linux-kernel - Question regarding blocking set[ug]id on processes including via suid executables

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20200512094524.662gnls64rwjhct2@shells.gnugeneration.com>
Date:   Tue, 12 May 2020 02:45:24 -0700
From:   Vito Caputo <vcaputo@...garu.com>
To:     linux-kernel <linux-kernel@...r.kernel.org>
Subject: Question regarding blocking set[ug]id on processes including via
 suid executables

Hello folks,

I'm curious if someone knows a way to do this using existing linux
interfaces.

I'd like to create a login lacking the ability to switch uid/gid.

Even if the process has access to suid executables like /bin/su, and
the user has the root password, I'd like the descendant processes of
their login to be simply incapable of changing uid/gid, even when it's
in the form of running a program w/suid bit set on an existing and
accessible executable in the filesystem.  No matter what, it just
can't happen.

Do we have any such thing today?  I'd really like to be able to set
this on a specific user and all logins of that user are simply stuck
on that uid no matter what.

Thanks in advance,
Vito Caputo