core: ensure the canonical block is written before the canonical hash is set

1 files changed, 9 insertions, 9 deletions

diff --git a/core/blockchain.go b/core/blockchain.go
index 950804d40..888c98dce 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -778,6 +778,14 @@ func (self *BlockChain) WriteBlock(block *types.Block) (status WriteStatus, err
 	localTd := self.GetTd(self.currentBlock.Hash(), self.currentBlock.NumberU64())
 	externTd := new(big.Int).Add(block.Difficulty(), ptd)
 
+	// Irrelevant of the canonical status, write the block itself to the database
+	if err := self.hc.WriteTd(block.Hash(), block.NumberU64(), externTd); err != nil {
+		glog.Fatalf("failed to write block total difficulty: %v", err)
+	}
+	if err := WriteBlock(self.chainDb, block); err != nil {
+		glog.Fatalf("failed to write block contents: %v", err)
+	}
+
 	// If the total difficulty is higher than our known, add it to the canonical chain
 	// Second clause in the if statement reduces the vulnerability to selfish mining.
 	// Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf
@@ -788,19 +796,11 @@ func (self *BlockChain) WriteBlock(block *types.Block) (status WriteStatus, err
 				return NonStatTy, err
 			}
 		}
-		// Insert the block as the new head of the chain
-		self.insert(block)
+		self.insert(block) // Insert the block as the new head of the chain
 		status = CanonStatTy
 	} else {
 		status = SideStatTy
 	}
-	// Irrelevant of the canonical status, write the block itself to the database
-	if err := self.hc.WriteTd(block.Hash(), block.NumberU64(), externTd); err != nil {
-		glog.Fatalf("failed to write block total difficulty: %v", err)
-	}
-	if err := WriteBlock(self.chainDb, block); err != nil {
-		glog.Fatalf("failed to write block contents: %v", err)
-	}
 
 	self.futureBlocks.Remove(block.Hash())