Don't crash with invalid QModelIndex or when QTreeWidgetItem is NULL in mimeData()

Change-Id: I0a9abaa05cf136eadf222d3e7d102930719b84ff
Reviewed-by: David Faure <david.faure@kdab.com>

4 files changed, 41 insertions, 13 deletions

diff --git a/src/gui/itemmodels/qstandarditemmodel.cpp b/src/gui/itemmodels/qstandarditemmodel.cpp
index 44ee710268..eae2b419e3 100644
--- a/src/gui/itemmodels/qstandarditemmodel.cpp
+++ b/src/gui/itemmodels/qstandarditemmodel.cpp
@@ -2942,9 +2942,13 @@ QMimeData *QStandardItemModel::mimeData(const QModelIndexList &indexes) const
     itemsSet.reserve(indexes.count());
     stack.reserve(indexes.count());
     for (int i = 0; i < indexes.count(); ++i) {
-        QStandardItem *item = itemFromIndex(indexes.at(i));
-        itemsSet << item;
-        stack.push(item);
+        if (QStandardItem *item = itemFromIndex(indexes.at(i))) {
+            itemsSet << item;
+            stack.push(item);
+        } else {
+            qWarning() << "QStandardItemModel::mimeData: No item associated with invalid index";
+            return 0;
+        }
     }
 
     //remove duplicates childrens
@@ -2978,16 +2982,11 @@ QMimeData *QStandardItemModel::mimeData(const QModelIndexList &indexes) const
     //stream everything recursively
     while (!stack.isEmpty()) {
         QStandardItem *item = stack.pop();
-        if(itemsSet.contains(item)) { //if the item is selection 'top-level', strem its position
+        if (itemsSet.contains(item)) //if the item is selection 'top-level', stream its position
             stream << item->row() << item->column();
-        }
-        if(item) {
-            stream << *item << item->columnCount() << item->d_ptr->children.count();
-            stack += item->d_ptr->children;
-        } else {
-            QStandardItem dummy;
-            stream << dummy << 0 << 0;
-        }
+
+        stream << *item << item->columnCount() << item->d_ptr->children.count();
+        stack += item->d_ptr->children;
     }
 
     data->setData(format, encoded);
diff --git a/src/widgets/itemviews/qtreewidget.cpp b/src/widgets/itemviews/qtreewidget.cpp
index 7378b9979a..769a5b97b9 100644
--- a/src/widgets/itemviews/qtreewidget.cpp
+++ b/src/widgets/itemviews/qtreewidget.cpp
@@ -3273,8 +3273,18 @@ QMimeData *QTreeWidget::mimeData(const QList<QTreeWidgetItem*> items) const
         QList<QModelIndex> indexes;
         for (int i = 0; i < items.count(); ++i) {
             QTreeWidgetItem *item = items.at(i);
+            if (!item) {
+                qWarning() << "QTreeWidget::mimeData: Null-item passed";
+                return 0;
+            }
+
             for (int c = 0; c < item->values.count(); ++c) {
-                indexes << indexFromItem(item, c);
+                const QModelIndex index = indexFromItem(item, c);
+                if (!index.isValid()) {
+                    qWarning() << "QTreeWidget::mimeData: No index associated with item :" << item;
+                    return 0;
+                }
+                indexes << index;
             }
         }
         return d->model->QAbstractItemModel::mimeData(indexes);
diff --git a/tests/auto/gui/itemmodels/qstandarditemmodel/tst_qstandarditemmodel.cpp b/tests/auto/gui/itemmodels/qstandarditemmodel/tst_qstandarditemmodel.cpp
index cde6141a71..10dedfaf95 100644
--- a/tests/auto/gui/itemmodels/qstandarditemmodel/tst_qstandarditemmodel.cpp
+++ b/tests/auto/gui/itemmodels/qstandarditemmodel/tst_qstandarditemmodel.cpp
@@ -129,6 +129,7 @@ private slots:
     void removeRowsAndColumns();
 
     void itemRoleNames();
+    void getMimeDataWithInvalidModelIndex();
 
 private:
     QAbstractItemModel *m_model;
@@ -1671,6 +1672,13 @@ void tst_QStandardItemModel::itemRoleNames()
     VERIFY_MODEL
 }
 
+void tst_QStandardItemModel::getMimeDataWithInvalidModelIndex()
+{
+    QStandardItemModel model;
+    QTest::ignoreMessage(QtWarningMsg, "QStandardItemModel::mimeData: No item associated with invalid index");
+    QMimeData *data = model.mimeData(QModelIndexList() << QModelIndex());
+    QVERIFY(!data);
+}
 
 QTEST_MAIN(tst_QStandardItemModel)
 #include "tst_qstandarditemmodel.moc"
diff --git a/tests/auto/widgets/itemviews/qtreewidget/tst_qtreewidget.cpp b/tests/auto/widgets/itemviews/qtreewidget/tst_qtreewidget.cpp
index c1331d62e1..bdeaaf38db 100644
--- a/tests/auto/widgets/itemviews/qtreewidget/tst_qtreewidget.cpp
+++ b/tests/auto/widgets/itemviews/qtreewidget/tst_qtreewidget.cpp
@@ -49,6 +49,9 @@ class CustomTreeWidget : public QTreeWidget
 public:
     QModelIndex indexFromItem(QTreeWidgetItem *item, int column = 0) const
     { return QTreeWidget::indexFromItem(item, column); }
+
+    QMimeData * mimeData(const QList<QTreeWidgetItem*> items) const
+    { return QTreeWidget::mimeData(items); }
 };
 
 class tst_QTreeWidget : public QObject
@@ -157,6 +160,7 @@ private slots:
     void setChildIndicatorPolicy();
 
     void task20345_sortChildren();
+    void getMimeDataWithInvalidItem();
 
 public slots:
     void itemSelectionChanged();
@@ -3368,6 +3372,13 @@ void tst_QTreeWidget::task20345_sortChildren()
     QVERIFY(1);
 }
 
+void tst_QTreeWidget::getMimeDataWithInvalidItem()
+{
+    CustomTreeWidget w;
+    QTest::ignoreMessage(QtWarningMsg, "QTreeWidget::mimeData: Null-item passed");
+    QMimeData *md = w.mimeData(QList<QTreeWidgetItem*>() << Q_NULLPTR);
+    QVERIFY(!md);
+}
 
 QTEST_MAIN(tst_QTreeWidget)
 #include "tst_qtreewidget.moc"