From 5a5024a6bdd5d33e0add1987b33326e31d4f9c2c Mon Sep 17 00:00:00 2001 From: Sujatha Sivakumar Date: Mon, 23 Sep 2013 12:13:37 +0530 Subject: Bug#17327454:SEMI-SYNC REPLICATION MASTER CRASH WHEN SET RPL_SEMI_SYNC_MASTER_ENABLED OFF. Problem: ======= If master is waiting for a reply from slave, at this time set global rpl_semi_sync_master_enabled=OFF, the master server will crash. Analysis: ======== When master is waiting for a reply from slave, at this time if semi sync is switched off on master, during switch off if active transactions are present the transactions will be cleared and "active_tranxs_" variable will be set to NULL. When the waiting master connection finds that semi sync is switched of it tries to access "active_tranxs_" without checking if the transaction list exists or not. Accessing NULL transaction list causes the crash. Fix: === A check has been added to see a valid list exists before accessing the "active_tranxs_". --- plugin/semisync/semisync_master.cc | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'plugin/semisync') diff --git a/plugin/semisync/semisync_master.cc b/plugin/semisync/semisync_master.cc index 1be876d0f1b..87adbdcae79 100644 --- a/plugin/semisync/semisync_master.cc +++ b/plugin/semisync/semisync_master.cc @@ -752,7 +752,8 @@ int ReplSemiSyncMaster::commitTrx(const char* trx_wait_binlog_name, At this point, the binlog file and position of this transaction must have been removed from ActiveTranx. */ - assert(!active_tranxs_->is_tranx_end_pos(trx_wait_binlog_name, + assert(!getMasterEnabled() || + !active_tranxs_->is_tranx_end_pos(trx_wait_binlog_name, trx_wait_binlog_pos)); /* Update the status counter. */ -- cgit v1.2.1