netfilter: nf_tables: destroy basechain and rules on netdevice removal

If the netdevice is destroyed, the resources that are attached should
be released too as they belong to the device that is now gone.

Suggested-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 25 insertions, 6 deletions

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 852273110275..5729844e1d46 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -131,8 +131,8 @@ static void nft_trans_destroy(struct nft_trans *trans)
 	kfree(trans);
 }
 
-int nft_register_basechain(struct nft_base_chain *basechain,
-			   unsigned int hook_nops)
+static int nft_register_basechain(struct nft_base_chain *basechain,
+				  unsigned int hook_nops)
 {
 	struct net *net = read_pnet(&basechain->pnet);
 
@@ -141,10 +141,9 @@ int nft_register_basechain(struct nft_base_chain *basechain,
 
 	return nf_register_net_hooks(net, basechain->ops, hook_nops);
 }
-EXPORT_SYMBOL_GPL(nft_register_basechain);
 
-void nft_unregister_basechain(struct nft_base_chain *basechain,
-			      unsigned int hook_nops)
+static void nft_unregister_basechain(struct nft_base_chain *basechain,
+				     unsigned int hook_nops)
 {
 	struct net *net = read_pnet(&basechain->pnet);
 
@@ -153,7 +152,6 @@ void nft_unregister_basechain(struct nft_base_chain *basechain,
 
 	nf_unregister_net_hooks(net, basechain->ops, hook_nops);
 }
-EXPORT_SYMBOL_GPL(nft_unregister_basechain);
 
 static int nf_tables_register_hooks(const struct nft_table *table,
 				    struct nft_chain *chain,
@@ -4590,6 +4588,27 @@ static int __net_init nf_tables_init_net(struct net *net)
 	return 0;
 }
 
+int __nft_release_basechain(struct nft_ctx *ctx)
+{
+	struct nft_rule *rule, *nr;
+
+	BUG_ON(!(ctx->chain->flags & NFT_BASE_CHAIN));
+
+	nf_tables_unregister_hooks(ctx->chain->table, ctx->chain,
+				   ctx->afi->nops);
+	list_for_each_entry_safe(rule, nr, &ctx->chain->rules, list) {
+		list_del(&rule->list);
+		ctx->chain->use--;
+		nf_tables_rule_destroy(ctx, rule);
+	}
+	list_del(&ctx->chain->list);
+	ctx->table->use--;
+	nf_tables_chain_destroy(ctx->chain);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__nft_release_basechain);
+
 /* Called by nft_unregister_afinfo() from __net_exit path, nfnl_lock is held. */
 static void __nft_release_afinfo(struct net *net, struct nft_af_info *afi)
 {