The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 05645366f3893c160bd39ca49f3fe2f2f026f58b Mon Sep 17 00:00:00 2001
From: Mayank Rana mrana@codeaurora.org Date: Fri, 23 Mar 2018 10:05:33 -0700 Subject: [PATCH] usb: dwc3: gadget: Fix list_del corruption in dwc3_ep_dequeue
dwc3_ep_dequeue() waits for completion of End Transfer command using wait_event_lock_irq(), which will release the dwc3->lock while waiting and reacquire after completion. This allows a potential race condition with ep_disable() which also removes all requests from started_list and pending_list.
The check for NULL r->trb should catch this but currently it exits to the wrong 'out1' label which calls dwc3_gadget_giveback(). Since its list entry was already removed, if CONFIG_DEBUG_LIST is enabled a 'list_del corruption' bug is thrown since its next/prev pointers are already LIST_POISON1/2. If r->trb is NULL it should simply exit to 'out0'.
Fixes: cf3113d893d4 ("usb: dwc3: gadget: properly increment dequeue pointer on ep_dequeue") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Mayank Rana mrana@codeaurora.org Signed-off-by: Jack Pham jackp@codeaurora.org Signed-off-by: Felipe Balbi felipe.balbi@linux.intel.com
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index eeb30133878e..69bf137aab37 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1395,7 +1395,7 @@ static int dwc3_gadget_ep_dequeue(struct usb_ep *ep, dwc->lock);
if (!r->trb) - goto out1; + goto out0;
if (r->num_pending_sgs) { struct dwc3_trb *trb;