Multiple integer overflows in the next_pidmap function in kernel/pid.c in the Linux kernel before 2.6.38.4 allow local users to cause a denial of service (system crash) via a crafted (1) getdents or (2) readdir system call.
https://exchange.xforce.ibmcloud.com/vulnerabilities/66876
https://bugzilla.redhat.com/show_bug.cgi?id=697822
http://www.ubuntu.com/usn/USN-1146-1
http://www.securityfocus.com/bid/47497
http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.38.4
http://securitytracker.com/id?1025420
http://secunia.com/advisories/44164
http://rhn.redhat.com/errata/RHSA-2011-0927.html
http://openwall.com/lists/oss-security/2011/04/20/1