OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

ALSA: usb-audio: Add sanity checks in v2 clock parsers 

The helper functions to parse and look for the clock source, selector
and multiplier unit may return the descriptor with a too short length
than required, while there is no sanity check in the caller side.
Add some sanity checks in the parsers, at least, to guarantee the
given descriptor size, for avoiding the potential crashes.

Fixes: 79f920fbff ("ALSA: usb-audio: parse clock topology of UAC2 devices")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai 2017-11-21 17:28:06 +01:00
parent 8428a8ebde
commit 0a62d6c966
1 changed files with 6 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
sound/usb/clock.c
View File

@ -43,7 +43,7 @@ static struct uac_clock_source_descriptor *
while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
ctrl_iface->extralen,
cs, UAC2_CLOCK_SOURCE))) {
if (cs->bClockID == clock_id)
if (cs->bLength >= sizeof(*cs) && cs->bClockID == clock_id)
return cs;
}
@ -59,8 +59,11 @@ static struct uac_clock_selector_descriptor *
while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
ctrl_iface->extralen,
cs, UAC2_CLOCK_SELECTOR))) {
if (cs->bClockID == clock_id)
if (cs->bLength >= sizeof(*cs) && cs->bClockID == clock_id) {
if (cs->bLength < 5 + cs->bNrInPins)
return NULL;
return cs;
}
}
return NULL;
@ -75,7 +78,7 @@ static struct uac_clock_multiplier_descriptor *
while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
ctrl_iface->extralen,
cs, UAC2_CLOCK_MULTIPLIER))) {
if (cs->bClockID == clock_id)
if (cs->bLength >= sizeof(*cs) && cs->bClockID == clock_id)
return cs;
}