Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 22f7cec9 authored by Cong Wang's avatar Cong Wang Committed by David S. Miller
Browse files

cls_flow: use tcf_exts_get_net() before call_rcu() 



Hold netns refcnt before call_rcu() and release it after
the tcf_exts_destroy() is done.

Note, on ->destroy() path we have to respect the return value
of tcf_exts_get_net(), on other paths it should always return
true, so we don't need to care.

Cc: Lucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ed148168

net/sched/cls_flow.c

+18 −6
Original line number Diff line number Diff line
@@ -372,15 +372,21 @@ static const struct nla_policy flow_policy[TCA_FLOW_MAX + 1] = { 
	[TCA_FLOW_PERTURB]	= { .type = NLA_U32 },

};



static void flow_destroy_filter_work(struct work_struct *work)

static void __flow_destroy_filter(struct flow_filter *f)

{

	struct flow_filter *f = container_of(work, struct flow_filter, work);



	rtnl_lock();

	del_timer_sync(&f->perturb_timer);

	tcf_exts_destroy(&f->exts);

	tcf_em_tree_destroy(&f->ematches);

	tcf_exts_put_net(&f->exts);

	kfree(f);

}



static void flow_destroy_filter_work(struct work_struct *work)

{

	struct flow_filter *f = container_of(work, struct flow_filter, work);



	rtnl_lock();

	__flow_destroy_filter(f);

	rtnl_unlock();

}
@@ -552,8 +558,10 @@ static int flow_change(struct net *net, struct sk_buff *in_skb, 


	*arg = fnew;



	if (fold)

	if (fold) {

		tcf_exts_get_net(&fold->exts);

		call_rcu(&fold->rcu, flow_destroy_filter);

	}

	return 0;



err2:
@@ -570,6 +578,7 @@ static int flow_delete(struct tcf_proto *tp, void *arg, bool *last) 
	struct flow_filter *f = arg;



	list_del_rcu(&f->list);

	tcf_exts_get_net(&f->exts);

	call_rcu(&f->rcu, flow_destroy_filter);

	*last = list_empty(&head->filters);

	return 0;
@@ -594,7 +603,10 @@ static void flow_destroy(struct tcf_proto *tp) 


	list_for_each_entry_safe(f, next, &head->filters, list) {

		list_del_rcu(&f->list);

		if (tcf_exts_get_net(&f->exts))

			call_rcu(&f->rcu, flow_destroy_filter);

		else

			__flow_destroy_filter(f);

	}

	kfree_rcu(head, rcu);

}