diff options
| author | Sakari Ailus <[email protected]> | 2016-04-03 16:31:03 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <[email protected]> | 2016-04-13 16:20:01 -0300 |
| commit | 2c1f6951a8a82e6de0d82b1158b5e493fc6c54ab (patch) | |
| tree | 78e2a25eed9562278421f656904ebe8f30eff863 | |
| parent | e7e0c3e26587749b62d17b9dd0532874186c77f7 (diff) | |
[media] videobuf2-v4l2: Verify planes array in buffer dequeueing
When a buffer is being dequeued using VIDIOC_DQBUF IOCTL, the exact buffer
which will be dequeued is not known until the buffer has been removed from
the queue. The number of planes is specific to a buffer, not to the queue.
This does lead to the situation where multi-plane buffers may be requested
and queued with n planes, but VIDIOC_DQBUF IOCTL may be passed an argument
struct with fewer planes.
__fill_v4l2_buffer() however uses the number of planes from the dequeued
videobuf2 buffer, overwriting kernel memory (the m.planes array allocated
in video_usercopy() in v4l2-ioctl.c) if the user provided fewer
planes than the dequeued buffer had. Oops!
Fixes: b0e0e1f83de3 ("[media] media: videobuf2: Prepare to divide videobuf2")
Signed-off-by: Sakari Ailus <[email protected]>
Acked-by: Hans Verkuil <[email protected]>
Cc: [email protected] # for v4.4 and later
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
| -rw-r--r-- | drivers/media/v4l2-core/videobuf2-v4l2.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/videobuf2-v4l2.c b/drivers/media/v4l2-core/videobuf2-v4l2.c index 91f552124050..8da7470ca364 100644 --- a/drivers/media/v4l2-core/videobuf2-v4l2.c +++ b/drivers/media/v4l2-core/videobuf2-v4l2.c @@ -74,6 +74,11 @@ static int __verify_planes_array(struct vb2_buffer *vb, const struct v4l2_buffer return 0; } +static int __verify_planes_array_core(struct vb2_buffer *vb, const void *pb) +{ + return __verify_planes_array(vb, pb); +} + /** * __verify_length() - Verify that the bytesused value for each plane fits in * the plane length and that the data offset doesn't exceed the bytesused value. @@ -437,6 +442,7 @@ static int __fill_vb2_buffer(struct vb2_buffer *vb, } static const struct vb2_buf_ops v4l2_buf_ops = { + .verify_planes_array = __verify_planes_array_core, .fill_user_buffer = __fill_v4l2_buffer, .fill_vb2_buffer = __fill_vb2_buffer, .copy_timestamp = __copy_timestamp, |