MySQL Bugs: #3183: UPDATE or DELETE query with index_merge OR condition can cause error or crash

Bug #3183	UPDATE or DELETE query with index_merge OR condition can cause error or crash
Submitted:	15 Mar 2004 22:09	Modified:	16 Mar 2004 15:45
Reporter:	Sergey Petrunya	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server	Severity:	S2 (Serious)
Version:	5.0-bk	OS:
Assigned to:	Sergey Petrunya	CPU Architecture:	Any

Description:
UPDATE or DELETE query with index_merge OR condition can fail with "Got error 124 from storage engine" message or server crash.

How to repeat:
Apply the following patch to mysql-test/t/index_merge.test

===== t/index_merge.test 1.3 vs edited =====
47a48,52
> create table t1 like t0;
> insert into t1 select * from t0;
> delete from t1 where key1 < 3 or key2 > 1022;
> drop table t1;
> 

then run t/index_merge.test.

Suggested fix:
QUICK_SELECT_I::reset() function is never called for quick selects in UPDATE and DELETE queries. This is ok for range quick selects. For index_merge quick select calling get_next() without prior reset() call causes use of initialized data with error or crash.

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