forcepoint#66 make sure we don't get stuck endlessly reparsing

Change-Id: Ie2733e8d7f73e5f6a072604c477e949cd944189a
Reviewed-on: https://gerrit.libreoffice.org/58466
Tested-by: Jenkins
Reviewed-by: Michael Stahl <Michael.Stahl@cib.de>
(cherry picked from commit cc8140fe71becc92976167e2a96dbe1d727097dc)
(cherry picked from commit fab30b5d512edf8d5252ddde4132b0f310431afd)

1 files changed, 8 insertions, 3 deletions

diff --git a/vcl/source/filter/ipdf/pdfdocument.cxx b/vcl/source/filter/ipdf/pdfdocument.cxx
index 83560394ba4c..5661e605bee5 100644
--- a/vcl/source/filter/ipdf/pdfdocument.cxx
+++ b/vcl/source/filter/ipdf/pdfdocument.cxx
@@ -2226,9 +2226,14 @@ size_t PDFDictionaryElement::Parse(const std::vector< std::unique_ptr<PDFElement
             else if (!pDictionary->alreadyParsing())
             {
                 // Nested dictionary.
-                i = PDFDictionaryElement::Parse(rElements, pDictionary, pDictionary->m_aItems);
-                rDictionary[aName] = pDictionary;
-                aName.clear();
+                const size_t nexti
+                    = PDFDictionaryElement::Parse(rElements, pDictionary, pDictionary->m_aItems);
+                if (nexti >= i) // ensure we go forwards and not endlessly loop
+                {
+                    i = nexti;
+                    rDictionary[aName] = pDictionary;
+                    aName.clear();
+                }
             }
         }