#At file:///home/anurag/mysqlsrc/mysql-5.1-41305/ based on revid:bernt.johnsen@stripped
2824 Anurag Shekhar 2009-02-26
Bug#41305 server crashes when inserting duplicate row into a merge table
This problem comes while inserting a duplicate row in merge table
without key but the child table has a primary key.
While forming the error message handler tries to locate the key field
which is creating this problem but as there is no key on the merge
table there is a segmentation fault.
modified:
mysql-test/r/merge.result
mysql-test/t/merge.test
storage/myisammrg/ha_myisammrg.cc
per-file messages:
mysql-test/r/merge.result
Updated results with new test for this bug.
mysql-test/t/merge.test
Added new test to test error generated from a key on child table where merge table doesn't have any key.
storage/myisammrg/ha_myisammrg.cc
Added a new check to see if the value of error key is higher than the number of key in merge table and if it is the error key set to MAX_KEY. The error message generation routine treats MAX_KEY as unknown key and doesn't tries to
access this in key_info.
=== modified file 'mysql-test/r/merge.result'
--- a/mysql-test/r/merge.result 2009-02-12 10:25:12 +0000
+++ b/mysql-test/r/merge.result 2009-02-26 10:10:00 +0000
@@ -2103,4 +2103,20 @@ a
UNLOCK TABLES;
# drop the created tables
DROP TABLE t1, t2, t3;
+# insert duplicate value in child table while merge table doesn't have key
+create table t1 (
+col1 int(10),
+primary key (col1)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1;
+create table t2 (
+col1 int(10),
+primary key (col1)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1;
+CREATE TABLE m1 (
+col1 int(10) NOT NULL
+) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 INSERT_METHOD=LAST UNION=(t1,t2);
+insert into m1 (col1) values (1);
+insert into m1 (col1) values (1);
+ERROR 23000: Duplicate entry '' for key '*UNKNOWN*'
+drop table m1, t1, t2;
End of 5.1 tests
=== modified file 'mysql-test/t/merge.test'
--- a/mysql-test/t/merge.test 2009-02-12 10:25:12 +0000
+++ b/mysql-test/t/merge.test 2009-02-26 10:10:00 +0000
@@ -1496,4 +1496,27 @@ UNLOCK TABLES;
--echo # drop the created tables
DROP TABLE t1, t2, t3;
+#
+# Bug #41305 server crashes when inserting duplicate row into a merge table
+#
+--echo # insert duplicate value in child table while merge table doesn't have key
+create table t1 (
+ col1 int(10),
+ primary key (col1)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1;
+
+create table t2 (
+ col1 int(10),
+ primary key (col1)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1;
+
+CREATE TABLE m1 (
+ col1 int(10) NOT NULL
+) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 INSERT_METHOD=LAST UNION=(t1,t2);
+
+insert into m1 (col1) values (1);
+--error ER_DUP_ENTRY
+insert into m1 (col1) values (1);
+
+drop table m1, t1, t2;
--echo End of 5.1 tests
=== modified file 'storage/myisammrg/ha_myisammrg.cc'
--- a/storage/myisammrg/ha_myisammrg.cc 2009-02-12 11:12:07 +0000
+++ b/storage/myisammrg/ha_myisammrg.cc 2009-02-26 10:10:00 +0000
@@ -872,6 +872,15 @@ int ha_myisammrg::info(uint flag)
table->s->crashed= 1;
#endif
stats.data_file_length= mrg_info.data_file_length;
+ if (mrg_info.errkey >= table_share->keys) {
+ /*
+ If value of errkey is higher than the number of keys
+ on the table set errkey to MAX_KEY. This will be
+ treated as unknown key case and error message generator
+ won't try to locate key causing segmentation fault.
+ */
+ mrg_info.errkey= MAX_KEY;
+ }
errkey= mrg_info.errkey;
table->s->keys_in_use.set_prefix(table->s->keys);
stats.mean_rec_length= mrg_info.reclength;
