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 <hbh25y@gmail.com>
Acked-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit 0f208fad86631e005754606c3ec80c0d44a11882)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: Iec8413c39878596795420ae58bbe6974890cf2de
diff --git a/net/sched/sch_multiq.c b/net/sched/sch_multiq.c
index 75c9c86..0d6649d 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;