From: "Laurent Bercot" <ska-supervision@skarnet.org>
To: "supervision@list.skarnet.org" <supervision@list.skarnet.org>
Subject: Re: chpst -u and supplementary groups
Date: Tue, 20 Aug 2019 18:21:09 +0000 [thread overview]
Message-ID: <em726f24bf-65ac-4568-b0ea-7699445df4e1@elzian> (raw)
In-Reply-To: <20190820100433.rlioufyvxodvwkpc@klumpi.ignorelist.com>
>Yes. Apparently everyone re-implementing daemontools does something like
>this. So that brings me back to my original question: is there consensus
>that the historical behaviour is a bug? Or are there valid use cases¹?
I don't think the historical behaviour is a *bug*, because the
historical behaviour is documented and conforms to its documentation.
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.
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.
--
Laurent
next prev parent reply other threads:[~2019-08-20 18:21 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 [this message]
2019-08-21 3:50 ` Jan Braun
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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