Kicking players for a too large payload can't be canceled

[Timongcraft]

Bungeecord version

git:BungeeCord-Bootstrap:1.20-R.02-SNAPSHOT:94ea027:1726 by md_5

Server version

git-Paper-169 (MC: 1.20.1) (Implementing API version 1.20.1-R0.1-SNAPSHOT) (Git: b4e3b3d)

Client version

1.20.1

Bungeecord plugins

none

The bug

If you send large packets you get a exception that "the payload is too large" and get kicked. Which in my opinion should just be managed by plugins and/or controlled by a config value.

Log output (links)

07:28:04 [WARNING] [Timongcraft] -> UpstreamBridge - could not decode packet! java.lang.IllegalArgumentException: Payload too large
07:28:04 [INFO] [Timongcraft] disconnected with: DecoderException : java.lang.IllegalArgumentException: Payload too large @ io.netty.handler.codec.MessageToMessageDecoder:98
07:28:04 [INFO] [Timongcraft] -> UpstreamBridge has disconnected

Checking

• [X] I am using BungeeCord and not a fork. Issues with forks should not be reported here.
• [X] I think this is not an issue with a bungeecord plugin.
• [ ] I have not read these checkboxes and therefore I just ticked them all.
• [X] This is not a question or plugin creation help request.

[Janmm14]

We are just enforcing vanilla protocol limits for the plugin message packet size.

Can you name any reasons on why you need this changed?

[Timongcraft]

E.g. the Axiom Mod (https://axiom.moulberry.com) with the Plugin (https://github.com/Moulberry/AxiomPaperPlugin) is a very useful building mod which sends large custom packets.

[Outfluencer]

They should fix it in my opinion, its not a bungee issue

[Outfluencer]

If you could cancel the kick the packet would still not be read to the end and would get dropped

[Timongcraft]

But why? It works for example with velocity, so why should't it with bungeecord?

[Moulberry]

I agree that it's not a bungeecord issue, but it's not so easy to fix on my end.

To clear up some confusion, the Paper plugin supports the increased packet size, so the 'vanilla limit' is being bypassed on Paper's side. It's just BungeeCord that won't let the packet through to Paper.

The mod & plugin supports changing the packet size limit here from 0x100000 to Short.MAX_VALUE, which would solve the disconnect on BungeeCord's side.

However, doing so will result in extreme performance degradation due to the large number of packets and reduced compressability of a 32k buffer compared to a 1mb buffer.

As the original poster said, a reasonable middle-ground would be to introduce a config option to change these limits. If this is an acceptable solution, I'd be happy to submit a pull request to this project.

Thanks, Moulberry

[Janmm14]

I would prefer not making this a regular config option.

I suggest bungee doing one of these things:

• Extract constant to static field so plugins can edit easier(still without guarantees on api)
• Create hidden config option
• Use system property