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Bug#38999 valgrind warnings for update statement in function compare_record()

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Valgrind warning happpens because of uninitialized null bytes.
In row_sel_push_cache_row_for_mysql() function we fill fetch cache
with necessary field values, row_sel_store_mysql_rec() is called
for this and leaves null bytes untouched.
Later row_sel_pop_cached_row_for_mysql() rewrites table record
buffer with uninited null bytes. We can see the problem from the
test case:
At 'SELECT...' we call row_sel_push...->row_sel_store...->row_sel_pop_cached...
chain which rewrites table->record[0] buffer with uninitialized null bytes.
When we call 'UPDATE...' statement, compare_record uses this buffer and
valgrind warning occurs.
The fix is to init null bytes with default values.
This commit is contained in:
Sergey Glukhov
2010-06-09 16:07:34 +04:00
parent d8aada889e
commit d2db80c8d4
4 changed files with 31 additions and 4 deletions
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12
mysql-test/suite/innodb/r/innodb_mysql.result
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@ -2378,4 +2378,16 @@ SELECT SECOND(c)-@bug47453 FROM t1 JOIN t2 ON d=a;
SECOND(c)-@bug47453
0
DROP TABLE t1, t2;
#
# Bug#38999 valgrind warnings for update statement in function compare_record()
#
CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE=InnoDB;
CREATE TABLE t2 (a INT PRIMARY KEY) ENGINE=InnoDB;
INSERT INTO t1 values (1),(2),(3),(4),(5);
INSERT INTO t2 values (1);
SELECT * FROM t1 WHERE a = 2;
a
2
UPDATE t1,t2 SET t1.a = t1.a + 100 WHERE t1.a = 1;
DROP TABLE t1,t2;
End of 5.1 tests