Merge lp:~gl-az/percona-server/ST-29716-bug1135097-5.6 into lp:percona-server/5.6

[George Ormond Lorch III]

Fix for upstream bugs.mysql.com/bug.php?id=68490 and bugs.launchpad.net/percona-server/+bug/1135097

When reconnecting to the master, the mysql client library in sql-common/client.c::mysql_reconnect creates a new 'tmp' MYSQL* with all default values (overwriting the MYSQL::net.max_packet_size with default). It then copies the contents of the tmp back into the passed in MYSQL*.

This causes issues with the slave connection when reconnecting because: 1) The code in handle_slave_io(...) is not setting the mysql->option.max_allowed_packet but directly manipulating the mysql->net.max_packet_size which gets reset when the connection is recreated as described above, and 2) the mysql->options.max_allowed_packet is being set in the top of handle_slave_io(...) and not in connect_to_master(...) where all other client options are being set for the connection and thus is not always properly set to the correct value depending on the reason for reconnecting.

The fix is somewhat simple, in sql/slave.cc, moves lines 4017-4027 from handle_slave_io to line 6640 and change:
  mysql->net.max_packet_size= thd->net.max_packet_size+= MAX_LOG_EVENT_HEADER;
to
  mysql->options.max_allowed_packet= thd->net.max_packet_size+= MAX_LOG_EVENT_HEADER;

Added test suite/rpl/t/rpl_packet_bug68490.test

Fix for upstream bugs.mysql.com/bug.php?id=68490 and bugs.launchpad.net/percona-server/+bug/1135097

When reconnecting to the master, the mysql client library in sql-common/client.c::mysql_reconnect creates a new 'tmp' MYSQL* with all default values (overwriting the MYSQL::net.max_packet_size with default). It then copies the contents of the tmp back into the passed in MYSQL*.

This causes issues with the slave connection when reconnecting because: 1) The code in handle_slave_io(...) is not setting the mysql->option.max_allowed_packet but directly manipulating the mysql->net.max_packet_size which gets reset when the connection is recreated as described above, and 2) the mysql->options.max_allowed_packet is being set in the top of handle_slave_io(...) and not in connect_to_master(...) where all other client options are being set for the connection and thus is not always properly set to the correct value depending on the reason for reconnecting.

The fix is somewhat simple, in sql/slave.cc, moves lines 4017-4027 from handle_slave_io to line 6640 and change:
  mysql->net.max_packet_size= thd->net.max_packet_size+= MAX_LOG_EVENT_HEADER;
to
  mysql->options.max_allowed_packet= thd->net.max_packet_size+= MAX_LOG_EVENT_HEADER;

Added test suite/rpl/t/rpl_packet_bug68490.test

[George Ormond Lorch III (gl-az)]

http://jenkins.percona.com/view/PS%205.6/job/percona-server-5.6-param/50/

[Stewart Smith (stewart)]

review: Approve

=== added file 'Percona-Server/mysql-test/suite/rpl/r/rpl_bug68490.result'
--- Percona-Server/mysql-test/suite/rpl/r/rpl_bug68490.result	1970-01-01 00:00:00 +0000
+++ Percona-Server/mysql-test/suite/rpl/r/rpl_bug68490.result	2013-03-07 19:06:28 +0000
@@ -0,0 +1,11 @@
+include/master-slave.inc
+Warnings:
+Note	####	Sending passwords in plain text without SSL/TLS is extremely insecure.
+Note	####	Storing MySQL user name or password information in the master.info repository is not secure and is therefore not recommended. Please see the MySQL Manual for more about this issue and possible alternatives.
+[connection master]
+DROP TABLE IF EXISTS t1;
+CREATE TABLE t1(id INT AUTO_INCREMENT PRIMARY KEY, payload MEDIUMBLOB NOT NULL);
+include/rpl_restart_server.inc [server_number=1]
+INSERT INTO t1(payload) VALUES(REPEAT('a',1468872));
+DROP TABLE t1;
+include/rpl_end.inc

=== added file 'Percona-Server/mysql-test/suite/rpl/t/rpl_bug68490-master.opt'
--- Percona-Server/mysql-test/suite/rpl/t/rpl_bug68490-master.opt	1970-01-01 00:00:00 +0000
+++ Percona-Server/mysql-test/suite/rpl/t/rpl_bug68490-master.opt	2013-03-07 19:06:28 +0000
@@ -0,0 +1,1 @@
+--max-allowed_packet=4M

=== added file 'Percona-Server/mysql-test/suite/rpl/t/rpl_bug68490-slave.opt'
--- Percona-Server/mysql-test/suite/rpl/t/rpl_bug68490-slave.opt	1970-01-01 00:00:00 +0000
+++ Percona-Server/mysql-test/suite/rpl/t/rpl_bug68490-slave.opt	2013-03-07 19:06:28 +0000
@@ -0,0 +1,2 @@
+--max_allowed_packet=1M
+--slave_max_allowed_packet=1G

=== added file 'Percona-Server/mysql-test/suite/rpl/t/rpl_bug68490.test'
--- Percona-Server/mysql-test/suite/rpl/t/rpl_bug68490.test	1970-01-01 00:00:00 +0000
+++ Percona-Server/mysql-test/suite/rpl/t/rpl_bug68490.test	2013-03-07 19:06:28 +0000
@@ -0,0 +1,21 @@
+--source include/have_binlog_format_row.inc 
+--source include/master-slave.inc
+
+--disable_warnings
+DROP TABLE IF EXISTS t1;
+sync_slave_with_master;
+--enable_warnings
+
+connection master;
+CREATE TABLE t1(id INT AUTO_INCREMENT PRIMARY KEY, payload MEDIUMBLOB NOT NULL);
+
+--let $rpl_server_number= 1
+--source include/rpl_restart_server.inc
+
+INSERT INTO t1(payload) VALUES(REPEAT('a',1468872));
+sync_slave_with_master;
+
+connection master;
+DROP TABLE t1;
+
+--source include/rpl_end.inc 

=== modified file 'Percona-Server/sql/rpl_slave.cc'
--- Percona-Server/sql/rpl_slave.cc	2013-03-05 12:46:43 +0000
+++ Percona-Server/sql/rpl_slave.cc	2013-03-07 19:06:28 +0000
@@ -4015,16 +4015,6 @@
                           mi->get_user(), mi->host, mi->port,
 			  mi->get_io_rpl_log_name(),
 			  llstr(mi->get_master_log_pos(), llbuff));
-  /*
-    Assign the max_packet_size with the bigger one of the values of
-    'max_packet_size' and 'opt_binlog_rows_event_max_size'. So that
-    slave I/O thread can replicate large row event from master.
-    Adding MAX_LOG_EVENT_HEADER_LEN to the max_packet_size on the I/O
-    thread, since a replication event can become this much larger than
-    the corresponding packet (query) sent from client to master.
-  */
-    thd->net.max_packet_size= slave_max_allowed_packet;
-    mysql->net.max_packet_size= thd->net.max_packet_size+= MAX_LOG_EVENT_HEADER;
   }
   else
   {
@@ -6647,6 +6637,16 @@
   mysql_options(mysql, MYSQL_SET_CHARSET_NAME, default_charset_info->csname);
   /* This one is not strictly needed but we have it here for completeness */
   mysql_options(mysql, MYSQL_SET_CHARSET_DIR, (char *) charsets_dir);
+  /*
+    Assign the max_packet_size with the bigger one of the values of
+    'max_packet_size' and 'opt_binlog_rows_event_max_size'. So that
+    slave I/O thread can replicate large row event from master.
+    Adding MAX_LOG_EVENT_HEADER_LEN to the max_packet_size on the I/O
+    thread, since a replication event can become this much larger than
+    the corresponding packet (query) sent from client to master.
+  */
+  thd->net.max_packet_size= slave_max_allowed_packet;
+  mysql->options.max_allowed_packet= thd->net.max_packet_size+= MAX_LOG_EVENT_HEADER;
 
   if (mi->is_start_plugin_auth_configured())
   {