Back when Intel introduced the 80286, they didn't quite document everything right away. Errata were needed. Then the 80386 changed things. And then someone convinced them to add just one more feature at the last minute, which didn't get documented properly again.
The History of a Security Hole takes a look at the problems introduced by the I/O Permission Bitmap (IOPB) in the 80286, and how fallout from the implementation caused a security hole in all versions of OpenBSD up to 6.3 and NetBSD up to 4.4.
Conclusion? This programming thing is hard.
(Score: 2) by martyb on Friday September 07 2018, @12:01AM
Thanks for the reply!
A minor nit, if I may? The quote you are referencing actually came from "Ignition! An Informal History of Liquid Rocket Propellants" written by John Drury Clark [wikipedia.org]. That said, (written?), that work is also a most interesting read! Highly recommended, as well!
Wit is intellect, dancing.