Fix for bug #32559: connection hangs on query with name_const

Problem: passing a non-constant name to the NAME_CONST function results in a crash.

Fix: check the NAME_CONST name argument; return fake item type if we got
non-constant argument(s).


mysql-test/r/func_misc.result:
  Fix for bug #32559: connection hangs on query with name_const
    - test result.
mysql-test/t/func_misc.test:
  Fix for bug #32559: connection hangs on query with name_const
    - test case.
sql/item.cc:
  Fix for bug #32559: connection hangs on query with name_const
    - Item_name_const::type() now returns NULL_ITEM if non-constant arguments 
      were used to create the item to avoid wrong type casting.
sql/item.h:
  Fix for bug #32559: connection hangs on query with name_const
    - NAME_CONST name argument checked for invariability.

1 files changed, 11 insertions, 1 deletions

diff --git a/mysql-test/t/func_misc.test b/mysql-test/t/func_misc.test
index 2c34f77b1ff..4870379d69e 100644
--- a/mysql-test/t/func_misc.test
+++ b/mysql-test/t/func_misc.test
@@ -204,5 +204,15 @@ SELECT NAME_CONST('test', 1.0);
 SELECT NAME_CONST('test', -1.0);
 SELECT NAME_CONST('test', 'test');
 
---echo End of 5.0 tests
+#
+# Bug #32559: connection hangs on query with name_const
+#
+CREATE TABLE t1(a INT);
+INSERT INTO t1 VALUES (), (), ();
+--error ER_WRONG_ARGUMENTS
+SELECT NAME_CONST(a, '1') FROM t1;
+--error ER_WRONG_ARGUMENTS
+SET INSERT_ID= NAME_CONST(a, a);
+DROP TABLE t1;
 
+--echo End of 5.0 tests