--- zzzz-none-000/linux-4.4.271/drivers/net/tun.c	2021-06-03 06:22:09.000000000 +0000
+++ hawkeye-5590-750/linux-4.4.271/drivers/net/tun.c	2023-04-19 10:22:29.000000000 +0000
@@ -191,6 +191,8 @@
 	kgid_t			group;
 
 	struct net_device	*dev;
+	struct rtnl_link_stats64 stats;
+	spinlock_t stats64_lock;	/* protects statistics counters */
 	netdev_features_t	set_features;
 #define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \
 			  NETIF_F_TSO6|NETIF_F_UFO)
@@ -214,6 +216,8 @@
 	u32 flow_count;
 };
 
+static tun_get_offload_stats_t tun_get_offload_stats_cb;
+
 #ifdef CONFIG_TUN_VNET_CROSS_LE
 static inline bool tun_legacy_is_little_endian(struct tun_struct *tun)
 {
@@ -931,6 +935,28 @@
 
 	return (features & tun->set_features) | (features & ~TUN_USER_FEATURES);
 }
+
+struct rtnl_link_stats64 *tun_net_get_stats64(struct net_device *dev,
+					     struct rtnl_link_stats64 *stats)
+{
+	struct tun_struct *tun = netdev_priv(dev);
+
+	memset(stats, 0, sizeof(struct rtnl_link_stats64));
+	spin_lock(&tun->stats64_lock);
+
+	if (tun_get_offload_stats_cb)
+		tun_get_offload_stats_cb(dev, stats);
+
+	stats->rx_frame_errors += dev->stats.rx_frame_errors;
+	stats->rx_packets += dev->stats.rx_packets;
+	stats->rx_bytes += dev->stats.rx_bytes;
+	stats->tx_packets += dev->stats.tx_packets;
+	stats->tx_bytes += dev->stats.tx_bytes;
+
+	spin_unlock(&tun->stats64_lock);
+	return stats;
+}
+
 #ifdef CONFIG_NET_POLL_CONTROLLER
 static void tun_poll_controller(struct net_device *dev)
 {
@@ -956,6 +982,7 @@
 	.ndo_change_mtu		= tun_net_change_mtu,
 	.ndo_fix_features	= tun_net_fix_features,
 	.ndo_select_queue	= tun_select_queue,
+	.ndo_get_stats64        = tun_net_get_stats64,
 #ifdef CONFIG_NET_POLL_CONTROLLER
 	.ndo_poll_controller	= tun_poll_controller,
 #endif
@@ -1730,6 +1757,7 @@
 		dev->vlan_features = dev->features &
 				     ~(NETIF_F_HW_VLAN_CTAG_TX |
 				       NETIF_F_HW_VLAN_STAG_TX);
+		dev->priv_flags_ext |= IFF_EXT_TUN_TAP;
 
 		INIT_LIST_HEAD(&tun->disabled);
 		err = tun_attach(tun, file, false, false);
@@ -2423,7 +2451,6 @@
 	.get_ts_info	= ethtool_op_get_ts_info,
 };
 
-
 static int __init tun_init(void)
 {
 	int ret = 0;
@@ -2471,6 +2498,21 @@
 }
 EXPORT_SYMBOL_GPL(tun_get_socket);
 
+/* Register tun offload statistics callback */
+void tun_register_offload_stats_callback(tun_get_offload_stats_t stats_cb)
+{
+	BUG_ON(tun_get_offload_stats_cb);
+	rcu_assign_pointer(tun_get_offload_stats_cb, stats_cb);
+}
+EXPORT_SYMBOL(tun_register_offload_stats_callback);
+
+/* Unregister tun offload statistics callback */
+void tun_unregister_offload_stats_callback(void)
+{
+	rcu_assign_pointer(tun_get_offload_stats_cb, NULL);
+}
+EXPORT_SYMBOL(tun_unregister_offload_stats_callback);
+
 module_init(tun_init);
 module_exit(tun_cleanup);
 MODULE_DESCRIPTION(DRV_DESCRIPTION);