Bug #76093 show create user doesn\'t work with 5.6 and 5.5 clients
Submitted: 2 Mar 2015 11:41 Modified: 10 Mar 2015 17:59
Reporter: Ramana Yeruva Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: Command-line Clients Severity:S3 (Non-critical)
Version:5.7.6 OS:Any
Assigned to: CPU Architecture:Any

[2 Mar 2015 11:41] Ramana Yeruva
Description:
create user in 5.7.6 and execute show create user command with that user and any user in 5.6 or 5.5 mysql client
Observe "ERROR 2027 (HY000): Malformed packet" error

How to repeat:
./mysqld -uroot --initialize-insecure --basedir=../ --datadir=./data
./mysqld -uroot --basedir=../ --datadir=./data --gdb &
mysql> grant all on *.* to ramana@localhost identified by 'ramana';
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> show warnings\g
+---------+------+------------------------------------------------------------------------------------------------------------------------------------+
| Level   | Code | Message                                                                                                                            |
+---------+------+------------------------------------------------------------------------------------------------------------------------------------+
| Warning | 1287 | Using GRANT for creating new user is deprecated and will be removed in future release. Create new user with CREATE USER statement. |
+---------+------+------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

[lroot@vitro77 bin]# ./mysql -V
./mysql  Ver 14.14 Distrib 5.6.24, for linux-glibc2.5 (x86_64) using  EditLine wrapper
[lroot@vitro77 bin]# ./mysql -uramana -pramana --socket=/tmp/mysql.sock
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.7.6-m16-enterprise-commercial-advanced MySQL Enterprise Server - Advanced Edition (Commercial)
Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> show create user ramana@localhost\G
ERROR 2027 (HY000): Malformed packet

same is observed with 5.5 client too
[10 Mar 2015 17:59] Paul Dubois
Noted in 5.7.7, 5.8.0 changelogs.

SHOW CREATE USER did not work for clients older than MySQL 5.7.