From cc5418973cc9943c276a5ffef645a20f0aadf596 Mon Sep 17 00:00:00 2001
From: Ilya Maximets <i.maximets@ovn.org>
Date: Sun, 4 Apr 2021 19:50:31 +0200
Subject: [PATCH] openvswitch: fix send of uninitialized stack memory in ct
 limit reply

[ Upstream commit 4d51419d49930be2701c2633ae271b350397c3ca ]

'struct ovs_zone_limit' has more members than initialized in
ovs_ct_limit_get_default_limit().  The rest of the memory is a random
kernel stack content that ends up being sent to userspace.

Fix that by using designated initializer that will clear all
non-specified fields.

Fixes: 11efd5cb04a1 ("openvswitch: Support conntrack zone limit")
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Acked-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/openvswitch/conntrack.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index 96a49aa3a128b7..a11b558813c107 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -2024,10 +2024,10 @@ static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit,
 static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info,
 					  struct sk_buff *reply)
 {
-	struct ovs_zone_limit zone_limit;
-
-	zone_limit.zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE;
-	zone_limit.limit = info->default_limit;
+	struct ovs_zone_limit zone_limit = {
+		.zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE,
+		.limit   = info->default_limit,
+	};
 
 	return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
 }
-- 
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