Steps to Reproduce a major crash caused by Network Physics Weirdness and Humanoid Animation or Layered Clothing

Info

System: Windows 10 - 64bit
Studio Version: Version 0.614.0.6140412 (64bit)

Description

The client crashes, but not only the client, other players can crash as well. This is caused by strange things that I am not really sure about, I just have the steps that lead to the crash very very often.
Happens on both Client and Studio, it’s Engine related.

I encountered this issue first in a game, but it doesn’t matter. I’ve extracted everything I needed from that game to crash the game.

It involves strange Network Ownership behavior, Humanoid Animation going weird, Character Apperance modification and Layered Clothing.

I made a video, it explains everything.

Expected Result

No crash.

Actual Result

It crashes.

Sidenotes, while I was recording I managed to error out the new ui idk

if you want the videos of that on where it happens, lemme know

All the log/dump files, reproduction steps/place file, videos can be found here:
https://devforum.roblox.com/t/crash-files-for-the-bug-report/2874075

1 Like

When your roblox client crashes, is the crash related to a Nullpointerexception?
If so please let me know, because I have made a game, which doesn’t crash at a low playercount rate, but at a playercount of 50 a few players crash infrequently, including me.
I decrypted the dmp file and found out that the crash was related to a Nullpointerexception, and I really want to make sure that it is not because of a memory leak (I already checked every single line of code and could not find a single one).

One of the crash dumps talks about a thread.

0xc0000005
The thread tried to read from or write to a virtual address for which it does not have the appropriate access.

That wasn’t the only exception type that I found.

The .dmp file alone is useless without the .pdb. There’s some info inside of it though, but idk what to do with it. One of them had LeftFoot.LeftFoot but there’s no LeftFoot under a LeftFoot on a regular R15, so it made no sense.

The screenshot that somehow remained left over in this report, is a totally different issue.

 

I can generate a crash file for this issue within seconds and setup an entire crash analytics farm, with me just alone on a server, Studio or Client. This crash issue that I am after, might be related to crashes I’ve encountered once but never knew what it was, also other players can crash as well due to it, so it’s not entirely client-side.

And I really wanna know the cause of this crash.

 

 

Decrypt how?

There is a program in the Microsoft store called “WinDbg”, which somehow manages to analyze dmp files and makes them readable, though it only shows windows related exceptions rather than why the crash got triggered. It’s very hard determining what is causing the crash and this is very annoying.
I also had the error “0xc0000005” but the cause for the error was “NULL_CLASS_PTR_READ_AVRF” which usually means that there was a Nullpointerexception.
Hopefully any stuff member will adress you with the issue

I put the .dmp files in Visual Studio :person_shrugging:

OH LOL why didn’t I think about that. Anyways, the issue now also occurs inside roblox studio for me, but now very frequently.
image

What is your cause?

My cause involves… well, I used something from a different game where I encountered the issue and constructed it together.

It involves Client and Server side difference with physics and assemblies. Then it involves Anchoring the HumanoidRootPart, which changes the NetworkOwnership obviously, and then in involved changing the HumanoidDescription.

Between this weirdness there’s another step. A step that works only because the assembly is different in client and server side stuff. It freezes the player and freezes the player’s animation in a weird way. Once you have “destroyed” the Character’s Animation, the crash can occur.

Thanks for the report! We’ll investigate.

Its hard to determine, but I found out the crash used to happen because of the bulletholes not disappearing, but the crash in the screenshot happened before shooting any wheapon. It looks like a physics replication bug to me

Please, let me know the cause if it gets figured out. I am very interested