From acda1ecd09e1aff7c2b9bbdca6e820021c4c9e4c Mon Sep 17 00:00:00 2001
From: wp_xxyyzz <wp_xxyyzz@8e941d3f-bd1b-0410-a28a-d453659cc2b4>
Date: Mon, 6 May 2019 15:50:39 +0000
Subject: [PATCH] fpspreadsheet: Fix memory leak due to rich-text streams in
 shared string table when reading biff8. Issue #35528, modified patch by
 Jurijs Romanovs.

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@6891 8e941d3f-bd1b-0410-a28a-d453659cc2b4
---
 .../fpspreadsheet/source/common/xlsbiff8.pas  | 21 +++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/components/fpspreadsheet/source/common/xlsbiff8.pas b/components/fpspreadsheet/source/common/xlsbiff8.pas
index dfdcd6ec7..1d68a6253 100644
--- a/components/fpspreadsheet/source/common/xlsbiff8.pas
+++ b/components/fpspreadsheet/source/common/xlsbiff8.pas
@@ -124,6 +124,7 @@ type
     FCommentLen: Integer;
     FBiff8ExternBooks: TsBiff8ExternBookList;
     FBiff8ExternSheetArray: array of TsBiff8ExternSheet;
+    procedure FreeSharedStringTable;
     function ReadString(const AStream: TStream; const ALength: Word;
       out ARichTextParams: TsRichTextParams): String;
     function ReadUnformattedWideString(const AStream: TStream;
@@ -786,8 +787,8 @@ begin
   SetLength(FBiff8ExternSheetArray, 0);
   FBiff8ExternBooks.Free;
 
-  { Destroy shared string table }
-  FSharedStringTable.Free;
+  { Destroy shared string table, as well as associated rich-text streams}
+  FreeSharedStringTable;
 
   { Destroy comment list }
   FCommentList.Free;
@@ -813,6 +814,19 @@ begin
   end;
 end;
 
+{@@ ----------------------------------------------------------------------------
+  Frees the shared string table. Also: destroys the rich-text memory streams
+  which can be assigned to string table items.
+-------------------------------------------------------------------------------}
+procedure TsSpreadBIFF8Reader.FreeSharedStringTable;
+var
+  j: Integer;
+begin
+  for j := 0 to FSharedStringTable.Count-1 do
+    TObject(FSharedStringTable.Objects[j]).Free;
+  FreeAndNil(FSharedStringTable);
+end;
+
 {@@ ----------------------------------------------------------------------------
   Populates the reader's default palette using the BIFF8 default colors.
 -------------------------------------------------------------------------------}
@@ -1122,8 +1136,7 @@ begin
     then FCommentList := TObjectList.Create
     else FCommentList.Clear;
 
-  if Assigned(FSharedStringTable) then
-    FreeAndNil(FSharedStringTable);
+  FreeSharedStringTable;
 
   while (not SectionEOF) do begin
     { Read the record header }