TensorFlow vulnerable to `CHECK` failures in `UnbatchGradOp`

ImpactThe UnbatchGradOp function takes an argument id that is assumed to be a scalar. A nonscalar id can trigger a CHECK failure and crash the program.pythonimport numpy as npimport tensorflow as tf id is not scalartf.rawops.UnbatchGradoriginalinput= tf.constant1,batchindex=tf.constant0,0,0 , ,...