# #41952 \[SC-Insight] Reduce storage costs by eliminating stakedTimes in StakeV2::startUnstake

**Submitted on Mar 19th 2025 at 15:17:42 UTC by @Ragnarok for** [**Audit Comp | Yeet**](https://immunefi.com/audit-competition/audit-comp-yeet)

* **Report ID:** #41952
* **Report Type:** Smart Contract
* **Report severity:** Insight
* **Target:** <https://github.com/immunefi-team/audit-comp-yeet/blob/main/src/StakeV2.sol>
* **Impacts:**

## Description

## Description

In the `StakeV2::startUnstake` function, `stakedTimes[msg.sender]` is used to limit the number of times a user can initiate an unstake. However, instead of maintaining a separate counter, we can use `vestings[msg.sender].length` to enforce this restriction.

By doing so, we eliminate an unnecessary `SSTORE` operation (used to update `stakedTimes[msg.sender]`), which can help reduce gas costs.

`StakeV2::startUnstake` function:

```solidity
function startUnstake(uint256 unStakeAmount) external {
    require(unStakeAmount > 0, "Amount must be greater than 0");
=>  require(stakedTimes[msg.sender] < STAKING_LIMIT, "Amount must be less then the STAKING_LIMIT constant"); 
    ...
    vestings[msg.sender].push(Vesting(unStakeAmount, start, end));
=>  stakedTimes[msg.sender]++;
    emit VestingStarted(msg.sender, unStakeAmount, vestings[msg.sender].length - 1);
}
```

## Recommendation

Modify the `StakeV2::startUnstake` function:

```solidity
function startUnstake(uint256 unStakeAmount) external {
    require(unStakeAmount > 0, "Amount must be greater than 0");
=>  require(vestings[msg.sender].length < STAKING_LIMIT, "Amount must be less then the STAKING_LIMIT constant"); 
    ...
    vestings[msg.sender].push(Vesting(unStakeAmount, start, end));
=>  // Delete this line
    emit VestingStarted(msg.sender, unStakeAmount, vestings[msg.sender].length - 1);
}
```

Modify the `StakeV2::_unstake` function:

```solidity
function _unstake(uint256 index) private {
    Vesting memory vesting = vestings[msg.sender][index];
    (uint256 unlockedAmount, uint256 lockedAmount) = calculateVesting(vesting);
    require(unlockedAmount != 0, "No unlocked amount");

    _remove(msg.sender, index);
    if (lockedAmount > 0) {
        emit RageQuit(msg.sender, unlockedAmount, lockedAmount, index);
    } else {
        emit Unstake(msg.sender, unlockedAmount, index);
    }
=>  stakedTimes[msg.sender]--; // Delete this line
}
```

## Proof of Concept

## Proof of Concept

Modify the `StakeV2::startUnstake` function:

```solidity
function startUnstake(uint256 unStakeAmount) external {
    require(unStakeAmount > 0, "Amount must be greater than 0");
=>  require(vestings[msg.sender].length < STAKING_LIMIT, "Amount must be less then the STAKING_LIMIT constant"); 
    ...
    vestings[msg.sender].push(Vesting(unStakeAmount, start, end));
=>  // Delete this line
    emit VestingStarted(msg.sender, unStakeAmount, vestings[msg.sender].length - 1);
}
```

Modify the `StakeV2::_unstake` function:

```solidity
function _unstake(uint256 index) private {
    Vesting memory vesting = vestings[msg.sender][index];
    (uint256 unlockedAmount, uint256 lockedAmount) = calculateVesting(vesting);
    require(unlockedAmount != 0, "No unlocked amount");

    _remove(msg.sender, index);
    if (lockedAmount > 0) {
        emit RageQuit(msg.sender, unlockedAmount, lockedAmount, index);
    } else {
        emit Unstake(msg.sender, unlockedAmount, index);
    }
=>  stakedTimes[msg.sender]--; // Delete this line
}
```


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://reports.immunefi.com/yeet/41952-sc-insight-reduce-storage-costs-by-eliminating-stakedtimes-in-stakev2-startunstake.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.