Bug#17254: Error for DEFINER security on VIEW provides too much info

If a view was created with the DEFINER security and later the definer user
was dropped then a SELECT from the view throws the error message saying that
there is no definer user is registered. This is ok for a root but too much
for a mere user.

Now the st_table_list::prepare_view_securety_context() function reveals
the absence of the definer only to a superuser and throws the 'access denied'
error to others.


mysql-test/t/view_grant.test:
  Added a test case for bug#17254: Error for DEFINER security on VIEW provides too much info
mysql-test/r/view_grant.result:
  Added a test case for bug#17254: Error for DEFINER security on VIEW provides too much info
sql/table.cc:
  Bug#17254: Error for DEFINER security on VIEW provides too much info
  Now the st_table_list::prepare_view_securety_context() function reveals
  the absence of the definer only to a superuser and throws the 'access denied'
  error to others.

1 files changed, 20 insertions, 0 deletions

diff --git a/mysql-test/r/view_grant.result b/mysql-test/r/view_grant.result
index 35e7afc0a7b..422d6c5faaf 100644
--- a/mysql-test/r/view_grant.result
+++ b/mysql-test/r/view_grant.result
@@ -712,3 +712,23 @@ DROP FUNCTION f1;
 DROP VIEW v2;
 DROP VIEW v1;
 DROP USER mysqltest_u1@localhost;
+CREATE DATABASE db17254;
+USE db17254;
+CREATE TABLE t1 (f1 INT);
+INSERT INTO t1 VALUES (10),(20);
+CREATE USER def_17254@localhost;
+GRANT SELECT ON db17254.* TO def_17254@localhost;
+CREATE USER inv_17254@localhost;
+GRANT SELECT ON db17254.t1 TO inv_17254@localhost;
+GRANT CREATE VIEW ON db17254.* TO def_17254@localhost;
+CREATE VIEW v1 AS SELECT * FROM t1;
+DROP USER def_17254@localhost;
+for a user
+SELECT * FROM v1;
+ERROR 42000: SELECT command denied to user 'inv_17254'@'localhost' for table 'v1
+'
+for a superuser
+SELECT * FROM v1;
+ERROR HY000: There is no 'def_17254'@'localhost' registered
+DROP USER inv_17254@localhost;
+DROP DATABASE db17254;