Merge remote-tracking branch 'origin/5.6.0' into 5.6

Change-Id: I0b190005377a23a91da3563428e223b8a3b18333

2 files changed, 7 insertions, 1 deletions

diff --git a/src/gui/image/qbmphandler.cpp b/src/gui/image/qbmphandler.cpp
index ef12b23caa..27bab10196 100644
--- a/src/gui/image/qbmphandler.cpp
+++ b/src/gui/image/qbmphandler.cpp
@@ -294,7 +294,7 @@ static bool read_dib_body(QDataStream &s, const BMP_INFOHDR &bi, int offset, int
 
     if (depth != 32) {
         ncols = bi.biClrUsed ? bi.biClrUsed : 1 << nbits;
-        if (ncols > 256) // sanity check - don't run out of mem if color table is broken
+        if (ncols < 1 || ncols > 256) // sanity check - don't run out of mem if color table is broken
             return false;
         image.setColorCount(ncols);
     }
diff --git a/src/gui/image/qimage_p.h b/src/gui/image/qimage_p.h
index f9ad6c0ac0..0c0653e8ab 100644
--- a/src/gui/image/qimage_p.h
+++ b/src/gui/image/qimage_p.h
@@ -189,6 +189,12 @@ inline QImage::Format qt_alphaVersion(QImage::Format format)
     return QImage::Format_ARGB32_Premultiplied;
 }
 
+inline QImage::Format qt_maybeAlphaVersionWithSameDepth(QImage::Format format)
+{
+    const QImage::Format toFormat = qt_alphaVersion(format);
+    return qt_depthForFormat(format) == qt_depthForFormat(toFormat) ? toFormat : format;
+}
+
 inline QImage::Format qt_alphaVersionForPainting(QImage::Format format)
 {
     QImage::Format toFormat = qt_alphaVersion(format);