Revert "ipv6: Prevent access to uninitialized fib_table_hash via /proc/net/ipv6_route"

This reverts commit 2a0c451a.

It causes crashes, because now ip6_null_entry is used before
it is initialized.
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/ip6_fib.h

@@ -271,8 +271,6 @@ extern void			fib6_run_gc(unsigned long expires,
 extern void			fib6_gc_cleanup(void);
 
 extern int			fib6_init(void);
-extern int			fib6_init_late(void);
-extern void			fib6_cleanup_late(void);
 
 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 extern int			fib6_rules_init(void);

net/ipv6/ip6_fib.c

@@ -1692,25 +1692,21 @@ int __init fib6_init(void)
 	ret = register_pernet_subsys(&fib6_net_ops);
 	if (ret)
 		goto out_kmem_cache_create;
+
+	ret = __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib,
+			      NULL);
+	if (ret)
+		goto out_unregister_subsys;
 out:
 	return ret;
 
+out_unregister_subsys:
+	unregister_pernet_subsys(&fib6_net_ops);
 out_kmem_cache_create:
 	kmem_cache_destroy(fib6_node_kmem);
 	goto out;
 }
 
-int __init fib6_init_late(void)
-{
-	return __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib,
-			       NULL);
-}
-
-void fib6_cleanup_late(void)
-{
-	rtnl_unregister(PF_INET6, RTM_GETROUTE);
-}
-
 void fib6_gc_cleanup(void)
 {
 	unregister_pernet_subsys(&fib6_net_ops);

net/ipv6/route.c

@@ -3018,13 +3018,9 @@ int __init ip6_route_init(void)
 	if (ret)
 		goto out_kmem_cache;
 
-	ret = fib6_init();
-	if (ret)
-		goto out_dst_entries;
-
 	ret = register_pernet_subsys(&ip6_route_net_ops);
 	if (ret)
-		goto out_fib6_init;
+		goto out_dst_entries;
 
 	ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
 
@@ -3039,13 +3035,13 @@ int __init ip6_route_init(void)
 	init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
 	init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
   #endif
-	ret = fib6_init_late();
+	ret = fib6_init();
 	if (ret)
 		goto out_register_subsys;
 
 	ret = xfrm6_init();
 	if (ret)
-		goto out_fib6_init_late;
+		goto out_fib6_init;
 
 	ret = fib6_rules_init();
 	if (ret)
@@ -3068,12 +3064,10 @@ int __init ip6_route_init(void)
 	fib6_rules_cleanup();
 xfrm6_init:
 	xfrm6_fini();
-out_fib6_init_late:
-	fib6_cleanup_late();
-out_register_subsys:
-	unregister_pernet_subsys(&ip6_route_net_ops);
 out_fib6_init:
 	fib6_gc_cleanup();
+out_register_subsys:
+	unregister_pernet_subsys(&ip6_route_net_ops);
 out_dst_entries:
 	dst_entries_destroy(&ip6_dst_blackhole_ops);
 out_kmem_cache: