From: Dan Carpenter <dan.carpenter@oracle.com> stable inclusion from stable-v4.19.265 commit e877f8fa49fbccc63cb2df2e9179bddc695b825a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IC5BSK CVE: CVE-2022-49921 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 8bdc2acd420c6f3dd1f1c78750ec989f02a1e2b9 ] We can't use "skb" again after passing it to qdisc_enqueue(). This is basically identical to commit 2f09707d0c97 ("sch_sfb: Also store skb len before calling child enqueue"). Fixes: d7f4f332f082 ("sch_red: update backlog as well") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com> --- net/sched/sch_red.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c index a3dc211..302d11c 100644 --- a/net/sched/sch_red.c +++ b/net/sched/sch_red.c @@ -63,6 +63,7 @@ static int red_enqueue(struct sk_buff *skb, struct Qdisc *sch, { struct red_sched_data *q = qdisc_priv(sch); struct Qdisc *child = q->qdisc; + unsigned int len; int ret; q->vars.qavg = red_calc_qavg(&q->parms, @@ -98,9 +99,10 @@ static int red_enqueue(struct sk_buff *skb, struct Qdisc *sch, break; } + len = qdisc_pkt_len(skb); ret = qdisc_enqueue(skb, child, to_free); if (likely(ret == NET_XMIT_SUCCESS)) { - qdisc_qstats_backlog_inc(sch, skb); + sch->qstats.backlog += len; sch->q.qlen++; } else if (net_xmit_drop_count(ret)) { q->stats.pdrop++; -- 2.9.5