Re: [PATCH v14 2/3] virt: Add TDX guest driver

[Borislav Petkov]

On Wed, Sep 28, 2022 at 02:55:34PM -0700, Kuppuswamy Sathyanarayanan wrote:
> +static long tdx_get_report(void __user *argp)
> +{
> +	u8 *reportdata, *tdreport;
> +	struct tdx_report_req req;
> +	long ret;
> +
> +	if (copy_from_user(&req, argp, sizeof(req)))
> +		return -EFAULT;
> +
> +	/*
> +	 * Per TDX Module 1.0 specification, section titled
> +	 * "TDG.MR.REPORT", REPORTDATA length is fixed as
> +	 * TDX_REPORTDATA_LEN, TDREPORT length is fixed as
> +	 * TDX_REPORT_LEN, and TDREPORT subtype is fixed as 0.
> +	 */
> +	if (req.subtype || req.rpd_len != TDX_REPORTDATA_LEN ||
> +	    req.tdr_len != TDX_REPORT_LEN)
> +		return -EINVAL;
> +
> +	if (memchr_inv(req.reserved, 0, sizeof(req.reserved)))

I'm guessing we should issue something here to userspace to let it know
why the it fails getting the report.

Otherwise it is starting to look good and boring. :)

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette