BugBusters - Potential Precision Loss in poolBorrow function

[sherlock-admin]

BugBusters

high

Potential Precision Loss in poolBorrow function

Summary

The function poolBorrow may suffer from potential precision loss due to the order of operations in the line uint256 usedQuota = record.amount.div(oldInterestIndex).mul(currentInterestIndex);. The division operation is performed before the multiplication, which can result in the truncation of decimal values and a loss of precision.

Vulnerability Detail

The issue arises from performing division before multiplication in the line record.amount.div(oldInterestIndex).mul(currentInterestIndex). When dividing two integers in Solidity, the result is truncated towards zero, discarding any decimal portion. Subsequently, multiplying the truncated result by currentInterestIndex can further amplify the precision loss introduced by the division operation.

Impact

The precision loss can lead to inaccurate calculations and unintended results.

Code Snippet

https://github.com/sherlock-audit/2023-06-dodo/blob/main/new-dodo-v3/contracts/DODOV3MM/D3Vault/D3VaultFunding.sol#L70-L92

Tool used

Manual Review

Recommendation

To avoid potential precision loss, it is recommended to rearrange the operations and perform multiplication before division. The revised line of code should be:

uint256 usedQuota = record.amount.mul(currentInterestIndex).div(oldInterestIndex);

Duplicate of #45