[PATCH 5.15 118/181] ALSA: usb-audio: Drop snd_BUG_ON() from snd_usbmidi_output_open()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Takashi Iwai <tiwai@xxxxxxx>

commit ad72c3c3f6eb81d2cb189ec71e888316adada5df upstream.

snd_usbmidi_output_open() has a check of the NULL port with
snd_BUG_ON().  snd_BUG_ON() was used as this shouldn't have happened,
but in reality, the NULL port may be seen when the device gives an
invalid endpoint setup at the descriptor, hence the driver skips the
allocation.  That is, the check itself is valid and snd_BUG_ON()
should be dropped from there.  Otherwise it's confusing as if it were
a real bug, as recently syzbot stumbled on it.

Reported-by: syzbot+9abda841d636d86c41da@xxxxxxxxxxxxxxxxxxxxxxxxx
Cc: <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/syzbot+9abda841d636d86c41da@xxxxxxxxxxxxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20221112141223.6144-1-tiwai@xxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 sound/usb/midi.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

--- a/sound/usb/midi.c
+++ b/sound/usb/midi.c
@@ -1133,10 +1133,8 @@ static int snd_usbmidi_output_open(struc
 					port = &umidi->endpoints[i].out->ports[j];
 					break;
 				}
-	if (!port) {
-		snd_BUG();
+	if (!port)
 		return -ENXIO;
-	}
 
 	substream->runtime->private_data = port;
 	port->state = STATE_UNKNOWN;





[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux