USB: sierra: fix memory leak in probe error path

commit 084817d7 upstream.

Move interface data allocation to attach so that it is deallocated on
errors in usb-serial probe.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/usb/serial/sierra.c

@@ -171,7 +171,6 @@ static int sierra_probe(struct usb_serial *serial,
 {
 	int result = 0;
 	struct usb_device *udev;
-	struct sierra_intf_private *data;
 	u8 ifnum;
 
 	udev = serial->dev;
@@ -199,11 +198,6 @@ static int sierra_probe(struct usb_serial *serial,
 		return -ENODEV;
 	}
 
-	data = serial->private = kzalloc(sizeof(struct sierra_intf_private), GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-	spin_lock_init(&data->susp_lock);
-
 	return result;
 }
 
@@ -915,6 +909,7 @@ static void sierra_dtr_rts(struct usb_serial_port *port, int on)
 static int sierra_startup(struct usb_serial *serial)
 {
 	struct usb_serial_port *port;
+	struct sierra_intf_private *intfdata;
 	struct sierra_port_private *portdata;
 	struct sierra_iface_info *himemoryp = NULL;
 	int i;
@@ -922,6 +917,14 @@ static int sierra_startup(struct usb_serial *serial)
 
 	dev_dbg(&serial->dev->dev, "%s\n", __func__);
 
+	intfdata = kzalloc(sizeof(*intfdata), GFP_KERNEL);
+	if (!intfdata)
+		return -ENOMEM;
+
+	spin_lock_init(&intfdata->susp_lock);
+
+	usb_set_serial_data(serial, intfdata);
+
 	/* Set Device mode to D0 */
 	sierra_set_power_state(serial->dev, 0x0000);
 
@@ -979,6 +982,7 @@ static int sierra_startup(struct usb_serial *serial)
 		portdata = usb_get_serial_port_data(serial->port[i]);
 		kfree(portdata);
 	}
+	kfree(intfdata);
 
 	return -ENOMEM;
 }