From mboxrd@z Thu Jan  1 00:00:00 1970
From: Julien Lepiller <julien@lepiller.eu>
Subject: bug#37744: Per-user profile directory hijack (CVE-2019-17365 for Nix)
Date: Wed, 16 Oct 2019 18:28:08 +0200
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To: 37744@debbugs.gnu.org, ludo@gnu.org, me@tobias.gr
Cc: guix-security@gnu.org

Le 16 octobre 2019 12:22:33 GMT+02:00, "Ludovic Court=C3=A8s" <ludo@gnu=2Eo=
rg> a =C3=A9crit :
>Hello!
>
>Here=E2=80=99s a patch that fixes the issue, partly based on what the Nix=
 folks
>did=2E
>
>For the client-connecting-over-TCP case, I added special handling:
>=E2=80=98set-build-options=E2=80=99 now passes a =E2=80=9Cuser-name=E2=80=
=9D property, potentially
>allowing to create =E2=80=98per-user/$USER=E2=80=99 at that point (like y=
ou suggested,
>Tobias=2E)
>
>In a cluster setup, it means that the machine that runs =E2=80=98guix-dae=
mon=E2=80=99
>must see the same users as the machines where its clients run, but
>that=E2=80=99s basically already what we expect:
><https://hpc=2Eguix=2Einfo/blog/2017/11/installing-guix-on-a-cluster/>=2E
>
>There=E2=80=99s one case that won=E2=80=99t be correctly handled: in a cl=
uster setup,
>an
>old client talking to a new daemon won=E2=80=99t provide info to create
>=E2=80=98per-user/$USER=E2=80=99, and thus =E2=80=98guix package=E2=80=99=
 & co=2E won=E2=80=99t be able to create
>the user=E2=80=99s profile it it doesn=E2=80=99t already exist=2E  I thin=
k that=E2=80=99s hard to
>avoid though=2E
>
>Thoughts?
>
>Thanks,
>Ludo=E2=80=99=2E

We could advise people to restart the service too, with e=2Eg=2E systemctl=
 restart guix-daemon