linux-kernel - Re: [PATCHv2 2/5] x86/mm: introduce mmap_{,legacy}

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: <CALCETrUHLpsrB0M3rkrxw8R=6Dto5gFz+enP=W3C6WPDTa36GA@mail.gmail.com>
Date:   Tue, 17 Jan 2017 12:27:00 -0800
From:   Andy Lutomirski <luto@...capital.net>
To:     Dmitry Safonov <dsafonov@...tuozzo.com>
Cc:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Dmitry Safonov <0x7f454c46@...il.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H. Peter Anvin" <hpa@...or.com>,
        Andy Lutomirski <luto@...nel.org>,
        Borislav Petkov <bp@...e.de>, X86 ML <x86@...nel.org>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>
Subject: Re: [PATCHv2 2/5] x86/mm: introduce mmap_{,legacy}_base

On Mon, Jan 16, 2017 at 4:33 AM, Dmitry Safonov <dsafonov@...tuozzo.com> wrote:
> In the following patch they will be used to compute:
> - mmap_base in compat sys_mmap() in native 64-bit binary
> and vice-versa
> - mmap_base for native sys_mmap() in compat x32/ia32-bit binary.

I may be wrong here, but I suspect that you're repeating something
that I consider to be a mistake that's all over the x86 code.
Specifically, you're distinguishing "native" from "compat" instead of
"32-bit" from "64-bit".  If you did the latter, then you wouldn't need
the "native" case to work differently on 32-bit kernels vs 64-bit
kernels, I think.  Would making this change make your code simpler?

The x86 signal code is the worst offender IMO.

--Andy