From: Jan Braun <janbraun@gmx.de>
To: Laurent Bercot <ska-supervision@skarnet.org>
Cc: "supervision@list.skarnet.org" <supervision@list.skarnet.org>
Subject: Re: chpst -u and supplementary groups
Date: Wed, 21 Aug 2019 05:50:41 +0200 [thread overview]
Message-ID: <20190821035041.bhp55m5p4zjkr7wm@klumpi.ignorelist.com> (raw)
In-Reply-To: <em726f24bf-65ac-4568-b0ea-7699445df4e1@elzian>
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Laurent Bercot schrob:
> I don't think the historical behaviour is a *bug*, because the
> historical behaviour is documented and conforms to its documentation.
Well, let's say "misfeature" ;)
> It also comes from a time when supplementary groups weren't used as
> much as they are today.
>
> It's just that not having supplementary groups can defeat intuitive
> expectations when performing a group permissions check. That does not
> happen every day, but it does happen sometimes. s6-setuidgid had the
> same behaviour as setuidgid until I got bitten by that very problem,
> at which point I realized that "user identity" is not only uid and gid
> as it is for files, but also supplementary groups, and so I added
> supplementary groups support to s6-*uidgid. But it had been years
> until I found it necessary.
Ok, that's the kind of answer I was hoping for, thanks.
> So, YMMV. I'd say supplementary groups support is useful and allows
> the tool to better match user intuition, so it has value. But is it
> *mandatory* for correctness? You decide.
I don't need to decide that. :) I already knew that *I* needed
supplementary group support. The only question was whether I should
implement it in runit's source code, or by piping the output of getent
through sed, and writing "chpst -u `userid acc` prog..." in my
runscripts as a matter of habit. And now the former sounds like the more
reasonable course of action. I'll go have a look at the code...
cheers,
Jan
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next prev parent reply other threads:[~2019-08-21 3:50 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-19 12:08 Jan Braun
2019-08-19 19:33 ` Steve Litt
2019-08-19 22:06 ` Bougy Man
2019-08-20 7:25 ` Jonathan de Boyne Pollard
2019-08-20 10:04 ` Jan Braun
2019-08-20 18:21 ` Laurent Bercot
2019-08-21 3:50 ` Jan Braun [this message]
2019-08-20 18:25 ` Cameron Nemo
2019-08-21 3:22 ` Jan Braun
2019-08-21 22:26 ` Steve Litt
2019-08-27 23:44 Jeff
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