1 files changed, 59 insertions, 51 deletions

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 511f4a75149c..0c74da8a0473 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1304,16 +1304,42 @@ static void rt_del(unsigned hash, struct rtable *rt)
 	spin_unlock_bh(rt_hash_lock_addr(hash));
 }
 
+static int check_peer_redir(struct dst_entry *dst, struct inet_peer *peer)
+{
+	struct rtable *rt = (struct rtable *) dst;
+	__be32 orig_gw = rt->rt_gateway;
+	struct neighbour *n, *old_n;
+
+	dst_confirm(&rt->dst);
+
+	rt->rt_gateway = peer->redirect_learned.a4;
+
+	n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway);
+	if (IS_ERR(n))
+		return PTR_ERR(n);
+	old_n = xchg(&rt->dst._neighbour, n);
+	if (old_n)
+		neigh_release(old_n);
+	if (!n || !(n->nud_state & NUD_VALID)) {
+		if (n)
+			neigh_event_send(n, NULL);
+		rt->rt_gateway = orig_gw;
+		return -EAGAIN;
+	} else {
+		rt->rt_flags |= RTCF_REDIRECTED;
+		call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
+	}
+	return 0;
+}
+
 /* called in rcu_read_lock() section */
 void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
 		    __be32 saddr, struct net_device *dev)
 {
 	int s, i;
 	struct in_device *in_dev = __in_dev_get_rcu(dev);
-	struct rtable *rt;
 	__be32 skeys[2] = { saddr, 0 };
 	int    ikeys[2] = { dev->ifindex, 0 };
-	struct flowi4 fl4;
 	struct inet_peer *peer;
 	struct net *net;
 
@@ -1336,33 +1362,42 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
 			goto reject_redirect;
 	}
 
-	memset(&fl4, 0, sizeof(fl4));
-	fl4.daddr = daddr;
 	for (s = 0; s < 2; s++) {
 		for (i = 0; i < 2; i++) {
-			fl4.flowi4_oif = ikeys[i];
-			fl4.saddr = skeys[s];
-			rt = __ip_route_output_key(net, &fl4);
-			if (IS_ERR(rt))
-				continue;
-
-			if (rt->dst.error || rt->dst.dev != dev ||
-			    rt->rt_gateway != old_gw) {
-				ip_rt_put(rt);
-				continue;
-			}
+			unsigned int hash;
+			struct rtable __rcu **rthp;
+			struct rtable *rt;
+
+			hash = rt_hash(daddr, skeys[s], ikeys[i], rt_genid(net));
+
+			rthp = &rt_hash_table[hash].chain;
+
+			while ((rt = rcu_dereference(*rthp)) != NULL) {
+				rthp = &rt->dst.rt_next;
+
+				if (rt->rt_key_dst != daddr ||
+				    rt->rt_key_src != skeys[s] ||
+				    rt->rt_oif != ikeys[i] ||
+				    rt_is_input_route(rt) ||
+				    rt_is_expired(rt) ||
+				    !net_eq(dev_net(rt->dst.dev), net) ||
+				    rt->dst.error ||
+				    rt->dst.dev != dev ||
+				    rt->rt_gateway != old_gw)
+					continue;
 
-			if (!rt->peer)
-				rt_bind_peer(rt, rt->rt_dst, 1);
+				if (!rt->peer)
+					rt_bind_peer(rt, rt->rt_dst, 1);
 
-			peer = rt->peer;
-			if (peer) {
-				peer->redirect_learned.a4 = new_gw;
-				atomic_inc(&__rt_peer_genid);
+				peer = rt->peer;
+				if (peer) {
+					if (peer->redirect_learned.a4 != new_gw) {
+						peer->redirect_learned.a4 = new_gw;
+						atomic_inc(&__rt_peer_genid);
+					}
+					check_peer_redir(&rt->dst, peer);
+				}
 			}
-
-			ip_rt_put(rt);
-			return;
 		}
 	}
 	return;
@@ -1649,33 +1684,6 @@ static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
 	}
 }
 
-static int check_peer_redir(struct dst_entry *dst, struct inet_peer *peer)
-{
-	struct rtable *rt = (struct rtable *) dst;
-	__be32 orig_gw = rt->rt_gateway;
-	struct neighbour *n, *old_n;
-
-	dst_confirm(&rt->dst);
-
-	rt->rt_gateway = peer->redirect_learned.a4;
-
-	n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway);
-	if (IS_ERR(n))
-		return PTR_ERR(n);
-	old_n = xchg(&rt->dst._neighbour, n);
-	if (old_n)
-		neigh_release(old_n);
-	if (!n || !(n->nud_state & NUD_VALID)) {
-		if (n)
-			neigh_event_send(n, NULL);
-		rt->rt_gateway = orig_gw;
-		return -EAGAIN;
-	} else {
-		rt->rt_flags |= RTCF_REDIRECTED;
-		call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
-	}
-	return 0;
-}
 
 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
 {