From ba51edae4b38ed49fafd7276440b43faf5cde29e Mon Sep 17 00:00:00 2001
From: Nogah Frankel <nogahf@mellanox.com>
Date: Mon, 4 Dec 2017 13:31:10 +0200
Subject: [PATCH] net_sched: red: Avoid devision by zero

[ Upstream commit 5c472203421ab4f928aa1ae9e1dbcfdd80324148 ]

Do not allow delta value to be zero since it is used as a divisor.

Fixes: 8af2a218de38 ("sch_red: Adaptative RED AQM")
Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/net/red.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/net/red.h b/include/net/red.h
index 76e0b5f922c6..ba5039418a93 100644
--- a/include/net/red.h
+++ b/include/net/red.h
@@ -178,7 +178,7 @@ static inline void red_set_parms(struct red_parms *p,
 	p->qth_max	= qth_max << Wlog;
 	p->Wlog		= Wlog;
 	p->Plog		= Plog;
-	if (delta < 0)
+	if (delta <= 0)
 		delta = 1;
 	p->qth_delta	= delta;
 	if (!max_P) {