Re: [RFC] Null Namespaces

[Christian Brauner]

> The kernel rightfully has consolidated path resolution in a few key
> places as much as possible -- the internal `struct path` does not suffer
> from these issues. I barely modify those places to support null root and
> CWD, and because of that consolidation, we shouldn't expect new places
> to crop up in the future. (Duplicative path resolution logic is a bad
> idea whether or not we have a nascent, little-used NULL-cwd/root code
> path.) Therefore, I think existing code review, even among people
> totally ignorant of this feature, will protect us --- the vast majority
> of code will just be working with `struct path`, and be totally
> unaffected by this change.

I actually did laugh out loud reading this. I'm sorry, I can't really
take this argument seriously. May I introduce you to drivers/ for a
start and the history of path lookup exploits of the last - say 10
years.

You have to excuse me but it's a mixture of amusement and slight anger.
Amusement because this is really naive and thus also a bit endearing.
Anger because it single-handedly dismisses how big of an attack surface
and problem space path lookup is. The equivalent of every math
professor's "trivial. excercise left to the reader".