[PATCH 4.19 050/125] can: mcba_usb: fix use-after-free on disconnect

From: Greg Kroah-Hartman
Date: Mon Nov 11 2019 - 13:42:53 EST


From: Johan Hovold <johan@xxxxxxxxxx>

commit 4d6636498c41891d0482a914dd570343a838ad79 upstream.

The driver was accessing its driver data after having freed it.

Fixes: 51f3baad7de9 ("can: mcba_usb: Add support for Microchip CAN BUS Analyzer")
Cc: stable <stable@xxxxxxxxxxxxxxx> # 4.12
Cc: Remigiusz KoÅÅÄtaj <remigiusz.kollataj@xxxxxxxxxx>
Reported-by: syzbot+e29b17e5042bbc56fae9@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/can/usb/mcba_usb.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/drivers/net/can/usb/mcba_usb.c
+++ b/drivers/net/can/usb/mcba_usb.c
@@ -887,9 +887,8 @@ static void mcba_usb_disconnect(struct u
netdev_info(priv->netdev, "device disconnected\n");

unregister_candev(priv->netdev);
- free_candev(priv->netdev);
-
mcba_urb_unlink(priv);
+ free_candev(priv->netdev);
}

static struct usb_driver mcba_usb_driver = {