diff options
| author | Dan Carpenter <dan.carpenter@oracle.com> | 2020-02-05 12:53:30 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-02-06 14:00:12 +0100 |
| commit | 7a02ea65027523386ab4ba4af0ab93497b3073df (patch) | |
| tree | b37ff5686ea87247c68728945fe03d13addb3ef4 | |
| parent | skbuff: fix a data race in skb_queue_len() (diff) | |
| download | linux-7a02ea65027523386ab4ba4af0ab93497b3073df.tar.xz linux-7a02ea65027523386ab4ba4af0ab93497b3073df.zip | |
net: sched: prevent a use after free
The bug is that we call kfree_skb(skb) and then pass "skb" to
qdisc_pkt_len(skb) on the next line, which is a use after free.
Also Cong Wang points out that it's better to delay the actual
frees until we drop the rtnl lock so we should use rtnl_kfree_skbs()
instead of kfree_skb().
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/sched/sch_fq_pie.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/sched/sch_fq_pie.c b/net/sched/sch_fq_pie.c index bbd0dea6b6b9..214657eb3dfd 100644 --- a/net/sched/sch_fq_pie.c +++ b/net/sched/sch_fq_pie.c @@ -349,9 +349,9 @@ static int fq_pie_change(struct Qdisc *sch, struct nlattr *opt, while (sch->q.qlen > sch->limit) { struct sk_buff *skb = fq_pie_qdisc_dequeue(sch); - kfree_skb(skb); len_dropped += qdisc_pkt_len(skb); num_dropped += 1; + rtnl_kfree_skbs(skb, skb); } qdisc_tree_reduce_backlog(sch, num_dropped, len_dropped); |