CVE-2009-4271 kernel: 32bit process on 64bit system DoS

[Eugene Teo <eugeneteo () kernel sg>]

STMicroelectronics reported a flaw in the Linux kernel, versions 2.6.9 
to 2.6.17, when running on x86_64, where a user could use a regular 
32bit process to trigger a kernel panic, without any special privileges. 
 The bug occurs when a 32bit user process triggers a segfault (i.e. 
de-reference a null-pointer) after having performed a mprotect() to 
restrict any rwx access on its VDSO page.

This only affects Red Hat Enterprise Linux 4.

https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2009-4271

Thanks, Eugene