Date:   Tue, 7 Dec 2021 15:40:37 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Guo Zhengkui <guozhengkui@vivo.com>
Cc:     Alan Stern <stern@rowland.harvard.edu>, Li Jun <jun.li@nxp.com>,
        Kishon Vijay Abraham I <kishon@ti.com>,
        Andrey Konovalov <andreyknvl@gmail.com>,
        Peter Chen <peter.chen@nxp.com>,
        "open list:USB SUBSYSTEM" <linux-usb@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>, kernel@vivo.com
Subject: Re: [PATCH] usb: core: hcd: fix bug: application of sizeof to pointer
Message-ID: <Ya9yZX3JsuO8OcVJ@kroah.com>
References: <20211207135401.5507-1-guozhengkui@vivo.com>
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In-Reply-To: <20211207135401.5507-1-guozhengkui@vivo.com>
Precedence: bulk

On Tue, Dec 07, 2021 at 09:53:47PM +0800, Guo Zhengkui wrote:
> Fix following error:
> ./drivers/usb/core/hcd.c:1284:38-44: ERROR:
> application of sizeof to pointer.

What generated this error?

> 
> Use sizeof(*vaddr) instead.
> 
> Signed-off-by: Guo Zhengkui <guozhengkui@vivo.com>
> ---
>  drivers/usb/core/hcd.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
> index 4d326ee12c36..996d5273cf60 100644
> --- a/drivers/usb/core/hcd.c
> +++ b/drivers/usb/core/hcd.c
> @@ -1281,7 +1281,7 @@ static int hcd_alloc_coherent(struct usb_bus *bus,
>  		return -EFAULT;
>  	}
>  
> -	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
> +	vaddr = hcd_buffer_alloc(bus, size + sizeof(*vaddr),

I think you just broke the code.

Look at this closer and see what the function is doing with this buffer
and if you still think your patch is correct, please rewrite the
changelog text to explain why it is so (hint, just using the output of
coccinelle isn't ok.)

thanks,

greg k-h