test_tstore_rollback_on_failed_create()

Documentation for tests/cancun/eip1153_tstore/test_tstorage_create_contexts.py::test_tstore_rollback_on_failed_create@20373115.

Generate fixtures for these test cases for Amsterdam with:

fill -v tests/cancun/eip1153_tstore/test_tstorage_create_contexts.py::test_tstore_rollback_on_failed_create --fork Amsterdam

Test TSTORE is rolled back after failed CREATE/CREATE2 initcode.

Regression test for #917

Initcode does TLOAD(1) to compute a return size, then does TSTORE(1, 0x6000), then returns data of the computed size. When TLOAD(1) is 0, the return size is 0x600a (exceeds max code size 0x6000), so creation fails.

The caller invokes CREATE/CREATE2 twice with the same initcode. If TSTORE from the first (failed) creation is properly rolled back, the second creation also sees TLOAD(1)==0 and fails the same way. If not rolled back, TLOAD(1)==0x6000 and the second creation succeeds.

Source code in tests/cancun/eip1153_tstore/test_tstorage_create_contexts.py

@pytest.mark.ported_from(
    [
        "https://github.com/holiman/goevmlab/blob/master/examples/tstore_bug-2/main.go",
    ],
)
@pytest.mark.parametrize("create_opcode", [Op.CREATE, Op.CREATE2])
def test_tstore_rollback_on_failed_create(
    state_test: StateTestFiller,
    pre: Alloc,
    create_opcode: Op,
    fork: Fork,
) -> None:
    """
    Test TSTORE is rolled back after failed CREATE/CREATE2 initcode.

    Regression test for
    https://github.com/ethereum/execution-specs/issues/917

    Initcode does TLOAD(1) to compute a return size, then does
    TSTORE(1, 0x6000), then returns data of the computed size.
    When TLOAD(1) is 0, the return size is 0x600a (exceeds max code
    size 0x6000), so creation fails.

    The caller invokes CREATE/CREATE2 twice with the same initcode.
    If TSTORE from the first (failed) creation is properly rolled
    back, the second creation also sees TLOAD(1)==0 and fails the
    same way. If not rolled back, TLOAD(1)==0x6000 and the second
    creation succeeds.
    """
    # Initcode:
    #   return_size = 0x600a - TLOAD(1)
    #   TSTORE(1, 0x6000)
    #   RETURN(offset=0, size=return_size)
    #
    # TLOAD(1)==0:     return_size = 0x600a > max code size -> fail
    # TLOAD(1)==0x6000: return_size = 0x0a <= max code size -> succeed
    max_code_size = fork.max_code_size()

    initcode = (
        Op.TLOAD(1)
        + Op.PUSH4(max_code_size + 0x0A)
        + Op.SUB
        + Op.TSTORE(1, max_code_size)
        + Op.PUSH1(0)
        + Op.RETURN
    )
    initcode_bytes = bytes(initcode)
    initcode_len = len(initcode_bytes)

    caller_code = (
        Om.MSTORE(initcode_bytes, 0)
        + Op.SSTORE(
            0,
            create_opcode(0, 0, initcode_len, 0)
            if create_opcode == Op.CREATE2
            else create_opcode(0, 0, initcode_len),
        )
        + Op.SSTORE(
            1,
            create_opcode(0, 0, initcode_len, 0)
            if create_opcode == Op.CREATE2
            else create_opcode(0, 0, initcode_len),
        )
    )
    caller_address = pre.deploy_contract(caller_code, storage={0: 1, 1: 1})

    sender = pre.fund_eoa()
    tx = Transaction(
        sender=sender,
        to=caller_address,
        gas_limit=16_000_000,
        access_list=[
            AccessList(address=caller_address, storage_keys=[0, 1]),
        ],
    )

    post = {
        # Both creations fail because TSTORE is rolled back;
        # initial storage {0: 1, 1: 1} is overwritten to zeros
        caller_address: Account(storage={0: 0, 1: 0}),
    }

    state_test(pre=pre, post=post, tx=tx)

Parametrized Test Cases

This test generates 2 parametrized test cases across 4 forks.