usb: dwc3: ep0: introduce ep0_expect_in flag
This flag will tell us which direction we're
expecting on the next (data or status) phase.
It will help us catching errors of host going
crazy and requesting data of the wrong direction.
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 92673fd..07d2018 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -529,6 +529,7 @@
* @three_stage_setup: set if we perform a three phase setup
* @ep0_status_pending: ep0 status response without a req is pending
* @ep0_bounced: true when we used bounce buffer
+ * @ep0_expect_in: true when we expect a DATA IN transfer
* @ep0_next_event: hold the next expected event
* @ep0state: state of endpoint zero
* @link_state: link state
@@ -575,6 +576,7 @@
unsigned three_stage_setup:1;
unsigned ep0_status_pending:1;
unsigned ep0_bounced:1;
+ unsigned ep0_expect_in:1;
enum dwc3_ep0_next ep0_next_event;
enum dwc3_ep0_state ep0state;
diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 4cc72fd..b66d969 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -545,6 +545,8 @@
dwc->ep0_next_event = DWC3_EP0_NRDY_DATA;
}
+ dwc->ep0_expect_in = !!(ctrl->bRequestType & USB_DIR_IN);
+
if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
ret = dwc3_ep0_std_request(dwc, ctrl);
else
@@ -758,6 +760,20 @@
return;
}
+ /*
+ * One of the possible error cases is when Host _does_
+ * request for Data Phase, but it does so on the wrong
+ * direction.
+ *
+ * Here, we already know ep0_next_event is DATA (see above),
+ * so we only need to check for direction.
+ */
+ if (dwc->ep0_expect_in != event->endpoint_number) {
+ dev_vdbg(dwc->dev, "Wrong direction for Data phase\n");
+ dwc3_ep0_stall_and_restart(dwc);
+ return;
+ }
+
dwc3_ep0_do_control_data(dwc, event);
break;