Stephen Smalley

Pluggable Security

Submitted by Jeremy
on October 1, 2007 - 5:49am
Linux news

"I think the decision to merge Smack is something that needs to be considered in the wider context of overall security architecture," suggested James Morris following Andrew Morton's recent comment that he plans to merge the functionality in the upcoming 2.6.24 kernel. While James had no complaints about Smack itself, he expressed concerns regarding the pluggable nature of LSM, which is used by Smack, cautioning, "if LSM remains, security will never be a first class citizen of the kernel," adding, "on a broader scale, we'll miss the potential of Linux having a coherent, semantically strong security architecture." He noted that he'd rather see SELinux as the sole Linux security framework, "merging Smack, however, would lock the kernel into the LSM API. Presently, as SELinux is the only in-tree user, LSM can still be removed."

Linus Torvalds firmly stated, "LSM stays in. No ifs, buts, maybes or anything else." He explained, "you security people are insane. I'm tired of this 'only my version is correct' crap. The whole and only point of LSM was to get away from that." Linus continued, "I guess I have to merge AppArmor and SMACK just to get this *disease* off the table. You're acting like a string theorist, claiming that t here is no other viable theory out there. Stop it. It's been going on for too damn long." Stephen Smalley responded, "you argued against pluggable schedulers, right? Why is security different?" Linus explained:

"Schedulers can be objectively tested. There's this thing called 'performance', that can generally be quantified on a load basis.

"Yes, you can have crazy ideas in both schedulers and security. Yes, you can simplify both for a particular load. Yes, you can make mistakes in both. But the *discussion* on security seems to never get down to real numbers. So the difference between them is simple: one is 'hard science'. The other one is 'people wanking around with their opinions'."