Server crashes in audit_null_plugin_deinit if audit_null could not create the log file on plugin startup

#4  _IO_new_fclose (fp=0x0) at iofclose.c:57

#5  0x00007f1cfe1f0200 in audit_null_plugin_deinit (arg=0x0) at /data/repo/bzr/5.5/plugin/audit_null/audit_null.c:80

#6  0x0000000000823917 in finalize_audit_plugin (plugin=0x34047a0) at /data/repo/bzr/5.5/sql/sql_audit.cc:452

#7  0x00000000006a691c in plugin_deinitialize (plugin=0x34047a0, ref_check=true) at /data/repo/bzr/5.5/sql/sql_plugin.cc:1170

#8  0x00000000006a7090 in reap_plugins () at /data/repo/bzr/5.5/sql/sql_plugin.cc:1249

#9  0x00000000006ab20a in mysql_install_plugin (thd=0x353b140, name=0x353ef00, dl_arg=0x353ef10) at /data/repo/bzr/5.5/sql/sql_plugin.cc:2157

#10 0x00000000006936ac in mysql_execute_command (thd=0x353b140) at /data/repo/bzr/5.5/sql/sql_parse.cc:4383

#11 0x0000000000698efa in mysql_parse (thd=0x353b140, rawbuf=0x7f1cf40074c8 "install plugin audit_null soname 'adt_null'", length=43, parser_state=0x7f1cfe43c500) at /data/repo/bzr/5.5/sql/sql_parse.cc:5760

#12 0x00000000006840a7 in dispatch_command (command=COM_QUERY, thd=0x353b140, packet=0x35ac771 "install plugin audit_null soname 'adt_null'", packet_length=43) at /data/repo/bzr/5.5/sql/sql_parse.cc:1068

#13 0x0000000000682afd in do_command (thd=0x353b140) at /data/repo/bzr/5.5/sql/sql_parse.cc:794

#14 0x000000000082866f in do_handle_one_connection (thd_arg=0x353b140) at /data/repo/bzr/5.5/sql/sql_connect.cc:1266

#15 0x0000000000827da0 in handle_one_connection (arg=0x353b140) at /data/repo/bzr/5.5/sql/sql_connect.cc:1181

#16 0x0000000000bf9ebf in pfs_spawn_thread (arg=0x3551f60) at /data/repo/bzr/5.5/storage/perfschema/pfs.cc:1015

#17 0x00007f1d09b29e9a in start_thread (arg=0x7f1cfe43d700) at pthread_create.c:308

#18 0x00007f1d08e1dcbd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112

let $MYSQLD_DATADIR= `SELECT @@datadir`;

write_file $MYSQLD_DATADIR/audit_null_tables.log;

test

EOF

system chmod 400 $MYSQLD_DATADIR/audit_null_tables.log;

install plugin audit_null soname 'adt_null';

revision-id: sergii@pisem.net-20130521165635-k9lcq5g95glmrv6r

revno: 3778

branch-nick: 5.5