Atlas: bubble app error data while preserving 4-byte Atlas selector #500

0x1NotMe · 2025-08-20T00:57:44Z

Summary

Escrow: append underlying app revert payload to Atlas error selectors for PreOps/UserOp/AllocateValue failures, sim and non-sim.
ExecutionEnvironment: include DApp revert payload after its Atlas error selectors for delegatecall/call failures and balanceOf helper; enables nested bubbling.
Atlas._handleErrors: revert with full payload for these selectors (sim + non-sim) so appended app data bubbles while the first 4 bytes stay the Atlas selector.
Test: AtlasErrorBubble.t.sol asserts payload layout on preOps failure.

Rationale

Minimal invasive change: keeps existing selectors and decoding behavior; adds app context to the tail of revert data.
Simulator/clients still match on first 4 bytes; advanced consumers can parse the rest for app-level context.

Notes

Base: atlas-v1.6.3
Branch: feat/atlas-bubble-app-errors
Build/tests: forge build; forge test; new test passes.

…ving 4-byte selector - Escrow: append app revert to PreOpsFail/SimFail, UserOpFail/SimFail, AllocateValueFail/SimFail - Atlas._handleErrors: forward full revert payload for these errors (sim + non-sim) - First 4 bytes remain Atlas error selector to preserve decoding semantics

…or selectors for delegatecall/call failures and helper balanceOf errors

…bbling in preOps failure

…ver balanceOf revert

test/AtlasErrorBubble.t.sol

BenSparksCode · 2025-08-22T17:09:43Z

src/contracts/atlas/Atlas.sol

                assembly {
-                    mstore(0, _errorSwitch)
-                    revert(0, 4)
+                    revert(add(revertData, 32), mload(revertData))


FYI these changes push Atlas over the contract size limit by about 185 bytes. If we go with these changes we will need to lower optimizer_runs to get it back under.

But also try to cut down contract size in the modified areas if possible. There might be a Solady lib function that could do this, not sure

Yeah, there's this helper. We should probably use it once we've build the bytes revertData in each case we want to bubble up

https://github.com/Vectorized/solady/blob/main/src/utils/LibCall.sol#L201

I don't think this would actually reduce contract size but I can add the fix

183 bytes without Solady and 209 bytes over the limit using LibCall.bubbleUpRevert

Oof okay. Was hoping it would reduce code duplication.

src/contracts/common/ExecutionEnvironment.sol

- Replace confusing variable names (_err2 -> _err, _ret -> _returnData) in ExecutionEnvironment.sol - Update test naming convention to follow project standards (test_ErrorHandling_*) - Replace try-catch pattern with low-level call pattern in tests for cleaner code - Remove console.log statements from tests - Add comprehensive test coverage for all error bubbling scenarios: - PreOps failures - UserOp delegatecall and regular call failures - AllocateValue failures - PreSolver and PostSolver failures - Security test for malicious solver error spoofing - Fix test configuration to include proper gas limits for all UserOperations These changes address all feedback from PR #500 while maintaining the core functionality of preserving Atlas error selectors with appended DApp error data. Co-Authored-By: BenSparksCode <noreply@github.com>

BenSparksCode

Even after setting optimizer runs to the lowest (1), Atlas is still 55 bytes over the limit, so I don't think we can merge this change in - no way we can deploy it on most EVM chains without refactoring, or the contract size limit EIP upgrade

0x1NotMe added 3 commits August 20, 2025 09:45

execution env: include underlying DApp revert payload after Atlas err…

7bcaa0e

…or selectors for delegatecall/call failures and helper balanceOf errors

test: assert Atlas revert payload preserves selector and app error bu…

71d4a92

…bbling in preOps failure

0x1NotMe requested a review from BenSparksCode August 20, 2025 00:58

refactor(execution env): reuse single error variable for pre/post sol…

b06c22b

…ver balanceOf revert

0x1NotMe requested a review from thogard785 August 20, 2025 01:14