From f93e1cdcf42c1218e2a73be477d8ac21135e7f56 Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Sat, 20 May 2017 15:01:32 +0200 Subject: [PATCH] net/sched: fix filter flushing When user instructs to remove all filters from chain, we cannot destroy the chain as other actions may hold a reference. Also the put in errout would try to destroy it again. So instead, just walk the chain and remove all existing filters. Fixes: 5bc1701881e3 ("net: sched: introduce multichain support for filters") Signed-off-by: Jiri Pirko Acked-by: Cong Wang Signed-off-by: David S. Miller --- net/sched/cls_api.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c index 85088ed07f6a..01a8b8b4bab8 100644 --- a/net/sched/cls_api.c +++ b/net/sched/cls_api.c @@ -201,15 +201,22 @@ static struct tcf_chain *tcf_chain_create(struct tcf_block *block, return chain; } -static void tcf_chain_destroy(struct tcf_chain *chain) +static void tcf_chain_flush(struct tcf_chain *chain) { struct tcf_proto *tp; - list_del(&chain->list); + if (*chain->p_filter_chain) + RCU_INIT_POINTER(*chain->p_filter_chain, NULL); while ((tp = rtnl_dereference(chain->filter_chain)) != NULL) { RCU_INIT_POINTER(chain->filter_chain, tp->next); tcf_proto_destroy(tp); } +} + +static void tcf_chain_destroy(struct tcf_chain *chain) +{ + list_del(&chain->list); + tcf_chain_flush(chain); kfree(chain); } @@ -510,7 +517,7 @@ replay: if (n->nlmsg_type == RTM_DELTFILTER && prio == 0) { tfilter_notify_chain(net, skb, n, chain, RTM_DELTFILTER); - tcf_chain_destroy(chain); + tcf_chain_flush(chain); err = 0; goto errout; } -- 2.20.1