lemonmon - system_config: incorrect variable name and missing config update type

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lemonmon

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system_config: incorrect variable name and missing config update type

Summary

The specs for system config contains incorrect information and incorrect names for its contents.

1. The names for overhead and scalar are falsely stated as l1FeeOverhead and l1FeeScalar in multiple occasions.
2. The list of the configuration update types is missing the unsafe block signer update

Vulnerability Detail

In the SystemConfig contract, there are public variables overhead and scalar:

https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/packages/contracts-bedrock/contracts/L1/SystemConfig.sol#L51-L59

Below the variables overhead and scalar are incorrectly named as l1FeeOverhead and l1FeeScalar in multiple occasions:

https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/system_config.md?plain=1#L34
https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/system_config.md?plain=1#L73
https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/system_config.md?plain=1#L86-L90

In the above snippet:
Line 89: the names of overhead and scalar
It also is missing the type 3:

• type 3: unsafeBlockSigner overwrite, as address payload.

The corresponding update code snippets from SystemConfig are below:

https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/packages/contracts-bedrock/contracts/L1/SystemConfig.sol#L25-L30
https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/packages/contracts-bedrock/contracts/L1/SystemConfig.sol#L169-L175

Impact

factually incorrect information

• incorrect name of variables
• missing config update type

As the name of variables double as interface to fetch the value, anybody uses the incorrect name in the specs to fetch the values will fail.
Also the specs do not list the possible config update types, so the users may not know that the unsafeBlockSigner can be updated.

Code Snippet

https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/packages/contracts-bedrock/contracts/L1/SystemConfig.sol#L51-L59
https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/system_config.md?plain=1#L34
https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/system_config.md?plain=1#L73
https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/system_config.md?plain=1#L86-L90
https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/packages/contracts-bedrock/contracts/L1/SystemConfig.sol#L25-L30
https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/packages/contracts-bedrock/contracts/L1/SystemConfig.sol#L169-L175

Tool used

Manual Review

Recommendation

Correct the names of the variables and add the missing config update type