Better PNG chunk length error message

Closes #272
drewnoakes · Nov 24, 2017 · e91bdb3 · e91bdb3
1 parent 52cdffe
commit e91bdb3
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/Source/com/drew/imaging/png/PngChunkReader.java b/Source/com/drew/imaging/png/PngChunkReader.java
@@ -86,6 +86,9 @@ public Iterable<PngChunk> extract(@NotNull final SequentialReader reader, @Nulla
             // Process the next chunk.
             int chunkDataLength = reader.getInt32();
 
+            if (chunkDataLength < 0)
+                throw new PngProcessingException("PNG chunk length exceeds maximum");
+
             PngChunkType chunkType = new PngChunkType(reader.getBytes(4));
 
             boolean willStoreChunk = desiredChunkTypes == null || desiredChunkTypes.contains(chunkType);