Re: [PATCH] usb: storage: isd200: fix error checks in isd200_{read,write}_config()

[Alan Stern]

On Thu, Mar 14, 2024 at 12:31:36PM +0300, Roman Smirnov wrote:
> The expression result >= 0 will be true even if usb_stor_ctrl_transfer()
> returns an error code. It is necessary to compare result with
> USB_STOR_XFER_GOOD.
> 
> Found by Linux Verification Center (linuxtesting.org) with Svace.
> 
> Signed-off-by: Roman Smirnov <r.smirnov@xxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Reviewed-by: Sergey Shtylyov <s.shtylyov@xxxxxx>
> ---

Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>

>  drivers/usb/storage/isd200.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/storage/isd200.c b/drivers/usb/storage/isd200.c
> index 300aeef160e7..2a1531793820 100644
> --- a/drivers/usb/storage/isd200.c
> +++ b/drivers/usb/storage/isd200.c
> @@ -774,7 +774,7 @@ static int isd200_write_config( struct us_data *us )
>  		(void *) &info->ConfigData, 
>  		sizeof(info->ConfigData));
>  
> -	if (result >= 0) {
> +	if (result == USB_STOR_XFER_GOOD) {
>  		usb_stor_dbg(us, "   ISD200 Config Data was written successfully\n");
>  	} else {
>  		usb_stor_dbg(us, "   Request to write ISD200 Config Data failed!\n");
> @@ -816,7 +816,7 @@ static int isd200_read_config( struct us_data *us )
>  		sizeof(info->ConfigData));
>  
>  
> -	if (result >= 0) {
> +	if (result == USB_STOR_XFER_GOOD) {
>  		usb_stor_dbg(us, "   Retrieved the following ISD200 Config Data:\n");
>  #ifdef CONFIG_USB_STORAGE_DEBUG
>  		isd200_log_config(us, info);
> -- 
> 2.34.1
> 
>