hwmon: (cros_ec) Prevent read overflow in probe()

The "resp.sensor_name" comes from cros_ec_cmd() and it hasn't necessarily
been NUL terminated. We had not intended to read past "sensor_name_size"
bytes, however, there is a width vs precision bug in the format string.
The format needs to be precision '%.*s' instead of width '%*s'.
Precision prevents an out of bounds read, but width is a no-op.

Fixes: bc3e45258096 ("hwmon: add ChromeOS EC driver")
Signed-off-by: Dan Carpenter <[e-mail]>
Reviewed-by: Guenter Roeck <[e-mail]>
Acked-by: Thomas Weißschuh <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Tzung-Bi Shih <[e-mail]>

drivers/hwmon/cros_ec_hwmon.c

···
 			continue;
 
 		sensor_name_size = strnlen(resp.sensor_name, sizeof(resp.sensor_name));
-		priv->temp_sensor_names[i] = devm_kasprintf(dev, GFP_KERNEL, "%*s",
+		priv->temp_sensor_names[i] = devm_kasprintf(dev, GFP_KERNEL, "%.*s",
 							    (int)sensor_name_size,
 							    resp.sensor_name);
 	}