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Date: Mon, 27 Jan 2014 09:24:17 -0800
Message-ID: <CAGXu5jKXqUhTdhX_n8xSe+d3sPmZ0SK-aTQh2jCXWL6TgA5o=w@mail.gmail.com>
Subject: Re: [GIT PULL] x86/kaslr for v3.14
From: Kees Cook <keescook@chromium.org>
To: Richard Weinberger <richard@nod.at>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>, "H. Peter Anvin" <hpa@zytor.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Cong Ding <dinggnu@gmail.com>, Ingo Molnar <mingo@elte.hu>,
        Ingo Molnar <mingo@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Mathias Krause <minipli@googlemail.com>,
        Michael Davidson <md@google.com>, Thomas Gleixner <tglx@linutronix.de>,
        Wei Yongjun <yongjun_wei@trendmicro.com.cn>
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On Mon, Jan 27, 2014 at 9:20 AM, Richard Weinberger <richard@nod.at> wrote:
> Am 27.01.2014 18:05, schrieb Kees Cook:
>> I would argue that decoding a non-panic oops on a running system is
>> entirely possible as-is, since the offset can be found from
>> /proc/kallsyms as root. It was the dead system that needed the offset
>> exported: via text in the panic, or via an ELF note in a core.
>
> The problem is that you have to pickup information from two sources.
> As a kernel developer users/customers often show you a backtrace (oops or panic)
> and want you do find the problem.
> They barley manage it copy&paste the topmost full trace from dmesg or /var/log/messages.
> If I have to ask them a bit later to tell me the offset from /proc/kallsyms or something else
> I'm lost. Mostly because they have already rebooted the box...

As long as I can turn it off, I'd be happy. :)
/proc/sys/kernel/kaslr_in_oops or something?

-Kees

-- 
Kees Cook
Chrome OS Security
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