vcl/inc/pdf/ExternalPDFStreams.hxx | 12 ++++++++----
vcl/qa/cppunit/PDFDocumentTest.cxx | 12 ++++++++++++
vcl/qa/cppunit/data/DocumentWithNull.pdf |binary
vcl/source/filter/ipdf/pdfdocument.cxx | 12 +++++++++---
vcl/source/gdi/pdfwriter_impl.cxx | 12 +++++++++---
5 files changed, 38 insertions(+), 10 deletions(-)
New commits:
commit 2c1ed5a5dad827cde032f27a4348e81be15889bc
Author: Tomaž Vajngerl <tomaz.vajng...@collabora.co.uk>
AuthorDate: Tue Mar 2 18:57:46 2021 +0900
Commit: Tomaž Vajngerl <qui...@gmail.com>
CommitDate: Wed Mar 3 02:00:16 2021 +0100
tdf#140606 make PDF parsing more lenient and prevent a crash
If the external document can't be opened, it tried to continue
with the export anyway, which eventually lead to a crash. This
is fixed by handling this situation and prevent a crash, however
the part of the document in this case isn't exported.
The document couldn't be opened because of a parsing error - there
was a unexpected null character instead of a whitespace, which
made the parser panic. Fix this by making the parser more lenient
in such a situation when there is an unexpected null and try to
continue parsing.
Bug document seems to be created with a buggy PDF writer, but other
PDF readers don't complain when parsing the document so it looks to
be a valid. qpdf --check doesn't complain either.
Added a test that checks a document with a null parses.
Change-Id: I61eb281e821ccd195ef006d778556e25d1c7f5e3
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/111820
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <qui...@gmail.com>
diff --git a/vcl/inc/pdf/ExternalPDFStreams.hxx
b/vcl/inc/pdf/ExternalPDFStreams.hxx
index dc484e1dd15b..7840217630c8 100644
--- a/vcl/inc/pdf/ExternalPDFStreams.hxx
+++ b/vcl/inc/pdf/ExternalPDFStreams.hxx
@@ -34,21 +34,25 @@ struct VCL_DLLPUBLIC ExternalPDFStream
std::map<sal_Int32, sal_Int32>& getCopiedResources() { return
maCopiedResources; }
- filter::PDFDocument& getPDFDocument()
+ std::shared_ptr<filter::PDFDocument>& getPDFDocument()
{
if (!mpPDFDocument)
{
SvMemoryStream aPDFStream;
aPDFStream.WriteBytes(maDataContainer.getData(),
maDataContainer.getSize());
aPDFStream.Seek(0);
- mpPDFDocument = std::make_shared<filter::PDFDocument>();
- if (!mpPDFDocument->Read(aPDFStream))
+ auto pPDFDocument = std::make_shared<filter::PDFDocument>();
+ if (!pPDFDocument->Read(aPDFStream))
{
SAL_WARN("vcl.pdfwriter",
"PDFWriterImpl::writeReferenceXObject: reading the
PDF document failed");
}
+ else
+ {
+ mpPDFDocument = pPDFDocument;
+ }
}
- return *mpPDFDocument;
+ return mpPDFDocument;
}
};
diff --git a/vcl/qa/cppunit/PDFDocumentTest.cxx
b/vcl/qa/cppunit/PDFDocumentTest.cxx
index 2246f8e38924..35af8e66cd58 100644
--- a/vcl/qa/cppunit/PDFDocumentTest.cxx
+++ b/vcl/qa/cppunit/PDFDocumentTest.cxx
@@ -156,6 +156,18 @@ CPPUNIT_TEST_FIXTURE(PDFDocumentTest, testParseBasicPDF)
}
}
+CPPUNIT_TEST_FIXTURE(PDFDocumentTest, testParseDocumentWithNullAsWhitespace)
+{
+ // tdf#140606
+ // Bug document contained a null, which cause the parser to panic,
+ // but other PDF readers can handle the file well.
+
+ OUString aURL = m_directories.getURLFromSrc(DATA_DIRECTORY) +
"DocumentWithNull.pdf";
+ vcl::filter::PDFDocument aDocument;
+ SvFileStream aStream(aURL, StreamMode::READ);
+ CPPUNIT_ASSERT(aDocument.Read(aStream));
+}
+
namespace
{
vcl::filter::PDFObjectElement*
diff --git a/vcl/qa/cppunit/data/DocumentWithNull.pdf
b/vcl/qa/cppunit/data/DocumentWithNull.pdf
new file mode 100644
index 000000000000..f6d926957366
Binary files /dev/null and b/vcl/qa/cppunit/data/DocumentWithNull.pdf differ
diff --git a/vcl/source/filter/ipdf/pdfdocument.cxx
b/vcl/source/filter/ipdf/pdfdocument.cxx
index acf584949a70..5ebe05e6115a 100644
--- a/vcl/source/filter/ipdf/pdfdocument.cxx
+++ b/vcl/source/filter/ipdf/pdfdocument.cxx
@@ -1324,12 +1324,18 @@ bool PDFDocument::Tokenize(SvStream& rStream,
TokenizeMode eMode,
}
else
{
- if (!rtl::isAsciiWhiteSpace(static_cast<unsigned
char>(ch)))
+ auto uChar = static_cast<unsigned char>(ch);
+ // Be more lenient and allow unexpected null char
+ if (!rtl::isAsciiWhiteSpace(uChar) && uChar != 0)
{
- SAL_WARN("vcl.filter", "PDFDocument::Tokenize:
unexpected character: "
- << ch << " at byte position
" << rStream.Tell());
+ SAL_WARN("vcl.filter",
+ "PDFDocument::Tokenize: unexpected character
with code "
+ << sal_Int32(ch) << " at byte position "
<< rStream.Tell());
return false;
}
+ SAL_WARN_IF(uChar == 0, "vcl.filter",
+ "PDFDocument::Tokenize: unexpected null
character at "
+ << rStream.Tell() << " - ignoring");
}
break;
}
diff --git a/vcl/source/gdi/pdfwriter_impl.cxx
b/vcl/source/gdi/pdfwriter_impl.cxx
index 967dcf62dece..f7c6f827eba5 100644
--- a/vcl/source/gdi/pdfwriter_impl.cxx
+++ b/vcl/source/gdi/pdfwriter_impl.cxx
@@ -8458,10 +8458,16 @@ void
PDFWriterImpl::writeReferenceXObject(ReferenceXObjectEmit& rEmit)
// object.
if (rEmit.m_nExternalPDFDataIndex < 0)
return;
- auto & rExternalPDFStream =
m_aExternalPDFStreams.get(rEmit.m_nExternalPDFDataIndex);
- auto & rPDFDocument = rExternalPDFStream.getPDFDocument();
+ auto& rExternalPDFStream =
m_aExternalPDFStreams.get(rEmit.m_nExternalPDFDataIndex);
+ auto& pPDFDocument = rExternalPDFStream.getPDFDocument();
+ if (!pPDFDocument)
+ {
+ // Couldn't parse the document and can't continue
+ SAL_WARN("vcl.pdfwriter", "PDFWriterImpl::writeReferenceXObject:
failed to parse the document");
+ return;
+ }
- std::vector<filter::PDFObjectElement*> aPages =
rPDFDocument.GetPages();
+ std::vector<filter::PDFObjectElement*> aPages =
pPDFDocument->GetPages();
if (aPages.empty())
{
SAL_WARN("vcl.pdfwriter", "PDFWriterImpl::writeReferenceXObject:
no pages");
_______________________________________________
Libreoffice-commits mailing list
libreoffice-comm...@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/libreoffice-commits
