summaryrefslogtreecommitdiffstats
path: root/sound/usb/mixer.c
diff options
context:
space:
mode:
authorTakashi Iwai <tiwai@suse.de>2017-11-21 16:55:51 +0100
committerTakashi Iwai <tiwai@suse.de>2017-11-21 17:50:29 +0100
commitd937cd6790a2bef2d07b500487646bd794c039bb (patch)
treec4bb62fe1c2cdcec12c0ed4a9725e19545b1e540 /sound/usb/mixer.c
parentALSA: timer: Remove kernel warning at compat ioctl error paths (diff)
downloadlinux-d937cd6790a2bef2d07b500487646bd794c039bb.tar.xz
linux-d937cd6790a2bef2d07b500487646bd794c039bb.zip
ALSA: usb-audio: Add sanity checks to FE parser
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@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/usb/mixer.c')
-rw-r--r--sound/usb/mixer.c12
1 files changed, 12 insertions, 0 deletions
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index 1beb5b4d027e..b8ce651e392c 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -1469,6 +1469,12 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid,
__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,
@@ -1486,6 +1492,12 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid,
}
} 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;