Brussels / 31 January & 1 February 2026

schedule

I spent my summer reverse engineering ESXi VMFS, you?


Someone on the internet told me I was wrong. Or, well, that my code was wrong. And a totally normal response to that is to spend over a month reverse engineering proprietary kernels and kernel modules.

How did we get here? Well, once upon a time I was fed up with all the bugs in vmfs-tools and vmfs6-tools, so I wrote my own VMFS implementation. Except that I took a lot of shortcuts, and in doing so I inherited some of the same bugs! Fast forward to 2025, and those bugs are finally catching up to me.

Join me as I go over the excruciating process of gathering decade old ESX(i) installation media, hunting for debug symbols, and trying to piece together how VMFS actually works. Oh, and fix that bug, of course.

Speakers

Photo of Erik Schamper Erik Schamper

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