BACKPORT: [media] uvcvideo: Fix a "ignoring return value of '__clear_user'" warning

Pulling in commit 57fb4a4831793de9e8dbdfc8dc5eb8796026d47e from
kernel-next/upstream.

Note that the directory structure has changed upstream, so that patch
does not apply to kernel-3.4 anymore.

This removes the warning:
src/third_party/kernel/files/drivers/media/video/uvc/uvc_v4l2.c:1100:14:
warning: ignoring return value of '__clear_user', declared with
attribute warn_unused_result [-Wunused-result]

BUG=chromium-os:5542
TEST=build kernel and make sure uvc_v412.c does not have this warning.

Change-Id: If4d80dcf79a750fd9b812ffe925875be9b809ec7
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Simon Que <sque@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/41470
Reviewed-by: David James <davidjames@chromium.org>

diff --git a/drivers/media/video/uvc/uvc_v4l2.c b/drivers/media/video/uvc/uvc_v4l2.c
index ff2cdddf9bc629c6d264390e6a68fb9c9c2d581a..8db90efca226367f02b650ab92872d722e21e268 100644 (file)
--- a/drivers/media/video/uvc/uvc_v4l2.c
+++ b/drivers/media/video/uvc/uvc_v4l2.c
@@ -1097,7 +1097,8 @@ static int uvc_v4l2_put_xu_mapping(const struct uvc_xu_control_mapping *kp,
            __put_user(kp->menu_count, &up->menu_count))
                return -EFAULT;
 
-       __clear_user(up->reserved, sizeof(up->reserved));
+       if (__clear_user(up->reserved, sizeof(up->reserved)))
+               return -EFAULT;
 
        if (kp->menu_count == 0)
                return 0;