Debugging use-after-free with RR reverse execution

Published: Nov 25 2015

RR is a very useful tool for debugging. It can record the execution of a program and then replay the exact same execution at will inside a debugger. One very useful extra power available since 4.0 is the support for efficient reverse execution which can be used to find the root cause of a bug in your program by rewinding time. In this example, we reverse-execute a program from a case of use-after-free in order to find where the block of memory was freed.

Sample watchpoints or breakpoints with GDB (and FlameGraph)

Published: Jul 17 2014

GDB can be used to get the stack each time a breakpoint is reached.

Profiling and optimising with Flamegraph

Published: May 23 2014

Flamegraph is a software which generates SVG graphics to visualise stack-sampling based profiles. It processes data collected with tools such as Linux perf, SystemTap, DTrace.