linux-kernel - Re: [PATCH v2 1/8] x86/vsyscall: Remove the vsyscall=native documentation

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: <201906271026.6AB1D9493@keescook>
Date:   Thu, 27 Jun 2019 10:26:11 -0700
From:   Kees Cook <keescook@...omium.org>
To:     Andy Lutomirski <luto@...nel.org>
Cc:     x86@...nel.org, LKML <linux-kernel@...r.kernel.org>,
        Florian Weimer <fweimer@...hat.com>,
        Jann Horn <jannh@...gle.com>, stable@...r.kernel.org,
        Borislav Petkov <bp@...en8.de>,
        Kernel Hardening <kernel-hardening@...ts.openwall.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH v2 1/8] x86/vsyscall: Remove the vsyscall=native
 documentation

On Wed, Jun 26, 2019 at 09:45:02PM -0700, Andy Lutomirski wrote:
> The vsyscall=native feature is gone -- remove the docs.
> 
> Fixes: 076ca272a14c ("x86/vsyscall/64: Drop "native" vsyscalls")
> Cc: stable@...r.kernel.org
> Cc: Kees Cook <keescook@...omium.org>
> Cc: Borislav Petkov <bp@...en8.de>
> Cc: Kernel Hardening <kernel-hardening@...ts.openwall.com>
> Cc: Peter Zijlstra <peterz@...radead.org>
> Cc: Thomas Gleixner <tglx@...utronix.de>
> Signed-off-by: Andy Lutomirski <luto@...nel.org>

Acked-by: Kees Cook <keescook@...omium.org>

-Kees

> ---
>  Documentation/admin-guide/kernel-parameters.txt | 6 ------
>  1 file changed, 6 deletions(-)
> 
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index 138f6664b2e2..0082d1e56999 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -5102,12 +5102,6 @@
>  			emulate     [default] Vsyscalls turn into traps and are
>  			            emulated reasonably safely.
>  
> -			native      Vsyscalls are native syscall instructions.
> -			            This is a little bit faster than trapping
> -			            and makes a few dynamic recompilers work
> -			            better than they would in emulation mode.
> -			            It also makes exploits much easier to write.
> -
>  			none        Vsyscalls don't work at all.  This makes
>  			            them quite hard to use for exploits but
>  			            might break your system.
> -- 
> 2.21.0
> 

-- 
Kees Cook