Re: [PATCH 5.2 03/20] ALSA: usb-audio: Sanity checks for each pipe and EP types

From: Sasha Levin
Date: Fri Aug 02 2019 - 09:48:31 EST


On Fri, Aug 02, 2019 at 11:39:57AM +0200, Greg Kroah-Hartman wrote:
From: Takashi Iwai <tiwai@xxxxxxx>

commit 801ebf1043ae7b182588554cc9b9ad3c14bc2ab5 upstream.

The recent USB core code performs sanity checks for the given pipe and
EP types, and it can be hit by manipulated USB descriptors by syzbot.
For making syzbot happier, this patch introduces a local helper for a
sanity check in the driver side and calls it at each place before the
message handling, so that we can avoid the WARNING splats.

Reported-by: syzbot+d952e5e28f5fb7718d23@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

This commit has a fix: 5d78e1c2b7f4b ("ALSA: usb-audio: Fix gpf in
snd_usb_pipe_sanity_check") which was not pulled by Linus yet.

I'm going to drop this commit and re-queue it together with it's fix
once it makes it upstream.

--
Thanks,
Sasha