Co-op server crash: "Server fatal crash: SZ_GetSpace: 5712 is > full buffer size"

[Teflon1]

I was playing on Mara's co-op server when the server crashed on E2M3c with the error "Server fatal crash: SZ_GetSpace: 5712 is > full buffer size".

Background info:

• The crash happened while one player was moving around the basement. I was in the pool in the basement that leads to the secret Poseidon's Trident, so I couldn't see for sure, but it sounded like he was still in the basement because of how close his sounds were. The last player, I believe, had not moved from spawn yet.

• At the start of E2M3c, we somehow got warped back to E2M3b as soon as the server loaded. Then, we walked back to E2M3b's exit (after everyone spawned in again) and returned to E2M3c. E2M3c played smoothly until the server crash.

• People were on the server for at least an hour. The players managed to beat all of Episode 1 and got up to E2M3c. Most of Episode 1 had been beaten by the time I joined, so I can't estimate the time for sure.

• All of us were using DK_EXE_122015, the latest build.

Below is a video that starts from combat at end of E2M3b, the warparound from E2M3c to E2M3b, then back to E2M3c, and ends at the server crash.

https://www.youtube.com/watch?v=FARLveVn3Aw

[Teflon1]

Updating formatting.

[Frank Sapone]

It appears my packet compression for the large packet overflows seem to have failed for some reason. That's also a very large buffer size. Either way, do you have a demo file of it? Maybe I can test it out that way and see what the packet sizes were.

[Teflon1]

I don't have a demo of this. I was recording directly with Bandicam.

[Frank Sapone]

The more I think about this... was anyone cheating with noclip? I do notice that noclipping around maps can cause large packets. Either way, the max getspace size for packets under multiplayer currently is 2800. So something... maybe walking into a large area with a bunch of enemies at the same time or noclipping around and looking out into a large area could have caused the packet size to be greater than 2800 for that particular frame.

[Frank Sapone]

Can't reproduce, no new info. And even if there was new info we can't do anything with it. Maybe we'll see it again (hopefully not).

[Frank Sapone]

Figured out what this was as we were able to reliably trigger this bug when we were having problems with teleporters and large DM matches.