netfilter: nf_tables: Prepare for handling NETDEV_REGISTER events

Put NETDEV_UNREGISTER handling code into a switch, no functional change
intended as the function is only called for that event yet.

Signed-off-by: Phil Sutter <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>

Author: Phil Sutter

net/netfilter/nf_tables_api.c

@@ -9696,14 +9696,19 @@ static void nft_flowtable_event(unsigned long event, struct net_device *dev,
 	struct nft_hook *hook;
 
 	list_for_each_entry(hook, &flowtable->hook_list, list) {
-		ops = nft_hook_find_ops(hook, dev);
-		if (!ops)
-			continue;
+		switch (event) {
+		case NETDEV_UNREGISTER:
+			ops = nft_hook_find_ops(hook, dev);
+			if (!ops)
+				continue;
 
-		/* flow_offload_netdev_event() cleans up entries for us. */
-		nft_unregister_flowtable_ops(dev_net(dev), flowtable, ops);
-		list_del_rcu(&ops->list);
-		kfree_rcu(ops, rcu);
+			/* flow_offload_netdev_event() cleans up entries for us. */
+			nft_unregister_flowtable_ops(dev_net(dev),
+						     flowtable, ops);
+			list_del_rcu(&ops->list);
+			kfree_rcu(ops, rcu);
+			break;
+		}
 		break;
 	}
 }

net/netfilter/nft_chain_filter.c

@@ -321,19 +321,24 @@ static const struct nft_chain_type nft_chain_filter_netdev = {
 static void nft_netdev_event(unsigned long event, struct net_device *dev,
 			     struct nft_base_chain *basechain)
 {
+	struct nft_table *table = basechain->chain.table;
 	struct nf_hook_ops *ops;
 	struct nft_hook *hook;
 
 	list_for_each_entry(hook, &basechain->hook_list, list) {
-		ops = nft_hook_find_ops(hook, dev);
-		if (!ops)
-			continue;
+		switch (event) {
+		case NETDEV_UNREGISTER:
+			ops = nft_hook_find_ops(hook, dev);
+			if (!ops)
+				continue;
 
-		if (!(basechain->chain.table->flags & NFT_TABLE_F_DORMANT))
-			nf_unregister_net_hook(dev_net(dev), ops);
+			if (!(table->flags & NFT_TABLE_F_DORMANT))
+				nf_unregister_net_hook(dev_net(dev), ops);
 
-		list_del_rcu(&ops->list);
-		kfree_rcu(ops, rcu);
+			list_del_rcu(&ops->list);
+			kfree_rcu(ops, rcu);
+			break;
+		}
 		break;
 	}
 }