"data out-of-bounds" error when parse transaction log

[I-Lotus]

Ethers Version

5.7.1

Search Terms

No response

Describe the Problem

I have unexpected error when try to parse log which actually is TransferBatch event from Ethereum Goerli blockchain. I get an error data out-of-bounds (length=0, offset=32, code=BUFFER_OVERRUN, version=abi/5.7.0). I don't know actually it is bug of library or something wrong with log but Ethereum Goerli etherscan can parse it https://goerli.etherscan.io/tx/0x8553e3c03549563cb47ca1c30fcab2a6bea929b19622d6163fdb66b03b53920e

Code Snippet

const { ethers } = require("ethers");

const logJson = `{
    "transactionIndex": 12,
    "blockNumber": 7918462,
    "transactionHash": "0x8553e3c03549563cb47ca1c30fcab2a6bea929b19622d6163fdb66b03b53920e",
    "address": "0x3996002cea99bc220f992e4c868702a5ba60bd26",
    "topics": [
        "0x4a39dc06d4c0dbc64b70af90fd698a233a518aa5d07e595d983b8c0526c8f7fb",
        "0x0000000000000000000000001c08d194d547a56aa6a20f2c90818b954cda2054",
        "0x0000000000000000000000000000000000000000000000000000000000000000",
        "0x000000000000000000000000e2fbb99ddb441a822b047c518d7d697eea8d5274"
    ],
    "data": "0x00000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000002",
    "logIndex": 9,
    "blockHash": "0xd2fc8b49be3587306e7e2789b29376dcab6ddd0857949ce3396dcf49134f17ae",
    "timestamp": 1667952300
}`;

const log = JSON.parse(logJson);

const iface = new ethers.utils.Interface(["event TransferBatch(address indexed _operator, address indexed _from, address indexed _to, uint256[] _ids, uint256[] _values)"]);
const parsedLog = iface.parseLog({ topics: log.topics, data: log.data });

Contract ABI

["event TransferBatch(address indexed _operator, address indexed _from, address indexed _to, uint256[] _ids, uint256[] _values)"]

Errors

Error: data out-of-bounds (length=0, offset=32, code=BUFFER_OVERRUN, version=abi/5.7.0)
    at Logger.makeError (/Users/alexeybreez/Projects/mozverse/nft-supernode-api/node_modules/@ethersproject/logger/lib/index.js:238:21)
    at Logger.throwError (/Users/alexeybreez/Projects/mozverse/nft-supernode-api/node_modules/@ethersproject/logger/lib/index.js:247:20)
    at Reader._peekBytes (/Users/alexeybreez/Projects/mozverse/nft-supernode-api/node_modules/@ethersproject/abi/lib/coders/abstract-coder.js:150:24)
    at Reader.readBytes (/Users/alexeybreez/Projects/mozverse/nft-supernode-api/node_modules/@ethersproject/abi/lib/coders/abstract-coder.js:162:26)
    at Reader.readValue (/Users/alexeybreez/Projects/mozverse/nft-supernode-api/node_modules/@ethersproject/abi/lib/coders/abstract-coder.js:168:48)
    at ArrayCoder.decode (/Users/alexeybreez/Projects/mozverse/nft-supernode-api/node_modules/@ethersproject/abi/lib/coders/array.js:214:28)
    at /Users/alexeybreez/Projects/mozverse/nft-supernode-api/node_modules/@ethersproject/abi/lib/coders/array.js:94:31
    at Array.forEach (<anonymous>)
    at unpack (/Users/alexeybreez/Projects/mozverse/nft-supernode-api/node_modules/@ethersproject/abi/lib/coders/array.js:88:12)
    at TupleCoder.decode (/Users/alexeybreez/Projects/mozverse/nft-supernode-api/node_modules/@ethersproject/abi/lib/coders/tuple.js:74:60) {
  reason: 'data out-of-bounds',
  code: 'BUFFER_OVERRUN',
  length: 0,
  offset: 32
}

Environment

node.js (v12 or newer)

Environment (Other)

No response

[ricmoo]

Just by inspection, I can tell the log data is not sufficient for two dynamic-length arrays; each dynamic-length array (the non-indexed parameters) requires 2 words (a pointer, and a length) for a total of 4 words. It looks to be about 2 words.

You should check the contract; maybe they are using asm to emit the log and not computing it correctly. The two words look to encode the values 8 and 2.

[I-Lotus]

Okay, it makes sense. Could you tell me is the any method in ethers.js to check validity of such logs before really do parsing?