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/symbolserial.c b/drivers/usb/serial/symbolserial.c
index 8b07ebc6baeb..6157fac9366b 100644
--- a/drivers/usb/serial/symbolserial.c
+++ b/drivers/usb/serial/symbolserial.c
@@ -267,7 +267,7 @@ error:
         return retval;
 }
 
-static void symbol_shutdown(struct usb_serial *serial)
+static void symbol_disconnect(struct usb_serial *serial)
 {
         struct symbol_private *priv = usb_get_serial_data(serial);
 
@@ -275,9 +275,16 @@ static void symbol_shutdown(struct usb_serial *serial)
 
         usb_kill_urb(priv->int_urb);
         usb_free_urb(priv->int_urb);
+}
+
+static void symbol_release(struct usb_serial *serial)
+{
+        struct symbol_private *priv = usb_get_serial_data(serial);
+
+        dbg("%s", __func__);
+
         kfree(priv->int_buffer);
         kfree(priv);
-        usb_set_serial_data(serial, NULL);
 }
 
 static struct usb_driver symbol_driver = {
@@ -299,7 +306,8 @@ static struct usb_serial_driver symbol_device = {
         .attach =               symbol_startup,
         .open =                 symbol_open,
         .close =                symbol_close,
-        .shutdown =             symbol_shutdown,
+        .disconnect =           symbol_disconnect,
+        .release =              symbol_release,
         .throttle =             symbol_throttle,
         .unthrottle =           symbol_unthrottle,
 };