Bug description

When executing the opcode 0x0a EXP, SealEVM will wait forever without outputting result.

Source

Check the implementation in SealEVM at:

https://github.com/SealSC/SealEVM/blob/1ee9b6d4149aa32d3d079a1b0e6dc9f71f60700c/instructions/arithmetic.go#L176-L194

and in the function Exp implementation at:

https://github.com/SealSC/SealEVM/blob/1ee9b6d4149aa32d3d079a1b0e6dc9f71f60700c/evmInt256/evmInt256.go#L213-L216

It seems that the execution of this line fails:

    i.Int.Exp(i.Int, e.Int, nil)

How to reproduce

Set deployed bytecode

Simply pull the latest version of the SealEVM and enter the example dir.

git clone https://github.com/SealSC/SealEVM.git
cd example

Change the var deployCode in example/code.go to bytecode 6ce1fd12a42ec6dc66e9702e565a6f6ed801f2f2984c5805d1b92423f24d720a60005260406000f3

 var deployCode, _ = hex.DecodeString("6ce1fd12a42ec6dc66e9702e565a6f6ed801f2f2984c5805d1b92423f24d720a60005260406000f3")

Where 6ce1fd12a42ec6dc66e9702e565a6f6ed801f2f2984c5805d1b92423f24d720a60005260406000f3 are the opcodes as shown below:

PUSH13 e1fd12a42ec6dc66e9702e565a
PUSH16 6ed801f2f2984c5805d1b92423f24d72
EXP
PUSH1 00
MSTORE
PUSH1 40
PUSH1 00
RETURN

Result

cd example
go build -o sealevm
./sealevm

You can see that the SealEVM stucks and return nothing .

alleysira@LAPTOP-GOVN7GRV:~/poc-sealevm/SealEVM/example$ go build -o sealevm
alleysira@LAPTOP-GOVN7GRV:~/poc-sealevm/SealEVM/example$ ./sealevm

But if I change the module in Exp() in evmInt256.go to another number, for example:

    i.Int.Exp(i.Int, e.Int, e.Int)

The opcode EXP can be executed successfully.

alleysira@LAPTOP-GOVN7GRV:~/poc-sealevm/SealEVM/example$ ./sealevm
counter:
counter:

Here is the result from geth/evm 1.14.9-unstable-6eb42a6b-20240815. Geth and other EVM returned 0.

// geth
{"pc":0,"op":108,"gas":"0xffffff","gasCost":"0x3","memSize":0,"stack":[],"depth":1,"refund":0,"opName":"PUSH13"}
{"pc":14,"op":111,"gas":"0xfffffc","gasCost":"0x3","memSize":0,"stack":["0xe1fd12a42ec6dc66e9702e565a"],"depth":1,"refund":0,"opName":"PUSH16"}
{"pc":31,"op":10,"gas":"0xfffff9","gasCost":"0x294","memSize":0,"stack":["0xe1fd12a42ec6dc66e9702e565a","0x6ed801f2f2984c5805d1b92423f24d72"],"depth":1,"refund":0,"opName":"EXP"}
{"pc":32,"op":96,"gas":"0xfffd65","gasCost":"0x3","memSize":0,"stack":["0x0"],"depth":1,"refund":0,"opName":"PUSH1"}
{"pc":34,"op":82,"gas":"0xfffd62","gasCost":"0x6","memSize":0,"stack":["0x0","0x0"],"depth":1,"refund":0,"opName":"MSTORE"}
{"pc":35,"op":96,"gas":"0xfffd5c","gasCost":"0x3","memory":"0x0000000000000000000000000000000000000000000000000000000000000000","memSize":32,"stack":[],"depth":1,"refund":0,"opName":"PUSH1"}
{"pc":37,"op":96,"gas":"0xfffd59","gasCost":"0x3","memory":"0x0000000000000000000000000000000000000000000000000000000000000000","memSize":32,"stack":["0x40"],"depth":1,"refund":0,"opName":"PUSH1"}
{"pc":39,"op":243,"gas":"0xfffd56","gasCost":"0x3","memory":"0x0000000000000000000000000000000000000000000000000000000000000000","memSize":32,"stack":["0x40","0x0"],"depth":1,"refund":0,"opName":"RETURN"}
{"output":"00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","gasUsed":"0x2ac"}

// SealEVM 
{"pc":0,"op":108,"gas":"0xfffffc","gasCost":"0x3","memory":"0x","stack":null,"opName":"PUSH13"}
{"pc":14,"op":111,"gas":"0xfffff9","gasCost":"0x3","memory":"0x","stack":["0xe1fd12a42ec6dc66e9702e565a"],"opName":"PUSH16"}
{"pc":31,"op":10,"gas":"0xffffef","gasCost":"0xa","memory":"0x","stack":["0xe1fd12a42ec6dc66e9702e565a","0x6ed801f2f2984c5805d1b92423f24d72"],"opName":"EXP"}

SealSC / SealEVM

The `EXP` opcode in SealEVM causes the EVM execution to hang #31

Bug description

Source

How to reproduce

Set deployed bytecode

Result