Prevent crash in OpenGL engine when scaling images / pixmaps.

Make sure the resulting image / pixmap is valid if the source was valid.

Task-number: QTBUG-19157
Reviewed-by: Kim
Reviewed-by: Benjamin Poulain
(cherry picked from commit 1c5da7207a21cc44a4a08d291c290ffcd9b958fd)

4 files changed, 20 insertions, 0 deletions

diff --git a/src/gui/image/qimage.cpp b/src/gui/image/qimage.cpp
index 50b372ea63..25f6295b71 100644
--- a/src/gui/image/qimage.cpp
+++ b/src/gui/image/qimage.cpp
@@ -4449,6 +4449,8 @@ QImage QImage::scaled(const QSize& s, Qt::AspectRatioMode aspectMode, Qt::Transf
 
     QSize newSize = size();
     newSize.scale(s, aspectMode);
+    newSize.rwidth() = qMax(newSize.width(), 1);
+    newSize.rheight() = qMax(newSize.height(), 1);
     if (newSize == size())
         return *this;
 
diff --git a/src/gui/image/qpixmap.cpp b/src/gui/image/qpixmap.cpp
index c34f6ac1b2..640864d7dc 100644
--- a/src/gui/image/qpixmap.cpp
+++ b/src/gui/image/qpixmap.cpp
@@ -1514,6 +1514,8 @@ QPixmap QPixmap::scaled(const QSize& s, Qt::AspectRatioMode aspectMode, Qt::Tran
 
     QSize newSize = size();
     newSize.scale(s, aspectMode);
+    newSize.rwidth() = qMax(newSize.width(), 1);
+    newSize.rheight() = qMax(newSize.height(), 1);
     if (newSize == size())
         return *this;
 
diff --git a/tests/auto/qimage/tst_qimage.cpp b/tests/auto/qimage/tst_qimage.cpp
index c5ded0d158..ad85bf5cce 100644
--- a/tests/auto/qimage/tst_qimage.cpp
+++ b/tests/auto/qimage/tst_qimage.cpp
@@ -151,6 +151,7 @@ private slots:
     void rgbSwapped();
 
     void deepCopyWhenPaintingActive();
+    void scaled_QTBUG19157();
 };
 
 tst_QImage::tst_QImage()
@@ -2029,5 +2030,12 @@ void tst_QImage::deepCopyWhenPaintingActive()
     QVERIFY(copy != image);
 }
 
+void tst_QImage::scaled_QTBUG19157()
+{
+    QImage foo(5000, 1, QImage::Format_RGB32);
+    foo = foo.scaled(1024, 1024, Qt::KeepAspectRatio);
+    QVERIFY(!foo.isNull());
+}
+
 QTEST_MAIN(tst_QImage)
 #include "tst_qimage.moc"
diff --git a/tests/auto/qpixmap/tst_qpixmap.cpp b/tests/auto/qpixmap/tst_qpixmap.cpp
index 4ba51de7e5..1f1ee88b23 100644
--- a/tests/auto/qpixmap/tst_qpixmap.cpp
+++ b/tests/auto/qpixmap/tst_qpixmap.cpp
@@ -196,6 +196,7 @@ private slots:
 #if defined(Q_OS_SYMBIAN) && !defined(QT_NO_OPENVG)
     void vgImageReadBack();
 #endif
+    void scaled_QTBUG19157();
 };
 
 static bool lenientCompare(const QPixmap &actual, const QPixmap &expected)
@@ -1897,5 +1898,12 @@ void tst_QPixmap::vgImageReadBack()
 }
 #endif // Symbian & OpenVG
 
+void tst_QPixmap::scaled_QTBUG19157()
+{
+    QPixmap foo(5000, 1);
+    foo = foo.scaled(1024, 1024, Qt::KeepAspectRatio);
+    QVERIFY(!foo.isNull());
+}
+
 QTEST_MAIN(tst_QPixmap)
 #include "tst_qpixmap.moc"