From 9c8006dc332139069d798f39406ec67186ecb311 Mon Sep 17 00:00:00 2001 From: Russell Yanofsky Date: Tue, 10 Oct 2017 15:27:26 -0400 Subject: [PATCH] Avoid opening copied wallet databases simultaneously Make sure wallet databases have unique fileids. If they don't, throw an error. BDB caches do not work properly when more than one open database has the same fileid, because values written to one database may show up in reads to other databases. Bitcoin will never create different databases with the same fileid, but users can create them by manually copying database files. BDB caching bug was reported by Chris Moore https://github.com/bitcoin/bitcoin/issues/11429 Fixes #11429 Github-Pull: #11476 Rebased-From: 478a89c1ef79a75275d1b508122c06eee9386b2d --- src/wallet/db.cpp | 35 ++++++++++++++++++++++++++++++++++ test/functional/multiwallet.py | 6 ++++++ 2 files changed, 41 insertions(+) diff --git a/src/wallet/db.cpp b/src/wallet/db.cpp index f5f96768b..fb6e57607 100644 --- a/src/wallet/db.cpp +++ b/src/wallet/db.cpp @@ -20,6 +20,40 @@ #include +namespace { +//! Make sure database has a unique fileid within the environment. If it +//! doesn't, throw an error. BDB caches do not work properly when more than one +//! open database has the same fileid (values written to one database may show +//! up in reads to other databases). +//! +//! BerkeleyDB generates unique fileids by default +//! (https://docs.oracle.com/cd/E17275_01/html/programmer_reference/program_copy.html), +//! so bitcoin should never create different databases with the same fileid, but +//! this error can be triggered if users manually copy database files. +void CheckUniqueFileid(const CDBEnv& env, const std::string& filename, Db& db) +{ + if (env.IsMock()) return; + + u_int8_t fileid[DB_FILE_ID_LEN]; + int ret = db.get_mpf()->get_fileid(fileid); + if (ret != 0) { + throw std::runtime_error(strprintf("CDB: Can't open database %s (get_fileid failed with %d)", filename, ret)); + } + + for (const auto& item : env.mapDb) { + u_int8_t item_fileid[DB_FILE_ID_LEN]; + if (item.second && item.second->get_mpf()->get_fileid(item_fileid) == 0 && + memcmp(fileid, item_fileid, sizeof(fileid)) == 0) { + const char* item_filename = nullptr; + item.second->get_dbname(&item_filename, nullptr); + throw std::runtime_error(strprintf("CDB: Can't open database %s (duplicates fileid %s from %s)", filename, + HexStr(std::begin(item_fileid), std::end(item_fileid)), + item_filename ? item_filename : "(unknown database)")); + } + } +} +} // namespace + // // CDB // @@ -403,6 +437,7 @@ CDB::CDB(CWalletDBWrapper& dbw, const char* pszMode, bool fFlushOnCloseIn) : pdb if (ret != 0) { throw std::runtime_error(strprintf("CDB: Error %d, can't open database %s", ret, strFilename)); } + CheckUniqueFileid(*env, strFilename, *pdb_temp); pdb = pdb_temp.release(); env->mapDb[strFilename] = pdb; diff --git a/test/functional/multiwallet.py b/test/functional/multiwallet.py index 6adcc1fd8..ba6b659dd 100755 --- a/test/functional/multiwallet.py +++ b/test/functional/multiwallet.py @@ -7,6 +7,7 @@ Verify that a bitcoind node can load multiple wallet files """ import os +import shutil from test_framework.test_framework import BitcoinTestFramework from test_framework.util import assert_equal, assert_raises_rpc_error @@ -29,6 +30,11 @@ class MultiWalletTest(BitcoinTestFramework): os.mkdir(os.path.join(self.options.tmpdir, 'node0', 'regtest', 'w11')) self.assert_start_raises_init_error(0, ['-wallet=w11'], 'Error loading wallet w11. -wallet filename must be a regular file.') + # should not initialize if one wallet is a copy of another + shutil.copyfile(os.path.join(self.options.tmpdir, 'node0', 'regtest', 'w2'), + os.path.join(self.options.tmpdir, 'node0', 'regtest', 'w22')) + self.assert_start_raises_init_error(0, ['-wallet=w2', '-wallet=w22'], 'duplicates fileid') + # should not initialize if wallet file is a symlink os.symlink(os.path.join(self.options.tmpdir, 'node0', 'regtest', 'w1'), os.path.join(self.options.tmpdir, 'node0', 'regtest', 'w12')) self.assert_start_raises_init_error(0, ['-wallet=w12'], 'Error loading wallet w12. -wallet filename must be a regular file.')