MDEV-31264 Purge trying to access freed secondary index page

- InnoDB purge tries to access aborted secondary index and access
the freed secondary index root page.

mysql-test/suite/parts/r/partition_purge.result

@@ -0,0 +1,26 @@
+CREATE TABLE t1(f1 INT, f2 INT, INDEX(f1))ENGINE=InnoDB
+PARTITION BY LIST(f1) (
+PARTITION p1 VALUES in (1, 2, 3),
+PARTITION p2 VALUES in (4, 5, 6));
+INSERT INTO t1 VALUES(1, 1), (1, 1), (6, 1);
+connect con1,localhost,root,,,;
+START TRANSACTION WITH CONSISTENT SNAPSHOT;
+connect con2,localhost,root,,,;
+SET DEBUG_SYNC="innodb_rollback_inplace_alter_table SIGNAL default_resume WAIT_FOR alter_resume";
+ALTER TABLE t1 ADD UNIQUE INDEX(f1);
+connection default;
+set DEBUG_SYNC="now WAIT_FOR default_resume";
+SET DEBUG_SYNC="innodb_row_update_for_mysql_begin SIGNAL alter_resume WAIT_FOR alter_finish";
+DELETE FROM t1;
+connection con2;
+ERROR 23000: Duplicate entry '1' for key 'f1_2'
+SET DEBUG_SYNC="now SIGNAL alter_finish";
+connection default;
+connection con1;
+commit;
+connection default;
+disconnect con1;
+disconnect con2;
+InnoDB		0 transactions not purged
+drop table t1;
+SET DEBUG_SYNC=reset;

mysql-test/suite/parts/t/partition_purge.opt

@@ -0,0 +1 @@
+--innodb_purge_threads=1

mysql-test/suite/parts/t/partition_purge.test

@@ -0,0 +1,37 @@
+--source include/have_innodb.inc
+--source include/have_partition.inc
+--source include/have_debug.inc
+--source include/have_debug_sync.inc
+
+CREATE TABLE t1(f1 INT, f2 INT, INDEX(f1))ENGINE=InnoDB
+                PARTITION BY LIST(f1) (
+                        PARTITION p1 VALUES in (1, 2, 3),
+                        PARTITION p2 VALUES in (4, 5, 6));
+INSERT INTO t1 VALUES(1, 1), (1, 1), (6, 1);
+connect(con1,localhost,root,,,);
+START TRANSACTION WITH CONSISTENT SNAPSHOT;
+
+connect(con2,localhost,root,,,);
+SET DEBUG_SYNC="innodb_rollback_inplace_alter_table SIGNAL default_resume WAIT_FOR alter_resume";
+send ALTER TABLE t1 ADD UNIQUE INDEX(f1);
+
+connection default;
+set DEBUG_SYNC="now WAIT_FOR default_resume";
+SET DEBUG_SYNC="innodb_row_update_for_mysql_begin SIGNAL alter_resume WAIT_FOR alter_finish";
+send DELETE FROM t1;
+
+connection con2;
+--error ER_DUP_ENTRY
+reap;
+SET DEBUG_SYNC="now SIGNAL alter_finish";
+
+connection default;
+reap;
+connection con1;
+commit;
+connection default;
+disconnect con1;
+disconnect con2;
+--source ../../innodb/include/wait_all_purged.inc
+drop table t1;
+SET DEBUG_SYNC=reset;

storage/innobase/row/row0purge.cc

@@ -615,6 +615,8 @@ row_purge_del_mark(
       const auto type= node->index->type;
       if (type & (DICT_FTS | DICT_CORRUPT))
         continue;
+      if (node->index->online_status > ONLINE_INDEX_CREATION)
+        continue;
       if (UNIV_UNLIKELY(DICT_VIRTUAL & type) && !node->index->is_committed() &&
           node->index->has_new_v_col())
         continue;
@@ -767,6 +769,11 @@ row_purge_upd_exist_or_extern_func(
 			continue;
 		}
 
+		if (node->index->online_status
+		    > ONLINE_INDEX_CREATION) {
+			continue;
+		}
+
 		if (row_upd_changes_ord_field_binary(node->index, node->update,
 						     thr, NULL, NULL)) {
 			/* Build the older version of the index entry */