1 files changed, 37 insertions, 18 deletions

diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index d09d0687594b..a512b18c0088 100644
--- 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];
@@ -1016,8 +1036,7 @@ find_dump_kind(const struct nlmsghdr *n)
 	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;