From b996aabd1a79d9f8d71e75faea2b29c603b1472b Mon Sep 17 00:00:00 2001
From: Dave Gosselin <dave.gosselin@mariadb.com>
Date: Thu, 12 Jun 2025 14:35:23 -0400
Subject: [PATCH] MDEV-36997 Assertion failed in ha_tina::delete_row on multi
 delete

Multi-delete code invokes ha_rnd_end after applying deferred deletes, following
the pattern as in multi-update.

The CSV engine batches deletes made via calls to delete_row, then applies them
all at once during ha_rnd_end.  For each row batched, the CSV engine decrements
an internal counter of the total rows in the table.  The multi-delete code was
not calling ha_rnd_end, so this internal counter was not consistent with the
total number of rows in the table, triggering the assertion.
---
 mysql-test/main/delete_multi_order_by.result | 34 ++++++++++++++++++++
 mysql-test/main/delete_multi_order_by.test   | 28 ++++++++++++++++
 sql/sql_delete.cc                            |  4 +++
 3 files changed, 66 insertions(+)

diff --git a/mysql-test/main/delete_multi_order_by.result b/mysql-test/main/delete_multi_order_by.result
index 20f3f1b3d30..656090040ef 100644
--- a/mysql-test/main/delete_multi_order_by.result
+++ b/mysql-test/main/delete_multi_order_by.result
@@ -391,3 +391,37 @@ id	v
 select * from t3;
 id	v
 drop table t1, t2, t3;
+#
+# Begin 11.8 tests
+#
+#
+# MDEV-36997 Assertion failed in ha_tina::delete_row on multi delete
+#
+SET sql_mode='';
+CREATE TABLE t1 (v INT (1) NOT NULL) ENGINE=CSV;
+INSERT INTO t1 SELECT 1 away;
+SELECT COUNT(*) from t1;
+COUNT(*)
+1
+DELETE FROM a3,a1 USING t1 AS a1 JOIN t1 AS a2 JOIN t1 AS a3;
+SELECT COUNT(*) from t1;
+COUNT(*)
+0
+DROP TABLE t1;
+SET sql_mode='';
+CREATE TABLE t1 (v VECTOR (1) NOT NULL) ENGINE=CSV;
+INSERT INTO t1 SELECT 1 away;
+Warnings:
+Warning	4078	Cannot cast 'int' as 'vector' in assignment of `test`.`t1`.`v`
+Warning	1292	Incorrect vector value: '1' for column `test`.`t1`.`v` at row 1
+SELECT COUNT(*) from t1;
+COUNT(*)
+1
+DELETE FROM a3,a1 USING t1 AS a1 JOIN t1 AS a2 JOIN t1 AS a3;
+SELECT COUNT(*) from t1;
+COUNT(*)
+0
+DROP TABLE t1;
+#
+# End 11.8 tests
+#
diff --git a/mysql-test/main/delete_multi_order_by.test b/mysql-test/main/delete_multi_order_by.test
index 801d324c61b..c2c2b281553 100644
--- a/mysql-test/main/delete_multi_order_by.test
+++ b/mysql-test/main/delete_multi_order_by.test
@@ -3,6 +3,7 @@
 #
 
 --source include/have_innodb.inc
+--source include/have_csv.inc
 
 create table t1 (id int primary key, v int);
 create table t2 (id int primary key, v int);
@@ -203,3 +204,30 @@ select * from t2;
 select * from t3;
 
 drop table t1, t2, t3;
+
+--echo #
+--echo # Begin 11.8 tests
+--echo #
+
+--echo #
+--echo # MDEV-36997 Assertion failed in ha_tina::delete_row on multi delete
+--echo #
+SET sql_mode='';
+CREATE TABLE t1 (v INT (1) NOT NULL) ENGINE=CSV;
+INSERT INTO t1 SELECT 1 away;
+SELECT COUNT(*) from t1;
+DELETE FROM a3,a1 USING t1 AS a1 JOIN t1 AS a2 JOIN t1 AS a3;
+SELECT COUNT(*) from t1;
+DROP TABLE t1;
+
+SET sql_mode='';
+CREATE TABLE t1 (v VECTOR (1) NOT NULL) ENGINE=CSV;
+INSERT INTO t1 SELECT 1 away;
+SELECT COUNT(*) from t1;
+DELETE FROM a3,a1 USING t1 AS a1 JOIN t1 AS a2 JOIN t1 AS a3;
+SELECT COUNT(*) from t1;
+DROP TABLE t1;
+
+--echo #
+--echo # End 11.8 tests
+--echo #
diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc
index cc8eb6082ae..fcf024a1f4c 100644
--- a/sql/sql_delete.cc
+++ b/sql/sql_delete.cc
@@ -1647,6 +1647,10 @@ int multi_delete::rowid_table_deletes(TABLE *table, bool ignore)
 err:
   if (err_table)
     err_table->file->print_error(local_error,MYF(ME_FATAL));
+  if (tmp_table->file->inited == handler::init_stat::RND)
+    tmp_table->file->ha_rnd_end();
+  if (table->file->inited == handler::init_stat::RND)
+    table->file->ha_rnd_end();
   DBUG_RETURN(local_error);
 }