First element in the Array will be left out in for loop operation

[c4-bot-9]

Lines of code

https://github.com/code-423n4/2024-07-reserve/blob/3f133997e186465f4904553b0f8e86ecb7bbacbf/contracts/libraries/Array.sol#L9-L17

Vulnerability details

Impact

In the ArrayLib::allUnique() the first for loop iterates from 1 but its limit is set less than the array Length which makes it not reach all the elements in the array provided, this can cause the return bool to be incorrect.

Proof of Concept

In the ArrayLib::allUnique() we have this

...
>        for (uint256 i = 1; i < arrLen; ++i) {
            for (uint256 j = 0; j < i; ++j) {
...

Lets assume the array given to this function has a length of 15 the first for function will start from 1 and end at 14 because of the condition i < arrLen, making the number of items looped over 14 instead of 15

Tools Used

manual review

Recommended Mitigation Steps

    function allUnique(IERC20[] memory arr) internal pure returns (bool) {
        uint256 arrLen = arr.length;
-        for (uint256 i = 1; i < arrLen; ++i) {
+        for (uint256 i = 0; i < arrLen; ++i) {
            for (uint256 j = 0; j < i; ++j) {
                if (arr[i] == arr[j]) return false;
            }
        }
        return true;
    }

Assessed type

Loop

[c4-bot-7]

Withdrawn by 4B