[PATCH 3.16 240/254] media: v4l2-ioctl.c: don't copy back the result for -ENOTTY

From: Ben Hutchings
Date: Wed Feb 28 2018 - 11:14:29 EST


3.16.55-rc1 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>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/media/v4l2-core/v4l2-ioctl.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 16bffd851bf9..e2f71def945a 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -2402,8 +2402,11 @@ video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,

/* 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);