From 67d2585ec0e24a0b59d1d5db0804faf04ac3f128 Mon Sep 17 00:00:00 2001 From: Justin Date: Thu, 13 Jun 2019 21:01:10 +0100 Subject: [PATCH] Fix #1173 The bug is that it's possible to include a participating validator which has custody bit one *without* specifying that validator in `attestation.aggregation_bitfield`. In other words, we want to check that every bit in `custody_bitfield` is zero whenever the corresponding bit in `aggregation_bitfield` is zero. Well spotted @protolambda --- specs/core/0_beacon-chain.md | 1 + 1 file changed, 1 insertion(+) diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md index 86df18898..0725f5211 100644 --- a/specs/core/0_beacon-chain.md +++ b/specs/core/0_beacon-chain.md @@ -991,6 +991,7 @@ def convert_to_indexed(state: BeaconState, attestation: Attestation) -> IndexedA """ attesting_indices = get_attesting_indices(state, attestation.data, attestation.aggregation_bitfield) custody_bit_1_indices = get_attesting_indices(state, attestation.data, attestation.custody_bitfield) + assert set(custody_bit_1_indices).issubset(attesting_indices) custody_bit_0_indices = [index for index in attesting_indices if index not in custody_bit_1_indices] return IndexedAttestation(