Undefined Geometry nodes cause a crash when connected to a Group Output node #89004

New Issue

Fen · 2021-06-09T17:20:47+02:00

Fen commented

2021-06-09 17:20:47 +02:00

System Information
Operating system: Linux-5.8.0-55-generic-x86_64-with-glibc2.31 64 Bits
Graphics card: Quadro K1000M/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 390.143

Blender Version
Broken: version: 2.93.0, branch: master, commit date: 2021-06-02 11:21, hash: 84da05a8b8
Worked: Also crashes in 2.92

Short description of error
Undefined geometry nodes cause a crash when they are plugged into a Group Output node, either indirectly or directly.

Exact steps for others to reproduce the error

Load the attached file in Blender 2.9.3
Go into the Geometry Nodes tab
Plug the Undefined node into the Group Output node's "Geometry" input
Crash

To produce an Undefined node, you can create a Material Assign node in Blender 3.0.0a.

The crash also occurs if you plug the Undefined node into something else, and then plug that node's geometry output into the Group Output node.

If the nodes were connected in the file, then Blender crashes immediately when you try to load it.

Stacktrace: crash-test.crash.txt

Test File:
crash-test.blend

**System Information** Operating system: Linux-5.8.0-55-generic-x86_64-with-glibc2.31 64 Bits Graphics card: Quadro K1000M/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 390.143 **Blender Version** Broken: version: 2.93.0, branch: master, commit date: 2021-06-02 11:21, hash: `84da05a8b8` Worked: Also crashes in 2.92 **Short description of error** Undefined geometry nodes cause a crash when they are plugged into a Group Output node, either indirectly or directly. **Exact steps for others to reproduce the error** 1. Load the attached file in Blender 2.9.3 2. Go into the *Geometry Nodes* tab 3. Plug the *Undefined* node into the *Group Output* node's "Geometry" input 4. Crash To produce an *Undefined* node, you can create a *Material Assign* node in Blender 3.0.0a. The crash also occurs if you plug the *Undefined* node into something else, and then plug *that* node's geometry output into the *Group Output* node. If the nodes were connected in the file, then Blender crashes immediately when you try to load it. Stacktrace: [crash-test.crash.txt](https://archive.blender.org/developer/F10164432/crash-test.crash.txt) Test File: [crash-test.blend](https://archive.blender.org/developer/F10164428/crash-test.blend)

Fen commented

2021-06-09 17:20:47 +02:00

Added subscriber: @chemicalcrux

blender-admin commented

2021-06-09 17:20:47 +02:00

#88685 was marked as duplicate of this issue

Leon Zandman commented

2021-06-09 17:34:16 +02:00

Added subscriber: @Zandman

Leon Zandman commented

2021-06-09 17:34:16 +02:00

Confirmed on macOS Big Sur M1 with the official 2.93.0 release.

To produce an Undefined node, you can create a Material Assign node in Blender 3.0.0a.

So you're using a 3.0.0 feature in 2.93.0? Maybe that shouldn't be supported? I don't think Blender should crash, though. Maybe refuse to load the newer Blend.

Confirmed on macOS Big Sur M1 with the official 2.93.0 release. > To produce an Undefined node, you can create a Material Assign node in Blender 3.0.0a. So you're using a 3.0.0 feature in 2.93.0? Maybe that shouldn't be supported? I don't think Blender should crash, though. Maybe refuse to load the newer Blend.

Fen commented

2021-06-09 17:40:26 +02:00

It's not really a new feature; it's just a node that Blender doesn't know about. I would expect the same to happen after removing an add-on that introduced new nodes (not sure if that's possible though :p )

It already handles this by showing an Undefined node. It just needs to not crash when that node is connected to an output.

I see a commit that talks about preventing a crash with undefined nodes, so perhaps there was a regression?

https://developer.blender.org/rBSc5569ba140382015c32bd638532097ea05168607

It's not really a new *feature*; it's just a node that Blender doesn't know about. I would expect the same to happen after removing an add-on that introduced new nodes (not sure if that's possible though :p ) It already handles this by showing an *Undefined* node. It just needs to not crash when that node is connected to an output. ![image.png](https://archive.blender.org/developer/F10164461/image.png) I see a commit that talks about preventing a crash with undefined nodes, so perhaps there was a regression? https://developer.blender.org/rBSc5569ba140382015c32bd638532097ea05168607

Pratik Borhade commented

2021-06-09 19:51:55 +02:00

Added subscriber: @PratikPB2123

Pratik Borhade commented

2021-06-09 19:51:55 +02:00

Changed status from 'Needs Triage' to: 'Needs Developer To Reproduce'

Pratik Borhade commented

2021-06-09 19:51:55 +02:00

Not sure if this report will be considered as a bug or else. Better to wait for other developer's or triager's reply :)

Fen commented

2021-06-09 22:23:28 +02:00

I tested this out with a freshly-compiled copy of Blender by hex-editing the .blend file so that the node name was bogus. It does not crash. 2.93 crashes on the same file. You can try it out yourself here:

crash-test.blend

The geometry node modifier has gotten a significant rewrite between blender-v2.93-release and the current master, judging by a casual diffing.

So, whatever the problem was is already gone from 3.0.0, but it's still alive in 2.9.3. Since I'm not really aware of people hot-swapping geometry nodes, this might be minor enough to just ignore (:

I tested this out with a freshly-compiled copy of Blender by hex-editing the .blend file so that the node name was bogus. It does not crash. 2.93 crashes on the same file. You can try it out yourself here: [crash-test.blend](https://archive.blender.org/developer/F10164730/crash-test.blend) The geometry node modifier has gotten a significant rewrite between `blender-v2.93-release` and the current `master`, judging by a casual diffing. So, whatever the problem was is already gone from 3.0.0, but it's still alive in 2.9.3. Since I'm not really aware of people hot-swapping geometry nodes, this might be minor enough to just ignore (:

Jacques Lucke commented

2021-06-10 16:07:57 +02:00

Added subscribers: @Jeroen-Bakker, @JacquesLucke

Jacques Lucke commented

2021-06-10 16:07:57 +02:00

Changed status from 'Needs Developer To Reproduce' to: 'Confirmed'

Jacques Lucke self-assigned this 2021-06-10 16:07:57 +02:00

Jacques Lucke commented

2021-06-10 16:07:57 +02:00

@Jeroen-Bakker here is a relatively straight forward patch that fixes this in blender-v2.93-release: P2167. It just disables geometry nodes when there are undefined nodes or sockets. While I want to commit the changes that are not in MOD_nodes.cc in master as well, the fix is not necessary there. The new evaluator in master should handle this case more gracefully. Can you commit this in the release branch or should I do it?

Just FYI, the problem here is not actually that there is an undefined node, but that there is an undefined socket type (the material socket).

@Jeroen-Bakker here is a relatively straight forward patch that fixes this in `blender-v2.93-release`: [P2167](https://archive.blender.org/developer/P2167.txt). It just disables geometry nodes when there are undefined nodes or sockets. While I want to commit the changes that are not in `MOD_nodes.cc` in `master` as well, the fix is not necessary there. The new evaluator in master should handle this case more gracefully. Can you commit this in the release branch or should I do it? Just FYI, the problem here is not actually that there is an undefined node, but that there is an undefined socket type (the material socket).

Fen commented

2021-06-10 16:11:09 +02:00

Ah, good catch. I didn't think of that. Thanks for having a look!