diff --git a/src/gui/text/qfontengine.cpp b/src/gui/text/qfontengine.cpp
index d4eeee5aefa..d33965b5ea1 100644
--- a/src/gui/text/qfontengine.cpp
+++ b/src/gui/text/qfontengine.cpp
@@ -473,6 +473,9 @@ bool QFontEngine::processOS2Table() const
             // Some fonts may have invalid OS/2 data. We detect this and bail out.
             if (winAscent == 0 && winDescent == 0)
                 return false;
+            const auto limitForQFixed = std::numeric_limits<int>::max() / (fontDef.pixelSize * 64);
+            if (winAscent > limitForQFixed || winDescent > limitForQFixed)
+                return false;
             m_ascent = QFixed::fromReal(winAscent * fontDef.pixelSize) / unitsPerEm;
             m_descent = QFixed::fromReal(winDescent * fontDef.pixelSize) / unitsPerEm;
             m_leading = QFixed{};
diff --git a/tests/auto/gui/text/qfontmetrics/tst_qfontmetrics.cpp b/tests/auto/gui/text/qfontmetrics/tst_qfontmetrics.cpp
index 429eab131a6..5e0a974ab9c 100644
--- a/tests/auto/gui/text/qfontmetrics/tst_qfontmetrics.cpp
+++ b/tests/auto/gui/text/qfontmetrics/tst_qfontmetrics.cpp
@@ -39,6 +39,7 @@ private slots:
     void typoLineMetrics();
     void defaultIgnorableHorizontalAdvance_data();
     void defaultIgnorableHorizontalAdvance();
+    void hugeFontMetrics();
 };
 
 void tst_QFontMetrics::same()
@@ -511,5 +512,21 @@ void tst_QFontMetrics::defaultIgnorableHorizontalAdvance()
     QCOMPARE_GT(withSupportWithIgnorablesAdvance, withSupportWithoutIgnorablesAdvance);
 }
 
+void tst_QFontMetrics::hugeFontMetrics()
+{
+    QFont bigFont;
+    bigFont.setPixelSize(10000);
+
+    QFont hugeFont;
+    hugeFont.setPixelSize(32000);
+
+    QFont hugeFontWithTypoLineMetrics;
+    hugeFontWithTypoLineMetrics.setStyleStrategy(QFont::PreferTypoLineMetrics);
+    hugeFontWithTypoLineMetrics.setPixelSize(30000);
+
+    QVERIFY(QFontMetricsF(bigFont).height() < QFontMetricsF(hugeFont).height());
+    QVERIFY(QFontMetricsF(bigFont).height() < QFontMetricsF(hugeFontWithTypoLineMetrics).height());
+}
+
 QTEST_MAIN(tst_QFontMetrics)
 #include "tst_qfontmetrics.moc"