ETH transfers fail due to incorrect receiver dust balance handling

[sekisamu]

Issue: Bug in eth-decimals - ETH transfers fail due to incorrect receiver dust balance handling

Context

During the migration of Uniswap V2 periphery, ETH transfer operations were initially failing due to precision conversion issues between ETH and DOT. Values smaller than 1,000,000 couldn't be converted to native balance, resulting in DecimalPrecisionLoss errors. This issue was addressed in paritytech/polkadot-sdk#9101.

Problem Description

After applying the fix from #9101, ETH transfer operations still fail during v2-periphery testing.

Steps to Reproduce

1. Clone the repository

git clone https://github.com/papermoonio/v2-periphery-polkadot
cd v2-periphery-polkadot
pnpm install

2. Add .env file
   Create a .env file in the project root:

LOCAL_PRIV_KEY=0x5fb92d6e98884f76de468fa3f6278f8807c48bebc13595d45af5bdc4da702133
AH_PRIV_KEY=0xxx

3. Run the test

USE_POLKAVM=true npx hardhat test ./test/UniswapV2Router01.spec.ts --network local --grep 'swapExactTokensForETH'

Error Messages

Hardhat reports two types of errors:

1. Revert error:

1) UniswapV2Router{01,02}
     UniswapV2Router02
       swapExactTokensForETH
         happy path123:
   Error: execution reverted: "TransferHelper::safeTransferETH: ETH transfer failed" (action="estimateGas", data="0x08c379a0000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000345472616e7366657248656c7065723a3a736166655472616e736665724554483a20455448207472616e73666572206661696c6564000000000000000000000000", reason="TransferHelper::safeTransferETH: ETH transfer failed", transaction={ "data": "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", "from": "0xf24FF3a9CF04c71Dbc94D0b566f7A27B94566cac", "to": "0x7b21801C4B7219BDeb3494AC98e948abBD25b2e9" }, invocation=null, revert={ "args": [ "TransferHelper::safeTransferETH: ETH transfer failed" ], "name": "Error", "signature": "Error(string)" }, code=CALL_EXCEPTION, version=6.14.3)

2. Panic error:

2) UniswapV2Router{01,02}
     UniswapV2Router02
       swapExactTokensForETH
         amounts:
   ProviderError: execution reverted: panic: assertion failed (0x01)

Investigation

Detailed investigation of the substrate node logs reveals a suspicious error (both hardhat errors stem from this underlying issue):

TRACE tokio-runtime-worker runtime::revive::strace: call(flags_and_callee: 34359935664, ref_time_limit: 18446744073709551615, proof_size_limit: 18446744073709551615, deposit_and_value: 18446159137818405824, input_data: 133232, output_data: 18446158996084753072) = Ok(TransferFailed) gas_consumed: Weight { ref_time: 22257362352, proof_size: 1049891 }

Root Cause

After reviewing the code in paritytech/polkadot-sdk#9101, I've identified a bug in the handling of the receiver's dust balance.

Impact

• All ETH transfer operations fail
• Uniswap V2 and other DeFi protocols cannot function properly
• Any contract relying on ETH transfers is affected

[marian-radu]

The issue appears to be fixed in the latest version: polkadot-weekly2025w38-rc3. The tests are passing when run against a node running the asset-hub-westend-runtime.

However, transient issues were observed when running the tests against revive-dev-node. These issues seem to be related to the configuration of the revive-dev-node.

[pgherveou]

seems to be running well now on my PC (linux)

[pgherveou]

will test on mac but closing for now