netfilter: ip6tables: Add a .pre_exit hook in all ip6table_foo.c.

Using new helpers ip6t_unregister_table_pre_exit() and
ip6t_unregister_table_exit().

Fixes: b9e69e127397 ("netfilter: xtables: don't hook tables by default")
Signed-off-by: David Wilder <[e-mail]>
Signed-off-by: Pablo Neira Ayuso <[e-mail]>

net/ipv6/netfilter/ip6table_filter.c

···
 	return 0;
 }
 
+static void __net_exit ip6table_filter_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_filter)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_filter,
+					       filter_ops);
+}
+
 static void __net_exit ip6table_filter_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_filter)
 		return;
-	ip6t_unregister_table(net, net->ipv6.ip6table_filter, filter_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_filter);
 	net->ipv6.ip6table_filter = NULL;
 }
 
 static struct pernet_operations ip6table_filter_net_ops = {
 	.init = ip6table_filter_net_init,
+	.pre_exit = ip6table_filter_net_pre_exit,
 	.exit = ip6table_filter_net_exit,
 };
 

net/ipv6/netfilter/ip6table_mangle.c

···
 	return ret;
 }
 
+static void __net_exit ip6table_mangle_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_mangle)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_mangle,
+					       mangle_ops);
+}
+
 static void __net_exit ip6table_mangle_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_mangle)
 		return;
 
-	ip6t_unregister_table(net, net->ipv6.ip6table_mangle, mangle_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_mangle);
 	net->ipv6.ip6table_mangle = NULL;
 }
 
 static struct pernet_operations ip6table_mangle_net_ops = {
+	.pre_exit = ip6table_mangle_net_pre_exit,
 	.exit = ip6table_mangle_net_exit,
 };
 

net/ipv6/netfilter/ip6table_nat.c

···
 	return ret;
 }
 
+static void __net_exit ip6table_nat_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_nat)
+		ip6t_nat_unregister_lookups(net);
+}
+
 static void __net_exit ip6table_nat_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_nat)
 		return;
-	ip6t_nat_unregister_lookups(net);
-	ip6t_unregister_table(net, net->ipv6.ip6table_nat, NULL);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_nat);
 	net->ipv6.ip6table_nat = NULL;
 }
 
 static struct pernet_operations ip6table_nat_net_ops = {
+	.pre_exit = ip6table_nat_net_pre_exit,
 	.exit	= ip6table_nat_net_exit,
 };
 

net/ipv6/netfilter/ip6table_raw.c

···
 	return ret;
 }
 
+static void __net_exit ip6table_raw_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_raw)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_raw,
+					       rawtable_ops);
+}
+
 static void __net_exit ip6table_raw_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_raw)
 		return;
-	ip6t_unregister_table(net, net->ipv6.ip6table_raw, rawtable_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_raw);
 	net->ipv6.ip6table_raw = NULL;
 }
 
 static struct pernet_operations ip6table_raw_net_ops = {
+	.pre_exit = ip6table_raw_net_pre_exit,
 	.exit = ip6table_raw_net_exit,
 };
 

net/ipv6/netfilter/ip6table_security.c

···
 	return ret;
 }
 
+static void __net_exit ip6table_security_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_security)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_security,
+					       sectbl_ops);
+}
+
 static void __net_exit ip6table_security_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_security)
 		return;
-	ip6t_unregister_table(net, net->ipv6.ip6table_security, sectbl_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_security);
 	net->ipv6.ip6table_security = NULL;
 }
 
 static struct pernet_operations ip6table_security_net_ops = {
+	.pre_exit = ip6table_security_net_pre_exit,
 	.exit = ip6table_security_net_exit,
 };