From aecc5cefc389735b5327d234e11d1fe505e1c280 Mon Sep 17 00:00:00 2001
From: Jamal Hadi Salim <jhs@mojatatu.com>
Date: Mon, 19 Sep 2016 19:02:51 -0400
Subject: [PATCH] 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: 22dc13c837c3 ("net_sched: convert tcf_exts from list to pointer array"),
Fixes: 824a7e8863b3 ("net_sched: remove an unnecessary list_del()")
Fixes: f07fed82ad79 ("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>
---
net/sched/act_api.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index d0aceb1740b12..c9102172ce3b0 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -592,6 +592,17 @@ struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla,
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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