From 8b89628a10af3863bfc97872912e9da4076a5929 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Fri, 3 Feb 2017 09:41:53 -0500
Subject: [PATCH] core/execute: set HOME, USER also for root users

This changes the environment for services running as root from:

LANG=C.utf8
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
INVOCATION_ID=ffbdec203c69499a9b83199333e31555
JOURNAL_STREAM=8:1614518

to

LANG=C.utf8
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
HOME=/root
LOGNAME=root
USER=root
SHELL=/bin/sh
INVOCATION_ID=15a077963d7b4ca0b82c91dc6519f87c
JOURNAL_STREAM=8:1616718

Making the environment special for the root user complicates things
unnecessarily. This change simplifies both our logic (by making the setting
of the variables unconditional), and should also simplify the logic in
services (particularly scripts).

Fixes #5124.
---
 man/systemd.exec.xml | 4 +---
 src/core/execute.c   | 5 +----
 2 files changed, 2 insertions(+), 7 deletions(-)

diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml
index 699f6e263f0..8079b4b2106 100644
--- a/man/systemd.exec.xml
+++ b/man/systemd.exec.xml
@@ -1694,9 +1694,7 @@
         <term><varname>$SHELL</varname></term>
 
         <listitem><para>User name (twice), home directory, and the
-        login shell. The variables are set for the units that have
-        <varname>User=</varname> set, which includes user
-        <command>systemd</command> instances. See
+        login shell. See
         <citerefentry project='die-net'><refentrytitle>passwd</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
         </para></listitem>
       </varlistentry>
diff --git a/src/core/execute.c b/src/core/execute.c
index 47cc4311c1c..67b54a3bece 100644
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -815,13 +815,10 @@ static int get_fixed_user(const ExecContext *c, const char **user,
 
         assert(c);
 
-        if (!c->user)
-                return 0;
-
         /* Note that we don't set $HOME or $SHELL if they are not particularly enlightening anyway
          * (i.e. are "/" or "/bin/nologin"). */
 
-        name = c->user;
+        name = c->user ?: "root";
         r = get_user_creds_clean(&name, uid, gid, home, shell);
         if (r < 0)
                 return r;
-- 
2.47.3