Re: [PATCH v2] kvm: nVMX: off by one in vmx_write_pml_buffer()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On 11/05/2017 09:42, Dan Carpenter wrote:
> On Thu, May 11, 2017 at 09:31:17AM +0200, Paolo Bonzini wrote:
>>
>>
>> On 10/05/2017 22:43, Dan Carpenter wrote:
>>> There are PML_ENTITY_NUM elements in the pml_address[] array so the >
>>> should be >= or we write beyond the end of the array when we do:
>>>
>>> 	pml_address[vmcs12->guest_pml_index--] = gpa;
>>>
>>> This causes a static checker warning but the runtime impact is minimal.
>>> The ->guest_pml_index variable can only be set to PML_ENTITY_NUM by a
>>> buggy hypervisor.
>>
>> The v1 commit message is better actually.  You can always replace
>> "buggy" with "malicious".
> 
> Can't the hypervisor already basically do what it wants?

Here you have a nested hypervisor, that can force the host hypervisor to
do a kmap and write at offset 4096 inside (well, actually outside...)
that kmap.

Paolo
--
To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Kernel Development]     [Kernel Announce]     [Kernel Newbies]     [Linux Networking Development]     [Share Photos]     [IDE]     [Security]     [Git]     [Netfilter]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Device Mapper]

  Powered by Linux