chown to file on NFS4 changes owner to "nobody"

[Chris Johnson]

Linux blackboard 3.5.0-19-generic #30-Ubuntu SMP Tue Nov 13 17:48:01 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

cjohnson@blackboard:~$ more /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=12.10
DISTRIB_CODENAME=quantal
DISTRIB_DESCRIPTION="Ubuntu 12.10"

Summary:
chown by root on a nfs4 mounted directory changes the owner to nobody
chgroup by root on a nfs4 mounted directory changes the group to nogroup

How to duplicate
Set up a NFS4 server.

# mount -t nfs4 server:cjohnson /home/cjohnson
# touch /home/cjohnson/junk
# ls -l /home/cjohnson/junk
-rw-rw-r-- 1 root root 0 Nov 30 15:36 /home/cjohnson/junk
# chown cjohnson.cjohnson /home/cjohnson/junk
# ls -l /home/cjohnson/junk
-rw-rw-r-- 1 nobody nogroup 0 Nov 30 15:36 /home/cjohnson/junk

# rm /home/cjohnson/junk
# umount /home/cjohnson
# mount server:/home/cjohnson /home/cjohnson # NFS v3
(everything works as it should)

This behavior changed on upgrade from 12.04 to 12.10.

LDAP is turned off, autofs is turned off but those WERE used prior to this bug being discovered. UIDs and GIDs match on server and client.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.