2 files changed, 6 insertions, 0 deletions
diff --git a/src/platformsupport/fontdatabases/fontconfig/qfontconfigdatabase.cpp b/src/platformsupport/fontdatabases/fontconfig/qfontconfigdatabase.cpp
index 17717dd53c..b8da9726d5 100644
--- a/src/platformsupport/fontdatabases/fontconfig/qfontconfigdatabase.cpp
+++ b/src/platformsupport/fontdatabases/fontconfig/qfontconfigdatabase.cpp
@@ -660,6 +660,9 @@ QFontEngine *QFontconfigDatabase::fontEngine(const QFontDef &f, void *usrPtr)
 QFontEngine *QFontconfigDatabase::fontEngine(const QByteArray &fontData, qreal pixelSize, QFont::HintingPreference hintingPreference)
 {
     QFontEngineFT *engine = static_cast<QFontEngineFT*>(QBasicFontDatabase::fontEngine(fontData, pixelSize, hintingPreference));
+    if (engine == 0)
+        return 0;
+
     QFontDef fontDef = engine->fontDef;
 
     QFontEngineFT::GlyphFormat format;
diff --git a/src/plugins/platforms/windows/qwindowsfontdatabase.cpp b/src/plugins/platforms/windows/qwindowsfontdatabase.cpp
index 940d75614c..6d9f01da4e 100644
--- a/src/plugins/platforms/windows/qwindowsfontdatabase.cpp
+++ b/src/plugins/platforms/windows/qwindowsfontdatabase.cpp
@@ -165,6 +165,9 @@ namespace {
         Q_ASSERT(tagName.size() == 4);
         quint32 tagId = *(reinterpret_cast<const quint32 *>(tagName.constData()));
 
+        if (m_fontData.size() < sizeof(OffsetSubTable) + sizeof(TableDirectory))
+            return 0;
+
         OffsetSubTable *offsetSubTable = reinterpret_cast<OffsetSubTable *>(m_fontData.data());
         TableDirectory *tableDirectory = reinterpret_cast<TableDirectory *>(offsetSubTable + 1);