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, 12 insertions, 5 deletions

diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index a38971cc3731..575816e6ba37 100644
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -51,7 +51,8 @@ static void option_close(struct usb_serial_port *port);
 static void option_dtr_rts(struct usb_serial_port *port, int on);
 
 static int  option_startup(struct usb_serial *serial);
-static void option_shutdown(struct usb_serial *serial);
+static void option_disconnect(struct usb_serial *serial);
+static void option_release(struct usb_serial *serial);
 static int  option_write_room(struct tty_struct *tty);
 
 static void option_instat_callback(struct urb *urb);
@@ -568,7 +569,8 @@ static struct usb_serial_driver option_1port_device = {
         .tiocmget          = option_tiocmget,
         .tiocmset          = option_tiocmset,
         .attach            = option_startup,
-        .shutdown          = option_shutdown,
+        .disconnect        = option_disconnect,
+        .release           = option_release,
         .read_int_callback = option_instat_callback,
         .suspend           = option_suspend,
         .resume            = option_resume,
@@ -1149,7 +1151,14 @@ static void stop_read_write_urbs(struct usb_serial *serial)
         }
 }
 
-static void option_shutdown(struct usb_serial *serial)
+static void option_disconnect(struct usb_serial *serial)
+{
+        dbg("%s", __func__);
+
+        stop_read_write_urbs(serial);
+}
+
+static void option_release(struct usb_serial *serial)
 {
         int i, j;
         struct usb_serial_port *port;
@@ -1157,8 +1166,6 @@ static void option_shutdown(struct usb_serial *serial)
 
         dbg("%s", __func__);
 
-        stop_read_write_urbs(serial);
-
         /* Now free them */
         for (i = 0; i < serial->num_ports; ++i) {
                 port = serial->port[i];