==12672== Thread 18:
==12672== Invalid read of size 1
==12672==    at 0x4A06FD1: memcpy (mc_replace_strmem.c:635)
==12672==    by 0x8B8DE4: strmake_root (my_alloc.c:423)
==12672==    by 0x8B8D95: strdup_root (my_alloc.c:414)
==12672==    by 0x5CC366: Query_arena::strdup(char const*) (sql_class.h:674)
==12672==    by 0x65571E: mysqld_list_processes(THD*, char const*, bool) (sql_show.cc:1834)
==12672==    by 0x5F4DC9: mysql_execute_command(THD*) (sql_parse.cc:3033)
==12672==    by 0x5FB9A6: mysql_parse(THD*, char*, unsigned int, Parser_state*) (sql_parse.cc:5543)
==12672==    by 0x5EFC67: dispatch_command(enum_server_command, THD*, char*, unsigned int) (sql_parse.cc:1034)
==12672==    by 0x5EEF73: do_command(THD*) (sql_parse.cc:771)
==12672==    by 0x6CDA8C: do_handle_one_connection(THD*) (sql_connect.cc:787)
==12672==    by 0x6CD598: handle_one_connection (sql_connect.cc:706)
==12672==    by 0x30E1807760: start_thread (pthread_create.c:301)
==12672==    by 0x1ACF670F: ???
==12672==  Address 0x16198593 is 3 bytes inside a block of size 5 free'd
==12672==    at 0x4A050C7: free (vg_replace_malloc.c:366)
==12672==    by 0x8C0FE7: my_free (my_malloc.c:128)
==12672==    by 0x5D3387: THD::set_db(char const*, unsigned long) (sql_class.h:2626)
==12672==    by 0x5D2078: mysql_change_db_impl(THD*, st_mysql_lex_string*, unsigned long, charset_info_st*) (sql_db.cc:1273)
==12672==    by 0x5D22C0: mysql_change_db(THD*, st_mysql_lex_string const*, bool) (sql_db.cc:1456)
==12672==    by 0x855953: sp_head::execute(THD*, bool) (sp_head.cc:1523)
==12672==    by 0x857256: sp_head::execute_procedure(THD*, List<Item>*) (sp_head.cc:2176)
==12672==    by 0x5F7CC8: mysql_execute_command(THD*) (sql_parse.cc:3960)
==12672==    by 0x5FB9A6: mysql_parse(THD*, char*, unsigned int, Parser_state*) (sql_parse.cc:5543)
==12672==    by 0x5EFC67: dispatch_command(enum_server_command, THD*, char*, unsigned int) (sql_parse.cc:1034)
==12672==    by 0x5EEF73: do_command(THD*) (sql_parse.cc:771)
==12672==    by 0x6CDA8C: do_handle_one_connection(THD*) (sql_connect.cc:787)
==12672==    by 0x6CD598: handle_one_connection (sql_connect.cc:706)
==12672==    by 0x30E1807760: start_thread (pthread_create.c:301)
==12672==    by 0x1ACB570F: ???
==12672== 
==12672== 
==12672== ---- Attach to debugger ? --- [Return/N/n/Y/y/C/c] ---- n