bk commit into 5.0 tree (ramil:1.2108) BUG#18306

[ramil]

Below is the list of changes that have just been committed into a local
5.0 repository of ram. When ram does a push these changes will
be propagated to the main repository and, within 24 hours after the
push, to the public repository.
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ChangeSet
  1.2108 06/03/23 18:09:35 ramil@stripped +3 -0
  Fix for bug #18306: MySQL crashes and restarts using subquery

  sql/opt_range.cc
    1.206 06/03/23 18:09:27 ramil@stripped +12 -3
    Fix for bug #18306: MySQL crashes and restarts using subquery
    Restore thd->mem_root because
    during the cond->val_int() evaluation we can come across a subselect 
    item which may allocate memory on the thd->mem_root and assumes
    all the memory allocated has the same life span as the subselect
    item itself.

  mysql-test/t/subselect.test
    1.116 06/03/23 18:09:27 ramil@stripped +11 -0
    Fix for bug #18306: MySQL crashes and restarts using subquery
    test case

  mysql-test/r/subselect.result
    1.137 06/03/23 18:09:27 ramil@stripped +6 -0
    Fix for bug #18306: MySQL crashes and restarts using subquery
    test case

# This is a BitKeeper patch.  What follows are the unified diffs for the
# set of deltas contained in the patch.  The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User:	ramil
# Host:	myoffice.izhnet.ru
# Root:	/usr/home/ram/work/mysql-5.0

--- 1.205/sql/opt_range.cc	2006-02-25 19:46:26 +04:00
+++ 1.206/sql/opt_range.cc	2006-03-23 18:09:27 +04:00
@@ -3604,9 +3604,18 @@ static SEL_TREE *get_mm_tree(PARAM *para
   /* Here when simple cond */
   if (cond->const_item())
   {
-    if (cond->val_int())
-      DBUG_RETURN(new SEL_TREE(SEL_TREE::ALWAYS));
-    DBUG_RETURN(new SEL_TREE(SEL_TREE::IMPOSSIBLE));
+    /*
+      During the cond->val_int() evaluation we can come across a subselect 
+      item which may allocate memory on the thd->mem_root and assumes 
+      all the memory allocated has the same life span as the subselect 
+      item itself. So we have to restore the thread's mem_root here.
+    */
+    MEM_ROOT *tmp_root= param->mem_root;
+    param->thd->mem_root= param->old_root;
+    tree= cond->val_int() ? new(tmp_root) SEL_TREE(SEL_TREE::ALWAYS) :
+                            new(tmp_root) SEL_TREE(SEL_TREE::IMPOSSIBLE);
+    param->thd->mem_root= tmp_root;
+    DBUG_RETURN(tree);
   }
 
   table_map ref_tables= 0;

--- 1.136/mysql-test/r/subselect.result	2006-03-14 16:33:11 +04:00
+++ 1.137/mysql-test/r/subselect.result	2006-03-23 18:09:27 +04:00
@@ -3163,3 +3163,9 @@ t
 crash1
 crash1
 drop table t1;
+create table t1 (c int, key(c));
+insert into t1 values (1142477582), (1142455969);
+create table t2 (a int, b int);
+insert into t2 values (2, 1), (1, 0);
+delete from t1 where c <= 1140006215 and (select b from t2 where a = 2) = 1;
+drop table t1, t2;

--- 1.115/mysql-test/t/subselect.test	2006-03-14 16:33:11 +04:00
+++ 1.116/mysql-test/t/subselect.test	2006-03-23 18:09:27 +04:00
@@ -2074,3 +2074,14 @@ create table t1( f1 int,f2 int);
 insert into t1 values (1,1),(2,2);
 select tt.t from (select 'crash1' as t, f2 from t1) as tt left join t1 on tt.t = 'crash2' and tt.f2 = t1.f2 where tt.t = 'crash1';
 drop table t1;
+
+#
+# Bug #18306: server crash on delete using subquery.
+#
+
+create table t1 (c int, key(c));                              
+insert into t1 values (1142477582), (1142455969);
+create table t2 (a int, b int);
+insert into t2 values (2, 1), (1, 0);
+delete from t1 where c <= 1140006215 and (select b from t2 where a = 2) = 1;
+drop table t1, t2;