From de68dca1816660b0d3ac89fa59ffb410007a143f Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 26 Nov 2011 12:13:44 +0000 Subject: [PATCH] inet: add a redirect generation id in inetpeer MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Now inetpeer is the place where we cache redirect information for ipv4 destinations, we must be able to invalidate informations when a route is added/removed on host. As inetpeer is not yet namespace aware, this patch adds a shared redirect_genid, and a per inetpeer redirect_genid. This might be changed later if inetpeer becomes ns aware. Cache information for one inerpeer is valid as long as its redirect_genid has the same value than global redirect_genid. Reported-by: Arkadiusz Miśkiewicz Tested-by: Arkadiusz Miśkiewicz Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/inetpeer.h | 1 + net/ipv4/route.c | 10 +++++++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/include/net/inetpeer.h b/include/net/inetpeer.h index 78c83e62218f..e9ff3fc5e688 100644 --- a/include/net/inetpeer.h +++ b/include/net/inetpeer.h @@ -35,6 +35,7 @@ struct inet_peer { u32 metrics[RTAX_MAX]; u32 rate_tokens; /* rate limiting for ICMP */ + int redirect_genid; unsigned long rate_last; unsigned long pmtu_expires; u32 pmtu_orig; diff --git a/net/ipv4/route.c b/net/ipv4/route.c index fb47c8f0cd86..5c2847247f51 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -131,6 +131,7 @@ static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ; static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20; static int ip_rt_min_advmss __read_mostly = 256; static int rt_chain_length_max __read_mostly = 20; +static int redirect_genid; /* * Interface to generic destination cache. @@ -837,6 +838,7 @@ static void rt_cache_invalidate(struct net *net) get_random_bytes(&shuffle, sizeof(shuffle)); atomic_add(shuffle + 1U, &net->ipv4.rt_genid); + redirect_genid++; } /* @@ -1391,8 +1393,10 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, peer = rt->peer; if (peer) { - if (peer->redirect_learned.a4 != new_gw) { + if (peer->redirect_learned.a4 != new_gw || + peer->redirect_genid != redirect_genid) { peer->redirect_learned.a4 = new_gw; + peer->redirect_genid = redirect_genid; atomic_inc(&__rt_peer_genid); } check_peer_redir(&rt->dst, peer); @@ -1701,6 +1705,8 @@ static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) if (peer) { check_peer_pmtu(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)) @@ -1857,6 +1863,8 @@ static void rt_init_metrics(struct rtable *rt, const struct flowi4 *fl4, dst_init_metrics(&rt->dst, peer->metrics, false); 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) { rt->rt_gateway = peer->redirect_learned.a4; -- 2.30.2