CVE-2021-41213: TensorFlow deadlock in tf.function with mutually recursive functions

Summary

TensorFlow's `tf.function` API can deadlock when two `tf.function`-decorated Python functions are mutually recursive, because the code uses a non-reentrant `Lock` object. Loading any model that contains such mutually recursive functions is vulnerable. An attacker can cause denial of service by getting users to load such a model and call a recursive `tf.function`, though this is not a frequent scenario.

Mitigation

The fix will be included in TensorFlow 2.7.0. The commit will also be cherry-picked to TensorFlow 2.6.1, TensorFlow 2.5.2, and TensorFlow 2.4.4.

Affected packages in the Exposure Registry

Matched by package name and ecosystem. Each entry shows whether the package delegates to a language model and how many tracked packages depend on it.

• tensorflowPyPINo LLM dependency detected · 26 tracked dependents
• tensorflow-gpuPyPINo LLM dependency detected · 2 tracked dependents

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