3.2.99-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Takashi Iwai <[email protected]> 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 <[email protected]> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <[email protected]> --- sound/usb/mixer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -1262,9 +1262,9 @@ static int parse_audio_feature_unit(stru return -EINVAL; } csize = hdr->bControlSize; - if (!csize) { + if (csize <= 1) { snd_printdd(KERN_ERR "usbaudio: unit %u: " - "invalid bControlSize == 0\n", unitid); + "invalid bControlSize <= 1\n", unitid); return -EINVAL; } channels = (hdr->bLength - 7) / csize - 1;
