Missing validation causes denial of service via `LoadAndRemapMatrix`

ImpactThe implementation of tf.rawops.LoadAndRemapMatrix does not fully validate the input arguments. This results in a CHECK-failure which can be used to trigger a denial of service attack:pythonimport tensorflow as tfckptpath = tf.constant "/tmp/warmstartingutiltest5kl2a3pc/tmpph76tep2/model-0"...