net: can: at91_can: world-writable sysfs files

Don't allow everybody to write to mb0_id file.
Signed-off-by: NVasiliy Kulikov <segoon@openwall.com>
Acked-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/can/at91_can.c

@@ -1109,7 +1109,7 @@ static ssize_t at91_sysfs_set_mb0_id(struct device *dev,
 	return ret;
 }
 
-static DEVICE_ATTR(mb0_id, S_IWUGO | S_IRUGO,
+static DEVICE_ATTR(mb0_id, S_IWUSR | S_IRUGO,
 	at91_sysfs_show_mb0_id, at91_sysfs_set_mb0_id);
 
 static struct attribute *at91_sysfs_attrs[] = {