DOESN'T CHECK FOR RETURN VALUE OF TRANSFERFROM()

[code423n4]

Lines of code

https://github.com/code-423n4/2022-09-y2k-finance/blob/main/src/Vault.sol#L167

Vulnerability details

Impact

In function deposit(), it doesnot check the return value of transferFrom() that helps in transfer of share(assets share) from user to Vault contract,
and furthere this deposit() mints share to user in return

Proof of Concept

For example :

. let a User call deposit() of Vault contract
. now assume if transfer of asset from user to vault fails, so transferFrom() returns false
. then as no check present
. deposit() mints some share to user considering that user sent some assets to vault, where actually transfer call was failed
. User can take advantage of this and mint share repeated for him

    function deposit( uint256 id, uint256 assets, address receiver )
    public
    override
    marketExists(id)
    epochHasNotStarted(id)
    nonReentrant
    returns (uint256 shares)
{
    // Check for rounding error since we round down in previewDeposit.
    require((shares = previewDeposit(id, assets)) != 0, "ZeroValue");

    asset.transferFrom(msg.sender, address(this), shares);  // @audit -- bool return check absent

    _mint(receiver, id, shares, EMPTY);   

    emit Deposit(msg.sender, receiver, id, shares, shares);

    return shares;
} 

Tools Used

Manual Review

Recommended Mitigation Steps

There should be a check for return value of transferFrom(), if it fails then whole function should revert.

    function deposit( uint256 id, uint256 assets, address receiver )
    public
    override
    marketExists(id)
    epochHasNotStarted(id)
    nonReentrant
    returns (uint256 shares)
{
    // Check for rounding error since we round down in previewDeposit.
    require((shares = previewDeposit(id, assets)) != 0, "ZeroValue");

    bool succ = asset.transferFrom(msg.sender, address(this), shares); 
    require(succ, "Asset tranfer failed");

    _mint(receiver, id, shares, EMPTY);   // @audit -- safeMint should use

    emit Deposit(msg.sender, receiver, id, shares, shares);

    return shares;
}

[HickupHH3]

dup #499