Bug#54783: optimize table crashes with invalid timestamp default

           value and NO_ZERO_DATE

The problem was that a older version of the error path for a
failed admin statement relied upon a few error conditions being
met in order to access a table handler, the first one being that
the table object pointer was not NULL. Probably due to chance,
in all cases a table object was closed but the reference wasn't
reset, the other conditions didn't evaluate to true. With the
addition of a new check on the error path, the handler started
being dereferenced whenever it was not reset to NULL, causing
problems for code paths which closed the table but didn't reset
the reference.

The solution is to reset the reference whenever a admin statement
fails and the tables are closed.

mysql-test/r/partition_innodb.result

@@ -373,3 +373,21 @@ CREATE TABLE t1 (a INT) ENGINE=InnoDB
 PARTITION BY list(a) (PARTITION p1 VALUES IN (1));
 CREATE INDEX i1 ON t1 (a);
 DROP TABLE t1;
+#
+# Bug#54783: optimize table crashes with invalid timestamp default value and NO_ZERO_DATE
+#
+DROP TABLE IF EXISTS t1;
+CREATE TABLE t1 (a INT, b TIMESTAMP DEFAULT '0000-00-00 00:00:00')
+ENGINE=INNODB PARTITION BY LINEAR HASH (a) PARTITIONS 1;
+SET @old_mode = @@sql_mode;
+SET SESSION sql_mode = 'NO_ZERO_DATE';
+OPTIMIZE TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	optimize	note	Table does not support optimize, doing recreate + analyze instead
+test.t1	optimize	error	Invalid default value for 'b'
+test.t1	optimize	status	Operation failed
+Warnings:
+Warning	1265	Data truncated for column 'b' at row 1
+Error	1067	Invalid default value for 'b'
+SET SESSION sql_mode = @old_mode;
+DROP TABLE t1;

mysql-test/t/partition_innodb.test

@@ -452,3 +452,19 @@ SELECT * FROM t1;
 COMMIT;
 DROP TABLE t1;
 --enable_parsing
+
+--echo #
+--echo # Bug#54783: optimize table crashes with invalid timestamp default value and NO_ZERO_DATE
+--echo #
+
+--disable_warnings
+DROP TABLE IF EXISTS t1;
+--enable_warnings
+
+CREATE TABLE t1 (a INT, b TIMESTAMP DEFAULT '0000-00-00 00:00:00')
+  ENGINE=INNODB PARTITION BY LINEAR HASH (a) PARTITIONS 1;
+SET @old_mode = @@sql_mode;
+SET SESSION sql_mode = 'NO_ZERO_DATE';
+OPTIMIZE TABLE t1;
+SET SESSION sql_mode = @old_mode;
+DROP TABLE t1;

sql/sql_table.cc

@@ -4930,6 +4930,8 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
         */
         if (thd->stmt_da->is_ok())
           thd->stmt_da->reset_diagnostics_area();
+        table->table= NULL;
+        result_code= result_code ? HA_ADMIN_FAILED : HA_ADMIN_OK;
         goto send_result;
       }
     }
@@ -5060,6 +5062,7 @@ send_result_message:
       trans_commit_stmt(thd);
       trans_commit(thd);
       close_thread_tables(thd);
+      table->table= NULL;
       thd->mdl_context.release_transactional_locks();
       if (!result_code) // recreation went ok
       {