1berry/MariaDB-server
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

BUG#28971 - ALTER TABLE followed by UPDATE for a CSV table

Browse Source 
make server crash

UPDATE against CSV table may cause server crash or update a table with wrong
values.

CSV can write only a whole row at once. That means it must read all columns,
that it is not going to update, and write them along with updated columns.
But only limited set of columns was read, those that were needed for the
UPDATE query.

With this fix all columns are read in case we're performing an UPDATE.
This commit is contained in:
svoj@mysql.com/april.(none) 2007-06-15 03:22:40 +05:00
parent d122a8caf7
commit 8f5b6ec237
3 changed files with 23 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
mysql-test/r/csv.result
View File

@ -5240,3 +5240,11 @@ CREATE TABLE `bug21328` (
insert into bug21328 values (1,NULL,NULL);
alter table bug21328 engine=myisam;
drop table bug21328;
create table t1(a blob, b int) engine=csv;
insert into t1 values('a', 1);
flush tables;
update t1 set b=2;
select * from t1;
a b
a 2
drop table t1;

11
mysql-test/t/csv.test
View File

@ -1653,3 +1653,14 @@ CREATE TABLE `bug21328` (
insert into bug21328 values (1,NULL,NULL);
alter table bug21328 engine=myisam;
drop table bug21328;
#
# BUG#28971 - ALTER TABLE followed by UPDATE for a CSV table make server
# crash
#
create table t1(a blob, b int) engine=csv;
insert into t1 values('a', 1);
flush tables;
update t1 set b=2;
select * from t1;
drop table t1;

5
storage/csv/ha_tina.cc
View File

@ -590,6 +590,7 @@ int ha_tina::find_current_row(uchar *buf)
int eoln_len;
my_bitmap_map *org_bitmap;
int error;
bool read_all;
DBUG_ENTER("ha_tina::find_current_row");
/*
@ -601,6 +602,8 @@ int ha_tina::find_current_row(uchar *buf)
local_saved_data_file_length, &eoln_len)) == 0)
DBUG_RETURN(HA_ERR_END_OF_FILE);
/* We must read all columns in case a table is opened for update */
read_all= !bitmap_is_clear_all(table->write_set);
/* Avoid asserts in ::store() for columns that are not going to be updated */
org_bitmap= dbug_tmp_use_all_columns(table, table->write_set);
error= HA_ERR_CRASHED_ON_USAGE;
@ -678,7 +681,7 @@ int ha_tina::find_current_row(uchar *buf)
goto err;
}
if (bitmap_is_set(table->read_set, (*field)->field_index))
if (read_all || bitmap_is_set(table->read_set, (*field)->field_index))
(*field)->store(buffer.ptr(), buffer.length(), system_charset_info);
}
next_position= end_offset + eoln_len;