Description:
Hello, I found a bug in 8.0.35-cluster version of MYSQL cluster. It will cause the current mysql service to crash.
It's very similar to bug #114773, and I doubt it's the same piece of code that's at fault.
The detail is as follow.
OS version and name:
Ubuntu 22.04.3 LTS (Jammy Jellyfish)
Linux eb1f47b08982 6.5.11-8-pve #1 SMP PREEMPT_DYNAMIC PMX 6.5.11-8 (2024-01-30T12:27Z) x86_64 x86_64 x86_64 GNU/Linux
Poc:
```
select
subq_1.c0 as c0,
subq_1.c0 as c1,
case when (false)
and (((false)
or (false))
and (true)) then subq_1.c0 else subq_1.c0 end
as c2,
subq_1.c0 as c3,
subq_1.c0 as c4,
subq_1.c0 as c5,
subq_1.c0 as c6
from
(select
ref_0.column6 as c0
from
mytest90.test3 as ref_0
right join (select
ref_2.column7 as c0,
ref_2.column6 as c1,
ref_1.column5 as c2,
ref_1.column1 as c3,
ref_1.column1 as c4,
ref_1.column5 as c5
from
mytest90.test7 as ref_1
left join mytest90.test7 as ref_2
on ((ref_2.column6 is not NULL)
and ((ref_2.column6 is not NULL)
or (false)))
where (((false)
or (false))
and (EXISTS (
select
ref_1.column6 as c0,
ref_3.column1 as c1,
ref_3.column1 as c2,
ref_2.column2 as c3
from
mytest90.test6 as ref_3
where true
limit 185)))
or (ref_1.column1 is NULL)
limit 89) as subq_0
on ((false)
and (false))
where ref_0.column1 is NULL
limit 116) as subq_1
where false
limit 149;
```
It manifests itself in this way:
```
ERROR 2013 (HY000): Lost connection to MySQL server during query
No connection. Trying to reconnect...
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/usr/local/mysql-cluster/sock/mysql.sock' (111)
ERROR:
Can't connect to the server
```
Architecture Information:
'''
[NDBD DEFAULT]
NoOfReplicas =2
DataMemory = 512M
IndexMemory = 64M
[NDB_MGMD]
NodeId=1
hostname =192.172.10.8
datadir =/var/lib/mysql-cluster
[NDBD]
NodeId =2
hostname =192.172.10.9
datadir =/usr/local/mysql-cluster/data
NodeGroup=0
[NDBD]
NodeId =3
hostname =192.172.10.10
datadir =/usr/local/mysql-cluster/data
NodeGroup=1
[NDBD]
NodeId =4
hostname =192.172.10.11
datadir =/usr/local/mysql-cluster/data
NodeGroup=0
[NDBD]
NodeId =5
hostname =192.172.10.12
datadir =/usr/local/mysql-cluster/data
NodeGroup=1
[mysqld]
NodeId =6
hostname =192.172.10.9
[mysqld]
NodeId =7
hostname =192.172.10.10
[mysqld]
NodeId =8
hostname =192.172.10.11
[mysqld]
NodeId =9
hostname =192.172.10.12
'''
Attempted and successfully reproduced!
How to repeat:
Importing the database file I give later, and then executing Poc
Suggested fix:
The reason this bug is strange, and the reason why I say he and bug #114773 are similar rather than equivalent, is that he is a SELECT statement, not a DELETE statement that would make changes to the data that would require synchronized operations, so it's possible that he's causing the mysql service to crash for a different reason.
