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.
Weakness
The product dereferences a pointer that it expects to be valid but is NULL.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Linux_kernel | Linux | 2.6.0 (including) | 2.6.30 (excluding) |
| Kvm | Ubuntu | hardy | * |
| Kvm | Ubuntu | intrepid | * |
| Kvm | Ubuntu | jaunty | * |
| Kvm | Ubuntu | upstream | * |
| Linux | Ubuntu | hardy | * |
| Linux | Ubuntu | intrepid | * |
| Linux | Ubuntu | jaunty | * |
| Linux | Ubuntu | upstream | * |
| Linux-ec2 | Ubuntu | maverick | * |
| Linux-ec2 | Ubuntu | upstream | * |
| Linux-fsl-imx51 | Ubuntu | upstream | * |
| Linux-lts-backport-maverick | Ubuntu | upstream | * |
| Linux-mvl-dove | Ubuntu | karmic | * |
| Linux-mvl-dove | Ubuntu | upstream | * |
| Linux-source-2.6.15 | Ubuntu | dapper | * |
| Linux-source-2.6.15 | Ubuntu | upstream | * |
| Linux-ti-omap4 | Ubuntu | upstream | * |
Potential Mitigations
References
- http://git.kernel.org/?p=linux/kernel/git/stable/stable-queue.git%3Ba=blob%3Bf=queue-2.6.30/kvm-x86-check-for-cr3-validity-in-ioctl_set_sregs.patch%3Bh=b48a47dad2cf76358b327368f80c0805e6370c68%3Bhb=e7c45b24f298b5d9efd7d401150f64a1b51aaac4
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commitdiff%3Bh=59839dfff5eabca01cc4e20b45797a60a80af8cb
- http://secunia.com/advisories/35675
- http://secunia.com/advisories/36045
- http://secunia.com/advisories/36054
- http://sourceforge.net/tracker/?func=detail\u0026atid=893831\u0026aid=2687641\u0026group_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
- http://git.kernel.org/?p=linux/kernel/git/stable/stable-queue.git%3Ba=blob%3Bf=queue-2.6.30/kvm-x86-check-for-cr3-validity-in-ioctl_set_sregs.patch%3Bh=b48a47dad2cf76358b327368f80c0805e6370c68%3Bhb=e7c45b24f298b5d9efd7d401150f64a1b51aaac4
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commitdiff%3Bh=59839dfff5eabca01cc4e20b45797a60a80af8cb
- http://secunia.com/advisories/35675
- http://secunia.com/advisories/36045
- http://secunia.com/advisories/36054
- http://sourceforge.net/tracker/?func=detail\u0026atid=893831\u0026aid=2687641\u0026group_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