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usb: gadget: lpc32xx_udc: remove usage of list iterator past the loop body

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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/20220308171818.384491-9-jakobkoschel@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jakob Koschel 2022-03-08 18:18:00 +01:00 committed by Greg Kroah-Hartman
parent 72149b816b
commit 4a2a73bf33
1 changed files with 7 additions and 5 deletions
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12
drivers/usb/gadget/udc/lpc32xx_udc.c
View file

@ -1830,7 +1830,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
static int lpc32xx_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
{
struct lpc32xx_ep *ep;
struct lpc32xx_request *req;
struct lpc32xx_request *req = NULL, *iter;
unsigned long flags;
ep = container_of(_ep, struct lpc32xx_ep, ep);
@ -1840,11 +1840,13 @@ static int lpc32xx_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
spin_lock_irqsave(&ep->udc->lock, flags);
/* make sure it's actually queued on this endpoint */
list_for_each_entry(req, &ep->queue, queue) {
if (&req->req == _req)
break;
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(&ep->udc->lock, flags);
return -EINVAL;
}