5.4-stable review patch. If anyone has any objections, please let me know.
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From: Hangyu Hua hbh25y@gmail.com
[ 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.
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 --- 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 1330ad2249317..b822d3e74637d 100644 --- a/net/sched/sch_multiq.c +++ b/net/sched/sch_multiq.c @@ -186,7 +186,7 @@ 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;