[PATCH 4.9 81/96] media: dmxdev: fix error code for invalid ioctls

[Greg Kroah-Hartman]

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

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

From: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>

[ Upstream commit a145f64c6107d3aa5a7cec9f8977d04ac2a896c9 ]

Returning -EINVAL when an ioctl is not implemented is a very
bad idea, as it is hard to distinguish from other error
contitions that an ioctl could lead. Replace it by its
right error code: -ENOTTY.

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/dvb-core/dmxdev.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/media/dvb-core/dmxdev.c
+++ b/drivers/media/dvb-core/dmxdev.c
@@ -1071,7 +1071,7 @@ static int dvb_demux_do_ioctl(struct fil
 		break;
 
 	default:
-		ret = -EINVAL;
+		ret = -ENOTTY;
 		break;
 	}
 	mutex_unlock(&dmxdev->mutex);