lkml.org 
[lkml]   [2016]   [Mar]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 2.6.32 35/55] ALSA: control: Avoid kernel warnings from tlv ioctl with numid 0
2.6.32-longterm review patch.  If anyone has any objections, please let me know.

------------------

From: Takashi Iwai <tiwai@suse.de>

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: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
sound/core/control.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/sound/core/control.c b/sound/core/control.c
index ffa7857..e6fcf56 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -1130,6 +1130,8 @@ static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
return -EFAULT;
if (tlv.length < sizeof(unsigned int) * 3)
return -EINVAL;
+ if (!tlv.numid)
+ return -EINVAL;
down_read(&card->controls_rwsem);
kctl = snd_ctl_find_numid(card, tlv.numid);
if (kctl == NULL) {
--
1.7.12.2.21.g234cd45.dirty


\
 
 \ /
  Last update: 2016-03-04 17:41    [W:0.115 / U:0.260 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site