[ 056/101] USB: metro-usb: fix port-data memory leak

From: Greg Kroah-Hartman
Date: Mon Oct 29 2012 - 18:08:15 EST


3.6-stable review patch. If anyone has any objections, please let me know.

------------------

From: Johan Hovold <jhovold@xxxxxxxxx>

commit 50dde8686eec41bf3d7cbec7a6f76c073ab01903 upstream.

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.

Signed-off-by: Johan Hovold <jhovold@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/usb/serial/metro-usb.c | 50 ++++++++++-------------------------------
1 file changed, 13 insertions(+), 37 deletions(-)

--- a/drivers/usb/serial/metro-usb.c
+++ b/drivers/usb/serial/metro-usb.c
@@ -280,51 +280,27 @@ static int metrousb_set_modem_ctrl(struc
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;
}
@@ -423,8 +399,8 @@ static struct usb_serial_driver metrousb
.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,


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