add log deepcopy to ensure complete replica of state

implement "deep copy" as go-ethereum

core/state/statedb.go

@@ -489,8 +489,8 @@ func (self *StateDB) createObject(addr common.Address) (newobj, prev *stateObjec
 // CreateAccount is called during the EVM CREATE operation. The situation might arise that
 // a contract does the following:
 //
-//   1. sends funds to sha(account ++ (nonce + 1))
-//   2. tx_create(sha(account ++ nonce)) (note that this gets the address of 1)
+//  1. sends funds to sha(account ++ (nonce + 1))
+//  2. tx_create(sha(account ++ nonce)) (note that this gets the address of 1)
 //
 // Carrying over the balance ensures that Ether doesn't disappear.
 func (self *StateDB) CreateAccount(addr common.Address) {
@@ -544,10 +544,17 @@ func (self *StateDB) Copy() *StateDB {
 		state.stateObjects[addr] = self.stateObjects[addr].deepCopy(state, state.MarkStateObjectDirty)
 		state.stateObjectsDirty[addr] = struct{}{}
 	}
+
+	// Deep copy the logs occurred in the scope of block
 	for hash, logs := range self.logs {
-		state.logs[hash] = make([]*types.Log, len(logs))
-		copy(state.logs[hash], logs)
+		cpy := make([]*types.Log, len(logs))
+		for i, l := range logs {
+			cpy[i] = new(types.Log)
+			*cpy[i] = *l
+		}
+		state.logs[hash] = cpy
 	}
+
 	for hash, preimage := range self.preimages {
 		state.preimages[hash] = preimage
 	}