diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/ip_forward.c | 7 | ||||
| -rw-r--r-- | net/ipv4/ip_output.c | 8 | ||||
| -rw-r--r-- | net/ipv4/route.c | 3 | ||||
| -rw-r--r-- | net/ipv4/sysctl_net_ipv4.c | 7 |
4 files changed, 17 insertions, 8 deletions
diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c index 694de3b7aebf..e9f1217a8afd 100644 --- a/net/ipv4/ip_forward.c +++ b/net/ipv4/ip_forward.c @@ -54,6 +54,7 @@ static int ip_forward_finish(struct sk_buff *skb) int ip_forward(struct sk_buff *skb) { + u32 mtu; struct iphdr *iph; /* Our header */ struct rtable *rt; /* Route we use */ struct ip_options *opt = &(IPCB(skb)->opt); @@ -88,11 +89,13 @@ int ip_forward(struct sk_buff *skb) if (opt->is_strictroute && rt->rt_uses_gateway) goto sr_failed; - if (unlikely(skb->len > dst_mtu(&rt->dst) && !skb_is_gso(skb) && + IPCB(skb)->flags |= IPSKB_FORWARDED; + mtu = ip_dst_mtu_maybe_forward(&rt->dst, true); + if (unlikely(skb->len > mtu && !skb_is_gso(skb) && (ip_hdr(skb)->frag_off & htons(IP_DF))) && !skb->local_df) { IP_INC_STATS(dev_net(rt->dst.dev), IPSTATS_MIB_FRAGFAILS); icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, - htonl(dst_mtu(&rt->dst))); + htonl(mtu)); goto drop; } diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index df184616493f..9a78804cfe9c 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -449,6 +449,7 @@ int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) __be16 not_last_frag; struct rtable *rt = skb_rtable(skb); int err = 0; + bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED; dev = rt->dst.dev; @@ -458,12 +459,13 @@ int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) iph = ip_hdr(skb); + mtu = ip_dst_mtu_maybe_forward(&rt->dst, forwarding); if (unlikely(((iph->frag_off & htons(IP_DF)) && !skb->local_df) || (IPCB(skb)->frag_max_size && - IPCB(skb)->frag_max_size > dst_mtu(&rt->dst)))) { + IPCB(skb)->frag_max_size > mtu))) { IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS); icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, - htonl(ip_skb_dst_mtu(skb))); + htonl(mtu)); kfree_skb(skb); return -EMSGSIZE; } @@ -473,7 +475,7 @@ int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) */ hlen = iph->ihl * 4; - mtu = dst_mtu(&rt->dst) - hlen; /* Size of data space */ + mtu = mtu - hlen; /* Size of data space */ #ifdef CONFIG_BRIDGE_NETFILTER if (skb->nf_bridge) mtu -= nf_bridge_mtu_reduction(skb); diff --git a/net/ipv4/route.c b/net/ipv4/route.c index f8da28278014..25071b48921c 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -112,9 +112,6 @@ #define RT_FL_TOS(oldflp4) \ ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK)) -/* IPv4 datagram length is stored into 16bit field (tot_len) */ -#define IP_MAX_MTU 0xFFFF - #define RT_GC_TIMEOUT (300*HZ) static int ip_rt_max_size; diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index 1d2480ac2bb6..44eba052b43d 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -831,6 +831,13 @@ static struct ctl_table ipv4_net_table[] = { .mode = 0644, .proc_handler = proc_dointvec }, + { + .procname = "ip_forward_use_pmtu", + .data = &init_net.ipv4.sysctl_ip_fwd_use_pmtu, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, { } }; |