From 841cae881066f0dd38d15a90cfcf245b0db9fc73 Mon Sep 17 00:00:00 2001 From: Hangyu Hua Date: Mon, 3 Jun 2024 15:13:03 +0800 Subject: [PATCH] UPSTREAM: net: sched: sch_multiq: fix possible OOB write in multiq_tune() [ Upstream commit affc18fdc694190ca7575b9a86632a73b9fe043d ] q->bands will be assigned to qopt->bands to execute subsequent code logic after kmalloc. So the old q->bands should not be used in kmalloc. Otherwise, an out-of-bounds write will occur. Bug: 349777785 Fixes: c2999f7fb05b ("net: sched: multiq: don't call qdisc_put() while holding tree lock") Signed-off-by: Hangyu Hua Acked-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin (cherry picked from commit 0f208fad86631e005754606c3ec80c0d44a11882) Signed-off-by: Lee Jones Change-Id: Iec8413c39878596795420ae58bbe6974890cf2de --- net/sched/sch_multiq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/sched/sch_multiq.c b/net/sched/sch_multiq.c index 75c9c860182b..0d6649d937c9 100644 --- a/net/sched/sch_multiq.c +++ b/net/sched/sch_multiq.c @@ -185,7 +185,7 @@ static int multiq_tune(struct Qdisc *sch, struct nlattr *opt, qopt->bands = qdisc_dev(sch)->real_num_tx_queues; - removed = kmalloc(sizeof(*removed) * (q->max_bands - q->bands), + removed = kmalloc(sizeof(*removed) * (q->max_bands - qopt->bands), GFP_KERNEL); if (!removed) return -ENOMEM;