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From c0f32feb77768aa76d8c813471b3484c93bc2651 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Fri, 5 Jan 2018 12:20:22 +0100
Subject: [PATCH] core: be stricter when handling PID files and MAINPID
sd_notify() messages
Let's be more restrictive when validating PID files and MAINPID=
messages: don't accept PIDs that make no sense, and if the configuration
source is not trusted, don't accept out-of-cgroup PIDs. A configuratin
source is considered trusted when the PID file is owned by root, or the
message was received from root.
This should lock things down a bit, in case service authors write out
PID files from unprivileged code or use NotifyAccess=all with
unprivileged code. Note that doing so was always problematic, just now
it's a bit less problematic.
When we open the PID file we'll now use the CHASE_SAFE chase_symlinks()
logic, to ensure that we won't follow an unpriviled-owned symlink to a
privileged-owned file thinking this was a valid privileged PID file,
even though it really isn't.
Fixes: #6632
(cherry picked from commit db256aab13d8a89d583ecd2bacf0aca87c66effc)
Resolves: #1663143
---
man/systemd.service.xml | 18 ++-
src/core/manager.c | 17 ++-
src/core/service.c | 166 ++++++++++++++++------
src/core/unit.h | 2 +-
test/TEST-20-MAINPIDGAMES/Makefile | 1 +
test/TEST-20-MAINPIDGAMES/test.sh | 81 +++++++++++
test/TEST-20-MAINPIDGAMES/testsuite.sh | 189 +++++++++++++++++++++++++
test/test-functions | 2 +-
8 files changed, 418 insertions(+), 58 deletions(-)
create mode 120000 test/TEST-20-MAINPIDGAMES/Makefile
create mode 100755 test/TEST-20-MAINPIDGAMES/test.sh
create mode 100755 test/TEST-20-MAINPIDGAMES/testsuite.sh
diff --git a/man/systemd.service.xml b/man/systemd.service.xml
index d147e449a6..565a783f72 100644
--- a/man/systemd.service.xml
+++ b/man/systemd.service.xml
@@ -221,16 +221,14 @@
<varlistentry>
<term><varname>PIDFile=</varname></term>
- <listitem><para>Takes an absolute file name pointing to the
- PID file of this daemon. Use of this option is recommended for
- services where <varname>Type=</varname> is set to
- <option>forking</option>. systemd will read the PID of the
- main process of the daemon after start-up of the service.
- systemd will not write to the file configured here, although
- it will remove the file after the service has shut down if it
- still exists.
- </para>
- </listitem>
+ <listitem><para>Takes an absolute path referring to the PID file of the service. Usage of this option is
+ recommended for services where <varname>Type=</varname> is set to <option>forking</option>. The service manager
+ will read the PID of the main process of the service from this file after start-up of the service. The service
+ manager will not write to the file configured here, although it will remove the file after the service has shut
+ down if it still exists. The PID file does not need to be owned by a privileged user, but if it is owned by an
+ unprivileged user additional safety restrictions are enforced: the file may not be a symlink to a file owned by
+ a different user (neither directly nor indirectly), and the PID file must refer to a process already belonging
+ to the service.</para></listitem>
</varlistentry>
<varlistentry>
diff --git a/src/core/manager.c b/src/core/manager.c
index 73d6c81fdb..3bca61d0b1 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -1658,11 +1658,18 @@ static int manager_dispatch_cgroups_agent_fd(sd_event_source *source, int fd, ui
return 0;
}
-static void manager_invoke_notify_message(Manager *m, Unit *u, pid_t pid, const char *buf, FDSet *fds) {
+static void manager_invoke_notify_message(
+ Manager *m,
+ Unit *u,
+ const struct ucred *ucred,
+ const char *buf,
+ FDSet *fds) {
+
_cleanup_strv_free_ char **tags = NULL;
assert(m);
assert(u);
+ assert(ucred);
assert(buf);
tags = strv_split(buf, "\n\r");
@@ -1674,7 +1681,7 @@ static void manager_invoke_notify_message(Manager *m, Unit *u, pid_t pid, const
log_unit_debug(u->id, "Got notification message for unit %s", u->id);
if (UNIT_VTABLE(u)->notify_message)
- UNIT_VTABLE(u)->notify_message(u, pid, tags, fds);
+ UNIT_VTABLE(u)->notify_message(u, ucred, tags, fds);
else if (_unlikely_(log_get_max_level() >= LOG_DEBUG)) {
_cleanup_free_ char *x = NULL, *y = NULL;
@@ -1777,19 +1784,19 @@ static int manager_dispatch_notify_fd(sd_event_source *source, int fd, uint32_t
* to avoid notifying the same one multiple times. */
u1 = manager_get_unit_by_pid(m, ucred->pid);
if (u1) {
- manager_invoke_notify_message(m, u1, ucred->pid, buf, fds);
+ manager_invoke_notify_message(m, u1, ucred, buf, fds);
found = true;
}
u2 = hashmap_get(m->watch_pids1, LONG_TO_PTR(ucred->pid));
if (u2 && u2 != u1) {
- manager_invoke_notify_message(m, u2, ucred->pid, buf, fds);
+ manager_invoke_notify_message(m, u2, ucred, buf, fds);
found = true;
}
u3 = hashmap_get(m->watch_pids2, LONG_TO_PTR(ucred->pid));
if (u3 && u3 != u2 && u3 != u1) {
- manager_invoke_notify_message(m, u3, ucred->pid, buf, fds);
+ manager_invoke_notify_message(m, u3, ucred, buf, fds);
found = true;
}
diff --git a/src/core/service.c b/src/core/service.c
index fe6e2ff17c..06b39e3a5a 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -700,9 +700,45 @@ static void service_dump(Unit *u, FILE *f, const char *prefix) {
}
}
+static int service_is_suitable_main_pid(Service *s, pid_t pid, int prio) {
+ Unit *owner;
+
+ assert(s);
+ assert(pid > 0);
+
+ /* Checks whether the specified PID is suitable as main PID for this service. returns negative if not, 0 if the
+ * PID is questionnable but should be accepted if the source of configuration is trusted. > 0 if the PID is
+ * good */
+
+ if (pid == getpid() || pid == 1) {
+ log_unit_full(UNIT(s)->id, prio, "New main PID "PID_FMT" is the manager, refusing.", pid);
+ return -EPERM;
+ }
+
+ if (pid == s->control_pid) {
+ log_unit_full(UNIT(s)->id, prio, "New main PID "PID_FMT" is the control process, refusing.", pid);
+ return -EPERM;
+ }
+
+ if (!pid_is_alive(pid)) {
+ log_unit_full(UNIT(s)->id, prio, "New main PID "PID_FMT" does not exist or is a zombie.", pid);
+ return -ESRCH;
+ }
+
+ owner = manager_get_unit_by_pid(UNIT(s)->manager, pid);
+ if (owner == UNIT(s)) {
+ log_unit_debug(UNIT(s)->id, "New main PID "PID_FMT" belongs to service, we are happy.", pid);
+ return 1; /* Yay, it's definitely a good PID */
+ }
+
+ return 0; /* Hmm it's a suspicious PID, let's accept it if configuration source is trusted */
+}
+
static int service_load_pid_file(Service *s, bool may_warn) {
+ char procfs[sizeof("/proc/self/fd/") - 1 + DECIMAL_STR_MAX(int)];
_cleanup_free_ char *k = NULL;
- int r;
+ _cleanup_close_ int fd = -1;
+ int r, prio;
pid_t pid;
assert(s);
@@ -710,30 +746,47 @@ static int service_load_pid_file(Service *s, bool may_warn) {
if (!s->pid_file)
return -ENOENT;
- r = read_one_line_file(s->pid_file, &k);
- if (r < 0) {
- if (may_warn)
- log_unit_info(UNIT(s)->id, "PID file %s not readable (yet?) after %s.", s->pid_file, service_state_to_string(s->state));
- return r;
- }
+ prio = may_warn ? LOG_INFO : LOG_DEBUG;
+
+ fd = chase_symlinks(s->pid_file, NULL, CHASE_OPEN|CHASE_SAFE, NULL);
+ if (fd == -EPERM)
+ return log_unit_full(UNIT(s)->id, prio, "Permission denied while opening PID file or unsafe symlink chain: %s", s->pid_file);
+ if (fd < 0)
+ return log_unit_full(UNIT(s)->id, prio, "Can't open PID file %s (yet?) after %s: %m", s->pid_file, service_state_to_string(s->state));
+
+ /* Let's read the PID file now that we chased it down. But we need to convert the O_PATH fd chase_symlinks() returned us into a proper fd first. */
+ xsprintf(procfs, "/proc/self/fd/%i", fd);
+ r = read_one_line_file(procfs, &k);
+ if (r < 0)
+ return log_unit_error_errno(UNIT(s)->id, r, "Can't convert PID files %s O_PATH file descriptor to proper file descriptor: %m", s->pid_file);
r = parse_pid(k, &pid);
- if (r < 0) {
- if (may_warn)
- log_unit_info_errno(UNIT(s)->id, r, "Failed to read PID from file %s: %m", s->pid_file);
+ if (r < 0)
+ return log_unit_full(UNIT(s)->id, prio, "Failed to parse PID from file %s: %m", s->pid_file);
+
+ if (s->main_pid_known && pid == s->main_pid)
+ return 0;
+
+ r = service_is_suitable_main_pid(s, pid, prio);
+ if (r < 0)
return r;
- }
+ if (r == 0) {
+ struct stat st;
- if (!pid_is_alive(pid)) {
- if (may_warn)
- log_unit_info(UNIT(s)->id, "PID "PID_FMT" read from file %s does not exist or is a zombie.", pid, s->pid_file);
- return -ESRCH;
+ /* Hmm, it's not clear if the new main PID is safe. Let's allow this if the PID file is owned by root */
+
+ if (fstat(fd, &st) < 0)
+ return log_unit_error_errno(UNIT(s)->id, errno, "Failed to fstat() PID file O_PATH fd: %m");
+
+ if (st.st_uid != 0) {
+ log_unit_error(UNIT(s)->id, "New main PID "PID_FMT" does not belong to service, and PID file is not owned by root. Refusing.", pid);
+ return -EPERM;
+ }
+
+ log_unit_debug(UNIT(s)->id, "New main PID "PID_FMT" does not belong to service, but we'll accept it since PID file is owned by root.", pid);
}
if (s->main_pid_known) {
- if (pid == s->main_pid)
- return 0;
-
log_unit_debug(UNIT(s)->id, "Main PID changing: "PID_FMT" -> "PID_FMT, s->main_pid, pid);
service_unwatch_main_pid(s);
@@ -752,7 +805,7 @@ static int service_load_pid_file(Service *s, bool may_warn) {
return r;
}
- return 0;
+ return 1;
}
static int service_search_main_pid(Service *s) {
@@ -2584,7 +2637,7 @@ static void service_sigchld_event(Unit *u, pid_t pid, int code, int status) {
/* Forking services may occasionally move to a new PID.
* As long as they update the PID file before exiting the old
* PID, they're fine. */
- if (service_load_pid_file(s, false) == 0)
+ if (service_load_pid_file(s, false) > 0)
return;
s->main_pid = 0;
@@ -2957,42 +3010,73 @@ static int service_dispatch_watchdog(sd_event_source *source, usec_t usec, void
return 0;
}
-static void service_notify_message(Unit *u, pid_t pid, char **tags, FDSet *fds) {
+static bool service_notify_message_authorized(Service *s, pid_t pid, char **tags, FDSet *fds) {
+ assert(s);
+
+ if (s->notify_access == NOTIFY_NONE) {
+ log_unit_warning(UNIT(s)->id, "Got notification message from PID "PID_FMT", but reception is disabled.", pid);
+ return false;
+ }
+
+ if (s->notify_access == NOTIFY_MAIN && pid != s->main_pid) {
+ if (s->main_pid != 0)
+ log_unit_warning(UNIT(s)->id, "Got notification message from PID "PID_FMT", but reception only permitted for main PID "PID_FMT, pid, s->main_pid);
+ else
+ log_unit_warning(UNIT(s)->id, "Got notification message from PID "PID_FMT", but reception only permitted for main PID which is currently not known", pid);
+
+ return false;
+ }
+
+ return true;
+}
+
+static void service_notify_message(
+ Unit *u,
+ const struct ucred *ucred,
+ char **tags,
+ FDSet *fds) {
Service *s = SERVICE(u);
- _cleanup_free_ char *cc = NULL;
bool notify_dbus = false;
const char *e;
+ int r;
assert(u);
+ assert(ucred);
- cc = strv_join(tags, ", ");
- log_unit_debug(u->id, "%s: Got notification message from PID "PID_FMT" (%s)",
- u->id, pid, isempty(cc) ? "n/a" : cc);
+ if (!service_notify_message_authorized(SERVICE(u), ucred->pid, tags, fds))
+ return;
if (s->notify_access == NOTIFY_NONE) {
- log_unit_warning(u->id, "%s: Got notification message from PID "PID_FMT", but reception is disabled.", u->id, pid);
- return;
- }
+ _cleanup_free_ char *cc = NULL;
- if (s->notify_access == NOTIFY_MAIN && pid != s->main_pid) {
- if (s->main_pid != 0)
- log_unit_warning(u->id, "%s: Got notification message from PID "PID_FMT", but reception only permitted for main PID "PID_FMT, u->id, pid, s->main_pid);
- else
- log_unit_debug(u->id, "%s: Got notification message from PID "PID_FMT", but reception only permitted for main PID which is currently not known", u->id, pid);
- return;
+ cc = strv_join(tags, ", ");
+ log_unit_debug(u->id, "Got notification message from PID "PID_FMT" (%s)", ucred->pid, isempty(cc) ? "n/a" : cc);
}
/* Interpret MAINPID= */
e = strv_find_startswith(tags, "MAINPID=");
if (e && IN_SET(s->state, SERVICE_START, SERVICE_START_POST, SERVICE_RUNNING, SERVICE_RELOAD)) {
- if (parse_pid(e, &pid) < 0)
- log_unit_warning(u->id, "Failed to parse MAINPID= field in notification message: %s", e);
- else {
- log_unit_debug(u->id, "%s: got MAINPID=%s", u->id, e);
+ pid_t new_main_pid;
- service_set_main_pid(s, pid);
- unit_watch_pid(UNIT(s), pid);
- notify_dbus = true;
+ if (parse_pid(e, &new_main_pid) < 0)
+ log_unit_warning(u->id, "Failed to parse MAINPID= field in notification message, ignoring: %s", e);
+ else if (!s->main_pid_known || new_main_pid != s->main_pid) {
+
+ r = service_is_suitable_main_pid(s, new_main_pid, LOG_WARNING);
+ if (r == 0) {
+ /* The new main PID is a bit suspicous, which is OK if the sender is privileged. */
+
+ if (ucred->uid == 0) {
+ log_unit_debug(u->id, "New main PID "PID_FMT" does not belong to service, but we'll accept it as the request to change it came from a privileged process.", new_main_pid);
+ r = 1;
+ } else
+ log_unit_debug(u->id, "New main PID "PID_FMT" does not belong to service, refusing.", new_main_pid);
+ }
+ if (r > 0) {
+ service_set_main_pid(s, new_main_pid);
+ unit_watch_pid(UNIT(s), new_main_pid);
+ notify_dbus = true;
+ }
}
}
diff --git a/src/core/unit.h b/src/core/unit.h
index dfec9cea01..091ef7596e 100644
--- a/src/core/unit.h
+++ b/src/core/unit.h
@@ -376,7 +376,7 @@ struct UnitVTable {
void (*notify_cgroup_empty)(Unit *u);
/* Called whenever a process of this unit sends us a message */
- void (*notify_message)(Unit *u, pid_t pid, char **tags, FDSet *fds);
+ void (*notify_message)(Unit *u, const struct ucred *ucred, char **tags, FDSet *fds);
/* Called whenever a name this Unit registered for comes or
* goes away. */
diff --git a/test/TEST-20-MAINPIDGAMES/Makefile b/test/TEST-20-MAINPIDGAMES/Makefile
new file mode 120000
index 0000000000..e9f93b1104
--- /dev/null
+++ b/test/TEST-20-MAINPIDGAMES/Makefile
@@ -0,0 +1 @@
+../TEST-01-BASIC/Makefile
\ No newline at end of file
diff --git a/test/TEST-20-MAINPIDGAMES/test.sh b/test/TEST-20-MAINPIDGAMES/test.sh
new file mode 100755
index 0000000000..733532b718
--- /dev/null
+++ b/test/TEST-20-MAINPIDGAMES/test.sh
@@ -0,0 +1,81 @@
+#!/bin/bash
+# -*- mode: shell-script; indent-tabs-mode: nil; sh-basic-offset: 4; -*-
+# ex: ts=8 sw=4 sts=4 et filetype=sh
+TEST_DESCRIPTION="test changing main PID"
+
+. $TEST_BASE_DIR/test-functions
+
+check_result_qemu() {
+ ret=1
+ mkdir -p $TESTDIR/root
+ mount ${LOOPDEV}p1 $TESTDIR/root
+ [[ -e $TESTDIR/root/testok ]] && ret=0
+ [[ -f $TESTDIR/root/failed ]] && cp -a $TESTDIR/root/failed $TESTDIR
+ [[ -f $TESTDIR/root/var/log/journal ]] && cp -a $TESTDIR/root/var/log/journal $TESTDIR
+ umount $TESTDIR/root
+ [[ -f $TESTDIR/failed ]] && cat $TESTDIR/failed
+ ls -l $TESTDIR/journal/*/*.journal
+ test -s $TESTDIR/failed && ret=$(($ret+1))
+ return $ret
+}
+
+test_run() {
+ if run_qemu; then
+ check_result_qemu || return 1
+ else
+ dwarn "can't run QEMU, skipping"
+ fi
+ if check_nspawn; then
+ run_nspawn
+ check_result_nspawn || return 1
+ else
+ dwarn "can't run systemd-nspawn, skipping"
+ fi
+ return 0
+}
+
+test_setup() {
+ create_empty_image
+ mkdir -p $TESTDIR/root
+ mount ${LOOPDEV}p1 $TESTDIR/root
+
+ (
+ LOG_LEVEL=5
+ eval $(udevadm info --export --query=env --name=${LOOPDEV}p2)
+
+ setup_basic_environment
+ inst_binary cut
+ inst_binary useradd
+ inst /etc/login.defs
+
+ # setup the testsuite service
+ cat >$initdir/etc/systemd/system/testsuite.service <<EOF
+[Unit]
+Description=Testsuite service
+
+[Service]
+ExecStart=/bin/bash -x /testsuite.sh
+Type=oneshot
+StandardOutput=tty
+StandardError=tty
+NotifyAccess=all
+EOF
+ cp testsuite.sh $initdir/
+
+ useradd -R $initdir -U -u 1234 test
+
+ setup_testsuite
+ )
+ setup_nspawn_root
+
+ ddebug "umount $TESTDIR/root"
+ umount $TESTDIR/root
+}
+
+test_cleanup() {
+ umount $TESTDIR/root 2>/dev/null
+ [[ $LOOPDEV ]] && losetup -d $LOOPDEV
+ return 0
+}
+
+do_test "$@"
diff --git a/test/TEST-20-MAINPIDGAMES/testsuite.sh b/test/TEST-20-MAINPIDGAMES/testsuite.sh
new file mode 100755
index 0000000000..d4ad63865c
--- /dev/null
+++ b/test/TEST-20-MAINPIDGAMES/testsuite.sh
@@ -0,0 +1,189 @@
+#!/bin/bash
+# -*- mode: shell-script; indent-tabs-mode: nil; sh-basic-offset: 4; -*-
+# ex: ts=8 sw=4 sts=4 et filetype=sh
+set -ex
+set -o pipefail
+
+systemctl_show_value() {
+ systemctl show "$@" | cut -d = -f 2-
+}
+
+systemd-analyze set-log-level debug
+
+test `systemctl_show_value -p MainPID testsuite.service` -eq $$
+
+# Start a test process inside of our own cgroup
+sleep infinity &
+INTERNALPID=$!
+disown
+
+# Start a test process outside of our own cgroup
+systemd-run -p User=test --unit=sleep.service /bin/sleep infinity
+EXTERNALPID=`systemctl_show_value -p MainPID sleep.service`
+
+# Update our own main PID to the external test PID, this should work
+systemd-notify MAINPID=$EXTERNALPID
+test `systemctl_show_value -p MainPID testsuite.service` -eq $EXTERNALPID
+
+# Update our own main PID to the internal test PID, this should work, too
+systemd-notify MAINPID=$INTERNALPID
+test `systemctl_show_value -p MainPID testsuite.service` -eq $INTERNALPID
+
+# Update it back to our own PID, this should also work
+systemd-notify MAINPID=$$
+test `systemctl_show_value -p MainPID testsuite.service` -eq $$
+
+# Try to set it to PID 1, which it should ignore, because that's the manager
+systemd-notify MAINPID=1
+test `systemctl_show_value -p MainPID testsuite.service` -eq $$
+
+# Try to set it to PID 0, which is invalid and should be ignored
+systemd-notify MAINPID=0
+test `systemctl_show_value -p MainPID testsuite.service` -eq $$
+
+# Try to set it to a valid but non-existing PID, which should be ignored. (Note
+# that we set the PID to a value well above any known /proc/sys/kernel/pid_max,
+# which means we can be pretty sure it doesn't exist by coincidence)
+systemd-notify MAINPID=1073741824
+test `systemctl_show_value -p MainPID testsuite.service` -eq $$
+
+# Change it again to the external PID, without priviliges this time. This should be ignored, because the PID is from outside of our cgroup and we lack privileges.
+systemd-notify --uid=1000 MAINPID=$EXTERNALPID
+test `systemctl_show_value -p MainPID testsuite.service` -eq $$
+
+# Change it again to the internal PID, without priviliges this time. This should work, as the process is on our cgroup, and that's enough even if we lack privileges.
+systemd-notify --uid=1000 MAINPID=$INTERNALPID
+test `systemctl_show_value -p MainPID testsuite.service` -eq $INTERNALPID
+
+# Update it back to our own PID, this should also work
+systemd-notify --uid=1000 MAINPID=$$
+test `systemctl_show_value -p MainPID testsuite.service` -eq $$
+
+cat >/tmp/mainpid.sh <<EOF
+#!/bin/bash
+
+set -eux
+set -o pipefail
+
+# Create a number of children, and make one the main one
+sleep infinity &
+disown
+
+sleep infinity &
+MAINPID=\$!
+disown
+
+sleep infinity &
+disown
+
+echo \$MAINPID > /run/mainpidsh/pid
+EOF
+chmod +x /tmp/mainpid.sh
+
+cat > /etc/systemd/system/mainpidsh.service <<EOF
+[Unit]
+Description=MainPID test 1 service
+
+[Service]
+StandardOutput=tty
+StandardError=tty
+Type=forking
+RuntimeDirectory=mainpidsh
+PIDFile=/run/mainpidsh/pid
+ExecStart=/tmp/mainpid.sh
+EOF
+
+systemctl daemon-reload
+systemctl start mainpidsh.service
+test `systemctl_show_value -p MainPID mainpidsh.service` -eq `cat /run/mainpidsh/pid`
+
+cat >/tmp/mainpid2.sh <<EOF
+#!/bin/bash
+
+set -eux
+set -o pipefail
+
+# Create a number of children, and make one the main one
+sleep infinity &
+disown
+
+sleep infinity &
+MAINPID=\$!
+disown
+
+sleep infinity &
+disown
+
+echo \$MAINPID > /run/mainpidsh2/pid
+chown 1001:1001 /run/mainpidsh2/pid
+EOF
+chmod +x /tmp/mainpid2.sh
+
+cat > /etc/systemd/system/mainpidsh2.service <<EOF
+[Unit]
+Description=MainPID test 2 service
+
+[Service]
+StandardOutput=tty
+StandardError=tty
+Type=forking
+RuntimeDirectory=mainpidsh2
+PIDFile=/run/mainpidsh2/pid
+ExecStart=/tmp/mainpid2.sh
+EOF
+
+systemctl daemon-reload
+systemctl start mainpidsh2.service
+test `systemctl_show_value -p MainPID mainpidsh2.service` -eq `cat /run/mainpidsh2/pid`
+
+cat >/dev/shm/mainpid3.sh <<EOF
+#!/bin/bash
+
+set -eux
+set -o pipefail
+
+sleep infinity &
+disown
+
+sleep infinity &
+disown
+
+sleep infinity &
+disown
+
+# Let's try to play games, and link up a privileged PID file
+ln -s ../mainpidsh/pid /run/mainpidsh3/pid
+
+# Quick assertion that the link isn't dead
+test -f /run/mainpidsh3/pid
+EOF
+chmod 755 /dev/shm/mainpid3.sh
+
+cat > /etc/systemd/system/mainpidsh3.service <<EOF
+[Unit]
+Description=MainPID test 3 service
+
+[Service]
+StandardOutput=tty
+StandardError=tty
+Type=forking
+RuntimeDirectory=mainpidsh3
+PIDFile=/run/mainpidsh3/pid
+User=test
+TimeoutStartSec=2s
+ExecStart=/dev/shm/mainpid3.sh
+EOF
+
+systemctl daemon-reload
+systemctl start mainpidsh3.service
+
+# Test that this failed due to timeout, and not some other error
+# test `systemctl_show_value -p Result mainpidsh3.service` = timeout
+# Just check that there is no MainPID => the pid file was ignored
+test `systemctl_show_value -p MainPID mainpidsh3.service` -eq 0
+
+systemd-analyze set-log-level info
+
+echo OK > /testok
+
+exit 0
diff --git a/test/test-functions b/test/test-functions
index 78e725d5b9..e50ce556fd 100644
--- a/test/test-functions
+++ b/test/test-functions
@@ -12,7 +12,7 @@ if ! ROOTLIBDIR=$(pkg-config --variable=systemdutildir systemd); then
ROOTLIBDIR=/usr/lib/systemd
fi
-BASICTOOLS="sh bash setsid loadkeys setfont login sulogin gzip sleep echo mount umount cryptsetup date dmsetup modprobe"
+BASICTOOLS="test sh bash setsid loadkeys setfont login sulogin gzip sleep echo mount umount cryptsetup date dmsetup modprobe chmod chown ln"
DEBUGTOOLS="df free ls stty cat ps ln ip route dmesg dhclient mkdir cp ping dhclient strace less grep id tty touch du sort hostname"
function find_qemu_bin() {