lkml.org 
[lkml]   [2022]   [Mar]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 16/26] usb: gadget: aspeed: remove usage of list iterator past the loop body
Date
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>
---
drivers/usb/gadget/udc/aspeed-vhub/epn.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/gadget/udc/aspeed-vhub/epn.c b/drivers/usb/gadget/udc/aspeed-vhub/epn.c
index 917892ca8753..b5252880b389 100644
--- a/drivers/usb/gadget/udc/aspeed-vhub/epn.c
+++ b/drivers/usb/gadget/udc/aspeed-vhub/epn.c
@@ -466,19 +466,21 @@ static int ast_vhub_epn_dequeue(struct usb_ep* u_ep, struct usb_request *u_req)
{
struct ast_vhub_ep *ep = to_ast_ep(u_ep);
struct ast_vhub *vhub = ep->vhub;
- struct ast_vhub_req *req;
+ struct ast_vhub_req *req = NULL, *iter;
unsigned long flags;
int rc = -EINVAL;

spin_lock_irqsave(&vhub->lock, flags);

/* Make sure it's actually queued on this endpoint */
- list_for_each_entry (req, &ep->queue, queue) {
- if (&req->req == u_req)
- break;
+ list_for_each_entry(iter, &ep->queue, queue) {
+ if (&iter->req != u_req)
+ continue;
+ req = iter;
+ break;
}

- if (&req->req == u_req) {
+ if (req) {
EPVDBG(ep, "dequeue req @%p active=%d\n",
req, req->active);
if (req->active)
--
2.25.1
\
 
 \ /
  Last update: 2022-03-08 18:22    [W:0.141 / U:0.080 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site