diff mbox series

[4.19,585/639] net: sched: cbs: Avoid division by zero when calculating the port rate

Message ID 20200124093202.761623028@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg KH Jan. 24, 2020, 9:32 a.m. UTC 
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 mbox series

Patch

diff --git a/net/sched/sch_cbs.c b/net/sched/sch_cbs.c
index 289f66b9238d3..940e72d6db185 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: