Commit efbc368d authored by David S. Miller's avatar David S. Miller
Browse files

ipv4: Perform peer validation on cached route lookup. 



Otherwise we won't notice the peer GENID change.

Reported-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 8f891489

net/ipv4/route.c

+19 −7
Original line number Diff line number Diff line
@@ -1693,12 +1693,8 @@ static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu) 
}





static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)

static struct rtable *ipv4_validate_peer(struct rtable *rt)

{

	struct rtable *rt = (struct rtable *) dst;



	if (rt_is_expired(rt))

		return NULL;

	if (rt->rt_peer_genid != rt_peer_genid()) {

		struct inet_peer *peer;
@@ -1707,19 +1703,29 @@ static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) 


		peer = rt->peer;

		if (peer) {

			check_peer_pmtu(dst, peer);

			check_peer_pmtu(&rt->dst, peer);



			if (peer->redirect_genid != redirect_genid)

				peer->redirect_learned.a4 = 0;

			if (peer->redirect_learned.a4 &&

			    peer->redirect_learned.a4 != rt->rt_gateway) {

				if (check_peer_redir(dst, peer))

				if (check_peer_redir(&rt->dst, peer))

					return NULL;

			}

		}



		rt->rt_peer_genid = rt_peer_genid();

	}

	return rt;

}



static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)

{

	struct rtable *rt = (struct rtable *) dst;



	if (rt_is_expired(rt))

		return NULL;

	dst = (struct dst_entry *) ipv4_validate_peer(rt);

	return dst;

}
@@ -2374,6 +2380,9 @@ int ip_route_input_common(struct sk_buff *skb, __be32 daddr, __be32 saddr, 
		    rth->rt_mark == skb->mark &&

		    net_eq(dev_net(rth->dst.dev), net) &&

		    !rt_is_expired(rth)) {

			rth = ipv4_validate_peer(rth);

			if (!rth)

				continue;

			if (noref) {

				dst_use_noref(&rth->dst, jiffies);

				skb_dst_set_noref(skb, &rth->dst);
@@ -2749,6 +2758,9 @@ struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *flp4) 
			    (IPTOS_RT_MASK | RTO_ONLINK)) &&

		    net_eq(dev_net(rth->dst.dev), net) &&

		    !rt_is_expired(rth)) {

			rth = ipv4_validate_peer(rth);

			if (!rth)

				continue;

			dst_use(&rth->dst, jiffies);

			RT_CACHE_STAT_INC(out_hit);

			rcu_read_unlock_bh();