WL#3602

Post review changes
the --read-only option is not enforced for the slave thread in replication, or for the SUPER user.


sql/handler.cc:
  Post review changes
  Allowing writes for the slave thread or for SUPER, in read-only mode
sql/lock.cc:
  Post review changes
  Allowing writes for the slave thread or for SUPER, in read-only mode
mysql-test/r/rpl_read_only.result:
  New test
mysql-test/t/rpl_read_only-slave.opt:
  New test
mysql-test/t/rpl_read_only.test:
  New test

mysql-test/r/rpl_read_only.result

+stop slave;
+drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
+reset master;
+reset slave;
+drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
+start slave;
+create table t1(a int) engine=InnoDB;
+create table t2(a int) engine=MyISAM;
+insert into t1 values(1001);
+insert into t2 values(2001);
+set global read_only=1;
+select @@read_only;
+@@read_only
+1
+select * from t1;
+a
+1001
+select * from t2;
+a
+2001
+select @@read_only;
+@@read_only
+0
+select * from t1;
+a
+1001
+select * from t2;
+a
+2001
+set global read_only=0;
+BEGIN;
+insert into t1 values(1002);
+insert into t2 values(2002);
+BEGIN;
+insert into t1 values(1003);
+insert into t2 values(2003);
+set global read_only=1;
+COMMIT;
+COMMIT;
+ERROR HY000: The MySQL server is running with the --read-only option so it cannot execute this statement
+set global read_only=0;
+insert into t1 values(1004);
+insert into t2 values(2004);
+select * from t1;
+a
+1001
+1002
+1004
+select * from t2;
+a
+2001
+2002
+2003
+2004
+select * from t1;
+a
+1001
+1002
+1004
+select * from t2;
+a
+2001
+2002
+2003
+2004
+set global read_only=1;
+select @@read_only;
+@@read_only
+1
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) DEFAULT NULL
+) ENGINE=InnoDB DEFAULT CHARSET=latin1
+show create table t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+  `a` int(11) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+insert into t1 values(1005);
+insert into t2 values(2005);
+select * from t1;
+a
+1001
+1002
+1004
+1005
+select * from t2;
+a
+2001
+2002
+2003
+2004
+2005
+select * from t1;
+a
+1001
+1002
+1004
+1005
+select * from t2;
+a
+2001
+2002
+2003
+2004
+2005
+insert into t1 values(1006);
+ERROR HY000: The MySQL server is running with the --read-only option so it cannot execute this statement
+insert into t2 values(2006);
+ERROR HY000: The MySQL server is running with the --read-only option so it cannot execute this statement
+drop table t1;
+drop table t2;

mysql-test/t/rpl_read_only-slave.opt

+--innodb

mysql-test/t/rpl_read_only.test

+# Test case for BUG #11733
+-- source include/master-slave.inc
+-- source include/have_innodb.inc
+
+# Setting the master readonly :
+# - the variable @@readonly is not replicated on the slave
+
+connect (master2,127.0.0.1,test,,test,$MASTER_MYPORT,);
+connect (slave2,127.0.0.1,test,,test,$SLAVE_MYPORT,);
+
+connection master1;
+
+create table t1(a int) engine=InnoDB;
+create table t2(a int) engine=MyISAM;
+insert into t1 values(1001);
+insert into t2 values(2001);
+
+connection master;
+set global read_only=1;
+
+connection master1;
+select @@read_only;
+select * from t1;
+select * from t2;
+
+sync_slave_with_master;
+select @@read_only;
+select * from t1;
+select * from t2;
+
+# - replication of transactions
+connection master;
+set global read_only=0;
+
+connection master1;
+BEGIN;
+insert into t1 values(1002);
+insert into t2 values(2002);
+
+connection master2;
+BEGIN;
+insert into t1 values(1003);
+insert into t2 values(2003);
+
+connection master;
+set global read_only=1;
+
+connection master1;
+## works even with read_only=1, because master1 is root
+COMMIT;
+
+connection master2;
+--error ER_OPTION_PREVENTS_STATEMENT
+COMMIT;
+
+connection master;
+set global read_only=0;
+
+connection master1;
+insert into t1 values(1004);
+insert into t2 values(2004);
+
+select * from t1;
+select * from t2;
+
+sync_slave_with_master;
+select * from t1;
+select * from t2;
+
+# Setting the slave readonly : replication will pass
+# 
+connection slave1;
+set global read_only=1;
+
+connection slave;
+select @@read_only;
+# Make sure the replicated table is also transactional
+show create table t1;
+# Make sure the replicated table is not transactional
+show create table t2;
+
+connection master;
+insert into t1 values(1005);
+insert into t2 values(2005);
+select * from t1;
+select * from t2;
+
+sync_slave_with_master;
+connection slave;
+select * from t1;
+select * from t2;
+
+# Non root user can not write on the slave
+connection slave2;
+--error ER_OPTION_PREVENTS_STATEMENT
+insert into t1 values(1006);
+--error ER_OPTION_PREVENTS_STATEMENT
+insert into t2 values(2006);
+
+## Cleanup
+connection master;
+drop table t1;
+drop table t2;
+sync_slave_with_master;
+

sql/handler.cc

@@ -693,7 +693,11 @@ int ha_commit_trans(THD *thd, bool all)
       DBUG_RETURN(1);
     }
 
-    if (is_real_trans && opt_readonly)
+    if (   is_real_trans
+        && opt_readonly
+        && ! (thd->security_ctx->master_access & SUPER_ACL)
+        && ! thd->slave_thread
+       )
     {
       my_error(ER_OPTION_PREVENTS_STATEMENT, MYF(0), "--read-only");
       ha_rollback_trans(thd, all);

sql/lock.cc

@@ -151,7 +151,11 @@ MYSQL_LOCK *mysql_lock_tables(THD *thd, TABLE **tables, uint count,
       }
     }
 
-    if (write_lock_used && opt_readonly)
+    if (   write_lock_used
+        && opt_readonly
+        && ! (thd->security_ctx->master_access & SUPER_ACL)
+        && ! thd->slave_thread
+       )
     {
       /*
 	Someone has issued SET GLOBAL READ_ONLY=1 and we want a write lock.