linux-kernel - Re: [PATCH v2 0/5] x86/fault: #PF improvements, mostly related to USER bit

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: <20181122095233.GM2131@hirez.programming.kicks-ass.net>
Date:   Thu, 22 Nov 2018 10:52:33 +0100
From:   Peter Zijlstra <peterz@...radead.org>
To:     Andy Lutomirski <luto@...nel.org>
Cc:     x86@...nel.org, LKML <linux-kernel@...r.kernel.org>,
        Yu-cheng Yu <yu-cheng.yu@...el.com>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        Borislav Petkov <bp@...en8.de>
Subject: Re: [PATCH v2 0/5] x86/fault: #PF improvements, mostly related to
 USER bit

On Wed, Nov 21, 2018 at 03:11:21PM -0800, Andy Lutomirski wrote:
> This series is a whole bunch of page fault cleanups, plus a couple
> of OOPS diagnostic improvements.  The overall goals are to clean up
> handling of the faulting CPL, the USER bit in the error_code, and
> the log messages generated by #PF OOPSes.
> 
> This series can also be seen as CET preparation.  CET introduces the
> WRUSS instruction, which is the very first way for CPL 0 code to
> cause a #PF fault with the USER bit set.  Let's get the page fault
> code into shape before we start using WRUSS :)
> 
> Changes from v1:
>   - Rebase on top of tip:x86/mm, now that a bunch of v1 was applied.
>     The only material changes are that 'x86/fault: Check
>     user_mode(regs) when validating a stack extension' is gone
>     because the code it fixed has been deleted and that 'x86/fault:
>     Remove sw_error_code' lost the hunk that changed the same code.
> 
> Andy Lutomirski (5):
>   x86/fault: Remove sw_error_code
>   x86/fault: Don't try to recover from an implicit supervisor access
>   x86/oops: Show the correct CS value in show_regs()
>   x86/fault: Decode page fault OOPSes better
>   x86/vsyscall/64: Use X86_PF constants in the simulated #PF error code
> 
>  arch/x86/entry/vsyscall/vsyscall_64.c |   2 +-
>  arch/x86/kernel/process_64.c          |   5 +-
>  arch/x86/mm/fault.c                   | 144 +++++++++++++++++++-------
>  3 files changed, 108 insertions(+), 43 deletions(-)

All looks good to me,

Acked-by: Peter Zijlstra (Intel) <peterz@...radead.org>