From 423beddf574383ec58246938f738f08cd50f031a Mon Sep 17 00:00:00 2001
From: obscuren <geffobscura@gmail.com>
Date: Fri, 27 Jun 2014 00:16:49 +0200
Subject: [PATCH] nil check

---
 ethchain/block_chain.go | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/ethchain/block_chain.go b/ethchain/block_chain.go
index d0fea6641..6e4c72b27 100644
--- a/ethchain/block_chain.go
+++ b/ethchain/block_chain.go
@@ -221,9 +221,16 @@ func (bc *BlockChain) GetChainFromHash(hash []byte, max uint64) []interface{} {
 	startNumber := parentNumber + count
 
 	num := lastNumber
-	for ; num > startNumber; currentHash = bc.GetBlock(currentHash).PrevHash {
+	for num > startNumber {
 		num--
+
+		block := bc.GetBlock(currentHash)
+		if block == nil {
+			break
+		}
+		currentHash = block.PrevHash
 	}
+
 	for i := uint64(0); bytes.Compare(currentHash, hash) != 0 && num >= parentNumber && i < count; i++ {
 		// Get the block of the chain
 		block := bc.GetBlock(currentHash)