Gentoo Hardened July meeting

gentoo-hardened-july-meeting

Sven Vermeulen Fri 01 August 2014

I failed to show up myself (I fell asleep - kids are fun, but deplete your energy source quickly), but that shouldn't prevent me from making a nice write-up of the meeting.

Toolchain

GCC 4.9 gives some issues with kernel compilations and other components. Lately, breakage has been reported with GCC 4.9.1 compiling MySQL or with debugging symbols. So for hardened, we'll wait this one out until the bugs are fixed.

For GCC 4.10, the --enable-default-pie patch has been sent upstream. If that is accepted, the SSP one will be sent as well.

In uclibc land, stages are being developed for PPC. This is the final architecture that is often used in embedded worlds that needed support for it in Gentoo, and that's now being finalized. Go blueness!

SELinux

A libpcre upgrade broke relabeling operations on SELinux enabled systems. A fix for this has been made part of libselinux, but a little too late, so some users will be affected by the problem. It's easily worked around (removing the *.bin files in the contexts/files/ directory of the SELinux configuration) and hopefully will never occur again.

The 2.3 userland has finally been stabilized (we had a few dependencies that we were waiting for - and we were a dependency ourselves for other packages as well).

Finally, some thought discussion is being done (not that there's much feedback on it, but every documented step is a good step imo) on the SELinux policy within Gentoo (and the principles that we'll follow that are behind it).

Kernel and grsecurity / PaX

Due to some security issues, the Linux kernel sources have been stabilized more rapidly than usual, which left little time for broad validation and regression testing. Updates and fixes have been applied since and new stabilizations occurred. Hopefully we're now at the right, stable set again.

The C-based install-xattr application (which is performance-wise a big improvement over the Python-based one) is working well in "lab environments" (some developers are using it exclusively). It is included in the Portage repository ^(if\ I\ understand\ the\ chat\ excerpts\ correctly)^ but as such not available for broader usage yet.

An update against elfix is made as well as there was a dependency mismatch when building with USE=-ptpax. This will be corrected in elfix-0.9.

Finally, blueness is also working on a GLEP (Gentoo Linux Enhancement Proposal) to export VDB information (especially NEEDED.ELF.2) as this is important for ELF/library graph information (as used by revdep-pax, migrate-pax, etc.). Although Portage already does this, this is not part of the PMS and as such other package managers might not do this (such as Paludis).

Profiles

Updates on the profiles has been made to properly include multilib related variables and other metadata. For some profiles, this went as easy as expected (nice stacking), but other profiles have inheritance troubles making it much harder to include the necessary information. Although some talks have arised on the gentoo-dev mailinglist about refactoring how Gentoo handles profiles, there hasn't been done much more than just talking :-( But I'm sure we haven't heard the last of this yet.

Documentation

Blueness has added information on EMULTRAMP in the kernel configuration, especially noting to the user that it is needed for Python support in Gentoo Hardened. It is also in the PaX Quickstart document, although this document is becoming a very large one and users might overlook it.