MDEV-8432 Slave cannot replicate signed integer-type values with high bit set to 1

The fix is that if the slave has a different integer size than
the master, then they will assume the master has the same signed/unsigned modifier
as the slave.

This means that one can safely change a coon the slave an int to a bigint
or an unsigned int to an unsigned int.  Changing an unsigned int to an
signed bigint will cause replication failures when the high bit of the
unsigned int is set.

We can't give an error if the signess is different on the master and slave
as the binary log doesn't contain the signess of the column on the master.

mysql-test/suite/rpl/r/rpl_alter.result

@@ -14,4 +14,109 @@ select * from mysqltest.t3;
 n
 45
 drop database mysqltest;
+use test;
+#
+# Test bug where ALTER TABLE MODIFY didn't replicate properly
+#
+create table t1 (a int unsigned primary key, b int);
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(10) unsigned NOT NULL,
+  `b` int(11) DEFAULT NULL,
+  PRIMARY KEY (`a`)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+insert into t1 (a) values (1),((1<<32)-1);
+select * from t1;
+a	b
+1	NULL
+4294967295	NULL
+alter table t1 modify a bigint;
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` bigint(20) NOT NULL DEFAULT '0',
+  `b` int(11) DEFAULT NULL,
+  PRIMARY KEY (`a`)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+select * from t1;
+a	b
+1	NULL
+4294967295	NULL
+alter table t1 modify a int unsigned;
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(10) unsigned NOT NULL DEFAULT '0',
+  `b` int(11) DEFAULT NULL,
+  PRIMARY KEY (`a`)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+select * from t1;
+a	b
+1	NULL
+4294967295	NULL
+alter table t1 modify a bigint unsigned;
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` bigint(20) unsigned NOT NULL DEFAULT '0',
+  `b` int(11) DEFAULT NULL,
+  PRIMARY KEY (`a`)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+select * from t1;
+a	b
+1	NULL
+4294967295	NULL
+use test;
+select * from t1;
+a	b
+1	NULL
+4294967295	NULL
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` bigint(20) unsigned NOT NULL DEFAULT '0',
+  `b` int(11) DEFAULT NULL,
+  PRIMARY KEY (`a`)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+create table t2 (a int unsigned auto_increment primary key, b int);
+show create table t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+  `a` int(10) unsigned NOT NULL AUTO_INCREMENT,
+  `b` int(11) DEFAULT NULL,
+  PRIMARY KEY (`a`)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+alter table t2 modify a bigint;
+show create table t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+  `a` bigint(20) NOT NULL DEFAULT '0',
+  `b` int(11) DEFAULT NULL,
+  PRIMARY KEY (`a`)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+alter table t2 modify a bigint auto_increment;
+show create table t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+  `a` bigint(20) NOT NULL AUTO_INCREMENT,
+  `b` int(11) DEFAULT NULL,
+  PRIMARY KEY (`a`)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+drop table t1,t2;
+#
+# MDEV-8432:  Slave cannot replicate signed integer-type values
+# with high bit set to 1
+# Test replication when we have int on master and bigint on slave
+#
+create table t1 (a int unsigned primary key, b int);
+SET GLOBAL SLAVE_TYPE_CONVERSIONS='ALL_NON_LOSSY';
+alter table t1 modify a bigint unsigned;
+insert into t1 (a) values (1),((1<<32)-1);
+select * from t1;
+a	b
+1	NULL
+4294967295	NULL
+SET GLOBAL SLAVE_TYPE_CONVERSIONS='';
+drop table t1;
 include/rpl_end.inc

mysql-test/suite/rpl/t/rpl_alter.test

@@ -15,4 +15,57 @@ drop database mysqltest;
 sync_slave_with_master;
 
 # End of 4.1 tests
+
+connection master;
+use test;
+
+--echo #
+--echo # Test bug where ALTER TABLE MODIFY didn't replicate properly
+--echo #
+
+create table t1 (a int unsigned primary key, b int);
+show create table t1;
+insert into t1 (a) values (1),((1<<32)-1);
+select * from t1;
+alter table t1 modify a bigint;
+show create table t1;
+select * from t1;
+alter table t1 modify a int unsigned;
+show create table t1;
+select * from t1;
+alter table t1 modify a bigint unsigned;
+show create table t1;
+select * from t1;
+sync_slave_with_master;
+use test;
+select * from t1;
+show create table t1;
+connection master;
+#
+create table t2 (a int unsigned auto_increment primary key, b int);
+show create table t2;
+alter table t2 modify a bigint;
+show create table t2;
+alter table t2 modify a bigint auto_increment;
+show create table t2;
+drop table t1,t2;
+
+--echo #
+--echo # MDEV-8432:  Slave cannot replicate signed integer-type values
+--echo # with high bit set to 1
+--echo # Test replication when we have int on master and bigint on slave
+--echo #
+
+create table t1 (a int unsigned primary key, b int);
+sync_slave_with_master;
+SET GLOBAL SLAVE_TYPE_CONVERSIONS='ALL_NON_LOSSY';
+alter table t1 modify a bigint unsigned;
+connection master;
+insert into t1 (a) values (1),((1<<32)-1);
+sync_slave_with_master;
+select * from t1;
+SET GLOBAL SLAVE_TYPE_CONVERSIONS='';
+connection master;
+drop table t1;
+
 --source include/rpl_end.inc

sql/rpl_utility.cc

@@ -876,6 +876,7 @@ TABLE *table_def::create_conversion_table(THD *thd, Relay_log_info *rli, TABLE *
   {
     Create_field *field_def=
       (Create_field*) alloc_root(thd->mem_root, sizeof(Create_field));
+    bool unsigned_flag= 0;
     if (field_list.push_back(field_def))
       DBUG_RETURN(NULL);
 
@@ -885,8 +886,7 @@ TABLE *table_def::create_conversion_table(THD *thd, Relay_log_info *rli, TABLE *
     uint32 max_length=
       max_display_length_for_field(type(col), field_metadata(col));
 
-    switch(type(col))
-    {
+    switch(type(col)) {
       int precision;
     case MYSQL_TYPE_ENUM:
     case MYSQL_TYPE_SET:
@@ -925,6 +925,18 @@ TABLE *table_def::create_conversion_table(THD *thd, Relay_log_info *rli, TABLE *
       pack_length= field_metadata(col) & 0x00ff;
       break;
 
+    case MYSQL_TYPE_TINY:
+    case MYSQL_TYPE_SHORT:
+    case MYSQL_TYPE_INT24:
+    case MYSQL_TYPE_LONG:
+    case MYSQL_TYPE_LONGLONG:
+      /*
+        As we don't know if the integer was signed or not on the master,
+        assume we have same sign on master and slave.  This is true when not
+        using conversions so it should be true also when using conversions.
+      */
+      unsigned_flag= ((Field_num*) target_table->field[col])->unsigned_flag;
+      break;
     default:
       break;
     }
@@ -932,12 +944,13 @@ TABLE *table_def::create_conversion_table(THD *thd, Relay_log_info *rli, TABLE *
     DBUG_PRINT("debug", ("sql_type: %d, target_field: '%s', max_length: %d, decimals: %d,"
                          " maybe_null: %d, unsigned_flag: %d, pack_length: %u",
                          type(col), target_table->field[col]->field_name,
-                         max_length, decimals, TRUE, FALSE, pack_length));
+                         max_length, decimals, TRUE, unsigned_flag,
+                         pack_length));
     field_def->init_for_tmp_table(type(col),
                                   max_length,
                                   decimals,
                                   TRUE,         // maybe_null
-                                  FALSE,        // unsigned_flag
+                                  unsigned_flag,
                                   pack_length);
     field_def->charset= target_table->field[col]->charset();
     field_def->interval= interval;