From 9261a5cc51208ab5aff5e8fdfb99ea8f4c7a71d1 Mon Sep 17 00:00:00 2001
From: Florian Fainelli <f.fainelli@gmail.com>
Date: Fri, 2 Mar 2018 15:08:36 -0800
Subject: [PATCH 21/24] net: dsa: b53: Use strlcpy() for ethtool::get_strings
Git-commit: cd526676de1ece03a8ea7cea726cf879a2dba2b8 
Patch-mainline: v4.16-rc7
References: git-fixes

Our statistics strings are allocated at initialization without being
bound to a specific size, yet, we would copy ETH_GSTRING_LEN bytes using
memcpy() which would create out of bounds accesses, this was flagged by
KASAN. Replace this with strlcpy() to make sure we are bound the source
buffer size and we also always NUL-terminate strings.

Fixes: 967dd82ffc52 ("net: dsa: b53: Add support for Broadcom RoboSwitch")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
 drivers/net/dsa/b53/b53_common.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
index cd9a7df06878..fe19afadc2f3 100644
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -753,8 +753,8 @@ void b53_get_strings(struct dsa_switch *ds, int port, uint8_t *data)
 	unsigned int i;
 
 	for (i = 0; i < mib_size; i++)
-		memcpy(data + i * ETH_GSTRING_LEN,
-		       mibs[i].name, ETH_GSTRING_LEN);
+		strlcpy(data + i * ETH_GSTRING_LEN,
+			mibs[i].name, ETH_GSTRING_LEN);
 }
 EXPORT_SYMBOL(b53_get_strings);
 
-- 
2.16.4