Bug #70618 KILL QUERY kills future queries

Description:
Issuing KILL QUERY sets a thread-specific flag which can trigger killing future queries, if the targeted connection is not currently executing queries:

    session 1> SELECT CONNECTION_ID();
    +-----------------+
    | CONNECTION_ID() |
    +-----------------+
    |          420932 |
    +-----------------+
    1 row in set (0.00 sec)
     
    session 2> KILL QUERY 420932;
    Query OK, 0 rows affected (0.00 sec)
     
    session 1> SELECT SLEEP(10);
    +-----------+
    | SLEEP(10) |
    +-----------+
    |         1 |
    +-----------+
    1 row in set (0.00 sec)
     
    session 2> KILL QUERY 420932;
    Query OK, 0 rows affected (0.00 sec)
     
    session 1> SELECT user, host FROM mysql.user ORDER BY host, user;
    ERROR 1317 (70100): Query execution was interrupted

The documentation as written today does not seem to leave open the possibility that *future* statements are killed:

"KILL QUERY terminates the statement that the connection is *currently* executing, but leaves the connection itself intact." 

How to repeat:
See above, or use following JDBC commands:

		Statement stmt = conn.createStatement();
		stmt.executeQuery("SELECT 1");
		stmt.cancel();
		stmt.executeQuery("SELECT user, host FROM mysql.user ORDER BY host, user");

Suggested fix:
Make thread reset the kill flag at the very start of all command handling, and only terminate commands where KILL QUERY was issued during the execution of said query.

Tested in 5.6.14 and 5.1.62 - same behavior.

related:  http://bugs.mysql.com/bug.php?id=45679

Posted by developer:
 
Fixed in 5.7.1.

Duplicate of Bug#45679. fixed in 5.7.1.