s3: winbind: Prevent null ptr access by returning error if no creds available
Prevent rpccli_netlogon_network_logon/rpccli_netlogon_password_logon
being called with 'NULL' credentials
BUG: https://bugzilla.samba.org/show_bug.cgi?id=11569
Signed-off-by: Noel Power <noel.power@suse.com>
Reviewed-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
(cherry picked from commit
e8fab02773892812f563eea7098847618df76e1b)
Autobuild-User(v4-2-test): Karolin Seeger <kseeger@samba.org>
Autobuild-Date(v4-2-test): Mon Nov 16 12:55:13 CET 2015 on sn-devel-104