MDEV-16039 Crash when selecting virtual columns generated using functions with DAYNAME()bb-10.5-nikita-expr-arena

Due to collation specifics an Item tree could change while fixing. Virtual fields.

1. This should be done on the correct query arena, which is table->expr_arena.
2. Doing it once per table open is enough. Furthermore, fixing virtual exprs after open sets the collation to the one definde by `SET NAMES`, which is incorrect: only the native table collation should be used, and it shouldn't be changed after the table is created.

4 files changed, 181 insertions, 42 deletions

diff --git a/mysql-test/suite/gcol/r/gcol_bugfixes.result b/mysql-test/suite/gcol/r/gcol_bugfixes.result
index 3a859116cab..12acb0a9926 100644
--- a/mysql-test/suite/gcol/r/gcol_bugfixes.result
+++ b/mysql-test/suite/gcol/r/gcol_bugfixes.result
@@ -604,3 +604,83 @@ test	gcol_t1	sidea		NEVER	NULL
 test	gcol_t1	sideb		NEVER	NULL
 test	gcol_t1	sidec	VIRTUAL GENERATED	ALWAYS	sqrt(`sidea` * `sidea` + `sideb` * `sideb`)
 DROP TABLE gcol_t1;
+#
+# MDEV-16039 Crash when selecting virtual columns
+# generated using functions with DAYNAME()
+#
+CREATE TABLE t1 (
+suppliersenttoday INT NOT NULL,
+suppliercaptoday CHAR(10) AS (CONCAT('',DAYNAME('2018-04-26')))
+) COLLATE utf8_bin;
+INSERT INTO t1 (suppliersenttoday) VALUES (0);
+INSERT INTO t1 (suppliersenttoday) VALUES (0);
+SELECT * FROM t1;
+suppliersenttoday	suppliercaptoday
+0	Thursday
+0	Thursday
+PREPARE STMT FROM 'INSERT INTO t1 (suppliersenttoday) VALUES (1)';
+CREATE OR REPLACE TABLE t1 (
+suppliersenttoday INT NOT NULL,
+suppliercaptoday CHAR(10) AS (CONCAT('',DAYNAME('2018-04-26')))
+) COLLATE utf8_bin;
+EXECUTE STMT;
+EXECUTE STMT;
+SELECT * FROM t1;
+suppliersenttoday	suppliercaptoday
+1	Thursday
+1	Thursday
+DROP TABLE t1;
+# (duplicate) MDEV-20380 Server crash during update
+CREATE TABLE gafld (
+nuigafld INTEGER NOT NULL,
+ucrgafld VARCHAR(30) COLLATE UTF8_BIN NOT NULL
+DEFAULT SUBSTRING_INDEX(USER(),'@',1)
+);
+EXPLAIN UPDATE gafld SET nuigafld = 0 WHERE nuigafld = 10;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	gafld	ALL	NULL	NULL	NULL	NULL	1	Using where
+EXPLAIN UPDATE gafld SET nuigafld = 0 WHERE nuigafld = 10;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	gafld	ALL	NULL	NULL	NULL	NULL	1	Using where
+DROP TABLE gafld;
+# (duplicate) MDEV-17653 replace into generated columns is unstable
+# Some columns are snipped from the MDEV test and variable is changed
+CREATE TABLE t (
+c0 TIMESTAMP NOT NULL DEFAULT current_timestamp()
+ON UPDATE current_timestamp(),
+c1 DECIMAL(27,25) GENERATED ALWAYS AS (DAYOFMONTH(@timestamp)),
+c4 TIME NOT NULL,
+c8 SMALLINT(6) GENERATED ALWAYS AS
+(CONCAT_WS(CONVERT(C1 USING CP932),
+GET_FORMAT(DATETIME, 'ISO'),
+@@GLOBAL.FLUSH_TIME) <> (c4 = 1)),
+PRIMARY KEY (c4)
+) DEFAULT CHARSET=latin1;
+REPLACE INTO t SET c0 = '2018-06-03 10:31:43', c4 = '02:58:55';
+REPLACE INTO t SET c0 = '2018-06-03 10:31:44', c4 = '02:58:55';
+REPLACE INTO t SET c0 = '2018-06-03 10:31:45', c4 = '02:58:55';
+DROP TABLE t;
+# (duplicate) MDEV-17986 crash when I insert on a table
+CREATE OR REPLACE TABLE t2 (
+number BIGINT(20) NOT NULL,
+lrn BIGINT(20) NOT NULL DEFAULT 0,
+source VARCHAR(15) NOT NULL
+DEFAULT (REVERSE(SUBSTRING_INDEX(REVERSE(user()), '@', 1))),
+PRIMARY KEY (number)
+);
+REPLACE t2(number) VALUES('1');
+REPLACE t2(number) VALUES('1');
+DROP TABLE t2;
+# (duplicate) MDEV-16048 crashing with virtual columns
+SET @save_old_sql_mode= @@sql_mode;
+SET sql_mode='';
+DROP TABLE IF EXISTS t;
+Warnings:
+Note	1051	Unknown table 'test.t'
+CREATE TABLE t (
+A INT AS (UPDATEXML((@@global.date_format), 1, SUBSTRING_INDEX(1, 2, 3)))
+) ENGINE=INNODB;
+INSERT INTO t VALUES();
+INSERT IGNORE INTO t VALUES();
+DROP TABLE t;
+SET sql_mode= @save_old_sql_mode;
diff --git a/mysql-test/suite/gcol/t/gcol_bugfixes.test b/mysql-test/suite/gcol/t/gcol_bugfixes.test
index 5563347a02a..8df41b4fa2f 100644
--- a/mysql-test/suite/gcol/t/gcol_bugfixes.test
+++ b/mysql-test/suite/gcol/t/gcol_bugfixes.test
@@ -564,3 +564,90 @@ SELECT table_schema,table_name,column_name,extra,is_generated,generation_express
 FROM information_schema.columns WHERE table_name='gcol_t1';
 
 DROP TABLE gcol_t1;
+
+--echo #
+--echo # MDEV-16039 Crash when selecting virtual columns
+--echo # generated using functions with DAYNAME()
+--echo #
+
+CREATE TABLE t1 (
+  suppliersenttoday INT NOT NULL,
+  suppliercaptoday CHAR(10) AS (CONCAT('',DAYNAME('2018-04-26')))
+) COLLATE utf8_bin;
+
+INSERT INTO t1 (suppliersenttoday) VALUES (0);
+INSERT INTO t1 (suppliersenttoday) VALUES (0);
+SELECT * FROM t1;
+
+PREPARE STMT FROM 'INSERT INTO t1 (suppliersenttoday) VALUES (1)';
+
+CREATE OR REPLACE TABLE t1 (
+  suppliersenttoday INT NOT NULL,
+  suppliercaptoday CHAR(10) AS (CONCAT('',DAYNAME('2018-04-26')))
+) COLLATE utf8_bin;
+
+EXECUTE STMT;
+EXECUTE STMT;
+SELECT * FROM t1;
+
+DROP TABLE t1;
+
+--echo # (duplicate) MDEV-20380 Server crash during update
+CREATE TABLE gafld (
+  nuigafld INTEGER NOT NULL,
+  ucrgafld VARCHAR(30) COLLATE UTF8_BIN NOT NULL
+           DEFAULT SUBSTRING_INDEX(USER(),'@',1)
+);
+EXPLAIN UPDATE gafld SET nuigafld = 0 WHERE nuigafld = 10;
+EXPLAIN UPDATE gafld SET nuigafld = 0 WHERE nuigafld = 10;
+DROP TABLE gafld;
+
+--echo # (duplicate) MDEV-17653 replace into generated columns is unstable
+--echo # Some columns are snipped from the MDEV test and variable is changed
+CREATE TABLE t (
+  c0 TIMESTAMP NOT NULL DEFAULT current_timestamp()
+                        ON UPDATE current_timestamp(),
+  c1 DECIMAL(27,25) GENERATED ALWAYS AS (DAYOFMONTH(@timestamp)),
+  c4 TIME NOT NULL,
+  c8 SMALLINT(6) GENERATED ALWAYS AS
+                 (CONCAT_WS(CONVERT(C1 USING CP932),
+                            GET_FORMAT(DATETIME, 'ISO'),
+                            @@GLOBAL.FLUSH_TIME) <> (c4 = 1)),
+  PRIMARY KEY (c4)
+) DEFAULT CHARSET=latin1;
+
+REPLACE INTO t SET c0 = '2018-06-03 10:31:43', c4 = '02:58:55';
+REPLACE INTO t SET c0 = '2018-06-03 10:31:44', c4 = '02:58:55';
+REPLACE INTO t SET c0 = '2018-06-03 10:31:45', c4 = '02:58:55';
+
+DROP TABLE t;
+
+--echo # (duplicate) MDEV-17986 crash when I insert on a table
+CREATE OR REPLACE TABLE t2 (
+  number BIGINT(20) NOT NULL,
+  lrn BIGINT(20) NOT NULL DEFAULT 0,
+  source VARCHAR(15) NOT NULL
+                    DEFAULT (REVERSE(SUBSTRING_INDEX(REVERSE(user()), '@', 1))),
+  PRIMARY KEY (number)
+);
+
+REPLACE t2(number) VALUES('1');
+REPLACE t2(number) VALUES('1');
+
+DROP TABLE t2;
+
+
+--echo # (duplicate) MDEV-16048 crashing with virtual columns
+SET @save_old_sql_mode= @@sql_mode;
+SET sql_mode='';
+
+DROP TABLE IF EXISTS t;
+CREATE TABLE t (
+  A INT AS (UPDATEXML((@@global.date_format), 1, SUBSTRING_INDEX(1, 2, 3)))
+) ENGINE=INNODB;
+INSERT INTO t VALUES();
+INSERT IGNORE INTO t VALUES();
+
+DROP TABLE t;
+SET sql_mode= @save_old_sql_mode;
+
diff --git a/sql/sql_base.cc b/sql/sql_base.cc
index 7ac0dcad596..ff9575bb478 100644
--- a/sql/sql_base.cc
+++ b/sql/sql_base.cc
@@ -5388,45 +5388,6 @@ static void mark_real_tables_as_free_for_reuse(TABLE_LIST *table_list)
 }
 
 
-static bool fix_all_session_vcol_exprs(THD *thd, TABLE_LIST *tables)
-{
-  Security_context *save_security_ctx= thd->security_ctx;
-  TABLE_LIST *first_not_own= thd->lex->first_not_own_table();
-  DBUG_ENTER("fix_session_vcol_expr");
-
-  for (TABLE_LIST *table= tables; table && table != first_not_own;
-       table= table->next_global)
-  {
-    TABLE *t= table->table;
-    if (!table->placeholder() && t->s->vcols_need_refixing &&
-         table->lock_type >= TL_WRITE_ALLOW_WRITE)
-    {
-      if (table->security_ctx)
-        thd->security_ctx= table->security_ctx;
-
-      for (Field **vf= t->vfield; vf && *vf; vf++)
-        if (fix_session_vcol_expr(thd, (*vf)->vcol_info))
-          goto err;
-
-      for (Field **df= t->default_field; df && *df; df++)
-        if ((*df)->default_value &&
-            fix_session_vcol_expr(thd, (*df)->default_value))
-          goto err;
-
-      for (Virtual_column_info **cc= t->check_constraints; cc && *cc; cc++)
-        if (fix_session_vcol_expr(thd, (*cc)))
-          goto err;
-
-      thd->security_ctx= save_security_ctx;
-    }
-  }
-  DBUG_RETURN(0);
-err:
-  thd->security_ctx= save_security_ctx;
-  DBUG_RETURN(1);
-}
-
-
 /**
   Lock all tables in a list.
 
@@ -5587,9 +5548,7 @@ bool lock_tables(THD *thd, TABLE_LIST *tables, uint count, uint flags)
     }
   }
 
-  bool res= fix_all_session_vcol_exprs(thd, tables);
-  if (!res)
-    res= thd->decide_logging_format(tables);
+    bool res= thd->decide_logging_format(tables);
 
   DBUG_RETURN(res);
 }
diff --git a/sql/table.cc b/sql/table.cc
index 3b3a1fa6fb0..7a546412abc 100644
--- a/sql/table.cc
+++ b/sql/table.cc
@@ -1263,6 +1263,19 @@ bool parse_vcol_defs(THD *thd, MEM_ROOT *mem_root, TABLE *table,
       goto end;
   }
 
+  for (Field **vf= table->vfield; vf && *vf; vf++)
+    if (fix_session_vcol_expr(thd, (*vf)->vcol_info))
+      goto end;
+
+  for (Field **df= table->default_field; df && *df; df++)
+    if ((*df)->default_value &&
+        fix_session_vcol_expr(thd, (*df)->default_value))
+      goto end;
+
+  for (Virtual_column_info **cc= table->check_constraints; cc && *cc; cc++)
+    if (fix_session_vcol_expr(thd, (*cc)))
+      goto end;
+
   table->find_constraint_correlated_indexes();
 
   res=0;