DDOS attack base on _nextOrderId value can be set MAX by attacker lead to other customers can't create a new sell_order

Description

• The _nextOrderId was set uint256 sizes,can be controlled the by seller when they try to create a new sell order,but the source codes didn't check the value of _nextOrderId,so when the value was added to 2^256 - 1, the value of _nextOrderId will overflow,but on Solidity ^0.8.0 will prevent overflow from happening and stop the code from running by throwing an exception that createSellOrder function will not running successful forever.

  uint256 orderId = _nextOrderId++;
  
  

• Other bug is the nextOrderId++ was running before transfer that attacker can maliciously accumulate _nextOrderId values ​​through unsuccessful transactions to make DDOS attacks more rapid.

  uint256 orderId = _nextOrderId++;

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  IERC20(_tokenToSell).safeTransferFrom(msg.sender, address(this), _amountToSell);

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Impact:

• DDOS attack

Proof of Concept

Recommended Mitigation