ABSTRACT
Position-independent executables (PIEs) are the last step on the journey to a fully randomised address space on OpenBSD, with the goal of providing improved defense against return-oriented programming. This paper details the measures undertaken to successfully make this conversion on a broad, system-wide scale. It also provides a perspective on both the future of practically deployed ROP mitigations and the prevalence of such features (including PIE) on other operating systems, such as *BSD, Linux and Windows.
Position-independent executables (PIEs) are the last step on the journey to a fully randomised address space on OpenBSD, with the goal of providing improved defense against return-oriented programming. This paper details the measures undertaken to successfully make this conversion on a broad, system-wide scale. It also provides a perspective on both the future of practically deployed ROP mitigations and the prevalence of such features (including PIE) on other operating systems, such as *BSD, Linux and Windows.
more here.............http://www.openbsd.org/papers/asiabsdcon2015-pie-paper.pdf