sql_attr_multi query causes "Aborted connection" warning with MariaDB about manticoresearch

[sanikolaev]

MRE

docker run --rm -d --name mariadb -e MYSQL_ROOT_PASSWORD=mysecret -p 9307:3306 mariadb
docker logs -f mariadb 2>&1|grep -qm1 "ready for connections"

cat <<'EOF' > multi.conf
source min {
    type = mysql
    sql_host = 127.0.0.1
    sql_user = root
    sql_pass = mysecret
    sql_port = 9307
    sql_db = test
    sql_query = select id from t
    sql_attr_multi = uint m from query; select 1, 1
}

index idx {
    path = idx
    source = min
}
EOF

mysql -P9307 -h0 -u root -pmysecret -e "create database test"
docker exec -i mariadb mariadb -uroot -pmysecret test < t.sql

indexer -c multi.conf idx

snikolaev@dev2:~$ docker logs mariadb 2>&1|tail -1
2024-07-22  6:43:11 13 [Warning] Aborted connection 13 to db: 'test' user: 'root' host: '172.17.0.1' (Got an error writing communication packets)

t.sql is here

Expected: no Aborted connection.

Reproduced in Manticore 6.3.3 fb447b264@24071413 dev (columnar 2.3.1 42f2b06@24070110) (secondary 2.3.1 42f2b06@24070110) (knn 2.3.1 42f2b06@24070110)