Hi, Sergey! On Jun 09, svoj@mariadb.org wrote:

revision-id: b8e26b04d4ac22e29a78bca68e101176b6ef507a parent(s): 08b2e1ae73f6fe055391bf8437b6dff1a889c49c committer: Sergey Vojtovich branch nick: mariadb timestamp: 2015-06-09 13:50:43 +0400 message:

MDEV-363 - Server crashes in intern_plugin_lock on concurrent installing semisync plugin and setting rpl_semi_sync_master_enabled

There was race condition between INSTALL PLUGIN and SET. It was caused by a gap in INSTALL PLUGIN when plugin variables were registered but not fully initialized. Accessing such variables concurrently may reference uninitialized memory, specifically sys_var_pluginvar::plugin.

Fixed by initializing sys_var_pluginvar::plugin early, before variable is registered.

ok to push! Regards, Sergei