[PATCH v2 0/2] nvme: fixup HKDF-Expand-Label implementation

[Hannes Reinecke]

On 8/22/25 03:09, Eric Biggers wrote:
> On Thu, Aug 21, 2025 at 01:48:14PM -0700, Chris Leech wrote:
>> As per RFC 8446 (TLS 1.3) the HKDF-Expand-Label function is using vectors
>> for the 'label' and 'context' field, but defines these vectors as a string
>> prefixed with the string length (in binary). The implementation in nvme
>> is missing the length prefix which was causing interoperability issues
>> with spec-conformant implementations.
>>
>> This patchset adds a function 'hkdf_expand_label()' to correctly implement
>> the HKDF-Expand-Label functionality and modifies the nvme driver to utilize
>> this function instead of the open-coded implementation.
>>
>> As usual, comments and reviews are welcome.
> 
> Well, it's nice that my review comment from last year is finally being
> addressed: https://lore.kernel.org/r/20240723014715.GB2319848@google.com
> 
Yeah, because I misread your comments, and was only focussed on the
'length' field (which is a 16-bit field at the start), and not on the
length fields of the individual vectors.

Reading specs is hard...

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
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