The following change since commit 29594404d7fe73cd80eaa4ee8c43dcc53970c60e:
Linux 3.7 (2012-12-10 19:30:57 -0800)
is available in the git repository at:
git://git.alsa-project.org/alsa-kprivate.git usb-audio-fix
for you to fetch changes up to 5fcbad428a81efa318f15bfcfbcd8f0a98ec0b11:
ALSA: usb-audio: fix invalid length check for RME and other UAC 2 devices (2013-01-26 17:49:35 +0100)
---------------------------------------------------------------- Clemens Ladisch (1): ALSA: usb-audio: fix invalid length check for RME and other UAC 2 devices
sound/usb/mixer.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-)
ALSA: usb-audio: fix invalid length check for RME and other UAC 2 devices
Commit 23caaf19b11e (ALSA: usb-mixer: Add support for Audio Class v2.0) forgot to adjust the length check for UAC 2.0 feature unit descriptors. This would make the code abort on encountering a feature unit without per-channel controls, and thus prevented the driver to work with any device having such a unit, such as the RME Babyface or Fireface UCX.
Reported-by: Florian Hanisch fhanisch@uni-potsdam.de Tested-by: Matthew Robbetts wingfeathera@gmail.com Tested-by: Michael Beer beerml@sigma6audio.de Cc: Daniel Mack daniel@caiaq.de Cc: 2.6.35+ stable@vger.kernel.org Signed-off-by: Clemens Ladisch clemens@ladisch.de
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index 298070e..41e8bfb 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -1259,16 +1259,23 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid, void } channels = (hdr->bLength - 7) / csize - 1; bmaControls = hdr->bmaControls; + if (hdr->bLength < 7 + csize) { + snd_printk(KERN_ERR "usbaudio: unit %u: " + "invalid UAC_FEATURE_UNIT descriptor\n", + unitid); + return -EINVAL; + } } else { struct uac2_feature_unit_descriptor *ftr = _ftr; csize = 4; channels = (hdr->bLength - 6) / 4 - 1; bmaControls = ftr->bmaControls; - } - - if (hdr->bLength < 7 || !csize || hdr->bLength < 7 + csize) { - snd_printk(KERN_ERR "usbaudio: unit %u: invalid UAC_FEATURE_UNIT descriptor\n", unitid); - return -EINVAL; + if (hdr->bLength < 6 + csize) { + snd_printk(KERN_ERR "usbaudio: unit %u: " + "invalid UAC_FEATURE_UNIT descriptor\n", + unitid); + return -EINVAL; + } }
/* parse the source unit */