| Message ID | Y1vvnBnSVl976Pt3@kili (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 8bdc2acd420c6f3dd1f1c78750ec989f02a1e2b9 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] net: sched: Fix use after free in red_enqueue() | expand |
On Fri, Oct 28, 2022 at 8:05 AM Dan Carpenter <dan.carpenter@oracle.com> wrote: > > 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") Reviewed-by: Eric Dumazet <edumazet@google.com>
Hello: This patch was applied to netdev/net.git (master) by David S. Miller <davem@davemloft.net>: On Fri, 28 Oct 2022 18:05:00 +0300 you wrote: > 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> > > [...] Here is the summary with links: - [net] net: sched: Fix use after free in red_enqueue() https://git.kernel.org/netdev/net/c/8bdc2acd420c You are awesome, thank you!
diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c index a5a401f93c1a..98129324e157 100644 --- a/net/sched/sch_red.c +++ b/net/sched/sch_red.c @@ -72,6 +72,7 @@ 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, @@ -126,9 +127,10 @@ 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++;
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> --- Applies to net. net/sched/sch_red.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)