[media] v4l2-event: Deny subscribing with a type of V4L2_EVENT_ALL

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/v4l2-event.c

@@ -215,6 +215,9 @@ int v4l2_event_subscribe(struct v4l2_fh *fh,
 	unsigned long flags;
 	unsigned i;
 
+	if (sub->type == V4L2_EVENT_ALL)
+		return -EINVAL;
+
 	if (elems < 1)
 		elems = 1;
 	if (sub->type == V4L2_EVENT_CTRL) {