media: mc-device.c: don't memset __user pointer contents
authorHans Verkuil <hverkuil@xs4all.nl>
Mon, 27 May 2019 09:31:13 +0000 (05:31 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 26 Jul 2019 07:14:02 +0000 (09:14 +0200)
[ Upstream commit 518fa4e0e0da97ea2e17c95ab57647ce748a96e2 ]

You can't memset the contents of a __user pointer. Instead, call copy_to_user to
copy links.reserved (which is zeroed) to the user memory.

This fixes this sparse warning:

SPARSE:drivers/media/mc/mc-device.c drivers/media/mc/mc-device.c:521:16:  warning: incorrect type in argument 1 (different address spaces)

Fixes: f49308878d720 ("media: media_device_enum_links32: clean a reserved field")

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/media/media-device.c

index ba344e6..ed518b1 100644 (file)
@@ -503,8 +503,9 @@ static long media_device_enum_links32(struct media_device *mdev,
        if (ret)
                return ret;
 
-       memset(ulinks->reserved, 0, sizeof(ulinks->reserved));
-
+       if (copy_to_user(ulinks->reserved, links.reserved,
+                        sizeof(ulinks->reserved)))
+               return -EFAULT;
        return 0;
 }