OpenBSD’s Propolice stack protector origins

"In a detailed retrospective by longtime OpenBSD developer Miod Vallat, the early development of Propolice—a stack protection mechanism—is explored as a pivotal shift in the project’s security philosophy. The article highlights how OpenBSD transitioned from focusing solely on bug-free code to actively making exploitation more difficult, even when vulnerabilities existed. Vallat explains the technical challenges of implementing Propolice across diverse architectures, including now-obsolete systems like OpenBSD/vax, ensuring broad compatibility. Though the term Propolice has faded from common use, the work laid critical groundwork for modern stack protection techniques in OpenBSD and beyond. The piece serves as both a historical account and a technical deep dive into the evolution of defensive programming practices within the project" BSD Weekly

http://miod.online.fr/software/openbsd/stories/propolice.html