[PATCH v5 03/38] LSM: Plumb visibility into optional "enabled" state

[Casey Schaufler]

From: Kees Cook <keescook at chromium.org>

In preparation for lifting the "is this LSM enabled?" logic out of the
individual LSMs, pass in any special enabled state tracking (as needed
for SELinux, AppArmor, and LoadPin). This should be an "int" to include
handling any future cases where "enabled" is exposed via sysctl which
has no "bool" type.

Signed-off-by: Kees Cook <keescook at chromium.org>
Reviewed-by: Casey Schaufler <casey at schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen at canonical.com>
---
 include/linux/lsm_hooks.h | 1 +
 security/apparmor/lsm.c   | 5 +++--
 security/selinux/hooks.c  | 1 +
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 63c0e102de20..4e2e9cdf78c6 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -2044,6 +2044,7 @@ extern void security_add_hooks(struct security_hook_list *hooks, int count,
 struct lsm_info {
 	const char *name;	/* Required. */
 	unsigned long flags;	/* Optional: flags describing LSM */
+	int *enabled;		/* Optional: NULL means enabled. */
 	int (*init)(void);	/* Required. */
 };
 
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index 2edd35ca5044..127a540ef63a 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -1332,8 +1332,8 @@ bool aa_g_paranoid_load = true;
 module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
 
 /* Boot time disable flag */
-static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
-module_param_named(enabled, apparmor_enabled, bool, S_IRUGO);
+static int apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
+module_param_named(enabled, apparmor_enabled, int, 0444);
 
 static int __init apparmor_enabled_setup(char *str)
 {
@@ -1729,5 +1729,6 @@ static int __init apparmor_init(void)
 DEFINE_LSM(apparmor) = {
 	.name = "apparmor",
 	.flags = LSM_FLAG_LEGACY_MAJOR,
+	.enabled = &apparmor_enabled,
 	.init = apparmor_init,
 };
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 56c6f1849c80..efc0ac1b5019 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -7210,6 +7210,7 @@ void selinux_complete_init(void)
 DEFINE_LSM(selinux) = {
 	.name = "selinux",
 	.flags = LSM_FLAG_LEGACY_MAJOR,
+	.enabled = &selinux_enabled,
 	.init = selinux_init,
 };
 
-- 
2.14.5