From 269a7ee8d4c470a429f84965d796d14151b8b807 Mon Sep 17 00:00:00 2001
From: Bas van Kervel <basvankervel@gmail.com>
Date: Mon, 21 Nov 2016 12:31:24 +0100
Subject: [PATCH] core/quorum: check if transaction was already applied

Due to the asynchronous eventing system its possible that transactions
are applied on the pending state multiple times. Once with the TxPreEvent
event and once as a result of the ChainHeadEvent that will fetch all
processable transaction from the transaction pool. This leads to an
invalid nonce message.

This PR will keep track of transactions applied to the pending state
and will verify that an transaction was not applied before.
---
 core/quorum/block_maker.go  | 7 +++++++
 core/quorum/block_voting.go | 3 +++
 2 files changed, 10 insertions(+)

diff --git a/core/quorum/block_maker.go b/core/quorum/block_maker.go
index a5e6b0aaf..233621023 100755
--- a/core/quorum/block_maker.go
+++ b/core/quorum/block_maker.go
@@ -26,6 +26,7 @@ type pendingState struct {
 	gp                        *core.GasPool
 	ownedAccounts             *set.Set
 	txs                       types.Transactions // set of transactions
+	txsHashes                 *set.Set
 	lowGasTxs                 types.Transactions
 	failedTxs                 types.Transactions
 	parent                    *types.Block
@@ -55,6 +56,7 @@ func (ps *pendingState) applyTransaction(tx *types.Transaction, bc *core.BlockCh
 		return err, nil
 	}
 	ps.txs = append(ps.txs, tx)
+	ps.txsHashes.Add(tx.Hash())
 	ps.receipts = append(ps.receipts, receipt)
 
 	return nil, logs
@@ -73,6 +75,11 @@ func (ps *pendingState) applyTransactions(txs *types.TransactionsByPriorityAndNo
 		if tx == nil {
 			break
 		}
+
+		if ps.txsHashes.Has(tx.Hash()) {
+			continue
+		}
+
 		// Error may be ignored here. The error has already been checked
 		// during transaction acceptance is the transaction pool.
 		from, _ := tx.From()
diff --git a/core/quorum/block_voting.go b/core/quorum/block_voting.go
index ea30c467b..8271cb7df 100755
--- a/core/quorum/block_voting.go
+++ b/core/quorum/block_voting.go
@@ -110,6 +110,7 @@ func (bv *BlockVoting) resetPendingState(parent *types.Block) {
 		header:        bv.makeHeader(parent),
 		gp:            new(core.GasPool),
 		ownedAccounts: accountAddressesSet(bv.am.Accounts()),
+		txsHashes:     set.New(),
 	}
 
 	ps.gp.AddGas(ps.header.GasLimit)
@@ -310,9 +311,11 @@ func (bv *BlockVoting) createBlock() (*types.Block, error) {
 
 	ch, err := bv.canonHash(bv.pState.header.Number.Uint64())
 	if err != nil {
+		bv.resetPendingState(bv.bc.CurrentFastBlock())
 		return nil, err
 	}
 	if ch != bv.pState.parent.Hash() {
+		bv.resetPendingState(bv.bc.CurrentFastBlock())
 		return nil, fmt.Errorf("invalid canonical hash, expected %s got %s", ch.Hex(), bv.pState.header.Hash().Hex())
 	}