[PATCH 4.9 17/25] cls_matchall: fix tcf_unbind_filter missing

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Hangbin Liu <liuhangbin@xxxxxxxxx>

[ Upstream commit a51c76b4dfb30496dc65396a957ef0f06af7fb22 ]

Fix tcf_unbind_filter missing in cls_matchall as this will trigger
WARN_ON() in cbq_destroy_class().

Fixes: fd62d9f5c575f ("net/sched: matchall: Fix configuration race")
Reported-by: Li Shuang <shuali@xxxxxxxxxx>
Signed-off-by: Hangbin Liu <liuhangbin@xxxxxxxxx>
Acked-by: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/sched/cls_matchall.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/net/sched/cls_matchall.c
+++ b/net/sched/cls_matchall.c
@@ -94,6 +94,8 @@ static bool mall_destroy(struct tcf_prot
 	if (!head)
 		return true;
 
+	tcf_unbind_filter(tp, &head->res);
+
 	if (tc_should_offload(dev, tp, head->flags))
 		mall_destroy_hw_filter(tp, head, (unsigned long) head);