LSM: Convert from initcall to struct lsm_info

In preparation for doing more interesting LSM init probing, this converts
the existing initcall system into an explicit call into a function pointer
from a section-collected struct lsm_info array.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: James Morris <james.morris@microsoft.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.morris@microsoft.com>

diff --git a/include/linux/init.h b/include/linux/init.h
index 77636539e77cef50e315179fed3ab4927715e221..9c2aba1dbabfc2064ab258d78e659a431e01416b 100644 (file)
--- a/include/linux/init.h
+++ b/include/linux/init.h
@@ -133,7 +133,6 @@ static inline initcall_t initcall_from_entry(initcall_entry_t *entry)
 #endif
 
 extern initcall_entry_t __con_initcall_start[], __con_initcall_end[];
-extern initcall_entry_t __start_lsm_info[], __end_lsm_info[];
 
 /* Used for contructor calls. */
 typedef void (*ctor_fn_t)(void);
@@ -236,7 +235,6 @@ extern bool initcall_debug;
        static exitcall_t __exitcall_##fn __exit_call = fn
 
 #define console_initcall(fn)   ___define_initcall(fn,, .con_initcall)
-#define security_initcall(fn)  ___define_initcall(fn,, .lsm_info)
 
 struct obs_kernel_param {
        const char *str;

diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 97a020c616ad1f693507e256cece8ef1ab81d87d..d13059feca0939f04792169a787afbf920a0efec 100644 (file)
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -2039,6 +2039,18 @@ extern char *lsm_names;
 extern void security_add_hooks(struct security_hook_list *hooks, int count,
                                char *lsm);
 
+struct lsm_info {
+       int (*init)(void);      /* Required. */
+};
+
+extern struct lsm_info __start_lsm_info[], __end_lsm_info[];
+
+#define security_initcall(lsm)                                         \
+       static struct lsm_info __lsm_##lsm                              \
+               __used __section(.lsm_info.init)                        \
+               __aligned(sizeof(unsigned long))                        \
+               = { .init = lsm, }
+
 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
 /*
  * Assuring the safety of deleting a security module is up to

diff --git a/include/linux/module.h b/include/linux/module.h
index f807f15bebbe732b466d45d8d603991b4a1aa3ef..26497928375645a1bb203eec80494b402c6a03e6 100644 (file)
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -123,7 +123,6 @@ extern void cleanup_module(void);
 #define late_initcall_sync(fn)         module_init(fn)
 
 #define console_initcall(fn)           module_init(fn)
-#define security_initcall(fn)          module_init(fn)
 
 /* Each module must use one module_init(). */
 #define module_init(initfn)                                    \

diff --git a/security/integrity/iint.c b/security/integrity/iint.c
index 5a6810041e5c0aa957da3519c6bc227987f24a16..70d21b566955445cb28ce85632bd630650dd22d9 100644 (file)
--- a/security/integrity/iint.c
+++ b/security/integrity/iint.c
@@ -22,6 +22,7 @@
 #include <linux/file.h>
 #include <linux/uaccess.h>
 #include <linux/security.h>
+#include <linux/lsm_hooks.h>
 #include "integrity.h"
 
 static struct rb_root integrity_iint_tree = RB_ROOT;

diff --git a/security/security.c b/security/security.c
index 41a5da2c7fafc03a5fbf9d9a021f6c90d12b8955..e74f46fba5914cb089bf8abdaa4b53fecd455816 100644 (file)
--- a/security/security.c
+++ b/security/security.c
@@ -43,16 +43,12 @@ char *lsm_names;
 static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1] =
        CONFIG_DEFAULT_SECURITY;
 
-static void __init do_security_initcalls(void)
+static void __init major_lsm_init(void)
 {
-       initcall_t call;
-       initcall_entry_t *ce;
+       struct lsm_info *lsm;
 
-       ce = __start_lsm_info;
-       while (ce < __end_lsm_info) {
-               call = initcall_from_entry(ce);
-               call();
-               ce++;
+       for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
+               lsm->init();
        }
 }
 
@@ -82,7 +78,7 @@ int __init security_init(void)
        /*
         * Load all the remaining security modules.
         */
-       do_security_initcalls();
+       major_lsm_init();
 
        return 0;
 }