The MITRE CVE dictionary describes this issue as:
The div_long_long_rem implementation in include/asm-x86/div64.h in the Linux kernel before 2.6.26 on the x86 platform allows local users to cause a denial of service (Divide Error Fault and panic) via a clock_gettime system call.
Find out more about CVE-2011-3209 from the
MITRE CVE dictionary dictionary and
This issue did not affect the Linux kernels as shipped with Red Hat Enterprise Linux 4, 6, and Red Hat Enterprise MRG, as they either do not have the sample_to_timespec() function, or have already backported upstream commit f8bd2258, which addresses this issue. It was addressed in Red Hat Enterprise Linux 5 via https://rhn.redhat.com/errata/RHSA-2011-1386.html.