net: phy: micrel: Use strlcpy() for ethtool::get_strings

commit 55f53567afe5f0cd2fd9e006b174c08c31c466f8 upstream.

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: 2b2427d06426 ("phy: micrel: Add ethtool statistics counters")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index 5be7fc354e338e86c859daf13d4be0f1043d4842..ef5e5b621ec594a8f2cb8bca12247292d25c46ee 100644 (file)
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -674,8 +674,8 @@ static void kszphy_get_strings(struct phy_device *phydev, u8 *data)
        int i;
 
        for (i = 0; i < ARRAY_SIZE(kszphy_hw_stats); i++) {
-               memcpy(data + i * ETH_GSTRING_LEN,
-                      kszphy_hw_stats[i].string, ETH_GSTRING_LEN);
+               strlcpy(data + i * ETH_GSTRING_LEN,
+                       kszphy_hw_stats[i].string, ETH_GSTRING_LEN);
        }
 }