[NETFILTER]: x_tables: return new table from {arp,ip,ip6}t_register_table()

Typical table module registers xt_table structure (i.e. packet_filter)
and link it to list during it. We can't use one template for it because
corresponding list_head will become corrupted. We also can't unregister
with template because it wasn't changed at all and thus doesn't know in
which list it is.

So, we duplicate template at the very first step of table registration.
Table modules will save it for use during unregistration time and actual
filtering.

Do it at once to not screw bisection.

P.S.: renaming i.e. packet_filter => __packet_filter is temporary until
      full netnsization of table modules is done.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 17 insertions, 11 deletions

diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index bc22ea421a9..99dd62d93f4 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -2048,7 +2048,8 @@ do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
 	return ret;
 }
 
-int ipt_register_table(struct xt_table *table, const struct ipt_replace *repl)
+struct xt_table *ipt_register_table(struct net *net, struct xt_table *table,
+				    const struct ipt_replace *repl)
 {
 	int ret;
 	struct xt_table_info *newinfo;
@@ -2058,8 +2059,10 @@ int ipt_register_table(struct xt_table *table, const struct ipt_replace *repl)
 	struct xt_table *new_table;
 
 	newinfo = xt_alloc_table_info(repl->size);
-	if (!newinfo)
-		return -ENOMEM;
+	if (!newinfo) {
+		ret = -ENOMEM;
+		goto out;
+	}
 
 	/* choose the copy on our node/cpu, but dont care about preemption */
 	loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
@@ -2070,18 +2073,21 @@ int ipt_register_table(struct xt_table *table, const struct ipt_replace *repl)
 			      repl->num_entries,
 			      repl->hook_entry,
 			      repl->underflow);
-	if (ret != 0) {
-		xt_free_table_info(newinfo);
-		return ret;
-	}
+	if (ret != 0)
+		goto out_free;
 
-	new_table = xt_register_table(&init_net, table, &bootstrap, newinfo);
+	new_table = xt_register_table(net, table, &bootstrap, newinfo);
 	if (IS_ERR(new_table)) {
-		xt_free_table_info(newinfo);
-		return PTR_ERR(new_table);
+		ret = PTR_ERR(new_table);
+		goto out_free;
 	}
 
-	return 0;
+	return new_table;
+
+out_free:
+	xt_free_table_info(newinfo);
+out:
+	return ERR_PTR(ret);
 }
 
 void ipt_unregister_table(struct xt_table *table)