Detect resursive loading of type3 font char to avoid infinite loop

core/fpdfapi/fpdf_font/cpdf_cidfont.cpp

 // Copyright 2016 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/fpdfapi/fpdf_font/cpdf_cidfont.h"
 
 #include <algorithm>
 #include <vector>
@@ skipping 410 matching lines @@
       m_DefaultVY = pDefaultArray->GetIntegerAt(0);
       m_DefaultW1 = pDefaultArray->GetIntegerAt(1);
     } else {
       m_DefaultVY = 880;
       m_DefaultW1 = -1000;
     }
   }
   return true;
 }
 
-FX_RECT CPDF_CIDFont::GetCharBBox(uint32_t charcode, int level) {
+FX_RECT CPDF_CIDFont::GetCharBBox(uint32_t charcode) {
   if (charcode < 256 && m_CharBBox[charcode].right != -1)
     return m_CharBBox[charcode];
 
   FX_RECT rect;
   bool bVert = false;
   int glyph_index = GlyphFromCharCode(charcode, &bVert);
   FXFT_Face face = m_Font.GetFace();
   if (face) {
     if (FXFT_Is_Face_Tricky(face)) {
       int err = FXFT_Load_Glyph(face, glyph_index,
@@ skipping 50 matching lines @@
       rect_f.Transform(&matrix);
       rect = rect_f.GetOuterRect();
     }
   }
   if (charcode < 256)
     m_CharBBox[charcode] = rect;
 
   return rect;
 }
 
-int CPDF_CIDFont::GetCharWidthF(uint32_t charcode, int level) {
+int CPDF_CIDFont::GetCharWidthF(uint32_t charcode) {
   if (charcode < 0x80 && m_bAnsiWidthsFixed)
     return (charcode >= 32 && charcode < 127) ? 500 : 0;
 
   uint16_t cid = CIDFromCharCode(charcode);
   int size = m_WidthList.GetSize();
   const uint32_t* pList = m_WidthList.GetData();
   for (int i = 0; i < size; i += 3) {
     const uint32_t* pEntry = pList + i;
     if (IsMetricForCID(pEntry, cid))
       return static_cast<int>(pEntry[2]);
@@ skipping 330 matching lines @@
   if (m_Charset != CIDSET_JAPAN1 || m_pFontFile)
     return nullptr;
 
   const auto* pEnd = g_Japan1_VertCIDs + FX_ArraySize(g_Japan1_VertCIDs);
   const auto* pTransform = std::lower_bound(
       g_Japan1_VertCIDs, pEnd, CID,
       [](const CIDTransform& entry, uint16_t cid) { return entry.cid < cid; });
   return (pTransform < pEnd && CID == pTransform->cid) ? &pTransform->a
                                                        : nullptr;
 }