xhci: Fix race between ep halt and URB cancellation

The halted state of a endpoint cannot be cleared over CLEAR_HALT from a
user process, because the stopped_td variable was overwritten in the
handle_stopped_endpoint() function. So the xhci_endpoint_reset() function will
refuse the reset and communication with device can not run over this endpoint.
https://bugzilla.kernel.org/show_bug.cgi?id=60699

Signed-off-by: Florian Wolter <wolly84@web.de>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This commit is contained in:
Florian Wolter 2013-08-14 10:33:16 +02:00 committed by Sarah Sharp
parent 8b3d45705e
commit 526867c3ca

View file

@ -869,8 +869,12 @@ static void handle_stopped_endpoint(struct xhci_hcd *xhci,
/* Otherwise ring the doorbell(s) to restart queued transfers */
ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
}
ep->stopped_td = NULL;
ep->stopped_trb = NULL;
/* Clear stopped_td and stopped_trb if endpoint is not halted */
if (!(ep->ep_state & EP_HALTED)) {
ep->stopped_td = NULL;
ep->stopped_trb = NULL;
}
/*
* Drop the lock and complete the URBs in the cancelled TD list.