netfilter: nf_conncount: use rb_link_node_rcu() instead of rb_link_node()

rbnode in insert_tree() is rcu protected pointer.
So, in order to handle this pointer, _rcu function should be used.
rb_link_node_rcu() is a rcu version of rb_link_node().

Fixes: 34848d5c89 ("netfilter: nf_conncount: Split insert and traversal")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/nf_conncount.c

@@ -427,7 +427,7 @@ insert_tree(struct net *net,
 	count = 1;
 	rbconn->list.count = count;
 
-	rb_link_node(&rbconn->node, parent, rbnode);
+	rb_link_node_rcu(&rbconn->node, parent, rbnode);
 	rb_insert_color(&rbconn->node, root);
 out_unlock:
 	spin_unlock_bh(&nf_conncount_locks[hash % CONNCOUNT_LOCK_SLOTS]);