mariadb/mysql-test/r/func_crypt.result
Alexander Barkov 3a37afec29 MDEV-10306 Wrong results with combination of CONCAT, SUBSTR and CONVERT in subquery
The bug happens because of a combination of unfortunate circumstances:

1. Arguments args[0] and args[2] of Item_func_concat point recursively
(through Item_direct_view_ref's) to the same Item_func_conv_charset.
Both args[0]->args[0]->ref[0] and args[2]->args[0]->ref[0] refer to
this Item_func_conv_charset.

2. When Item_func_concat::args[0]->val_str() is called,
Item_func_conv_charset::val_str() writes its result to
Item_func_conc_charset::tmp_value.

3. Then, for optimization purposes (to avoid copying),
Item_func_substr::val_str() initializes Item_func_substr::tmp_value
to point to the buffer fragment owned by Item_func_conv_charset::tmp_value
Item_func_substr::tmp_value is returned as a result of
Item_func_concat::args[0]->val_str().

4. Due to optimization to avoid memory reallocs,
Item_func_concat::val_str() remembers the result of args[0]->val_str()
in "res" and further uses "res" to collect the return value.

5. When Item_func_concat::args[2]->val_str() is called,
Item_func_conv_charset::tmp_value gets overwritten (see #1),
which effectively overwrites args[0]'s Item_func_substr::tmp_value (see #3),
which effectively overwrites "res" (see #4).

This patch does the following:

a. Changes Item_func_conv_charset::val_str(String *str) to use
   tmp_value and str the other way around. After this change tmp_value
   is used to store a temporary result, while str is used to return the value.
   The fixes the second problem (without SUBSTR):
     SELECT CONCAT(t2,'-',t2) c2
       FROM (SELECT CONVERT(t USING latin1) t2 FROM t1) sub;
   As Item_func_concat::val_str() supplies two different buffers when calling
   args[0]->val_str() and args[2]->val_str(), in the new reduction the result
   created during args[0]->val_str() does not get overwritten by
   args[2]->val_str().

b. Fixing the same problem in val_str() for similar classes

   Item_func_to_base64
   Item_func_from_base64
   Item_func_weight_string
   Item_func_hex
   Item_func_unhex
   Item_func_quote
   Item_func_compress
   Item_func_uncompress
   Item_func_des_encrypt
   Item_func_des_decrypt
   Item_func_conv_charset
   Item_func_reverse
   Item_func_soundex
   Item_func_aes_encrypt
   Item_func_aes_decrypt
   Item_func_buffer

c. Fixing Item_func::val_str_from_val_str_ascii() the same way.
   Now Item_str_ascii_func::ascii_buff is used for temporary value,
   while the parameter passed to val_str() is used to return the result.
   This fixes the same problem when conversion (from ASCII to e.g. UCS2)
   takes place. See the ctype_ucs.test for example queries that returned
   wrong results before the fix.

d. Some Item_func descendand classes had temporary String buffers
   (tmp_value and tmp_str), but did not really use them.
   Removing these temporary buffers from:

   Item_func_decode_histogram
   Item_func_format
   Item_func_binlog_gtid_pos
   Item_func_spatial_collection:

e. Removing Item_func_buffer::tmp_value, because it's not used any more.

f. Renaming Item_func_[un]compress::buffer to "tmp_value",
   for consistency with other classes.

Note, this patch does not fix the following classes
(although they have a similar problem):

   Item_str_conv
   Item_func_make_set
   Item_char_typecast

They have a complex implementations and simple swapping between "tmp_value"
and "str" won't work. These classes will be fixed separately.
2017-06-19 12:45:32 +04:00

126 lines
3.2 KiB
Text

drop table if exists t1;
select length(encrypt('foo', 'ff')) <> 0;
length(encrypt('foo', 'ff')) <> 0
1
create table t1 (name varchar(50), pw varchar(64));
insert into t1 values ('tom', password('my_pass'));
set @pass='my_pass';
select name from t1 where name='tom' and pw=password(@pass);
name
tom
select name from t1 where name='tom' and pw=password(@undefined);
name
drop table t1;
select password('abc');
password('abc')
*0D3CED9BEC10A777AEC23CCC353A8C08A633045E
select password('');
password('')
select old_password('abc');
old_password('abc')
7cd2b5942be28759
select old_password('');
old_password('')
select password('gabbagabbahey');
password('gabbagabbahey')
*B0F99D2963660DD7E16B751EC9EE2F17B6A68FA6
select old_password('idkfa');
old_password('idkfa')
5c078dc54ca0fcca
select length(password('1'));
length(password('1'))
41
select length(encrypt('test'));
length(encrypt('test'))
13
select encrypt('test','aa');
encrypt('test','aa')
aaqPiZY5xR5l.
select old_password(NULL);
old_password(NULL)
NULL
select password(NULL);
password(NULL)
set global old_passwords=on;
select password('');
password('')
select old_password('');
old_password('')
select password('idkfa');
password('idkfa')
*B669C9DAC3AA6F2254B03CDEF8DFDD6B2D1054BA
select old_password('idkfa');
old_password('idkfa')
5c078dc54ca0fcca
set old_passwords=on;
select password('idkfa');
password('idkfa')
5c078dc54ca0fcca
select old_password('idkfa');
old_password('idkfa')
5c078dc54ca0fcca
set global old_passwords=off;
select password('idkfa');
password('idkfa')
5c078dc54ca0fcca
select old_password('idkfa');
old_password('idkfa')
5c078dc54ca0fcca
set old_passwords=off;
select password('idkfa ');
password('idkfa ')
*2DC31D90647B4C1ABC9231563D2236E96C9A2DB2
select password('idkfa');
password('idkfa')
*B669C9DAC3AA6F2254B03CDEF8DFDD6B2D1054BA
select password(' idkfa');
password(' idkfa')
*12B099E56BB7FE8D43C78FD834A9D1D11178D045
select old_password('idkfa');
old_password('idkfa')
5c078dc54ca0fcca
select old_password(' i d k f a ');
old_password(' i d k f a ')
5c078dc54ca0fcca
explain extended select password('idkfa '), old_password('idkfa');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select password('idkfa ') AS `password('idkfa ')`,old_password('idkfa') AS `old_password('idkfa')`
select encrypt('1234','_.');
encrypt('1234','_.')
#
#
# Bug #44767: invalid memory reads in password() and old_password()
# functions
#
CREATE TABLE t1(c1 MEDIUMBLOB);
INSERT INTO t1 VALUES (REPEAT('a', 1024));
SELECT OLD_PASSWORD(c1), PASSWORD(c1) FROM t1;
OLD_PASSWORD(c1) PASSWORD(c1)
77023ffe214c04ff *82E58A2C08AAFE72C8EB523069CD8ADB33F78F58
DROP TABLE t1;
End of 5.0 tests
#
# Start of 10.0 tests
#
#
# MDEV-10306 Wrong results with combination of CONCAT, SUBSTR and CONVERT in subquery
#
SET @save_optimizer_switch=@@optimizer_switch;
SET optimizer_switch='derived_merge=on';
CREATE TABLE t1 (t VARCHAR(32) CHARSET latin1);
INSERT INTO t1 VALUES('abcdefghi');
SELECT CONCAT(t2,'-',t2) c2 FROM (SELECT ENCRYPT(t,'aa') t2 FROM t1) sub;
c2
aaHHlPHAM4sjs-aaHHlPHAM4sjs
DROP TABLE t1;
SET optimizer_switch=@save_optimizer_switch;
#
# End of 10.0 tests
#