From 838884110f0d69136248d290a51c3b1d4882e092 Mon Sep 17 00:00:00 2001 From: Jakob Koschel Date: Tue, 8 Mar 2022 18:17:53 +0100 Subject: [PATCH] usb: gadget: fsl: 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 Link: https://lore.kernel.org/r/20220308171818.384491-2-jakobkoschel@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/udc/fsl_qe_udc.c | 13 ++++++++----- drivers/usb/gadget/udc/fsl_udc_core.c | 13 ++++++++----- 2 files changed, 16 insertions(+), 10 deletions(-) diff --git a/drivers/usb/gadget/udc/fsl_qe_udc.c b/drivers/usb/gadget/udc/fsl_qe_udc.c index 15db7a3..d80a7fe 100644 --- a/drivers/usb/gadget/udc/fsl_qe_udc.c +++ b/drivers/usb/gadget/udc/fsl_qe_udc.c @@ -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; } diff --git a/drivers/usb/gadget/udc/fsl_udc_core.c b/drivers/usb/gadget/udc/fsl_udc_core.c index 29fcb9b..50435e8 100644 --- a/drivers/usb/gadget/udc/fsl_udc_core.c +++ b/drivers/usb/gadget/udc/fsl_udc_core.c @@ -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; } -- 2.7.4