If cdns2_gadget_ep_alloc_request() fails, a null pointer dereference
occurs. Add a check to prevent it.

Fixes: 3eb1f1efe204 ("usb: cdns2: Add main part of Cadence USBHS driver")
Cc: stable@vger.kernel.org
Signed-off-by: Haoxiang Li <lihaoxiang@isrc.iscas.ac.cn>
---
 drivers/usb/gadget/udc/cdns2/cdns2-gadget.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c b/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c
index 9b53daf76583..c5b9dae743d8 100644
--- a/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c
+++ b/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c
@@ -1725,6 +1725,8 @@ static int cdns2_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
 		struct cdns2_request *preq;
 
 		zlp_request = cdns2_gadget_ep_alloc_request(ep, GFP_ATOMIC);
+		if (!zlp_request)
+			return -ENOMEM;
 		zlp_request->buf = pdev->zlp_buf;
 		zlp_request->length = 0;
 
-- 
2.25.1

On Wed, Dec 24, 2025 at 05:38:45PM +0800, Haoxiang Li wrote:
> If cdns2_gadget_ep_alloc_request() fails, a null pointer dereference
> occurs. Add a check to prevent it.
> 
> Fixes: 3eb1f1efe204 ("usb: cdns2: Add main part of Cadence USBHS driver")
> Cc: stable@vger.kernel.org
> Signed-off-by: Haoxiang Li <lihaoxiang@isrc.iscas.ac.cn>
> ---
>  drivers/usb/gadget/udc/cdns2/cdns2-gadget.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c b/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c
> index 9b53daf76583..c5b9dae743d8 100644
> --- a/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c
> +++ b/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c
> @@ -1725,6 +1725,8 @@ static int cdns2_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
>  		struct cdns2_request *preq;
>  
>  		zlp_request = cdns2_gadget_ep_alloc_request(ep, GFP_ATOMIC);
> +		if (!zlp_request)
> +			return -ENOMEM;

As stated before, you need to document the tool that you use to find
these types of things.

And how was this tested?

thanks,

greg k-h