Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0010e465 authored by Timo Teras's avatar Timo Teras Committed by David S. Miller
Browse files

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: default avatarTimo Teras <timo.teras@iki.fi>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 980c478d

include/net/route.h

+1 −1
Original line number Diff line number Diff line
@@ -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);

net/ipv4/icmp.c

+2 −1
Original line number Diff line number Diff line
@@ -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;

			}

net/ipv4/route.c

+22 −16
Original line number Diff line number Diff line
@@ -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 (k = 0; k < 2; k++) {

		for (i = 0; i < 2; i++) {

		unsigned hash = rt_hash(daddr, skeys[i], 0);

			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)) {

				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 :-( */
@@ -1483,9 +1489,9 @@ unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph, 
					est_mtu = mtu;

				}

			}

		}

			rcu_read_unlock();

		}

	}

	return est_mtu ? : new_mtu;

}