[ Upstream commit 02241995 ]

The function should return -EFAULT when copy_from_user fails. Even
though the caller does not distinguish them. but we should keep backward
compatibility.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>