Re: [RFC] Null Namespaces
Christian Brauner <[email protected]> Mon, 29 Jun 2026 12:39:56 +0200
| Newsgroups | org.kernel.vger.linux-api,org.kernel.vger.linux-arch,org.kernel.vger.linux-fsdevel,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <20260629-zoomen-tragweite-redakteur-dc6c41c9c151@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".