Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Mon, 8 May 2017 15:53:20 +0200
From: Daniel Gruss <>
To: David Gens <>,
        Thomas Garnier
CC: kernel list <>,
        Kernel Hardening
        <>, <>,
        Michael Schwarz
        Richard Fellner
        "Kirill A. Shutemov"
        Ingo Molnar <>, <>
Subject: Re: [RFC, PATCH] x86_64: KAISER - do not map
 kernel in user mode

On 06.05.2017 10:38, Daniel Gruss wrote:
> On 2017-05-06 06:02, David Gens wrote:
>> Assuming that their patch indeed leaks per-cpu addresses.. it might not
>> necessarily
>> be required to change it.
> I think we're not leaking them (unless we still have some bug in our code).

Just to correct my answer here as well: Although we experimented with fixed mappings for per-cpu addresses, the current 
patch does not incorporate this yet, so it indeed still leaks. However, it is not a severe problem. The mapping of the 
required (per-cpu) variables would be at a fixed location in the user CR3, instead of the ones that are used in the kernel.

Powered by blists - more mailing lists

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.