Race condition in the setsid function in Linux before 2.6.8.1 allows local users to cause a denial of service (crash) and possibly access portions of kernel memory, related to TTY changes, locking, and semaphores.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10647
http://www.securityfocus.com/bid/12598
http://www.redhat.com/support/errata/RHSA-2005-092.html
http://marc.info/?l=full-disclosure&m=110846102231365&w=2
http://linux.bkbits.net:8080/linux-2.6/cset%4041ddda70CWJb5nNL71T4MOlG2sMG8A
http://distro.conectiva.com.br/atualizacoes/index.php?id=a&anuncio=000930