Erroneous handling of `record_external_operation` error return

CVE-2024-21629

What is CVE-2024-21629?

Rust EVM is an Ethereum Virtual Machine interpreter. In rust-evm, a feature called record_external_operation was introduced, allowing library users to record custom gas changes. This feature can have some bogus interactions with the call stack. In particular, during finalization of a CREATE or CREATE2, in the case that the substack execution happens successfully, rust-evm will first commit the substate, and then call record_external_operation(Write(out_code.len())). If record_external_operation later fails, this error is returned to the parent call stack, instead of Succeeded. Yet, the substate commitment already happened. This causes smart contracts able to commit state changes, when the parent caller contract receives zero address (which usually indicates that the execution has failed). This issue only impacts library users with custom record_external_operation that returns errors. The issue is patched in release 0.41.1. No known workarounds are available.

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