fix: when using TBarcodeFormat.Auto certain QRCodes causes integer overflow in EAN parser. #133

Author: E Spelt

Lib/Classes/1D Barcodes/ZXing.OneD.UPCEANReader.pas

@@ -451,7 +451,12 @@ function TUPCEANReader.decodeRow(const rowNumber: Integer; const row: IBitArray;
   if startRange = nil then
     exit(nil);
 
-  Result := DoDecodeRow(rowNumber, row, startRange, hints);
+  try
+    Result := DoDecodeRow(rowNumber, row, startRange, hints);
+  except
+    result := nil;
+  end;
+
 end;
 
 function TUPCEANReader.DoDecodeRow(const rowNumber: Integer;

README.md

@@ -38,6 +38,8 @@ The standard camera component is, I think too slow for Android and IOS. You need
 
 
 ### Changes
+- v3.9.4
+	- fix: when using TBarcodeFormat.Auto certain QRCodes causes integer overflow in EAN parser. https://github.com/Spelt/ZXing.Delphi/issues/133
 - v3.9.3
 	- Demo app is Alexandria/Android compatible (Thanks igorbastosib and Patrick Prémartin)
 	- fix: Some boundary check added (Thanks igorbastosib)

UnitTest/Test.pas

@@ -533,6 +533,16 @@ procedure TZXingDelphiTest.AllQRCode();
     FreeAndNil(result);
   end;
 
+
+   try
+    result := Decode('QR-bug-overflow.png', TBarcodeFormat.QR_CODE);
+    Assert.IsNotNull(result, ' Nil result');
+    Assert.Contains(result.Text, '1653015096', false);
+
+  finally
+    FreeAndNil(result);
+  end;
+
 end;
 
 // This ones will only work when PURE_BARCODE is existing in the additional hints.
@@ -542,8 +552,6 @@ procedure TZXingDelphiTest.All_PURE_QRCode();
   hints: TDictionary<TDecodeHintType, TObject>;
 begin
 
-
-
   hints := TDictionary<TDecodeHintType, TObject>.Create();
   hints.Add(TDecodeHintType.PURE_BARCODE, nil);
 
@@ -1089,11 +1097,18 @@ procedure TZXingDelphiTest.AutoTypes;
 var
   result: TReadResult;
 begin
+
+  try
+    result := Decode('QR-bug-overflow.png', TBarcodeFormat.EAN_13);
+    Assert.IsNull(result, ' Nil result');
+  finally
+    FreeAndNil(result);
+  end;
+
   try
     result := Decode('Code128.png', TBarcodeFormat.Auto);
     Assert.IsNotNull(result, ' Nil result ');
     Assert.IsTrue(result.Text.Equals('1234567'), 'Code 128 result Text Incorrect: ' + result.Text);
-
   finally
     FreeAndNil(result);
   end;
@@ -1111,7 +1126,6 @@ procedure TZXingDelphiTest.AutoTypes;
     result := Decode('Code128.png', TBarcodeFormat.Auto);
     Assert.IsNotNull(result, ' Nil result ');
     Assert.IsTrue(result.Text.Equals('1234567'), 'Code 128 result Text Incorrect: ' + result.Text);
-
   finally
     FreeAndNil(result);
   end;
@@ -1214,6 +1228,7 @@ procedure TZXingDelphiTest.AutoTypes;
   finally
     FreeAndNil(result);
   end;
+
 end;
 
 /// /////////////////////////////////////////////////////////////////////////////