From fd44d48b24b9153e76ffd9a023aafe522e815c7b Mon Sep 17 00:00:00 2001 From: furszy Date: Fri, 2 Jan 2026 14:02:21 -0500 Subject: [PATCH 1/2] wallet: fix ancient wallets migration The best block locator was introduced in #152, previously created wallets do not have these record. --- src/wallet/wallet.cpp | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp index bc27018cd2f..0b20b37eec0 100644 --- a/src/wallet/wallet.cpp +++ b/src/wallet/wallet.cpp @@ -3950,10 +3950,9 @@ util::Result CWallet::ApplyMigrationData(WalletBatch& local_wallet_batch, } // Get best block locator so that we can copy it to the watchonly and solvables + // Note: The best block locator was introduced in #152 so ancient wallets do not have it CBlockLocator best_block_locator; - if (!local_wallet_batch.ReadBestBlock(best_block_locator)) { - return util::Error{_("Error: Unable to read wallet's best block locator record")}; - } + (void)local_wallet_batch.ReadBestBlock(best_block_locator); // Update m_txos to match the descriptors remaining in this wallet m_txos.clear(); @@ -3970,7 +3969,7 @@ util::Result CWallet::ApplyMigrationData(WalletBatch& local_wallet_batch, LOCK(data.watchonly_wallet->cs_wallet); data.watchonly_wallet->nOrderPosNext = nOrderPosNext; watchonly_batch->WriteOrderPosNext(data.watchonly_wallet->nOrderPosNext); - // Write the best block locator to avoid rescanning on reload + // Write the locator record. An empty locator is valid and triggers rescan on load. if (!watchonly_batch->WriteBestBlock(best_block_locator)) { return util::Error{_("Error: Unable to write watchonly wallet best block locator record")}; } @@ -3979,7 +3978,7 @@ util::Result CWallet::ApplyMigrationData(WalletBatch& local_wallet_batch, if (data.solvable_wallet) { solvables_batch = std::make_unique(data.solvable_wallet->GetDatabase()); if (!solvables_batch->TxnBegin()) return util::Error{strprintf(_("Error: database transaction cannot be executed for wallet %s"), data.solvable_wallet->GetName())}; - // Write the best block locator to avoid rescanning on reload + // Write the locator record. An empty locator is valid and triggers rescan on load. if (!solvables_batch->WriteBestBlock(best_block_locator)) { return util::Error{_("Error: Unable to write solvable wallet best block locator record")}; } From b86c1c443d89a50547efd422635e378b5e8f5e87 Mon Sep 17 00:00:00 2001 From: furszy Date: Sat, 3 Jan 2026 11:41:40 -0500 Subject: [PATCH 2/2] test: add coverage for migrating ancient wallets Pre-#152 wallets have no best block stored. Test we can migrate them. --- test/functional/wallet_migration.py | 31 +++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/test/functional/wallet_migration.py b/test/functional/wallet_migration.py index 45ebd435cde..d3d776d1b7f 100755 --- a/test/functional/wallet_migration.py +++ b/test/functional/wallet_migration.py @@ -1659,6 +1659,36 @@ class WalletMigrationTest(BitcoinTestFramework): self.clear_default_wallet(backup_path) + @staticmethod + def erase_bdb_record(wallet_dat_path, key): + data = bytearray(wallet_dat_path.read_bytes()) + idx = data.find(key) + assert idx != -1, f"{key!r} not found in wallet.dat" + + for i in range(idx, idx + len(key)): + data[i] = 0 + + wallet_dat_path.write_bytes(data) + + def test_missing_bestblock(self): + self.log.info("Test migrating legacy BDB wallet without bestblock record") + wallet_name = "nobestblock" + wallet = self.create_legacy_wallet(wallet_name) + wallet.unloadwallet() + + # Erase block locator records like if this would be a pre-#152 wallet + self.erase_bdb_record(self.old_node.wallets_path / wallet_name / "wallet.dat", b"bestblock_nomerkle") + self.erase_bdb_record(self.old_node.wallets_path / wallet_name / "wallet.dat", b"bestblock") + + shutil.copytree(self.old_node.wallets_path / wallet_name, self.master_node.wallets_path / wallet_name, dirs_exist_ok=True) + # Migrate, checking that rescan occurs + with self.master_node.assert_debug_log(expected_msgs=["Rescanning"], unexpected_msgs=[]): + self.master_node.migratewallet(wallet_name) + + wallet = self.master_node.get_wallet_rpc(wallet_name) + info = wallet.getwalletinfo() + assert_equal(info["descriptors"], True) + assert_equal(info["format"], "sqlite") def run_test(self): self.master_node = self.nodes[0] @@ -1708,6 +1738,7 @@ class WalletMigrationTest(BitcoinTestFramework): self.test_taproot() self.test_solvable_no_privs() self.test_loading_failure_after_migration() + self.test_missing_bestblock() # Note: After this test the first 250 blocks of 'master_node' are pruned self.unsynced_wallet_on_pruned_node_fails()