From 3fd51de5e3ba447624a08a8ba29f90d94f0fe909 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Mon, 6 Nov 2017 13:47:27 -0800 Subject: cls_route: 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_route.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c index 4b14ccd8b8f2..ac9a5b8825b9 100644 --- a/net/sched/cls_route.c +++ b/net/sched/cls_route.c @@ -257,13 +257,19 @@ static int route4_init(struct tcf_proto *tp) return 0; } +static void __route4_delete_filter(struct route4_filter *f) +{ + tcf_exts_destroy(&f->exts); + tcf_exts_put_net(&f->exts); + kfree(f); +} + static void route4_delete_filter_work(struct work_struct *work) { struct route4_filter *f = container_of(work, struct route4_filter, work); rtnl_lock(); - tcf_exts_destroy(&f->exts); - kfree(f); + __route4_delete_filter(f); rtnl_unlock(); } @@ -297,7 +303,10 @@ static void route4_destroy(struct tcf_proto *tp) next = rtnl_dereference(f->next); RCU_INIT_POINTER(b->ht[h2], next); tcf_unbind_filter(tp, &f->res); - call_rcu(&f->rcu, route4_delete_filter); + if (tcf_exts_get_net(&f->exts)) + call_rcu(&f->rcu, route4_delete_filter); + else + __route4_delete_filter(f); } } RCU_INIT_POINTER(head->table[h1], NULL); @@ -338,6 +347,7 @@ static int route4_delete(struct tcf_proto *tp, void *arg, bool *last) /* Delete it */ tcf_unbind_filter(tp, &f->res); + tcf_exts_get_net(&f->exts); call_rcu(&f->rcu, route4_delete_filter); /* Strip RTNL protected tree */ @@ -541,6 +551,7 @@ static int route4_change(struct net *net, struct sk_buff *in_skb, *arg = f; if (fold) { tcf_unbind_filter(tp, &fold->res); + tcf_exts_get_net(&fold->exts); call_rcu(&fold->rcu, route4_delete_filter); } return 0; -- cgit v1.2.3-59-g8ed1b