Commit 72149b81 authored Mar 08, 2022 by Jakob Koschel Committed by Greg Kroah-Hartman Mar 15, 2022

usb: gadget: udc: gr_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: Jakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220308171818.384491-8-jakobkoschel@gmail.com

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 7336cccf

drivers/usb/gadget/udc/gr_udc.c

+7 −5

Original line number	Diff line number	Diff line
		@@ -1690,7 +1690,7 @@ static int gr_queue_ext(struct usb_ep _ep, struct usb_request _req,
		/* Dequeue JUST ONE request */
		static int gr_dequeue(struct usb_ep _ep, struct usb_request _req)
		{
		struct gr_request *req;
		struct gr_request req = NULL, iter;
		struct gr_ep *ep;
		struct gr_udc *dev;
		int ret = 0;
		@@ -1710,11 +1710,13 @@ static int gr_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) {
		ret = -EINVAL;
		goto out;
		}