IllegalReferenceCountException in HttpPostMultipartRequestDecoder.

Netty version

4.1.22.Final

JVM version (e.g. java -version)

1.8.0_162

OS version (e.g. uname -a)

windows 10

The error is observed in versions 4.1.20-4.1.22

HttpPostRequestDecoder decoder = new HttpPostRequestDecoder(request);
try {
...
} finally {
	decoder.destroy();
}

When you call decoder.destroy () MixedAttribute.release () for objects is performed 2 times.

PostTest.zip

io.netty.util.IllegalReferenceCountException: refCnt: 0, increment: 1
    	at io.netty.util.AbstractReferenceCounted.release0(AbstractReferenceCounted.java:87)
    	at io.netty.util.AbstractReferenceCounted.release(AbstractReferenceCounted.java:71)
    	at io.netty.handler.codec.http.multipart.MixedAttribute.release(MixedAttribute.java:320)
    	at io.netty.handler.codec.http.multipart.HttpPostMultipartRequestDecoder.destroy(HttpPostMultipartRequestDecoder.java:947)
    	at io.netty.handler.codec.http.multipart.HttpPostRequestDecoder.destroy(HttpPostRequestDecoder.java:247)

[danielflower]

I’m also not calling HttpData.release() so for now I’m using this workaround:

multipartRequestDecoder.getBodyHttpDatas().clear();
multipartRequestDecoder.destroy();

Maybe this is related to the unusual way I’m creating the decoder, which is to construct it from a stream (because of reasons).

multipartRequestDecoder = new HttpPostMultipartRequestDecoder(request);
byte[] buffer = new byte[16 * 1024];
int read;
while ((read = inputStream.read(buffer)) > -1) {
    if (read > 0) {
        ByteBuf content = Unpooled.copiedBuffer(buffer, 0, read);
        multipartRequestDecoder.offer(new DefaultHttpContent(content));
    }
}
multipartRequestDecoder.offer(new DefaultLastHttpContent());

[normanmaurer]

I think this should be fixed now… please reopen if you still see the issue once you upgraded to latest version