From 6d7cfe14d89e2e4df86cc18dc90785655f43b8dd Mon Sep 17 00:00:00 2001
From: Tuna <ng.tuna@gmail.com>
Date: Tue, 9 Oct 2018 15:36:41 +0700
Subject: [PATCH] trim m2 set to fit m1 set

---
 contracts/utils.go | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/contracts/utils.go b/contracts/utils.go
index 5f6bc589c5..6046baed85 100644
--- a/contracts/utils.go
+++ b/contracts/utils.go
@@ -579,10 +579,12 @@ func GetM1M2FromCheckpointBlock(checkpointBlock *types.Block) (map[common.Addres
 	validators := ExtractValidatorsFromBytes(checkpointBlock.Header().Validators)
 
 	if len(validators) < len(masternodes) {
-		return nil, errors.New("Len(m2) is less than len(m1)")
+		return nil, errors.New("len(m2) is less than len(m1)")
 	}
-	for i, m1 := range masternodes {
-		m1m2[m1] = masternodes[validators[i]]
+	if len(masternodes) > 0 {
+		for i, m1 := range masternodes {
+			m1m2[m1] = masternodes[validators[i]%int64(len(masternodes))]
+		}
 	}
 	return m1m2, nil
 }