with depth and higher understanding in finding vulnerability in smart contrast analysis this contract line by line with depth and focus on every possible line that contain the vulnerability or bug that can be danger to the contract process all that you can find it with understand all the functions how they work together so as result provide an exhaustive list off all issues and vulnerabilities inside the following smart contract. Be in the issue descriptions and describe the actors involved. Include one exploit scenario in each vulnerability. Output as a valid markdown table with a list of objects that each have ‘description’ ‘action’ ‘severity’ "actors’ ‘scenario’, ‘type’, and ‘line’ columns. ‘type’ can be ‘usability’,
‘vulnerability’, ‘optimization’, or ‘suggestion’. ‘actors’ is a list of the involved actors. ‘severity’ can be ‘low + ice block emoji’,
‘medium’ or ‘high + fire emoji’. ‘line’ is the line number of the issue. Ensure that all fields of the table are filled out. and find the correct vulnerability with real and valid explaining and give all vulnerable lines with code and with details of explaining
HERE is the contract code /*

    Copyright 2020 DODO ZOO.
    SPDX-License-Identifier: Apache-2.0

*/

pragma solidity 0.8.16;

import {DODOMath} from "../../lib/DODOMath.sol";
import {DecimalMath} from "../../lib/DecimalMath.sol";
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import {PMMPricing} from "../../lib/PMMPricing.sol";

/// @notice this contract is used for store state and read state
contract GSPStorage is ReentrancyGuard {

    // ============ Storage for Setup ============
    // _GSP_INITIALIZED_ will be set to true when the init function is called
    bool internal _GSP_INITIALIZED_;
    // GSP does not open TWAP by default
    // _IS_OPEN_TWAP_ can be set to true when the init function is called
    bool public _IS_OPEN_TWAP_ = false;
    
    // ============ Core Address ============
    // _MAINTAINER_ is the maintainer of GSP
    address public _MAINTAINER_;
    // _BASE_TOKEN_ and _QUOTE_TOKEN_ should be ERC20 token
    IERC20 public _BASE_TOKEN_;
    IERC20 public _QUOTE_TOKEN_;
    // _BASE_RESERVE_ and _QUOTE_RESERVE_ are the current reserves of the GSP
    uint112 public _BASE_RESERVE_;
    uint112 public _QUOTE_RESERVE_;
    // _BLOCK_TIMESTAMP_LAST_ is used when calculating TWAP
    uint32 public _BLOCK_TIMESTAMP_LAST_;
    // _BASE_PRICE_CUMULATIVE_LAST_ is used when calculating TWAP
    uint256 public _BASE_PRICE_CUMULATIVE_LAST_;

    // _BASE_TARGET_ and _QUOTE_TARGET_ are recalculated when the pool state changes
    uint112 public _BASE_TARGET_;
    uint112 public _QUOTE_TARGET_;
    // _RState_ is the current R state of the GSP
    uint32 public _RState_;

    // ============ Shares (ERC20) ============
    // symbol is the symbol of the shares
    string public symbol;
    // decimals is the decimals of the shares
    uint8 public decimals;
    // name is the name of the shares
    string public name;
    // totalSupply is the total supply of the shares
    uint256 public totalSupply;
    // _SHARES_ is the mapping from account to share balance, record the share balance of each account
    mapping(address => uint256) internal _SHARES_;
    mapping(address => mapping(address => uint256)) internal _ALLOWED_;

    // ================= Permit ======================

    bytes32 public DOMAIN_SEPARATOR;
    // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    bytes32 public constant PERMIT_TYPEHASH =
        0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
    mapping(address => uint256) public nonces;

    // ============ Variables for Pricing ============
    // _MT_FEE_RATE_ is the fee rate of mt fee
    uint256 public _MT_FEE_RATE_;
    // _LP_FEE_RATE_ is the fee rate of lp fee
    uint256 public _LP_FEE_RATE_;
    uint256 public _K_;
    uint256 public _I_;
    // _PRICE_LIMIT_ is 1/1000 by default, which is used to limit the setting range of I
    uint256 public _PRICE_LIMIT_ = 1e3;

    // ============ Mt Fee ============
    // _MT_FEE_BASE_ represents the mt fee in base token
    uint256 public _MT_FEE_BASE_;
    // _MT_FEE_QUOTE_ represents the mt fee in quote token
    uint256 public _MT_FEE_QUOTE_;

    // ============ Helper Functions ============

    /// @notice Return the PMM state of the pool from inner or outside
    /// @dev B0 and Q0 are calculated in adjustedTarget
    /// @return state The current PMM state
    function getPMMState() public view returns (PMMPricing.PMMState memory state) {
        state.i = _I_;
        state.K = _K_;
        state.B = _BASE_RESERVE_;
        state.Q = _QUOTE_RESERVE_;
        state.B0 = _BASE_TARGET_; // will be calculated in adjustedTarget
        state.Q0 = _QUOTE_TARGET_;
        state.R = PMMPricing.RState(_RState_);
        PMMPricing.adjustedTarget(state);
    }

    /// @notice Return the PMM state variables used for routeHelpers
    /// @return i The price index
    /// @return K The K value
    /// @return B The base token reserve
    /// @return Q The quote token reserve
    /// @return B0 The base token target
    /// @return Q0 The quote token target
    /// @return R The R state of the pool
    function getPMMStateForCall()
        external
        view
        returns (
            uint256 i,
            uint256 K,
            uint256 B,
            uint256 Q,
            uint256 B0,
            uint256 Q0,
            uint256 R
        )
    {
        PMMPricing.PMMState memory state = getPMMState();
        i = state.i;
        K = state.K;
        B = state.B;
        Q = state.Q;
        B0 = state.B0;
        Q0 = state.Q0;
        R = uint256(state.R);
    }

    /// @notice Return the adjusted mid price
    /// @return midPrice The current mid price
    function getMidPrice() public view returns (uint256 midPrice) {
        return PMMPricing.getMidPrice(getPMMState());
    }

    /// @notice Return the total mt fee maintainer can claim
    /// @dev The total mt fee is represented in two types: in base token and in quote token
    /// @return mtFeeBase The total mt fee in base token
    /// @return mtFeeQuote The total mt fee in quote token
    function getMtFeeTotal() public view returns (uint256 mtFeeBase, uint256 mtFeeQuote) {
        mtFeeBase = _MT_FEE_BASE_;
        mtFeeQuote = _MT_FEE_QUOTE_;
    }
}