lxd/storage/backend_lxd: Ensure new images have a volatile.UUID

Signed-off-by: Julian Pelizäus <julian.pelizaeus@canonical.com>

lxd/storage/backend_lxd.go

@@ -3598,12 +3598,16 @@ func (b *lxdBackend) EnsureImage(fingerprint string, op *operations.Operation) e
 				return err
 			}
 
-			// Reset img volume variables as we just deleted the old one.
+			// Reset img volume as we just deleted the old one.
 			imgDBVol = nil
-			imgVol = b.GetVolume(drivers.VolumeTypeImage, contentType, fingerprint, nil)
 		}
 	}
 
+	if imgDBVol == nil {
+		// Instantiate a new volume including its own UUID.
+		imgVol = b.GetNewVolume(drivers.VolumeTypeImage, contentType, fingerprint, nil)
+	}
+
 	// Check if we already have a suitable volume on storage device.
 	volExists, err := b.driver.HasVolume(imgVol)
 	if err != nil {