nfsd4: 4.1 SECINFO should consume filehandle

See the referenced spec language; an attempt by a 4.1 client to use the
current filehandle after a secinfo call should result in a NOFILEHANDLE
error.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 0cdfd02..bad4bf8 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -769,6 +769,9 @@
 	} else
 		secinfo->si_exp = exp;
 	dput(dentry);
+	if (cstate->minorversion)
+		/* See rfc 5661 section 2.6.3.1.1.8 */
+		fh_put(&cstate->current_fh);
 	return err;
 }