4.7-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sakari Ailus <sakari.ai...@linux.intel.com>
commit 126f40298446a82116e1f92a1aaf72b8c8228fae upstream.
An earlier patch fixing an input validation issue introduced another
issue: vb2_core_dqbuf() is called with pb argument value NULL in some
cases, causing a NULL pointer dereference. Fix this by skipping the
verification as there's nothing to verify.
Fixes: e7e0c3e26587 ("[media] videobuf2-core: Check user space planes array in
dqbuf")
Signed-off-by: David R <da...@unsolicited.net>
Signed-off-by: Sakari Ailus <sakari.ai...@linux.intel.com>
Reviewed-by: Hans Verkuil <hans.verk...@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mche...@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
drivers/media/v4l2-core/videobuf2-core.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
--- a/drivers/media/v4l2-core/videobuf2-core.c
+++ b/drivers/media/v4l2-core/videobuf2-core.c
@@ -1648,7 +1648,7 @@ static int __vb2_get_done_vb(struct vb2_
void *pb, int nonblocking)
{
unsigned long flags;
- int ret;
+ int ret = 0;
/*
* Wait for at least one buffer to become available on the done_list.
@@ -1664,10 +1664,12 @@ static int __vb2_get_done_vb(struct vb2_
spin_lock_irqsave(&q->done_lock, flags);
*vb = list_first_entry(&q->done_list, struct vb2_buffer, done_entry);
/*
- * Only remove the buffer from done_list if v4l2_buffer can handle all
- * the planes.
+ * Only remove the buffer from done_list if all planes can be
+ * handled. Some cases such as V4L2 file I/O and DVB have pb
+ * == NULL; skip the check then as there's nothing to verify.
*/
- ret = call_bufop(q, verify_planes_array, *vb, pb);
+ if (pb)
+ ret = call_bufop(q, verify_planes_array, *vb, pb);
if (!ret)
list_del(&(*vb)->done_entry);
spin_unlock_irqrestore(&q->done_lock, flags);
