Subject: Re: bug#929: rsyslog: segfaults with latest libc6 (2.42-4)

From: Mark Hindley <[email-masked]>
Date: Thu, 4 Dec 2025 13:44:01 +0000

Dimitris

Thanks.

On Thu, Dec 04, 2025 at 02:15:45PM +0200, Dimitris T. wrote:
> Package: rsyslog
> Version: 8.2510.0-5devuan1
> Severity: grave
> Justification: renders package unusable
> 
> Hey,
> since upgrading libc6 today, rsyslog fails with following message : 
> 
> # /usr/sbin/rsyslogd -n -iNONE
> /usr/sbin/rsyslogd: Relink `/usr/lib/x86_64-linux-gnu/libfastjson.so.4' with `/usr/lib/x86_64-linux-gnu/libm.so.6' for IFUNC symbol `modf'
> Segmentation fault

I have to admit to not understanding fully the intricacies of the linking and
symbols here.

There is an apparently equivalent Gentoo bug[1] that suggests this should be
resolved in libfastjson4. In other words it is for Debian to resolve.

Let me do some more research.

Mark

[1]  https://bugs.gentoo.org/961289