From 0010e46577a27c1d915034637f6c2fa57a9a091c Mon Sep 17 00:00:00 2001 From: Timo Teras Date: Tue, 29 Apr 2008 03:32:25 -0700 Subject: [PATCH] ipv4: Update MTU to all related cache entries in ip_rt_frag_needed() Add struct net_device parameter to ip_rt_frag_needed() and update MTU to cache entries where ifindex is specified. This is similar to what is already done in ip_rt_redirect(). Signed-off-by: Timo Teras Signed-off-by: David S. Miller --- include/net/route.h | 2 +- net/ipv4/icmp.c | 3 ++- net/ipv4/route.c | 38 ++++++++++++++++++++++---------------- 3 files changed, 25 insertions(+), 18 deletions(-) diff --git a/include/net/route.h b/include/net/route.h index c6338802e8f..fc836ff824c 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -116,7 +116,7 @@ extern int __ip_route_output_key(struct net *, struct rtable **, const struct f extern int ip_route_output_key(struct net *, struct rtable **, struct flowi *flp); extern int ip_route_output_flow(struct net *, struct rtable **rp, struct flowi *flp, struct sock *sk, int flags); extern int ip_route_input(struct sk_buff*, __be32 dst, __be32 src, u8 tos, struct net_device *devin); -extern unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph, unsigned short new_mtu); +extern unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph, unsigned short new_mtu, struct net_device *dev); extern void ip_rt_send_redirect(struct sk_buff *skb); extern unsigned inet_addr_type(struct net *net, __be32 addr); diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index c67d00e8c60..87397351dda 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -691,7 +691,8 @@ static void icmp_unreach(struct sk_buff *skb) NIPQUAD(iph->daddr)); } else { info = ip_rt_frag_needed(net, iph, - ntohs(icmph->un.frag.mtu)); + ntohs(icmph->un.frag.mtu), + skb->dev); if (!info) goto out; } diff --git a/net/ipv4/route.c b/net/ipv4/route.c index ce25a13f343..5e3685c5c40 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1430,11 +1430,13 @@ static inline unsigned short guess_mtu(unsigned short old_mtu) } unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph, - unsigned short new_mtu) + unsigned short new_mtu, + struct net_device *dev) { - int i; + int i, k; unsigned short old_mtu = ntohs(iph->tot_len); struct rtable *rth; + int ikeys[2] = { dev->ifindex, 0 }; __be32 skeys[2] = { iph->saddr, 0, }; __be32 daddr = iph->daddr; unsigned short est_mtu = 0; @@ -1442,22 +1444,26 @@ unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph, if (ipv4_config.no_pmtu_disc) return 0; - for (i = 0; i < 2; i++) { - unsigned hash = rt_hash(daddr, skeys[i], 0); + for (k = 0; k < 2; k++) { + for (i = 0; i < 2; i++) { + unsigned hash = rt_hash(daddr, skeys[i], ikeys[k]); - rcu_read_lock(); - for (rth = rcu_dereference(rt_hash_table[hash].chain); rth; - rth = rcu_dereference(rth->u.dst.rt_next)) { - if (rth->fl.fl4_dst == daddr && - rth->fl.fl4_src == skeys[i] && - rth->rt_dst == daddr && - rth->rt_src == iph->saddr && - rth->fl.iif == 0 && - !(dst_metric_locked(&rth->u.dst, RTAX_MTU)) && - net_eq(dev_net(rth->u.dst.dev), net) && - rth->rt_genid == atomic_read(&rt_genid)) { + rcu_read_lock(); + for (rth = rcu_dereference(rt_hash_table[hash].chain); rth; + rth = rcu_dereference(rth->u.dst.rt_next)) { unsigned short mtu = new_mtu; + if (rth->fl.fl4_dst != daddr || + rth->fl.fl4_src != skeys[i] || + rth->rt_dst != daddr || + rth->rt_src != iph->saddr || + rth->fl.oif != ikeys[k] || + rth->fl.iif != 0 || + dst_metric_locked(&rth->u.dst, RTAX_MTU) || + !net_eq(dev_net(rth->u.dst.dev), net) || + rth->rt_genid != atomic_read(&rt_genid)) + continue; + if (new_mtu < 68 || new_mtu >= old_mtu) { /* BSD 4.2 compatibility hack :-( */ @@ -1483,8 +1489,8 @@ unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph, est_mtu = mtu; } } + rcu_read_unlock(); } - rcu_read_unlock(); } return est_mtu ? : new_mtu; } -- 2.41.1