ipv6: add net device refcount tracker to struct ip6_tnl

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

include/net/ip6_tunnel.h

@@ -46,6 +46,7 @@ struct __ip6_tnl_parm {
 struct ip6_tnl {
 	struct ip6_tnl __rcu *next;	/* next tunnel in list */
 	struct net_device *dev;	/* virtual device associated with tunnel */
+	netdevice_tracker dev_tracker;
 	struct net *net;	/* netns for packet i/o */
 	struct __ip6_tnl_parm parms;	/* tunnel configuration parameters */
 	struct flowi fl;	/* flowi template for xmit */

net/ipv6/ip6_gre.c

@@ -403,7 +403,7 @@ static void ip6erspan_tunnel_uninit(struct net_device *dev)
 	ip6erspan_tunnel_unlink_md(ign, t);
 	ip6gre_tunnel_unlink(ign, t);
 	dst_cache_reset(&t->dst_cache);
-	dev_put(dev);
+	dev_put_track(dev, &t->dev_tracker);
 }
 
 static void ip6gre_tunnel_uninit(struct net_device *dev)
@@ -416,7 +416,7 @@ static void ip6gre_tunnel_uninit(struct net_device *dev)
 	if (ign->fb_tunnel_dev == dev)
 		WRITE_ONCE(ign->fb_tunnel_dev, NULL);
 	dst_cache_reset(&t->dst_cache);
-	dev_put(dev);
+	dev_put_track(dev, &t->dev_tracker);
 }
 
 
@@ -1496,7 +1496,7 @@ static int ip6gre_tunnel_init_common(struct net_device *dev)
 	}
 	ip6gre_tnl_init_features(dev);
 
-	dev_hold(dev);
+	dev_hold_track(dev, &tunnel->dev_tracker, GFP_KERNEL);
 	return 0;
 
 cleanup_dst_cache_init:
@@ -1888,7 +1888,7 @@ static int ip6erspan_tap_init(struct net_device *dev)
 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
 	ip6erspan_tnl_link_config(tunnel, 1);
 
-	dev_hold(dev);
+	dev_hold_track(dev, &tunnel->dev_tracker, GFP_KERNEL);
 	return 0;
 
 cleanup_dst_cache_init:

net/ipv6/ip6_tunnel.c

@@ -383,7 +383,7 @@ ip6_tnl_dev_uninit(struct net_device *dev)
 	else
 		ip6_tnl_unlink(ip6n, t);
 	dst_cache_reset(&t->dst_cache);
-	dev_put(dev);
+	dev_put_track(dev, &t->dev_tracker);
 }
 
 /**
@@ -1883,7 +1883,7 @@ ip6_tnl_dev_init_gen(struct net_device *dev)
 	dev->min_mtu = ETH_MIN_MTU;
 	dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len;
 
-	dev_hold(dev);
+	dev_hold_track(dev, &t->dev_tracker, GFP_KERNEL);
 	return 0;
 
 destroy_dst:

net/ipv6/ip6_vti.c

@@ -293,7 +293,7 @@ static void vti6_dev_uninit(struct net_device *dev)
 		RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 	else
 		vti6_tnl_unlink(ip6n, t);
-	dev_put(dev);
+	dev_put_track(dev, &t->dev_tracker);
 }
 
 static int vti6_input_proto(struct sk_buff *skb, int nexthdr, __be32 spi,
@@ -934,7 +934,7 @@ static inline int vti6_dev_init_gen(struct net_device *dev)
 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 	if (!dev->tstats)
 		return -ENOMEM;
-	dev_hold(dev);
+	dev_hold_track(dev, &t->dev_tracker, GFP_KERNEL);
 	return 0;
 }