From c2f3f31d402be4849b06282c3a5278f2865c9fcc Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Thu, 26 Oct 2017 18:24:37 -0700 Subject: net_sched: use tcf_queue_work() in route 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_route.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'net/sched/cls_route.c') diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c index 9ddde65915d2..4b14ccd8b8f2 100644 --- a/net/sched/cls_route.c +++ b/net/sched/cls_route.c @@ -57,7 +57,10 @@ struct route4_filter { u32 handle; struct route4_bucket *bkt; struct tcf_proto *tp; - struct rcu_head rcu; + union { + struct work_struct work; + struct rcu_head rcu; + }; }; #define ROUTE4_FAILURE ((struct route4_filter *)(-1L)) @@ -254,12 +257,22 @@ static int route4_init(struct tcf_proto *tp) return 0; } -static void route4_delete_filter(struct rcu_head *head) +static void route4_delete_filter_work(struct work_struct *work) { - struct route4_filter *f = container_of(head, struct route4_filter, rcu); + struct route4_filter *f = container_of(work, struct route4_filter, work); + rtnl_lock(); tcf_exts_destroy(&f->exts); kfree(f); + rtnl_unlock(); +} + +static void route4_delete_filter(struct rcu_head *head) +{ + struct route4_filter *f = container_of(head, struct route4_filter, rcu); + + INIT_WORK(&f->work, route4_delete_filter_work); + tcf_queue_work(&f->work); } static void route4_destroy(struct tcf_proto *tp) -- cgit v1.2.3-59-g8ed1b