database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-09-02 09:41:40 +03:00
Code Activity

Bug#30882 Dropping a temporary table inside a stored function may cause a server crash

Browse Source 
If a stored function that contains a drop temporary table statement
is invoked by a create temporary table of the same name may cause
a server crash. The problem is that when dropping a table no check
is done to ensure that table is not being used by some outer query
(or outer statement), potentially leaving the outer query with a
reference to a stale (freed) table.

The solution is when dropping a temporary table, always check if
the table is being used by some outer statement as a temporary
table can be dropped inside stored procedures.

The check is performed by looking at the TABLE::query_id value for
temporary tables. To simplify this check and to solve a bug related
to handling of temporary tables in prelocked mode, this patch changes
the way in which this member is used to track the fact that table is
used/unused. Now we ensure that TABLE::query_id is zero for unused
temporary tables (which means that all temporary tables which were
used by a statement should be marked as free for reuse after it's
execution has been completed).
This commit is contained in:
davi@endora.local
2007-11-01 18:52:56 -02:00
parent 6bd9f5c1cb
commit cc007acb78
15 changed files with 431 additions and 83 deletions
Download Patch File Download Diff File Expand all files Collapse all files

74
mysql-test/t/sp-error.test
View File

@@ -2078,10 +2078,6 @@ create function bug20701() returns varchar(25) binary return "test";
create function bug20701() returns varchar(25) return "test";
drop function bug20701;
--echo End of 5.1 tests
#
# Bug#26503 (Illegal SQL exception handler code causes the server to crash)
#
@@ -2237,10 +2233,78 @@ end|
--error ER_SP_CANT_SET_AUTOCOMMIT
create trigger t1
before insert on t2 for each row set password = password('foo');
before insert on t2 for each row set password = password('foo');|
delimiter ;|
#
# Bug#30882 Dropping a temporary table inside a stored function may cause a server crash
#
--disable_warnings
drop function if exists f1;
drop function if exists f2;
drop table if exists t1, t2;
--enable_warnings
delimiter |;
create function f1() returns int
begin
drop temporary table t1;
return 1;
end|
delimiter ;|
--error ER_CANT_REOPEN_TABLE
create temporary table t1 as select f1();
delimiter |;
create function f2() returns int
begin
create temporary table t2 as select f1();
return 1;
end|
delimiter ;|
--error ER_CANT_REOPEN_TABLE
create temporary table t1 as select f2();
drop function f1;
drop function f2;
delimiter |;
create function f1() returns int
begin
drop temporary table t2,t1;
return 1;
end|
create function f2() returns int
begin
create temporary table t2 as select f1();
return 1;
end|
delimiter ;|
--error ER_CANT_REOPEN_TABLE
create temporary table t1 as select f2();
drop function f1;
drop function f2;
create temporary table t2(a int);
select * from t2;
delimiter |;
create function f2() returns int
begin
drop temporary table t2;
return 1;
end|
delimiter ;|
select f2();
drop function f2;
--error ER_BAD_TABLE_ERROR
drop table t2;
--echo End of 5.1 tests
#
# BUG#NNNN: New bug synopsis
#