core: transition to FINAL_SIGTERM state after ExecStopPost=

Fixes #14566

(cherry picked from commit c1566ef0d22ed786b9ecf4c476e53b8a91e67578)
(cherry picked from commit b7f2308bda4942d1b8e10250db6836fe4fc0d8b8)
(cherry picked from commit 49e7c3b617613306211cc8e28e68d4e5be8fbec4)

5 files changed, 82 insertions, 0 deletions

diff --git a/src/core/service.c b/src/core/service.c
index 98aa9b9292..72b579a32c 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -3492,6 +3492,12 @@ static void service_sigchld_event(Unit *u, pid_t pid, int code, int status) {
                                 break;
 
                         case SERVICE_STOP_POST:
+
+                                if (control_pid_good(s) <= 0)
+                                        service_enter_signal(s, SERVICE_FINAL_SIGTERM, f);
+
+                                break;
+
                         case SERVICE_FINAL_SIGTERM:
                         case SERVICE_FINAL_SIGKILL:
 
@@ -3641,6 +3647,10 @@ static void service_sigchld_event(Unit *u, pid_t pid, int code, int status) {
                                 break;
 
                         case SERVICE_STOP_POST:
+                                if (main_pid_good(s) <= 0)
+                                        service_enter_signal(s, SERVICE_FINAL_SIGTERM, f);
+                                break;
+
                         case SERVICE_FINAL_SIGTERM:
                         case SERVICE_FINAL_SIGKILL:
                                 if (main_pid_good(s) <= 0)
diff --git a/test/TEST-47-ISSUE-14566/Makefile b/test/TEST-47-ISSUE-14566/Makefile
new file mode 120000
index 0000000000..e9f93b1104
--- /dev/null
+++ b/test/TEST-47-ISSUE-14566/Makefile
@@ -0,0 +1 @@
+../TEST-01-BASIC/Makefile
\ No newline at end of file
diff --git a/test/TEST-47-ISSUE-14566/repro.sh b/test/TEST-47-ISSUE-14566/repro.sh
new file mode 100755
index 0000000000..5217602257
--- /dev/null
+++ b/test/TEST-47-ISSUE-14566/repro.sh
@@ -0,0 +1,5 @@
+#!/bin/bash
+
+sleep infinity &
+echo $! > /leakedtestpid
+wait $!
diff --git a/test/TEST-47-ISSUE-14566/test.sh b/test/TEST-47-ISSUE-14566/test.sh
new file mode 100755
index 0000000000..35f862331c
--- /dev/null
+++ b/test/TEST-47-ISSUE-14566/test.sh
@@ -0,0 +1,43 @@
+#!/bin/bash
+set -e
+TEST_DESCRIPTION="Test that KillMode=mixed does not leave left over proccesses with ExecStopPost="
+. $TEST_BASE_DIR/test-functions
+
+test_setup() {
+    create_empty_image_rootdir
+
+    (
+        LOG_LEVEL=5
+        eval $(udevadm info --export --query=env --name=${LOOPDEV}p2)
+
+        setup_basic_environment
+        mask_supporting_services
+
+        # setup the testsuite service
+        cat >$initdir/etc/systemd/system/testsuite.service <<EOF
+[Unit]
+Description=Testsuite service
+
+[Service]
+ExecStart=/testsuite.sh
+Type=oneshot
+EOF
+        cat > $initdir/etc/systemd/system/issue_14566_test.service << EOF
+[Unit]
+Description=Issue 14566 Repro
+
+[Service]
+ExecStart=/repro.sh
+ExecStopPost=/bin/true
+KillMode=mixed
+EOF
+
+        cp testsuite.sh $initdir/
+        cp repro.sh $initdir/
+
+        setup_testsuite
+    )
+    setup_nspawn_root
+}
+
+do_test "$@"
diff --git a/test/TEST-47-ISSUE-14566/testsuite.sh b/test/TEST-47-ISSUE-14566/testsuite.sh
new file mode 100755
index 0000000000..d917cf52ff
--- /dev/null
+++ b/test/TEST-47-ISSUE-14566/testsuite.sh
@@ -0,0 +1,23 @@
+#!/bin/bash
+set -ex
+set -o pipefail
+
+systemd-analyze log-level debug
+systemd-analyze log-target console
+
+systemctl start issue_14566_test
+systemctl status issue_14566_test
+
+leaked_pid=$(cat /leakedtestpid)
+
+systemctl stop issue_14566_test
+
+# Leaked PID will still be around if we're buggy.
+# I personally prefer to see 42.
+ps -p "$leaked_pid" && exit 42
+
+systemd-analyze log-level info
+
+echo OK > /testok
+
+exit 0