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, 5 insertions, 8 deletions

diff --git a/drivers/usb/serial/mct_u232.c b/drivers/usb/serial/mct_u232.c
index 873795548fc0..d8825e159aa5 100644
--- a/drivers/usb/serial/mct_u232.c
+++ b/drivers/usb/serial/mct_u232.c
@@ -92,7 +92,7 @@ static int debug;
  * Function prototypes
  */
 static int  mct_u232_startup(struct usb_serial *serial);
-static void mct_u232_shutdown(struct usb_serial *serial);
+static void mct_u232_release(struct usb_serial *serial);
 static int  mct_u232_open(struct tty_struct *tty,
                         struct usb_serial_port *port, struct file *filp);
 static void mct_u232_close(struct usb_serial_port *port);
@@ -149,7 +149,7 @@ static struct usb_serial_driver mct_u232_device = {
         .tiocmget =          mct_u232_tiocmget,
         .tiocmset =          mct_u232_tiocmset,
         .attach =            mct_u232_startup,
-        .shutdown =          mct_u232_shutdown,
+        .release =           mct_u232_release,
 };
 
 
@@ -407,7 +407,7 @@ static int mct_u232_startup(struct usb_serial *serial)
 } /* mct_u232_startup */
 
 
-static void mct_u232_shutdown(struct usb_serial *serial)
+static void mct_u232_release(struct usb_serial *serial)
 {
         struct mct_u232_private *priv;
         int i;
@@ -417,12 +417,9 @@ static void mct_u232_shutdown(struct usb_serial *serial)
         for (i = 0; i < serial->num_ports; ++i) {
                 /* My special items, the standard routines free my urbs */
                 priv = usb_get_serial_port_data(serial->port[i]);
-                if (priv) {
-                        usb_set_serial_port_data(serial->port[i], NULL);
-                        kfree(priv);
-                }
+                kfree(priv);
         }
-} /* mct_u232_shutdown */
+} /* mct_u232_release */
 
 static int  mct_u232_open(struct tty_struct *tty,
                         struct usb_serial_port *port, struct file *filp)