USB: metro-usb: fix port-data memory leak

Fix port-data memory leak by moving port data allocation and
deallocation to 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.

Note that the call to metrousb_clean (close) in shutdown was redundant.

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>

1 files changed, 13 insertions, 37 deletions

diff --git a/drivers/usb/serial/metro-usb.c b/drivers/usb/serial/metro-usb.c
index 0b257ddffbdb..25cb97c25ad4 100644
--- a/drivers/usb/serial/metro-usb.c
+++ b/drivers/usb/serial/metro-usb.c
@@ -271,51 +271,27 @@ static int metrousb_set_modem_ctrl(struct usb_serial *serial, unsigned int contr
         return retval;
 }
 
-static void metrousb_shutdown(struct usb_serial *serial)
+static int metrousb_port_probe(struct usb_serial_port *port)
 {
-        int i = 0;
+        struct metrousb_private *metro_priv;
 
-        dev_dbg(&serial->dev->dev, "%s\n", __func__);
+        metro_priv = kzalloc(sizeof(*metro_priv), GFP_KERNEL);
+        if (!metro_priv)
+                return -ENOMEM;
 
-        /* Stop reading and writing on all ports. */
-        for (i = 0; i < serial->num_ports; ++i) {
-                /* Close any open urbs. */
-                metrousb_cleanup(serial->port[i]);
+        spin_lock_init(&metro_priv->lock);
 
-                /* Free memory. */
-                kfree(usb_get_serial_port_data(serial->port[i]));
-                usb_set_serial_port_data(serial->port[i], NULL);
+        usb_set_serial_port_data(port, metro_priv);
 
-                dev_dbg(&serial->dev->dev, "%s - freed port number=%d\n",
-                        __func__, serial->port[i]->number);
-        }
+        return 0;
 }
 
-static int metrousb_startup(struct usb_serial *serial)
+static int metrousb_port_remove(struct usb_serial_port *port)
 {
         struct metrousb_private *metro_priv;
-        struct usb_serial_port *port;
-        int i = 0;
-
-        dev_dbg(&serial->dev->dev, "%s\n", __func__);
 
-        /* Loop through the serial ports setting up the private structures.
-         * Currently we only use one port. */
-        for (i = 0; i < serial->num_ports; ++i) {
-                port = serial->port[i];
-
-                /* Declare memory. */
-                metro_priv = kzalloc(sizeof(struct metrousb_private), GFP_KERNEL);
-                if (!metro_priv)
-                        return -ENOMEM;
-
-                /* Initialize memory. */
-                spin_lock_init(&metro_priv->lock);
-                usb_set_serial_port_data(port, metro_priv);
-
-                dev_dbg(&serial->dev->dev, "%s - port number=%d\n ",
-                        __func__, port->number);
-        }
+        metro_priv = usb_get_serial_port_data(port);
+        kfree(metro_priv);
 
         return 0;
 }
@@ -414,8 +390,8 @@ static struct usb_serial_driver metrousb_device = {
         .close                  = metrousb_cleanup,
         .read_int_callback      = metrousb_read_int_callback,
         .write_int_callback     = metrousb_write_int_callback,
-        .attach                 = metrousb_startup,
-        .release                = metrousb_shutdown,
+        .port_probe             = metrousb_port_probe,
+        .port_remove            = metrousb_port_remove,
         .throttle               = metrousb_throttle,
         .unthrottle             = metrousb_unthrottle,
         .tiocmget               = metrousb_tiocmget,