ALSA: control: Avoid kernel warnings from tlv ioctl with numid 0
authorTakashi Iwai <tiwai@suse.de>
Mon, 18 Jan 2016 13:12:40 +0000 (14:12 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 31 Jan 2016 19:23:34 +0000 (11:23 -0800)
commitefcf073d7fa1aa1fb2a8d3f3db373e1a5ecbc60a
treed4f4f649d18ed62b87a399851f4ecea1d2146c46
parent965b1203f399676ac4989a0876336e212a71085b
ALSA: control: Avoid kernel warnings from tlv ioctl with numid 0

commit c0bcdbdff3ff73a54161fca3cb8b6cdbd0bb8762 upstream.

When a TLV ioctl with numid zero is handled, the driver may spew a
kernel warning with a stack trace at each call.  The check was
intended obviously only for a kernel driver, but not for a user
interaction.  Let's fix it.

This was spotted by syzkaller fuzzer.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sound/core/control.c