Re: [PATCH v12 12/26] ima: Only accept AUDIT rules for non-init_ima_ns namespaces for now

[Serge E. Hallyn]

On Wed, Apr 20, 2022 at 10:06:19AM -0400, Stefan Berger wrote:
> Only accept AUDIT rules for non-init_ima_ns namespaces for now. Reject

This sentence gives me trouble - i keep thinking you mean that you'll
reject AUDIT rules for init_ima_ns :)  Can you rephrase it as something
like

For non-init_ima_ns namespaces, only accept AUDIT rules for now.

:)

> all rules that require support for measuring, appraisal, and hashing.
> 
> Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
> Acked-by: Christian Brauner <brauner@xxxxxxxxxx>
> Reviewed-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
> 
> ---
> v9:
>   - Jump to err_audit when unsupported rules are detected
> ---
>  security/integrity/ima/ima_policy.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
> index 59e4ae5a6361..45a997709200 100644
> --- a/security/integrity/ima/ima_policy.c
> +++ b/security/integrity/ima/ima_policy.c
> @@ -1812,6 +1812,17 @@ static int ima_parse_rule(struct ima_namespace *ns,
>  			result = -EINVAL;
>  			break;
>  		}
> +
> +		/* IMA namespace only accepts AUDIT rules */
> +		if (ns != &init_ima_ns && result == 0) {
> +			switch (entry->action) {
> +			case MEASURE:
> +			case APPRAISE:
> +			case HASH:

So... what about DONT_MEASURE and DONT_APPRAISE?

> +				result = -EINVAL;
> +				goto err_audit;
> +			}
> +		}
>  	}
>  	if (!result && !ima_validate_rule(entry))
>  		result = -EINVAL;
> @@ -1824,6 +1835,7 @@ static int ima_parse_rule(struct ima_namespace *ns,
>  		check_template_modsig(template_desc);
>  	}
>  
> +err_audit:
>  	audit_log_format(ab, "res=%d", !result);
>  	audit_log_end(ab);
>  	return result;
> -- 
> 2.34.1