Full-system fuzzing – introducing TriforceAFL
As previously mentioned, TriforceAFL is a tool that combines the capabilities of two powerful tools, AFL and QEMU, to apply fuzzing at the kernel level of an OS. In this section, we will delve deeper into the internals of TriforceAFL to understand how it works.
AFL utilizes modified versions of gcc, g++, clang, or clang++ during compilation to instrument the code at the entrance and exits of basic code blocks. These basic blocks are pieces of code with no branches or other conditions that may divert the control flow and thus execute in sequence. This instrumentation makes it easier to understand crash dumps and backtrack the stack when the fuzzed program reports a crash. An instrumented binary contains the necessary code for applying fuzzing and tracking program edge cases for code coverage. Given a set of inputs, AFL executes the binary executable program and collects traces and possible crashes. AFL then applies different mutation...
