Failed tx cost us entire gas allowance, but not transaction fee

[kuoweilai]

Describe the bug
When a tx failed, it took all gas allowance from the wallet, not the transaction fee.

To Reproduce
When you tx accidentally failed (e.g. huge price change made your limit order failed), you would lose entire gas allowance (gas price * gas limit), not just the transaction fee

Expected behavior
We should only lose transaction fee shown in explorer.

Screenshots
https://cronos.crypto.org/explorer/address/0x7FBF20916a966Ce00A1cA00F2E679E2A25B3A719/transactions

[thomas-nguy]

Thank you for the report on the mainnet beta version.

Currently, Cronos mainnet beta uses a standard fixed gas, thus raising gas limits won’t increase the chance that transactions get picked up faster. We suggest users keep the gasLimit setting at their required minimum for now. Additionally, there appear to be issues in the Ethermint library and in the BlockScout explorer. The issue in Ethermint has been resolved (evmos/ethermint#751), but would require a coordinated network upgrade due to a consensus-breaking change: in the meantime, a hotfix release binary contains a gas limit restriction on the Web3 RPC API to reduce the impact (https://github.com/crypto-org-chain/cronos/releases/tag/v0.6.2). The next network upgrade will likely contain the EIP1559-style fee market which will further help to alleviate the gas pricing related issues.
Given the root cause was resolved in Ethermint, this issue can be closed.

If you have further follow ups regarding this issue, feel free to reach out to chain@crypto.org.
Also a friendly reminder that we have dedicated bug bounty programs on HackerOne https://hackerone.com/crypto?type

[kuoweilai]

Yeah, but i think even we don't increase gas limit, we still should only pay those gas we spent right? Also, it shows differently in explorer and it's hard to keep track of everything.

[thomas-nguy]

Yes this is correct, is it due to refund mechanism being ignored when transaction is reverted

The bug has been resolved on Ethermint (evmos/ethermint#751)

[kuoweilai]

@thomas-nguy but after i upgraded to 0.6.2, I think it still have this issue, it still didn't refund.

I lost 0.5CRO at block 186416
https://cronos.crypto.org/explorer/address/0xDe1FD04317492130A9ca13945c078bA3F5A673DC/coin-balances

but i only spent 0.12593CRO
https://cronos.crypto.org/explorer/tx/0xbcf0c0b8356dd19108c530158fe493323f480a3f0590c0e54e4be1b527f2938c/internal-transactions

[thomas-nguy]

Yes, tharsis#751 is not yet effective on mainnet beta yet.

tharsis#751 is a consensus breaking change, so the fix can only be included on major binary release (v0.7.x) and it will also require a coordinated network upgrade.

In the meantime, we did released a hotfix in v0.6.2 to mitigate the issue by rejecting transaction with too high gas limit value (crypto-org-chain/ethermint#12)

[kuoweilai]

@thomas-nguy Understandable. Thank you so much for your hard work.

[weidaxu1988]

@thomas-nguy Thanks for the fix, is there any chance to get those gas back?