Address chainsecurity #1 comment

[cwang25]

Reference:

1. Function saveCode has an else branch that should not be executed as stated in the inline note. However, an attacker can trigger the conditions that saveCode() always enters in the else branch for any code. This can be achieved by sending some Ether (e.g., 1 wei) to the precomputed address of the script, which changes the codehash of the address from 0 to the one corresponding to an EOA. Once this happen, there is no way for the system to deploy the same code anymore. Hence, one could use this attack vector to prevent deploying any new scripts (e.g., frontrunning, or precomputing addresses if the script code is public before deployment), or triggering selfdestruc for scripts that do delegatecalls.

Fixes:

• Remove CodeHashMismatch
• CodeJar will now always deploy/override if the codehash mismatch on the destination address

[kevincheng96]

LGTM!