[PATCH v3] KEYS: trusted: Fix trusted key backends when building as module

[Sumit Garg]

On Fri, 30 Jul 2021 at 06:58, Andreas Rammhold <andreas at rammhold.de> wrote:
>
> Before this commit the kernel could end up with no trusted key sources
> even though both of the currently supported backends (TPM and TEE) were
> compiled as modules. This manifested in the trusted key type not being
> registered at all.
>
> When checking if a CONFIG_… preprocessor variable is defined we only
> test for the builtin (=y) case and not the module (=m) case. By using
> the IS_REACHABLE() macro we do test for both cases.
>
> Fixes: 5d0682be3189 ("KEYS: trusted: Add generic trusted keys framework")
> Signed-off-by: Andreas Rammhold <andreas at rammhold.de>
> Reviewed-by: Jarkko Sakkinen <jarkko at kernel.org>
>
> ---
>
> v3:
> * Fixed patch formatting
>
> v2:
> * Fixed commit message
> * Switched from IS_DEFINED() to IS_REACHABLE()
>
>  security/keys/trusted-keys/trusted_core.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>

LGTM.

Reviewed-by: Sumit Garg <sumit.garg at linaro.org>

-Sumit

> diff --git a/security/keys/trusted-keys/trusted_core.c b/security/keys/trusted-keys/trusted_core.c
> index d5c891d8d353..5b35f1b87644 100644
> --- a/security/keys/trusted-keys/trusted_core.c
> +++ b/security/keys/trusted-keys/trusted_core.c
> @@ -27,10 +27,10 @@ module_param_named(source, trusted_key_source, charp, 0);
>  MODULE_PARM_DESC(source, "Select trusted keys source (tpm or tee)");
>
>  static const struct trusted_key_source trusted_key_sources[] = {
> -#if defined(CONFIG_TCG_TPM)
> +#if IS_REACHABLE(CONFIG_TCG_TPM)
>         { "tpm", &trusted_key_tpm_ops },
>  #endif
> -#if defined(CONFIG_TEE)
> +#if IS_REACHABLE(CONFIG_TEE)
>         { "tee", &trusted_key_tee_ops },
>  #endif
>  };
> --
> 2.32.0
>