Bug 691349

Summary:	pdf_loadobjstm: don't overwrite object reference in xref with older version
Product:	MuPDF	Reporter:	zeniko
Component:	mupdf	Assignee:	Tor Andersson <tor.andersson>
Status:	RESOLVED FIXED
Severity:	normal
Priority:	P4
Version:	unspecified
Hardware:	PC
OS:	Windows 7
URL:	http://code.google.com/p/sumatrapdf/issues/detail?id=926
Customer:		Word Size:	---

Description zeniko 2010-05-29 21:35:15 UTC

Steps to reproduce:
* Load http://mobile.carrefour.fr/pdf/guide-achat.pdf at page 1 and navigate to page 4.
* Load the same document directly at page 4 and navigate to page 6.

Actual results:
In the first case, many letters are missing from page 4 due to an incomplete (older revision) of a partial font being loaded.
In the second case, page 4 renders just fine but the same issue applies to page 6.

See http://code.google.com/p/sumatrapdf/source/detail?r=1922 for a patch.

Comment 1 zeniko 2010-05-29 22:28:29 UTC

Well, http://code.google.com/p/sumatrapdf/source/detail?r=1923 would be the version which actually works...

Comment 2 zeniko 2010-05-29 23:05:04 UTC

A variation of the same issue can be found at http://drop.io/mdj12345 (from http://code.google.com/p/sumatrapdf/issues/detail?id=936 ): in this document, the object numbers of old xrefs are re-used, but due to the fact that pdf_readnewxref works backwards, the table entries are overwritten nonetheless.

See http://code.google.com/p/sumatrapdf/source/detail?r=1924 for a patch for this second issue.

Comment 3 Tor Andersson 2010-05-31 20:49:41 UTC

I've pushed patches that fix the xref table clobbering in both of these cases.

Comment 4 zeniko 2010-05-31 21:17:43 UTC

FYI: Your first fix introduced a memory leak due to unused objects not being dropped.