[PATCH 4.4 10/79] ieee802154: atusb: fix use-after-free at disconnect

[Greg Kroah-Hartman]

From: Johan Hovold <johan@xxxxxxxxxx>

commit 7fd25e6fc035f4b04b75bca6d7e8daa069603a76 upstream.

The disconnect callback was accessing the hardware-descriptor private
data after having having freed it.

Fixes: 7490b008d123 ("ieee802154: add support for atusb transceiver")
Cc: stable <stable@xxxxxxxxxxxxxxx>     # 4.2
Cc: Alexander Aring <alex.aring@xxxxxxxxx>
Reported-by: syzbot+f4509a9138a1472e7e80@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Stefan Schmidt <stefan@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/net/ieee802154/atusb.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/net/ieee802154/atusb.c
+++ b/drivers/net/ieee802154/atusb.c
@@ -756,10 +756,11 @@ static void atusb_disconnect(struct usb_
 
 	ieee802154_unregister_hw(atusb->hw);
 
+	usb_put_dev(atusb->usb_dev);
+
 	ieee802154_free_hw(atusb->hw);
 
 	usb_set_intfdata(interface, NULL);
-	usb_put_dev(atusb->usb_dev);
 
 	pr_debug("atusb_disconnect done\n");
 }