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

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>

diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index 0f45310300f667bab84655d301d64eb8196ae128..49be85afbea9369563336994462651505155ce0a 100644 (file)
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -664,8 +664,8 @@ 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);
        }
 }