Commit aecc5cef authored Sep 19, 2016 by Jamal Hadi Salim Committed by David S. Miller Sep 20, 2016

net sched actions: fix GETing actions



With the batch changes that translated transient actions into
a temporary list lost in the translation was the fact that
tcf_action_destroy() will eventually delete the action from
the permanent location if the refcount is zero.

Example of what broke:
...add a gact action to drop
sudo $TC actions add action drop index 10
...now retrieve it, looks good
sudo $TC actions get action gact index 10
...retrieve it again and find it is gone!
sudo $TC actions get action gact index 10

Fixes: 22dc13c8 ("net_sched: convert tcf_exts from list to pointer array"),
Fixes: 824a7e88 ("net_sched: remove an unnecessary list_del()")
Fixes: f07fed82 ("net_sched: remove the leftover cleanup_a()")

Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 1d9423ae

net/sched/act_api.c

+20 −0

Original line number	Diff line number	Diff line
		@@ -592,6 +592,17 @@ err_out:
		return ERR_PTR(err);
		}

		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)
		{
		@@ -611,8 +622,15 @@ int tcf_action_init(struct net net, struct nlattr nla, struct nlattr *est,
		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:
		@@ -882,6 +900,8 @@ 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);
		}

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