netfilter: nf_tables: complete net namespace support

Register family per netnamespace to ensure that sets are
only visible in its approapriate namespace.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index bcc4a8e..da68c9a 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -22,6 +22,7 @@
 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
 #include <net/netns/conntrack.h>
 #endif
+#include <net/netns/nftables.h>
 #include <net/netns/xfrm.h>
 
 struct user_namespace;
@@ -101,6 +102,9 @@
 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
 	struct netns_ct		ct;
 #endif
+#if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
+	struct netns_nftables	nft;
+#endif
 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
 	struct netns_nf_frag	nf_frag;
 #endif