Undefined behavior in `SparseTensorSliceDataset`
### Impact
The implementation of `SparseTensorSliceDataset`
https://github.com/tensorflow/tensorflow/blob/5100e359aef5c8021f2e71c7b986420b85ce7b3d/tensorflow/core/kernels/data/sparse_tensor_slice_dataset_op.cc#L227-L292 has an undefined behavior: under certain condition it can be made to dereference a `nullptr` value:
```python
import tensorflow as tf
import numpy as np
tf.raw_ops.SparseTensorSliceDataset(
indices=[[]],
values=[],
dense_shape=[1,1])
```
The 3 input arguments represent a sparse tensor. However, there are some preconditions that these arguments must satisfy but these are not validated in the implementation.
### Patches
We have patched the issue in GitHub commit 965b97e4a9650495cda5a8c210ef6684b4b9eceb
https://github.com/tensorflow/tensorflow/commit/965b97e4a9650495cda5a8c210ef6684b4b9eceb.
The fix will be included in TensorFlow 2.8.0. We will also cherrypick this commit on TensorFlow 2.7.1, TensorFlow 2.6.3, and TensorFlow 2.5.3, as these are also affected and still in supported range.
### For more information
Please consult our security guide
https://github.com/tensorflow/tensorflow/blob/master/SECURITY.md for more information regarding the security model and how to contact us with issues and questions.
### Attribution
This vulnerability has been reported by Faysal Hossain Shezan from University of Virginia.