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noeleon930/re-entrancy

Created October 22, 2016 05:55
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re-entrancy
pragma solidity ^0.4.0;
// THIS CONTRACT CONTAINS A BUG - DO NOT USE
contract Fund {
/// Mapping of ether shares of the contract.
mapping(address => uint) shares;
/// Withdraw your share.
function withdraw() {
if (msg.sender.send(shares[msg.sender]))
shares[msg.sender] = 0;
}
}
contract Fund2 {
/// Mapping of ether shares of the contract.
mapping(address => uint) shares;
/// Withdraw your share.
function withdraw() {
var share = shares[msg.sender];
shares[msg.sender] = 0;
if (!msg.sender.send(share))
throw;
}
}
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noeleon930 commented Mar 20, 2017 

contract Attacker {
    function() {
        // 使執行一直被卡在第9行，造成遞迴
        msg.sender.call("withdraw");
    }
}

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