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>
Fri, 29 Jan 2016 05:49:30 +0000 (21:49 -0800)
commit2f659690fcef3c160dcd2557e724dc68ede8d90b
tree0e7e12fe3d3ffb130f80531ddf2cacdae5b8c770
parentd24455ed4c3e2220da50347700fa8aba6c3ed065
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