From: "Mihai Donțu" <mihai.dontu@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: Re: my first post
Date: Wed, 17 Jul 2013 13:05:39 +0300 [thread overview]
Message-ID: <20130717130539.557c4f62@mdontu-l> (raw)
In-Reply-To: <000d01ce82b4$2d9c1150$88d433f0$@com>
On Wed, 17 Jul 2013 14:09:20 +0800 merrysoft@tom.com wrote:
> I have meeted a problem with linux kernel 2.6.X.X that my user app
> wants to get thread kernel stack frame ponter(FP) from user space by
> system call or /proc system or any other ways except driver. I do not
> want to write a driver,) to finish it. I have endured this problem
> for a long time.
>
> would anyone please to give me a hint to solve the problem.
>
(I'm ignoring the questionable practicality of this)
People have gone to great lengths not to reveal sensitive addresses
from ring 0, %rsp/%rbp being subject to this restriction. If you
configure your kernel to expose full /dev/mem (CONFIG_STRICT_DEVMEM=n),
then using the image for your running kernel and with a bit of DWARF
knowledge, I _think_ it's possible to list the current running threads
and their contexts (ie. CPU registers). Otherwise, I don't believe
there's any way you can achieve this, other than exploiting a bug. :-)
--
Mihai Donțu
prev parent reply other threads:[~2013-07-17 10:05 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-17 6:09 my first post bob
2013-07-17 10:05 ` Mihai Donțu [this message]
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