From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Tue, 23 Mar 2021 00:56:27 +0100
Subject: [PATCH] netfilter: flowtable: refresh timeout after dst and
 writable checks

Refresh the timeout (and retry hardware offload) once the skbuff dst
is confirmed to be current and after the skbuff is made writable.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---

--- a/net/netfilter/nf_flow_table_ip.c
+++ b/net/netfilter/nf_flow_table_ip.c
@@ -246,8 +246,6 @@ nf_flow_offload_ip_hook(void *priv, stru
 	if (nf_flow_state_check(flow, iph->protocol, skb, thoff))
 		return NF_ACCEPT;
 
-	flow_offload_refresh(flow_table, flow);
-
 	if (!dst_check(&rt->dst, 0)) {
 		flow_offload_teardown(flow);
 		return NF_ACCEPT;
@@ -256,6 +254,8 @@ nf_flow_offload_ip_hook(void *priv, stru
 	if (skb_try_make_writable(skb, thoff + hdrsize))
 		return NF_DROP;
 
+	flow_offload_refresh(flow_table, flow);
+
 	iph = ip_hdr(skb);
 	nf_flow_nat_ip(flow, skb, thoff, dir, iph);
 
@@ -466,8 +466,6 @@ nf_flow_offload_ipv6_hook(void *priv, st
 				sizeof(*ip6h)))
 		return NF_ACCEPT;
 
-	flow_offload_refresh(flow_table, flow);
-
 	if (!dst_check(&rt->dst, 0)) {
 		flow_offload_teardown(flow);
 		return NF_ACCEPT;
@@ -476,6 +474,8 @@ nf_flow_offload_ipv6_hook(void *priv, st
 	if (skb_try_make_writable(skb, sizeof(*ip6h) + hdrsize))
 		return NF_DROP;
 
+	flow_offload_refresh(flow_table, flow);
+
 	ip6h = ipv6_hdr(skb);
 	nf_flow_nat_ipv6(flow, skb, dir, ip6h);