From 7200ad179c18a848656be0ecc8e384ef4d73ed89 Mon Sep 17 00:00:00 2001
From: Marco Allegretti <mightymarco4@gmail.com>
Date: Sat, 14 Feb 2026 16:45:37 +0100
Subject: [PATCH] Harden systemd scope cleanup

Tighten transient unit lifecycle handling in GameCenter.

- Drop stale unit watcher mappings on PropertiesChanged for removed sessions.
- When stopping a monitored launch due to timeout or attach failure, fall back
  to terminating scope PIDs if StopUnit fails unexpectedly.

This reduces leaked scopes and improves robustness in failure paths.
---
 src/gamecenter/gamecenterdaemon.cpp | 57 +++++++++++++++++++++++++++--
 1 file changed, 53 insertions(+), 4 deletions(-)

diff --git a/src/gamecenter/gamecenterdaemon.cpp b/src/gamecenter/gamecenterdaemon.cpp
index b3678dd..5f688d5 100644
--- a/src/gamecenter/gamecenterdaemon.cpp
+++ b/src/gamecenter/gamecenterdaemon.cpp
@@ -833,6 +833,15 @@ void GameCenterDaemon::handleSystemdUnitPropertiesChanged(const QDBusObjectPath
 
     auto sit = m_sessions.find(sessionId);
     if (sit == m_sessions.end()) {
+        unwatchSystemdUnit({}, unitPath);
+
+        for (auto nameIt = m_unitNameToSessionId.begin(); nameIt != m_unitNameToSessionId.end();) {
+            if (nameIt.value() == sessionId) {
+                nameIt = m_unitNameToSessionId.erase(nameIt);
+            } else {
+                ++nameIt;
+            }
+        }
         return;
     }
 
@@ -1570,8 +1579,31 @@ QString GameCenterDaemon::launchMonitored(const QVariantMap &launchSpec, const Q
         QVariantMap finalState = sessionToVariantMap(it.value(), stopping ? QStringLiteral("Stopped") : QStringLiteral("Failed"));
 
         if (!it.value().unitName.isEmpty()) {
-            m_systemd.stopUnit(it.value().unitName);
-            unwatchSystemdUnit(it.value().unitName, it.value().unitPath);
+            const QString unitName = it.value().unitName;
+            const QDBusObjectPath unitPath = it.value().unitPath;
+            const uint mainPid = it.value().mainPid;
+
+            const QDBusReply<QDBusObjectPath> stopReply = m_systemd.stopUnit(unitName);
+            if (!stopReply.isValid() && stopReply.error().name() != QLatin1String("org.freedesktop.systemd1.NoSuchUnit")) {
+                QList<uint> pids;
+                if (!unitPath.path().isEmpty()) {
+                    pids = m_systemd.scopePids(unitPath);
+                }
+                if (pids.isEmpty() && it.value().process && it.value().process->processId() > 0) {
+                    pids = {static_cast<uint>(it.value().process->processId())};
+                }
+                if (pids.isEmpty() && mainPid > 0) {
+                    pids = {mainPid};
+                }
+                if (!pids.isEmpty()) {
+                    terminatePids(pids);
+                    QTimer::singleShot(5000, this, [pids]() {
+                        killPids(pids);
+                    });
+                }
+            }
+
+            unwatchSystemdUnit(unitName, unitPath);
         }
 
         if (it.value().scanner) {
@@ -1643,8 +1675,25 @@ void GameCenterDaemon::attachPidsToSession(const QString &sessionId, const QList
             };
 
             if (!it.value().unitName.isEmpty()) {
-                m_systemd.stopUnit(it.value().unitName);
-                unwatchSystemdUnit(it.value().unitName, it.value().unitPath);
+                const QString staleUnitName = it.value().unitName;
+                const QDBusObjectPath staleUnitPath = it.value().unitPath;
+
+                const QDBusReply<QDBusObjectPath> stopReply = m_systemd.stopUnit(staleUnitName);
+                if (!stopReply.isValid() && stopReply.error().name() != QLatin1String("org.freedesktop.systemd1.NoSuchUnit")) {
+                    QList<uint> stalePids;
+                    if (!staleUnitPath.path().isEmpty()) {
+                        stalePids = m_systemd.scopePids(staleUnitPath);
+                    }
+                    if (stalePids.isEmpty()) {
+                        stalePids = pids;
+                    }
+                    terminatePids(stalePids);
+                    QTimer::singleShot(5000, this, [stalePids]() {
+                        killPids(stalePids);
+                    });
+                }
+
+                unwatchSystemdUnit(staleUnitName, staleUnitPath);
             }
 
             QVariantMap finalState = sessionToVariantMap(it.value(), QStringLiteral("Failed"));