netfilter: Add the missed return value check of register_netdevice_notifier

There are some codes of netfilter module which did not check the return
value of register_netdevice_notifier. Add the checks now.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/nf_tables_netdev.c

@@ -151,12 +151,20 @@ static int __init nf_tables_netdev_init(void)
 
 	nft_register_chain_type(&nft_filter_chain_netdev);
 	ret = register_pernet_subsys(&nf_tables_netdev_net_ops);
-	if (ret < 0) {
+	if (ret)
+		goto err1;
+
+	ret = register_netdevice_notifier(&nf_tables_netdev_notifier);
+	if (ret)
+		goto err2;
+
+	return 0;
+
+err2:
+	unregister_pernet_subsys(&nf_tables_netdev_net_ops);
+err1:
 	nft_unregister_chain_type(&nft_filter_chain_netdev);
 	return ret;
-	}
-	register_netdevice_notifier(&nf_tables_netdev_notifier);
-	return 0;
 }
 
 static void __exit nf_tables_netdev_exit(void)

net/netfilter/nfnetlink_queue.c

@@ -1522,9 +1522,16 @@ static int __init nfnetlink_queue_init(void)
 		goto cleanup_netlink_notifier;
 	}
 
-	register_netdevice_notifier(&nfqnl_dev_notifier);
+	status = register_netdevice_notifier(&nfqnl_dev_notifier);
+	if (status < 0) {
+		pr_err("nf_queue: failed to register netdevice notifier\n");
+		goto cleanup_netlink_subsys;
+	}
+
 	return status;
 
+cleanup_netlink_subsys:
+	nfnetlink_subsys_unregister(&nfqnl_subsys);
 cleanup_netlink_notifier:
 	netlink_unregister_notifier(&nfqnl_rtnl_notifier);
 	unregister_pernet_subsys(&nfnl_queue_net_ops);

net/netfilter/xt_TEE.c

@@ -89,6 +89,8 @@ static int tee_tg_check(const struct xt_tgchk_param *par)
 		return -EINVAL;
 
 	if (info->oif[0]) {
+		int ret;
+
 		if (info->oif[sizeof(info->oif)-1] != '\0')
 			return -EINVAL;
 
@@ -101,7 +103,11 @@ static int tee_tg_check(const struct xt_tgchk_param *par)
 		priv->notifier.notifier_call = tee_netdev_event;
 		info->priv    = priv;
 
-		register_netdevice_notifier(&priv->notifier);
+		ret = register_netdevice_notifier(&priv->notifier);
+		if (ret) {
+			kfree(priv);
+			return ret;
+		}
 	} else
 		info->priv = NULL;