Re: [PATCH] USB: legousbtower: fix a signedness bug in tower_probe()

[Johan Hovold <johan@kernel.org>]

On Fri, Oct 11, 2019 at 04:35:25PM +0300, Dan Carpenter wrote:
> The problem is that sizeof() is unsigned long so negative error codes
> are type promoted to high positive values and the condition becomes
> false.
> 
> Fixes: 1d427be4a39d ("USB: legousbtower: fix slab info leak at probe")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
>  drivers/usb/misc/legousbtower.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/misc/legousbtower.c b/drivers/usb/misc/legousbtower.c
> index 9d4c52a7ebe0..835908fe1e65 100644
> --- a/drivers/usb/misc/legousbtower.c
> +++ b/drivers/usb/misc/legousbtower.c
> @@ -881,7 +881,7 @@ static int tower_probe (struct usb_interface *interface, const struct usb_device
>  				  get_version_reply,
>  				  sizeof(*get_version_reply),
>  				  1000);
> -	if (result < sizeof(*get_version_reply)) {
> +	if (result < 0 || result < sizeof(*get_version_reply)) {
>  		if (result >= 0)
>  			result = -EIO;
>  		dev_err(idev, "get version request failed: %d\n", result);

Bah, I should have noticed.

Thanks for fixing this!

Acked-by: Johan Hovold <johan@kernel.org>

Johan