Commit 42f2890a authored by Mathias Nyman's avatar Mathias Nyman Committed by Greg Kroah-Hartman
Browse files

xhci: add xhci_virt_ep_to_ring() helper 



Two existing ring helpers, xhci_triad_to_transfer_ring() and
xhci_stream_id_to_ring() have partially similar functionality.
Both have some limitation, especieally with boundary checking.

Add a new xhci_virt_ep_to_ring() helper with proper boundary checking
that can replace parts of one helper, and later will completely
replace the other helper.

Signed-off-by: default avatarMathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210129130044.206855-8-mathias.nyman@linux.intel.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 03ed579d

drivers/usb/host/xhci-ring.c

+22 −24
Original line number Diff line number Diff line
@@ -466,6 +466,26 @@ static struct xhci_virt_ep *xhci_get_virt_ep(struct xhci_hcd *xhci, 
	return &xhci->devs[slot_id]->eps[ep_index];

}



static struct xhci_ring *xhci_virt_ep_to_ring(struct xhci_hcd *xhci,

					      struct xhci_virt_ep *ep,

					      unsigned int stream_id)

{

	/* common case, no streams */

	if (!(ep->ep_state & EP_HAS_STREAMS))

		return ep->ring;



	if (!ep->stream_info)

		return NULL;



	if (stream_id == 0 || stream_id >= ep->stream_info->num_streams) {

		xhci_warn(xhci, "Invalid stream_id %u request for slot_id %u ep_index %u\n",

			  stream_id, ep->vdev->slot_id, ep->ep_index);

		return NULL;

	}



	return ep->stream_info->stream_rings[stream_id];

}



/* Get the right ring for the given slot_id, ep_index and stream_id.

 * If the endpoint supports streams, boundary check the URB's stream ID.

 * If the endpoint doesn't support streams, return the singular endpoint ring.
@@ -480,29 +500,7 @@ struct xhci_ring *xhci_triad_to_transfer_ring(struct xhci_hcd *xhci, 
	if (!ep)

		return NULL;



	/* Common case: no streams */

	if (!(ep->ep_state & EP_HAS_STREAMS))

		return ep->ring;



	if (stream_id == 0) {

		xhci_warn(xhci,

				"WARN: Slot ID %u, ep index %u has streams, "

				"but URB has no stream ID.\n",

				slot_id, ep_index);

		return NULL;

	}



	if (stream_id < ep->stream_info->num_streams)

		return ep->stream_info->stream_rings[stream_id];



	xhci_warn(xhci,

			"WARN: Slot ID %u, ep index %u has "

			"stream IDs 1 to %u allocated, "

			"but stream ID %u is requested.\n",

			slot_id, ep_index,

			ep->stream_info->num_streams - 1,

			stream_id);

	return NULL;

	return xhci_virt_ep_to_ring(xhci, ep, stream_id);

}
@@ -1100,7 +1098,7 @@ static void xhci_handle_cmd_set_deq(struct xhci_hcd *xhci, int slot_id, 
	if (!ep)

		return;



	ep_ring = xhci_stream_id_to_ring(ep->vdev, ep_index, stream_id);

	ep_ring = xhci_virt_ep_to_ring(xhci, ep, stream_id);

	if (!ep_ring) {

		xhci_warn(xhci, "WARN Set TR deq ptr command for freed stream ID %u\n",

				stream_id);