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 adb38a4ec9ac66c4fd895bd85e4220b9e5944c6e..1704d9e2ca8d1d99d54ac073263675adb2452f30 100644 (file)
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -677,8 +677,8 @@ 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);
        }
 }