Re: [PATCH tip v8] x86/setup: Use rng seeds from setup_data

From: Borislav Petkov
Date: Sat Jul 09 2022 - 06:21:46 EST


On Sat, Jul 09, 2022 at 11:49:29AM +0200, Borislav Petkov wrote:
> On Fri, Jul 08, 2022 at 06:51:16PM -0700, H. Peter Anvin wrote:
> > #define SETUP_ENUM_MAX SETUP_RNG_SEED
> > #define SETUP_INDIRECT (1<<31)
> > #define SETUP_TYPE_MAX (SETUP_ENUM_MAX | SETUP_INDIRECT)
>
> Wait, if we get to add a new number, SETUP_ENUM_MAX and thus
> SETUP_TYPE_MAX will change. And they're uapi too...

Err, we've already dropped the ball there:

#define SETUP_INDIRECT (1<<31)

/* SETUP_INDIRECT | max(SETUP_*) */
#define SETUP_TYPE_MAX (SETUP_INDIRECT | SETUP_JAILHOUSE)

and by "we" I probably mean "me" because I didn't catch that with
SETUP_CC_BLOB.

The good news is, CC_BLOB is not in a released kernel yet so we still
have chance to fix it properly...

;-\

--
Regards/Gruss,
Boris.

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