From 03a5dc9c3c522c500c77fdecd52d091db048d1b0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jo=C3=A3o=20Barbosa?= <joao.paulo.barbosa@gmail.com>
Date: Thu, 14 Dec 2017 03:18:29 +0000
Subject: [PATCH] [wallet] Make CWallet::FundTransaction atomic

---
 src/wallet/wallet.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 4777641e72..106c910258 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -2605,6 +2605,10 @@ bool CWallet::FundTransaction(CMutableTransaction& tx, CAmount& nFeeRet, int& nC
         coinControl.Select(txin.prevout);
     }
 
+    // Acquire the locks to prevent races to the new locked unspents between the
+    // CreateTransaction call and LockCoin calls (when lockUnspents is true).
+    LOCK2(cs_main, cs_wallet);
+
     CReserveKey reservekey(this);
     CWalletTx wtx;
     if (!CreateTransaction(vecSend, wtx, reservekey, nFeeRet, nChangePosInOut, strFailReason, coinControl, false)) {
@@ -2630,7 +2634,6 @@ bool CWallet::FundTransaction(CMutableTransaction& tx, CAmount& nFeeRet, int& nC
             tx.vin.push_back(txin);
 
             if (lockUnspents) {
-                LOCK2(cs_main, cs_wallet);
                 LockCoin(txin.prevout);
             }
         }