deepcopy original before upgradeClientSideFieldManager, as original and target share the same object, and calling Get() on original will change target, and cause target patch data to carry unwanted data loaded from live resource

Signed-off-by: wallyatgithub <30530146+wallyatgithub@users.noreply.github.com>

pkg/kube/client.go

@@ -736,7 +736,10 @@ func (c *Client) Update(originals, targets ResourceList, options ...ClientUpdate
 					slog.String("gvk", target.Mapping.GroupVersionKind.String()))
 
 				if updateOptions.upgradeClientSideFieldManager {
-					patched, err := upgradeClientSideFieldManager(original, updateOptions.dryRun, updateOptions.fieldValidationDirective)
+					// target and original shares same Object, deep copy original to avoid changing target
+					copiedOriginal := *original
+					copiedOriginal.Object = original.Object.DeepCopyObject()
+					patched, err := upgradeClientSideFieldManager(&copiedOriginal, updateOptions.dryRun, updateOptions.fieldValidationDirective)
 					if err != nil {
 						slog.Debug("Error patching resource to replace CSA field management", slog.Any("error", err))
 						return err