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From: Vasiliy Kulikov <segoon@openwall.com>
To: kernel-hardening@lists.openwall.com
Subject: Re: [kernel-hardening] base address for shared libs
Date: Sat, 30 Jul 2011 22:43:29 +0400	[thread overview]
Message-ID: <20110730184329.GA4447@albatros> (raw)
In-Reply-To: <20110730183830.GA4314@albatros>

Solar,

On Sat, Jul 30, 2011 at 22:38 +0400, Vasiliy Kulikov wrote:
> This is a patch, which should solve the problem.  Note that the default
> base address allocation policy for the mainline is top-down, so
> 0x00110000 was not considered even in x86-32.  Now it should work for
> both 32-bit systems and 32-bit tasks in 64-bit systems.

One note: if watch for ldd output, approx. every 20th output shows that
some library gets 0xffAABBCC address.  If watch for the real task's maps
(via /proc/pid/maps), all libs are located before 0x01AABBCC.

I don't know for sure how ldd allocated memory, but I suspect it wastes
too much 0x00AABBCC addresses, so sometimes there is no place for them.

So, I don't think it is an issue.

Thanks,

-- 
Vasiliy Kulikov
http://www.openwall.com - bringing security into open computing environments

      reply	other threads:[~2011-07-30 18:43 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-07-23 16:22 [kernel-hardening] base address for shared libs Solar Designer
2011-07-24  8:51 ` Vasiliy Kulikov
2011-07-24 14:27   ` Solar Designer
2011-07-24 18:18     ` Vasiliy Kulikov
2011-07-25 19:20     ` Vasiliy Kulikov
2011-08-11  8:32       ` Vasiliy Kulikov
2011-08-12  3:57         ` Solar Designer
2011-08-12  4:21           ` Solar Designer
2011-08-12  8:20             ` Vasiliy Kulikov
2011-08-12  9:20               ` Solar Designer
2011-08-12  9:52                 ` Vasiliy Kulikov
2011-08-12 10:04                   ` Solar Designer
2011-08-12 10:06                     ` Vasiliy Kulikov
2011-07-29  9:27 ` Vasiliy Kulikov
2011-07-30 18:38 ` Vasiliy Kulikov
2011-07-30 18:43   ` Vasiliy Kulikov [this message]

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