Commit 3725a269 authored Feb 03, 2015 by Kenneth Klette Jonassen Committed by David S. Miller Feb 04, 2015

pkt_sched: fq: avoid hang when quantum 0



Configuring fq with quantum 0 hangs the system, presumably because of a
non-interruptible infinite loop. Either way quantum 0 does not make sense.

Reproduce with:
sudo tc qdisc add dev lo root fq quantum 0 initial_quantum 0
ping 127.0.0.1

Signed-off-by: Kenneth Klette Jonassen <kennetkl@ifi.uio.no>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent db27ebb1

net/sched/sch_fq.c

+8 −2

Original line number	Diff line number	Diff line
		@@ -670,8 +670,14 @@ static int fq_change(struct Qdisc sch, struct nlattr opt)
		if (tb[TCA_FQ_FLOW_PLIMIT])
		q->flow_plimit = nla_get_u32(tb[TCA_FQ_FLOW_PLIMIT]);

		if (tb[TCA_FQ_QUANTUM])
		q->quantum = nla_get_u32(tb[TCA_FQ_QUANTUM]);
		if (tb[TCA_FQ_QUANTUM]) {
		u32 quantum = nla_get_u32(tb[TCA_FQ_QUANTUM]);

		if (quantum > 0)
		q->quantum = quantum;
		else
		err = -EINVAL;
		}

		if (tb[TCA_FQ_INITIAL_QUANTUM])
		q->initial_quantum = nla_get_u32(tb[TCA_FQ_INITIAL_QUANTUM]);