Re: [PATCH v7 3/6] x86/kexec: Carry forward IMA measurement log on kexec

Stefan Berger
2022-08-12T17:14:56Z

On 8/12/22 13:10, Borislav Petkov wrote:
> On Fri, Aug 12, 2022 at 12:43:02PM -0400, Stefan Berger wrote:
>> From: Jonathan McDowell <noodles@fb.com>
>>
>> On kexec file load, the Integrity Measurement Architecture (IMA)
>> subsystem may verify the IMA signature of the kernel and initramfs, and
>> measure it. The command line parameters passed to the kernel in the
>> kexec call may also be measured by IMA.
>>
>> A remote attestation service can verify a TPM quote based on the TPM
>> event log, the IMA measurement list and the TPM PCR data. This can
>> be achieved only if the IMA measurement log is carried over from the
>> current kernel to the next kernel across the kexec call.
>>
>> PowerPC and ARM64 both achieve this using device tree with a
>> "linux,ima-kexec-buffer" node. x86 platforms generally don't make use of
>> device tree, so use the setup_data mechanism to pass the IMA buffer to
>> the new kernel.
>>
>> Signed-off-by: Jonathan McDowell <noodles@fb.com>
>> Signed-off-by: Borislav Petkov <bp@suse.de>
>> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> # IMA function definitions
>> Link: https://lore.kernel.org/r/YmKyvlF3my1yWTvK@noodles-fedora-PC23Y6EG
>
> Is there any particular reason to keep sending a patch which is already
> upstream?
>

Yes, so this series can be tested by krobot. I only based this series on
5.19 so far, so if it's upstreamed since then it will go missing next
time when I base it on 5.20-rc1 or so.