[PATCH v2 5/7] netfilter: nf_tables: Correctly handle NETDEV_RENAME events

[Phil Sutter <phil@nwl.cc>]

Treat a netdev rename like removal and recreation with a different name.
In theory, one could leave hooks in place which still cover the new
name, but this is both unlikely and needlessly complicates the
code.

Signed-off-by: Phil Sutter <phil@nwl.cc>
---
 net/netfilter/nf_tables_api.c    | 10 +++++++---
 net/netfilter/nft_chain_filter.c |  9 ++++++---
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index b19f40874c48..b3a5a2878459 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -9247,9 +9247,13 @@ static int nf_tables_flowtable_event(struct notifier_block *this,
 	struct nft_table *table;
 	struct net *net;
 
-	if (event != NETDEV_UNREGISTER &&
-	    event != NETDEV_REGISTER)
-		return 0;
+	if (event == NETDEV_CHANGENAME) {
+		nf_tables_flowtable_event(this, NETDEV_UNREGISTER, ptr);
+		event = NETDEV_REGISTER;
+	} else if (event != NETDEV_UNREGISTER &&
+		   event != NETDEV_REGISTER) {
+		return NOTIFY_DONE;
+	}
 
 	net = dev_net(dev);
 	nft_net = nft_pernet(net);
diff --git a/net/netfilter/nft_chain_filter.c b/net/netfilter/nft_chain_filter.c
index b2147f8be60c..cc0cf47503f4 100644
--- a/net/netfilter/nft_chain_filter.c
+++ b/net/netfilter/nft_chain_filter.c
@@ -379,10 +379,13 @@ static int nf_tables_netdev_event(struct notifier_block *this,
 		.net	= dev_net(dev),
 	};
 
-	if (event != NETDEV_UNREGISTER &&
-	    event != NETDEV_REGISTER &&
-	    event != NETDEV_CHANGENAME)
+	if (event == NETDEV_CHANGENAME) {
+		nf_tables_netdev_event(this, NETDEV_UNREGISTER, ptr);
+		event = NETDEV_REGISTER;
+	} else if (event != NETDEV_UNREGISTER &&
+		   event != NETDEV_REGISTER) {
 		return NOTIFY_DONE;
+	}
 
 	nft_net = nft_pernet(ctx.net);
 	mutex_lock(&nft_net->commit_mutex);
-- 
2.43.0