net/sched: act_api: avoid non-contiguous action array

In tcf_action_add, when putting the reference for the bound actions
it assigns NULLs to just created actions passing a non contiguous
array to tcf_action_put_many.
Refactor the code so the actions array is always contiguous.
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net/sched/act_api.c

@@ -1135,18 +1135,29 @@ static int tcf_action_put(struct tc_action *p)
 	return __tcf_action_put(p, false);
 }
 
-/* Put all actions in this array, skip those NULL's. */
 static void tcf_action_put_many(struct tc_action *actions[])
 {
+	struct tc_action *a;
 	int i;
 
-	for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
-		struct tc_action *a = actions[i];
-		const struct tc_action_ops *ops;
+	tcf_act_for_each_action(i, a, actions) {
+		const struct tc_action_ops *ops = a->ops;
+		if (tcf_action_put(a))
+			module_put(ops->owner);
+	}
+}
 
-		if (!a)
+static void tca_put_bound_many(struct tc_action *actions[], int init_res[])
+{
+	struct tc_action *a;
+	int i;
+
+	tcf_act_for_each_action(i, a, actions) {
+		const struct tc_action_ops *ops = a->ops;
+
+		if (init_res[i] == ACT_P_CREATED)
 			continue;
-		ops = a->ops;
+
 		if (tcf_action_put(a))
 			module_put(ops->owner);
 	}
@@ -1975,7 +1986,7 @@ static int tcf_action_add(struct net *net, struct nlattr *nla,
 			  struct netlink_ext_ack *extack)
 {
 	size_t attr_size = 0;
-	int loop, ret, i;
+	int loop, ret;
 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
 	int init_res[TCA_ACT_MAX_PRIO] = {};
 
@@ -1988,13 +1999,11 @@ static int tcf_action_add(struct net *net, struct nlattr *nla,
 
 	if (ret < 0)
 		return ret;
+
 	ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
 
-	/* only put existing actions */
-	for (i = 0; i < TCA_ACT_MAX_PRIO; i++)
-		if (init_res[i] == ACT_P_CREATED)
-			actions[i] = NULL;
-	tcf_action_put_many(actions);
+	/* only put bound actions */
+	tca_put_bound_many(actions, init_res);
 
 	return ret;
 }