usb: dwc3: gadget: Avoid continuing preparing TRBs during teardown

Add checks similar to dwc3_gadget_ep_queue() before kicking off
transfers after getting an endpoint completion event.   Since cleaning
up completed requests will momentarily unlock dwc->lock, there is a
chance for a sequence like pullup disable to be executed.  This can
lead to preparing a TRB, which will be removed by the pullup disable
routine.

Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
Link: https://lore.kernel.org/r/1616146285-19149-2-git-send-email-wcheng@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 4834ac1..d366f41 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2917,6 +2917,11 @@ static void dwc3_gadget_ep_cleanup_completed_requests(struct dwc3_ep *dep,
 static bool dwc3_gadget_ep_should_continue(struct dwc3_ep *dep)
 {
        struct dwc3_request     *req;
+       struct dwc3             *dwc = dep->dwc;
+
+       if (!dep->endpoint.desc || !dwc->pullups_connected ||
+           !dwc->connected)
+               return false;
 
        if (!list_empty(&dep->pending_list))
                return true;