USB: sierra: 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 also that urb-count for multi-port interfaces has not been changed
even though the usb-serial port number is now determined from the port
and interface minor numbers.

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, 58 insertions, 67 deletions

diff --git a/drivers/usb/serial/sierra.c b/drivers/usb/serial/sierra.c
index bb2ecaf3296b..270860f6bb2a 100644
--- a/drivers/usb/serial/sierra.c
+++ b/drivers/usb/serial/sierra.c
@@ -878,12 +878,7 @@ 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;
-        u8 ifnum;
 
         intfdata = kzalloc(sizeof(*intfdata), GFP_KERNEL);
         if (!intfdata)
@@ -900,77 +895,71 @@ static int sierra_startup(struct usb_serial *serial)
         if (nmea)
                 sierra_vsc_set_nmea(serial->dev, 1);
 
-        /* Now setup per port private data */
-        for (i = 0; i < serial->num_ports; i++) {
-                port = serial->port[i];
-                portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
-                if (!portdata) {
-                        dev_dbg(&port->dev, "%s: kmalloc for "
-                                "sierra_port_private (%d) failed!\n",
-                                __func__, i);
-                        goto err;
-                }
-                spin_lock_init(&portdata->lock);
-                init_usb_anchor(&portdata->active);
-                init_usb_anchor(&portdata->delayed);
-                ifnum = i;
-                /* Assume low memory requirements */
-                portdata->num_out_urbs = N_OUT_URB;
-                portdata->num_in_urbs  = N_IN_URB;
-
-                /* Determine actual memory requirements */
-                if (serial->num_ports == 1) {
-                        /* Get interface number for composite device */
-                        ifnum = sierra_calc_interface(serial);
-                        himemoryp =
-                            (struct sierra_iface_info *)&typeB_interface_list;
-                        if (is_himemory(ifnum, himemoryp)) {
-                                portdata->num_out_urbs = N_OUT_URB_HM;
-                                portdata->num_in_urbs  = N_IN_URB_HM;
-                        }
-                }
-                else {
-                        himemoryp =
-                            (struct sierra_iface_info *)&typeA_interface_list;
-                        if (is_himemory(i, himemoryp)) {
-                                portdata->num_out_urbs = N_OUT_URB_HM;
-                                portdata->num_in_urbs  = N_IN_URB_HM;
-                        }
-                }
-                dev_dbg(&serial->dev->dev,
-                        "Memory usage (urbs) interface #%d, in=%d, out=%d\n",
-                        ifnum,portdata->num_in_urbs, portdata->num_out_urbs );
-                /* Set the port private data pointer */
-                usb_set_serial_port_data(port, portdata);
+        return 0;
+}
+
+static void sierra_release(struct usb_serial *serial)
+{
+        struct sierra_intf_private *intfdata;
+
+        intfdata = usb_get_serial_data(serial);
+        kfree(intfdata);
+}
+
+static int sierra_port_probe(struct usb_serial_port *port)
+{
+        struct usb_serial *serial = port->serial;
+        struct sierra_port_private *portdata;
+        const struct sierra_iface_info *himemoryp;
+        u8 ifnum;
+
+        portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
+        if (!portdata)
+                return -ENOMEM;
+
+        spin_lock_init(&portdata->lock);
+        init_usb_anchor(&portdata->active);
+        init_usb_anchor(&portdata->delayed);
+
+        /* Assume low memory requirements */
+        portdata->num_out_urbs = N_OUT_URB;
+        portdata->num_in_urbs  = N_IN_URB;
+
+        /* Determine actual memory requirements */
+        if (serial->num_ports == 1) {
+                /* Get interface number for composite device */
+                ifnum = sierra_calc_interface(serial);
+                himemoryp = &typeB_interface_list;
+        } else {
+                /* This is really the usb-serial port number of the interface
+                 * rather than the interface number.
+                 */
+                ifnum = port->number - serial->minor;
+                himemoryp = &typeA_interface_list;
         }
 
-        return 0;
-err:
-        for (--i; i >= 0; --i) {
-                portdata = usb_get_serial_port_data(serial->port[i]);
-                kfree(portdata);
+        if (is_himemory(ifnum, himemoryp)) {
+                portdata->num_out_urbs = N_OUT_URB_HM;
+                portdata->num_in_urbs  = N_IN_URB_HM;
         }
-        kfree(intfdata);
 
-        return -ENOMEM;
+        dev_dbg(&port->dev,
+                        "Memory usage (urbs) interface #%d, in=%d, out=%d\n",
+                        ifnum, portdata->num_in_urbs, portdata->num_out_urbs);
+
+        usb_set_serial_port_data(port, portdata);
+
+        return 0;
 }
 
-static void sierra_release(struct usb_serial *serial)
+static int sierra_port_remove(struct usb_serial_port *port)
 {
-        int i;
-        struct usb_serial_port *port;
         struct sierra_port_private *portdata;
 
-        for (i = 0; i < serial->num_ports; ++i) {
-                port = serial->port[i];
-                if (!port)
-                        continue;
-                portdata = usb_get_serial_port_data(port);
-                if (!portdata)
-                        continue;
-                kfree(portdata);
-        }
-        kfree(serial->private);
+        portdata = usb_get_serial_port_data(port);
+        kfree(portdata);
+
+        return 0;
 }
 
 #ifdef CONFIG_PM
@@ -1074,6 +1063,8 @@ static struct usb_serial_driver sierra_device = {
         .tiocmset          = sierra_tiocmset,
         .attach            = sierra_startup,
         .release           = sierra_release,
+        .port_probe        = sierra_port_probe,
+        .port_remove       = sierra_port_remove,
         .suspend           = sierra_suspend,
         .resume            = sierra_resume,
         .read_int_callback = sierra_instat_callback,