Re: [PATCH v2 13/16] block: sed-opal: check size of shadow mbr

[Scott Bauer]

On Thu, Jan 17, 2019 at 09:31:53PM +0000, David Kozub wrote:
> From: Jonas Rabenstein <jonas.rabenstein@xxxxxxxxxxxxxxxxxxxxxxx>
> 
> Check whether the shadow mbr does fit in the provided space on the
> target. Also a proper firmware should handle this case and return an
> error we may prevent problems or even damage with crappy firmwares.
> +	len = response_get_u64(&dev->parsed, 4);
> +	if (shadow->offset + shadow->size > len) {
> +		pr_debug("MBR: does not fit in shadow (%llu vs. %llu)\n",
> +			 shadow->offset + shadow->size, len);
> +		return -ENOSPC;
> +	}

Can we please change this check to the following:

if (shadow->size > len || shadow->offset > len - shadow->size)

Thanks

> -- 
> 2.20.1
> 
>