Comment by kelnos
3 days ago
I don't think we should set our expectations based on an extreme outlier. qmail is special, and we can't expect most software to get to its level of security/safety.
Put another way: if you have to rely on programmer skill or attention to detail in order to guarantee something, that will always be a losing bet, on average. The existence of a tiny percentage of programmers that can clear that high bar does not make it a valid strategy.
Splitting programs into mutually untrusting modules is a plausible alternative to memory safety in programming languages.
Also in a program similar to qmail, memory safety alone is not sufficient, a lot of bugs in sendmail were related to complexity issues.
If only there was an OS design architecture that would follow such approach from the ground up....
Why can't we write everything like qmail?