NFSv4: nfs4_proc_set_acl needs to restore NFS_CAP_UIDGID_NOMAP on error.

commit f8849e20

 upstream.

Currently if __nfs4_proc_set_acl fails with NFS4ERR_BADOWNER it
re-enables the idmapper by clearing NFS_CAP_UIDGID_NOMAP before
retrying again. The NFS_CAP_UIDGID_NOMAP remains cleared even if
the retry fails. This causes problem for subsequent setattr
requests for v4 server that does not have idmapping configured.

This patch modifies nfs4_proc_set_acl to detect NFS4ERR_BADOWNER
and NFS4ERR_BADNAME and skips the retry, since the kernel isn't
involved in encoding the ACEs, and return -EINVAL.

Steps to reproduce the problem:

 # mount -o vers=4.1,sec=sys server:/export/test /tmp/mnt
 # touch /tmp/mnt/file1
 # chown 99 /tmp/mnt/file1
 # nfs4_setfacl -a A::unknown.user@xyz.com:wrtncy /tmp/mnt/file1
 Failed setxattr operation: Invalid argument
 # chown 99 /tmp/mnt/file1
 chown: changing ownership of ‘/tmp/mnt/file1’: Invalid argument
 # umount /tmp/mnt
 # mount -o vers=4.1,sec=sys server:/export/test /tmp/mnt
 # chown 99 /tmp/mnt/file1
 #

v2: detect NFS4ERR_BADOWNER and NFS4ERR_BADNAME and skip retry
       in nfs4_proc_set_acl.
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>