net_sched actions: use nla_parse_nested()

[cascardo/linux.git] / net / sched / act_api.c

diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index d09d068..f893d18 100644 (file)
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -341,22 +341,25 @@ int tcf_register_action(struct tc_action_ops *act,
        if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup)
                return -EINVAL;
 
+       /* We have to register pernet ops before making the action ops visible,
+        * otherwise tcf_action_init_1() could get a partially initialized
+        * netns.
+        */
+       ret = register_pernet_subsys(ops);
+       if (ret)
+               return ret;
+
        write_lock(&act_mod_lock);
        list_for_each_entry(a, &act_base, head) {
                if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
                        write_unlock(&act_mod_lock);
+                       unregister_pernet_subsys(ops);
                        return -EEXIST;
                }
        }
        list_add_tail(&act->head, &act_base);
        write_unlock(&act_mod_lock);
 
-       ret = register_pernet_subsys(ops);
-       if (ret) {
-               tcf_unregister_action(act, ops);
-               return ret;
-       }
-
        return 0;
 }
 EXPORT_SYMBOL(tcf_register_action);
@@ -367,8 +370,6 @@ int tcf_unregister_action(struct tc_action_ops *act,
        struct tc_action_ops *a;
        int err = -ENOENT;
 
-       unregister_pernet_subsys(ops);
-
        write_lock(&act_mod_lock);
        list_for_each_entry(a, &act_base, head) {
                if (a == act) {
@@ -378,6 +379,8 @@ int tcf_unregister_action(struct tc_action_ops *act,
                }
        }
        write_unlock(&act_mod_lock);
+       if (!err)
+               unregister_pernet_subsys(ops);
        return err;
 }
 EXPORT_SYMBOL(tcf_unregister_action);
@@ -592,9 +595,19 @@ err_out:
        return ERR_PTR(err);
 }
 
-int tcf_action_init(struct net *net, struct nlattr *nla,
-                                 struct nlattr *est, char *name, int ovr,
-                                 int bind, struct list_head *actions)
+static void cleanup_a(struct list_head *actions, int ovr)
+{
+       struct tc_action *a;
+
+       if (!ovr)
+               return;
+
+       list_for_each_entry(a, actions, list)
+               a->tcfa_refcnt--;
+}
+
+int tcf_action_init(struct net *net, struct nlattr *nla, struct nlattr *est,
+                   char *name, int ovr, int bind, struct list_head *actions)
 {
        struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
        struct tc_action *act;
@@ -612,8 +625,15 @@ int tcf_action_init(struct net *net, struct nlattr *nla,
                        goto err;
                }
                act->order = i;
+               if (ovr)
+                       act->tcfa_refcnt++;
                list_add_tail(&act->list, actions);
        }
+
+       /* Remove the temp refcnt which was necessary to protect against
+        * destroying an existing action which was being replaced
+        */
+       cleanup_a(actions, ovr);
        return 0;
 
 err:
@@ -883,6 +903,8 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
                        goto err;
                }
                act->order = i;
+               if (event == RTM_GETACTION)
+                       act->tcfa_refcnt++;
                list_add_tail(&act->list, &actions);
        }
 
@@ -923,9 +945,8 @@ tcf_add_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
        return err;
 }
 
-static int
-tcf_action_add(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
-              u32 portid, int ovr)
+static int tcf_action_add(struct net *net, struct nlattr *nla,
+                         struct nlmsghdr *n, u32 portid, int ovr)
 {
        int ret = 0;
        LIST_HEAD(actions);
@@ -988,8 +1009,7 @@ replay:
        return ret;
 }
 
-static struct nlattr *
-find_dump_kind(const struct nlmsghdr *n)
+static struct nlattr *find_dump_kind(const struct nlmsghdr *n)
 {
        struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
        struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
@@ -1008,16 +1028,14 @@ find_dump_kind(const struct nlmsghdr *n)
 
        if (tb[1] == NULL)
                return NULL;
-       if (nla_parse(tb2, TCA_ACT_MAX, nla_data(tb[1]),
-                     nla_len(tb[1]), NULL) < 0)
+       if (nla_parse_nested(tb2, TCA_ACT_MAX, tb[1], NULL) < 0)
                return NULL;
        kind = tb2[TCA_ACT_KIND];
 
        return kind;
 }
 
-static int
-tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
+static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
 {
        struct net *net = sock_net(skb->sk);
        struct nlmsghdr *nlh;