On 7/21/2025 4:21 PM, Paul Moore wrote:
> Rename the builtin_lsm_order variable to lsm_order_builtin,
> chosen_lsm_order to lsm_order_cmdline, chosen_major_lsm to
> lsm_order_legacy, ordered_lsms[] to lsm_order[], and exclusive
> to lsm_exclusive.
>
> This patch also renames the associated kernel command line parsing
> functions and adds some basic function comment blocks. The parsing
> function choose_major_lsm() was renamed to lsm_choose_security(),
> choose_lsm_order() to lsm_choose_lsm(), and enable_debug() to
> lsm_debug_enable().
>
> Reviewed-by: Kees Cook <k...@kernel.org>
> Reviewed-by: John Johansen <john.johan...@canonical.com>
> Signed-off-by: Paul Moore <p...@paul-moore.com>
Reviewed-by: Casey Schaufler <ca...@schaufler-ca.com>
> ---
> security/lsm_init.c | 86 +++++++++++++++++++++++++--------------------
> 1 file changed, 48 insertions(+), 38 deletions(-)
>
> diff --git a/security/lsm_init.c b/security/lsm_init.c
> index 96d51e4d625b..cbdfac31ede4 100644
> --- a/security/lsm_init.c
> +++ b/security/lsm_init.c
> @@ -16,14 +16,14 @@ char *lsm_names;
> extern struct lsm_info __start_lsm_info[], __end_lsm_info[];
> extern struct lsm_info __start_early_lsm_info[], __end_early_lsm_info[];
>
> -/* Boot-time LSM user choice */
> -static __initconst const char *const builtin_lsm_order = CONFIG_LSM;
> -static __initdata const char *chosen_lsm_order;
> -static __initdata const char *chosen_major_lsm;
> +/* Build and boot-time LSM ordering. */
> +static __initconst const char *const lsm_order_builtin = CONFIG_LSM;
> +static __initdata const char *lsm_order_cmdline;
> +static __initdata const char *lsm_order_legacy;
>
> /* Ordered list of LSMs to initialize. */
> -static __initdata struct lsm_info *ordered_lsms[MAX_LSM_COUNT + 1];
> -static __initdata struct lsm_info *exclusive;
> +static __initdata struct lsm_info *lsm_order[MAX_LSM_COUNT + 1];
> +static __initdata struct lsm_info *lsm_exclusive;
>
> static __initdata bool debug;
> #define init_debug(...)
> \
> @@ -33,7 +33,7 @@ static __initdata bool debug;
> } while (0)
>
> #define lsm_order_for_each(iter) \
> - for ((iter) = ordered_lsms; *(iter); (iter)++)
> + for ((iter) = lsm_order; *(iter); (iter)++)
> #define lsm_for_each_raw(iter)
> \
> for ((iter) = __start_lsm_info; \
> (iter) < __end_lsm_info; (iter)++)
> @@ -41,31 +41,41 @@ static __initdata bool debug;
> for ((iter) = __start_early_lsm_info; \
> (iter) < __end_early_lsm_info; (iter)++)
>
> -static int lsm_append(const char *new, char **result);
> -
> -/* Save user chosen LSM */
> -static int __init choose_major_lsm(char *str)
> +/**
> + * lsm_choose_security - Legacy "major" LSM selection
> + * @str: kernel command line parameter
> + */
> +static int __init lsm_choose_security(char *str)
> {
> - chosen_major_lsm = str;
> + lsm_order_legacy = str;
> return 1;
> }
> -__setup("security=", choose_major_lsm);
> +__setup("security=", lsm_choose_security);
>
> -/* Explicitly choose LSM initialization order. */
> -static int __init choose_lsm_order(char *str)
> +/**
> + * lsm_choose_lsm - Modern LSM selection
> + * @str: kernel command line parameter
> + */
> +static int __init lsm_choose_lsm(char *str)
> {
> - chosen_lsm_order = str;
> + lsm_order_cmdline = str;
> return 1;
> }
> -__setup("lsm=", choose_lsm_order);
> +__setup("lsm=", lsm_choose_lsm);
>
> -/* Enable LSM order debugging. */
> -static int __init enable_debug(char *str)
> +/**
> + * lsm_debug_enable - Enable LSM framework debugging
> + * @str: kernel command line parameter
> + *
> + * Currently we only provide debug info during LSM initialization, but we may
> + * want to expand this in the future.
> + */
> +static int __init lsm_debug_enable(char *str)
> {
> debug = true;
> return 1;
> }
> -__setup("lsm.debug", enable_debug);
> +__setup("lsm.debug", lsm_debug_enable);
>
> /* Mark an LSM's enabled flag. */
> static int lsm_enabled_true __initdata = 1;
> @@ -127,7 +137,7 @@ static void __init append_ordered_lsm(struct lsm_info
> *lsm, const char *from)
> /* Enable this LSM, if it is not already set. */
> if (!lsm->enabled)
> lsm->enabled = &lsm_enabled_true;
> - ordered_lsms[last_lsm] = lsm;
> + lsm_order[last_lsm] = lsm;
> lsm_idlist[last_lsm++] = lsm->id;
>
> init_debug("%s ordered: %s (%s)\n", from, lsm->id->name,
> @@ -157,7 +167,7 @@ static void __init lsm_prepare(struct lsm_info *lsm)
> if (!is_enabled(lsm)) {
> set_enabled(lsm, false);
> return;
> - } else if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) {
> + } else if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && lsm_exclusive) {
> init_debug("exclusive disabled: %s\n", lsm->id->name);
> set_enabled(lsm, false);
> return;
> @@ -165,9 +175,9 @@ static void __init lsm_prepare(struct lsm_info *lsm)
>
> /* Mark the LSM as enabled. */
> set_enabled(lsm, true);
> - if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) {
> + if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !lsm_exclusive) {
> init_debug("exclusive chosen: %s\n", lsm->id->name);
> - exclusive = lsm;
> + lsm_exclusive = lsm;
> }
>
> /* Register the LSM blob sizes. */
> @@ -223,7 +233,7 @@ static void __init ordered_lsm_parse(const char *order,
> const char *origin)
> }
>
> /* Process "security=", if given. */
> - if (chosen_major_lsm) {
> + if (lsm_order_legacy) {
> struct lsm_info *major;
>
> /*
> @@ -234,10 +244,10 @@ static void __init ordered_lsm_parse(const char *order,
> const char *origin)
> */
> lsm_for_each_raw(major) {
> if ((major->flags & LSM_FLAG_LEGACY_MAJOR) &&
> - strcmp(major->id->name, chosen_major_lsm) != 0) {
> + strcmp(major->id->name, lsm_order_legacy) != 0) {
> set_enabled(major, false);
> init_debug("security=%s disabled: %s (only one
> legacy major LSM)\n",
> - chosen_major_lsm, major->id->name);
> + lsm_order_legacy, major->id->name);
> }
> }
> }
> @@ -262,11 +272,11 @@ static void __init ordered_lsm_parse(const char *order,
> const char *origin)
> }
>
> /* Process "security=", if given. */
> - if (chosen_major_lsm) {
> + if (lsm_order_legacy) {
> lsm_for_each_raw(lsm) {
> if (exists_ordered_lsm(lsm))
> continue;
> - if (strcmp(lsm->id->name, chosen_major_lsm) == 0)
> + if (strcmp(lsm->id->name, lsm_order_legacy) == 0)
> append_ordered_lsm(lsm, "security=");
> }
> }
> @@ -298,15 +308,15 @@ static void __init lsm_init_ordered(void)
> struct lsm_info **lsm;
> struct lsm_info *early;
>
> - if (chosen_lsm_order) {
> - if (chosen_major_lsm) {
> + if (lsm_order_cmdline) {
> + if (lsm_order_legacy) {
> pr_warn("security=%s is ignored because it is
> superseded by lsm=%s\n",
> - chosen_major_lsm, chosen_lsm_order);
> - chosen_major_lsm = NULL;
> + lsm_order_legacy, lsm_order_cmdline);
> + lsm_order_legacy = NULL;
> }
> - ordered_lsm_parse(chosen_lsm_order, "cmdline");
> + ordered_lsm_parse(lsm_order_cmdline, "cmdline");
> } else
> - ordered_lsm_parse(builtin_lsm_order, "builtin");
> + ordered_lsm_parse(lsm_order_builtin, "builtin");
>
> lsm_order_for_each(lsm) {
> lsm_prepare(*lsm);
> @@ -467,9 +477,9 @@ int __init security_init(void)
> {
> struct lsm_info *lsm;
>
> - init_debug("legacy security=%s\n", chosen_major_lsm ? : "
> *unspecified*");
> - init_debug(" CONFIG_LSM=%s\n", builtin_lsm_order);
> - init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*");
> + init_debug("legacy security=%s\n", lsm_order_legacy ? : "
> *unspecified*");
> + init_debug(" CONFIG_LSM=%s\n", lsm_order_builtin);
> + init_debug("boot arg lsm=%s\n", lsm_order_cmdline ? : " *unspecified*");
>
> /*
> * Append the names of the early LSM modules now that kmalloc() is
