[NETFILTER]: nf_conntrack: remove ugly hack in l4proto registration

Remove ugly special-casing of nf_conntrack_l4proto_generic, all it
wants is its sysctl tables registered, so do that explicitly in an
init function and move the remaining protocol initialization and
cleanup code to nf_conntrack_proto.c as well.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/netfilter/nf_conntrack_core.h

@@ -27,6 +27,9 @@ extern unsigned int nf_conntrack_in(int pf,
 extern int nf_conntrack_init(void);
 extern void nf_conntrack_cleanup(void);
 
+extern int nf_conntrack_proto_init(void);
+extern void nf_conntrack_proto_fini(void);
+
 struct nf_conntrack_l3proto;
 extern struct nf_conntrack_l3proto *nf_ct_find_l3proto(u_int16_t pf);
 /* Like above, but you already have conntrack read lock. */

net/netfilter/nf_conntrack_core.c

@@ -1152,14 +1152,7 @@ void nf_conntrack_cleanup(void)
 	free_conntrack_hash(nf_conntrack_hash, nf_conntrack_vmalloc,
 			    nf_conntrack_htable_size);
 
-	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_generic);
-
-	/* free l3proto protocol tables */
-	for (i = 0; i < PF_MAX; i++)
-		if (nf_ct_protos[i]) {
-			kfree(nf_ct_protos[i]);
-			nf_ct_protos[i] = NULL;
-		}
+	nf_conntrack_proto_fini();
 }
 
 static struct list_head *alloc_hashtable(int size, int *vmalloced)
@@ -1237,7 +1230,6 @@ module_param_call(hashsize, set_hashsize, param_get_uint,
 
 int __init nf_conntrack_init(void)
 {
-	unsigned int i;
 	int ret;
 
 	/* Idea from tcp.c: use 1/16384 of memory.  On i386: 32MB
@@ -1279,16 +1271,10 @@ int __init nf_conntrack_init(void)
 		goto err_free_conntrack_slab;
 	}
 
-	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_generic);
+	ret = nf_conntrack_proto_init();
 	if (ret < 0)
 		goto out_free_expect_slab;
 
-	/* Don't NEED lock here, but good form anyway. */
-	write_lock_bh(&nf_conntrack_lock);
-	for (i = 0; i < AF_MAX; i++)
-		nf_ct_l3protos[i] = &nf_conntrack_l3proto_generic;
-	write_unlock_bh(&nf_conntrack_lock);
-
 	/* For use by REJECT target */
 	rcu_assign_pointer(ip_ct_attach, __nf_conntrack_attach);
 

net/netfilter/nf_conntrack_proto.c

@@ -294,9 +294,6 @@ int nf_conntrack_l4proto_register(struct nf_conntrack_l4proto *l4proto)
 		goto out;
 	}
 
-	if (l4proto == &nf_conntrack_l4proto_generic)
-		return nf_ct_l4proto_register_sysctl(l4proto);
-
 	mutex_lock(&nf_ct_proto_mutex);
 retry:
 	if (nf_ct_protos[l4proto->l3proto]) {
@@ -353,11 +350,6 @@ void nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
 {
 	BUG_ON(l4proto->l3proto >= PF_MAX);
 
-	if (l4proto == &nf_conntrack_l4proto_generic) {
-		nf_ct_l4proto_unregister_sysctl(l4proto);
-		return;
-	}
-
 	mutex_lock(&nf_ct_proto_mutex);
 	BUG_ON(nf_ct_protos[l4proto->l3proto][l4proto->l4proto] != l4proto);
 	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
@@ -371,3 +363,29 @@ void nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
 	nf_ct_iterate_cleanup(kill_l4proto, l4proto);
 }
 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_unregister);
+
+int nf_conntrack_proto_init(void)
+{
+	unsigned int i;
+	int err;
+
+	err = nf_ct_l4proto_register_sysctl(&nf_conntrack_l4proto_generic);
+	if (err < 0)
+		return err;
+
+	for (i = 0; i < AF_MAX; i++)
+		rcu_assign_pointer(nf_ct_l3protos[i],
+				   &nf_conntrack_l3proto_generic);
+	return 0;
+}
+
+void nf_conntrack_proto_fini(void)
+{
+	unsigned int i;
+
+	nf_ct_l4proto_unregister_sysctl(&nf_conntrack_l4proto_generic);
+
+	/* free l3proto protocol tables */
+	for (i = 0; i < PF_MAX; i++)
+		kfree(nf_ct_protos[i]);
+}