The copy_semid_to_user function in ipc/sem.c in the Linux kernel before 2.6.36 does not initialize a certain structure, which allows local users to obtain potentially sensitive information from kernel stack memory via a (1) IPC_INFO, (2) SEM_INFO, (3) IPC_STAT, or (4) SEM_STAT command in a semctl system call.
https://bugzilla.redhat.com/show_bug.cgi?id=648673
http://www.vupen.com/english/advisories/2011/0375
http://www.vupen.com/english/advisories/2011/0298
http://www.vupen.com/english/advisories/2011/0168
http://www.vupen.com/english/advisories/2011/0124
http://www.vupen.com/english/advisories/2011/0024
http://www.vupen.com/english/advisories/2011/0012
http://www.vmware.com/security/advisories/VMSA-2011-0012.html
http://www.spinics.net/lists/mm-commits/msg80234.html
http://www.securityfocus.com/bid/43809
http://www.securityfocus.com/archive/1/520102/100/0/threaded
http://www.redhat.com/support/errata/RHSA-2011-0162.html
http://www.redhat.com/support/errata/RHSA-2011-0007.html
http://www.redhat.com/support/errata/RHSA-2011-0004.html
http://www.redhat.com/support/errata/RHSA-2010-0958.html
http://www.openwall.com/lists/oss-security/2010/10/25/3
http://www.openwall.com/lists/oss-security/2010/10/07/1
http://www.openwall.com/lists/oss-security/2010/10/06/6
http://www.openwall.com/lists/oss-security/2010/09/25/2
http://www.mandriva.com/security/advisories?name=MDVSA-2011:051
http://www.debian.org/security/2010/dsa-2126
http://secunia.com/advisories/46397
http://secunia.com/advisories/43291
http://secunia.com/advisories/42963
http://secunia.com/advisories/42932
http://secunia.com/advisories/42890
http://secunia.com/advisories/42789
http://secunia.com/advisories/42778
http://lists.opensuse.org/opensuse-security-announce/2011-02/msg00002.html
http://lists.opensuse.org/opensuse-security-announce/2011-02/msg00000.html
http://lists.opensuse.org/opensuse-security-announce/2011-01/msg00004.html
http://lists.opensuse.org/opensuse-security-announce/2011-01/msg00000.html
http://lists.opensuse.org/opensuse-security-announce/2010-12/msg00004.html