[4/7] netfilter: iptables: Add a .pre_exit hook in all iptable_foo.c.

diff --git a/net/ipv4/netfilter/iptable_filter.c b/net/ipv4/netfilter/iptable_filter.c
index 9d54b4017e50..8f7bc1ee7453 100644
--- a/net/ipv4/netfilter/iptable_filter.c
+++ b/net/ipv4/netfilter/iptable_filter.c
@@ -72,16 +72,24 @@  static int __net_init iptable_filter_net_init(struct net *net)
 	return 0;
 }
 
+static void __net_exit iptable_filter_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_filter)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_filter,
+					      filter_ops);
+}
+
 static void __net_exit iptable_filter_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_filter)
 		return;
-	ipt_unregister_table(net, net->ipv4.iptable_filter, filter_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_filter);
 	net->ipv4.iptable_filter = NULL;
 }
 
 static struct pernet_operations iptable_filter_net_ops = {
 	.init = iptable_filter_net_init,
+	.pre_exit = iptable_filter_net_pre_exit,
 	.exit = iptable_filter_net_exit,
 };
 
diff --git a/net/ipv4/netfilter/iptable_mangle.c b/net/ipv4/netfilter/iptable_mangle.c
index bb9266ea3785..f703a717ab1d 100644
--- a/net/ipv4/netfilter/iptable_mangle.c
+++ b/net/ipv4/netfilter/iptable_mangle.c
@@ -100,15 +100,23 @@  static int __net_init iptable_mangle_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_mangle_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_mangle)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_mangle,
+					      mangle_ops);
+}
+
 static void __net_exit iptable_mangle_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_mangle)
 		return;
-	ipt_unregister_table(net, net->ipv4.iptable_mangle, mangle_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_mangle);
 	net->ipv4.iptable_mangle = NULL;
 }
 
 static struct pernet_operations iptable_mangle_net_ops = {
+	.pre_exit = iptable_mangle_net_pre_exit,
 	.exit = iptable_mangle_net_exit,
 };
 
diff --git a/net/ipv4/netfilter/iptable_nat.c b/net/ipv4/netfilter/iptable_nat.c
index ad33687b7444..b0143b109f25 100644
--- a/net/ipv4/netfilter/iptable_nat.c
+++ b/net/ipv4/netfilter/iptable_nat.c
@@ -113,16 +113,22 @@  static int __net_init iptable_nat_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_nat_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.nat_table)
+		ipt_nat_unregister_lookups(net);
+}
+
 static void __net_exit iptable_nat_net_exit(struct net *net)
 {
 	if (!net->ipv4.nat_table)
 		return;
-	ipt_nat_unregister_lookups(net);
-	ipt_unregister_table(net, net->ipv4.nat_table, NULL);
+	ipt_unregister_table_exit(net, net->ipv4.nat_table);
 	net->ipv4.nat_table = NULL;
 }
 
 static struct pernet_operations iptable_nat_net_ops = {
+	.pre_exit = iptable_nat_net_pre_exit,
 	.exit	= iptable_nat_net_exit,
 };
 
diff --git a/net/ipv4/netfilter/iptable_raw.c b/net/ipv4/netfilter/iptable_raw.c
index 69697eb4bfc6..9abfe6bf2cb9 100644
--- a/net/ipv4/netfilter/iptable_raw.c
+++ b/net/ipv4/netfilter/iptable_raw.c
@@ -67,15 +67,23 @@  static int __net_init iptable_raw_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_raw_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_raw)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_raw,
+					      rawtable_ops);
+}
+
 static void __net_exit iptable_raw_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_raw)
 		return;
-	ipt_unregister_table(net, net->ipv4.iptable_raw, rawtable_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_raw);
 	net->ipv4.iptable_raw = NULL;
 }
 
 static struct pernet_operations iptable_raw_net_ops = {
+	.pre_exit = iptable_raw_net_pre_exit,
 	.exit = iptable_raw_net_exit,
 };
 
diff --git a/net/ipv4/netfilter/iptable_security.c b/net/ipv4/netfilter/iptable_security.c
index ac633c1db97e..415c1975d770 100644
--- a/net/ipv4/netfilter/iptable_security.c
+++ b/net/ipv4/netfilter/iptable_security.c
@@ -62,16 +62,23 @@  static int __net_init iptable_security_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_security_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_security)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_security,
+					      sectbl_ops);
+}
+
 static void __net_exit iptable_security_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_security)
 		return;
-
-	ipt_unregister_table(net, net->ipv4.iptable_security, sectbl_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_security);
 	net->ipv4.iptable_security = NULL;
 }
 
 static struct pernet_operations iptable_security_net_ops = {
+	.pre_exit = iptable_security_net_pre_exit,
 	.exit = iptable_security_net_exit,
 };