Iwai <tiwai@xxxxxxx> Date: Tue, 21 Nov 2017 17:00:32 +0100 Subject: ALSA: usb-audio: Fix potential out-of-bound access at parsing SU From: Takashi Iwai <tiwai@xxxxxxx> commit f658f17b5e0e339935dca23e77e0f3cad591926b upstream. The usb-audio driver may trigger an out-of-bound access at parsing a malformed selector unit, as it checks the header length only after evaluating bNrInPins field, which can be already above the given length. Fix it by adding the length check beforehand. Fixes: 99fc86450c43 ("ALSA: usb-mixer: parse descriptors with structs") Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- sound/usb/mixer.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -2018,7 +2018,8 @@ static int parse_audio_selector_unit(str const struct usbmix_name_map *map; char **namelist; - if (!desc->bNrInPins || desc->bLength < 5 + desc->bNrInPins) { + if (desc->bLength < 5 || !desc->bNrInPins || + desc->bLength < 5 + desc->bNrInPins) { usb_audio_err(state->chip, "invalid SELECTOR UNIT descriptor %d\n", unitid); return -EINVAL; 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