xhci: Fix list corruption in urb dequeue at host removal

[ Upstream commit 5c82171 ]

xhci driver frees data for all devices, both usb2 and and usb3 the
first time usb_remove_hcd() is called, including td_list and and xhci_ring
structures.

When usb_remove_hcd() is called a second time for the second xhci bus it
will try to dequeue all pending urbs, and touches td_list which is already
freed for that endpoint.

Cc: <[email protected]>
Reported-by: Joe Lawrence <[email protected]>
Tested-by: Joe Lawrence <[email protected]>
Signed-off-by: Mathias Nyman <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>

Author: matnyman

drivers/usb/host/xhci.c

@@ -1559,7 +1559,9 @@ int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 		xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
 				"HW died, freeing TD.");
 		urb_priv = urb->hcpriv;
-		for (i = urb_priv->td_cnt; i < urb_priv->length; i++) {
+		for (i = urb_priv->td_cnt;
+		     i < urb_priv->length && xhci->devs[urb->dev->slot_id];
+		     i++) {
 			td = urb_priv->td[i];
 			if (!list_empty(&td->td_list))
 				list_del_init(&td->td_list);