fix(protocol): check 63/64 gasleft() not smaller than specified gaslimit

[dantaik]

See code-423n4/2024-03-taiko-findings#180

[openzeppelin-code]

fix(protocol): check 63/64 gasleft() not smaller than specified gaslimit

Generated at commit: bbf6e1c9b7ce4066f0bb164b2a208e583cc6e585

🚨 Report Summary

	Severity Level	Results
Contracts	Critical High Medium Low Note Total	2 2 0 3 39 46
Dependencies	Critical High Medium Low Note Total	0 0 0 0 0 0

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[Brechtpd]

Ah this discussion, I remember it still from the Loopring smart wallet days! For me this is still a UI issue because the gas limit can simply be 1/64 higher to avoid it if it would ever be a problem. But the check is valid, just depends on what you expect the smart contract to check and I think this check goes pretty far because the gas limit is already just an abstract number for users.

[dantaik]

Simplified the changes:

• We only check gasleft()*64/64 >= gasLimit when processMessage is called by someone other than the owner. In all other cases (including recall the message), failure due to gas will not cause any issue for the msg owner.
• No extra gas addition is applied to the above check (as in the Loopring code), if after the external call, the tx failed due to out-of-gas, the whole transaction will revert so no harm will be done to the msg.owner as well.