Re: [PATCH] USB: host: Check for null res pointer

[Greg KH]

On Mon, Dec 20, 2021 at 02:49:46PM +0800, Jiasheng Jiang wrote:
> The return value of platform_get_resource() needs to be checked.
> To avoid use of error pointer in case of the failure of alloc.
> 
> Fixes: 4808a1c02611 ("[PATCH] USB: Add isp116x-hcd USB host controller driver")
> Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
> ---
>  drivers/usb/host/isp116x-hcd.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/usb/host/isp116x-hcd.c b/drivers/usb/host/isp116x-hcd.c
> index 8835f6bd528e..addd2b43a14c 100644
> --- a/drivers/usb/host/isp116x-hcd.c
> +++ b/drivers/usb/host/isp116x-hcd.c
> @@ -1541,9 +1541,15 @@ static int isp116x_remove(struct platform_device *pdev)
>  
>  	iounmap(isp116x->data_reg);
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +	if (!res)
> +		return -EINVAL;

You really can not fail a remove call.  If you do so here, memory will
leak.

Please make this work no matter what.

thanks,

greg k-h