Commit 7336cccf authored by Jakob Koschel's avatar Jakob Koschel Committed by Greg Kroah-Hartman
Browse files

usb: gadget: goku_udc: remove usage of list iterator past the loop body 

If the list representing the request queue does not contain the expected
request, the value of the list_for_each_entry() iterator will not point
to a valid structure. To avoid type confusion in such case, the list
iterator scope will be limited to the list_for_each_entry() loop.

In preparation to limiting scope of the list iterator to the list traversal
loop, use a dedicated pointer to point to the found request object [1].

Link: https://lore.kernel.org/all/YhdfEIwI4EdtHdym@kroah.com/


Signed-off-by: default avatarJakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220308171818.384491-7-jakobkoschel@gmail.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 2390ea9c

drivers/usb/gadget/udc/goku_udc.c

+7 −5
Original line number Diff line number Diff line
@@ -809,7 +809,7 @@ static void nuke(struct goku_ep *ep, int status) 
/* dequeue JUST ONE request */

static int goku_dequeue(struct usb_ep *_ep, struct usb_request *_req)

{

	struct goku_request	*req;

	struct goku_request	*req = NULL, *iter;

	struct goku_ep		*ep;

	struct goku_udc		*dev;

	unsigned long		flags;
@@ -833,11 +833,13 @@ static int goku_dequeue(struct usb_ep *_ep, struct usb_request *_req) 
	spin_lock_irqsave(&dev->lock, flags);



	/* make sure it's actually queued on this endpoint */

	list_for_each_entry (req, &ep->queue, queue) {

		if (&req->req == _req)

	list_for_each_entry(iter, &ep->queue, queue) {

		if (&iter->req != _req)

			continue;

		req = iter;

		break;

	}

	if (&req->req != _req) {

	if (!req) {

		spin_unlock_irqrestore (&dev->lock, flags);

		return -EINVAL;

	}