From 35c55fc156d85a396a975fc17636f560fc02fd65 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Mon, 6 Nov 2017 13:47:30 -0800 Subject: cls_u32: 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_u32.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'net/sched') diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c index dadd1b344497..b58eccb21f03 100644 --- a/net/sched/cls_u32.c +++ b/net/sched/cls_u32.c @@ -399,6 +399,7 @@ static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n, bool free_pf) { tcf_exts_destroy(&n->exts); + tcf_exts_put_net(&n->exts); if (n->ht_down) n->ht_down->refcnt--; #ifdef CONFIG_CLS_U32_PERF @@ -476,6 +477,7 @@ static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key) RCU_INIT_POINTER(*kp, key->next); tcf_unbind_filter(tp, &key->res); + tcf_exts_get_net(&key->exts); call_rcu(&key->rcu, u32_delete_key_freepf_rcu); return 0; } @@ -588,7 +590,10 @@ static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht) rtnl_dereference(n->next)); tcf_unbind_filter(tp, &n->res); u32_remove_hw_knode(tp, n->handle); - call_rcu(&n->rcu, u32_delete_key_freepf_rcu); + if (tcf_exts_get_net(&n->exts)) + call_rcu(&n->rcu, u32_delete_key_freepf_rcu); + else + u32_destroy_key(n->tp, n, true); } } } @@ -949,6 +954,7 @@ static int u32_change(struct net *net, struct sk_buff *in_skb, u32_replace_knode(tp, tp_c, new); tcf_unbind_filter(tp, &n->res); + tcf_exts_get_net(&n->exts); call_rcu(&n->rcu, u32_delete_key_rcu); return 0; } -- cgit v1.2.3