From 0552c8afa077889b4704ef5ee88b03063ad45023 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Thu, 26 Oct 2017 18:24:33 -0700 Subject: [PATCH] net_sched: use tcf_queue_work() in flower 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_flower.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index b480d7c792ba..5b5722c8b32c 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -87,7 +87,10 @@ struct cls_fl_filter { struct list_head list; u32 handle; u32 flags; - struct rcu_head rcu; + union { + struct work_struct work; + struct rcu_head rcu; + }; struct net_device *hw_dev; }; @@ -215,12 +218,22 @@ static int fl_init(struct tcf_proto *tp) return 0; } -static void fl_destroy_filter(struct rcu_head *head) +static void fl_destroy_filter_work(struct work_struct *work) { - struct cls_fl_filter *f = container_of(head, struct cls_fl_filter, rcu); + struct cls_fl_filter *f = container_of(work, struct cls_fl_filter, work); + rtnl_lock(); tcf_exts_destroy(&f->exts); kfree(f); + rtnl_unlock(); +} + +static void fl_destroy_filter(struct rcu_head *head) +{ + struct cls_fl_filter *f = container_of(head, struct cls_fl_filter, rcu); + + INIT_WORK(&f->work, fl_destroy_filter_work); + tcf_queue_work(&f->work); } static void fl_hw_destroy_filter(struct tcf_proto *tp, struct cls_fl_filter *f) -- 2.20.1