Issue #4538 - add invalid utf8 validation tests for MessageReader

Signed-off-by: Lachlan Roberts <lachlan@webtide.com>

jetty-websocket/websocket-util/src/main/java/org/eclipse/jetty/websocket/util/messages/MessageReader.java

@@ -23,6 +23,7 @@ import java.io.Reader;
 import java.nio.ByteBuffer;
 import java.nio.CharBuffer;
 import java.nio.charset.CharsetDecoder;
+import java.nio.charset.CoderResult;
 import java.nio.charset.CodingErrorAction;
 import java.nio.charset.StandardCharsets;
 
@@ -63,19 +64,25 @@ public class MessageReader extends Reader implements MessageSink
     public int read(char[] cbuf, int off, int len) throws IOException
     {
         CharBuffer charBuffer = CharBuffer.wrap(cbuf, off, len);
-        if (!buffer.hasRemaining())
+        boolean endOfInput = false;
+        while (true)
         {
             int read = stream.read(buffer);
             if (read == 0)
-                return read;
+                break;
             if (read < 0)
             {
-                utf8Decoder.decode(BufferUtil.EMPTY_BUFFER, charBuffer, true);
-                return (charBuffer.position() > 0) ? charBuffer.position() : read;
+                endOfInput = true;
+                break;
             }
         }
 
-        utf8Decoder.decode(buffer, charBuffer, false);
+        CoderResult result = utf8Decoder.decode(buffer, charBuffer, endOfInput);
+        if (result.isError())
+            result.throwException();
+
+        if (endOfInput && (charBuffer.position() == 0))
+            return -1;
         return charBuffer.position();
     }
 

jetty-websocket/websocket-util/src/test/java/org/eclipse/jetty/websocket/util/MessageReaderTest.java

@@ -1,12 +1,34 @@
+//
+// ========================================================================
+// Copyright (c) 1995-2020 Mort Bay Consulting Pty Ltd and others.
+//
+// This program and the accompanying materials are made available under
+// the terms of the Eclipse Public License 2.0 which is available at
+// https://www.eclipse.org/legal/epl-2.0
+//
+// This Source Code may also be made available under the following
+// Secondary Licenses when the conditions for such availability set
+// forth in the Eclipse Public License, v. 2.0 are satisfied:
+// the Apache License v2.0 which is available at
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
+// ========================================================================
+//
+
 package org.eclipse.jetty.websocket.util;
 
 import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.charset.MalformedInputException;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 
+import org.eclipse.jetty.util.BufferUtil;
 import org.eclipse.jetty.util.FutureCallback;
 import org.eclipse.jetty.util.IO;
+import org.eclipse.jetty.util.StringUtil;
 import org.eclipse.jetty.websocket.core.Frame;
 import org.eclipse.jetty.websocket.core.OpCode;
 import org.eclipse.jetty.websocket.util.messages.MessageReader;
@@ -90,10 +112,25 @@ public class MessageReaderTest
         assertThat(cause.getMessage(), is("Closed"));
     }
 
+    @Test
+    public void testInvalidUtf8() throws Exception
+    {
+        ByteBuffer invalidUtf8Payload = BufferUtil.toBuffer(new byte[]{0x7F, (byte)0xFF, (byte)0xFF});
+        giveByteBuffer(invalidUtf8Payload, true);
+
+        ExecutionException error = assertThrows(ExecutionException.class, () -> message.get(5, TimeUnit.SECONDS));
+        assertThat(error.getCause(), instanceOf(MalformedInputException.class));
+    }
+
     private void giveString(String s, boolean last) throws IOException
+    {
+        giveByteBuffer(ByteBuffer.wrap(StringUtil.getUtf8Bytes(s)), last);
+    }
+
+    private void giveByteBuffer(ByteBuffer buffer, boolean last) throws IOException
     {
         byte opCode = first ? OpCode.TEXT : OpCode.CONTINUATION;
-        Frame frame = new Frame(opCode, last, s);
+        Frame frame = new Frame(opCode, last, buffer);
         FutureCallback callback = new FutureCallback();
         reader.accept(frame, callback);
         callback.block(5, TimeUnit.SECONDS);