[Bug]: When creating a Linux VMSS, if not providing “sourceImageReference”, a panic is created

[chkp-orhaz]

Is there an existing issue for this?

• I have searched the existing issues

Affected Resource(s)

provider-azure-compute - LinuxVirtualMachineScaleSet

Resource MRs required to reproduce the bug

apiVersion: compute.azure.upbound.io/v1beta2
kind: LinuxVirtualMachineScaleSet
metadata:
name: vmsstest

spec:
providerConfigRef:
name: cool-provider
forProvider:
location: Australia East
resourceGroupName: aue-rg
adminUsername: notused
networkInterface:
- name: eth0
osDisk:
caching: ReadWrite
storageAccountType: Premium_LRS
diskSizeGb: 100
sku: Standard_D4ds_v5

Steps to Reproduce

1. Apply the manifest without SourceImageReference
2. Look into the resource (get LinuxVirtualMachineScaleSet vmsstest -oyaml)
   a panic will be seen "runtime error: index out of range [0] with length 0"
3. Look into the provider pod (kubectl logs provider-azure-compute-as5d64sa4da-asd4as5dsa4-das4as)

What happened?

Instead of throwing an error saying hi, SourceImageReference is missing, it appears that a panic has occured

Relevant Error Output Snippet

github.com/hashicorp/terraform-provider-azurerm/internal/services/compute.expandSourceImageReferenceVMSS({0x15776900?, 0xc4c9a25?, 0xc50eb79?}, {0x0?, 0x5?})
	github.com/hashicorp/[email protected]/internal/services/compute/shared_schema.go:706 +0x5c5
github.com/hashicorp/terraform-provider-azurerm/internal/services/compute.resourceLinuxVirtualMachineScaleSetCreate(0xc006ac1580, {0xaae1160, 0xc006960008})
	github.com/hashicorp/[email protected]/internal/services/compute/linux_virtual_machine_scale_set_resource.go:122 +0xb4d
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*Resource).create(0xd291740?, {0xd291740?, 0xc0015f0e00?}, 0xd?, {0xaae1160?, 0xc006960008?})
	github.com/hashicorp/terraform-plugin-sdk/[email protected]/helper/schema/resource.go:766 +0x15f
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*Resource).Apply(0xc000b2aee0, {0xd291740, 0xc0015f0e00}, 0x0, 0xc0063d3000, {0xaae1160, 0xc006960008})
	github.com/hashicorp/terraform-plugin-sdk/[email protected]/helper/schema/resource.go:909 +0xa69
github.com/crossplane/upjet/pkg/controller.(*terraformPluginSDKExternal).Create(0xc0025c69a0, {0xd291740, 0xc0015f0e00}, {0xd306ec0, 0xc006103508})
	github.com/crossplane/[email protected]/pkg/controller/external_tfpluginsdk.go:592 +0xdd
github.com/crossplane/upjet/pkg/controller.(*terraformPluginSDKAsyncExternal).Create.func1()
	github.com/crossplane/[email protected]/pkg/controller/external_async_tfpluginsdk.go:166 +0x1d7
created by github.com/crossplane/upjet/pkg/controller.(*terraformPluginSDKAsyncExternal).Create in goroutine 5621
	github.com/crossplane/[email protected]/pkg/controller/external_async_tfpluginsdk.go:145 +0x14c
E1231 14:43:04.012765       1 runtime.go:79] Observed a panic: runtime.boundsError{x:0, y:0, signed:true, code:0x0} (runtime error: index out of range [0] with length 0)

Crossplane Version

1.15.0

Provider Version

v1.0.1 - v1.10.2 tested

Kubernetes Version

v1.27.9

Kubernetes Distribution

AKS

Additional Info

No response