[PATCH 3.12 141/146] media: V4L2: ov7670: fix a wrong index, potentially Oopsing the kernel from user-space

Jiri Slaby
2014-06-09T09:26:19Z

From: Guennadi Liakhovetski <g.liakhovetski@gmx.de>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit cfece5857ca51d1dcdb157017aba226f594e9dcf upstream.

Commit 75e2bdad8901a0b599e01a96229be922eef1e488 "ov7670: allow
configuration of image size, clock speed, and I/O method" uses a wrong
index to iterate an array. Apart from being wrong, it also uses an
unchecked value from user-space, which can cause access to unmapped
memory in the kernel, triggered by a normal desktop user with rights to
use V4L2 devices.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
drivers/media/i2c/ov7670.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c
index e8a1ce204036..cdd7c1b7259b 100644
--- a/drivers/media/i2c/ov7670.c
+++ b/drivers/media/i2c/ov7670.c
@@ -1109,7 +1109,7 @@ static int ov7670_enum_framesizes(struct v4l2_subdev *sd,
* windows that fall outside that.
*/
for (i = 0; i < n_win_sizes; i++) {
- struct ov7670_win_size *win = &info->devtype->win_sizes[index];
+ struct ov7670_win_size *win = &info->devtype->win_sizes[i];
if (info->min_width && win->width < info->min_width)
continue;
if (info->min_height && win->height < info->min_height)
--
1.9.3