[PATCH RFC 1/9] LSM: Add /sys/kernel/security/lsm
Tetsuo Handa
penguin-kernel at I-love.SAKURA.ne.jp
Fri Mar 17 12:52:09 UTC 2017
Casey Schaufler wrote:
> Subject: [PATCH RFC 1/9] LSM: Add /sys/kernel/security/lsm
>
> This has been accepted into security next - provided for completeness
Before going to "[PATCH RFC 5/9] LSM: General but not extreme module
stacking", what do you think about below change?
----------------------------------------
>From 8fe80e4b6a479a81d720571ad3b5979f6fd1e6ae Mon Sep 17 00:00:00 2001
From: Tetsuo Handa <penguin-kernel at I-love.SAKURA.ne.jp>
Date: Fri, 17 Mar 2017 21:34:51 +0900
Subject: [PATCH] LSM: Pass module name via "union security_list_options".
Commit d69dece5f5b6bc7a ("LSM: Add /sys/kernel/security/lsm") added
"char *lsm" field to "struct security_hook_list". But it is currently
never used after set at initialization time. While there is a plan that
this field will be used by "LSM: General but not extreme module stacking"
patch, there is no point with setting the same value to each element of
"struct security_hook_list" array. We can keep "struct security_hook_list"
4 * sizeof(void *) bytes if we keep this field in "union
security_list_options".
The "char *" argument in security_add_hooks() was removed because we can
fetch it from security_list_options"->module_name field. This implies
that setting security_list_options"->module_name field is mandatory.
Signed-off-by: Tetsuo Handa <penguin-kernel at I-love.SAKURA.ne.jp>
---
include/linux/lsm_hooks.h | 8 +++++---
security/apparmor/lsm.c | 4 ++--
security/commoncap.c | 4 ++--
security/loadpin/loadpin.c | 3 ++-
security/security.c | 13 +++++++------
security/selinux/hooks.c | 3 ++-
security/smack/smack_lsm.c | 3 ++-
security/tomoyo/tomoyo.c | 3 ++-
security/yama/yama_lsm.c | 3 ++-
9 files changed, 26 insertions(+), 18 deletions(-)
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index a4193c3..d10b4f7 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -29,6 +29,8 @@
#include <linux/rculist.h>
/**
+ * @module_name: the name of the security module
+ *
* Security hooks for program execution operations.
*
* @bprm_set_creds:
@@ -1340,6 +1342,7 @@
*/
union security_list_options {
+ const char *module_name;
int (*binder_set_context_mgr)(struct task_struct *mgr);
int (*binder_transaction)(struct task_struct *from,
struct task_struct *to);
@@ -1664,6 +1667,7 @@
};
struct security_hook_heads {
+ struct list_head module_name;
struct list_head binder_set_context_mgr;
struct list_head binder_transaction;
struct list_head binder_transfer_binder;
@@ -1886,7 +1890,6 @@ struct security_hook_list {
struct list_head list;
struct list_head *head;
union security_list_options hook;
- char *lsm;
};
/*
@@ -1901,8 +1904,7 @@ struct security_hook_list {
extern struct security_hook_heads security_hook_heads;
extern char *lsm_names;
-extern void security_add_hooks(struct security_hook_list *hooks, int count,
- char *lsm);
+extern void security_add_hooks(struct security_hook_list *hooks, int count);
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
/*
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index e287b69..dc21835 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -588,6 +588,7 @@ static int apparmor_task_setrlimit(struct task_struct *task,
}
static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
+ LSM_HOOK_INIT(module_name, "apparmor"),
LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
LSM_HOOK_INIT(capget, apparmor_capget),
@@ -996,8 +997,7 @@ static int __init apparmor_init(void)
aa_free_root_ns();
goto buffers_out;
}
- security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
- "apparmor");
+ security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks));
/* Report that AppArmor successfully initialized */
apparmor_initialized = 1;
diff --git a/security/commoncap.c b/security/commoncap.c
index 7abebd7..1ced4ee 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -1072,6 +1072,7 @@ int cap_mmap_file(struct file *file, unsigned long reqprot,
#ifdef CONFIG_SECURITY
struct security_hook_list capability_hooks[] __lsm_ro_after_init = {
+ LSM_HOOK_INIT(module_name, "capability"),
LSM_HOOK_INIT(capable, cap_capable),
LSM_HOOK_INIT(settime, cap_settime),
LSM_HOOK_INIT(ptrace_access_check, cap_ptrace_access_check),
@@ -1094,8 +1095,7 @@ struct security_hook_list capability_hooks[] __lsm_ro_after_init = {
void __init capability_add_hooks(void)
{
- security_add_hooks(capability_hooks, ARRAY_SIZE(capability_hooks),
- "capability");
+ security_add_hooks(capability_hooks, ARRAY_SIZE(capability_hooks));
}
#endif /* CONFIG_SECURITY */
diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c
index dbe6efd..c126c74 100644
--- a/security/loadpin/loadpin.c
+++ b/security/loadpin/loadpin.c
@@ -175,6 +175,7 @@ static int loadpin_read_file(struct file *file, enum kernel_read_file_id id)
}
static struct security_hook_list loadpin_hooks[] __lsm_ro_after_init = {
+ LSM_HOOK_INIT(module_name, "loadpin"),
LSM_HOOK_INIT(sb_free_security, loadpin_sb_free_security),
LSM_HOOK_INIT(kernel_read_file, loadpin_read_file),
};
@@ -182,7 +183,7 @@ static int loadpin_read_file(struct file *file, enum kernel_read_file_id id)
void __init loadpin_add_hooks(void)
{
pr_info("ready to pin (currently %sabled)", enabled ? "en" : "dis");
- security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks), "loadpin");
+ security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks));
}
/* Should not be mutable after boot, so not listed in sysfs (perm == 0). */
diff --git a/security/security.c b/security/security.c
index 5b6cdd0..ae57a84 100644
--- a/security/security.c
+++ b/security/security.c
@@ -79,7 +79,7 @@ static int __init choose_lsm(char *str)
}
__setup("security=", choose_lsm);
-static int lsm_append(char *new, char **result)
+static int lsm_append(const char *new, char **result)
{
char *cp;
@@ -118,20 +118,20 @@ int __init security_module_enable(const char *module)
* security_add_hooks - Add a modules hooks to the hook lists.
* @hooks: the hooks to add
* @count: the number of hooks to add
- * @lsm: the name of the security module
*
* Each LSM has to register its hooks with the infrastructure.
*/
-void __init security_add_hooks(struct security_hook_list *hooks, int count,
- char *lsm)
+void __init security_add_hooks(struct security_hook_list *hooks, int count)
{
int i;
+ const char *lsm = NULL;
for (i = 0; i < count; i++) {
- hooks[i].lsm = lsm;
list_add_tail_rcu(&hooks[i].list, hooks[i].head);
+ if (hooks[i].head == &security_hook_heads.module_name)
+ lsm = hooks[i].hook.module_name;
}
- if (lsm_append(lsm, &lsm_names) < 0)
+ if (!lsm || lsm_append(lsm, &lsm_names) < 0)
panic("%s - Cannot get early memory.\n", __func__);
}
@@ -1634,6 +1634,7 @@ int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule,
#endif /* CONFIG_AUDIT */
struct security_hook_heads security_hook_heads __lsm_ro_after_init = {
+ .module_name = LIST_HEAD_INIT(security_hook_heads.module_name),
.binder_set_context_mgr =
LIST_HEAD_INIT(security_hook_heads.binder_set_context_mgr),
.binder_transaction =
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index d37a723..cd7befe 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -6124,6 +6124,7 @@ static int selinux_key_getsecurity(struct key *key, char **_buffer)
#endif
static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
+ LSM_HOOK_INIT(module_name, "selinux"),
LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
@@ -6366,7 +6367,7 @@ static __init int selinux_init(void)
0, SLAB_PANIC, NULL);
avc_init();
- security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
+ security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
panic("SELinux: Unable to register AVC netcache callback\n");
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 927e60e..f2457b8 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -4634,6 +4634,7 @@ static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
}
static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
+ LSM_HOOK_INIT(module_name, "smack"),
LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
LSM_HOOK_INIT(syslog, smack_syslog),
@@ -4850,7 +4851,7 @@ static __init int smack_init(void)
/*
* Register with LSM
*/
- security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack");
+ security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks));
return 0;
}
diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c
index 0de150d..6ba6139 100644
--- a/security/tomoyo/tomoyo.c
+++ b/security/tomoyo/tomoyo.c
@@ -488,6 +488,7 @@ static int tomoyo_socket_sendmsg(struct socket *sock, struct msghdr *msg,
* registering TOMOYO.
*/
static struct security_hook_list tomoyo_hooks[] __lsm_ro_after_init = {
+ LSM_HOOK_INIT(module_name, "tomoyo"),
LSM_HOOK_INIT(task_alloc, tomoyo_task_alloc),
LSM_HOOK_INIT(task_free, tomoyo_task_free),
LSM_HOOK_INIT(bprm_set_creds, tomoyo_bprm_set_creds),
@@ -534,7 +535,7 @@ static int __init tomoyo_init(void)
if (!security_module_enable("tomoyo"))
return 0;
/* register ourselves with the security framework */
- security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks), "tomoyo");
+ security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks));
printk(KERN_INFO "TOMOYO Linux initialized\n");
current->security = &ts;
tomoyo_mm_init();
diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
index 8298e09..3290d33 100644
--- a/security/yama/yama_lsm.c
+++ b/security/yama/yama_lsm.c
@@ -429,6 +429,7 @@ int yama_ptrace_traceme(struct task_struct *parent)
}
static struct security_hook_list yama_hooks[] __lsm_ro_after_init = {
+ LSM_HOOK_INIT(module_name, "yama"),
LSM_HOOK_INIT(ptrace_access_check, yama_ptrace_access_check),
LSM_HOOK_INIT(ptrace_traceme, yama_ptrace_traceme),
LSM_HOOK_INIT(task_prctl, yama_task_prctl),
@@ -485,6 +486,6 @@ static inline void yama_init_sysctl(void) { }
void __init yama_add_hooks(void)
{
pr_info("Yama: becoming mindful.\n");
- security_add_hooks(yama_hooks, ARRAY_SIZE(yama_hooks), "yama");
+ security_add_hooks(yama_hooks, ARRAY_SIZE(yama_hooks));
yama_init_sysctl();
}
--
1.8.3.1
--
To unsubscribe from this list: send the line "unsubscribe linux-security-module" in
the body of a message to majordomo at vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
More information about the Linux-security-module-archive
mailing list