netns: do not leak net_generic data on failed init

[pandora-kernel.git] / net / core / net_namespace.c

diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index aefcd7a..31a5ae5 100644 (file)
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -30,6 +30,20 @@ EXPORT_SYMBOL(init_net);
 
 #define INITIAL_NET_GEN_PTRS   13 /* +1 for len +2 for rcu_head */
 
+static unsigned int max_gen_ptrs = INITIAL_NET_GEN_PTRS;
+
+static struct net_generic *net_alloc_generic(void)
+{
+       struct net_generic *ng;
+       size_t generic_size = offsetof(struct net_generic, ptr[max_gen_ptrs]);
+
+       ng = kzalloc(generic_size, GFP_KERNEL);
+       if (ng)
+               ng->len = max_gen_ptrs;
+
+       return ng;
+}
+
 static int net_assign_generic(struct net *net, int id, void *data)
 {
        struct net_generic *ng, *old_ng;
@@ -43,8 +57,7 @@ static int net_assign_generic(struct net *net, int id, void *data)
        if (old_ng->len >= id)
                goto assign;
 
-       ng = kzalloc(sizeof(struct net_generic) +
-                       id * sizeof(void *), GFP_KERNEL);
+       ng = net_alloc_generic();
        if (ng == NULL)
                return -ENOMEM;
 
@@ -59,7 +72,6 @@ static int net_assign_generic(struct net *net, int id, void *data)
         * the old copy for kfree after a grace period.
         */
 
-       ng->len = id;
        memcpy(&ng->ptr, &old_ng->ptr, old_ng->len * sizeof(void*));
 
        rcu_assign_pointer(net->gen, ng);
@@ -71,21 +83,29 @@ assign:
 
 static int ops_init(const struct pernet_operations *ops, struct net *net)
 {
-       int err;
+       int err = -ENOMEM;
+       void *data = NULL;
+
        if (ops->id && ops->size) {
-               void *data = kzalloc(ops->size, GFP_KERNEL);
+               data = kzalloc(ops->size, GFP_KERNEL);
                if (!data)
-                       return -ENOMEM;
+                       goto out;
 
                err = net_assign_generic(net, *ops->id, data);
-               if (err) {
-                       kfree(data);
-                       return err;
-               }
+               if (err)
+                       goto cleanup;
        }
+       err = 0;
        if (ops->init)
-               return ops->init(net);
-       return 0;
+               err = ops->init(net);
+       if (!err)
+               return 0;
+
+cleanup:
+       kfree(data);
+
+out:
+       return err;
 }
 
 static void ops_free(const struct pernet_operations *ops, struct net *net)
@@ -161,18 +181,6 @@ out_undo:
        goto out;
 }
 
-static struct net_generic *net_alloc_generic(void)
-{
-       struct net_generic *ng;
-       size_t generic_size = sizeof(struct net_generic) +
-               INITIAL_NET_GEN_PTRS * sizeof(void *);
-
-       ng = kzalloc(generic_size, GFP_KERNEL);
-       if (ng)
-               ng->len = INITIAL_NET_GEN_PTRS;
-
-       return ng;
-}
 
 #ifdef CONFIG_NET_NS
 static struct kmem_cache *net_cachep;
@@ -448,12 +456,7 @@ static void __unregister_pernet_operations(struct pernet_operations *ops)
 static int __register_pernet_operations(struct list_head *list,
                                        struct pernet_operations *ops)
 {
-       int err = 0;
-       err = ops_init(ops, &init_net);
-       if (err)
-               ops_free(ops, &init_net);
-       return err;
-       
+       return ops_init(ops, &init_net);
 }
 
 static void __unregister_pernet_operations(struct pernet_operations *ops)
@@ -483,6 +486,7 @@ again:
                        }
                        return error;
                }
+               max_gen_ptrs = max_t(unsigned int, max_gen_ptrs, *ops->id);
        }
        error = __register_pernet_operations(list, ops);
        if (error) {