wallet: Reload watchonly and solvables wallets after migration

src/wallet/transaction.cpp

@@ -24,4 +24,9 @@ int64_t CWalletTx::GetTxTime() const
     int64_t n = nTimeSmart;
     return n ? n : nTimeReceived;
 }
+
+void CWalletTx::CopyFrom(const CWalletTx& _tx)
+{
+    *this = _tx;
+}
 } // namespace wallet

src/wallet/transaction.h

@@ -323,11 +323,15 @@ class CWalletTx
     const uint256& GetWitnessHash() const { return tx->GetWitnessHash(); }
     bool IsCoinBase() const { return tx->IsCoinBase(); }
 
+private:
     // Disable copying of CWalletTx objects to prevent bugs where instances get
     // copied in and out of the mapWallet map, and fields are updated in the
     // wrong copy.
-    CWalletTx(CWalletTx const &) = delete;
-    void operator=(CWalletTx const &x) = delete;
+    CWalletTx(const CWalletTx&) = default;
+    CWalletTx& operator=(const CWalletTx&) = default;
+public:
+    // Instead have an explicit copy function
+    void CopyFrom(const CWalletTx&);
 };
 
 struct WalletTxOrderComparator {

src/wallet/wallet.cpp

@@ -3908,6 +3908,14 @@ bool CWallet::ApplyMigrationData(MigrationData& data, bilingual_str& error)
     // Check if the transactions in the wallet are still ours. Either they belong here, or they belong in the watchonly wallet.
     // We need to go through these in the tx insertion order so that lookups to spends works.
     std::vector<uint256> txids_to_delete;
+    std::unique_ptr<WalletBatch> watchonly_batch;
+    if (data.watchonly_wallet) {
+        watchonly_batch = std::make_unique<WalletBatch>(data.watchonly_wallet->GetDatabase());
+        // Copy the next tx order pos to the watchonly wallet
+        LOCK(data.watchonly_wallet->cs_wallet);
+        data.watchonly_wallet->nOrderPosNext = nOrderPosNext;
+        watchonly_batch->WriteOrderPosNext(data.watchonly_wallet->nOrderPosNext);
+    }
     for (const auto& [_pos, wtx] : wtxOrdered) {
         if (!IsMine(*wtx->tx) && !IsFromMe(*wtx->tx)) {
             // Check it is the watchonly wallet's
@@ -3916,12 +3924,20 @@ bool CWallet::ApplyMigrationData(MigrationData& data, bilingual_str& error)
                 LOCK(data.watchonly_wallet->cs_wallet);
                 if (data.watchonly_wallet->IsMine(*wtx->tx) || data.watchonly_wallet->IsFromMe(*wtx->tx)) {
                     // Add to watchonly wallet
-                    if (!data.watchonly_wallet->AddToWallet(wtx->tx, wtx->m_state)) {
-                        error = _("Error: Could not add watchonly tx to watchonly wallet");
+                    const uint256& hash = wtx->GetHash();
+                    const CWalletTx& to_copy_wtx = *wtx;
+                    if (!data.watchonly_wallet->LoadToWallet(hash, [&](CWalletTx& ins_wtx, bool new_tx) EXCLUSIVE_LOCKS_REQUIRED(data.watchonly_wallet->cs_wallet) {
+                        if (!new_tx) return false;
+                        ins_wtx.SetTx(to_copy_wtx.tx);
+                        ins_wtx.CopyFrom(to_copy_wtx);
+                        return true;
+                    })) {
+                        error = strprintf(_("Error: Could not add watchonly tx %s to watchonly wallet"), wtx->GetHash().GetHex());
                         return false;
                     }
+                    watchonly_batch->WriteTx(data.watchonly_wallet->mapWallet.at(hash));
                     // Mark as to remove from this wallet
-                    txids_to_delete.push_back(wtx->GetHash());
+                    txids_to_delete.push_back(hash);
                     continue;
                 }
             }
@@ -3930,6 +3946,7 @@ bool CWallet::ApplyMigrationData(MigrationData& data, bilingual_str& error)
             return false;
         }
     }
+    watchonly_batch.reset(); // Flush
     // Do the removes
     if (txids_to_delete.size() > 0) {
         std::vector<uint256> deleted_txids;

test/functional/wallet_migration.py

@@ -6,11 +6,14 @@
 
 import random
 import shutil
+import struct
+
 from test_framework.address import (
     script_to_p2sh,
     key_to_p2pkh,
     key_to_p2wpkh,
 )
+from test_framework.bdb import BTREE_MAGIC
 from test_framework.descriptors import descsum_create
 from test_framework.key import ECPubKey
 from test_framework.test_framework import BitcoinTestFramework
@@ -20,6 +23,7 @@
     assert_equal,
     assert_raises_rpc_error,
     find_vout_for_address,
+    sha256sum_file,
 )
 from test_framework.wallet_util import (
     get_generate_key,
@@ -827,6 +831,43 @@ def test_hybrid_pubkey(self):
 
         wallet.unloadwallet()
 
+    def test_failed_migration_cleanup(self):
+        self.log.info("Test that a failed migration is cleaned up")
+        wallet = self.create_legacy_wallet("failed")
+
+        # Make a copy of the wallet with the solvables wallet name so that we are unable
+        # to create the solvables wallet when migrating, thus failing to migrate
+        wallet.unloadwallet()
+        solvables_path = self.nodes[0].wallets_path / "failed_solvables"
+        shutil.copytree(self.nodes[0].wallets_path / "failed", solvables_path)
+        original_shasum = sha256sum_file(solvables_path / "wallet.dat")
+
+        self.nodes[0].loadwallet("failed")
+
+        # Add a multisig so that a solvables wallet is created
+        wallet.addmultisigaddress(2, [wallet.getnewaddress(), get_generate_key().pubkey])
+        wallet.importaddress(get_generate_key().p2pkh_addr)
+
+        assert_raises_rpc_error(-4, "Failed to create new watchonly wallet", wallet.migratewallet)
+
+        assert "failed" in self.nodes[0].listwallets()
+        assert "failed_watchonly" not in self.nodes[0].listwallets()
+        assert "failed_solvables" not in self.nodes[0].listwallets()
+
+        assert not (self.nodes[0].wallets_path / "failed_watchonly").exists()
+        # Since the file in failed_solvables is one that we put there, migration shouldn't touch it
+        assert solvables_path.exists()
+        new_shasum = sha256sum_file(solvables_path / "wallet.dat")
+        assert_equal(original_shasum, new_shasum)
+
+        wallet.unloadwallet()
+        # Check the wallet we tried to migrate is still BDB
+        with open(self.nodes[0].wallets_path / "failed" / "wallet.dat", "rb") as f:
+            data = f.read(16)
+            _, _, magic = struct.unpack("QII", data)
+            assert_equal(magic, BTREE_MAGIC)
+
+
     def run_test(self):
         self.generate(self.nodes[0], 101)
 
@@ -845,6 +886,7 @@ def run_test(self):
         self.test_migrate_raw_p2sh()
         self.test_conflict_txs()
         self.test_hybrid_pubkey()
+        self.test_failed_migration_cleanup()
 
 if __name__ == '__main__':
     WalletMigrationTest().main()