[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>
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index d62f722..d7fbb1b 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -667,9 +667,16 @@
struct xt_table_info *private;
struct xt_table *t;
+ /* Don't add one object to multiple lists. */
+ table = kmemdup(table, sizeof(struct xt_table), GFP_KERNEL);
+ if (!table) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
ret = mutex_lock_interruptible(&xt[table->af].mutex);
if (ret != 0)
- goto out;
+ goto out_free;
/* Don't autoload: we'd eat our tail... */
list_for_each_entry(t, &net->xt.tables[table->af], list) {
@@ -697,6 +704,8 @@
unlock:
mutex_unlock(&xt[table->af].mutex);
+out_free:
+ kfree(table);
out:
return ERR_PTR(ret);
}
@@ -710,6 +719,7 @@
private = table->private;
list_del(&table->list);
mutex_unlock(&xt[table->af].mutex);
+ kfree(table);
return private;
}
