From 50352e586282e99b649cf5c0263cccc59e31f73c Mon Sep 17 00:00:00 2001
From: Hagai Cohen <hagai.co@gmail.com>
Date: Mon, 1 Jun 2026 19:44:26 +0300
Subject: [PATCH] config/actions: fix null derefs in pin dispatcher (#14914)

* hyprtester: add issue14134 regression test

D#14134 reports a pin dispatcher SEGV when a monitor hosting a
pinned floating window is disabled (e.g. lid close on a laptop).
After CMonitor::onDisconnect resets m_activeWorkspace to null,
the CMonitor SP stays alive in m_realMonitors, and the pinned-
window branch of moveWorkspaceToMonitor leaves the window's
m_monitor pointing at the disabled monitor.

The next pin dispatch does null deref inside Config::Actions::pinWindow.

* config/actions: fix null derefs in pin dispatcher

PR #14061 replaced moveToWorkspace(m_activeWorkspace) with
assignToSpace(m_activeWorkspace->m_space) and a separate
layoutTarget() call.

The two new derefs aren't covered by the existing PMONITOR check,
and either one being null crashes the compositor.

In practice, i use pyprland which uses pining function,
and since i am on laptop, sometimes my lid is closed and i have
monitor disabled, this causes null deref when computer goes idle.

    Layout::CWindowTarget::assignToSpace   <- segv
    Config::Actions::pinWindow
    pin
    CDispatcherTranslator::run
    CHyprCtl::getReply

In this fix i've added null checks to avoid crashing
---
 hyprtester/src/tests/main/window.cpp        | 21 +++++++++++++++++++++
 src/config/shared/actions/ConfigActions.cpp | 17 ++++++++++++-----
 2 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/hyprtester/src/tests/main/window.cpp b/hyprtester/src/tests/main/window.cpp
index 0a6b6faae..d5906ac7d 100644
--- a/hyprtester/src/tests/main/window.cpp
+++ b/hyprtester/src/tests/main/window.cpp
@@ -588,6 +588,27 @@ TEST_CASE(issue14038) {
     // this should not crash hyprland. If we are alive, we good.
 }
 
+TEST_CASE(issue14134) {
+    OK(getFromSocket("/output create headless HEADLESS-4"));
+    OK(getFromSocket("/dispatch hl.dsp.focus({ monitor = 'HEADLESS-4' })"));
+
+    if (!spawnKitty("kitty_14134"))
+        FAIL_TEST("Could not spawn kitty");
+
+    OK(getFromSocket("/dispatch hl.dsp.window.float({ action = 'toggle', window = 'class:kitty_14134' })"));
+    OK(getFromSocket("/dispatch hl.dsp.window.pin({ action = 'toggle', window = 'class:kitty_14134' })"));
+
+    OK(getFromSocket("/eval hl.monitor({ output = 'HEADLESS-4', disabled = true })"));
+
+    // will return error, should not be OK.
+    getFromSocket("/dispatch hl.dsp.window.pin({ action = 'toggle', window = 'class:kitty_14134' })");
+
+    OK(getFromSocket("/reload"));
+    Tests::killAllWindows();
+    ASSERT(Tests::windowCount(), 0);
+    OK(getFromSocket("/output remove HEADLESS-4"));
+}
+
 TEST_CASE(specialFloatRecenters) {
     if (!spawnKitty("kitty_special_float_recenter"))
         FAIL_TEST("Could not spawn kitty");
diff --git a/src/config/shared/actions/ConfigActions.cpp b/src/config/shared/actions/ConfigActions.cpp
index 7b007c36b..fe435d3e2 100644
--- a/src/config/shared/actions/ConfigActions.cpp
+++ b/src/config/shared/actions/ConfigActions.cpp
@@ -230,15 +230,22 @@ ActionResult Actions::pinWindow(eTogglableAction action, std::optional<PHLWINDOW
     if (wantPin == window->m_pinned)
         return {};
 
-    window->m_pinned = wantPin;
-    window->updateFullscreenInputState();
-    *window->alpha(Desktop::View::WINDOW_ALPHA_FULLSCREEN) = window->isBlockedByFullscreen() ? 0.F : 1.F;
-
     const auto PMONITOR = window->m_monitor.lock();
     if (!PMONITOR)
         return actionError("Window has no monitor", eActionErrorLevel::WARNING, eActionErrorCode::INVALID_STATE);
 
-    window->layoutTarget()->assignToSpace(PMONITOR->m_activeWorkspace->m_space);
+    if (!PMONITOR->m_activeWorkspace || !PMONITOR->m_activeWorkspace->m_space)
+        return actionError("Monitor has no active workspace", eActionErrorLevel::WARNING, eActionErrorCode::INVALID_STATE);
+
+    const auto LAYOUTTARGET = window->layoutTarget();
+    if (!LAYOUTTARGET)
+        return actionError("Window has no layout target", eActionErrorLevel::WARNING, eActionErrorCode::INVALID_STATE);
+
+    window->m_pinned = wantPin;
+    window->updateFullscreenInputState();
+    *window->alpha(Desktop::View::WINDOW_ALPHA_FULLSCREEN) = window->isBlockedByFullscreen() ? 0.F : 1.F;
+
+    LAYOUTTARGET->assignToSpace(PMONITOR->m_activeWorkspace->m_space);
     window->m_ruleApplicator->propertiesChanged(Desktop::Rule::RULE_PROP_PINNED);
 
     const auto PWORKSPACE = window->m_workspace;