lock in receive block

beacon-chain/blockchain/block_processing.go

@@ -39,6 +39,8 @@ type BlockProcessor interface {
 // 4. Process and cleanup any block operations, such as attestations and deposits, which would need to be
 //    either included or flushed from the beacon node's runtime.
 func (c *ChainService) ReceiveBlock(ctx context.Context, block *pb.BeaconBlock) (*pb.BeaconState, error) {
+	c.lock.Lock()
+	defer c.lock.Unlock()
 	ctx, span := trace.StartSpan(ctx, "beacon-chain.blockchain.ReceiveBlock")
 	defer span.End()
 	beaconState, err := c.beaconDB.HistoricalStateFromSlot(ctx, block.Slot-1)

beacon-chain/blockchain/fork_choice.go

@@ -122,6 +122,8 @@ func (c *ChainService) ApplyForkChoiceRule(
 	block *pb.BeaconBlock,
 	postState *pb.BeaconState,
 ) error {
+	c.lock.Lock()
+	defer c.lock.Unlock()
 	ctx, span := trace.StartSpan(ctx, "beacon-chain.blockchain.ApplyForkChoiceRule")
 	defer span.End()
 	log.Info("Applying LMD-GHOST Fork Choice Rule")

beacon-chain/blockchain/service.go

@@ -6,6 +6,7 @@ package blockchain
 import (
 	"context"
 	"fmt"
+	"sync"
 	"time"
 
 	"github.com/prysmaticlabs/prysm/beacon-chain/attestation"
@@ -44,6 +45,7 @@ type ChainService struct {
 	finalizedEpoch       uint64
 	stateInitializedFeed *event.Feed
 	p2p                  p2p.Broadcaster
+	lock sync.Mutex
 }
 
 // Config options for the service.