iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

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

Browse Source 
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/20220308171818.384491-2-jakobkoschel@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jakob Koschel 2022-03-08 18:17:53 +01:00 committed by Greg Kroah-Hartman
parent ecb0a2f1e9
commit 838884110f
2 changed files with 16 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
drivers/usb/gadget/udc/fsl_qe_udc.c
View File

@ -1776,7 +1776,8 @@ static int qe_ep_queue(struct usb_ep *_ep, struct usb_request *_req,
static int qe_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
{
struct qe_ep *ep = container_of(_ep, struct qe_ep, ep);
struct qe_req *req;
struct qe_req *req = NULL;
struct qe_req *iter;
unsigned long flags;
if (!_ep || !_req)
@ -1785,12 +1786,14 @@ static int qe_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;
}

13
drivers/usb/gadget/udc/fsl_udc_core.c
View File

@ -918,7 +918,8 @@ fsl_ep_queue(struct usb_ep *_ep, struct usb_request *_req, gfp_t gfp_flags)
static int fsl_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
{
struct fsl_ep *ep = container_of(_ep, struct fsl_ep, ep);
struct fsl_req *req;
struct fsl_req *req = NULL;
struct fsl_req *iter;
unsigned long flags;
int ep_num, stopped, ret = 0;
u32 epctrl;
@ -940,11 +941,13 @@ static int fsl_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
fsl_writel(epctrl, &dr_regs->endptctrl[ep_num]);
/* 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) {
ret = -EINVAL;
goto out;
}