Merge #6441: fix: hold wallet shared pointer in CJ Manager/Sessions t…

…o prevent concurrent unload

2d7c7f8 fix: do not transfer wallet ownership to CTransactionBuilder{Output} (UdjinM6)
0aeeb85 fix: add missing `AddWallet` call in `TestLoadWallet` (UdjinM6)
e800d9d fix: hold wallet shared pointer in CJ Manager/Sessions to prevent concurrent unload (UdjinM6)

Pull request description:

  ## Issue being fixed or feature implemented
  dashpay/dash#6440 (comment)

  ## What was done?

  ## How Has This Been Tested?

  ## Breaking Changes

  ## Checklist:
  - [ ] I have performed a self-review of my own code
  - [ ] I have commented my code, particularly in hard-to-understand areas
  - [ ] I have added or updated relevant unit/integration/functional/e2e tests
  - [ ] I have made corresponding changes to the documentation
  - [ ] I have assigned this pull request to a milestone _(for repository code-owners and collaborators only)_

ACKs for top commit:
  PastaPastaPasta:
    utACK 2d7c7f8

Tree-SHA512: 308e3bed077baa2167b7f9d81b87e5a61a113e4d465706548f303dfc499bc072d4e823e85772e591a879986b0fb0413d5afe0e3995e1f939fa772b29adc0300d

src/coinjoin/client.h

@@ -96,7 +96,7 @@ class CoinJoinWalletManager {
         }
     }
 
-    void Add(CWallet& wallet);
+    void Add(const std::shared_ptr<CWallet>& wallet);
     void DoMaintenance();
 
     void Remove(const std::string& name);
@@ -138,7 +138,7 @@ class CoinJoinWalletManager {
 class CCoinJoinClientSession : public CCoinJoinBaseSession
 {
 private:
-    CWallet& m_wallet;
+    const std::shared_ptr<CWallet> m_wallet;
     CoinJoinWalletManager& m_walletman;
     CCoinJoinClientManager& m_clientman;
     CDeterministicMNManager& m_dmnman;
@@ -163,15 +163,15 @@ class CCoinJoinClientSession : public CCoinJoinBaseSession
     /// Create denominations
     bool CreateDenominated(CAmount nBalanceToDenominate);
     bool CreateDenominated(CAmount nBalanceToDenominate, const CompactTallyItem& tallyItem, bool fCreateMixingCollaterals)
-        EXCLUSIVE_LOCKS_REQUIRED(m_wallet.cs_wallet);
+        EXCLUSIVE_LOCKS_REQUIRED(m_wallet->cs_wallet);
 
     /// Split up large inputs or make fee sized inputs
     bool MakeCollateralAmounts();
     bool MakeCollateralAmounts(const CompactTallyItem& tallyItem, bool fTryDenominated)
-        EXCLUSIVE_LOCKS_REQUIRED(m_wallet.cs_wallet);
+        EXCLUSIVE_LOCKS_REQUIRED(m_wallet->cs_wallet);
 
     bool CreateCollateralTransaction(CMutableTransaction& txCollateral, std::string& strReason)
-        EXCLUSIVE_LOCKS_REQUIRED(m_wallet.cs_wallet);
+        EXCLUSIVE_LOCKS_REQUIRED(m_wallet->cs_wallet);
 
     bool JoinExistingQueue(CAmount nBalanceNeedsAnonymized, CConnman& connman);
     bool StartNewQueue(CAmount nBalanceNeedsAnonymized, CConnman& connman);
@@ -181,7 +181,7 @@ class CCoinJoinClientSession : public CCoinJoinBaseSession
     /// step 1: prepare denominated inputs and outputs
     bool PrepareDenominate(int nMinRounds, int nMaxRounds, std::string& strErrorRet, const std::vector<CTxDSIn>& vecTxDSIn,
                            std::vector<std::pair<CTxDSIn, CTxOut>>& vecPSInOutPairsRet, bool fDryRun = false)
-        EXCLUSIVE_LOCKS_REQUIRED(m_wallet.cs_wallet);
+        EXCLUSIVE_LOCKS_REQUIRED(m_wallet->cs_wallet);
     /// step 2: send denominated inputs and outputs prepared in step 1
     bool SendDenominate(const std::vector<std::pair<CTxDSIn, CTxOut> >& vecPSInOutPairsIn, CConnman& connman) EXCLUSIVE_LOCKS_REQUIRED(!cs_coinjoin);
 
@@ -200,7 +200,7 @@ class CCoinJoinClientSession : public CCoinJoinBaseSession
     void SetNull() override EXCLUSIVE_LOCKS_REQUIRED(cs_coinjoin);
 
 public:
-    explicit CCoinJoinClientSession(CWallet& wallet, CoinJoinWalletManager& walletman,
+    explicit CCoinJoinClientSession(const std::shared_ptr<CWallet>& wallet, CoinJoinWalletManager& walletman,
                                     CCoinJoinClientManager& clientman, CDeterministicMNManager& dmnman,
                                     CMasternodeMetaMan& mn_metaman, const CMasternodeSync& mn_sync,
                                     const std::unique_ptr<CCoinJoinClientQueueManager>& queueman, bool is_masternode);
@@ -267,7 +267,7 @@ class CCoinJoinClientQueueManager : public CCoinJoinBaseManager
 class CCoinJoinClientManager
 {
 private:
-    CWallet& m_wallet;
+    const std::shared_ptr<CWallet> m_wallet;
     CoinJoinWalletManager& m_walletman;
     CDeterministicMNManager& m_dmnman;
     CMasternodeMetaMan& m_mn_metaman;
@@ -306,11 +306,19 @@ class CCoinJoinClientManager
     CCoinJoinClientManager(CCoinJoinClientManager const&) = delete;
     CCoinJoinClientManager& operator=(CCoinJoinClientManager const&) = delete;
 
-    explicit CCoinJoinClientManager(CWallet& wallet, CoinJoinWalletManager& walletman, CDeterministicMNManager& dmnman,
-                                    CMasternodeMetaMan& mn_metaman, const CMasternodeSync& mn_sync,
+    explicit CCoinJoinClientManager(const std::shared_ptr<CWallet>& wallet, CoinJoinWalletManager& walletman,
+                                    CDeterministicMNManager& dmnman, CMasternodeMetaMan& mn_metaman,
+                                    const CMasternodeSync& mn_sync,
                                     const std::unique_ptr<CCoinJoinClientQueueManager>& queueman, bool is_masternode) :
-        m_wallet(wallet), m_walletman(walletman), m_dmnman(dmnman), m_mn_metaman(mn_metaman), m_mn_sync(mn_sync), m_queueman(queueman),
-        m_is_masternode{is_masternode} {}
+        m_wallet(wallet),
+        m_walletman(walletman),
+        m_dmnman(dmnman),
+        m_mn_metaman(mn_metaman),
+        m_mn_sync(mn_sync),
+        m_queueman(queueman),
+        m_is_masternode{is_masternode}
+    {
+    }
 
     void ProcessMessage(CNode& peer, CChainState& active_chainstate, CConnman& connman, const CTxMemPool& mempool, std::string_view msg_type, CDataStream& vRecv) EXCLUSIVE_LOCKS_REQUIRED(!cs_deqsessions);
 

src/coinjoin/interfaces.cpp

@@ -67,10 +67,7 @@ class CoinJoinLoaderImpl : public interfaces::CoinJoin::Loader
     explicit CoinJoinLoaderImpl(CoinJoinWalletManager& walletman)
         : m_walletman(walletman) {}
 
-    void AddWallet(CWallet& wallet) override
-    {
-        m_walletman.Add(wallet);
-    }
+    void AddWallet(const std::shared_ptr<CWallet>& wallet) override { m_walletman.Add(wallet); }
     void RemoveWallet(const std::string& name) override
     {
         m_walletman.Remove(name);

src/coinjoin/util.cpp

@@ -87,14 +87,15 @@ void CKeyHolderStorage::ReturnAll()
     }
 }
 
-CTransactionBuilderOutput::CTransactionBuilderOutput(CTransactionBuilder* pTxBuilderIn, std::shared_ptr<CWallet> pwalletIn, CAmount nAmountIn) :
+CTransactionBuilderOutput::CTransactionBuilderOutput(CTransactionBuilder* pTxBuilderIn,
+                                                     const std::shared_ptr<CWallet>& wallet, CAmount nAmountIn) :
     pTxBuilder(pTxBuilderIn),
-    dest(pwalletIn.get()),
+    dest(wallet.get()),
     nAmount(nAmountIn)
 {
     assert(pTxBuilder);
     CTxDestination txdest;
-    LOCK(pwalletIn->cs_wallet);
+    LOCK(wallet->cs_wallet);
     dest.GetReservedDestination(txdest, false);
     script = ::GetScriptForDestination(txdest);
 }
@@ -108,15 +109,15 @@ bool CTransactionBuilderOutput::UpdateAmount(const CAmount nNewAmount)
     return true;
 }
 
-CTransactionBuilder::CTransactionBuilder(std::shared_ptr<CWallet> pwalletIn, const CompactTallyItem& tallyItemIn) :
-    pwallet(pwalletIn),
-    dummyReserveDestination(pwalletIn.get()),
+CTransactionBuilder::CTransactionBuilder(const std::shared_ptr<CWallet>& wallet, const CompactTallyItem& tallyItemIn) :
+    m_wallet(wallet),
+    dummyReserveDestination(wallet.get()),
     tallyItem(tallyItemIn)
 {
     // Generate a feerate which will be used to consider if the remainder is dust and will go into fees or not
-    coinControl.m_discard_feerate = ::GetDiscardRate(*pwallet);
+    coinControl.m_discard_feerate = ::GetDiscardRate(*m_wallet);
     // Generate a feerate which will be used by calculations of this class and also by CWallet::CreateTransaction
-    coinControl.m_feerate = std::max(GetRequiredFeeRate(*pwallet), pwallet->m_pay_tx_fee);
+    coinControl.m_feerate = std::max(GetRequiredFeeRate(*m_wallet), m_wallet->m_pay_tx_fee);
     // Change always goes back to origin
     coinControl.destChange = tallyItemIn.txdest;
     // Only allow tallyItems inputs for tx creation
@@ -131,16 +132,16 @@ CTransactionBuilder::CTransactionBuilder(std::shared_ptr<CWallet> pwalletIn, con
     // Get a comparable dummy scriptPubKey, avoid writing/flushing to the actual wallet db
     CScript dummyScript;
     {
-        LOCK(pwallet->cs_wallet);
-        WalletBatch dummyBatch(pwallet->GetDatabase(), false);
+        LOCK(m_wallet->cs_wallet);
+        WalletBatch dummyBatch(m_wallet->GetDatabase(), false);
         dummyBatch.TxnBegin();
         CKey secret;
-        secret.MakeNewKey(pwallet->CanSupportFeature(FEATURE_COMPRPUBKEY));
+        secret.MakeNewKey(m_wallet->CanSupportFeature(FEATURE_COMPRPUBKEY));
         CPubKey dummyPubkey = secret.GetPubKey();
         dummyBatch.TxnAbort();
         dummyScript = ::GetScriptForDestination(PKHash(dummyPubkey));
         // Calculate required bytes for the dummy signed tx with tallyItem's inputs only
-        nBytesBase = CalculateMaximumSignedTxSize(CTransaction(dummyTx), pwallet.get(), false);
+        nBytesBase = CalculateMaximumSignedTxSize(CTransaction(dummyTx), m_wallet.get(), false);
     }
     // Calculate the output size
     nBytesOutput = ::GetSerializeSize(CTxOut(0, dummyScript), PROTOCOL_VERSION);
@@ -204,7 +205,7 @@ CTransactionBuilderOutput* CTransactionBuilder::AddOutput(CAmount nAmountOutput)
 {
     if (CouldAddOutput(nAmountOutput)) {
         LOCK(cs_outputs);
-        vecOutputs.push_back(std::make_unique<CTransactionBuilderOutput>(this, pwallet, nAmountOutput));
+        vecOutputs.push_back(std::make_unique<CTransactionBuilderOutput>(this, m_wallet, nAmountOutput));
         return vecOutputs.back().get();
     }
     return nullptr;
@@ -233,12 +234,12 @@ CAmount CTransactionBuilder::GetAmountUsed() const
 CAmount CTransactionBuilder::GetFee(unsigned int nBytes) const
 {
     CAmount nFeeCalc = coinControl.m_feerate->GetFee(nBytes);
-    CAmount nRequiredFee = GetRequiredFee(*pwallet, nBytes);
+    CAmount nRequiredFee = GetRequiredFee(*m_wallet, nBytes);
     if (nRequiredFee > nFeeCalc) {
         nFeeCalc = nRequiredFee;
     }
-    if (nFeeCalc > pwallet->m_default_max_tx_fee) {
-        nFeeCalc = pwallet->m_default_max_tx_fee;
+    if (nFeeCalc > m_wallet->m_default_max_tx_fee) {
+        nFeeCalc = m_wallet->m_default_max_tx_fee;
     }
     return nFeeCalc;
 }
@@ -273,9 +274,9 @@ bool CTransactionBuilder::Commit(bilingual_str& strResult)
 
     CTransactionRef tx;
     {
-        LOCK2(pwallet->cs_wallet, cs_main);
+        LOCK2(m_wallet->cs_wallet, cs_main);
         FeeCalculation fee_calc_out;
-        if (!pwallet->CreateTransaction(vecSend, tx, nFeeRet, nChangePosRet, strResult, coinControl, fee_calc_out)) {
+        if (!m_wallet->CreateTransaction(vecSend, tx, nFeeRet, nChangePosRet, strResult, coinControl, fee_calc_out)) {
             return false;
         }
     }
@@ -312,8 +313,8 @@ bool CTransactionBuilder::Commit(bilingual_str& strResult)
     }
 
     {
-        LOCK2(pwallet->cs_wallet, cs_main);
-        pwallet->CommitTransaction(tx, {}, {});
+        LOCK2(m_wallet->cs_wallet, cs_main);
+        m_wallet->CommitTransaction(tx, {}, {});
     }
 
     fKeepKeys = true;

src/coinjoin/util.h

@@ -54,7 +54,7 @@ class CTransactionBuilderOutput
     CScript script;
 
 public:
-    CTransactionBuilderOutput(CTransactionBuilder* pTxBuilderIn, std::shared_ptr<CWallet> pwalletIn, CAmount nAmountIn);
+    CTransactionBuilderOutput(CTransactionBuilder* pTxBuilderIn, const std::shared_ptr<CWallet>& wallet, CAmount nAmountIn);
     CTransactionBuilderOutput(CTransactionBuilderOutput&&) = delete;
     CTransactionBuilderOutput& operator=(CTransactionBuilderOutput&&) = delete;
     /// Get the scriptPubKey of this output
@@ -77,7 +77,7 @@ class CTransactionBuilderOutput
 class CTransactionBuilder
 {
     /// Wallet the transaction will be build for
-    std::shared_ptr<CWallet> pwallet;
+    const std::shared_ptr<CWallet>& m_wallet;
     /// See CTransactionBuilder() for initialization
     CCoinControl coinControl;
     /// Dummy since we anyway use tallyItem's destination as change destination in coincontrol.
@@ -100,7 +100,7 @@ class CTransactionBuilder
     friend class CTransactionBuilderOutput;
 
 public:
-    CTransactionBuilder(std::shared_ptr<CWallet> pwalletIn, const CompactTallyItem& tallyItemIn);
+    CTransactionBuilder(const std::shared_ptr<CWallet>& wallet, const CompactTallyItem& tallyItemIn);
     ~CTransactionBuilder();
     /// Check it would be possible to add a single output with the amount nAmount. Returns true if its possible and false if not.
     bool CouldAddOutput(CAmount nAmountOutput) const EXCLUSIVE_LOCKS_REQUIRED(!cs_outputs);

src/interfaces/coinjoin.h

@@ -33,7 +33,7 @@ class Loader
 public:
     virtual ~Loader() {}
     //! Add new wallet to CoinJoin client manager
-    virtual void AddWallet(CWallet&) = 0;
+    virtual void AddWallet(const std::shared_ptr<CWallet>&) = 0;
     //! Remove wallet from CoinJoin client manager
     virtual void RemoveWallet(const std::string&) = 0;
     virtual void FlushWallet(const std::string&) = 0;

src/wallet/test/wallet_tests.cpp

@@ -59,6 +59,10 @@ static std::shared_ptr<CWallet> TestLoadWallet(interfaces::Chain* chain, interfa
     std::vector<bilingual_str> warnings;
     auto database = MakeWalletDatabase("", options, status, error);
     auto wallet = CWallet::Create(chain, coinjoin_loader, "", std::move(database), options.create_flags, error, warnings);
+    if (coinjoin_loader) {
+        // TODO: see CreateWalletWithoutChain
+        AddWallet(wallet);
+    }
     if (chain) {
         wallet->postInitProcess();
     }

src/wallet/wallet.cpp

@@ -125,7 +125,7 @@ bool AddWallet(const std::shared_ptr<CWallet>& wallet)
     }
     wallet->ConnectScriptPubKeyManNotifiers();
     wallet->AutoLockMasternodeCollaterals();
-    wallet->coinjoin_loader().AddWallet(*wallet);
+    wallet->coinjoin_loader().AddWallet(wallet);
     wallet->NotifyCanGetAddressesChanged();
     return true;
 }
@@ -1432,46 +1432,46 @@ int CWallet::GetRealOutpointCoinJoinRounds(const COutPoint& outpoint, int nRound
     if (wtx == nullptr || wtx->tx == nullptr) {
         // no such tx in this wallet
         *nRoundsRef = -1;
-        WalletCJLogPrint((*this), "%s FAILED    %-70s %3d\n", __func__, outpoint.ToStringShort(), -1);
+        WalletCJLogPrint(this, "%s FAILED    %-70s %3d\n", __func__, outpoint.ToStringShort(), -1);
         return *nRoundsRef;
     }
 
     // bounds check
     if (outpoint.n >= wtx->tx->vout.size()) {
         // should never actually hit this
         *nRoundsRef = -4;
-        WalletCJLogPrint((*this), "%s FAILED    %-70s %3d\n", __func__, outpoint.ToStringShort(), -4);
+        WalletCJLogPrint(this, "%s FAILED    %-70s %3d\n", __func__, outpoint.ToStringShort(), -4);
         return *nRoundsRef;
     }
 
     auto txOutRef = &wtx->tx->vout[outpoint.n];
 
     if (CoinJoin::IsCollateralAmount(txOutRef->nValue)) {
         *nRoundsRef = -3;
-        WalletCJLogPrint((*this), "%s UPDATED   %-70s %3d\n", __func__, outpoint.ToStringShort(), *nRoundsRef);
+        WalletCJLogPrint(this, "%s UPDATED   %-70s %3d\n", __func__, outpoint.ToStringShort(), *nRoundsRef);
         return *nRoundsRef;
     }
 
     // make sure the final output is non-denominate
     if (!CoinJoin::IsDenominatedAmount(txOutRef->nValue)) { //NOT DENOM
         *nRoundsRef = -2;
-        WalletCJLogPrint((*this), "%s UPDATED   %-70s %3d\n", __func__, outpoint.ToStringShort(), *nRoundsRef);
+        WalletCJLogPrint(this, "%s UPDATED   %-70s %3d\n", __func__, outpoint.ToStringShort(), *nRoundsRef);
         return *nRoundsRef;
     }
 
     for (const auto& out : wtx->tx->vout) {
         if (!CoinJoin::IsDenominatedAmount(out.nValue)) {
             // this one is denominated but there is another non-denominated output found in the same tx
             *nRoundsRef = 0;
-            WalletCJLogPrint((*this), "%s UPDATED   %-70s %3d\n", __func__, outpoint.ToStringShort(), *nRoundsRef);
+            WalletCJLogPrint(this, "%s UPDATED   %-70s %3d\n", __func__, outpoint.ToStringShort(), *nRoundsRef);
             return *nRoundsRef;
         }
     }
 
     // make sure we spent all of it with 0 fee, reset to 0 rounds otherwise
     if (wtx->GetDebit(ISMINE_SPENDABLE) != wtx->GetCredit(ISMINE_SPENDABLE)) {
         *nRoundsRef = 0;
-        WalletCJLogPrint((*this), "%s UPDATED   %-70s %3d\n", __func__, outpoint.ToStringShort(), *nRoundsRef);
+        WalletCJLogPrint(this, "%s UPDATED   %-70s %3d\n", __func__, outpoint.ToStringShort(), *nRoundsRef);
         return *nRoundsRef;
     }
 
@@ -1491,7 +1491,7 @@ int CWallet::GetRealOutpointCoinJoinRounds(const COutPoint& outpoint, int nRound
     *nRoundsRef = fDenomFound
             ? (nShortest >= nRoundsMax - 1 ? nRoundsMax : nShortest + 1) // good, we a +1 to the shortest one but only nRoundsMax rounds max allowed
             : 0;            // too bad, we are the fist one in that chain
-    WalletCJLogPrint((*this), "%s UPDATED   %-70s %3d\n", __func__, outpoint.ToStringShort(), *nRoundsRef);
+    WalletCJLogPrint(this, "%s UPDATED   %-70s %3d\n", __func__, outpoint.ToStringShort(), *nRoundsRef);
     return *nRoundsRef;
 }
 
@@ -3253,7 +3253,7 @@ bool CWallet::SelectTxDSInsByDenomination(int nDenom, CAmount nValueMax, std::ve
     CCoinControl coin_control;
     coin_control.nCoinType = CoinType::ONLY_READY_TO_MIX;
     AvailableCoins(vCoins, &coin_control);
-    WalletCJLogPrint((*this), "CWallet::%s -- vCoins.size(): %d\n", __func__, vCoins.size());
+    WalletCJLogPrint(this, "CWallet::%s -- vCoins.size(): %d\n", __func__, vCoins.size());
 
     Shuffle(vCoins.rbegin(), vCoins.rend(), FastRandomContext());
 
@@ -3271,11 +3271,11 @@ bool CWallet::SelectTxDSInsByDenomination(int nDenom, CAmount nValueMax, std::ve
         nValueTotal += nValue;
         vecTxDSInRet.emplace_back(CTxDSIn(txin, scriptPubKey, nRounds));
         setRecentTxIds.emplace(txHash);
-        WalletCJLogPrint((*this), "CWallet::%s -- hash: %s, nValue: %d.%08d\n",
+        WalletCJLogPrint(this, "CWallet::%s -- hash: %s, nValue: %d.%08d\n",
                         __func__, txHash.ToString(), nValue / COIN, nValue % COIN);
     }
 
-    WalletCJLogPrint((*this), "CWallet::%s -- setRecentTxIds.size(): %d\n", __func__, setRecentTxIds.size());
+    WalletCJLogPrint(this, "CWallet::%s -- setRecentTxIds.size(): %d\n", __func__, setRecentTxIds.size());
 
     return nValueTotal > 0;
 }
@@ -4980,7 +4980,7 @@ std::shared_ptr<CWallet> CWallet::Create(interfaces::Chain* chain, interfaces::C
     }
 
     if (coinjoin_loader) {
-        coinjoin_loader->AddWallet(*walletInstance);
+        coinjoin_loader->AddWallet(walletInstance);
     }
 
     {

src/wallet/wallet.h

@@ -153,7 +153,7 @@ extern const std::map<uint64_t,std::string> WALLET_FLAG_CAVEATS;
 #define WalletCJLogPrint(wallet, ...)                                  \
     do {                                                               \
         if (LogAcceptCategory(BCLog::COINJOIN, BCLog::Level::Debug)) { \
-            wallet.WalletLogPrintf(__VA_ARGS__);                       \
+            wallet->WalletLogPrintf(__VA_ARGS__);                      \
         }                                                              \
     } while (0)