Re: [patch] net_sched: stack info leak in cbq_dump_wrr()

Joe Perches
2013-07-29T19:44:32Z

On Mon, 2013-07-29 at 22:36 +0300, Dan Carpenter wrote:
> opt.__reserved isn't cleared so we leak a byte of stack information.
[]
> diff --git a/net/sched/sch_cbq.c b/net/sched/sch_cbq.c
[]
> @@ -1469,6 +1469,7 @@ static int cbq_dump_wrr(struct sk_buff *skb, struct cbq_class *cl)
> opt.allot = cl->allot;
> opt.priority = cl->priority + 1;
> opt.cpriority = cl->cpriority + 1;
> + opt.__reserved = 0;
> opt.weight = cl->weight;
> if (nla_put(skb, TCA_CBQ_WRROPT, sizeof(opt), &opt))
> goto nla_put_failure;

Alignment isn't guaranteed here so it'd
probably be better with a memset.