From: Steve Lhomme <slhomme@matroska.org>
Date: Wed, 6 Dec 2017 09:32:13 +0100
Subject: Do not output an element with size Unknown if it's not allowed

Similar to what is done in FindNextID().

SetSizeInfinite() doesn't actually set anything. SetSizeIsFinite() is the one
that actually sets it and it is an internal API.
---
 src/EbmlElement.cpp | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/src/EbmlElement.cpp b/src/EbmlElement.cpp
index b92522e..26510c7 100644
--- a/src/EbmlElement.cpp
+++ b/src/EbmlElement.cpp
@@ -451,15 +451,13 @@ EbmlElement * EbmlElement::FindNextElement(IOCallback & DataStream, const EbmlSe
           //  1 : same level
           //  + : further parent
           if (Result->ValidateSize() && (SizeFound == SizeUnknown || UpperLevel > 0 || MaxDataSize == 0 || MaxDataSize >= (PossibleID_Length + PossibleSizeLength + SizeFound))) {
-            if (SizeFound == SizeUnknown) {
-              Result->SetSizeInfinite();
+            if (SizeFound != SizeUnknown || Result->SetSizeInfinite()) {
+              Result->SizePosition = DataStream.getFilePointer() - SizeIdx + EBML_ID_LENGTH(PossibleID);
+              Result->ElementPosition = Result->SizePosition - EBML_ID_LENGTH(PossibleID);
+              // place the file at the beggining of the data
+              DataStream.setFilePointer(Result->SizePosition + _SizeLength);
+              return Result;
             }
-
-            Result->SizePosition = DataStream.getFilePointer() - SizeIdx + EBML_ID_LENGTH(PossibleID);
-            Result->ElementPosition = Result->SizePosition - EBML_ID_LENGTH(PossibleID);
-            // place the file at the beggining of the data
-            DataStream.setFilePointer(Result->SizePosition + _SizeLength);
-            return Result;
           }
         }
         delete Result;