[PATCH 3.18 57/93] media: v4l2-ioctl.c: dont copy back the result for -ENOTTY

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Hans Verkuil <hans.verkuil@xxxxxxxxx>

commit 181a4a2d5a0a7b43cab08a70710d727e7764ccdd upstream.

If the ioctl returned -ENOTTY, then don't bother copying
back the result as there is no point.

Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/media/v4l2-core/v4l2-ioctl.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -2539,8 +2539,11 @@ video_usercopy(struct file *file, unsign
 
 	/* Handles IOCTL */
 	err = func(file, cmd, parg);
-	if (err == -ENOIOCTLCMD)
+	if (err == -ENOTTY || err == -ENOIOCTLCMD) {
 		err = -ENOTTY;
+		goto out;
+	}
+
 	if (err == 0) {
 		if (cmd == VIDIOC_DQBUF)
 			trace_v4l2_dqbuf(video_devdata(file)->minor, parg);