[PATCH 10/26] usb: gadget: udc: mv_udc_core: remove usage of list iterator past the loop body
From: Jakob Koschel
Date: Sun Mar 06 2022 - 12:51:44 EST
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@xxxxxxxxx/
Signed-off-by: Jakob Koschel <jakobkoschel@xxxxxxxxx>
---
drivers/usb/gadget/udc/mv_udc_core.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/gadget/udc/mv_udc_core.c b/drivers/usb/gadget/udc/mv_udc_core.c
index b6d34dda028b..67d935d29cb6 100644
--- a/drivers/usb/gadget/udc/mv_udc_core.c
+++ b/drivers/usb/gadget/udc/mv_udc_core.c
@@ -771,7 +771,7 @@ static void mv_prime_ep(struct mv_ep *ep, struct mv_req *req)
static int mv_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
{
struct mv_ep *ep = container_of(_ep, struct mv_ep, ep);
- struct mv_req *req;
+ struct mv_req *req = NULL, *tmp;
struct mv_udc *udc = ep->udc;
unsigned long flags;
int stopped, ret = 0;
@@ -793,11 +793,13 @@ static int mv_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
writel(epctrlx, &udc->op_regs->epctrlx[ep->ep_num]);
/* 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(tmp, &ep->queue, queue) {
+ if (&tmp->req == _req) {
+ req = tmp;
break;
+ }
}
- if (&req->req != _req) {
+ if (!req) {
ret = -EINVAL;
goto out;
}
--
2.25.1