USB: usb-serial: replace shutdown with disconnect, release

This patch (as1254) splits up the shutdown method of usb_serial_driver
into a disconnect and a release method.

The problem is that the usb-serial core was calling shutdown during
disconnect handling, but drivers didn't expect it to be called until
after all the open file references had been closed.  The result was an
oops when the close method tried to use memory that had been
deallocated by shutdown.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 11 insertions, 3 deletions

diff --git a/drivers/usb/serial/opticon.c b/drivers/usb/serial/opticon.c
index c20480aa9755..336bba79ad32 100644
--- a/drivers/usb/serial/opticon.c
+++ b/drivers/usb/serial/opticon.c
@@ -463,7 +463,7 @@ error:
         return retval;
 }
 
-static void opticon_shutdown(struct usb_serial *serial)
+static void opticon_disconnect(struct usb_serial *serial)
 {
         struct opticon_private *priv = usb_get_serial_data(serial);
 
@@ -471,9 +471,16 @@ static void opticon_shutdown(struct usb_serial *serial)
 
         usb_kill_urb(priv->bulk_read_urb);
         usb_free_urb(priv->bulk_read_urb);
+}
+
+static void opticon_release(struct usb_serial *serial)
+{
+        struct opticon_private *priv = usb_get_serial_data(serial);
+
+        dbg("%s", __func__);
+
         kfree(priv->bulk_in_buffer);
         kfree(priv);
-        usb_set_serial_data(serial, NULL);
 }
 
 static int opticon_suspend(struct usb_interface *intf, pm_message_t message)
@@ -524,7 +531,8 @@ static struct usb_serial_driver opticon_device = {
         .close =                opticon_close,
         .write =                opticon_write,
         .write_room =           opticon_write_room,
-        .shutdown =             opticon_shutdown,
+        .disconnect =           opticon_disconnect,
+        .release =              opticon_release,
         .throttle =             opticon_throttle,
         .unthrottle =           opticon_unthrottle,
         .ioctl =                opticon_ioctl,