8272594: Better record of recordings

Reviewed-by: mgronlun, rhalade, mschoene

Author: egahlin

src/jdk.jfr/share/classes/jdk/jfr/internal/MetadataReader.java

@@ -66,6 +66,7 @@ final class MetadataReader {
     public MetadataReader(RecordingInput input) throws IOException {
         this.input = input;
         int size = input.readInt();
+        input.require(size, "Metadata string pool size %d exceeds available data" );
         this.pool = new ArrayList<>(size);
         StringParser p = new StringParser(null, false);
         for (int i = 0; i < size; i++) {

src/jdk.jfr/share/classes/jdk/jfr/internal/consumer/ParserFactory.java

@@ -296,6 +296,7 @@ public ArrayParser(Parser elementParser) {
         @Override
         public Object parse(RecordingInput input) throws IOException {
             final int size = input.readInt();
+            input.require(size, "Array size %d exceeds available data" );
             final Object[] array = new Object[size];
             for (int i = 0; i < size; i++) {
                 array[i] = elementParser.parse(input);

src/jdk.jfr/share/classes/jdk/jfr/internal/consumer/RecordingInput.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -418,6 +418,15 @@ public String getFilename() {
         return filename;
     }
 
+    // Purpose of this method is to prevent OOM by sanity check
+    // the minimum required number of bytes against what is available in
+    // segment/chunk/file
+    public void require(int minimumBytes, String errorMessage) throws IOException {
+        if (position + minimumBytes > size) {
+            throw new IOException(String.format(errorMessage, minimumBytes));
+        }
+    }
+
     // Purpose of this method is to reuse block cache from a
     // previous RecordingInput
     public void setFile(Path path) throws IOException {

src/jdk.jfr/share/classes/jdk/jfr/internal/consumer/StringParser.java

@@ -70,6 +70,7 @@ private static final class CharsetParser extends Parser {
         @Override
         public Object parse(RecordingInput input) throws IOException {
             int size = input.readInt();
+            input.require(size, "String size %d exceeds available data");
             ensureSize(size);
             if (lastSize == size) {
                 boolean equalsLastString = true;
@@ -115,6 +116,7 @@ private static final class CharArrayParser extends Parser {
         @Override
         public Object parse(RecordingInput input) throws IOException {
             int size = input.readInt();
+            input.require(size, "String size %d exceeds available data");
             ensureSize(size);
             if (lastSize == size) {
                 boolean equalsLastString = true;