netfilter: nf_tables: use net_generic infra for transaction data

This moves all nf_tables pernet data from struct net to a net_generic
extension, with the exception of the gencursor.

The latter is used in the data path and also outside of the nf_tables
core. All others are only used from the configuration plane.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

include/net/netfilter/nf_tables.h

@@ -1567,4 +1567,15 @@ __printf(2, 3) int nft_request_module(struct net *net, const char *fmt, ...);
 #else
 static inline int nft_request_module(struct net *net, const char *fmt, ...) { return -ENOENT; }
 #endif
+
+struct nftables_pernet {
+	struct list_head	tables;
+	struct list_head	commit_list;
+	struct list_head	module_list;
+	struct list_head	notify_list;
+	struct mutex		commit_mutex;
+	unsigned int		base_seq;
+	u8			validate_state;
+};
+
 #endif /* _NET_NF_TABLES_H */

net/netfilter/nf_tables_offload.c

@@ -7,6 +7,8 @@
 #include <net/netfilter/nf_tables_offload.h>
 #include <net/pkt_cls.h>
 
+extern unsigned int nf_tables_net_id;
+
 static struct nft_flow_rule *nft_flow_rule_alloc(int num_actions)
 {
 	struct nft_flow_rule *flow;
@@ -307,16 +309,18 @@ static void nft_indr_block_cleanup(struct flow_block_cb *block_cb)
 	struct nft_base_chain *basechain = block_cb->indr.data;
 	struct net_device *dev = block_cb->indr.dev;
 	struct netlink_ext_ack extack = {};
+	struct nftables_pernet *nft_net;
 	struct net *net = dev_net(dev);
 	struct flow_block_offload bo;
 
 	nft_flow_block_offload_init(&bo, dev_net(dev), FLOW_BLOCK_UNBIND,
 				    basechain, &extack);
-	mutex_lock(&net->nft.commit_mutex);
+	nft_net = net_generic(net, nf_tables_net_id);
+	mutex_lock(&nft_net->commit_mutex);
 	list_del(&block_cb->driver_list);
 	list_move(&block_cb->list, &bo.cb_list);
 	nft_flow_offload_unbind(&bo, basechain);
-	mutex_unlock(&net->nft.commit_mutex);
+	mutex_unlock(&nft_net->commit_mutex);
 }
 
 static int nft_indr_block_offload_cmd(struct nft_base_chain *basechain,
@@ -412,9 +416,10 @@ static int nft_flow_offload_chain(struct nft_chain *chain, u8 *ppolicy,
 static void nft_flow_rule_offload_abort(struct net *net,
 					struct nft_trans *trans)
 {
+	struct nftables_pernet *nft_net = net_generic(net, nf_tables_net_id);
 	int err = 0;
 
-	list_for_each_entry_continue_reverse(trans, &net->nft.commit_list, list) {
+	list_for_each_entry_continue_reverse(trans, &nft_net->commit_list, list) {
 		if (trans->ctx.family != NFPROTO_NETDEV)
 			continue;
 
@@ -460,11 +465,12 @@ static void nft_flow_rule_offload_abort(struct net *net,
 
 int nft_flow_rule_offload_commit(struct net *net)
 {
+	struct nftables_pernet *nft_net = net_generic(net, nf_tables_net_id);
 	struct nft_trans *trans;
 	int err = 0;
 	u8 policy;
 
-	list_for_each_entry(trans, &net->nft.commit_list, list) {
+	list_for_each_entry(trans, &nft_net->commit_list, list) {
 		if (trans->ctx.family != NFPROTO_NETDEV)
 			continue;
 
@@ -516,7 +522,7 @@ int nft_flow_rule_offload_commit(struct net *net)
 		}
 	}
 
-	list_for_each_entry(trans, &net->nft.commit_list, list) {
+	list_for_each_entry(trans, &nft_net->commit_list, list) {
 		if (trans->ctx.family != NFPROTO_NETDEV)
 			continue;
 
@@ -536,15 +542,15 @@ int nft_flow_rule_offload_commit(struct net *net)
 	return err;
 }
 
-static struct nft_chain *__nft_offload_get_chain(struct net_device *dev)
+static struct nft_chain *__nft_offload_get_chain(const struct nftables_pernet *nft_net,
+						 struct net_device *dev)
 {
 	struct nft_base_chain *basechain;
-	struct net *net = dev_net(dev);
 	struct nft_hook *hook, *found;
 	const struct nft_table *table;
 	struct nft_chain *chain;
 
-	list_for_each_entry(table, &net->nft.tables, list) {
+	list_for_each_entry(table, &nft_net->tables, list) {
 		if (table->family != NFPROTO_NETDEV)
 			continue;
 
@@ -576,19 +582,21 @@ static int nft_offload_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;
 	struct net *net = dev_net(dev);
 	struct nft_chain *chain;
 
 	if (event != NETDEV_UNREGISTER)
 		return NOTIFY_DONE;
 
-	mutex_lock(&net->nft.commit_mutex);
-	chain = __nft_offload_get_chain(dev);
+	nft_net = net_generic(net, nf_tables_net_id);
+	mutex_lock(&nft_net->commit_mutex);
+	chain = __nft_offload_get_chain(nft_net, dev);
 	if (chain)
 		nft_flow_block_chain(nft_base_chain(chain), dev,
 				     FLOW_BLOCK_UNBIND);
 
-	mutex_unlock(&net->nft.commit_mutex);
+	mutex_unlock(&nft_net->commit_mutex);
 
 	return NOTIFY_DONE;
 }

net/netfilter/nft_chain_filter.c

@@ -2,6 +2,7 @@
 #include <linux/kernel.h>
 #include <linux/netdevice.h>
 #include <net/net_namespace.h>
+#include <net/netns/generic.h>
 #include <net/netfilter/nf_tables.h>
 #include <linux/netfilter_ipv4.h>
 #include <linux/netfilter_ipv6.h>
@@ -10,6 +11,8 @@
 #include <net/netfilter/nf_tables_ipv4.h>
 #include <net/netfilter/nf_tables_ipv6.h>
 
+extern unsigned int nf_tables_net_id;
+
 #ifdef CONFIG_NF_TABLES_IPV4
 static unsigned int nft_do_chain_ipv4(void *priv,
 				      struct sk_buff *skb,
@@ -355,6 +358,7 @@ 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;
 	struct nft_table *table;
 	struct nft_chain *chain, *nr;
 	struct nft_ctx ctx = {
@@ -365,8 +369,9 @@ static int nf_tables_netdev_event(struct notifier_block *this,
 	    event != NETDEV_CHANGENAME)
 		return NOTIFY_DONE;
 
-	mutex_lock(&ctx.net->nft.commit_mutex);
-	list_for_each_entry(table, &ctx.net->nft.tables, list) {
+	nft_net = net_generic(ctx.net, nf_tables_net_id);
+	mutex_lock(&nft_net->commit_mutex);
+	list_for_each_entry(table, &nft_net->tables, list) {
 		if (table->family != NFPROTO_NETDEV)
 			continue;
 
@@ -380,7 +385,7 @@ static int nf_tables_netdev_event(struct notifier_block *this,
 			nft_netdev_event(event, dev, &ctx);
 		}
 	}
-	mutex_unlock(&ctx.net->nft.commit_mutex);
+	mutex_unlock(&nft_net->commit_mutex);
 
 	return NOTIFY_DONE;
 }

net/netfilter/nft_dynset.c

@@ -11,6 +11,9 @@
 #include <linux/netfilter/nf_tables.h>
 #include <net/netfilter/nf_tables.h>
 #include <net/netfilter/nf_tables_core.h>
+#include <net/netns/generic.h>
+
+extern unsigned int nf_tables_net_id;
 
 struct nft_dynset {
 	struct nft_set			*set;
@@ -161,13 +164,14 @@ static int nft_dynset_init(const struct nft_ctx *ctx,
 			   const struct nft_expr *expr,
 			   const struct nlattr * const tb[])
 {
+	struct nftables_pernet *nft_net = net_generic(ctx->net, nf_tables_net_id);
 	struct nft_dynset *priv = nft_expr_priv(expr);
 	u8 genmask = nft_genmask_next(ctx->net);
 	struct nft_set *set;
 	u64 timeout;
 	int err, i;
 
-	lockdep_assert_held(&ctx->net->nft.commit_mutex);
+	lockdep_assert_held(&nft_net->commit_mutex);
 
 	if (tb[NFTA_DYNSET_SET_NAME] == NULL ||
 	    tb[NFTA_DYNSET_OP] == NULL ||