Error starting dbus-broker-launch

[mthmulders]

On one ArchLinux installation I have, dbus-broker fails to start.

Output of journalctl -u dbus-broker:

Mar 05 02:19:20 alarm dbus-broker-launch[846]: ERROR util_audit_drop_permissions @ ../dbus-broker-35/src/util/audit.c +86: Invalid argument
Mar 05 02:19:20 alarm dbus-broker-launch[845]: ERROR service_add @ ../dbus-broker-35/src/launch/service.c +1011: Transport endpoint is not connected
Mar 05 02:19:20 alarm dbus-broker-launch[845]:       launcher_add_services @ ../dbus-broker-35/src/launch/launcher.c +805
Mar 05 02:19:20 alarm dbus-broker-launch[845]:       launcher_run @ ../dbus-broker-35/src/launch/launcher.c +1416
Mar 05 02:19:20 alarm dbus-broker-launch[845]:       run @ ../dbus-broker-35/src/launch/main.c +152
Mar 05 02:19:20 alarm dbus-broker-launch[845]:       main @ ../dbus-broker-35/src/launch/main.c +178
Mar 05 02:19:20 alarm dbus-broker-launch[845]: Exiting due to fatal error: -107

As an end user, I have no clue what the problem is or where to even start debugging. I wouldn't mind providing more info, if only I knew where to look...

[dvdhrm]

Thanks for the report! This is an assertion failure in dbus-broker. prctl(PR_CAP_AMBIENT, ...) is returning EINVAL, which is unexpected and not supported. Hence you see the backtrace and error message.

Are you running the default ArchLinux kernel? What kernel version is this? Do you run with any LSMs enabled? That is, SELinux, AppArmor, etc?

[mthmulders]

I'm running a port of ArchLinux, ArchLinux ARM, because the device is an CuBox-i which is not supported by mainline ArchLinux. This also explains the old kernel version:

Linux alarm 3.14.79-3-ARCH #1 SMP Wed May 10 01:50:38 UTC 2017 armv7l GNU/Linux

As far as I can tell, I have neither SELinux nor AppArmor installed:

[alarm@alarm ~]$ sudo sestatus
sudo: sestatus: command not found
[alarm@alarm ~]$ sudo apparmor_status
sudo: apparmor_status: command not found

[teg]

dbus-broker requires Linux 4.17, so this is not likely to work / get fixed.

[mthmulders]

Wow, that never appeared to me. Thanks for pointing that out!

I took the guess and tried the generic armv7 kernel from ArchLinux ARM and it boots fine. More importantly, it lets dbus-broker boot. So I think that resolves my issue!

[teg]

Nice! Great to hear :)