[PATCH net-next 21/26] netfilter: nf_tables: Wrap netdev notifiers

[Pablo Neira Ayuso <pablo@netfilter.org>]

From: Phil Sutter <phil@nwl.cc>

Handling NETDEV_CHANGENAME events has to traverse all chains/flowtables
twice, prepare for this. No functional change intended.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nf_tables_api.c    | 34 ++++++++++++++++++----------
 net/netfilter/nft_chain_filter.c | 38 ++++++++++++++++++++------------
 2 files changed, 46 insertions(+), 26 deletions(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index f0f40aeccc0c..713ea0e48772 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -9736,13 +9736,28 @@ static int nft_flowtable_event(unsigned long event, struct net_device *dev,
 	return 0;
 }
 
+static int __nf_tables_flowtable_event(unsigned long event,
+				       struct net_device *dev)
+{
+	struct nftables_pernet *nft_net = nft_pernet(dev_net(dev));
+	struct nft_flowtable *flowtable;
+	struct nft_table *table;
+
+	list_for_each_entry(table, &nft_net->tables, list) {
+		list_for_each_entry(flowtable, &table->flowtables, list) {
+			if (nft_flowtable_event(event, dev, flowtable))
+				return 1;
+		}
+	}
+	return 0;
+}
+
 static int nf_tables_flowtable_event(struct notifier_block *this,
 				     unsigned long event, void *ptr)
 {
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
-	struct nft_flowtable *flowtable;
 	struct nftables_pernet *nft_net;
-	struct nft_table *table;
+	int ret = NOTIFY_DONE;
 	struct net *net;
 
 	if (event != NETDEV_REGISTER &&
@@ -9752,17 +9767,12 @@ static int nf_tables_flowtable_event(struct notifier_block *this,
 	net = dev_net(dev);
 	nft_net = nft_pernet(net);
 	mutex_lock(&nft_net->commit_mutex);
-	list_for_each_entry(table, &nft_net->tables, list) {
-		list_for_each_entry(flowtable, &table->flowtables, list) {
-			if (nft_flowtable_event(event, dev, flowtable)) {
-				mutex_unlock(&nft_net->commit_mutex);
-				return NOTIFY_BAD;
-			}
-		}
-	}
-	mutex_unlock(&nft_net->commit_mutex);
 
-	return NOTIFY_DONE;
+	if (__nf_tables_flowtable_event(event, dev))
+		ret = NOTIFY_BAD;
+
+	mutex_unlock(&nft_net->commit_mutex);
+	return ret;
 }
 
 static struct notifier_block nf_tables_flowtable_notifier = {
diff --git a/net/netfilter/nft_chain_filter.c b/net/netfilter/nft_chain_filter.c
index 58000b3893eb..7795dff13408 100644
--- a/net/netfilter/nft_chain_filter.c
+++ b/net/netfilter/nft_chain_filter.c
@@ -363,21 +363,14 @@ static int nft_netdev_event(unsigned long event, struct net_device *dev,
 	return 0;
 }
 
-static int nf_tables_netdev_event(struct notifier_block *this,
-				  unsigned long event, void *ptr)
+static int __nf_tables_netdev_event(unsigned long event, struct net_device *dev)
 {
-	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct nft_base_chain *basechain;
 	struct nftables_pernet *nft_net;
 	struct nft_chain *chain;
 	struct nft_table *table;
 
-	if (event != NETDEV_REGISTER &&
-	    event != NETDEV_UNREGISTER)
-		return NOTIFY_DONE;
-
 	nft_net = nft_pernet(dev_net(dev));
-	mutex_lock(&nft_net->commit_mutex);
 	list_for_each_entry(table, &nft_net->tables, list) {
 		if (table->family != NFPROTO_NETDEV &&
 		    table->family != NFPROTO_INET)
@@ -392,15 +385,32 @@ static int nf_tables_netdev_event(struct notifier_block *this,
 			    basechain->ops.hooknum != NF_INET_INGRESS)
 				continue;
 
-			if (nft_netdev_event(event, dev, basechain)) {
-				mutex_unlock(&nft_net->commit_mutex);
-				return NOTIFY_BAD;
-			}
+			if (nft_netdev_event(event, dev, basechain))
+				return 1;
 		}
 	}
-	mutex_unlock(&nft_net->commit_mutex);
+	return 0;
+}
+
+static int nf_tables_netdev_event(struct notifier_block *this,
+				  unsigned long event, void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	struct nftables_pernet *nft_net;
+	int ret = NOTIFY_DONE;
+
+	if (event != NETDEV_REGISTER &&
+	    event != NETDEV_UNREGISTER)
+		return NOTIFY_DONE;
 
-	return NOTIFY_DONE;
+	nft_net = nft_pernet(dev_net(dev));
+	mutex_lock(&nft_net->commit_mutex);
+
+	if (__nf_tables_netdev_event(event, dev))
+		ret = NOTIFY_BAD;
+
+	mutex_unlock(&nft_net->commit_mutex);
+	return ret;
 }
 
 static struct notifier_block nf_tables_netdev_notifier = {
-- 
2.30.2