The kvm_arch_vcpu_ioctl_set_sregs function in the KVM in Linux kernel 2.6 before 2.6.30, when running on x86 systems, does not validate the page table root in a KVM_SET_SREGS call, which allows local users to cause a denial of service (crash or hang) via a crafted cr3 value, which triggers a NULL pointer dereference in the gfn_to_rmap function.

References

• https://nvd.nist.gov/vuln/detail/CVE-2009-2287
• http://git.kernel.org/?p=linux/kernel/git/stable/stable-queue.git;a=blob;f=queue-2.6.30/kvm-x86-check-for-cr3-validity-in-ioctl_set_sregs.patch;h=b48a47dad2cf76358b327368f80c0805e6370c68;hb=e7c45b24f298b5d9efd7d401150f64a1b51aaac4
• http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=59839dfff5eabca01cc4e20b45797a60a80af8cb
• http://secunia.com/advisories/35675
• http://secunia.com/advisories/36045
• http://secunia.com/advisories/36054
• http://sourceforge.net/tracker/?func=detail&atid=893831&aid=2687641&group_id=180599
• http://www.debian.org/security/2009/dsa-1845
• http://www.mandriva.com/security/advisories?name=MDVSA-2010:198
• http://www.openwall.com/lists/oss-security/2009/06/30/1
• http://www.ubuntu.com/usn/usn-807-1