From e910af676b565ecc16bcd6c896ecb68157396ecc Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Thu, 26 Oct 2017 18:24:30 -0700 Subject: [PATCH] net_sched: use tcf_queue_work() in bpf 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_bpf.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/net/sched/cls_bpf.c b/net/sched/cls_bpf.c index 520c5027646a..037a3ae86829 100644 --- a/net/sched/cls_bpf.c +++ b/net/sched/cls_bpf.c @@ -49,7 +49,10 @@ struct cls_bpf_prog { struct sock_filter *bpf_ops; const char *bpf_name; struct tcf_proto *tp; - struct rcu_head rcu; + union { + struct work_struct work; + struct rcu_head rcu; + }; }; static const struct nla_policy bpf_policy[TCA_BPF_MAX + 1] = { @@ -257,9 +260,21 @@ static void __cls_bpf_delete_prog(struct cls_bpf_prog *prog) kfree(prog); } +static void cls_bpf_delete_prog_work(struct work_struct *work) +{ + struct cls_bpf_prog *prog = container_of(work, struct cls_bpf_prog, work); + + rtnl_lock(); + __cls_bpf_delete_prog(prog); + rtnl_unlock(); +} + static void cls_bpf_delete_prog_rcu(struct rcu_head *rcu) { - __cls_bpf_delete_prog(container_of(rcu, struct cls_bpf_prog, rcu)); + struct cls_bpf_prog *prog = container_of(rcu, struct cls_bpf_prog, rcu); + + INIT_WORK(&prog->work, cls_bpf_delete_prog_work); + tcf_queue_work(&prog->work); } static void __cls_bpf_delete(struct tcf_proto *tp, struct cls_bpf_prog *prog) -- 2.20.1