Release ByteBuf

Closes gh-9661

rsocket/src/main/java/org/springframework/security/rsocket/authentication/AuthenticationPayloadExchangeConverter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2019 the original author or authors.
+ * Copyright 2019-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -71,7 +71,9 @@ public class AuthenticationPayloadExchangeConverter implements PayloadExchangeAu
 		if (authenticationMetadata == null) {
 			return null;
 		}
-		ByteBuf rawAuthentication = ByteBufAllocator.DEFAULT.buffer().writeBytes(authenticationMetadata);
+		ByteBuf rawAuthentication = ByteBufAllocator.DEFAULT.buffer();
+		try {
+			rawAuthentication.writeBytes(authenticationMetadata);
 			if (!AuthMetadataCodec.isWellKnownAuthType(rawAuthentication)) {
 				return null;
 			}
@@ -84,6 +86,10 @@ public class AuthenticationPayloadExchangeConverter implements PayloadExchangeAu
 			}
 			throw new IllegalArgumentException("Unknown Mime Type " + wellKnownAuthType);
 		}
+		finally {
+			rawAuthentication.release();
+		}
+	}
 
 	private Authentication simple(ByteBuf rawAuthentication) {
 		ByteBuf rawUsername = AuthMetadataCodec.readUsername(rawAuthentication);