fq_codel: fix a use-after-free

[ Upstream commit 052cbda41fdc243a8d40cce7ab3a6327b4b2887e ]

Fixes: 25331d6ce42b ("net: sched: implement qstat helper routines")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/sched/sch_fq_codel.c b/net/sched/sch_fq_codel.c
index c244c45b78d7feca32fda3b925f7605aebf0a5b6..9291598b5aad42d96dd23179dc1ceb624a0bceaa 100644 (file)
--- a/net/sched/sch_fq_codel.c
+++ b/net/sched/sch_fq_codel.c
@@ -162,10 +162,10 @@ static unsigned int fq_codel_drop(struct Qdisc *sch)
        skb = dequeue_head(flow);
        len = qdisc_pkt_len(skb);
        q->backlogs[idx] -= len;
-       kfree_skb(skb);
        sch->q.qlen--;
        qdisc_qstats_drop(sch);
        qdisc_qstats_backlog_dec(sch, skb);
+       kfree_skb(skb);
        flow->dropped++;
        return idx;
 }