net_ns: add __rcu annotations

add __rcu annotation to (struct net)->gen, and use rcu_dereference_protected() in net_assign_generic() Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
git-mirror · Oct 25, 2010 · 1c87733 · 1c87733
1 parent 6e3f7fa
commit 1c87733
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Showing 2 changed files with 4 additions and 2 deletions.
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
@@ -88,7 +88,7 @@ struct net {
 #ifdef CONFIG_WEXT_CORE
 	struct sk_buff_head	wext_nlevents;
 #endif
-	struct net_generic	*gen;
+	struct net_generic __rcu	*gen;
 
 	/* Note : following structs are cache line aligned */
 #ifdef CONFIG_XFRM

diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
@@ -42,7 +42,9 @@ static int net_assign_generic(struct net *net, int id, void *data)
 	BUG_ON(!mutex_is_locked(&net_mutex));
 	BUG_ON(id == 0);
 
-	ng = old_ng = net->gen;
+	old_ng = rcu_dereference_protected(net->gen,
+					   lockdep_is_held(&net_mutex));
+	ng = old_ng;
 	if (old_ng->len >= id)
 		goto assign;