Merge pull request #7384 from ClickHouse/fix_ub_in_system_parts

alexey-milovidov · web-flow · commit 52bfa9927c79 · 2019-10-19T09:59:39.000+03:00
Fix UB in StoragesInfoStream
diff --git a/dbms/src/Storages/System/StorageSystemPartsBase.cpp b/dbms/src/Storages/System/StorageSystemPartsBase.cpp
@@ -77,7 +77,9 @@ StoragesInfoStream::StoragesInfoStream(const SelectQueryInfo & query_info, const
         MutableColumnPtr database_column_mut = ColumnString::create();
         for (const auto & database : databases)
         {
-            if (context.hasDatabaseAccessRights(database.first))
+            /// Lazy database can not contain MergeTree tables
+            /// and it's unnecessary to load all tables of Lazy database just to filter all of them.
+            if (context.hasDatabaseAccessRights(database.first) && database.second->getEngineName() != "Lazy")
                 database_column_mut->insert(database.first);
         }
         block_to_filter.insert(ColumnWithTypeAndName(
@@ -101,10 +103,6 @@ StoragesInfoStream::StoragesInfoStream(const SelectQueryInfo & query_info, const
                 String database_name = (*database_column_)[i].get<String>();
                 const DatabasePtr database = databases.at(database_name);
 
-                /// Lazy database can not contain MergeTree tables
-                if (database->getEngineName() == "Lazy")
-                    continue;
-
                 offsets[i] = i ? offsets[i - 1] : 0;
                 for (auto iterator = database->getIterator(context); iterator->isValid(); iterator->next())
                 {
diff --git a/dbms/tests/queries/0_stateless/00961_checksums_in_system_parts_columns_table.sql b/dbms/tests/queries/0_stateless/00961_checksums_in_system_parts_columns_table.sql
@@ -11,7 +11,7 @@ SELECT
     hash_of_uncompressed_files, 
     uncompressed_hash_of_compressed_files
 FROM system.parts
-WHERE table = 'test_00961';
+WHERE table = 'test_00961' and database = currentDatabase();
 
 DROP TABLE test_00961;
 
diff --git a/dbms/tests/queries/0_stateless/01014_lazy_database_basic.sh b/dbms/tests/queries/0_stateless/01014_lazy_database_basic.sh
@@ -3,6 +3,7 @@
 CURDIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
 . $CURDIR/../shell_config.sh
 
+${CLICKHOUSE_CLIENT} -n -q "DROP DATABASE IF EXISTS testlazy"
 
 ${CLICKHOUSE_CLIENT} -n -q "
     CREATE DATABASE testlazy ENGINE = Lazy(1);
@@ -11,6 +12,8 @@ ${CLICKHOUSE_CLIENT} -n -q "
     CREATE TABLE testlazy.tlog (a UInt64, b UInt64) ENGINE = TinyLog;
 "
 
+${CLICKHOUSE_CLIENT} -q "SELECT * FROM system.parts WHERE database = 'testlazy'";
+
 sleep 1.5
 
 ${CLICKHOUSE_CLIENT} -q "
