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

[Borislav Petkov]

On Sat, Jul 09, 2022 at 03:41:19PM -0700, H. Peter Anvin wrote:
> In ABI/API terms, that symbol has the semantic of connecting the API version
> to the underlying ABI version; a piece of code that sees an enumeration type
> > SETUP_ENUM_MAX must by definition treat it as an opaque blob. In the
> future, should it become warranted, we may add flags that indicate how
> unaware code should handle them, but I don't think we can engineer that
> right now.

Ok, let's hope it doesn't come to that and userspace behaves... <eyeroll>

So, I'm going to send the below to Linus now so that 5.19 releases fixed
and then queue Jason's patch next week.

Thx.

---

From: Borislav Petkov <bp@xxxxxxx>
Date: Sun, 10 Jul 2022 11:15:47 +0200
Subject: [PATCH] x86/boot: Fix the setup data types max limit

Commit in Fixes forgot to change the SETUP_TYPE_MAX definition which
contains the highest valid setup data type.

Correct that.

Fixes: 5ea98e01ab52 ("x86/boot: Add Confidential Computing type to setup_data")
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lore.kernel.org/r/ddba81dd-cc92-699c-5274-785396a17fb5@xxxxxxxxx
---
 arch/x86/include/uapi/asm/bootparam.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
index bea5cdcdf532..e02a8a8ef23c 100644
--- a/arch/x86/include/uapi/asm/bootparam.h
+++ b/arch/x86/include/uapi/asm/bootparam.h
@@ -15,7 +15,7 @@
 #define SETUP_INDIRECT			(1<<31)
 
 /* SETUP_INDIRECT | max(SETUP_*) */
-#define SETUP_TYPE_MAX			(SETUP_INDIRECT | SETUP_JAILHOUSE)
+#define SETUP_TYPE_MAX			(SETUP_INDIRECT | SETUP_CC_BLOB)
 
 /* ram_size flags */
 #define RAMDISK_IMAGE_START_MASK	0x07FF
-- 
2.35.1


-- 
Regards/Gruss,
    Boris.

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