path: root/gui-apps/sddm/files/sddm-0.21.0_p20251101-fix-restart-greeter.patch

From 4d06b6f77024d3ecaa458f0474691bf8b5f1306e Mon Sep 17 00:00:00 2001
From: "tsrk." <tsrk@tsrk.me>
Date: Sun, 13 Jul 2025 19:42:40 +0200
Subject: [PATCH 1/9] fix(helper): do not badly exit on SIGHUP

Signed-off-by: tsrk. <tsrk@tsrk.me>
---
 src/helper/HelperApp.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/helper/HelperApp.cpp b/src/helper/HelperApp.cpp
index 32da42df3..49b7e1d79 100644
--- a/src/helper/HelperApp.cpp
+++ b/src/helper/HelperApp.cpp
@@ -53,8 +53,13 @@ namespace SDDM {
             , m_socket(new QLocalSocket(this)) {
         qInstallMessageHandler(HelperMessageHandler);
         SignalHandler *s = new SignalHandler(this);
+        s->addCustomSignal(SIGHUP);
         QObject::connect(s, &SignalHandler::sigtermReceived, m_session, [] {
-            QCoreApplication::instance()->exit(-1);
+            QCoreApplication::instance()->exit(Auth::HELPER_OTHER_ERROR);
+        });
+
+        QObject::connect(s, &SignalHandler::customSignalReceived, m_session, [](int) {
+            QCoreApplication::instance()->exit(Auth::HELPER_OTHER_ERROR);
         });
 
         QTimer::singleShot(0, this, SLOT(setUp()));

From 2eba0aa7e32da2becfb2e48327b7f4e94cdd0275 Mon Sep 17 00:00:00 2001
From: "tsrk." <tsrk@tsrk.me>
Date: Sun, 20 Jul 2025 17:15:54 +0200
Subject: [PATCH 2/9] fix(helper): avoid exiting 1 at all costs when session
 finishes

Signed-off-by: tsrk. <tsrk@tsrk.me>
---
 src/helper/HelperApp.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/helper/HelperApp.cpp b/src/helper/HelperApp.cpp
index 49b7e1d79..7e8cd6d10 100644
--- a/src/helper/HelperApp.cpp
+++ b/src/helper/HelperApp.cpp
@@ -199,7 +199,12 @@ namespace SDDM {
     }
 
     void HelperApp::sessionFinished(int status) {
-        exit(status);
+        if (status != 0) {
+            qWarning("Session crashed (exit code %d).", status);
+            exit(Auth::HELPER_SESSION_ERROR);
+        }
+        else
+            exit(Auth::HELPER_SUCCESS);
     }
 
     void HelperApp::info(const QString& message, Auth::Info type) {

From ff0a330ada7062094fc2360e0432c92063f3ec2d Mon Sep 17 00:00:00 2001
From: "tsrk." <tsrk@tsrk.me>
Date: Tue, 29 Jul 2025 22:18:34 +0200
Subject: [PATCH 3/9] fix(auth): do not cast exit status if `QProcess` is not
 exited normally

A QProcess::CrashExit happen in most cases when a signal killed it. And
returning from a signal-killed process on Linux makes QProcess:finished
return the signal, which is a really bad idea to cast into a random
enum.

Qt also mentions that `exitCode` is only valid for QProcess::NormalExit
invocations

Signed-off-by: tsrk. <tsrk@tsrk.me>
---
 src/auth/Auth.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/auth/Auth.cpp b/src/auth/Auth.cpp
index 6c9b5c6b4..6ff38ef1f 100644
--- a/src/auth/Auth.cpp
+++ b/src/auth/Auth.cpp
@@ -230,7 +230,10 @@ namespace SDDM {
         else
             qWarning("Auth: sddm-helper exited with %d", exitCode);
 
-        Q_EMIT qobject_cast<Auth*>(parent())->finished((Auth::HelperExitStatus)exitCode);
+        if (exitStatus == QProcess::NormalExit)
+            Q_EMIT qobject_cast<Auth*>(parent())->finished((Auth::HelperExitStatus)exitCode);
+        else
+            Q_EMIT qobject_cast<Auth*>(parent())->finished(Auth::HELPER_OTHER_ERROR);
     }
 
     void Auth::Private::childError(QProcess::ProcessError error) {

From 97e918b17a5ebc6cb8629cde3a6bc8b5bf44cacc Mon Sep 17 00:00:00 2001
From: "tsrk." <tsrk@tsrk.me>
Date: Wed, 30 Jul 2025 12:24:17 +0200
Subject: [PATCH 4/9] fix(helper): remove overload of `QProcess::finished` in
 UserSession

This will allow HelperApp to dinstinguish between a crash (most likely
by a signal) from a normal exit.

Signed-off-by: tsrk. <tsrk@tsrk.me>
---
 src/helper/HelperApp.cpp   | 12 ++++++++----
 src/helper/HelperApp.h     |  2 +-
 src/helper/UserSession.cpp |  3 +--
 src/helper/UserSession.h   |  4 ----
 4 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/src/helper/HelperApp.cpp b/src/helper/HelperApp.cpp
index 7e8cd6d10..e0141bb7c 100644
--- a/src/helper/HelperApp.cpp
+++ b/src/helper/HelperApp.cpp
@@ -131,7 +131,7 @@ namespace SDDM {
         }
 
         connect(m_socket, &QLocalSocket::connected, this, &HelperApp::doAuth);
-        connect(m_session, &UserSession::finished, this, &HelperApp::sessionFinished);
+        connect(m_session, QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished), this, &HelperApp::sessionFinished);
         m_socket->connectToServer(server, QIODevice::ReadWrite | QIODevice::Unbuffered);
     }
 
@@ -198,9 +198,13 @@ namespace SDDM {
         return;
     }
 
-    void HelperApp::sessionFinished(int status) {
-        if (status != 0) {
-            qWarning("Session crashed (exit code %d).", status);
+    void HelperApp::sessionFinished(int exitCode, QProcess::ExitStatus exitStatus) {
+        if (exitStatus == QProcess::CrashExit) {
+            qWarning("Session crashed (killed by signal %d).", exitCode);
+            exit(Auth::HELPER_SESSION_ERROR);
+        }
+        else if (exitCode != 0) {
+            qWarning("Session crashed (exit code %d).", exitCode);
             exit(Auth::HELPER_SESSION_ERROR);
         }
         else
diff --git a/src/helper/HelperApp.h b/src/helper/HelperApp.h
index 64ea0e1c8..9874ab8eb 100644
--- a/src/helper/HelperApp.h
+++ b/src/helper/HelperApp.h
@@ -54,7 +54,7 @@ namespace SDDM {
         void setUp();
         void doAuth();
 
-        void sessionFinished(int status);
+        void sessionFinished(int exitCode, QProcess::ExitStatus exitStatus);
 
     private:
         qint64 m_id { -1 };
diff --git a/src/helper/UserSession.cpp b/src/helper/UserSession.cpp
index 03fd396ee..5fd378a6e 100644
--- a/src/helper/UserSession.cpp
+++ b/src/helper/UserSession.cpp
@@ -47,7 +47,6 @@ namespace SDDM {
     UserSession::UserSession(HelperApp *parent)
         : QProcess(parent)
     {
-        connect(this, QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished), this, &UserSession::finished);
 #if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
         setChildProcessModifier(std::bind(&UserSession::childModifier, this));
 #endif
@@ -157,7 +156,7 @@ namespace SDDM {
                 }
             }
         } else {
-            Q_EMIT finished(Auth::HELPER_OTHER_ERROR);
+            Q_EMIT finished(Auth::HELPER_OTHER_ERROR, QProcess::NormalExit);
         }
     }
 
diff --git a/src/helper/UserSession.h b/src/helper/UserSession.h
index ecaef8679..78cd994a7 100644
--- a/src/helper/UserSession.h
+++ b/src/helper/UserSession.h
@@ -51,10 +51,6 @@ namespace SDDM {
         */
         qint64 cachedProcessId();
 
-
-    Q_SIGNALS:
-        void finished(int exitCode);
-
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
     protected:
         void setupChildProcess() override;

From 7052ba863174faa05fed8cbbdc7c71cf202e6cfd Mon Sep 17 00:00:00 2001
From: "tsrk." <tsrk@tsrk.me>
Date: Wed, 30 Jul 2025 13:37:14 +0200
Subject: [PATCH 5/9] style(helper): rearrange if conditions to explicitly
 check for normal exit

Signed-off-by: tsrk. <tsrk@tsrk.me>
---
 src/helper/HelperApp.cpp | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/src/helper/HelperApp.cpp b/src/helper/HelperApp.cpp
index e0141bb7c..fa1167c9f 100644
--- a/src/helper/HelperApp.cpp
+++ b/src/helper/HelperApp.cpp
@@ -199,16 +199,16 @@ namespace SDDM {
     }
 
     void HelperApp::sessionFinished(int exitCode, QProcess::ExitStatus exitStatus) {
-        if (exitStatus == QProcess::CrashExit) {
-            qWarning("Session crashed (killed by signal %d).", exitCode);
-            exit(Auth::HELPER_SESSION_ERROR);
-        }
-        else if (exitCode != 0) {
-            qWarning("Session crashed (exit code %d).", exitCode);
-            exit(Auth::HELPER_SESSION_ERROR);
+        if (exitStatus == QProcess::NormalExit) {
+            if (exitCode != 0) {
+                qWarning("Session crashed (exit code %d).", exitCode);
+                exit(Auth::HELPER_SESSION_ERROR);
+            }
+            else
+                exit(Auth::HELPER_SUCCESS);
         }
-        else
-            exit(Auth::HELPER_SUCCESS);
+        qWarning("Session crashed (killed by signal %d).", exitCode);
+        exit(Auth::HELPER_SESSION_ERROR);
     }
 
     void HelperApp::info(const QString& message, Auth::Info type) {

From f886081f98f02ed42e517be6949e1a22971b3e1e Mon Sep 17 00:00:00 2001
From: "tsrk." <tsrk@tsrk.me>
Date: Fri, 1 Aug 2025 01:26:48 +0200
Subject: [PATCH 6/9] fix(helper): return after exits and check for session
 state in destructor

This avoids calling exit an unnecessary number of times, which can
potentially falsify the real return code, and cause restrat loops

Signed-off-by: tsrk. <tsrk@tsrk.me>
---
 src/helper/HelperApp.cpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/helper/HelperApp.cpp b/src/helper/HelperApp.cpp
index fa1167c9f..6a39ac00b 100644
--- a/src/helper/HelperApp.cpp
+++ b/src/helper/HelperApp.cpp
@@ -206,7 +206,11 @@ namespace SDDM {
             }
             else
                 exit(Auth::HELPER_SUCCESS);
+            return;
         }
+
+        Q_ASSERT_X(exitCode != 0, "HelperApp::sessionFinished", "Crashing with 0 is impossible");
+
         qWarning("Session crashed (killed by signal %d).", exitCode);
         exit(Auth::HELPER_SESSION_ERROR);
     }
@@ -298,7 +302,9 @@ namespace SDDM {
     HelperApp::~HelperApp() {
         Q_ASSERT(getuid() == 0);
 
-        m_session->stop();
+        // Avoid re-emitting QProcess::finished if session is not running
+        if (m_session->state() != QProcess::NotRunning)
+            m_session->stop();
         m_backend->closeSession();
 
         // write logout to utmp/wtmp

From 72db1388b931858af3d0f066ed5c3a1948979422 Mon Sep 17 00:00:00 2001
From: "tsrk." <tsrk@tsrk.me>
Date: Fri, 1 Aug 2025 11:42:46 +0200
Subject: [PATCH 7/9] fix(helper): do not emit finish when stopping already
 stopped session

Signed-off-by: tsrk. <tsrk@tsrk.me>
---
 src/helper/UserSession.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/helper/UserSession.cpp b/src/helper/UserSession.cpp
index 5fd378a6e..3e0a5afb4 100644
--- a/src/helper/UserSession.cpp
+++ b/src/helper/UserSession.cpp
@@ -156,7 +156,7 @@ namespace SDDM {
                 }
             }
         } else {
-            Q_EMIT finished(Auth::HELPER_OTHER_ERROR, QProcess::NormalExit);
+            qInfo() << "Attempted to stop session, but was already not running";
         }
     }
 

From 7aa2576b1a916796b1700a426bd9df1b368007b7 Mon Sep 17 00:00:00 2001
From: "tsrk." <tsrk@tsrk.me>
Date: Fri, 1 Aug 2025 11:43:58 +0200
Subject: [PATCH 8/9] style(helper): explicit usage of `QCoreApplication::exit`

Signed-off-by: tsrk. <tsrk@tsrk.me>
---
 src/helper/HelperApp.cpp | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/src/helper/HelperApp.cpp b/src/helper/HelperApp.cpp
index 6a39ac00b..f7958e9be 100644
--- a/src/helper/HelperApp.cpp
+++ b/src/helper/HelperApp.cpp
@@ -73,7 +73,7 @@ namespace SDDM {
         if ((pos = args.indexOf(QStringLiteral("--socket"))) >= 0) {
             if (pos >= args.length() - 1) {
                 qCritical() << "This application is not supposed to be executed manually";
-                exit(Auth::HELPER_OTHER_ERROR);
+                QCoreApplication::exit(Auth::HELPER_OTHER_ERROR);
                 return;
             }
             server = args[pos + 1];
@@ -82,7 +82,7 @@ namespace SDDM {
         if ((pos = args.indexOf(QStringLiteral("--id"))) >= 0) {
             if (pos >= args.length() - 1) {
                 qCritical() << "This application is not supposed to be executed manually";
-                exit(Auth::HELPER_OTHER_ERROR);
+                QCoreApplication::exit(Auth::HELPER_OTHER_ERROR);
                 return;
             }
             m_id = QString(args[pos + 1]).toLongLong();
@@ -91,7 +91,7 @@ namespace SDDM {
         if ((pos = args.indexOf(QStringLiteral("--start"))) >= 0) {
             if (pos >= args.length() - 1) {
                 qCritical() << "This application is not supposed to be executed manually";
-                exit(Auth::HELPER_OTHER_ERROR);
+                QCoreApplication::exit(Auth::HELPER_OTHER_ERROR);
                 return;
             }
             m_session->setPath(args[pos + 1]);
@@ -100,7 +100,7 @@ namespace SDDM {
         if ((pos = args.indexOf(QStringLiteral("--user"))) >= 0) {
             if (pos >= args.length() - 1) {
                 qCritical() << "This application is not supposed to be executed manually";
-                exit(Auth::HELPER_OTHER_ERROR);
+                QCoreApplication::exit(Auth::HELPER_OTHER_ERROR);
                 return;
             }
             m_user = args[pos + 1];
@@ -109,7 +109,7 @@ namespace SDDM {
         if ((pos = args.indexOf(QStringLiteral("--display-server"))) >= 0) {
             if (pos >= args.length() - 1) {
                 qCritical() << "This application is not supposed to be executed manually";
-                exit(Auth::HELPER_OTHER_ERROR);
+                QCoreApplication::exit(Auth::HELPER_OTHER_ERROR);
                 return;
             }
             m_session->setDisplayServerCommand(args[pos + 1]);
@@ -126,7 +126,7 @@ namespace SDDM {
 
         if (server.isEmpty() || m_id <= 0) {
             qCritical() << "This application is not supposed to be executed manually";
-            exit(Auth::HELPER_OTHER_ERROR);
+            QCoreApplication::exit(Auth::HELPER_OTHER_ERROR);
             return;
         }
 
@@ -151,7 +151,7 @@ namespace SDDM {
             const QString vt = env.value(QStringLiteral("XDG_VTNR"));
             utmpLogin(vt, displayId, m_user, 0, false);
 
-            exit(Auth::HELPER_AUTH_ERROR);
+            QCoreApplication::exit(Auth::HELPER_AUTH_ERROR);
             return;
         }
 
@@ -165,7 +165,7 @@ namespace SDDM {
             const QString vt = env.value(QStringLiteral("XDG_VTNR"));
             utmpLogin(vt, displayId, m_user, 0, false);
 
-            exit(Auth::HELPER_AUTH_ERROR);
+            QCoreApplication::exit(Auth::HELPER_AUTH_ERROR);
             return;
         }
 
@@ -178,7 +178,7 @@ namespace SDDM {
 
             if (!m_backend->openSession()) {
                 sessionOpened(false);
-                exit(Auth::HELPER_SESSION_ERROR);
+                QCoreApplication::exit(Auth::HELPER_SESSION_ERROR);
                 return;
             }
 
@@ -194,7 +194,7 @@ namespace SDDM {
             }
         }
         else
-            exit(Auth::HELPER_SUCCESS);
+            QCoreApplication::exit(Auth::HELPER_SUCCESS);
         return;
     }
 
@@ -202,17 +202,17 @@ namespace SDDM {
         if (exitStatus == QProcess::NormalExit) {
             if (exitCode != 0) {
                 qWarning("Session crashed (exit code %d).", exitCode);
-                exit(Auth::HELPER_SESSION_ERROR);
+                QCoreApplication::exit(Auth::HELPER_SESSION_ERROR);
             }
             else
-                exit(Auth::HELPER_SUCCESS);
+                QCoreApplication::exit(Auth::HELPER_SUCCESS);
             return;
         }
 
         Q_ASSERT_X(exitCode != 0, "HelperApp::sessionFinished", "Crashing with 0 is impossible");
 
         qWarning("Session crashed (killed by signal %d).", exitCode);
-        exit(Auth::HELPER_SESSION_ERROR);
+        QCoreApplication::exit(Auth::HELPER_SESSION_ERROR);
     }
 
     void HelperApp::info(const QString& message, Auth::Info type) {

From 4978251750021d5686f5837dffd12a5e99b7ada6 Mon Sep 17 00:00:00 2001
From: "tsrk." <tsrk@tsrk.me>
Date: Fri, 1 Aug 2025 12:13:12 +0200
Subject: [PATCH 9/9] fix(helper): disconnect `sessionFinished` when exiting

Calling `UserSession::stop` results in a call to `QProcess::terminate`,
which sends a SIGTERM to the session. `QProcess` will catch that and
emit an excess `QProcess::finished(15, 1)` which we don't want to handle
since we are in the process of exiting.

Signed-off-by: tsrk. <tsrk@tsrk.me>
---
 src/helper/HelperApp.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/helper/HelperApp.cpp b/src/helper/HelperApp.cpp
index f7958e9be..744a4ef01 100644
--- a/src/helper/HelperApp.cpp
+++ b/src/helper/HelperApp.cpp
@@ -302,7 +302,8 @@ namespace SDDM {
     HelperApp::~HelperApp() {
         Q_ASSERT(getuid() == 0);
 
-        // Avoid re-emitting QProcess::finished if session is not running
+        // Avoid calls to sessionFinished when exiting
+        disconnect(m_session, QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished), this, &HelperApp::sessionFinished);
         if (m_session->state() != QProcess::NotRunning)
             m_session->stop();
         m_backend->closeSession();