[PATCH] usb: dwc3: gadget: Fail request submission if it was already queued

From: Manu Gautam
Date: Fri Jan 11 2019 - 01:02:27 EST


If a function driver tries to re-submit an already queued request,
it can results in corruption of pending/started request lists.
Catch such conditions and fail the request submission to DCD.

Signed-off-by: Manu Gautam <mgautam@xxxxxxxxxxxxxx>
---
drivers/usb/dwc3/gadget.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 679c12e14522..51716c6b286a 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1290,6 +1290,12 @@ static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
&req->request, req->dep->name))
return -EINVAL;

+ if (req->request.status == -EINPROGRESS) {
+ dev_err(dwc->dev, "%s: %pK request already in queue\n",
+ dep->name, req);
+ return -EBUSY;
+ }
+
pm_runtime_get(dwc->dev);

req->request.actual = 0;
--
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