[PATCH] userns: fix return value on mntns_install() failure

[Eric W. Biederman]

Zhao Hongjiang <zhaohongjiang37 at gmail.com> writes:

> From: Zhao Hongjiang <zhaohongjiang at huawei.com>
>
> Change return value from -EINVAL to -EPERM when the permission check
> fails.

Thanks applied.

Eric