Re: [PATCH v8 05/19] ima: Move measurement list related variables into ima_namespace

[Mimi Zohar]

Hi Stefan,

On Tue, 2022-01-04 at 12:04 -0500, Stefan Berger wrote:
> From: Stefan Berger <stefanb@xxxxxxxxxxxxx>
> 
> Move measurement list related variables into the ima_namespace. This way a
> front-end like SecurityFS can show the measurement list inside an IMA
> namespace.
> 
> Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
> ---
>  security/integrity/ima/ima.h             |  5 +++--
>  security/integrity/ima/ima_fs.c          |  6 ++++--
>  security/integrity/ima/ima_init_ima_ns.c |  5 +++++
>  security/integrity/ima/ima_kexec.c       | 12 +++++++-----
>  security/integrity/ima/ima_queue.c       | 24 ++++++++++--------------
>  5 files changed, 29 insertions(+), 23 deletions(-)
> 
> diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
> index 68d8a8e6fd1d..ee16ce5050c8 100644
> --- a/security/integrity/ima/ima.h
> +++ b/security/integrity/ima/ima.h
> @@ -106,7 +106,6 @@ struct ima_queue_entry {
>  	struct list_head later;		/* place in ima_measurements list */
>  	struct ima_template_entry *entry;
>  };
> -extern struct list_head ima_measurements;	/* list of all measurements */
>  
>  /* Some details preceding the binary serialized measurement list */
>  struct ima_kexec_hdr {
> @@ -134,6 +133,8 @@ struct ima_namespace {
>  	int ima_policy_flag;
>  
>  	struct ima_h_table ima_htable;
> +	struct list_head ima_measurements;
> +	unsigned long binary_runtime_size;

Please add a comment indicating binary_runtime_size is only applicable
to ns_ima_init.


>  } __randomize_layout;
>  extern struct ima_namespace init_ima_ns;


> @@ -124,12 +119,13 @@ static int ima_add_digest_entry(struct ima_namespace *ns,
>   * entire binary_runtime_measurement list, including the ima_kexec_hdr
>   * structure.
>   */
> -unsigned long ima_get_binary_runtime_size(void)
> +unsigned long ima_get_binary_runtime_size(struct ima_namespace *ns)
>  {
> -	if (binary_runtime_size >= (ULONG_MAX - sizeof(struct ima_kexec_hdr)))
> +	if (ns->binary_runtime_size >=
> +				(ULONG_MAX - sizeof(struct ima_kexec_hdr)))
>  		return ULONG_MAX;
>  	else
> -		return binary_runtime_size + sizeof(struct ima_kexec_hdr);
> +		return ns->binary_runtime_size + sizeof(struct ima_kexec_hdr);
>  }
>  

Please update the function description indicating that either carrying
the measurement list across kexec is limited to ns_ima_init or not
supported by namespaces.

thanks,

Mimi