[PATCH security-next v3 12/29] LSM: Provide separate ordered initialization

[John Johansen]

On 09/24/2018 05:18 PM, Kees Cook wrote:
> This provides a place for ordered LSMs to be initialized, separate from
> the "major" LSMs. This is mainly a copy/paste from major_lsm_init() to
> ordered_lsm_init(), but it will change drastically in later patches.
> 
> What is not obvious in the patch is that this change moves the integrity
> LSM from major_lsm_init() into ordered_lsm_init(), since it is not marked
> with the LSM_FLAG_LEGACY_MAJOR. As it is the only LSM in the "ordered"
> list, there is no reordering yet created.
> 
> Signed-off-by: Kees Cook <keescook at chromium.org>

I know its already being done, but I don't like splitting the init
order

Reviewed-by: John Johansen <john.johansen at canonical.com>

> ---
>  security/security.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/security/security.c b/security/security.c
> index 1f055936a746..a886a978214a 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -52,12 +52,30 @@ static bool debug __initdata;
>  			pr_info(__VA_ARGS__);			\
>  	} while (0)
>  
> +static void __init ordered_lsm_init(void)
> +{
> +	struct lsm_info *lsm;
> +	int ret;
> +
> +	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
> +		if ((lsm->flags & LSM_FLAG_LEGACY_MAJOR) != 0)
> +			continue;
> +
> +		init_debug("initializing %s\n", lsm->name);
> +		ret = lsm->init();
> +		WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret);
> +	}
> +}
> +
>  static void __init major_lsm_init(void)
>  {
>  	struct lsm_info *lsm;
>  	int ret;
>  
>  	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
> +		if ((lsm->flags & LSM_FLAG_LEGACY_MAJOR) == 0)
> +			continue;
> +
>  		init_debug("initializing %s\n", lsm->name);
>  		ret = lsm->init();
>  		WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret);
> @@ -87,6 +105,9 @@ int __init security_init(void)
>  	yama_add_hooks();
>  	loadpin_add_hooks();
>  
> +	/* Load LSMs in specified order. */
> +	ordered_lsm_init();
> +
>  	/*
>  	 * Load all the remaining security modules.
>  	 */
>