This addresses a potential security issue, where a compromised
service could trick the activation code in changing the permissions,
owner and group of arbitrary files. However, this patch is
currently only a partial fix, due to a TOCTTOU (time-of-check to
time-of-use) race, which can be fixed once guile has bindings
to openat and friends.
Fixes: <https://lists.gnu.org/archive/html/guix-devel/2021-01/msg00388.html>
* gnu/build/activation.scm: new procedure 'mkdir-p/perms'.
* gnu/services/authentication.scm
(%nslcd-activation, nslcd-service-type): use new procedure.
* gnu/services/cups.scm (%cups-activation): likewise.
* gnu/services/dbus.scm (dbus-activation): likewise.
* gnu/services/dns.scm (knot-activation): likewise.
Signed-off-by: Ludovic Courtès <ludo@gnu.org>