[PATCH 4.9 062/105] net_sched: always reset qdisc backlog in qdisc_reset()

[Greg Kroah-Hartman]

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

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

From: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>


[ Upstream commit c8e1812960eeae42e2183154927028511c4bc566 ]

SKB stored in qdisc->gso_skb also counted into backlog.

Some qdiscs don't reset backlog to zero in ->reset(),
for example sfq just dequeue and free all queued skb.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Fixes: 2ccccf5fb43f ("net_sched: update hierarchical backlog too")
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/sched/sch_generic.c |    1 +
 1 file changed, 1 insertion(+)

--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -681,6 +681,7 @@ void qdisc_reset(struct Qdisc *qdisc)
 		qdisc->gso_skb = NULL;
 	}
 	qdisc->q.qlen = 0;
+	qdisc->qstats.backlog = 0;
 }
 EXPORT_SYMBOL(qdisc_reset);