bzr push into mysql-5.0-bugteam branch (davi:2705 to 2706) Bug#37075

[Davi Arnaut]

 2706 Davi Arnaut	2008-10-15
      Bug#37075: offset of limit clause might be truncated on 32-bits server w/o big tables
      
      The problem is that the offset argument of the limit clause
      might be truncated on a 32-bits server built without big
      tables support. The truncation was happening because the
      original 64-bits long argument was being cast to a 32-bits
      (ha_rows) offset counter.
      
      The solution is to check if the conversing resulted in value
      truncation and if so, the offset is set to the maximum possible
      value that can fit on the type.
modified:
  mysql-test/r/limit.result
  mysql-test/t/limit.test
  sql/sql_lex.cc

 2705 Davi Arnaut	2008-10-14
      Bug#38823: Invalid memory access when a SP statement does wildcard expansion
      
      The problem is that field names constructed due to wild-card
      expansion done inside a stored procedure could point to freed
      memory if the expansion was performed after the first call to
      the stored procedure.
      
      The problem was solved by patch for Bug#38691. The solution
      was to allocate the database, table and field names in the
      in the statement memory instead of table memory.
modified:
  mysql-test/r/sp.result
  mysql-test/t/sp.test
  sql/item.cc

=== modified file 'mysql-test/r/limit.result'
--- a/mysql-test/r/limit.result	2008-02-28 14:34:08 +0000
+++ b/mysql-test/r/limit.result	2008-10-15 21:34:51 +0000
@@ -111,3 +111,6 @@ set @a=-14632475938453979136;
 execute s using @a, @a;
 ERROR HY000: Incorrect arguments to EXECUTE
 End of 5.0 tests
+select 1 as a limit 4294967296,10;
+a
+End of 5.1 tests

=== modified file 'mysql-test/t/limit.test'
--- a/mysql-test/t/limit.test	2008-02-28 14:34:08 +0000
+++ b/mysql-test/t/limit.test	2008-10-15 21:34:51 +0000
@@ -95,3 +95,11 @@ set @a=-14632475938453979136;
 execute s using @a, @a;
 
 --echo End of 5.0 tests
+
+#
+# Bug#37075: offset of limit clause might be truncated to 0 on 32-bits server w/o big tables
+#
+
+select 1 as a limit 4294967296,10;
+
+--echo End of 5.1 tests

=== modified file 'sql/sql_lex.cc'
--- a/sql/sql_lex.cc	2008-10-07 21:34:00 +0000
+++ b/sql/sql_lex.cc	2008-10-15 21:34:51 +0000
@@ -2041,12 +2041,26 @@ st_lex::copy_db_to(char **p_db, uint *p_
 void st_select_lex_unit::set_limit(SELECT_LEX *sl)
 {
   ha_rows select_limit_val;
+  ulonglong val;
 
   DBUG_ASSERT(! thd->stmt_arena->is_stmt_prepare());
-  select_limit_val= (ha_rows)(sl->select_limit ? sl->select_limit->val_uint() :
-                                                 HA_POS_ERROR);
-  offset_limit_cnt= (ha_rows)(sl->offset_limit ? sl->offset_limit->val_uint() :
-                                                 ULL(0));
+  val= sl->select_limit ? sl->select_limit->val_uint() : HA_POS_ERROR;
+  select_limit_val= (ha_rows)val;
+#ifndef BIG_TABLES
+  /*
+    Check for overflow : ha_rows can be smaller then ulonglong if
+    BIG_TABLES is off.
+    */
+  if (val != (ulonglong)select_limit_val)
+    select_limit_val= HA_POS_ERROR;
+#endif
+  val= sl->offset_limit ? sl->offset_limit->val_uint() : ULL(0);
+  offset_limit_cnt= (ha_rows)val;
+#ifndef BIG_TABLES
+  /* Check for truncation. */
+  if (val != (ulonglong)offset_limit_cnt)
+    offset_limit_cnt= HA_POS_ERROR;
+#endif
   select_limit_cnt= select_limit_val + offset_limit_cnt;
   if (select_limit_cnt < select_limit_val)
     select_limit_cnt= HA_POS_ERROR;		// no limit