[media] v4l2-dev: don't memset video_device.dev

Zeroing video_device.dev causes a memory leak if video_set_drvdata
was called before video_register_device was called. video_set_drvdata
calls dev_set_drvdata which allocates video_device.dev.p.

memsetting this will prevent freeing of that memory.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 4 insertions, 5 deletions

diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c
index 359e23290a7..341764a3a99 100644
--- a/drivers/media/video/v4l2-dev.c
+++ b/drivers/media/video/v4l2-dev.c
@@ -419,6 +419,10 @@ static int get_index(struct video_device *vdev)
  *      The registration code assigns minor numbers and device node numbers
  *      based on the requested type and registers the new device node with
  *      the kernel.
+ *
+ *      This function assumes that struct video_device was zeroed when it
+ *      was allocated and does not contain any stale date.
+ *
  *      An error is returned if no free minor or device node number could be
  *      found, or if the registration of the device node failed.
  *
@@ -440,7 +444,6 @@ static int __video_register_device(struct video_device *vdev, int type, int nr,
         int minor_offset = 0;
         int minor_cnt = VIDEO_NUM_DEVICES;
         const char *name_base;
-        void *priv = vdev->dev.p;
 
         /* A minor value of -1 marks this video device as never
            having been registered */
@@ -559,10 +562,6 @@ static int __video_register_device(struct video_device *vdev, int type, int nr,
         }
 
         /* Part 4: register the device with sysfs */
-        memset(&vdev->dev, 0, sizeof(vdev->dev));
-        /* The memset above cleared the device's device_private, so
-           put back the copy we made earlier. */
-        vdev->dev.p = priv;
         vdev->dev.class = &video_class;
         vdev->dev.devt = MKDEV(VIDEO_MAJOR, vdev->minor);
         if (vdev->parent)