Merge remote-tracking branch 'origin/tqtc/lts-5.15.10' into tqtc/lts-5.15-opensourcev5.15.10-lts-lgpl

Change-Id: Ic1bb4240ca70a8a361fa0267476707446579221d

1 files changed, 7 insertions, 3 deletions

diff --git a/src/corelib/io/qbuffer.cpp b/src/corelib/io/qbuffer.cpp
index 595fcd2724..5c562623e2 100644
--- a/src/corelib/io/qbuffer.cpp
+++ b/src/corelib/io/qbuffer.cpp
@@ -41,6 +41,8 @@
 #include <QtCore/qmetaobject.h>
 #include "private/qiodevice_p.h"
 
+#include <limits>
+
 QT_BEGIN_NAMESPACE
 
 /** QBufferPrivate **/
@@ -212,7 +214,7 @@ QBuffer::~QBuffer()
 }
 
 /*!
-    Makes QBuffer uses the QByteArray pointed to by \a
+    Makes QBuffer use the QByteArray pointed to by \a
     byteArray as its internal buffer. The caller is responsible for
     ensuring that \a byteArray remains valid until the QBuffer is
     destroyed, or until setBuffer() is called to change the buffer.
@@ -366,7 +368,9 @@ qint64 QBuffer::size() const
 bool QBuffer::seek(qint64 pos)
 {
     Q_D(QBuffer);
-    if (pos > d->buf->size() && isWritable()) {
+    const auto oldBufSize = d->buf->size();
+    constexpr qint64 MaxSeekPos = (std::numeric_limits<decltype(oldBufSize)>::max)();
+    if (pos <= MaxSeekPos && pos > oldBufSize && isWritable()) {
         if (seek(d->buf->size())) {
             const qint64 gapSize = pos - d->buf->size();
             if (write(QByteArray(gapSize, 0)) != gapSize) {
@@ -377,7 +381,7 @@ bool QBuffer::seek(qint64 pos)
             return false;
         }
     } else if (pos > d->buf->size() || pos < 0) {
-        qWarning("QBuffer::seek: Invalid pos: %d", int(pos));
+        qWarning("QBuffer::seek: Invalid pos: %lld", pos);
         return false;
     }
     return QIODevice::seek(pos);