The release_one_tty function in drivers/char/tty_io.c in the Linux kernel before 2.6.34-rc4 omits certain required calls to the put_pid function, which has unspecified impact and local attack vectors.
https://bugzilla.redhat.com/show_bug.cgi?id=582076
http://www.vupen.com/english/advisories/2010/1857
http://www.openwall.com/lists/oss-security/2010/04/16/1
http://www.openwall.com/lists/oss-security/2010/04/15/2
http://www.openwall.com/lists/oss-security/2010/04/15/1
http://www.openwall.com/lists/oss-security/2010/04/14/1
http://www.mandriva.com/security/advisories?name=MDVSA-2010:198
http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.34-rc4
http://www.debian.org/security/2010/dsa-2053
http://secunia.com/advisories/40645
http://secunia.com/advisories/39830
http://lists.opensuse.org/opensuse-security-announce/2010-07/msg00006.html