summaryrefslogtreecommitdiff
path: root/net
diff options
context:
space:
mode:
authorEric Dumazet <eric.dumazet@gmail.com>2011-11-18 15:24:32 -0500
committerGreg Kroah-Hartman <gregkh@suse.de>2011-12-09 08:56:06 -0800
commit427814da7d68739ec2c53a9433f62323c68ef34d (patch)
tree4bc41b28205db8eff0f83ed0130a1fb6756d51b4 /net
parent5c9c7437749337f1af355eb9e447e75a58822da4 (diff)
ipv4: fix redirect handling
[ Upstream commit 9cc20b268a5a14f5e57b8ad405a83513ab0d78dc ] commit f39925dbde77 (ipv4: Cache learned redirect information in inetpeer.) introduced a regression in ICMP redirect handling. It assumed ipv4_dst_check() would be called because all possible routes were attached to the inetpeer we modify in ip_rt_redirect(), but thats not true. commit 7cc9150ebe (route: fix ICMP redirect validation) tried to fix this but solution was not complete. (It fixed only one route) So we must lookup existing routes (including different TOS values) and call check_peer_redir() on them. Reported-by: Ivan Zahariev <famzah@icdsoft.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Flavio Leitner <fbl@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'net')
-rw-r--r--net/ipv4/route.c110
1 files changed, 59 insertions, 51 deletions
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index e9b273b923e7..b2e9544a543d 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1309,16 +1309,42 @@ 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;
@@ -1341,33 +1367,42 @@ 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;
@@ -1654,33 +1689,6 @@ 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)
{