Commit d1f73f16 authored by SeungJu Cheon's avatar SeungJu Cheon Committed by Takashi Iwai
Browse files

sound: ua101: fix division by zero at probe 



Add a missing sanity check for bNrChannels in detect_usb_format()
to prevent a division by zero in playback_urb_complete() and
capture_urb_complete().

USB core does not validate class-specific descriptor fields such
as bNrChannels, so drivers must verify them before use. If a
device provides bNrChannels = 0, frame_bytes becomes zero and is
later used as a divisor in the URB completion handlers, leading
to a kernel crash.

Fixes: 63978ab3 ("sound: add Edirol UA-101 support")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarSeungJu Cheon <suunj1331@gmail.com>
Link: https://patch.msgid.link/20260426111239.103296-1-suunj1331@gmail.com


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 110189f0

sound/usb/misc/ua101.c

+7 −0
Original line number Diff line number Diff line
@@ -974,6 +974,13 @@ static int detect_usb_format(struct ua101 *ua) 


	ua->capture.channels = fmt_capture->bNrChannels;

	ua->playback.channels = fmt_playback->bNrChannels;

	if (!ua->capture.channels || !ua->playback.channels) {

		dev_err(&ua->dev->dev,

			"invalid channel count: capture %u, playback %u\n",

			ua->capture.channels, ua->playback.channels);

		return -EINVAL;

	}



	ua->capture.frame_bytes =

		fmt_capture->bSubframeSize * ua->capture.channels;

	ua->playback.frame_bytes =