[PATCH v5 16/38] LoadPin: Initialize as ordered LSM

From: Casey Schaufler
Date: Tue Dec 11 2018 - 17:46:47 EST


From: Kees Cook <keescook@xxxxxxxxxxxx>

This converts LoadPin from being a direct "minor" LSM into an ordered LSM.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Reviewed-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
---
include/linux/lsm_hooks.h | 5 -----
security/Kconfig | 39 +--------------------------------------
security/loadpin/loadpin.c | 8 +++++++-
security/security.c | 1 -
4 files changed, 8 insertions(+), 45 deletions(-)

diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 7d04a0c32011..b565c0c10269 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -2092,10 +2092,5 @@ extern void __init yama_add_hooks(void);
#else
static inline void __init yama_add_hooks(void) { }
#endif
-#ifdef CONFIG_SECURITY_LOADPIN
-void __init loadpin_add_hooks(void);
-#else
-static inline void loadpin_add_hooks(void) { };
-#endif

#endif /* ! __LINUX_LSM_HOOKS_H */
diff --git a/security/Kconfig b/security/Kconfig
index 41aa0be6142f..566d54215cbe 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -239,46 +239,9 @@ source security/yama/Kconfig

source security/integrity/Kconfig

-choice
- prompt "Default security module"
- default DEFAULT_SECURITY_SELINUX if SECURITY_SELINUX
- default DEFAULT_SECURITY_SMACK if SECURITY_SMACK
- default DEFAULT_SECURITY_TOMOYO if SECURITY_TOMOYO
- default DEFAULT_SECURITY_APPARMOR if SECURITY_APPARMOR
- default DEFAULT_SECURITY_DAC
-
- help
- Select the security module that will be used by default if the
- kernel parameter security= is not specified.
-
- config DEFAULT_SECURITY_SELINUX
- bool "SELinux" if SECURITY_SELINUX=y
-
- config DEFAULT_SECURITY_SMACK
- bool "Simplified Mandatory Access Control" if SECURITY_SMACK=y
-
- config DEFAULT_SECURITY_TOMOYO
- bool "TOMOYO" if SECURITY_TOMOYO=y
-
- config DEFAULT_SECURITY_APPARMOR
- bool "AppArmor" if SECURITY_APPARMOR=y
-
- config DEFAULT_SECURITY_DAC
- bool "Unix Discretionary Access Controls"
-
-endchoice
-
-config DEFAULT_SECURITY
- string
- default "selinux" if DEFAULT_SECURITY_SELINUX
- default "smack" if DEFAULT_SECURITY_SMACK
- default "tomoyo" if DEFAULT_SECURITY_TOMOYO
- default "apparmor" if DEFAULT_SECURITY_APPARMOR
- default "" if DEFAULT_SECURITY_DAC
-
config LSM
string "Ordered list of enabled LSMs"
- default "integrity"
+ default "loadpin,integrity,selinux,smack,tomoyo,apparmor"
help
A comma-separated list of LSMs, in initialization order.
Any LSMs left off this list will be ignored. This can be
diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c
index 48f39631b370..055fb0a64169 100644
--- a/security/loadpin/loadpin.c
+++ b/security/loadpin/loadpin.c
@@ -187,13 +187,19 @@ static struct security_hook_list loadpin_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(kernel_load_data, loadpin_load_data),
};

-void __init loadpin_add_hooks(void)
+static int __init loadpin_init(void)
{
pr_info("ready to pin (currently %senforcing)\n",
enforce ? "" : "not ");
security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks), "loadpin");
+ return 0;
}

+DEFINE_LSM(loadpin) = {
+ .name = "loadpin",
+ .init = loadpin_init,
+};
+
/* Should not be mutable after boot, so not listed in sysfs (perm == 0). */
module_param(enforce, int, 0);
MODULE_PARM_DESC(enforce, "Enforce module/firmware pinning");
diff --git a/security/security.c b/security/security.c
index 3fac0ff39944..0c092d62cc47 100644
--- a/security/security.c
+++ b/security/security.c
@@ -275,7 +275,6 @@ int __init security_init(void)
*/
capability_add_hooks();
yama_add_hooks();
- loadpin_add_hooks();

/* Load LSMs in specified order. */
ordered_lsm_init();
--
2.14.5