[PATCH AUTOSEL 4.19 572/671] net: sched: cbs: Avoid division by zero when calculating the port rate
From: Sasha Levin <sashal@kernel.org>
Date: 2020-01-16 18:38:54
Also in:
lkml, stable
Subsystem:
cbs/etf/taprio qdiscs, networking [general], tc subsystem, the rest · Maintainers:
Vinicius Costa Gomes, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Jamal Hadi Salim, Jiri Pirko, Linus Torvalds
From: Vladimir Oltean <olteanv@gmail.com>
[ Upstream commit 83c8c3cf45163f0c823db37be6ab04dfcf8ac751 ]
As explained in the "net: sched: taprio: Avoid division by zero on
invalid link speed" commit, it is legal for the ethtool API to return
zero as a link speed. So guard against it to ensure we don't perform a
division by zero in kernel.
Fixes: e0a7683d30e9 ("net/sched: cbs: fix port_rate miscalculation")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/sched/sch_cbs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/sched/sch_cbs.c b/net/sched/sch_cbs.c
index 289f66b9238d..940e72d6db18 100644
--- a/net/sched/sch_cbs.c
+++ b/net/sched/sch_cbs.c@@ -310,7 +310,7 @@ static void cbs_set_port_rate(struct net_device *dev, struct cbs_sched_data *q) if (err < 0) goto skip; - if (ecmd.base.speed != SPEED_UNKNOWN) + if (ecmd.base.speed && ecmd.base.speed != SPEED_UNKNOWN) speed = ecmd.base.speed; skip:
--
2.20.1