[PATCH 3/3] integrity/platform_certs: Allow loading of keys in static key management mode

[Andrew Donnellan]

On Wed, 2025-04-30 at 14:33 +0530, Srish Srinivasan wrote:
> On PLPKS enabled PowerVM LPAR, there is no provision to load signed
> third-party kernel modules when the key management mode is static.
> This
> is because keys from secure boot secvars are only loaded when the key
> management mode is dynamic.
> 
> Allow loading of the trustedcadb and moduledb keys even in the static
> key management mode, where the secvar format string takes the form
> "ibm,plpks-sb-v0".
> 
> Signed-off-by: Srish Srinivasan <ssrish at linux.ibm.com>
> Reviewed-by: Mimi Zohar <zohar at linux.ibm.com>
> Reviewed-by: Stefan Berger <stefanb at linux.ibm.com>

Reviewed-by: Andrew Donnellan <ajd at linux.ibm.com>

> ---
>  security/integrity/platform_certs/load_powerpc.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/security/integrity/platform_certs/load_powerpc.c
> b/security/integrity/platform_certs/load_powerpc.c
> index c85febca3343..714c961a00f5 100644
> --- a/security/integrity/platform_certs/load_powerpc.c
> +++ b/security/integrity/platform_certs/load_powerpc.c
> @@ -75,12 +75,13 @@ static int __init load_powerpc_certs(void)
>  		return -ENODEV;
>  
>  	// Check for known secure boot implementations from OPAL or
> PLPKS
> -	if (strcmp("ibm,edk2-compat-v1", buf) && strcmp("ibm,plpks-
> sb-v1", buf)) {
> +	if (strcmp("ibm,edk2-compat-v1", buf) && strcmp("ibm,plpks-
> sb-v1", buf) &&
> +	    strcmp("ibm,plpks-sb-v0", buf)) {
>  		pr_err("Unsupported secvar implementation \"%s\",
> not loading certs\n", buf);
>  		return -ENODEV;
>  	}
>  
> -	if (strcmp("ibm,plpks-sb-v1", buf) == 0)
> +	if (strcmp("ibm,plpks-sb-v1", buf) == 0 ||
> strcmp("ibm,plpks-sb-v0", buf) == 0)
>  		/* PLPKS authenticated variables ESL data is
> prefixed with 8 bytes of timestamp */
>  		offset = 8;
>  

-- 
Andrew Donnellan    OzLabs, ADL Canberra
ajd at linux.ibm.com   IBM Australia Limited