These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / net / ipv4 / ip_forward.c

diff --git a/kernel/net/ipv4/ip_forward.c b/kernel/net/ipv4/ip_forward.c
index 3674484..da0d7ce 100644 (file)
--- a/kernel/net/ipv4/ip_forward.c
+++ b/kernel/net/ipv4/ip_forward.c
@@ -39,17 +39,21 @@
 #include <net/route.h>
 #include <net/xfrm.h>
 
-static bool ip_may_fragment(const struct sk_buff *skb)
-{
-       return unlikely((ip_hdr(skb)->frag_off & htons(IP_DF)) == 0) ||
-               skb->ignore_df;
-}
-
 static bool ip_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu)
 {
        if (skb->len <= mtu)
                return false;
 
+       if (unlikely((ip_hdr(skb)->frag_off & htons(IP_DF)) == 0))
+               return false;
+
+       /* original fragment exceeds mtu and DF is set */
+       if (unlikely(IPCB(skb)->frag_max_size > mtu))
+               return true;
+
+       if (skb->ignore_df)
+               return false;
+
        if (skb_is_gso(skb) && skb_gso_network_seglen(skb) <= mtu)
                return false;
 
@@ -57,18 +61,18 @@ static bool ip_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu)
 }
 
 
-static int ip_forward_finish(struct sock *sk, struct sk_buff *skb)
+static int ip_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
        struct ip_options *opt  = &(IPCB(skb)->opt);
 
-       IP_INC_STATS_BH(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_OUTFORWDATAGRAMS);
-       IP_ADD_STATS_BH(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_OUTOCTETS, skb->len);
+       IP_INC_STATS_BH(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
+       IP_ADD_STATS_BH(net, IPSTATS_MIB_OUTOCTETS, skb->len);
 
        if (unlikely(opt->optlen))
                ip_forward_options(skb);
 
        skb_sender_cpu_clear(skb);
-       return dst_output_sk(sk, skb);
+       return dst_output(net, sk, skb);
 }
 
 int ip_forward(struct sk_buff *skb)
@@ -77,6 +81,7 @@ int ip_forward(struct sk_buff *skb)
        struct iphdr *iph;      /* Our header */
        struct rtable *rt;      /* Route we use */
        struct ip_options *opt  = &(IPCB(skb)->opt);
+       struct net *net;
 
        /* that should never happen */
        if (skb->pkt_type != PACKET_HOST)
@@ -95,6 +100,7 @@ int ip_forward(struct sk_buff *skb)
                return NET_RX_SUCCESS;
 
        skb_forward_csum(skb);
+       net = dev_net(skb->dev);
 
        /*
         *      According to the RFC, we must first decrease the TTL field. If
@@ -114,8 +120,8 @@ int ip_forward(struct sk_buff *skb)
 
        IPCB(skb)->flags |= IPSKB_FORWARDED;
        mtu = ip_dst_mtu_maybe_forward(&rt->dst, true);
-       if (!ip_may_fragment(skb) && ip_exceeds_mtu(skb, mtu)) {
-               IP_INC_STATS(dev_net(rt->dst.dev), IPSTATS_MIB_FRAGFAILS);
+       if (ip_exceeds_mtu(skb, mtu)) {
+               IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);
                icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
                          htonl(mtu));
                goto drop;
@@ -139,8 +145,9 @@ int ip_forward(struct sk_buff *skb)
 
        skb->priority = rt_tos2priority(iph->tos);
 
-       return NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD, NULL, skb,
-                      skb->dev, rt->dst.dev, ip_forward_finish);
+       return NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD,
+                      net, NULL, skb, skb->dev, rt->dst.dev,
+                      ip_forward_finish);
 
 sr_failed:
        /*
@@ -151,7 +158,7 @@ sr_failed:
 
 too_many_hops:
        /* Tell the sender its packet died... */
-       IP_INC_STATS_BH(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_INHDRERRORS);
+       IP_INC_STATS_BH(net, IPSTATS_MIB_INHDRERRORS);
        icmp_send(skb, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL, 0);
 drop:
        kfree_skb(skb);