[PATCH net] pkt_sched: fq: avoid hang when quantum 0
flat view
STALE4283d
From: Kenneth Klette Jonassen <hidden>
Date: 2015-02-03 16:50:16
Subsystem:
networking [general], tc subsystem, the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Jamal Hadi Salim, Jiri Pirko, Linus Torvalds
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 <redacted> --- net/sched/sch_fq.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/net/sched/sch_fq.c b/net/sched/sch_fq.c
index 2a50f5c..313794b 100644
--- a/net/sched/sch_fq.c
+++ b/net/sched/sch_fq.c@@ -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]);
--
1.9.1