Race condition in do_coredump in signal.c in Linux kernel 2.6 allows local users to cause a denial of service by triggering a core dump in one thread while another thread has a pending SIGSTOP.
http://www.securityfocus.com/bid/15723
http://www.securityfocus.com/archive/1/427981/100/0/threaded
http://www.securityfocus.com/archive/1/419522/100/0/threaded
http://www.securityfocus.com/advisories/9806
http://www.mandriva.com/security/advisories?name=MDKSA-2006:018