vsphere-iso: resource pool path handling can panic or fail with malformed lookup path

[bertfranken420]

Upstream Issue Draft: packer-plugin-vsphere Resource Pool Path/Panic

Title

vsphere-iso: resource pool path handling can panic or fail with malformed lookup path

Repository

hashicorp/packer-plugin-vsphere

Version/Environment

• Packer: 1.15.0
• Plugin: github.com/hashicorp/vsphere 2.1.1
• vCenter: 7.0.3
• Builder: vsphere-iso

Problem Summary

When resource_pool is provided as a full inventory path (or contains slashes), pool lookup can be malformed and later fail/panic at VM create.

Observed symptoms:

• malformed path shape in logs like:
  • vSAN Cluster 1/Resources//Datacenter /host/vSAN 1/vSAN Cluster 1/Resources
• failure around Creating virtual machine...
• in some runs: plugin crash / unexpected EOF

Repro (high level)

1. Configure vsphere-iso with resource_pool set to absolute inventory path:
   • /Datacenter/host/vSAN 1/vSAN Cluster 1/Resources
2. Run packer build.
3. Observe failure in resource pool resolution / VM create phase.

Expected

resource_pool handling should:

• accept absolute inventory paths as-is
• accept slash-containing paths as-is
• only prefix relative pool names with <cluster>/Resources/...
• fail with explicit error if default pool cannot be resolved
• avoid nil pool flow that can cascade into panic

Suggested Fix Area

• builder/vsphere/driver/resource_pool.go
• function FindResourcePool(...)

Suggested Logic

• TrimSpace on input.
• If empty:
  • try <cluster>/Resources
  • fallback DefaultResourcePool
  • return explicit error if unresolved.
• If starts with /: resolve as absolute path (with trimmed fallback).
• If contains /: resolve directly as provided path.
• Else: treat as relative name under <cluster>/Resources/<name>.
• Guard against nil pool before returning.

Patch Validation

After patch:

• no malformed doubled-path behavior
• no panic at create phase from nil/invalid pool resolution
• run advances to:
  • Creating virtual machine...
  • Powering on virtual machine...
  • Typing boot command...

Additional Note

If build later fails at timeout waiting for IP, that is guest installer/network/tools path, not this resource-pool resolution bug.

[tenthirtyam]

@bertfranken420, please edit or reopen the issue using the provided issue form.

Additionally, please reproduce on vSphere 8.0 or later; 7.0 is no longer actively supported by the project.

Reference: CONTRIBUTING.md