Library address randomization

[Dave Jones]

On Mon, Jan 26, 2009 at 12:14:10AM -0300, Ricardo Rolim wrote:
 > Hi there,
 > 
 > Apparently I'm not getting library address randomization for any
 > programs (compiled or not as PIE). Whereas the binary itself, stack
 > and heap are randomly getting their addresses changed from one
 > execution to the next, the library stands still at a predictable
 > location. Strangely enough I've got the expected results out of Ubuntu
 > 8.10. Here's one example:
 > 
 > [ricardo at localhost ~]$ cat /proc/sys/kernel/randomize_va_space
 > 2
 > [ricardo at localhost ~]$ cat /proc/sys/kernel/exec-shield
 > 1
 > [ricardo at localhost ~]$ echo 'int main(){}' > dummy.c
 > [ricardo at localhost ~]$ gcc -fpie -pie -o dummy dummy.c
 > [ricardo at localhost ~]$ ldd dummy
 > 	linux-gate.so.1 =>  (0x00130000)
 > 	libc.so.6 => /lib/libc.so.6 (0x00133000)
 > 	/lib/ld-linux.so.2 (0x00110000)
 > [ricardo at localhost ~]$ ldd dummy
 > 	linux-gate.so.1 =>  (0x00130000)
 > 	libc.so.6 => /lib/libc.so.6 (0x00133000)
 > 	/lib/ld-linux.so.2 (0x00110000)

What kernel version are you running?  Kyle fixed up some
of this code last week.

	Dave

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