Gentoo Hardened meeting 201310


Sven Vermeulen Thu 24 October 2013

We gathered online again to talk about the progress, changes and other stuff related to the Gentoo Hardened project.

New Developer

We welcomed Zero_Chaos as a new addition to our team. Big welcome, with the usual IRC kick in between, ensued.


GCC 4.8.x is unmasked and ready for testing. The ASAN problem however is not resolved and it doesn't look like upstream wants to provide the fix for this. As a result, if you want to use ASAN, you will need to disable UDEREF in the kernel.

A difficult problem here is that, if a user forgets to disable UDEREF, then building with ASAN will fail. If he disabled UDEREF and uses ASAN, then booting into a UDEREF enabled kernel will fail. If he starts building with ASAN on UDEREF kernels, things will break. Its ugly, and unless the ASAN code is changed to support other technologies using the address space layout information, it will remain mutually exclusive.

For now, we'll properly document the situation.

GCC 4.9 will end its stage1 development phase on November 21st.

The uclibc stages are currently built with GCC-4.7.3-r1, except for the MIPS architectures which use GCC 4.8.1-r1.
The stages are built once every two months, give or take.

Kernel grSec/PaX

Standard maintenance, such as keeping up with upstream changes, has taken place. The XATTR problems with the install binary/phase has not been resolved yet due to time constraints. First focus will be on writing the C-based wrapper to see if this significantly speeds things up.


There is ambiguity of the meaning or use of the pax_kernel USE flag. It seems to be used for multiple, exclusive things, like limiting builds on PaX kernels or limiting run-time behavior on PaX kernels. To build Gentoo images, developers need to set pax_kernel on some packages and disable it on others in order for the image to build properly.

<@blueness> USE=pax_kernel in the case of userland should apply patches etc, that fix the code
            so that it won't trip pax protection eg mprotect
<@blueness> in the case of kernel modules, it can't mean that obviously!

One of the mentioned problems is that some ebuilds only enable pax markings when pax_kernel is set. However, that shouldn't be done conditionally. PaX markings can be done even without a PaX kernel.

Zero_Chaos (new developers always have the necessary energy) will try to update ebuilds where applicable.

SELinux and System Integrity

Nothing worth mentioning here.


Many users were using hardened profiles on the desktop. In the past, we had the desktop/hardened profiles removed (referring users to the regular hardened profiles and asking them to update their system with the USE flags (and other settings) they want for their desktop. Apparently, this is giving some problems for some users, so the idea is to reinstate the desktop/hardened profiles where the hardened settings overrule the desktop settings.

However, we should take care of tackling the issues we had in the past (which is the reason why we removed the profiles in the first place). It is recommended that we discuss this outside the IRC meeting to make sure we don't reintroduce the issues again while using a flexible approach.

That's it. A big thanks to the developers, contributors and thousands of users!