Re: [PATCH] ALSA: usx2y: us144mkii: fix NULL deref on missing interface 0

Takashi Iwai
2026-04-09T14:41:39Z

On Thu, 09 Apr 2026 16:01:56 +0200,
Greg Kroah-Hartman wrote:
>
> A malicious USB device with the TASCAM US-144MKII device id can have a
> configuration containing bInterfaceNumber=1 but no interface 0. USB
> configuration descriptors are not required to assign interface numbers
> sequentially, so usb_ifnum_to_if(dev, 0) returns will NULL, which will
> then be dereferenced directly.
>
> Fix this up by checking the return value properly.
>
> Cc: Jaroslav Kysela <perex@perex.cz>
> Cc: Takashi Iwai <tiwai@suse.com>
> Fixes: dee1bcf28a3d ("ALSA: usx2y: Add native ALSA driver for TASCAM US-144MKII")
> Cc: stable <stable@kernel.org>
> Assisted-by: gregkh_clanker_t1000
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Applied to for-next branch now. Thanks.

Takashi