linux-kernel - Re: Linux 4.15-rc7

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: <CA+55aFyDtWAOaXZuNtCFb=a1MAazxcZ02ut-RkOqGj4mcXyNYA@mail.gmail.com>
Date:   Fri, 12 Jan 2018 11:44:48 -0800
From:   Linus Torvalds <torvalds@...ux-foundation.org>
To:     Pavel Machek <pavel@....cz>
Cc:     Arnd Bergmann <arnd@...db.de>,
        Olivier Galibert <galibert@...ox.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        jikos@...e.cz
Subject: Re: Linux 4.15-rc7

On Fri, Jan 12, 2018 at 11:38 AM, Pavel Machek <pavel@....cz> wrote:
>
> I'll try to do the right thing. OTOH... I don't like the fact that
> kernel memory on my machine is currently readable, probably even from
> javascript.

Oh, absolutely. I'm just saying that it's probably best to try to
start from the x86-64 KPTI model, and see how that works for x86-32.

Maybe some of the 4G:4G entry code could come in handy as a "these are
the issues" kind of thing.

> I tried disabling CPU caches. Just like that, off, boom. My system
> will not survive that, and it looks like 100x slowdown.

Yeah, no. That is not a realistic thing to do on any hardware since
the PPro, I'm afraid.

           Linus