Bug #27515 DROP previlege is not required anymore for RENAME TABLE

Description:
From MySQL Manual:

You must also have the ALTER and DROP privileges on the original table, and the CREATE and INSERT privileges on the new table.

http://dev.mysql.com/doc/refman/5.0/en/rename-table.html

This is true only for 4.1 version, in 5.0 and 5.1 it is possible to rename table without DROP privilege.

In 4.1 I got an error:

mysql> rename table tabc to tabc_bk,tabd to tabc,tabc_bk to tabd;
ERROR 1044 (42000): Access denied for user 'usb'@'localhost' to database 'priv_test'

How to repeat:
1. Create a test database and user with SELECT, INSERT, ALTER and CREATE privileges on this database:

mysql> create database priv_test;
Query OK, 1 row affected (0.00 sec)

mysql> grant select, insert, alter, create on `priv\_test`.* to usb@'localhost' identified by 'mysql';
Query OK, 0 rows affected (0.02 sec)

2. Connect as newly created user:

$ ./bin/mysql  -uusb -pmysql priv_test
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.1.17-beta-debug Source distribution

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> select current_user();
+----------------+
| current_user() |
+----------------+
| usb@localhost  |
+----------------+
1 row in set (0.00 sec)

mysql> create table tabc (col1 int);
Query OK, 0 rows affected (0.02 sec)

mysql> create table tabd (col2 int);
Query OK, 0 rows affected (0.05 sec)

mysql> rename table tabc to tabc_bk,tabd to tabc,tabc_bk to tabd;
Query OK, 0 rows affected (0.00 sec)

As you can see user without DROP privilege was able to rename table.

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/24642

ChangeSet@1.2644, 2007-04-17 16:52:50+05:00, ramil@mysql.com +3 -0
  Fix for bug #27515: DROP previlege is not required anymore for RENAME TABLE
  
  Added missed DROP privilege check on the original table for RENAME TABLE command.

Pushed into 4.1.23

Pushed into 5.0.42

Pushed into 5.1.18-beta

Noted in 4.1.23, 5.0.42, 5.1.18 changelogs.

Security fix: The requirement of the DROP privilege for RENAME TABLE
was not being enforced.

merge into mysql-4.1-ndb tree