CVE request: kernel: set cred->user_ns in key_replace_session_keyring

[Eugene Teo <eugene () redhat com>]

new->user_ns is uninitialised if the cred is not created with
copy_creds(). If I'm not mistaken, this was introduced by
47a150edc2ae734c0f4bf50aa19499 (v2.6.39).

Thread starts from https://lkml.org/lkml/2011/5/23/199;
Proposed patch: https://lkml.org/lkml/2011/5/25/265

Thanks, Eugene