Comment 1 for bug 1008278

this bug is repeatable in Percona Server 5.5.24, but can not repeat in Percona Server 5.5.18.

below is the stack

#0 increment_count_by_name (name=0xdfb4f0 "#mysql_system#", role_name=0xdfb4f0 "#mysql_system#", users_or_clients=0xe4c280, thd=0x3f0bc50)
    at /tmp/Percona-Server-5.5.24-rel26.0/sql/sql_connect.cc:468
#1 0x000000000060eee4 in update_global_user_stats (thd=0x3f0bc50, create_user=true, now=1338860077)
    at /tmp/Percona-Server-5.5.24-rel26.0/sql/sql_connect.cc:668
#2 0x00000000005702b5 in mysql_parse (thd=0x3f0bc50, rawbuf=0x3f20ad0 "create database db27", length=66115608, parser_state=0x4a2933d0)
    at /tmp/Percona-Server-5.5.24-rel26.0/sql/sql_parse.cc:5869
#3 0x0000000000741359 in Query_log_event::do_apply_event (this=0x3f0f990, rli=0x3ec3c98, query_arg=0x3f0faa9 "create database db27", q_len_arg=20)
    at /tmp/Percona-Server-5.5.24-rel26.0/sql/log_event.cc:3440
#4 0x0000000000503f3e in apply_event (rli=<optimized out>, this=<optimized out>) at /tmp/Percona-Server-5.5.24-rel26.0/sql/log_event.h:1136
#5 apply_event_and_update_pos (ev=0x3f0f990, thd=<optimized out>, rli=0x3ec3c98) at /tmp/Percona-Server-5.5.24-rel26.0/sql/slave.cc:2401
#6 0x0000000000506527 in exec_relay_log_event (thd=0x3f0bc50, rli=0x3ec3c98) at /tmp/Percona-Server-5.5.24-rel26.0/sql/slave.cc:2561
#7 0x000000000050ac34 in handle_slave_sql (arg=<optimized out>) at /tmp/Percona-Server-5.5.24-rel26.0/sql/slave.cc:3378
#8 0x0000003e638064a7 in start_thread () from /lib64/libpthread.so.0
#9 0x0000003e630d3c2d in clone () from /lib64/libc.so.6
#10 0x0000000000000000 in ?? ()
(gdb) p thd->net.vio
$4 = (Vio *) 0x0

and in function increment_count_by_name, thd->net.vio is used:

 542 if (thd->net.vio->type == VIO_TYPE_SSL)
 543 thread_stats->total_ssl_connections++;
 544 return 0;

this code can be changed like this:
 if ( !thd->slave_thread && thd->net.vio->type == VIO_TYPE_SSL)
    thread_stats->total_ssl_connections++;

because in sql thread, thd->net.vio is always 0x0