fix: early return for packing local deposits when EIP-6110 is applied

CHANGELOG.md

@@ -110,6 +110,7 @@ The format is based on Keep a Changelog, and this project adheres to Semantic Ve
 - P2P: Avoid infinite loop when looking for peers in small networks.
 - Fixed another rollback bug due to a context deadline.
 - Fix checkpoint sync bug on holesky. [pr](https://github.com/prysmaticlabs/prysm/pull/14689)
+- Fixed deposit packing for post-Electra: early return if EIP-6110 is applied.
 
 
 ### Security
@@ -1701,7 +1702,7 @@ Aside from the critical fixes for mainnet, this release contains a number of new
 - Use next slot cache for payload attribute
 - Cleanup keymanager mock
 - Update to go 1.20
-- Modify InsertFinalizedDeposits signature to return an error
+  - Modify InsertFinalizedDeposits signature to return an error
 - Improved statefeed initialization
 - Use v1alpha1 server in block production
 - Updated go generated files

beacon-chain/rpc/prysm/v1alpha1/validator/proposer_deposits.go

@@ -94,6 +94,14 @@ func (vs *Server) deposits(
 		return nil, err
 	}
 
+	// In the post-electra phase, this function will usually return an empty list,
+	// as the legacy deposit process is deprecated. (EIP-6110)
+	// NOTE: During the transition period, the legacy deposit process
+	// may still be active and managed. This function handles that scenario.
+	if !isLegacyDepositProcessPeriod(beaconState, canonicalEth1Data) {
+		return []*ethpb.Deposit{}, nil
+	}
+
 	_, genesisEth1Block := vs.Eth1InfoFetcher.GenesisExecutionChainInfo()
 	if genesisEth1Block.Cmp(canonicalEth1DataHeight) == 0 {
 		return []*ethpb.Deposit{}, nil
@@ -277,3 +285,21 @@ func shouldRebuildTrie(totalDepCount, unFinalizedDeps uint64) bool {
 	unFinalizedCompute := unFinalizedDeps * params.BeaconConfig().DepositContractTreeDepth
 	return unFinalizedCompute > totalDepCount
 }
+
+// isLegacyDepositProcessPeriod determines if the current state should use the legacy deposit process.
+func isLegacyDepositProcessPeriod(beaconState state.BeaconState, canonicalEth1Data *ethpb.Eth1Data) bool {
+	// Before the Electra upgrade, always use the legacy deposit process.
+	if beaconState.Version() < version.Electra {
+		return true
+	}
+
+	// Handle the transition period between the legacy and the new deposit process.
+	requestsStartIndex, err := beaconState.DepositRequestsStartIndex()
+	if err != nil {
+		// If we can't get the deposit requests start index,
+		// we should default to the legacy deposit process.
+		return true
+	}
+	eth1DepositIndexLimit := math.Min(canonicalEth1Data.DepositCount, requestsStartIndex)
+	return beaconState.Eth1DepositIndex() < eth1DepositIndexLimit
+}

beacon-chain/rpc/prysm/v1alpha1/validator/proposer_deposits_test.go

@@ -2,12 +2,14 @@ package validator
 
 import (
 	"context"
+	"math"
 	"math/big"
 	"testing"
 
 	mock "github.com/prysmaticlabs/prysm/v5/beacon-chain/blockchain/testing"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache/depositsnapshot"
 	mockExecution "github.com/prysmaticlabs/prysm/v5/beacon-chain/execution/testing"
+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
 	state_native "github.com/prysmaticlabs/prysm/v5/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v5/config/params"
 	"github.com/prysmaticlabs/prysm/v5/container/trie"
@@ -212,3 +214,85 @@ func TestProposer_PendingDeposits_Electra(t *testing.T) {
 	assert.Equal(t, 0, len(deposits), "Received unexpected number of pending deposits")
 
 }
+
+func TestIsLegacyDepositProcessPeriod(t *testing.T) {
+	tests := []struct {
+		name              string
+		state             state.BeaconState
+		canonicalEth1Data *ethpb.Eth1Data
+		want              bool
+	}{
+		{
+			name: "pre-electra",
+			state: func() state.BeaconState {
+				st, err := state_native.InitializeFromProtoDeneb(&ethpb.BeaconStateDeneb{
+					Eth1Data: &ethpb.Eth1Data{
+						BlockHash:    []byte("0x0"),
+						DepositRoot:  make([]byte, 32),
+						DepositCount: 5,
+					},
+					Eth1DepositIndex: 1,
+				})
+				require.NoError(t, err)
+				return st
+			}(),
+			canonicalEth1Data: &ethpb.Eth1Data{
+				BlockHash:    []byte("0x0"),
+				DepositRoot:  make([]byte, 32),
+				DepositCount: 5,
+			},
+			want: true,
+		},
+		{
+			name: "post-electra, pending deposits from pre-electra",
+			state: func() state.BeaconState {
+				st, err := state_native.InitializeFromProtoElectra(&ethpb.BeaconStateElectra{
+					Eth1Data: &ethpb.Eth1Data{
+						BlockHash:    []byte("0x0"),
+						DepositRoot:  make([]byte, 32),
+						DepositCount: 5,
+					},
+					DepositRequestsStartIndex: math.MaxUint64,
+					Eth1DepositIndex:          1,
+				})
+				require.NoError(t, err)
+				return st
+			}(),
+			canonicalEth1Data: &ethpb.Eth1Data{
+				BlockHash:    []byte("0x0"),
+				DepositRoot:  make([]byte, 32),
+				DepositCount: 5,
+			},
+			want: true,
+		},
+		{
+			name: "post-electra, no pending deposits from pre-alpaca",
+			state: func() state.BeaconState {
+				st, err := state_native.InitializeFromProtoElectra(&ethpb.BeaconStateElectra{
+					Eth1Data: &ethpb.Eth1Data{
+						BlockHash:    []byte("0x0"),
+						DepositRoot:  make([]byte, 32),
+						DepositCount: 5,
+					},
+					DepositRequestsStartIndex: 1,
+					Eth1DepositIndex:          5,
+				})
+				require.NoError(t, err)
+				return st
+			}(),
+			canonicalEth1Data: &ethpb.Eth1Data{
+				BlockHash:    []byte("0x0"),
+				DepositRoot:  make([]byte, 32),
+				DepositCount: 5,
+			},
+			want: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := isLegacyDepositProcessPeriod(tt.state, tt.canonicalEth1Data); got != tt.want {
+				t.Errorf("isLegacyDepositProcessPeriod() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}