LWN.net Logo

Volatile whether you like it or not

Volatile whether you like it or not

Posted Nov 5, 2012 20:25 UTC (Mon) by jimparis (subscriber, #38647)
In reply to: Volatile whether you like it or not by epa
Parent article: Many more words on volatile ranges

> This could be a generalization of the OOM killer. When memory is tight, some unlucky process is chosen and any pages it hasn't used recently are marked as volatile. It keeps running but if it tries to access one of those pages then boom! This might be a bit better than just killing it immediately.

That's a cool idea, but potentially a security risk via information leak -- if you use a lot of memory on a system and trigger the OOM killer, you can now determine how another process is behaving or treating its input by whether it goes boom or not. I can only think of contrived examples at the moment, but attackers are more clever.


(Log in to post comments)

Copyright © 2013, Eklektix, Inc.
Comments and public postings are copyrighted by their creators.
Linux is a registered trademark of Linus Torvalds