[Buildroot] sysklogd 1.6: messages from klogd are logged to user facility

[Buildroot] sysklogd 1.6: messages from klogd are logged to user facility

[Andreas Hilse]

Dear Buildroot Team,

there is an issue with sysklogd 1.6 (buildroot 2020.02.3).

The package includes its own implementation of openlog/syslog/vsyslog in
src/syslog.c to be able to log kernel messages to the kern facility.
The included syslog/vsyslog functions are not the ones getting executed,
thus kernel messages are marked with the user facility when they arrive in
syslogd.
I guess there was a change in the Makefile or glibc 2.22-2.29 which
results in taking precedence for these functions compared to sysklogd
1.5.1 (buildroot 2016.08).

Can you suggest a workaround/patch for this or are there plans to move to
a newer version of sysklogd?
Or should we just switch to rsyslog/syslog-ng?

Thanks & best regards
Andreas Hilse

[Buildroot] sysklogd 1.6: messages from klogd are logged to user facility

[Thomas Petazzoni]

Hello Andreas,

On Wed, 5 Aug 2020 19:55:50 +0200 (CEST)
Andreas Hilse <andreas.hilse@ipcomm.de> wrote:

> there is an issue with sysklogd 1.6 (buildroot 2020.02.3).
> 
> The package includes its own implementation of openlog/syslog/vsyslog in
> src/syslog.c to be able to log kernel messages to the kern facility.
> The included syslog/vsyslog functions are not the ones getting executed,
> thus kernel messages are marked with the user facility when they arrive in
> syslogd.
> I guess there was a change in the Makefile or glibc 2.22-2.29 which
> results in taking precedence for these functions compared to sysklogd
> 1.5.1 (buildroot 2016.08).
> 
> Can you suggest a workaround/patch for this or are there plans to move to
> a newer version of sysklogd?
> Or should we just switch to rsyslog/syslog-ng?

I am not really familiar with the internals of sysklogd, but there are
definitely newer versions available:

  https://github.com/troglobit/sysklogd/releases

Have you tried if version >= 2.0 would fix your issue ? It seems like
version 2.0 is really a major rewrite.

In any case, we would very much welcome Buildroot patches to update
sysklogd to a newer version.

Best regards,

Thomas
-- 
Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

[Buildroot] sysklogd 1.6: messages from klogd are logged to user facility

[Andreas Hilse]

Hello Thomas,

> Have you tried if version >= 2.0 would fix your issue ? It seems like
> version 2.0 is really a major rewrite.
> 
> In any case, we would very much welcome Buildroot patches to update
> sysklogd to a newer version.

I hoped someone already ran into this issue and fixed it.
I will try to upgrade to the rewritten 2.0 version then.

Best regards
Andreas

[Buildroot] sysklogd 1.6: messages from klogd are logged to user facility

[Andreas Hilse]

Hello Thomas,

Latest sysklogd 2.1.2 fixes the issue.

I'm trying to upgrade the sysklogd package and like to clarify some things
before submitting a patch.

Package now provides its own logger tool which could interfere with the
same from busybox or util-linux.
I already made it a selectable option in the Config.in but is there
anything to be done concerning busybox/util-linux?

klogd has been removed from the package, functionality is now in syslogd.

Best regards
Andreas

[Buildroot] sysklogd 1.6: messages from klogd are logged to user facility

[Thomas Petazzoni]

Hello Andreas,

On Mon, 10 Aug 2020 10:39:06 +0200 (CEST)
Andreas Hilse <andreas.hilse@ipcomm.de> wrote:

> Latest sysklogd 2.1.2 fixes the issue.
> 
> I'm trying to upgrade the sysklogd package and like to clarify some things
> before submitting a patch.
> 
> Package now provides its own logger tool which could interfere with the
> same from busybox or util-linux.

Well, the overlap with Busybox already exists, and that's why Busybox has:

BUSYBOX_DEPENDENCIES = \
	...
        $(if $(BR2_PACKAGE_SYSKLOGD),sysklogd) \

This way Busybox is installed *after* sysklogd, and Busybox
installation process is careful enough to not overwrite already
installed binaries.

However, klogd being removed from sysklogd, I'm not sure how this will
end up working: it is possible that Busybox will install its own klogd
symlink anyway.


> I already made it a selectable option in the Config.in but is there
> anything to be done concerning busybox/util-linux?

What have you made selectable ?

Thomas
-- 
Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

[Buildroot] sysklogd 1.6: messages from klogd are logged to user facility

[Andreas Hilse]

Hello Thomas,

> BUSYBOX_DEPENDENCIES = \
> 	...
>         $(if $(BR2_PACKAGE_SYSKLOGD),sysklogd) \
> 
> This way Busybox is installed *after* sysklogd, and Busybox installation
> process is careful enough to not overwrite already installed binaries.

> However, klogd being removed from sysklogd, I'm not sure how this will
> end up working: it is possible that Busybox will install its own klogd
> symlink anyway.

It does install its own klogd symlink, but its S02klogd script does not
get installed because BR2_PACKAGE_SYSKLOGD is selected, so it won't be
started.
I just checked: the same goes for rsyslog (busybox klogd link gets
installed). So it should be okay for sysklogd, too?


> What have you made selectable ?
The sysklogd logger utility; configure has an option:
  --without-logger        Build without extended logger tool, default:
enabled

In case of the logger utility both busybox link (/usr/bin/logger) and
sysklogd binary (/bin/logger) get installed.

Best regards
Andreas