From fa734603b78ba31ebf0da5d2dbe87386eafff01a Mon Sep 17 00:00:00 2001
From: MarcoFalke <falke.marco@gmail.com>
Date: Mon, 19 Aug 2019 17:13:11 -0400
Subject: [PATCH] wallet: Fix segmentation fault in CreateWalletFromFile

---
 src/wallet/wallet.cpp                         |   2 +-
 .../data/wallets/high_minversion/.walletlock  |   0
 .../data/wallets/high_minversion/db.log       |   0
 .../data/wallets/high_minversion/wallet.dat   | Bin 0 -> 16384 bytes
 test/functional/wallet_multiwallet.py         |  25 ++++++++++++++++++
 5 files changed, 26 insertions(+), 1 deletion(-)
 create mode 100644 test/functional/data/wallets/high_minversion/.walletlock
 create mode 100644 test/functional/data/wallets/high_minversion/db.log
 create mode 100644 test/functional/data/wallets/high_minversion/wallet.dat

diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 84fd01730..e5ec8d84b 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -4243,7 +4243,7 @@ bool CWallet::Verify(interfaces::Chain& chain, const WalletLocation& location, b
 
 std::shared_ptr<CWallet> CWallet::CreateWalletFromFile(interfaces::Chain& chain, const WalletLocation& location, uint64_t wallet_creation_flags)
 {
-    const std::string& walletFile = WalletDataFilePath(location.GetPath()).string();
+    const std::string walletFile = WalletDataFilePath(location.GetPath()).string();
 
     // needed to restore wallet transaction meta data after -zapwallettxes
     std::vector<CWalletTx> vWtx;
diff --git a/test/functional/data/wallets/high_minversion/.walletlock b/test/functional/data/wallets/high_minversion/.walletlock
new file mode 100644
index 000000000..e69de29bb
diff --git a/test/functional/data/wallets/high_minversion/db.log b/test/functional/data/wallets/high_minversion/db.log
new file mode 100644
index 000000000..e69de29bb
diff --git a/test/functional/data/wallets/high_minversion/wallet.dat b/test/functional/data/wallets/high_minversion/wallet.dat
new file mode 100644
index 0000000000000000000000000000000000000000..99ab8092631c4a7da2236f46e7250e6c265d3b49
GIT binary patch
literal 16384
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zgMuJV;w&ysI#h6Q^e#1}N(Z+(d=HL$?Ir2;v;BAx5m9E^5lp+1w#AT{aUs%YKX(k@
z)DOp=OquoMDYw#CO0{>L@5(o8^33)o1p){lfB*srAb<b@2q1s}0toa}z-IN%yzWR-
zEB8}3_0R9^A$>E+|5k#500IagfB*srAb<b@2q1vK{}t$ulfENnt>lYQd{CSHZSTHY
z|3B&JC;!Md#b5IO@An3h`&kh{009ILKmY**5I_I{1Q0-=Hv%^Qcjk3Z3a0=6tRMA<
ze$x$os&DkAKGX&CJ^%v&1Q0*~0R#|0009ILKmY**x(kepx_@y*rN*M=;gQVR-C1^P
z@pb)b;(B#<V`g&n_WWY*{oqLFL}i1pz893M+ojE@S_x~Vawy`q?iWu~y1j3H%JlH(
r7fdG4i1I4MXg{pgi&fLoA8ftNA4mF>D0iov->tW<x970?1Ifi-{rf~Z

literal 0
HcmV?d00001

diff --git a/test/functional/wallet_multiwallet.py b/test/functional/wallet_multiwallet.py
index 984ffab5a..2d0a100ac 100755
--- a/test/functional/wallet_multiwallet.py
+++ b/test/functional/wallet_multiwallet.py
@@ -17,6 +17,8 @@ from test_framework.util import (
     assert_raises_rpc_error,
 )
 
+FEATURE_LATEST = 169900
+
 
 class MultiWalletTest(BitcoinTestFramework):
     def set_test_params(self):
@@ -27,6 +29,13 @@ class MultiWalletTest(BitcoinTestFramework):
     def skip_test_if_missing_module(self):
         self.skip_if_no_wallet()
 
+    def add_options(self, parser):
+        parser.add_argument(
+            '--data_wallets_dir',
+            default=os.path.join(os.path.dirname(os.path.realpath(__file__)), 'data/wallets/'),
+            help='Test data with wallet directories (default: %(default)s)',
+        )
+
     def run_test(self):
         node = self.nodes[0]
 
@@ -323,6 +332,22 @@ class MultiWalletTest(BitcoinTestFramework):
         self.nodes[0].unloadwallet(wallet)
         self.nodes[1].loadwallet(wallet)
 
+        # Fail to load if wallet is downgraded
+        shutil.copytree(os.path.join(self.options.data_wallets_dir, 'high_minversion'), wallet_dir('high_minversion'))
+        self.restart_node(0, extra_args=['-upgradewallet={}'.format(FEATURE_LATEST)])
+        assert {'name': 'high_minversion'} in self.nodes[0].listwalletdir()['wallets']
+        self.log.info("Fail -upgradewallet that results in downgrade")
+        assert_raises_rpc_error(
+            -4,
+            "Wallet loading failed.",
+            lambda: self.nodes[0].loadwallet(filename='high_minversion'),
+        )
+        self.stop_node(
+            i=0,
+            expected_stderr='Error: Error loading {}: Wallet requires newer version of Bitcoin Core'.format(
+                wallet_dir('high_minversion', 'wallet.dat')),
+        )
+
 
 if __name__ == '__main__':
     MultiWalletTest().main()