Merge pull request #18184 from hakman/azure-nil-pointer

azure: Fix possible nil pointer dereferences

Author: k8s-ci-robot

pkg/resources/azure/azure.go

@@ -409,7 +409,9 @@ func (g *resourceGetter) listVMScaleSetsAndRoleAssignments(ctx context.Context)
 		}
 		rs = append(rs, r)
 
-		principalIDs[*vmss.Identity.PrincipalID] = vmss
+		if vmss.Identity != nil && vmss.Identity.PrincipalID != nil {
+			principalIDs[*vmss.Identity.PrincipalID] = vmss
+		}
 	}
 
 	resourceGroupRAs, err := g.listRoleAssignments(ctx, principalIDs, g.resourceGroupID())
@@ -445,8 +447,17 @@ func (g *resourceGetter) toVMScaleSetResource(vmss *compute.VirtualMachineScaleS
 	subnets := set.New[string]()
 	asgs := set.New[string]()
 	lbs := set.New[string]()
+	if vmss.Properties == nil || vmss.Properties.VirtualMachineProfile == nil || vmss.Properties.VirtualMachineProfile.NetworkProfile == nil {
+		return nil, fmt.Errorf("VMSS %s has no network profile", fi.ValueOf(vmss.Name))
+	}
 	for _, iface := range vmss.Properties.VirtualMachineProfile.NetworkProfile.NetworkInterfaceConfigurations {
+		if iface.Properties == nil {
+			continue
+		}
 		for _, ip := range iface.Properties.IPConfigurations {
+			if ip.Properties == nil || ip.Properties.Subnet == nil {
+				continue
+			}
 			subnet, err := arm.ParseResourceID(*ip.Properties.Subnet.ID)
 			if err != nil {
 				return nil, err

upup/pkg/fi/cloudup/azuretasks/vmscaleset.go

@@ -175,9 +175,12 @@ func (s *VMScaleSet) Find(c *fi.CloudupContext) (*VMScaleSet, error) {
 		return nil, fmt.Errorf("expecting exactly 1 SSH key for %q, found %d: %+v", *s.Name, len(sshKeys), sshKeys)
 	}
 
-	userData, err := base64.StdEncoding.DecodeString(*profile.UserData)
-	if err != nil {
-		return nil, fmt.Errorf("failed to decode user data: %w", err)
+	var userData []byte
+	if profile.UserData != nil {
+		userData, err = base64.StdEncoding.DecodeString(*profile.UserData)
+		if err != nil {
+			return nil, fmt.Errorf("failed to decode user data: %w", err)
+		}
 	}
 
 	vmss := &VMScaleSet{
@@ -196,14 +199,18 @@ func (s *VMScaleSet) Find(c *fi.CloudupContext) (*VMScaleSet, error) {
 			VirtualMachineScaleSetStorageProfile: profile.StorageProfile,
 		},
 		RequirePublicIP:    to.Ptr(ipConfig.Properties.PublicIPAddressConfiguration != nil),
-		SKUName:            found.SKU.Name,
-		Capacity:           found.SKU.Capacity,
 		ComputerNamePrefix: osProfile.ComputerNamePrefix,
 		AdminUser:          osProfile.AdminUsername,
 		SSHPublicKey:       sshKeys[0].KeyData,
 		UserData:           fi.NewBytesResource(userData),
 		Tags:               found.Tags,
-		PrincipalID:        found.Identity.PrincipalID,
+	}
+	if found.SKU != nil {
+		vmss.SKUName = found.SKU.Name
+		vmss.Capacity = found.SKU.Capacity
+	}
+	if found.Identity != nil {
+		vmss.PrincipalID = found.Identity.PrincipalID
 	}
 	if ipConfig.Properties != nil && ipConfig.Properties.ApplicationSecurityGroups != nil {
 		for _, asg := range ipConfig.Properties.ApplicationSecurityGroups {
@@ -220,7 +227,9 @@ func (s *VMScaleSet) Find(c *fi.CloudupContext) (*VMScaleSet, error) {
 	if found.Zones != nil {
 		vmss.Zones = found.Zones
 	}
-	s.PrincipalID = found.Identity.PrincipalID
+	if found.Identity != nil {
+		s.PrincipalID = found.Identity.PrincipalID
+	}
 	return vmss, nil
 }
 
@@ -380,6 +389,8 @@ func (s *VMScaleSet) RenderAzure(t *azure.AzureAPITarget, a, e, changes *VMScale
 	if err != nil {
 		return err
 	}
-	e.PrincipalID = result.Identity.PrincipalID
+	if result.Identity != nil {
+		e.PrincipalID = result.Identity.PrincipalID
+	}
 	return nil
 }