Disabling ASLR in Mac OS X Snow Leopard

Question

Essentially I want to disable ASLR in Mac OS X Snow Leopard and use gcc todo some buffer overflowing and stack overflows. Anyone know how to disable ASLR?

Leyes

I was going to say google it, but google just turns up your question. :( – Illuse

The aslr is kernel technology which needs only PIE code generation from gcc. Buffer overflow and stack overflow protection is wider than just ASLR. – Edythedythe

Answer 1

Asan authors listed several ways to disable ASLR in MacOS: https://code.google.com/p/address-sanitizer/issues/detail?id=29

For 10.6

export DYLD_NO_PIE=1 

For 10.7 and newer:

• "unset the MH_PIE bit in an already linked executable" with --no-pie flag of the script

  http://src.chromium.org/viewvc/chrome/trunk/src/build/mac/change_mach_o_flags.py?view=markup

• or link the program with --no_pie flag.

And there is also hard method used by gdb: http://reverse.put.as/2011/08/11/how-gdb-disables-aslr-in-mac-os-x-lion/

Edythedythe

Answer 2

You can set the environment variable "DYLD_NO_PIE". See "man dyld". This works on OS X 10.6 but not on 10.5.

Rubrician