3 files changed, 43 insertions, 26 deletions

diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index 08ccd344de7..ae40ed1ba56 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -438,25 +438,27 @@ static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
 		goto tx_error;
 	}
 
-	if (tiph->frag_off)
+	df |= old_iph->frag_off & htons(IP_DF);
+
+	if (df) {
 		mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
-	else
-		mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
 
-	if (mtu < 68) {
-		stats->collisions++;
-		ip_rt_put(rt);
-		goto tx_error;
-	}
-	if (skb_dst(skb))
-		skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
+		if (mtu < 68) {
+			stats->collisions++;
+			ip_rt_put(rt);
+			goto tx_error;
+		}
 
-	df |= (old_iph->frag_off&htons(IP_DF));
+		if (skb_dst(skb))
+			skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
 
-	if ((old_iph->frag_off&htons(IP_DF)) && mtu < ntohs(old_iph->tot_len)) {
-		icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
-		ip_rt_put(rt);
-		goto tx_error;
+		if ((old_iph->frag_off & htons(IP_DF)) &&
+		    mtu < ntohs(old_iph->tot_len)) {
+			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
+				  htonl(mtu));
+			ip_rt_put(rt);
+			goto tx_error;
+		}
 	}
 
 	if (tunnel->err_count > 0) {
diff --git a/net/ipv4/netfilter/nf_nat_core.c b/net/ipv4/netfilter/nf_nat_core.c
index 68afc6ecd34..fe1a64479dd 100644
--- a/net/ipv4/netfilter/nf_nat_core.c
+++ b/net/ipv4/netfilter/nf_nat_core.c
@@ -750,6 +750,8 @@ static int __init nf_nat_init(void)
 	BUG_ON(nfnetlink_parse_nat_setup_hook != NULL);
 	rcu_assign_pointer(nfnetlink_parse_nat_setup_hook,
 			   nfnetlink_parse_nat_setup);
+	BUG_ON(nf_ct_nat_offset != NULL);
+	rcu_assign_pointer(nf_ct_nat_offset, nf_nat_get_offset);
 	return 0;
 
  cleanup_extend:
@@ -764,6 +766,7 @@ static void __exit nf_nat_cleanup(void)
 	nf_ct_extend_unregister(&nat_extend);
 	rcu_assign_pointer(nf_nat_seq_adjust_hook, NULL);
 	rcu_assign_pointer(nfnetlink_parse_nat_setup_hook, NULL);
+	rcu_assign_pointer(nf_ct_nat_offset, NULL);
 	synchronize_net();
 }
 
diff --git a/net/ipv4/netfilter/nf_nat_helper.c b/net/ipv4/netfilter/nf_nat_helper.c
index 09172a65d9b..f9520fa3aba 100644
--- a/net/ipv4/netfilter/nf_nat_helper.c
+++ b/net/ipv4/netfilter/nf_nat_helper.c
@@ -73,6 +73,28 @@ adjust_tcp_sequence(u32 seq,
 	DUMP_OFFSET(this_way);
 }
 
+/* Get the offset value, for conntrack */
+s16 nf_nat_get_offset(const struct nf_conn *ct,
+		      enum ip_conntrack_dir dir,
+		      u32 seq)
+{
+	struct nf_conn_nat *nat = nfct_nat(ct);
+	struct nf_nat_seq *this_way;
+	s16 offset;
+
+	if (!nat)
+		return 0;
+
+	this_way = &nat->seq[dir];
+	spin_lock_bh(&nf_nat_seqofs_lock);
+	offset = after(seq, this_way->correction_pos)
+		 ? this_way->offset_after : this_way->offset_before;
+	spin_unlock_bh(&nf_nat_seqofs_lock);
+
+	return offset;
+}
+EXPORT_SYMBOL_GPL(nf_nat_get_offset);
+
 /* Frobs data inside this packet, which is linear. */
 static void mangle_contents(struct sk_buff *skb,
 			    unsigned int dataoff,
@@ -189,11 +211,6 @@ nf_nat_mangle_tcp_packet(struct sk_buff *skb,
 		adjust_tcp_sequence(ntohl(tcph->seq),
 				    (int)rep_len - (int)match_len,
 				    ct, ctinfo);
-		/* Tell TCP window tracking about seq change */
-		nf_conntrack_tcp_update(skb, ip_hdrlen(skb),
-					ct, CTINFO2DIR(ctinfo),
-					(int)rep_len - (int)match_len);
-
 		nf_conntrack_event_cache(IPCT_NATSEQADJ, ct);
 	}
 	return 1;
@@ -415,12 +432,7 @@ nf_nat_seq_adjust(struct sk_buff *skb,
 	tcph->seq = newseq;
 	tcph->ack_seq = newack;
 
-	if (!nf_nat_sack_adjust(skb, tcph, ct, ctinfo))
-		return 0;
-
-	nf_conntrack_tcp_update(skb, ip_hdrlen(skb), ct, dir, seqoff);
-
-	return 1;
+	return nf_nat_sack_adjust(skb, tcph, ct, ctinfo);
 }
 
 /* Setup NAT on this expected conntrack so it follows master. */