[nf-next PATCH v3 11/16] netfilter: nf_tables: chain: Respect NETDEV_REGISTER events

[Phil Sutter <phil@nwl.cc>]

Hook into new devices if their name matches the hook spec.

Signed-off-by: Phil Sutter <phil@nwl.cc>
---
 net/netfilter/nft_chain_filter.c | 40 +++++++++++++++++++++++++-------
 1 file changed, 32 insertions(+), 8 deletions(-)

diff --git a/net/netfilter/nft_chain_filter.c b/net/netfilter/nft_chain_filter.c
index 2507e3beac5c..ec44c27a9d91 100644
--- a/net/netfilter/nft_chain_filter.c
+++ b/net/netfilter/nft_chain_filter.c
@@ -326,14 +326,37 @@ static void nft_netdev_event(unsigned long event, struct net_device *dev,
 	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 (!(ctx->chain->table->flags & NFT_TABLE_F_DORMANT))
-			nf_unregister_net_hook(ctx->net, ops);
-		list_del(&ops->list);
-		kfree(ops);
+			if (!(ctx->chain->table->flags & NFT_TABLE_F_DORMANT))
+				nf_unregister_net_hook(ctx->net, ops);
+			list_del(&ops->list);
+			kfree(ops);
+			break;
+		case NETDEV_REGISTER:
+			if (strcmp(hook->ifname, dev->name))
+				continue;
+			ops = kzalloc(sizeof(struct nf_hook_ops),
+				      GFP_KERNEL_ACCOUNT);
+			if (ops) {
+				memcpy(ops, &basechain->ops, sizeof(*ops));
+				ops->dev = dev;
+			}
+			if (ops &&
+			    (ctx->chain->table->flags & NFT_TABLE_F_DORMANT ||
+			     !nf_register_net_hook(dev_net(dev), ops))) {
+				list_add_tail(&ops->list, &hook->ops_list);
+				break;
+			}
+			printk(KERN_ERR "chain %s: Can't hook into device %s\n",
+			       ctx->chain->name, dev->name);
+			kfree(ops);
+			continue;
+		}
 	}
 }
 
@@ -349,7 +372,8 @@ static int nf_tables_netdev_event(struct notifier_block *this,
 		.net	= dev_net(dev),
 	};
 
-	if (event != NETDEV_UNREGISTER)
+	if (event != NETDEV_REGISTER &&
+	    event != NETDEV_UNREGISTER)
 		return NOTIFY_DONE;
 
 	nft_net = nft_pernet(ctx.net);
-- 
2.43.0