[Thu Jun 06 15:20:04 2013] [error] [client 172.29.165.86] (13)Permission denied: exec of '/var/www/html/bugzilla/index.cgi' failed, referer: http://172.29.165.134/bugzilla/
[Thu Jun 06 15:20:04 2013] [error] [client 172.29.165.86] Premature end of script headers: index.cgi, referer: http://172.29.165.134/bugzilla/

解决方法：

[root@oracle html]# chcon -R -t httpd_sys_content_t /var/www/html/bugzilla/