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From: Rich Felker <dalias@libc.org>
To: "A. Wilcox" <awilfox@adelielinux.org>
Cc: musl@lists.openwall.com
Subject: Re: [musl] get/set*ent functions and real world applications
Date: Wed, 13 Oct 2021 09:56:10 -0400	[thread overview]
Message-ID: <20211013135609.GI7074@brightrain.aerifal.cx> (raw)
In-Reply-To: <F7E8D2A4-7449-4843-9D92-22FDA05C6154@adelielinux.org>

On Wed, Oct 13, 2021 at 01:16:30AM -0500, A. Wilcox wrote:
> On Oct 11, 2021, at 12:41 PM, Érico Nogueira <ericonr@disroot.org> wrote:
> > 
> > Things in /etc
> > can, theoretically, only be written to by root or at least trusted
> > users, so treating as entirely untrusted seems a bit over the top...
> 
> My understanding is that tcb exists explicitly to make these files
> modifiable by non-root users, to make the shadow tools unprivileged.
> 
> I don't recall if GECOS or group fields are included in tcb, or if
> it is only the password itself. If the other fields are included,
> this is a much more important bug than otherwise.

Users necessarily can't change their group memberships. They can't
change anything in passwd db at all, only shadow, and only for
themselves, and only if permissions are set so as to allow that.

Rich

      reply	other threads:[~2021-10-13 13:56 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-11 13:32 (GalaxyMaster)
2021-10-11 17:18 ` Érico Nogueira
2021-10-12  0:38   ` (GalaxyMaster)
2021-10-12 15:58     ` Érico Nogueira
2021-10-12 17:38       ` Érico Nogueira
2021-10-13  6:16   ` A. Wilcox
2021-10-13 13:56     ` Rich Felker [this message]

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