eth/downloader: fix snap sync of the db on the path scheme

Author: qianhh

eth/downloader/downloader.go

@@ -468,6 +468,23 @@ func (d *Downloader) syncWithPeer(p *peerConnection, hash common.Hash, td, ttd *
 		if err != nil {
 			return err
 		}
+		if d.blockchain.TrieDB().Scheme() == rawdb.PathScheme && mode == SnapSync {
+			// Ensure the pivot is above the minimum full block threshold
+			pivotNumber := uint64(0)
+			if pivot != nil {
+				pivotNumber = pivot.Number.Uint64()
+			}
+			if pivotNumber < uint64(fsMinFullBlocks) {
+				block := d.blockchain.CurrentBlock()
+				if err = d.blockchain.TrieDB().Enable(block.Root); err != nil {
+					return fmt.Errorf("failed to enable trie db: %v", err)
+				}
+				log.Info("Disabling snap sync of the db on the path scheme due to the pivot header being positioned too low",
+					"pivot", pivotNumber)
+				<-time.After(3 * time.Second)
+				return errCanceled
+			}
+		}
 	} else {
 		// In beacon mode, use the skeleton chain to retrieve the headers from
 		latest, _, final, err = d.skeleton.Bounds()

eth/handler_eth.go

@@ -65,7 +65,7 @@ func (h *ethHandler) Handle(peer *eth.Peer, packet eth.Packet) error {
 		return h.handleBlockAnnounces(peer, hashes, numbers)
 
 	case *eth.NewBlockPacket:
-		return h.handleBlockBroadcast(peer, packet.Block, packet.TD)
+		return h.handleBlockBroadcast(peer, packet)
 
 	case *eth.NewPooledTransactionHashesPacket:
 		return h.txFetcher.Notify(peer.ID(), packet.Types, packet.Sizes, packet.Hashes)
@@ -121,7 +121,10 @@ func (h *ethHandler) handleBlockAnnounces(peer *eth.Peer, hashes []common.Hash,
 
 // handleBlockBroadcast is invoked from a peer's message handler when it transmits a
 // block broadcast for the local node to process.
-func (h *ethHandler) handleBlockBroadcast(peer *eth.Peer, block *types.Block, td *big.Int) error {
+func (h *ethHandler) handleBlockBroadcast(peer *eth.Peer, packet *eth.NewBlockPacket) error {
+	block := packet.Block
+	td := packet.TD
+
 	// Schedule the block for import
 	h.blockFetcher.Enqueue(peer.ID(), block)