MDEV-15990 versioning: don't allow changes in the past

Author: FooBarrior

mysql-test/suite/versioning/r/misc.result

@@ -57,6 +57,30 @@ insert into t2 (a) values (now()),(now());
 select * from t2 where a in (select row_start from t1);
 a
 drop table t1, t2;
+# MDEV-30046 wrong row targeted with "insert ... on duplicate" and "replace"
+# Don't allow changes from the past
+create or replace table t1 (pk int primary key, i int) with system versioning;
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `pk` int(11) NOT NULL,
+  `i` int(11) DEFAULT NULL,
+  PRIMARY KEY (`pk`)
+) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci WITH SYSTEM VERSIONING
+set timestamp=12345;
+insert t1(pk, i) values(1,3);
+set timestamp=12344;
+delete from t1;
+select pk,i from t1 for system_time all;
+pk	i
+set timestamp=12345;
+insert t1(pk, i) values(1,3);
+set timestamp=12344;
+replace t1(pk, i) values(1,4);
+select pk,i from t1 for system_time all;
+pk	i
+1	4
+drop table t1;
 #
 # End of 10.11 tests
 #

mysql-test/suite/versioning/t/misc.test

@@ -51,6 +51,25 @@ insert into t2 (a) values (now()),(now());
 select * from t2 where a in (select row_start from t1);
 drop table t1, t2;
 
+--echo # MDEV-30046 wrong row targeted with "insert ... on duplicate" and "replace"
+--echo # Don't allow changes from the past
+create or replace table t1 (pk int primary key, i int) with system versioning;
+show create table t1;
+set timestamp=12345;
+insert t1(pk, i) values(1,3);
+set timestamp=12344;
+delete from t1;
+
+select pk,i from t1 for system_time all;
+
+set timestamp=12345;
+insert t1(pk, i) values(1,3);
+set timestamp=12344;
+replace t1(pk, i) values(1,4);
+
+select pk,i from t1 for system_time all;
+drop table t1;
+
 --echo #
 --echo # End of 10.11 tests
 --echo #

sql/sql_delete.cc

@@ -333,7 +333,14 @@ int TABLE::delete_row(bool treat_versioned)
       store_record(this, record[1]);
     }
     vers_update_end();
-    err= file->ha_update_row(record[1], record[0]);
+
+    Field *row_start= vers_start_field();
+    Field *row_end= vers_end_field();
+    // Don't make history row with negative lifetime
+    delete_row= row_start->cmp(row_start->ptr, row_end->ptr) > 0;
+
+    if (likely(!delete_row))
+      err= file->ha_update_row(record[1], record[0]);
     if (unlikely(err))
     {
       /*
@@ -350,11 +357,11 @@ int TABLE::delete_row(bool treat_versioned)
                   || err == HA_ERR_FOREIGN_DUPLICATE_KEY;
       if (!delete_row)
         return err;
-
-      if (!replace)
-        del_buf= record[1];
     }
 
+    if (delete_row)
+      del_buf= record[1];
+
     if (replace)
       restore_record(this, record[2]);
   }