fix: enforce balance-delta accounting in StandardBridge#296
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Fee-on-transfer and rebasing tokens are documented as unsupported, but `_initiateBridgeERC20` credited `deposits[_localToken][_remoteToken]` and forwarded `_amount` to the remote bridge without checking that the escrow balance actually increased by `_amount`. With a fee-on-transfer token this leaves the local escrow short while the full `_amount` is minted/released on the remote chain, eventually breaking withdrawals. Take the balance before and after `safeTransferFrom` and require the delta to equal `_amount`. Unsupported tokens now revert at deposit time (fail closed) rather than silently underfunding the bridge. Bump L1StandardBridge to 2.9.0 and L2StandardBridge to 1.14.0 and regenerate snapshots/semver-lock.json.
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Summary
Closes #289.
StandardBridge._initiateBridgeERC20crediteddeposits[_localToken][_remoteToken]and forwarded_amountto the remote bridge without verifying that the escrow balance actually increased by_amount. Fee-on-transfer and rebasing tokens are documented as unsupported, but they were still accepted permissionlessly — leaving the local escrow short while the full_amountis minted/released on the remote chain, eventually breaking withdrawals once the escrow is drained.This PR measures the bridge's balance before and after
safeTransferFromand requires the delta to equal_amount. Unsupported tokens now revert at deposit time (fail closed) rather than silently underfunding the bridge.src/universal/StandardBridge.sol: balance-delta check aroundsafeTransferFromsrc/L1/L1StandardBridge.sol: semver bump 2.8.0 → 2.9.0src/L2/L2StandardBridge.sol: semver bump 1.13.0 → 1.14.0snapshots/semver-lock.json: regeneratedTest plan
forge test --match-contract "L1StandardBridge|L2StandardBridge|StandardBridge"— 59 passed, 0 failedforge build --forcecleanjust semver-lockregenerated