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, 4 insertions, 8 deletions

diff --git a/drivers/usb/serial/kobil_sct.c b/drivers/usb/serial/kobil_sct.c
index 6b570498287f..6db0e561f680 100644
--- a/drivers/usb/serial/kobil_sct.c
+++ b/drivers/usb/serial/kobil_sct.c
@@ -69,7 +69,7 @@ static int debug;
 
 /* Function prototypes */
 static int  kobil_startup(struct usb_serial *serial);
-static void kobil_shutdown(struct usb_serial *serial);
+static void kobil_release(struct usb_serial *serial);
 static int  kobil_open(struct tty_struct *tty,
                         struct usb_serial_port *port, struct file *filp);
 static void kobil_close(struct usb_serial_port *port);
@@ -117,7 +117,7 @@ static struct usb_serial_driver kobil_device = {
         .id_table =             id_table,
         .num_ports =            1,
         .attach =               kobil_startup,
-        .shutdown =             kobil_shutdown,
+        .release =              kobil_release,
         .ioctl =                kobil_ioctl,
         .set_termios =          kobil_set_termios,
         .tiocmget =             kobil_tiocmget,
@@ -201,17 +201,13 @@ static int kobil_startup(struct usb_serial *serial)
 }
 
 
-static void kobil_shutdown(struct usb_serial *serial)
+static void kobil_release(struct usb_serial *serial)
 {
         int i;
         dbg("%s - port %d", __func__, serial->port[0]->number);
 
-        for (i = 0; i < serial->num_ports; ++i) {
-                while (serial->port[i]->port.count > 0)
-                        kobil_close(serial->port[i]);
+        for (i = 0; i < serial->num_ports; ++i)
                 kfree(usb_get_serial_port_data(serial->port[i]));
-                usb_set_serial_port_data(serial->port[i], NULL);
-        }
 }