From: "Eric W. Biederman" <ebiederm@xmission.com>

In the -mm tree the rules for access an nsproxy have changed, and in
get_net_ns_by_pid we access the nsproxy, so update it to follow the new
rules.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---


diff -puN net/core/rtnetlink.c~make-access-to-tasks-nsproxy-lighter-update-get_net_ns_by_pid net/core/rtnetlink.c
--- a/net/core/rtnetlink.c~make-access-to-tasks-nsproxy-lighter-update-get_net_ns_by_pid
+++ a/net/core/rtnetlink.c
@@ -746,10 +746,10 @@ static struct net *get_net_ns_by_pid(pid
 	rcu_read_lock();
 	tsk = find_task_by_pid(pid);
 	if (tsk) {
-		task_lock(tsk);
-		if (tsk->nsproxy)
-			net = get_net(tsk->nsproxy->net_ns);
-		task_unlock(tsk);
+		struct nsproxy *nsproxy;
+		nsproxy = task_nsproxy(tsk);
+		if (nsproxy)
+			net = get_net(nsproxy->net_ns);
 	}
 	rcu_read_unlock();
 	return net;
_