pico-quorum

Running the GS021 reproduction

repro.mjs shows Safe{Wallet}’s GS021 with a contract-owner confirmation, and the fix, on your own machine. It needs about ten seconds and no keys or funds. Everything happens on a local Anvil fork of Base Sepolia, with throwaway keys, and nothing is sent to a real chain.

What you need

• Node 20 or newer. Check with node --version.
• Foundry, for anvil. Check with ~/.foundry/bin/anvil --version, which should say 1.8.3. If it’s missing: curl -L https://foundry.paradigm.xyz | sh, then ~/.foundry/bin/foundryup -i v1.8.3.
  • The installer doesn’t add Foundry to your PATH, so either use the full path as below, or run export PATH="$HOME/.foundry/bin:$PATH" in each terminal (or add it to ~/.zshrc).
• Internet, for the fork’s first reads from https://sepolia.base.org.

Run it

Terminal 1: the fork. Leave it running.

~/.foundry/bin/anvil --fork-url https://sepolia.base.org --port 8547

It prints a banner and ends with Listening on 127.0.0.1:8547. Its test accounts aren’t used.

Terminal 2: the reproduction.

cd ~/git/pico-quorum/docs/upstream/safe-wallet-gs021/repro
npm ci            # first time only: viem, @noble/curves and @safe-global/protocol-kit at the locked versions
node repro.mjs

What you should see

fork of Base Sepolia at http://127.0.0.1:8547, block 47298253

2-of-2 EOA + passkey: Safe 1.5.0, 2-of-2; confirmations sorted by owner: EOA, contract
  current (createExistingTx) 450 bytes -> reverts GS021
  fixed (toSafeSignature)    450 bytes -> simulation OK
  executed with the fixed layout: ExecutionSuccess true, recipient +1000000000000 wei, logged signatures = fixed: true

3-of-3 passkey + EOA + passkey: Safe 1.5.0, 3-of-3; confirmations sorted by owner: contract, EOA, contract
  current (createExistingTx) 835 bytes -> reverts GS021
  fixed (toSafeSignature)    835 bytes -> simulation OK
  executed with the fixed layout: ExecutionSuccess true, recipient +1000000000000 wei, logged signatures = fixed: true

1-of-2 control: Safe 1.5.0, 1-of-2; confirmations sorted by owner: contract, EOA
  current (createExistingTx) 450 bytes -> simulation OK
  fixed (toSafeSignature)    450 bytes -> simulation OK
  executed with the fixed layout: ExecutionSuccess true, recipient +1000000000000 wei, logged signatures = fixed: true

Only the block number changes from run to run. How to read each line:

• current (createExistingTx) is the signatures laid out the way Safe{Wallet} does today: every confirmation added as a plain signature. With a threshold of 2 or 3, the Safe rejects them with GS021.
• fixed (toSafeSignature) is the same confirmations with the contract one added as a contract signature, the PR’s fix. The simulation passes.
• executed with the fixed layout is the real execTransaction on the fork, checked three ways:
  • the Safe emitted ExecutionSuccess
  • the recipient received the 0.000001 ETH
  • the signature bytes the Safe logged are exactly the fixed layout
• The 1-of-2 control passes both ways, because a threshold of 1 only checks the first 65-byte slot. So the failure depends on a threshold of 2 or more.

More

• Run it again: node repro.mjs restores the fork when it finishes, so it can run any number of times on the same anvil. Ctrl-C in terminal 1 stops the fork, and nothing is left behind.
• Regenerate the unit-test fixtures: node repro.mjs --fixture also prints a FIXTURE {...} line. The keys come from fixed seeds and the signatures are deterministic, so it matches the patch’s test data byte for byte.
• Another RPC: anvil --fork-url <your Base Sepolia RPC> --port 8547. If the fork runs somewhere else, use node repro.mjs --rpc http://127.0.0.1:<port>.

If something goes wrong:

• ECONNREFUSED 127.0.0.1:8547: anvil isn’t running, or it’s on another port.
• HTTP 429 from anvil: the public RPC is rate-limiting. Wait a moment, or use your own RPC.
• createProxyWithNonce reverted: an older copy of the script ran on this fork without cleaning up. Restart anvil.