Description
The Linux kernel is an important cornerstone of modern technology and thus a
significant target for malicious actors. Protecting it against various forms of attacks,
such as binary exploitation, requires substantial effort. A common protection strategy
for binary exploitation attacks is to harden the kernel, making it more difficult to turn a
vulnerability into an applicable exploit. One such hardening feature is Structure Layout
Randomization. However, because the randomization is performed statically at compile
time, its effectiveness against real-world attacks is limited. This thesis presents a novel
approach that uses ELF relocations to enable dynamic randomization of structure
layouts. Furthermore, it describes a Clang-based prototype developed as a proof of
concept and demonstrates that this approach incurs only a negligible runtime overhead.
Finally, this thesis discusses the steps required to turn the prototype into a practical,
production-ready feature. Thus, it offers a tangible contribution to the security of the
world’s most common operating system.
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