nfsd: use "init_net" for portmapper

commit f7fb86c6 upstream.

There could be a situation, when NFSd was started in one network namespace, but
stopped in another one.
This will trigger kernel panic, because RPCBIND client is stored on per-net
NFSd data, and will be NULL on NFSd shutdown.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Weng Meiling <wengmeiling.weng@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/nfsd/nfssvc.c

@@ -11,7 +11,6 @@
 #include <linux/module.h>
 #include <linux/fs_struct.h>
 #include <linux/swap.h>
-#include <linux/nsproxy.h>
 
 #include <linux/sunrpc/stats.h>
 #include <linux/sunrpc/svcsock.h>
@@ -330,7 +329,7 @@ static int nfsd_get_default_max_blksize(void)
 int nfsd_create_serv(void)
 {
 	int error;
-	struct net *net = current->nsproxy->net_ns;
+	struct net *net = &init_net;
 
 	WARN_ON(!mutex_is_locked(&nfsd_mutex));
 	if (nfsd_serv) {