netfilter: nf_conntrack: register pernet subsystem before register L4 proto

In (c296bb4d netfilter: nf_conntrack: refactor l4proto support for netns)
the l4proto gre/dccp/udplite/sctp registration happened before the pernet
subsystem, which is wrong.

Register pernet subsystem before register L4proto since after register
L4proto, init_conntrack may try to access the resources which allocated
in register_pernet_subsys.
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/nf_conntrack_proto_dccp.c

@@ -969,6 +969,10 @@ static int __init nf_conntrack_proto_dccp_init(void)
 {
 	int ret;
 
+	ret = register_pernet_subsys(&dccp_net_ops);
+	if (ret < 0)
+		goto out_pernet;
+
 	ret = nf_ct_l4proto_register(&dccp_proto4);
 	if (ret < 0)
 		goto out_dccp4;
@@ -977,16 +981,12 @@ static int __init nf_conntrack_proto_dccp_init(void)
 	if (ret < 0)
 		goto out_dccp6;
 
-	ret = register_pernet_subsys(&dccp_net_ops);
-	if (ret < 0)
-		goto out_pernet;
-
 	return 0;
-out_pernet:
-	nf_ct_l4proto_unregister(&dccp_proto6);
 out_dccp6:
 	nf_ct_l4proto_unregister(&dccp_proto4);
 out_dccp4:
+	unregister_pernet_subsys(&dccp_net_ops);
+out_pernet:
 	return ret;
 }
 

net/netfilter/nf_conntrack_proto_gre.c

@@ -420,18 +420,18 @@ static int __init nf_ct_proto_gre_init(void)
 {
 	int ret;
 
-	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_gre4);
-	if (ret < 0)
-		goto out_gre4;
-
 	ret = register_pernet_subsys(&proto_gre_net_ops);
 	if (ret < 0)
 		goto out_pernet;
 
+	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_gre4);
+	if (ret < 0)
+		goto out_gre4;
+
 	return 0;
-out_pernet:
-	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_gre4);
 out_gre4:
+	unregister_pernet_subsys(&proto_gre_net_ops);
+out_pernet:
 	return ret;
 }
 

net/netfilter/nf_conntrack_proto_sctp.c

@@ -888,6 +888,10 @@ static int __init nf_conntrack_proto_sctp_init(void)
 {
 	int ret;
 
+	ret = register_pernet_subsys(&sctp_net_ops);
+	if (ret < 0)
+		goto out_pernet;
+
 	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_sctp4);
 	if (ret < 0)
 		goto out_sctp4;
@@ -896,16 +900,12 @@ static int __init nf_conntrack_proto_sctp_init(void)
 	if (ret < 0)
 		goto out_sctp6;
 
-	ret = register_pernet_subsys(&sctp_net_ops);
-	if (ret < 0)
-		goto out_pernet;
-
 	return 0;
-out_pernet:
-	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_sctp6);
 out_sctp6:
 	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_sctp4);
 out_sctp4:
+	unregister_pernet_subsys(&sctp_net_ops);
+out_pernet:
 	return ret;
 }
 

net/netfilter/nf_conntrack_proto_udplite.c

@@ -371,6 +371,10 @@ static int __init nf_conntrack_proto_udplite_init(void)
 {
 	int ret;
 
+	ret = register_pernet_subsys(&udplite_net_ops);
+	if (ret < 0)
+		goto out_pernet;
+
 	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_udplite4);
 	if (ret < 0)
 		goto out_udplite4;
@@ -379,16 +383,12 @@ static int __init nf_conntrack_proto_udplite_init(void)
 	if (ret < 0)
 		goto out_udplite6;
 
-	ret = register_pernet_subsys(&udplite_net_ops);
-	if (ret < 0)
-		goto out_pernet;
-
 	return 0;
-out_pernet:
-	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udplite6);
 out_udplite6:
 	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udplite4);
 out_udplite4:
+	unregister_pernet_subsys(&udplite_net_ops);
+out_pernet:
 	return ret;
 }