[PATCH 5.0 087/122] usb: dwc3: Reset num_trbs after skipping

[Greg Kroah-Hartman]

From: Thinh Nguyen <thinh.nguyen@xxxxxxxxxxxx>

commit c7152763f02e05567da27462b2277a554e507c89 upstream.

Currently req->num_trbs is not reset after the TRBs are skipped and
processed from the cancelled list. The gadget driver may reuse the
request with an invalid req->num_trbs, and DWC3 will incorrectly skip
trbs. To fix this, simply reset req->num_trbs to 0 after skipping
through all of them.

Fixes: c3acd5901414 ("usb: dwc3: gadget: use num_trbs when skipping TRBs on ->dequeue()")
Signed-off-by: Thinh Nguyen <thinhn@xxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/dwc3/gadget.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1506,6 +1506,8 @@ static void dwc3_gadget_ep_skip_trbs(str
 		trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
 		dwc3_ep_inc_deq(dep);
 	}
+
+	req->num_trbs = 0;
 }
 
 static void dwc3_gadget_ep_cleanup_cancelled_requests(struct dwc3_ep *dep)