Merge remote-tracking branch 'origin/5.13' into 5.14

 Conflicts:
	src/corelib/serialization/qjson_p.h

Change-Id: I83cea141a4de8b3998478bfded84ca9029f7a2a9

5 files changed, 21 insertions, 11 deletions

diff --git a/src/gui/kernel/qdnd.cpp b/src/gui/kernel/qdnd.cpp
index 5c5f166554..dd541af3b8 100644
--- a/src/gui/kernel/qdnd.cpp
+++ b/src/gui/kernel/qdnd.cpp
@@ -113,11 +113,12 @@ Qt::DropAction QDragManager::drag(QDrag *o)
 
     m_object->d_func()->target = 0;
 
-    QGuiApplicationPrivate::instance()->notifyDragStarted(o);
+    QGuiApplicationPrivate::instance()->notifyDragStarted(m_object.data());
     const Qt::DropAction result = m_platformDrag->drag(m_object);
-    m_object = 0;
-    if (!m_platformDrag->ownsDragObject())
-        o->deleteLater();
+    if (!m_object.isNull() && !m_platformDrag->ownsDragObject())
+        m_object->deleteLater();
+
+    m_object.clear();
     return result;
 }
 
diff --git a/src/gui/kernel/qdnd_p.h b/src/gui/kernel/qdnd_p.h
index b1219c8658..abb30986a5 100644
--- a/src/gui/kernel/qdnd_p.h
+++ b/src/gui/kernel/qdnd_p.h
@@ -101,13 +101,13 @@ public:
     void setCurrentTarget(QObject *target, bool dropped = false);
     QObject *currentTarget() const;
 
-    QDrag *object() const { return m_object; }
+    QPointer<QDrag> object() const { return m_object; }
     QObject *source() const;
 
 private:
     QObject *m_currentDropTarget;
     QPlatformDrag *m_platformDrag;
-    QDrag *m_object;
+    QPointer<QDrag> m_object;
 
     static QDragManager *m_instance;
     Q_DISABLE_COPY_MOVE(QDragManager)
diff --git a/src/gui/kernel/qdrag.cpp b/src/gui/kernel/qdrag.cpp
index dcd0d13d5c..8e2f7be23e 100644
--- a/src/gui/kernel/qdrag.cpp
+++ b/src/gui/kernel/qdrag.cpp
@@ -279,8 +279,11 @@ Qt::DropAction QDrag::exec(Qt::DropActions supportedActions, Qt::DropAction defa
     }
     d->supported_actions = supportedActions;
     d->default_action = transformedDefaultDropAction;
-    d->executed_action = QDragManager::self()->drag(this);
-
+    QPointer<QDrag> self = this;
+    auto executed_action = QDragManager::self()->drag(self.data());
+    if (self.isNull())
+        return Qt::IgnoreAction;
+    d->executed_action = executed_action;
     return d->executed_action;
 }
 
diff --git a/src/plugins/platforms/xcb/qxcbdrag.cpp b/src/plugins/platforms/xcb/qxcbdrag.cpp
index 1ce947165d..3d525598ca 100644
--- a/src/plugins/platforms/xcb/qxcbdrag.cpp
+++ b/src/plugins/platforms/xcb/qxcbdrag.cpp
@@ -354,6 +354,11 @@ bool QXcbDrag::findXdndAwareTarget(const QPoint &globalPos, xcb_window_t *target
 
 void QXcbDrag::move(const QPoint &globalPos, Qt::MouseButtons b, Qt::KeyboardModifiers mods)
 {
+    // currentDrag() might be deleted while 'drag' is progressing
+    if (!currentDrag()) {
+        cancel();
+        return;
+    }
     // The source sends XdndEnter and XdndPosition to the target.
     if (source_sameanswer.contains(globalPos) && source_sameanswer.isValid())
         return;
@@ -1076,7 +1081,8 @@ void QXcbDrag::cancel()
         send_leave();
 
     // remove canceled object
-    currentDrag()->deleteLater();
+    if (currentDrag())
+        currentDrag()->deleteLater();
 
     canceled = true;
 }
diff --git a/src/widgets/dialogs/qcolordialog.cpp b/src/widgets/dialogs/qcolordialog.cpp
index fc00290536..d00a600424 100644
--- a/src/widgets/dialogs/qcolordialog.cpp
+++ b/src/widgets/dialogs/qcolordialog.cpp
@@ -504,7 +504,7 @@ void QWellArray::keyPressEvent(QKeyEvent* e)
 // Event filter to be installed on the dialog while in color-picking mode.
 class QColorPickingEventFilter : public QObject {
 public:
-    explicit QColorPickingEventFilter(QColorDialogPrivate *dp, QObject *parent = 0) : QObject(parent), m_dp(dp) {}
+    explicit QColorPickingEventFilter(QColorDialogPrivate *dp, QObject *parent) : QObject(parent), m_dp(dp) {}
 
     bool eventFilter(QObject *, QEvent *event) override
     {
@@ -1611,7 +1611,7 @@ void QColorDialogPrivate::_q_pickScreenColor()
 {
     Q_Q(QColorDialog);
     if (!colorPickingEventFilter)
-        colorPickingEventFilter = new QColorPickingEventFilter(this);
+        colorPickingEventFilter = new QColorPickingEventFilter(this, q);
     q->installEventFilter(colorPickingEventFilter);
     // If user pushes Escape, the last color before picking will be restored.
     beforeScreenColorPicking = cs->currentColor();