USB: f81232: fix port-data memory leak

Fix port-data memory leak by replacing attach and release with
port_probe and port_remove.

Since commit 0998d0631001288 (device-core: Ensure drvdata = NULL when no
driver is bound) the port private data is no longer freed at release as
it is no longer accessible.

Compile-only tested.

Cc: <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/serial/f81232.c

@@ -318,39 +318,30 @@ static int f81232_ioctl(struct tty_struct *tty,
 	return -ENOIOCTLCMD;
 }
 
-static int f81232_startup(struct usb_serial *serial)
+static int f81232_port_probe(struct usb_serial_port *port)
 {
 	struct f81232_private *priv;
-	int i;
 
-	for (i = 0; i < serial->num_ports; ++i) {
-		priv = kzalloc(sizeof(struct f81232_private), GFP_KERNEL);
-		if (!priv)
-			goto cleanup;
-		spin_lock_init(&priv->lock);
-		init_waitqueue_head(&priv->delta_msr_wait);
-		usb_set_serial_port_data(serial->port[i], priv);
-	}
-	return 0;
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
 
-cleanup:
-	for (--i; i >= 0; --i) {
-		priv = usb_get_serial_port_data(serial->port[i]);
-		kfree(priv);
-		usb_set_serial_port_data(serial->port[i], NULL);
-	}
-	return -ENOMEM;
+	spin_lock_init(&priv->lock);
+	init_waitqueue_head(&priv->delta_msr_wait);
+
+	usb_set_serial_port_data(port, priv);
+
+	return 0;
 }
 
-static void f81232_release(struct usb_serial *serial)
+static int f81232_port_remove(struct usb_serial_port *port)
 {
-	int i;
 	struct f81232_private *priv;
 
-	for (i = 0; i < serial->num_ports; ++i) {
-		priv = usb_get_serial_port_data(serial->port[i]);
-		kfree(priv);
-	}
+	priv = usb_get_serial_port_data(port);
+	kfree(priv);
+
+	return 0;
 }
 
 static struct usb_serial_driver f81232_device = {
@@ -373,8 +364,8 @@ static struct usb_serial_driver f81232_device = {
 	.tiocmset =		f81232_tiocmset,
 	.process_read_urb =	f81232_process_read_urb,
 	.read_int_callback =	f81232_read_int_callback,
-	.attach =		f81232_startup,
-	.release =		f81232_release,
+	.port_probe =		f81232_port_probe,
+	.port_remove =		f81232_port_remove,
 };
 
 static struct usb_serial_driver * const serial_drivers[] = {