Re: [PATCH v7 06/15] crypto: hash: support hardware-only progressive hashing

Hi James,

On 2026-08-13T19:58:53, James Hilliard <[email protected]> wrote:
> crypto: hash: support hardware-only progressive hashing
>
> FIT configuration signatures hash multiple discontiguous regions through
> the legacy progressive hash interface. This still requires a software
> implementation even when image hashes use a driver-model hardware
> provider.
>
> Add provider selection for progressive driver-model hashing and use it
> from hash_calculate(). Allow SPL_SHA256_LEGACY to be disabled explicitly,
> link the SHA-256 software support only for a selected software backend,
> and make legacy fallback paths reject an algorithm whose software
> callbacks are absent.
>
> Extend the hash provider-selection test to cover progressive
> initialization.

That seems like a stale comment, at least for this commit.

>
> This permits SPL to retain SHA-256 FIT support while relying exclusively
> on a hardware hash provider.
>
> Signed-off-by: James Hilliard <[email protected]>
>
> boot/image-fit.c                  |  2 +-
>  common/hash.c                     | 21 +++++++++++++++++++--
>  drivers/crypto/hash/hash-uclass.c | 31 +++++++++++++++++++++++++++++++
>  include/u-boot/hash.h             | 14 ++++++++++++++
>  lib/Makefile                      |  4 ++--
>  lib/hash-checksum.c               | 28 +++++++++++++++++++++++++++-
>  lib/mbedtls/Kconfig               |  2 +-
>  7 files changed, 95 insertions(+), 7 deletions(-)

> diff --git a/lib/hash-checksum.c b/lib/hash-checksum.c
> @@ -20,13 +22,37 @@ int hash_calculate(const char *name,
> +             if (!ret) {
> +                     for (i = 0; i < region_count; i++) {
> +                             ret = hash_update(dev, ctx, region[i].data,
> +                                               region[i].size);
> +                             if (ret)
> +                                     return ret;
> +                     }
> +
> +                     return hash_finish(dev, ctx, checksum);
> +             }

If hash_update() fails partway through, the provider's ctx is leaked -
nothing calls hash_finish() or an equivalent free path. Do you need an
explicit teardown on the error exit?

Reviewed-by: Simon Glass <[email protected]>

Regards,
Simon