/proc/sys/vm/mmap_min_addr missing

[Valery Reznic]

Hi, Baruh.

I use pre-build kernel from here:
http://ftp.linux.org.uk/pub/linux/arm/fedora/qemu/zImage-versatile-2.6.24-rc7.armv5tel

It's config file 

http://ftp.linux.org.uk/pub/linux/arm/fedora/qemu/config-versatile-2.6.24-rc7

And indeed it has no CONFIG_SECURITY set.

Very strange.. Am  imagined seeing this file here?
Or may be exist another  explanation?

Valery.



----- Original Message -----
> From: Baruch Siach <baruch at tkos.co.il>
> To: Valery Reznic <valery_reznic at yahoo.com>
> Cc: shimi <linux-il at shimi.net>; linux-il <linux-il at cs.huji.ac.il>
> Sent: Tuesday, January 15, 2013 1:36 PM
> Subject: Re: /proc/sys/vm/mmap_min_addr missing
> 
> Hi Valery,
> 
> On Tue, Jan 15, 2013 at 12:42:33AM -0800, Valery Reznic wrote:
>>  ----- Original Message -----
>>  > From: Baruch Siach <baruch at tkos.co.il>
>>  > To: Valery Reznic <valery_reznic at yahoo.com>
>>  > Cc: shimi <linux-il at shimi.net>; linux-il 
> <linux-il at cs.huji.ac.il>
>>  > Sent: Tuesday, January 15, 2013 9:33 AM
>>  > Subject: Re: /proc/sys/vm/mmap_min_addr missing
>>  > 
>>  > On Mon, Jan 14, 2013 at 11:24:27PM -0800, Valery Reznic wrote:
>>  >>  > From: shimi <linux-il at shimi.net>
>>  >>  >To: Valery Reznic <valery_reznic at yahoo.com> 
>>  >>  >Cc: linux-il <linux-il at cs.huji.ac.il> 
>>  >>  >Sent: Tuesday, January 15, 2013 6:21 AM
>>  >>  >Subject: Re: /proc/sys/vm/mmap_min_addr missing
>>  >>  > 
>>  >>  >
>>  >>  >On Mon, Jan 14, 2013 at 11:40 PM, Valery Reznic 
>>  > <valery_reznic at yahoo.com> wrote:
>>  >>  >
>>  >>  >Recently I stumbled upon some mystery that I can't 
> understand.
>>  >>  >>My Google search bring no results.
>>  >>  >>
>>  >>  >>I have 3 VM with different Linuxes that run under QEMU 
> and now I 
>>  > noticed that
>>  >>  >>all of them don't have /proc/sys/vm/mmap_min_addr 
> files (/proc 
>>  > is mounted)
>>  >>  > 
>>  >>  >Are you emulating ARM on the guests by any chance?
>>  >>  I am running Fedora 12 ARM, Fedora Core 3 x86-64, and debian ARM
>>  >>  I don't remember debian version, but it's ARM OABI
>>  > 
>>  > mmap_min_addr first appeared in kernel version 2.6.23, commit ed032189 
> 
>>  > (security: Protection for exploiting null dereference using mmap). 
> What kernel 
>>  > versions are you running in your virtualized machines?
>>  My host with Fedora 12 x86-64
>>  Linux Fedora8 2.6.32.26-175.fc12.x86_64 #1 SMP Wed Dec 1 21:39:34 UTC 2010 
> x86_64 x86_64 x86_64 GNU/Linux
>> 
>>  has mmap_min_addr
> 
> No problem here.
> 
>>  Fedora 3 x86-64 with kernel 2.6.9-1.667 also has not mmap_min_addr
> 
> No problem here either (kernel too old).
> 
>>  Fedora 12 ARM with kernel 
>> 
>>  uname -a
>>  Linux fedora-arm 2.6.24-rc7 #1 Wed Jan 16 02:28:08 CET 2008 armv5tel 
> armv5tel armv5tel GNU/Linux
>> 
>>  has not
> 
> I now see that the original commit (ed032189) made mmap_min_addr depend on 
> CONFIG_SECURITY. Do you have this enabled in your kernel configuration?
> 
>>  Debian ARM OABI I think, has kernel 2.4 (can't check it now)
> 
> baruch
> 
> -- 
>      http://baruch.siach.name/blog/                  ~. .~   Tk Open Systems
> =}------------------------------------------------ooO--U--Ooo------------{=
>    - baruch at tkos.co.il - tel: +972.2.679.5364, http://www.tkos.co.il -
>