lemonmon - overview, withdrawals: DepositFeed does not exist

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lemonmon

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overview, withdrawals: DepositFeed does not exist

Summary

There is no DepositFeed contract. The implementation of Deposit contract would be OptimismPortal.
There are some multiple occasions of incorrect information, for example, stating that Optimism Portal inherits from DepositFeed contract.

Also, using "Deposit Contract" and DepositFeed contract interchangeably may confuse the reader.

Vulnerability Detail

https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/overview.md?plain=1#L52

There is no DepositFeed contract. It should be OptimismPortal contract.

 - The `OptimismPortal` contract emits `TransactionDeposited` events, which the rollup driver reads in order to process 

https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/overview.md?plain=1#L109

Here as well, the DepositFeed contract should be OptimismPortal contract.

call the `depositTransaction` method on the `OptimismPortal` contract. This in turn emits `TransactionDeposited` events, 

https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/overview.md?plain=1#L144

Here as well, the DepositFeed contract should be OptimismPortal contract.

deposits initiated via the `OptimismPortal` contract on L1. All L2 blocks can also contain _sequenced transactions_, i.e.

https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/withdrawals.md?plain=1#L133-L135

The OptimismPortal inherits Initializable, ResourceMetering and Semver and there is no DepositFeed contract in the inheritance tree.

Impact

Factually wrong specs

Code Snippet

https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/overview.md?plain=1#L52
https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/overview.md?plain=1#L109
https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/overview.md?plain=1#L144
https://github.com/sherlock-audit/2023-01-optimism/blob/main/optimism/specs/withdrawals.md?plain=1#L133-L135

Tool used

Manual Review

Recommendation

Use "Deposit Contract" or OptimismPortal depending on the context, instead of DepositFeed contract.