diff --git a/include/net/route.h b/include/net/route.h
index a36ae429ed5dcc3ec2b66c0e064b678bafb0fc2e..47eb25ac1f7f8bce86a0cb608382bd1d0c6ee4e3 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -215,7 +215,10 @@ static inline int ip_route_input_noref(struct sk_buff *skb, __be32 dst, __be32 s
return ip_route_input_common(skb, dst, src, tos, devin, true);
}
-extern void ip_rt_send_redirect(struct sk_buff *skb);
+extern void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu,
+ int oif, u32 mark, u8 protocol, int flow_flags);
+extern void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu);
+extern void ip_rt_send_redirect(struct sk_buff *skb);
extern unsigned int inet_addr_type(struct net *net, __be32 addr);
extern unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev, __be32 addr);
diff --git a/net/ipv4/ah4.c b/net/ipv4/ah4.c
index e8f2617ecd471dad3c0aafe6db9c31adfb39d730..916d5ecaf6c698fcce1c71006ac3c2edf187ff0f 100644
--- a/net/ipv4/ah4.c
+++ b/net/ipv4/ah4.c
@@ -408,6 +408,7 @@ static void ah4_err(struct sk_buff *skb, u32 info)
return;
pr_debug("pmtu discovery on SA AH/%08x/%08x\n",
ntohl(ah->spi), ntohl(iph->daddr));
+ ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_AH, 0);
xfrm_state_put(x);
}
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index cb982a61536fade811908a18e6119f513914741e..7b95b49a36cea37d2a18720b7e13c10fadb4506d 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -494,6 +494,7 @@ static void esp4_err(struct sk_buff *skb, u32 info)
return;
NETDEBUG(KERN_DEBUG "pmtu discovery on SA ESP/%08x/%08x\n",
ntohl(esph->spi), ntohl(iph->daddr));
+ ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ESP, 0);
xfrm_state_put(x);
}
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index f49047b796096d1ce8ccd577db04556b576bc120..594cec35ac4df198b4afb956104c1e5120c8c0ed 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -516,9 +516,6 @@ static void ipgre_err(struct sk_buff *skb, u32 info)
case ICMP_PORT_UNREACH:
/* Impossible event. */
return;
- case ICMP_FRAG_NEEDED:
- /* Soft state for pmtu is maintained by IP core. */
- return;
default:
/* All others are translated to HOST_UNREACH.
rfc2003 contains "deep thoughts" about NET_UNREACH,
@@ -538,7 +535,16 @@ static void ipgre_err(struct sk_buff *skb, u32 info)
flags & GRE_KEY ?
*(((__be32 *)p) + (grehlen / 4) - 1) : 0,
p[1]);
- if (t == NULL || t->parms.iph.daddr == 0 ||
+ if (t == NULL)
+ goto out;
+
+ if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
+ ipv4_update_pmtu(skb, dev_net(skb->dev), info,
+ t->parms.link, 0, IPPROTO_GRE, 0);
+ goto out;
+ }
+
+ if (t->parms.iph.daddr == 0 ||
ipv4_is_multicast(t->parms.iph.daddr))
goto out;
diff --git a/net/ipv4/ipcomp.c b/net/ipv4/ipcomp.c
index 63b64c45a826391bf4eded1f70b006efdd5a8e36..b91375482d844c9f9cfa0011faef541462c7349f 100644
--- a/net/ipv4/ipcomp.c
+++ b/net/ipv4/ipcomp.c
@@ -42,6 +42,7 @@ static void ipcomp4_err(struct sk_buff *skb, u32 info)
return;
NETDEBUG(KERN_DEBUG "pmtu discovery on SA IPCOMP/%08x/%pI4\n",
spi, &iph->daddr);
+ ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_COMP, 0);
xfrm_state_put(x);
}
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index 2d0f99bf61b348e70d1f90308d3a0119a358f563..715338a1b205a07195e31878f50cdbef31864c86 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -348,9 +348,6 @@ static int ipip_err(struct sk_buff *skb, u32 info)
case ICMP_PORT_UNREACH:
/* Impossible event. */
return 0;
- case ICMP_FRAG_NEEDED:
- /* Soft state for pmtu is maintained by IP core. */
- return 0;
default:
/* All others are translated to HOST_UNREACH.
rfc2003 contains "deep thoughts" about NET_UNREACH,
@@ -369,7 +366,17 @@ static int ipip_err(struct sk_buff *skb, u32 info)
rcu_read_lock();
t = ipip_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
- if (t == NULL || t->parms.iph.daddr == 0)
+ if (t == NULL)
+ goto out;
+
+ if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
+ ipv4_update_pmtu(skb, dev_net(skb->dev), info,
+ t->dev->ifindex, 0, IPPROTO_IPIP, 0);
+ err = 0;
+ goto out;
+ }
+
+ if (t->parms.iph.daddr == 0)
goto out;
err = 0;
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 2c00e8bf684d1a3272401652c343b66fa69a3e54..340fcf29a966399c596dac530f27fb1fb3651974 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -371,6 +371,7 @@ void ping_err(struct sk_buff *skb, u32 info)
break;
case ICMP_DEST_UNREACH:
if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
+ ipv4_sk_update_pmtu(skb, sk, info);
if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
err = EMSGSIZE;
harderr = 1;
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 4032b818f3e41c13c5a0477a309eeea91ea3bf81..659ddfb109477112fd1216e82167ac2a22793fd3 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -216,6 +216,9 @@ static void raw_err(struct sock *sk, struct sk_buff *skb, u32 info)
int err = 0;
int harderr = 0;
+ if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED)
+ ipv4_sk_update_pmtu(skb, sk, info);
+
/* Report error on raw socket, if:
1. User requested ip_recverr.
2. Socket is connected (otherwise the error indication
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 655506af47cab540b910e1028837e970c7c93dc0..41df5297a412e9f2ad722f1f28846d609bbe4ea6 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1711,6 +1711,34 @@ static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
}
}
+void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu,
+ int oif, u32 mark, u8 protocol, int flow_flags)
+{
+ const struct iphdr *iph = (const struct iphdr *)skb->data;
+ struct flowi4 fl4;
+ struct rtable *rt;
+
+ flowi4_init_output(&fl4, oif, mark, RT_TOS(iph->tos), RT_SCOPE_UNIVERSE,
+ protocol, flow_flags | FLOWI_FLAG_PRECOW_METRICS,
+ iph->daddr, iph->saddr, 0, 0);
+ rt = __ip_route_output_key(net, &fl4);
+ if (!IS_ERR(rt)) {
+ ip_rt_update_pmtu(&rt->dst, mtu);
+ ip_rt_put(rt);
+ }
+}
+EXPORT_SYMBOL_GPL(ipv4_update_pmtu);
+
+void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
+{
+ const struct inet_sock *inet = inet_sk(sk);
+
+ return ipv4_update_pmtu(skb, sock_net(sk), mtu,
+ sk->sk_bound_dev_if, sk->sk_mark,
+ inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
+ inet_sk_flowi_flags(sk));
+}
+EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu);
static void ipv4_validate_peer(struct rtable *rt)
{
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index eaca73644e7965e5405b6e61f362a3be3e0d2e2f..db017efb76ea0b2fdd8a2ee975c955bda403a4d1 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -615,6 +615,7 @@ void __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable)
break;
case ICMP_DEST_UNREACH:
if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
+ ipv4_sk_update_pmtu(skb, sk, info);
if (inet->pmtudisc != IP_PMTUDISC_DONT) {
err = EMSGSIZE;
harderr = 1;
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 60415711563f36ffc21a4ebed82349751c62bae4..49aea94c9be3fcc9a898a734e28a54ccd6d49258 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -527,9 +527,6 @@ static int ipip6_err(struct sk_buff *skb, u32 info)
case ICMP_PORT_UNREACH:
/* Impossible event. */
return 0;
- case ICMP_FRAG_NEEDED:
- /* Soft state for pmtu is maintained by IP core. */
- return 0;
default:
/* All others are translated to HOST_UNREACH.
rfc2003 contains "deep thoughts" about NET_UNREACH,
@@ -551,7 +548,17 @@ static int ipip6_err(struct sk_buff *skb, u32 info)
skb->dev,
iph->daddr,
iph->saddr);
- if (t == NULL || t->parms.iph.daddr == 0)
+ if (t == NULL)
+ goto out;
+
+ if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
+ ipv4_update_pmtu(skb, dev_net(skb->dev), info,
+ t->dev->ifindex, 0, IPPROTO_IPV6, 0);
+ err = 0;
+ goto out;
+ }
+
+ if (t->parms.iph.daddr == 0)
goto out;
err = 0;