Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

[media] v4l: Fix use-after-free case in v4l2_device_release

Browse source 
Drivers that have no v4l2_device release callback might free the
v4l2_device instance in the video_device release callback. Make sure we
don't access the v4l2_device instance after it gets freed.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Hans Verkuil 2011-09-06 10:23:18 -03:00 committed by Mauro Carvalho Chehab
parent dd182e5416
commit 8280b662df
1 changed files with 11 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

11
drivers/media/video/v4l2-dev.c
View file

@ -173,6 +173,17 @@ static void v4l2_device_release(struct device *cd)
media_device_unregister_entity(&vdev->entity);
#endif
/* Do not call v4l2_device_put if there is no release callback set.
* Drivers that have no v4l2_device release callback might free the
* v4l2_dev instance in the video_device release callback below, so we
* must perform this check here.
*
* TODO: In the long run all drivers that use v4l2_device should use the
* v4l2_device release callback. This check will then be unnecessary.
*/
if (v4l2_dev->release == NULL)
v4l2_dev = NULL;
/* Release video_device and perform other
cleanups as needed. */
vdev->release(vdev);