linux-kernel - why is text address constant with full randomization?

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Date:	Tue, 15 Sep 2015 16:36:11 +0800
From:	慕冬亮 <mudongliangabcd@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: why is text address constant with full randomization?

First, my linux kernel is Linux 114-212-83-136 4.1.0-2-amd64.
Second, I copy /bin/cat in system to mycat , and see the address space
layout below.

mdl@...-212-83-136:~$ ./mycat /proc/self/maps
00400000-0040c000 r-xp 00000000 08:03 1046776
 /home/mdl/mycat
0060b000-0060c000 r--p 0000b000 08:03 1046776
 /home/mdl/mycat
0060c000-0060d000 rw-p 0000c000 08:03 1046776
 /home/mdl/mycat
01da7000-01dc8000 rw-p 00000000 00:00 0
 [heap]
......

The starting address of executable image is constant with my aslr
configuration 2 (full randomization).
I think text segment should be inconstant to defeat the attack like
reusing text code!
Is it related to fixing offset2lib attack?
Thanks for any help!
    - mudongliang
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