hso: fix for crash when unplugging the device

Changed the order in which things are freed. This fixes an oops when
unplugging the device while network traffic is ongoing.
Signed-off-by: Jan Dumon <j.dumon@option.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/usb/hso.c

@@ -5,6 +5,7 @@
  *  Copyright (C) 2008 Option International
  *                     Filip Aben <f.aben@option.com>
  *                     Denis Joseph Barrow <d.barow@option.com>
+ *                     Jan Dumon <j.dumon@option.com>
  *  Copyright (C) 2007 Andrew Bird (Sphere Systems Ltd)
  *  			<ajb@spheresystems.co.uk>
  *  Copyright (C) 2008 Greg Kroah-Hartman <gregkh@suse.de>
@@ -2417,20 +2418,22 @@ static void hso_free_net_device(struct hso_device *hso_dev)
 	if (!hso_net)
 		return;
 
+	remove_net_device(hso_net->parent);
+
+	if (hso_net->net) {
+		unregister_netdev(hso_net->net);
+		free_netdev(hso_net->net);
+	}
+
 	/* start freeing */
 	for (i = 0; i < MUX_BULK_RX_BUF_COUNT; i++) {
 		usb_free_urb(hso_net->mux_bulk_rx_urb_pool[i]);
 		kfree(hso_net->mux_bulk_rx_buf_pool[i]);
+		hso_net->mux_bulk_rx_buf_pool[i] = NULL;
 	}
 	usb_free_urb(hso_net->mux_bulk_tx_urb);
 	kfree(hso_net->mux_bulk_tx_buf);
-
-	remove_net_device(hso_net->parent);
-
-	if (hso_net->net) {
-		unregister_netdev(hso_net->net);
-		free_netdev(hso_net->net);
-	}
+	hso_net->mux_bulk_tx_buf = NULL;
 
 	kfree(hso_dev);
 }
@@ -2620,12 +2623,12 @@ static void hso_free_tiomget(struct hso_serial *serial)
 {
 	struct hso_tiocmget *tiocmget = serial->tiocmget;
 	if (tiocmget) {
-		kfree(tiocmget);
 		if (tiocmget->urb) {
 			usb_free_urb(tiocmget->urb);
 			tiocmget->urb = NULL;
 		}
 		serial->tiocmget = NULL;
+		kfree(tiocmget);
 
 	}
 }