From debian-user  Tue Aug 31 08:51:28 2021
From: Rainer Dorsch <ml () bokomoko ! de>
Date: Tue, 31 Aug 2021 08:51:28 +0000
To: debian-user
Subject: Re: Permission Questions
Message-Id: <8158548.ANDYCCed9e () h370>
X-MARC-Message: https://marc.info/?l=debian-user&m=163039990825535

Am Dienstag, 31. August 2021, 00:00:02 CEST schrieb Greg Wooledge:
> On Mon, Aug 30, 2021 at 09:29:14PM +0000, Andy Smith wrote:
> > Hello,
> > 
> > On Mon, Aug 30, 2021 at 05:07:16PM -0400, Greg Wooledge wrote:
> > > unicorn:~$ strace bash -c 'echo stuff >> /tmp/123'
> > > [...]
> > > openat(AT_FDCWD, "/tmp/123", O_WRONLY|O_CREAT|O_APPEND, 0666) = -1
> > > EACCES (Permission denied)
> > > 
> > > As far as I can see, this is a kernel bug.  Unless I'm overlooking
> > > something...?
> > 
> > I think it's the sysctl fs.protected_regular:
> >     https://unix.stackexchange.com/a/503169
> 
> I think you're right.  The changed behavior doesn't happen in /srv (only
> in /tmp), nor does it happen on a buster system.
> 
> According to <https://www.spinics.net/lists/fedora-devel/msg252453.html>
> and <https://github.com/systemd/systemd/blob/main/NEWS>, the change
> actually happened in... wait for it... systemd.
> 
> *sigh*

Hi Andy and Greg,

many thanks for you very helpful replies, that explains the behavior fully.

Rainer

-- 
Rainer Dorsch
http://bokomoko.de/