Re: [PATCH] usb: cdns2: fix memory double free in cdns2_gadget_giveback

[Greg KH <gregkh@linuxfoundation.org>]

On Fri, Dec 26, 2025 at 11:17:13AM +0800, ReBeating wrote:
> A patch similar to commit 5fd9e45f1ebc("usb: cdns3: fix memory double
>  free when handle zero packet").
> 
> As 5fd9e45f1ebc points out, the cdns2_gadget_giveback() function also has
> the same memory double free issue when handling zero-length packets.
> 
> Add check for usb_gadget_giveback_request() to avoid double free of memory.
> If it's additional zero length packet request, do not call 
> usb_gadget_giveback_request().
> 
> Signed-off-by: ReBeating <rebeating@163.com>
> ---
>  drivers/usb/gadget/udc/cdns2/cdns2-gadget.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c b/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c
> index 7e69944ef18a..4f7898c2e364 100644
> --- a/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c
> +++ b/drivers/usb/gadget/udc/cdns2/cdns2-gadget.c
> @@ -253,7 +253,7 @@ void cdns2_gadget_giveback(struct cdns2_endpoint *pep,
>  
>  	trace_cdns2_request_giveback(preq);
>  
> -	if (request->complete) {
> +	if (request->complete && request->buf != pdev->zlp_buf) {
>  		spin_unlock(&pdev->lock);
>  		usb_gadget_giveback_request(&pep->endpoint, request);
>  		spin_lock(&pdev->lock);
> -- 
> 2.34.1
> 
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
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created.  Hopefully you will not take offence and will fix the problem
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