Re: [Podofo-users] integer overflow in PdfObjectStreamParserObject::ReadObjectsFromStream (src/base/PdfObjectStreamParserObject.cpp)

[zyx <zy...@gm...>]

On Thu, 2018-01-11 at 16:59 -0500, Probe Fuzzer wrote:
> src/base/PdfObjectStreamParserObject.cpp:99:30: runtime error: signed
> integer overflow: 94 + 9223372036854775807 cannot be represented in
> type 'long int'

	Hi,
the line 99 of that file looks like this:

  device.Device()->Seek( static_cast<std::streamoff>(lFirst + lOff) );

where both lFirst and lOff are 64bit integers, thus it all depends on
the statis_Cast and the size of streamoff, whose size may depend on
large file support being enabled or not. That's not a problem of
PoDoFo, is it?
  
> To reproduce the issue, compile libming with UBSAN "-
> fsanitize=undefined",

What is libming, please? I do not seem to have it here.

I'm also not able to reproduce this locally, using svn trunk at
revision 1866. I build PoDoFo with more than that sanitize flag and
nothing had been caught by the address sanitizer. The call ended with:

   Error: An error 5 ocurred during processing the pdf file.

   PoDoFo encountered an error. Error: 5 ePdfError_UnexpectedEOF
	Error Description: End of file was reached unxexpectedly.
	Callstack:
	#0 Error Source: .../src/base/PdfParser.cpp:232
		Information: Unable to load objects from file.
	#1 Error Source: .../src/base/PdfTokenizer.cpp:386
		Information: Expected variant.

and no segfault or anything like that.
	Bye,
	zyx