Linux kernel security is a very complex topic. Some defence technologies are provided by the Linux kernel mainline. Others are going out‑of‑tree for various reasons (some of them are commercial, for example). Plus there are kernel defences that depend on special hardware features.
It would certainly be convenient to have a graphical representation of the current state of Linux kernel security.
So I've created a Linux Kernel Defence Map showing the relationships between:
- Vulnerability classes
- Exploitation techniques
- Bug detection mechanisms
- Defence technologies
N.B. The node connections don't mean "full mitigation." Rather, each connection represents some kind of relationship. So this map should help to navigate the documentation and Linux kernel sources. It also provides the Common Weakness Enumeration (CWE) numbers for vulnerability classes.
This map is written in the DOT language, which makes maintenance and updating in Git very convenient. The diagram is generated using GraphViz with the following command:
dot -Tsvg linux-kernel-defence-map.dot -o linux-kernel-defence-map.svg
So there are plenty of Linux kernel hardening config options. A lot of them are not enabled by the major distros. We have to enable these options ourselves to make our systems more secure.
But nobody likes verifying configs manually. So I've created the kconfig-hardened-check.py that checks security hardening options in the Linux kernel Kconfig option list. You are welcome to try it.
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Grsecurity features:
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The State of Kernel Self Protection by Kees Cook:
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Linux kernel security documentation:
https://www.kernel.org/doc/html/latest/security/self-protection.html
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Linux kernel mitigation checklist by Shawn C:
https://github.com/hardenedlinux/grsecurity-101-tutorials/blob/master/kernel_mitigation.md
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Trends, challenge, and shifts in software vulnerability mitigation by MSRC:
https://github.com/Microsoft/MSRC-Security-Research/tree/master/presentations/2019_02_BlueHatIL
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Linux Kernel Runtime Guard (LKRG) threat model:
