linux-kernel - Re: [PATCH 0/3] x86/umip: Fix UMIP insn decoder false positives

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <aM1pNN_ById_l6xR@google.com>
Date: Fri, 19 Sep 2025 07:31:16 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>, 
	Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org, linux-kernel@...r.kernel.org, 
	Dan Snyder <dansnyder@...gle.com>
Subject: Re: [PATCH 0/3] x86/umip: Fix UMIP insn decoder false positives

On Fri, Aug 08, 2025, Sean Christopherson wrote:
> Fix two false positives scenarios where the UMIP #GP logic will incorrectly
> trigger emulation, e.g. due to a partially decoded instruction, or on
> instructions like VMLAUNCH that usurp the register form of '0f 01'.
> 
> Tested with the hack-a-test patch at the end, but I haven't done any testing
> using a real userspace (neither positive nor negative testing).
> 
> Sean Christopherson (3):
>   x86/umip: Check that the instruction opcode is at least two bytes
>   x86/umip: Fix decoding of register forms of 0F 01 (SGDT and SIDT
>     aliases)

Ping on these two, looks like they slipped through the cracks.  FWIW, I wouldn't
consider these urgent enough to squeeze into 6.17, but it'd be nice to get them
into 6.18.