From: Takashi Iwai <ti...@suse.de>
3.12-stable review patch. If anyone has any objections, please let me know.
===============
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 <dvyu...@google.com>
Signed-off-by: Takashi Iwai <ti...@suse.de>
Signed-off-by: Jiri Slaby <jsl...@suse.cz>
---
sound/core/control.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/sound/core/control.c b/sound/core/control.c
index f2082a35b890..3fcead61f0ef 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -1325,6 +1325,8 @@ static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
return -EFAULT;
if (tlv.length < sizeof(unsigned int) * 2)
return -EINVAL;
+ if (!tlv.numid)
+ return -EINVAL;
down_read(&card->controls_rwsem);
kctl = snd_ctl_find_numid(card, tlv.numid);
if (kctl == NULL) {
--
2.7.1
