MDEV-25899 intermediate files operations are not protected by backup10.6-MDEV-25899

locks

Test case.

5 files changed, 63 insertions, 5 deletions

diff --git a/extra/mariabackup/backup_copy.cc b/extra/mariabackup/backup_copy.cc
index 7735796e8a4..dbf916d947b 100644
--- a/extra/mariabackup/backup_copy.cc
+++ b/extra/mariabackup/backup_copy.cc
@@ -1421,6 +1421,21 @@ bool backup_start(CorruptedPages &corrupted_pages)
 		}
 
 		history_lock_time = time(NULL);
+		DBUG_EXECUTE_IF("emulate_ddl_on_intermediate_table",
+			dbug_emulate_ddl_on_intermediate_table_thread =
+			dbug_start_query_thread(
+				"SET debug_sync='copy_data_between_tables_after_set_backup_lock "
+				"SIGNAL copy_started';"
+				"SET debug_sync='copy_data_between_tables_before_reset_backup_lock "
+				"SIGNAL before_backup_lock_reset WAIT_FOR backup_lock_reset';"
+				"SET debug_sync='alter_table_after_temp_table_drop "
+				"SIGNAL temp_table_dropped';"
+				"SET SESSION lock_wait_timeout = 1;"
+				"ALTER TABLE test.t1 ADD COLUMN col1_copy INT, ALGORITHM = COPY;",
+				NULL, 0, 0);
+				xb_mysql_query(mysql_connection,
+					"SET debug_sync='now WAIT_FOR copy_started'", false, true);
+			);
 
 		if (!lock_tables(mysql_connection)) {
 			return(false);
diff --git a/extra/mariabackup/xtrabackup.cc b/extra/mariabackup/xtrabackup.cc
index 04ca6fa11d6..cee9fd81291 100644
--- a/extra/mariabackup/xtrabackup.cc
+++ b/extra/mariabackup/xtrabackup.cc
@@ -669,6 +669,7 @@ static void *dbug_execute_in_new_connection(void *arg)
 }
 
 static pthread_t dbug_alter_thread;
+pthread_t dbug_emulate_ddl_on_intermediate_table_thread;
 
 /*
 Execute query from a new connection, in own thread.
@@ -681,7 +682,7 @@ Execute query from a new connection, in own thread.
 @param expected_errno - if not 0, and query finished with error,
 	expected mysql_errno()
 */
-static void dbug_start_query_thread(
+pthread_t dbug_start_query_thread(
 	const char *query,
 	const char *wait_state,
 	int expected_err,
@@ -693,12 +694,14 @@ static void dbug_start_query_thread(
 	par->expect_err = expected_err;
 	par->expect_errno = expected_errno;
 	par->con =  xb_mysql_connect();
-
-	mysql_thread_create(0, &dbug_alter_thread, nullptr,
+	if (mysql_set_server_option(par->con, MYSQL_OPTION_MULTI_STATEMENTS_ON))
+		die("Can't set multistatement option for query: %s", query);
+	pthread_t result_thread;
+	mysql_thread_create(0, &result_thread, nullptr,
 			    dbug_execute_in_new_connection, par);
 
 	if (!wait_state)
-		return;
+		return result_thread;
 
 	char q[256];
 	snprintf(q, sizeof(q),
@@ -720,7 +723,9 @@ static void dbug_start_query_thread(
 end:
 	msg("query '%s' on connection %lu reached state '%s'", query,
 	mysql_thread_id(par->con), wait_state);
+	return result_thread;
 }
+
 #endif
 
 void mdl_lock_all()
@@ -4663,6 +4668,12 @@ fail_before_log_copying_thread_start:
 		DBUG_EXECUTE_IF("check_mdl_lock_works",
 				pthread_join(dbug_alter_thread, nullptr););
 
+		DBUG_EXECUTE_IF("emulate_ddl_on_intermediate_table",
+			pthread_join(
+				dbug_emulate_ddl_on_intermediate_table_thread,
+				nullptr);
+		);
+
 		if (ok) {
 			backup_finish();
 		}
@@ -4738,6 +4749,12 @@ void backup_fix_ddl(CorruptedPages &corrupted_pages)
 
 	DBUG_MARIABACKUP_EVENT("backup_fix_ddl", {});
 
+	DBUG_EXECUTE_IF("emulate_ddl_on_intermediate_table",
+			xb_mysql_query(mysql_connection,
+				"SET debug_sync='now SIGNAL backup_lock_reset "
+				"WAIT_FOR temp_table_dropped'", false, true);
+			);
+
 	for (space_id_to_name_t::iterator iter = ddl_tracker.tables_in_backup.begin();
 		iter != ddl_tracker.tables_in_backup.end();
 		iter++) {
diff --git a/extra/mariabackup/xtrabackup.h b/extra/mariabackup/xtrabackup.h
index 0d1d3eb5a6b..d785e1345b1 100644
--- a/extra/mariabackup/xtrabackup.h
+++ b/extra/mariabackup/xtrabackup.h
@@ -27,6 +27,12 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA
 #include "changed_page_bitmap.h"
 #include <set>
 
+#ifndef DBUG_OFF
+pthread_t dbug_start_query_thread(const char *query, const char *wait_state,
+                                  int expected_err, int expected_errno);
+extern pthread_t dbug_emulate_ddl_on_intermediate_table_thread;
+#endif /* DBUG_OFF */
+
 struct xb_delta_info_t
 {
 	xb_delta_info_t(ulint page_size, ulint zip_size, ulint space_id)
diff --git a/mysql-test/suite/mariabackup/innodb_ddl_on_intermediate_table.test b/mysql-test/suite/mariabackup/innodb_ddl_on_intermediate_table.test
new file mode 100644
index 00000000000..797d1e799af
--- /dev/null
+++ b/mysql-test/suite/mariabackup/innodb_ddl_on_intermediate_table.test
@@ -0,0 +1,19 @@
+--source include/have_debug.inc
+--source include/have_innodb.inc
+--source include/have_debug_sync.inc
+
+--let $targetdir=$MYSQLTEST_VARDIR/tmp/backup
+--mkdir $targetdir
+
+CREATE TABLE IF NOT EXISTS t1 ( col1 INT, col_text TEXT ) ENGINE = InnoDB;
+ALTER TABLE t1 ADD FULLTEXT KEY `ftidx1` ( col_text );
+
+echo # xtrabackup backup;
+--let _RR_TRACE_DIR=/dev/shm/mbackup.rr
+--disable_result_log
+exec rr record $XTRABACKUP --defaults-file=$MYSQLTEST_VARDIR/my.cnf  --backup --parallel=10  --target-dir=$targetdir --dbug=+d,mariabackup_events,emulate_ddl_on_intermediate_table;
+--enable_result_log
+
+SET debug_sync='RESET';
+rmdir $targetdir;
+DROP TABLE t1;
diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index e637d680973..536b3520a65 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -10887,7 +10887,7 @@ copy_data_between_tables(THD *thd, TABLE *from, TABLE *to,
   }
 
   backup_set_alter_copy_lock(thd, from);
-
+  DEBUG_SYNC(thd, "copy_data_between_tables_after_set_backup_lock");
   alter_table_manage_keys(to, from->file->indexes_are_disabled(), keys_onoff);
 
   from->default_column_bitmaps();
@@ -11178,6 +11178,7 @@ copy_data_between_tables(THD *thd, TABLE *from, TABLE *to,
   cleanup_done= 1;
   to->file->extra(HA_EXTRA_NO_IGNORE_DUP_KEY);
 
+  DEBUG_SYNC(thd, "copy_data_between_tables_before_reset_backup_lock");
   if (backup_reset_alter_copy_lock(thd))
     error= 1;