[PATCH 4.4 18/43] can: usb_8dev: fix use-after-free on disconnect

From: Greg Kroah-Hartman
Date: Mon Nov 11 2019 - 13:30:22 EST


From: Johan Hovold <johan@xxxxxxxxxx>

commit 3759739426186a924675651b388d1c3963c5710e upstream.

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

Fixes: 0024d8ad1639 ("can: usb_8dev: Add support for USB2CAN interface from 8 devices")
Cc: stable <stable@xxxxxxxxxxxxxxx> # 3.9
Cc: Bernd Krumboeck <b.krumboeck@xxxxxxxxx>
Cc: Wolfgang Grandegger <wg@xxxxxxxxxxxxxx>
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/usb_8dev.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/drivers/net/can/usb/usb_8dev.c
+++ b/drivers/net/can/usb/usb_8dev.c
@@ -1010,9 +1010,8 @@ static void usb_8dev_disconnect(struct u
netdev_info(priv->netdev, "device disconnected\n");

unregister_netdev(priv->netdev);
- free_candev(priv->netdev);
-
unlink_all_urbs(priv);
+ free_candev(priv->netdev);
}

}