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From: Thorsten Kukuk <kukuk@suse.com>
To: distributions@lists.linux.dev
Subject: Y2038, glibc and utmp/utmpx on 64bit architectures
Date: Fri, 3 Mar 2023 11:46:47 +0100	[thread overview]
Message-ID: <20230303104647.GA20891@suse.com> (raw)


Hi,

I hope everybody is aware of the Y2038 problem. And not only for 32bit
architectures, but also 64bit architectures are not ready today, at
least not if they use glibc.
glibc uses for compatibility with 32bit userland applications 32bit
values for time_t and other variables even on 64bit systems.
Affected is everything around utmp/utmpx, wtmp/wtmpx and lastlog.

I wrote a blog about how to solve that for utmp/utmpx by using the data
from systemd-logind instead:
https://www.thkukuk.de/blog/Y2038_glibc_utmp_64bit/

A detailed analysis also for wtmp and lastlog, which have the same
problems, can be found here:
https://github.com/thkukuk/utmpx/blob/main/Y2038.md


   Thorsten

-- 
Thorsten Kukuk, Distinguished Engineer, Senior Architect, Future Technologies
SUSE Software Solutions Germany GmbH, Frankenstraße 146, 90461 Nuernberg, Germany
Managing Director: Ivo Totev, Andrew Myers, Andrew McDonald, Martje Boudien Moerman
(HRB 36809, AG Nürnberg)

             reply	other threads:[~2023-03-03 10:46 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-03 10:46 Thorsten Kukuk [this message]
2023-03-03 16:51 ` Y2038, glibc and utmp/utmpx on 64bit architectures A. Wilcox
     [not found] ` <3067bd0ec5134b039cdb8be9db8da8e5@DB6PR04MB3255.eurprd04.prod.outlook.com>
2023-03-03 17:07   ` Thorsten Kukuk
2023-03-03 20:09     ` Anna
2023-03-03 20:25     ` Bruno Haible
     [not found]     ` <c420abff6abd43cabac8c2fa5d812091@DB6PR04MB3255.eurprd04.prod.outlook.com>
2023-03-03 20:55       ` Thorsten Kukuk
2023-03-03 22:11         ` Bruno Haible

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