[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <524BAF92.1090705@zytor.com>
Date: Tue, 01 Oct 2013 22:30:58 -0700
From: "H. Peter Anvin" <hpa@...or.com>
To: Ingo Molnar <mingo@...nel.org>
CC: Kees Cook <keescook@...omium.org>, linux-kernel@...r.kernel.org,
x86@...nel.org, kernel-hardening@...ts.openwall.com,
adurbin@...gle.com, Eric Northup <digitaleric@...gle.com>,
jln@...gle.com, wad@...gle.com,
Mathias Krause <minipli@...glemail.com>,
Zhang Yanfei <zhangyanfei@...fujitsu.com>,
Linus Torvalds <torvalds@...ux-foundation.org>,
Andrew Morton <akpm@...ux-foundation.org>,
Arnaldo Carvalho de Melo <acme@...radead.org>,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH v6 0/7] Kernel base address randomization
On 10/01/2013 10:25 PM, Ingo Molnar wrote:
>
> I mean, for example in an oops message we print data in words: the RIP,
> other registers and stack contents. If any of these values lies within the
> randomization range then we could de-randomize it.
>
> So instead of exposing randomized values, we could expose de-randomized
> values.
>
> ( This isn't fool-proof: if some data value happens to lie within the
> random range spuriously then we'll incorrectly transform it. In the
> context of oops messages this should not be a big practical problem
> though. )
>
I don't agree that this isn't a big practical problem. I often find it
necessary to pick out "things that look like pointers". Overall,
derandomization would make it possible to get really confused when you
have things like half a pointer overwritten.
-hpa
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.
