Linux Security Summit North America 2020

Code integrity is widely recognized as one of the most effective security mitigations for modern threats, especially those targeting high-value systems. Authoring, maintaining, and enforcing a system-wide integrity policy can be challenging for system builders today.

We'll present our work including a new LSM, Integrity Policy Enforcement (IPE), and in-kernel signature verification of DM-Verity root hashes. We'll also demonstrate a fully worked example and discuss challenges
such as dynamic code generation and providing authentication mechanisms around data integrity.

The IPE LSM provides a flexible integrity policy mechanism that allows integrity verification requirements to be specified for all files on the system and from an arbitrary number of filesystems. A variety of integrity
verification mechanisms may be utilized as the framework is easy to extend.