FreeBSD -- Incorrect privilege validation in the NFS server

Problem Description:
The kernel incorrectly uses client supplied credentials
instead of the one configured in exports(5) when filling out the
anonymous credential for a NFS export, when -network or -host
restrictions are used at the same time.
Impact:
The remote client may supply privileged credentials (e.g. the
root user) when accessing a file under the NFS share, which will bypass
the normal access checks.