[PATCH 3.16 145/328] netfilter: nf_tables: fix register ordering

[Ben Hutchings]

3.16.62-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Florian Westphal <fw@xxxxxxxxx>

commit d209df3e7f7002d9099fdb0f6df0f972b4386a63 upstream.

We must register nfnetlink ops last, as that exposes nf_tables to
userspace.  Without this, we could theoretically get nfnetlink request
before net->nft state has been initialized.

Fixes: 99633ab29b213 ("netfilter: nf_tables: complete net namespace support")
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
[bwh: Backported to 3.16:
 - We don't call nft_chain_filter_{init,fini}() or
   {,un}register_netdevice_notifier()
 - Adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4042,6 +4042,10 @@ static int __init nf_tables_module_init(
 {
 	int err;
 
+	err = register_pernet_subsys(&nf_tables_net_ops);
+	if (err < 0)
+		return err;
+
 	info = kmalloc(sizeof(struct nft_expr_info) * NFT_RULE_MAXEXPRS,
 		       GFP_KERNEL);
 	if (info == NULL) {
@@ -4053,17 +4057,19 @@ static int __init nf_tables_module_init(
 	if (err < 0)
 		goto err2;
 
+	/* must be last */
 	err = nfnetlink_subsys_register(&nf_tables_subsys);
 	if (err < 0)
 		goto err3;
 
 	pr_info("nf_tables: (c) 2007-2009 Patrick McHardy <kaber@xxxxxxxxx>\n");
-	return register_pernet_subsys(&nf_tables_net_ops);
+	return err;
 err3:
 	nf_tables_core_module_exit();
 err2:
 	kfree(info);
 err1:
+	unregister_pernet_subsys(&nf_tables_net_ops);
 	return err;
 }