--- zzzz-none-000/linux-4.4.271/net/ipv6/sit.c	2021-06-03 06:22:09.000000000 +0000
+++ hawkeye-5590-750/linux-4.4.271/net/ipv6/sit.c	2023-04-19 10:22:30.000000000 +0000
@@ -87,6 +87,21 @@
 	struct net_device *fb_tunnel_dev;
 };
 
+void ipip6_update_offload_stats(struct net_device *dev, void *ptr)
+{
+	struct pcpu_sw_netstats *tstats = per_cpu_ptr(dev->tstats, 0);
+	const struct pcpu_sw_netstats *offload_stats =
+					(struct pcpu_sw_netstats *)ptr;
+
+	u64_stats_update_begin(&tstats->syncp);
+	tstats->tx_packets += offload_stats->tx_packets;
+	tstats->tx_bytes   += offload_stats->tx_bytes;
+	tstats->rx_packets += offload_stats->rx_packets;
+	tstats->rx_bytes   += offload_stats->rx_bytes;
+	u64_stats_update_end(&tstats->syncp);
+}
+EXPORT_SYMBOL(ipip6_update_offload_stats);
+
 /*
  * Must be invoked with rcu_read_lock
  */
@@ -713,6 +728,8 @@
 		tstats->rx_bytes += skb->len;
 		u64_stats_update_end(&tstats->syncp);
 
+		/* Reset the skb_iif to Tunnels interface index */
+		skb->skb_iif = tunnel->dev->ifindex;
 		netif_rx(skb);
 
 		return 0;
@@ -989,6 +1006,8 @@
 
 	skb_set_inner_ipproto(skb, IPPROTO_IPV6);
 
+	/* Reset the skb_iif to Tunnels interface index */
+	skb->skb_iif = tunnel->dev->ifindex;
 	err = iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr,
 			    protocol, tos, ttl, df,
 			    !net_eq(tunnel->net, dev_net(dev)));