commit 099a04f724accb56412b8bbb9cb1dba36a2f5264
author Tilman Hausherr <tilman@apache.org> Mon Aug 01 20:16:59 2016 +0000
committer Tilman Hausherr <tilman@apache.org> Mon Aug 01 20:16:59 2016 +0000
tree 0c6630cd9e430d821f3dae333f4a4fd1bdf862ee
parent 1601b3272882c4a048f0307c438ca7f2a7dade3d

PDFBOX-3446: avoid /Prev loop

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/trunk@1754793 13f79535-47bb-0310-9956-ffa450edef68

pdfbox/src/main/java/org/apache/pdfbox/pdfparser/COSParser.java

diff --git a/pdfbox/src/main/java/org/apache/pdfbox/pdfparser/COSParser.java b/pdfbox/src/main/java/org/apache/pdfbox/pdfparser/COSParser.java
index c08c727..4bd0611 100644
--- a/pdfbox/src/main/java/org/apache/pdfbox/pdfparser/COSParser.java
+++ b/pdfbox/src/main/java/org/apache/pdfbox/pdfparser/COSParser.java
@@ -208,8 +208,10 @@
         document.setStartXref(startXrefOffset);
         long prev = startXrefOffset;
         // ---- parse whole chain of xref tables/object streams using PREV reference
-        while (prev > 0)
+        long lastPrev = -1;
+        while (prev > 0 && prev != lastPrev)
         {
+            lastPrev = prev;
             // seek to xref table
             source.seek(prev);
 
@@ -298,6 +300,11 @@
                 }
             }
         }
+        if (prev == lastPrev)
+        {
+            //TODO better idea needed? PDFBOX-3446
+            throw new IOException("/Prev loop at offset " + prev);
+        }
         // ---- build valid xrefs out of the xref chain
         xrefTrailerResolver.setStartxref(startXrefOffset);
         COSDictionary trailer = xrefTrailerResolver.getTrailer();