From 94cdb47566b799649e996e1fb9de2a503dada763 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Thu, 26 Oct 2017 18:24:32 -0700 Subject: net_sched: use tcf_queue_work() in flow filter Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: Chris Mi Cc: Daniel Borkmann Cc: Jiri Pirko Cc: John Fastabend Cc: Jamal Hadi Salim Cc: "Paul E. McKenney" Signed-off-by: Cong Wang Signed-off-by: David S. Miller --- net/sched/cls_flow.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'net/sched/cls_flow.c') diff --git a/net/sched/cls_flow.c b/net/sched/cls_flow.c index 2a3a60ec5b86..67f3a2af6aab 100644 --- a/net/sched/cls_flow.c +++ b/net/sched/cls_flow.c @@ -57,7 +57,10 @@ struct flow_filter { u32 divisor; u32 baseclass; u32 hashrnd; - struct rcu_head rcu; + union { + struct work_struct work; + struct rcu_head rcu; + }; }; static inline u32 addr_fold(void *addr) @@ -369,14 +372,24 @@ static const struct nla_policy flow_policy[TCA_FLOW_MAX + 1] = { [TCA_FLOW_PERTURB] = { .type = NLA_U32 }, }; -static void flow_destroy_filter(struct rcu_head *head) +static void flow_destroy_filter_work(struct work_struct *work) { - struct flow_filter *f = container_of(head, struct flow_filter, rcu); + 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); kfree(f); + rtnl_unlock(); +} + +static void flow_destroy_filter(struct rcu_head *head) +{ + struct flow_filter *f = container_of(head, struct flow_filter, rcu); + + INIT_WORK(&f->work, flow_destroy_filter_work); + tcf_queue_work(&f->work); } static int flow_change(struct net *net, struct sk_buff *in_skb, -- cgit