V4L/DVB (6265): Prevent for calling mmap_free without an allocated buffer

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
http://thread.gmane.org/gmane.comp.video.video4linux/34978/focus=34981
Reviewed-by: Ricardo Cerqueira <v4l@cerqueira.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/media/video/videobuf-core.c b/drivers/media/video/videobuf-core.c
index 256501384af7..eb3b98400c1b 100644
--- a/drivers/media/video/videobuf-core.c
+++ b/drivers/media/video/videobuf-core.c
@@ -880,6 +880,9 @@ int videobuf_mmap_free(struct videobuf_queue *q)
         int i;
         int rc;
 
+        if (!q)
+                return 0;
+
         MAGIC_CHECK(q->int_ops->magic,MAGIC_QTYPE_OPS);
 
         rc  = CALL(q,mmap_free,q);