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

ffainelli · davem330 · commit 8a17eefa235f · 2018-03-06T11:12:39.000-05:00
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: 820ee17 ("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
@@ -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);
 

Original file line number	Diff line number	Diff line change
`@@ -341,8 +341,8 @@ void bcm_phy_get_strings(struct phy_device phydev, u8 data)`
`341`	`341`	`unsigned int i;`
`342`	`342`
`343`	`343`	`for (i = 0; i < ARRAY_SIZE(bcm_phy_hw_stats); i++)`
`344`		`- memcpy(data + i * ETH_GSTRING_LEN,`
`345`		`- bcm_phy_hw_stats[i].string, ETH_GSTRING_LEN);`
	`344`	`+ strlcpy(data + i * ETH_GSTRING_LEN,`
	`345`	`+ bcm_phy_hw_stats[i].string, ETH_GSTRING_LEN);`
`346`	`346`	`}`
`347`	`347`	`EXPORT_SYMBOL_GPL(bcm_phy_get_strings);`
`348`	`348`