From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Florian Wolter , Sarah Sharp , Jonghwan Choi Subject: [ 32/57] xhci: Fix race between ep halt and URB cancellation Date: Wed, 2 Oct 2013 21:08:58 -0700 Message-Id: <20131003040638.800608740@linuxfoundation.org> In-Reply-To: <20131003040636.600441214@linuxfoundation.org> References: <20131003040636.600441214@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.11-stable review patch. If anyone has any objections, please let me know. ------------------ From: Florian Wolter commit 526867c3ca0caa2e3e846cb993b0f961c33c2abb upstream. 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 Signed-off-by: Sarah Sharp Cc: Jonghwan Choi Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-ring.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -857,8 +857,12 @@ remove_finished_td: /* 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.