[PATCH RESEND] usb: dwc2: gadget: Move a variable assignment behind condition checks in dwc2_hsotg_handle_outdone()

[Markus Elfring]

From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Wed, 19 Apr 2023 20:06:25 +0200

The address of a data structure member was determined before
a corresponding null pointer check in the implementation of
the function “dwc2_hsotg_handle_outdone”.

Thus avoid the risk for undefined behaviour by moving the assignment
for the variable “req” behind some condition checks.

This issue was detected by using the Coccinelle software.

Fixes: 5b7d70c6dbf2 ("USB: Gadget driver for Samsung HS/OtG block")
Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
---
 drivers/usb/dwc2/gadget.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 8b15742d9e8a..cab04816dd6c 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -2389,7 +2389,7 @@ static void dwc2_hsotg_handle_outdone(struct dwc2_hsotg *hsotg, int epnum)
 	u32 epsize = dwc2_readl(hsotg, DOEPTSIZ(epnum));
 	struct dwc2_hsotg_ep *hs_ep = hsotg->eps_out[epnum];
 	struct dwc2_hsotg_req *hs_req = hs_ep->req;
-	struct usb_request *req = &hs_req->req;
+	struct usb_request *req;
 	unsigned int size_left = DXEPTSIZ_XFERSIZE_GET(epsize);
 	int result = 0;

@@ -2408,6 +2408,8 @@ static void dwc2_hsotg_handle_outdone(struct dwc2_hsotg *hsotg, int epnum)
 	if (using_desc_dma(hsotg))
 		size_left = dwc2_gadget_get_xfersize_ddma(hs_ep);

+	req = &hs_req->req;
+
 	if (using_dma(hsotg)) {
 		unsigned int size_done;

--
2.40.0