From ef619d0562b39f30943cfdc4985a0df233d00e42 Mon Sep 17 00:00:00 2001 From: Jun Fang Date: Wed, 19 Nov 2014 18:58:01 -0800 Subject: Fix blank page issues caused by too strict check Before this fix, PDF parser aborts the parsering process when detecting an error. For this case, PDF parser just gives up parsering when it detects that the length of image stream is incorrect. The solution to this case is to find the tag "endstream" and "endobj" to calculate the length rather than aborting the parsering process. BUG=433339 R=tsepez@chromium.org Review URL: https://codereview.chromium.org/743263002 --- core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) (limited to 'core/src/fpdfapi') diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp index 029913458a..86ffae2f6e 100644 --- a/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp +++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp @@ -2433,16 +2433,13 @@ CPDF_Stream* CPDF_SyntaxParser::ReadStream(CPDF_Dictionary* pDict, PARSE_CONTEXT pContext->m_DataStart = m_Pos; } - base::CheckedNumeric pos = m_Pos; - pos += len; - if (pos.IsValid() && pos.ValueOrDie() < m_FileLen) { - m_Pos = pos.ValueOrDie(); - } else { - return NULL; - } - CPDF_CryptoHandler* pCryptoHandler = objnum == (FX_DWORD)m_MetadataObjnum ? NULL : m_pCryptoHandler; if (pCryptoHandler == NULL) { + base::CheckedNumeric pos = m_Pos; + pos += len; + if (pos.IsValid() && pos.ValueOrDie() < m_FileLen) { + m_Pos = pos.ValueOrDie(); + } GetNextWord(); if (m_WordSize < 9 || FXSYS_memcmp32(m_WordBuffer, "endstream", 9)) { m_Pos = StreamStartPos; @@ -2473,8 +2470,8 @@ CPDF_Stream* CPDF_SyntaxParser::ReadStream(CPDF_Dictionary* pDict, PARSE_CONTEXT } } } + m_Pos = StreamStartPos; } - m_Pos = StreamStartPos; CPDF_Stream* pStream; #if defined(_FPDFAPI_MINI_) && !defined(_FXCORE_FEATURE_ALL_) pStream = FX_NEW CPDF_Stream(m_pFileAccess, pCryptoHandler, m_HeaderOffset + m_Pos, len, pDict, gennum); -- cgit v1.2.3