Using KASAN and UBSAN to find memory bugs
The Kernel Address Sanitizer (KASAN) is a port of the Address Sanitizer (ASAN) tooling of the Linux kernel. The ASAN project proved to be so useful in detecting memory-related defects that having similar abilities within the kernel was a no-brainer. ASAN is one of the few tools that could detect the buffer overread defect that was at the root of the (in)famous so-called Heartbleed exploit! See the Further reading section for a very interesting XKCD comic link that superbly illustrates the bug at the heart of Heartbleed.
Understanding KASAN – the basics
A few points on KASAN will help you understand more:
- KASAN is a dynamic – runtime – analysis tool; it works while the code runs. This should have you realize that unless the code actually runs (executes), KASAN will not catch any bugs. This underlines the importance of writing really good test cases (both positive and negative), and the use of fuzzing tools...
