| Message ID | 20240603071303.17986-1-hbh25y@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | affc18fdc694190ca7575b9a86632a73b9fe043d |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: sched: sch_multiq: fix possible OOB write in multiq_tune() | expand |
On Mon, Jun 03, 2024 at 03:13:03PM +0800, Hangyu Hua wrote: > 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> Looks good to me. Acked-by: Cong Wang <cong.wang@bytedance.com> Thanks.
Hello: This patch was applied to netdev/net.git (main) by David S. Miller <davem@davemloft.net>: On Mon, 3 Jun 2024 15:13:03 +0800 you wrote: > 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> > > [...] Here is the summary with links: - net: sched: sch_multiq: fix possible OOB write in multiq_tune() https://git.kernel.org/netdev/net/c/affc18fdc694 You are awesome, thank you!
diff --git a/net/sched/sch_multiq.c b/net/sched/sch_multiq.c index 79e93a19d5fa..06e03f5cd7ce 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;
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> --- net/sched/sch_multiq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)