This research was conducted by Zach Miller, Todd Tannenbaum, and Ben Liblit.
Applications do not typically view the kernel as a source of bad
input. However, the kernel can behave in unusual (yet permissible)
ways for which applications are badly unprepared. We present
Murphy, a language-agnostic tool that helps developers
discover and isolate run-time failures in their programs by
simulating difficult-to-reproduce but completely-legitimate
interactions between the application and the kernel. Murphy makes
it easy to enable or disable sets of kernel interactions, called
gremlins, so developers can focus on the failure
scenarios that are important to them. Gremlins are implemented
ptrace interface, intercepting and
potentially modifying an application’s system call invocation
while requiring no invasive changes to the host machine.
We show how to use Murphy in a variety of modes to find different classes of errors, present examples of the kernel interactions that are tested, and explain how to apply delta debugging techniques to isolate the code causing the failure. While our primary goal was the development of a tool to assist in new software development, we successfully demonstrate that Murphy also has the capability to find bugs in hardened, widely-deployed software.
The full paper is available as a single PDF document. A suggested BibTeX citation record is also available.
See also the related USENIX ATC paper.