ext4 bug?

From: Jörg-Volker Peetz
Date: Mon Nov 20 2023 - 09:03:46 EST


Hi,
some files got there modification timestamp changed to 'Sun 6 Jan 16:04:34 CET 2109' out of a blue. One directory has modification time stamp 'Sun 6 Jan 15:40:00 CET 2109' and three files have 'Sun 6 Jan 16:01:22 CET 2109', 'Sun 6 Jan 16:04:20 CET 2109', and 'Sun 6 Jan 12:56:02 CET 2109'.
This was observed recently during a backup. A check with
find /usr -newermt 2023-11-21
found several (ca. 30) files and directories in '/usr', '/var', and in another partition '/home'. About 14 of the files are 'index.db' in '/var/cache/man'
This is a server running kernel 6.6.1 when this happened.
I have no clue why that happened and no idea how to reproduce.
What could cause this?

Regards,
Jörg.