Check for negative page size in FindTextlineFlowOrientation()

core/fpdftext/cpdf_textpage.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "core/fpdftext/include/cpdf_textpage.h"
 
 #include <algorithm>
 #include <utility>
@@ skipping 489 matching lines @@
   bottom = m_SelRects[rectIndex].bottom;
 }
 
 CPDF_TextPage::TextOrientation CPDF_TextPage::FindTextlineFlowOrientation()
     const {
   if (m_pPage->GetPageObjectList()->empty())
     return TextOrientation::Unknown;
 
   const int32_t nPageWidth = static_cast<int32_t>(m_pPage->GetPageWidth());
   const int32_t nPageHeight = static_cast<int32_t>(m_pPage->GetPageHeight());
+  if (nPageWidth <= 0 || nPageHeight <= 0)
+    return TextOrientation::Unknown;
+
   std::vector<bool> nHorizontalMask(nPageWidth);
   std::vector<bool> nVerticalMask(nPageHeight);
   FX_FLOAT fLineHeight = 0.0f;
   int32_t nStartH = nPageWidth;
   int32_t nEndH = 0;
   int32_t nStartV = nPageHeight;
   int32_t nEndV = 0;
   for (const auto& pPageObj : *m_pPage->GetPageObjectList()) {
     if (!pPageObj->IsText())
       continue;
@@ skipping 1009 matching lines @@
                                  info.m_OriginY);
   return TRUE;
 }
 
 FX_BOOL CPDF_TextPage::IsRectIntersect(const CFX_FloatRect& rect1,
                                        const CFX_FloatRect& rect2) {
   CFX_FloatRect rect = rect1;
   rect.Intersect(rect2);
   return !rect.IsEmpty();
 }