Re: [PATCH] crypto: ecc - Fix off-by-one missing to clear most significant digit

From: Herbert Xu
Date: Sun Jun 16 2024 - 02:07:01 EST


On Thu, Jun 13, 2024 at 05:38:20PM -0400, Stefan Berger wrote:
> Fix an off-by-one error where the most significant digit was not
> initialized leading to signature verification failures by the testmgr.
>
> Example: If a curve requires ndigits (=9) and diff (=2) indicates that
> 2 digits need to be set to zero then start with digit 'ndigits - diff' (=7)
> and clear 'diff' digits starting from there, so 7 and 8.
>
> Reported-by: Venkat Rao Bagalkote <venkat88@xxxxxxxxxxxxxxxxxx>
> Closes: https://lore.kernel.org/linux-crypto/619bc2de-b18a-4939-a652-9ca886bf6349@xxxxxxxxxxxxx/T/#m045d8812409ce233c17fcdb8b88b6629c671f9f4
> Fixes: 2fd2a82ccbfc ("crypto: ecdsa - Use ecc_digits_from_bytes to create hash digits array")
> Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
> ---
> crypto/ecc.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

Patch applied. Thanks.
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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