net: dsa: b53: Use strlcpy() for ethtool::get_strings

ffainelli · davem330 · commit cd526676de1e · 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: 967dd82 ("net: dsa: b53: Add support for Broadcom RoboSwitch") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
@@ -814,8 +814,8 @@ void b53_get_strings(struct dsa_switch *ds, int port, uint8_t *data)
 	unsigned int i;
 
 	for (i = 0; i < mib_size; i++)
-		memcpy(data + i * ETH_GSTRING_LEN,
-		       mibs[i].name, ETH_GSTRING_LEN);
+		strlcpy(data + i * ETH_GSTRING_LEN,
+			mibs[i].name, ETH_GSTRING_LEN);
 }
 EXPORT_SYMBOL(b53_get_strings);
 

Original file line number	Diff line number	Diff line change
`@@ -814,8 +814,8 @@ void b53_get_strings(struct dsa_switch ds, int port, uint8_t data)`
`814`	`814`	`unsigned int i;`
`815`	`815`
`816`	`816`	`for (i = 0; i < mib_size; i++)`
`817`		`- memcpy(data + i * ETH_GSTRING_LEN,`
`818`		`- mibs[i].name, ETH_GSTRING_LEN);`
	`817`	`+ strlcpy(data + i * ETH_GSTRING_LEN,`
	`818`	`+ mibs[i].name, ETH_GSTRING_LEN);`
`819`	`819`	`}`
`820`	`820`	`EXPORT_SYMBOL(b53_get_strings);`
`821`	`821`