net: phy: broadcom: 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: 820ee17b8d3b ("net: phy: broadcom: Add support code for reading PHY 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/bcm-phy-lib.c b/drivers/net/phy/bcm-phy-lib.c
index 171010eb4d9c5c36da0be9888fb75cc54e136768..5ad130c3da43c869b39dc8ec83ec6795aa82be7d 100644 (file)
--- a/drivers/net/phy/bcm-phy-lib.c
+++ b/drivers/net/phy/bcm-phy-lib.c
@@ -341,8 +341,8 @@ void bcm_phy_get_strings(struct phy_device *phydev, u8 *data)
        unsigned int i;
 
        for (i = 0; i < ARRAY_SIZE(bcm_phy_hw_stats); i++)
-               memcpy(data + i * ETH_GSTRING_LEN,
-                      bcm_phy_hw_stats[i].string, ETH_GSTRING_LEN);
+               strlcpy(data + i * ETH_GSTRING_LEN,
+                       bcm_phy_hw_stats[i].string, ETH_GSTRING_LEN);
 }
 EXPORT_SYMBOL_GPL(bcm_phy_get_strings);