Holograph contest - JC's results

L-01 Unused receive() function will lock Ether in contract

If the intention is for the Ether to be used, the function should call another function, otherwise it should revert

8 instances in 8 files:

https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/Holographer.sol#L124

https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L152

https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L863

https://github.com/code-423n4/2022-10-holograph/blob/main/src/module/LayerZeroModule.sol#L317

https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC20H.sol#L113

https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC721H.sol#L113

https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographBridge.sol#L478

https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L1110

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Summary

• G-01 Multiple address mappings can be combined into a single mapping of an address to a struct (8 instances)
• G-02 <x> += <y> costs more gas than <x> = <x> + <y> for state variables (9 instances)
• G-03 Empty blocks should be removed or emit something (12 instances)
• G-04 Use custom errors rather than revert()/require() strings to save deployment gas (97 instances)
• G-05 Use calldata instead of memory for function parameters (34 instances)

Total: 160 instances in 5 issues

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G-01 Multiple address mappings can be combined into a single mapping of an address to a struct

Multiple address mappings can be combined into a single mapping of an address to a struct, where appropriate saves a storage slot for the mapping. Depending on the circumstances and sizes of types, can avoid a Gsset (20000 gas) per mapping combined. Reads and subsequent writes can also be cheaper when a function requires both values and they both fit in the same storage slot.

8 instances in 3 files:

HolographERC20.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L57 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L62 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L87

HolographERC721.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L91 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L97

HolographOperator.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L119 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L124 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L129

G-02 <x> += <y> costs more gas than <x> = <x> + <y> for state variables

9 instances in 3 files:

HolographFactory.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographFactory.sol#L229

HolographERC20.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L586 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L587 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L603

HolographOperator.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L283 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L339 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L735 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L1077 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L1078

G-03 Empty blocks should be removed or emit something

The code should be refactored such that they no longer exist, or the block should do something useful, such as emitting an event or reverting. If the contract is meant to be extended, the contract should be abstract and the function signatures be added without any default implementation. If the block is an empty if-statement block to avoid doing subsequent checks in the else-if/else conditions, the else-if/else conditions should be nested under the negation of the if-statement, because they involve different classes of checks, which may lead to the introduction of errors when the code is later modified (if(x){}else if(y){...}else{...} => if(!x){if(y){...}else{...}})

12 instances in 10 files:

HolographFactory.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographFactory.sol#L37

Holographer.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/Holographer.sol#L41

PA1D.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L67

HolographERC20.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L112

HolographERC721.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L132

LayerZeroModule.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/module/LayerZeroModule.sol#L52

ERC20H.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC20H.sol#L34 https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC20H.sol#L113

ERC721H.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC721H.sol#L34 https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC721H.sol#L113

HolographBridge.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographBridge.sol#L56

HolographOperator.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L134

G-04 Use custom errors rather than revert()/require() strings to save deployment gas

Custom errors are available from solidity version 0.8.4. The instances below match or exceed that version.

97 instances in 10 files:

HolographFactory.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographFactory.sol#L45 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographFactory.sol#L121 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographFactory.sol#L129 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographFactory.sol#L155

Holographer.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/Holographer.sol#L49 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/Holographer.sol#L67

PA1D.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L75 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L91 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L291 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L312 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L317 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L336 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L340 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L361 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L373 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L378

HolographERC20.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L120 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L142 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L266 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L288 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L328 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L353 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L383 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L406 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L430 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L500 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L521 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L522 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L528 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L530 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L546 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L596 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L597 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L599

HolographERC721.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L159 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L164 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L224 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L271 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L272 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L289 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L305 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L309 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L320 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L321 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L322 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L359 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L370 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L414 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L523 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L540 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L590 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L601 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L630 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L658 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L663 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L668 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L716 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L717 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L718 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L719 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L770 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L771 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L807

LayerZeroModule.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/module/LayerZeroModule.sol#L60 https://github.com/code-423n4/2022-10-holograph/blob/main/src/module/LayerZeroModule.sol#L136

ERC20H.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC20H.sol#L18 https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC20H.sol#L24 https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC20H.sol#L26 https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC20H.sol#L48

ERC721H.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC721H.sol#L18 https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC721H.sol#L24 https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC721H.sol#L26 https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC721H.sol#L48

HolographBridge.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographBridge.sol#L64 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographBridge.sol#L106 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographBridge.sol#L128 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographBridge.sol#L158

HolographOperator.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L142 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L210 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L251 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L255 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L269 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L316 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L347 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L386 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L492 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L496 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L629 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L657 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L730 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L740 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L758 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L782 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L790 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L804 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L812 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L833

G-05 Use calldata instead of memory for function parameters

Having function arguments use calldata instead of memory can save gas.

Recommended Mitigation Steps: Change function arguments from memory to calldata.

34 instances in 10 files:

HolographFactory.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographFactory.sol#L44 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographFactory.sol#L94 https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographFactory.sol#L95

Holographer.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/Holographer.sol#L50

PA1D.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L74 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L86 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L266 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L273 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L284 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L285 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L307 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L308 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L327 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L328 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L329 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L353 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L372 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L389 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L418 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/PA1D.sol#L584

HolographERC20.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L119 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L400 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L425 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC20.sol#L542

HolographERC721.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L139 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L357 https://github.com/code-423n4/2022-10-holograph/blob/main/src/enforcer/HolographERC721.sol#L521

LayerZeroModule.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/module/LayerZeroModule.sol#L59

ERC20H.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC20H.sol#L41 https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC20H.sol#L46

ERC721H.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC721H.sol#L41 https://github.com/code-423n4/2022-10-holograph/blob/main/src/abstract/ERC721H.sol#L46

HolographBridge.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographBridge.sol#L63

HolographOperator.sol https://github.com/code-423n4/2022-10-holograph/blob/main/src/HolographOperator.sol#L141