buildah: seccomp: config provided but seccomp not supported

Description

When running a command in a container, the process exits with the error :

container_linux.go:348: starting container process caused "seccomp: config provided but seccomp not supported"

I am not exactly sure it is a bug from buildah itself. I guess I have to somehow enable seccomp, but I don’t know how, and it seems to be already enabled :

$ zgrep SECCOMP /proc/config.gz
CONFIG_HAVE_ARCH_SECCOMP_FILTER=y
CONFIG_SECCOMP_FILTER=y
CONFIG_SECCOMP=y

So it might be an issue completely unrelated to seccomp altogether, but I lack the general knowledge to understand what is wrong, or where to look for clues.

Steps to reproduce the issue:

$ sudo buildah from fedora
Getting image source signatures
Copying blob sha256:a8ee583972c2295bb76704d4defe5116d5e4dd7ba3767aaa2cc8fcf71088ee06
 82.80 MiB / 82.80 MiB [===================================================] 26s
Copying config sha256:422dc563ca3260ad9ef5c47a1c246f5065d7f177ce51f4dd208efd82967ff182
 2.29 KiB / 2.29 KiB [======================================================] 0s
Writing manifest to image destination
Storing signatures
fedora-working-container
$ sudo buildah images
IMAGE ID             IMAGE NAME                                               CREATED AT             SIZE
422dc563ca32         docker.io/library/fedora:latest                          Nov 14, 2017 21:07     251 MB
$ sudo buildah containers
CONTAINER ID  BUILDER  IMAGE ID     IMAGE NAME                       CONTAINER NAME
5062084a1ad7     *     422dc563ca32 docker.io/library/fedora:latest  fedora-working-container
$ sudo buildah run fedora-working-container sh
container_linux.go:348: starting container process caused "seccomp: config provided but seccomp not supported"

Output of rpm -q buildah or apt list buildah:

I’m running Arch, and used yaourt to install buildah from git using this PKGBUILD. It builds buildah from the source of this repo, and as I installed it just now (to be sure it isn’t an issue already fixed), the version referes to the very last commit (46c1a54) as of now.

$ pacman -Q | grep buildah
buildah-git r478.46c1a54-1

Output of buildah version:

$ buildah -v                                                                                                                                                 
buildah version 0.11 (image-spec 1.0.0, runtime-spec 1.0.0)

Output of cat /etc/*release:

LSB_VERSION=1.4
DISTRIB_ID=Arch
DISTRIB_RELEASE=rolling
DISTRIB_DESCRIPTION="Arch Linux"
NAME="Arch Linux"
PRETTY_NAME="Arch Linux"
ID=arch
ID_LIKE=archlinux
ANSI_COLOR="0;36"
HOME_URL="https://www.archlinux.org/"
SUPPORT_URL="https://bbs.archlinux.org/"
BUG_REPORT_URL="https://bugs.archlinux.org/"

Output of uname -a:

Linux etndev 4.14.14-1-ARCH #1 SMP PREEMPT Fri Jan 19 18:42:04 UTC 2018 x86_64 GNU/Linux

Output of cat /etc/containers/storage.conf:

cat: /etc/containers/storage.conf: No such file or directory