From 0dadc117ac8bc78d8144e862ac8ad23f342f9ea8 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Mon, 6 Nov 2017 13:47:24 -0800 Subject: [PATCH] cls_flower: 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 Cc: Jamal Hadi Salim Cc: Jiri Pirko Signed-off-by: Cong Wang Signed-off-by: David S. Miller --- net/sched/cls_flower.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index 5b5722c8b32c..7a838d1c1c00 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -218,13 +218,19 @@ static int fl_init(struct tcf_proto *tp) return 0; } +static void __fl_destroy_filter(struct cls_fl_filter *f) +{ + tcf_exts_destroy(&f->exts); + tcf_exts_put_net(&f->exts); + kfree(f); +} + static void fl_destroy_filter_work(struct work_struct *work) { struct cls_fl_filter *f = container_of(work, struct cls_fl_filter, work); rtnl_lock(); - tcf_exts_destroy(&f->exts); - kfree(f); + __fl_destroy_filter(f); rtnl_unlock(); } @@ -318,7 +324,10 @@ static void __fl_delete(struct tcf_proto *tp, struct cls_fl_filter *f) if (!tc_skip_hw(f->flags)) fl_hw_destroy_filter(tp, f); tcf_unbind_filter(tp, &f->res); - call_rcu(&f->rcu, fl_destroy_filter); + if (tcf_exts_get_net(&f->exts)) + call_rcu(&f->rcu, fl_destroy_filter); + else + __fl_destroy_filter(f); } static void fl_destroy_sleepable(struct work_struct *work) @@ -988,6 +997,7 @@ static int fl_change(struct net *net, struct sk_buff *in_skb, idr_replace_ext(&head->handle_idr, fnew, fnew->handle); list_replace_rcu(&fold->list, &fnew->list); tcf_unbind_filter(tp, &fold->res); + tcf_exts_get_net(&fold->exts); call_rcu(&fold->rcu, fl_destroy_filter); } else { list_add_tail_rcu(&fnew->list, &head->filters); -- 2.39.5