Bug #33983 Stored Procedures: wrong end <label> syntax is accepted

• Submitted: 22 Jan 2008 15:16
• Modified: 25 Jan 2008 19:42
• Reporter: Konstantin Osipov (OCA)
• Status: Closed
• Category: MySQL Server: Stored Routines
• Severity: S3 (Non-critical)
• Version: 5.0.54
• OS: Any
• Assigned to: Marc ALFF
• CPU Architecture: Any

[22 Jan 2008 15:16] Konstantin Osipov

Description:
Stored procedures compiler accepts a malformed stored procedure definition.
In particular it allows 'end' statement to end to a label that is not associated
with the corresponding 'begin' statement:

create procedure broken_labels()
begin
  label1:
    begin
      label2:
      begin
        select 1;
      end label1;
    end;
end|

In the example above 'end label1' is syntactically unacceptable, since 
the block that is being ended is associated with a different label.
The code generated in case when there are loops and cursors might be
incorrect as well.

How to repeat:
create procedure broken_labels()
begin
  label1:
    begin
      label2:
      begin
        select 1;
      end label1;
    end;
end|

Suggested fix:
Fix the grammar to not accept malformed procedure definition.

[22 Jan 2008 18:03] Valeriy Kravchuk

Thank you for a bug report. Verified just as described:

mysql> select version();
+------------------------------+
| version()                    |
+------------------------------+
| 5.0.54-enterprise-gpl-nt-log |
+------------------------------+
1 row in set (0.00 sec)

mysql> delimiter //
mysql> create procedure broken_labels()
    -> begin
    ->   label1:
    ->     begin
    ->       label2:
    ->       begin
    ->         select 1;
    ->       end label1;
    ->     end;
    -> end//
Query OK, 0 rows affected (0.06 sec)

[24 Jan 2008 1:31] Marc ALFF

Fixed with Bug#33618

[25 Jan 2008 16:54] Marc ALFF

Pushed into 5.0.56

Pushed into 5.1.24-rc

Pushed into 6.0.5-alpha

with bug#33618

[25 Jan 2008 19:42] Paul DuBois

Noted in 5.0.56, 5.1.24, 6.0.5 changelogs.