commit f903fcf5445a1194db53a7187566919a87e8e3eb
Author: Vasily Dybala <Vasily.Dybala@kaspersky.com>
Date:   Wed May 19 16:06:31 2021 +0300

    qregion: Fix integer overflow on innerArea.
    
    If height and width are extremly big, it is possible
    that integer overflow will be during area calculation.
    
    Change-Id: I83b8d0e326688882f3f1b8af85ba5dd01c8a6abd
    Fix: QTBUG-93840

diff --git a/src/gui/painting/qregion.cpp b/src/gui/painting/qregion.cpp
index 77718ce747..38caa5dbbb 100644
--- a/src/gui/painting/qregion.cpp
+++ b/src/gui/painting/qregion.cpp
@@ -1240,7 +1240,7 @@ struct QRegionPrivate {
     inline QRegionPrivate() : numRects(0), innerArea(-1) {}
     inline QRegionPrivate(const QRect &r)
         : numRects(1),
-          innerArea(r.width() * r.height()),
+          innerArea(int(qint64(r.width()) * r.height() < INT_MAX ?: INT_MAX)),
           extents(r),
           innerRect(r)
     {