Merge tag 'selinux-pr-20230420' of git://git.kernel.org/pub/scm/linux…

…/kernel/git/pcmoore/selinux

Pull selinux updates from Paul Moore:

 - Stop passing the 'selinux_state' pointers as function arguments

   As discussed during the end of the last development cycle, passing a
   selinux_state pointer through the SELinux code has a noticeable
   impact on performance, and with the current code it is not strictly
   necessary.

   This simplifies things by referring directly to the single
   selinux_state global variable which should help improve SELinux
   performance.

 - Uninline the unlikely portions of avc_has_perm_noaudit()

   This change was also based on a discussion from the last development
   cycle, and is heavily based on an initial proof of concept patch from
   you. The core issue was that avc_has_perm_noaudit() was not able to
   be inlined, as intended, due to its size. We solved this issue by
   extracting the less frequently hit portions of avc_has_perm_noaudit()
   into a separate function, reducing the size of avc_has_perm_noaudit()
   to the point where the compiler began inlining the function. We also
   took the opportunity to clean up some ugly RCU locking in the code
   that became uglier with the change.

 - Remove the runtime disable functionality

   After several years of work by the userspace and distro folks, we are
   finally in a place where we feel comfortable removing the runtime
   disable functionality which we initially deprecated at the start of
   2020.

   There is plenty of information in the kernel's deprecation (now
   removal) notice, but the main motivation was to be able to safely
   mark the LSM hook structures as '__ro_after_init'.

   LWN also wrote a good summary of the deprecation this morning which
   offers a more detailed history:

        https://lwn.net/SubscriberLink/927463/dcfa0d4ed2872f03

 - Remove the checkreqprot functionality

   The original checkreqprot deprecation notice stated that the removal
   would happen no sooner than June 2021, which means this falls hard
   into the "better late than never" bucket.

   The Kconfig and deprecation notice has more detail on this setting,
   but the basic idea is that we want to ensure that the SELinux policy
   allows for the memory protections actually applied by the kernel, and
   not those requested by the process.

   While we haven't found anyone running a supported distro that is
   affected by this deprecation/removal, anyone who is affected would
   only need to update their policy to reflect the reality of their
   applications' mapping protections.

 - Minor Makefile improvements

   Some minor Makefile improvements to correct some dependency issues
   likely only ever seen by SELinux developers. I expect we will have at
   least one more tweak to the Makefile during the next merge window,
   but it didn't quite make the cutoff this time around.

* tag 'selinux-pr-20230420' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: ensure av_permissions.h is built when needed
  selinux: fix Makefile dependencies of flask.h
  selinux: stop returning node from avc_insert()
  selinux: clean up dead code after removing runtime disable
  selinux: update the file list in MAINTAINERS
  selinux: remove the runtime disable functionality
  selinux: remove the 'checkreqprot' functionality
  selinux: stop passing selinux_state pointers and their offspring
  selinux: uninline unlikely parts of avc_has_perm_noaudit()

Documentation/ABI/obsolete/sysfs-selinux-checkreqprot → Documentation/ABI/removed/sysfs-selinux-checkreqprot

@@ -4,6 +4,9 @@ KernelVersion:	2.6.12-rc2 (predates git)
 Contact:	selinux@vger.kernel.org
 Description:
 
+	REMOVAL UPDATE: The SELinux checkreqprot functionality was removed in
+	March 2023, the original deprecation notice is shown below.
+
 	The selinuxfs "checkreqprot" node allows SELinux to be configured
 	to check the protection requested by userspace for mmap/mprotect
 	calls instead of the actual protection applied by the kernel.

Documentation/ABI/obsolete/sysfs-selinux-disable → Documentation/ABI/removed/sysfs-selinux-disable

@@ -4,6 +4,9 @@ KernelVersion:	2.6.12-rc2 (predates git)
 Contact:	selinux@vger.kernel.org
 Description:
 
+	REMOVAL UPDATE: The SELinux runtime disable functionality was removed
+	in March 2023, the original deprecation notice is shown below.
+
 	The selinuxfs "disable" node allows SELinux to be disabled at runtime
 	prior to a policy being loaded into the kernel.  If disabled via this
 	mechanism, SELinux will remain disabled until the system is rebooted.

MAINTAINERS

@@ -18822,8 +18822,8 @@ S:	Supported
 W:	https://selinuxproject.org
 W:	https://github.com/SELinuxProject
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux.git
-F:	Documentation/ABI/obsolete/sysfs-selinux-checkreqprot
-F:	Documentation/ABI/obsolete/sysfs-selinux-disable
+F:	Documentation/ABI/removed/sysfs-selinux-checkreqprot
+F:	Documentation/ABI/removed/sysfs-selinux-disable
 F:	Documentation/admin-guide/LSM/SELinux.rst
 F:	include/trace/events/avc.h
 F:	include/uapi/linux/selinux_netlink.h

include/linux/lsm_hooks.h

@@ -1740,36 +1740,6 @@ extern struct lsm_info __start_early_lsm_info[], __end_early_lsm_info[];
 		__used __section(".early_lsm_info.init")		\
 		__aligned(sizeof(unsigned long))
 
-#ifdef CONFIG_SECURITY_SELINUX_DISABLE
-/*
- * Assuring the safety of deleting a security module is up to
- * the security module involved. This may entail ordering the
- * module's hook list in a particular way, refusing to disable
- * the module once a policy is loaded or any number of other
- * actions better imagined than described.
- *
- * The name of the configuration option reflects the only module
- * that currently uses the mechanism. Any developer who thinks
- * disabling their module is a good idea needs to be at least as
- * careful as the SELinux team.
- */
-static inline void security_delete_hooks(struct security_hook_list *hooks,
-						int count)
-{
-	int i;
-
-	for (i = 0; i < count; i++)
-		hlist_del_rcu(&hooks[i].list);
-}
-#endif /* CONFIG_SECURITY_SELINUX_DISABLE */
-
-/* Currently required to handle SELinux runtime hook disable. */
-#ifdef CONFIG_SECURITY_WRITABLE_HOOKS
-#define __lsm_ro_after_init
-#else
-#define __lsm_ro_after_init	__ro_after_init
-#endif /* CONFIG_SECURITY_WRITABLE_HOOKS */
-
 extern int lsm_inode_alloc(struct inode *inode);
 
 #endif /* ! __LINUX_LSM_HOOKS_H */

security/Kconfig

@@ -32,11 +32,6 @@ config SECURITY
 
 	  If you are unsure how to answer this question, answer N.
 
-config SECURITY_WRITABLE_HOOKS
-	depends on SECURITY
-	bool
-	default n
-
 config SECURITYFS
 	bool "Enable the securityfs filesystem"
 	help

security/apparmor/lsm.c

@@ -1209,13 +1209,13 @@ static int apparmor_inet_conn_request(const struct sock *sk, struct sk_buff *skb
 /*
  * The cred blob is a pointer to, not an instance of, an aa_label.
  */
-struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
+struct lsm_blob_sizes apparmor_blob_sizes __ro_after_init = {
 	.lbs_cred = sizeof(struct aa_label *),
 	.lbs_file = sizeof(struct aa_file_ctx),
 	.lbs_task = sizeof(struct aa_task_ctx),
 };
 
-static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
+static struct security_hook_list apparmor_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
 	LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
 	LSM_HOOK_INIT(capget, apparmor_capget),
@@ -1427,7 +1427,7 @@ static const struct kernel_param_ops param_ops_aaintbool = {
 	.get = param_get_aaintbool
 };
 /* Boot time disable flag */
-static int apparmor_enabled __lsm_ro_after_init = 1;
+static int apparmor_enabled __ro_after_init = 1;
 module_param_named(enabled, apparmor_enabled, aaintbool, 0444);
 
 static int __init apparmor_enabled_setup(char *str)

security/bpf/hooks.c

@@ -6,7 +6,7 @@
 #include <linux/lsm_hooks.h>
 #include <linux/bpf_lsm.h>
 
-static struct security_hook_list bpf_lsm_hooks[] __lsm_ro_after_init = {
+static struct security_hook_list bpf_lsm_hooks[] __ro_after_init = {
 	#define LSM_HOOK(RET, DEFAULT, NAME, ...) \
 	LSM_HOOK_INIT(NAME, bpf_lsm_##NAME),
 	#include <linux/lsm_hook_defs.h>
@@ -22,7 +22,7 @@ static int __init bpf_lsm_init(void)
 	return 0;
 }
 
-struct lsm_blob_sizes bpf_lsm_blob_sizes __lsm_ro_after_init = {
+struct lsm_blob_sizes bpf_lsm_blob_sizes __ro_after_init = {
 	.lbs_inode = sizeof(struct bpf_storage_blob),
 	.lbs_task = sizeof(struct bpf_storage_blob),
 };

security/commoncap.c

@@ -1440,7 +1440,7 @@ int cap_mmap_file(struct file *file, unsigned long reqprot,
 
 #ifdef CONFIG_SECURITY
 
-static struct security_hook_list capability_hooks[] __lsm_ro_after_init = {
+static struct security_hook_list capability_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(capable, cap_capable),
 	LSM_HOOK_INIT(settime, cap_settime),
 	LSM_HOOK_INIT(ptrace_access_check, cap_ptrace_access_check),

security/landlock/cred.c

@@ -34,7 +34,7 @@ static void hook_cred_free(struct cred *const cred)
 		landlock_put_ruleset_deferred(dom);
 }
 
-static struct security_hook_list landlock_hooks[] __lsm_ro_after_init = {
+static struct security_hook_list landlock_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(cred_prepare, hook_cred_prepare),
 	LSM_HOOK_INIT(cred_free, hook_cred_free),
 };

security/landlock/fs.c

@@ -1280,7 +1280,7 @@ static int hook_file_truncate(struct file *const file)
 	return -EACCES;
 }
 
-static struct security_hook_list landlock_hooks[] __lsm_ro_after_init = {
+static struct security_hook_list landlock_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(inode_free_security, hook_inode_free_security),
 
 	LSM_HOOK_INIT(sb_delete, hook_sb_delete),

security/landlock/ptrace.c

@@ -108,7 +108,7 @@ static int hook_ptrace_traceme(struct task_struct *const parent)
 	return task_ptrace(parent, current);
 }
 
-static struct security_hook_list landlock_hooks[] __lsm_ro_after_init = {
+static struct security_hook_list landlock_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(ptrace_access_check, hook_ptrace_access_check),
 	LSM_HOOK_INIT(ptrace_traceme, hook_ptrace_traceme),
 };

security/landlock/setup.c

@@ -15,9 +15,9 @@
 #include "ptrace.h"
 #include "setup.h"
 
-bool landlock_initialized __lsm_ro_after_init = false;
+bool landlock_initialized __ro_after_init = false;
 
-struct lsm_blob_sizes landlock_blob_sizes __lsm_ro_after_init = {
+struct lsm_blob_sizes landlock_blob_sizes __ro_after_init = {
 	.lbs_cred = sizeof(struct landlock_cred_security),
 	.lbs_file = sizeof(struct landlock_file_security),
 	.lbs_inode = sizeof(struct landlock_inode_security),

security/loadpin/loadpin.c

@@ -214,7 +214,7 @@ static int loadpin_load_data(enum kernel_load_data_id id, bool contents)
 	return loadpin_check(NULL, (enum kernel_read_file_id) id);
 }
 
-static struct security_hook_list loadpin_hooks[] __lsm_ro_after_init = {
+static struct security_hook_list loadpin_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(sb_free_security, loadpin_sb_free_security),
 	LSM_HOOK_INIT(kernel_read_file, loadpin_read_file),
 	LSM_HOOK_INIT(kernel_load_data, loadpin_load_data),

security/lockdown/lockdown.c

@@ -71,7 +71,7 @@ static int lockdown_is_locked_down(enum lockdown_reason what)
 	return 0;
 }
 
-static struct security_hook_list lockdown_hooks[] __lsm_ro_after_init = {
+static struct security_hook_list lockdown_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(locked_down, lockdown_is_locked_down),
 };
 

security/security.c

@@ -74,14 +74,14 @@ const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX+1] = {
 	[LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality",
 };
 
-struct security_hook_heads security_hook_heads __lsm_ro_after_init;
+struct security_hook_heads security_hook_heads __ro_after_init;
 static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain);
 
 static struct kmem_cache *lsm_file_cache;
 static struct kmem_cache *lsm_inode_cache;
 
 char *lsm_names;
-static struct lsm_blob_sizes blob_sizes __lsm_ro_after_init;
+static struct lsm_blob_sizes blob_sizes __ro_after_init;
 
 /* Boot-time LSM user choice */
 static __initdata const char *chosen_lsm_order;

security/selinux/Kconfig

@@ -23,30 +23,6 @@ config SECURITY_SELINUX_BOOTPARAM
 
 	  If you are unsure how to answer this question, answer N.
 
-config SECURITY_SELINUX_DISABLE
-	bool "NSA SELinux runtime disable"
-	depends on SECURITY_SELINUX
-	select SECURITY_WRITABLE_HOOKS
-	default n
-	help
-	  This option enables writing to a selinuxfs node 'disable', which
-	  allows SELinux to be disabled at runtime prior to the policy load.
-	  SELinux will then remain disabled until the next boot.
-	  This option is similar to the selinux=0 boot parameter, but is to
-	  support runtime disabling of SELinux, e.g. from /sbin/init, for
-	  portability across platforms where boot parameters are difficult
-	  to employ.
-
-	  NOTE: selecting this option will disable the '__ro_after_init'
-	  kernel hardening feature for security hooks.   Please consider
-	  using the selinux=0 boot parameter instead of enabling this
-	  option.
-
-	  WARNING: this option is deprecated and will be removed in a future
-	  kernel release.
-
-	  If you are unsure how to answer this question, answer N.
-
 config SECURITY_SELINUX_DEVELOP
 	bool "NSA SELinux Development Support"
 	depends on SECURITY_SELINUX
@@ -70,29 +46,6 @@ config SECURITY_SELINUX_AVC_STATS
 	  /sys/fs/selinux/avc/cache_stats, which may be monitored via
 	  tools such as avcstat.
 
-config SECURITY_SELINUX_CHECKREQPROT_VALUE
-	int "NSA SELinux checkreqprot default value"
-	depends on SECURITY_SELINUX
-	range 0 1
-	default 0
-	help
-	  This option sets the default value for the 'checkreqprot' flag
-	  that determines whether SELinux checks the protection requested
-	  by the application or the protection that will be applied by the
-	  kernel (including any implied execute for read-implies-exec) for
-	  mmap and mprotect calls.  If this option is set to 0 (zero),
-	  SELinux will default to checking the protection that will be applied
-	  by the kernel.  If this option is set to 1 (one), SELinux will
-	  default to checking the protection requested by the application.
-	  The checkreqprot flag may be changed from the default via the
-	  'checkreqprot=' boot parameter.  It may also be changed at runtime
-	  via /sys/fs/selinux/checkreqprot if authorized by policy.
-
-	  WARNING: this option is deprecated and will be removed in a future
-	  kernel release.
-
-	  If you are unsure how to answer this question, answer 0.
-
 config SECURITY_SELINUX_SIDTAB_HASH_BITS
 	int "NSA SELinux sidtab hashtable size"
 	depends on SECURITY_SELINUX

security/selinux/Makefile

@@ -23,8 +23,8 @@ ccflags-y := -I$(srctree)/security/selinux -I$(srctree)/security/selinux/include
 $(addprefix $(obj)/,$(selinux-y)): $(obj)/flask.h
 
 quiet_cmd_flask = GEN     $(obj)/flask.h $(obj)/av_permissions.h
-      cmd_flask = scripts/selinux/genheaders/genheaders $(obj)/flask.h $(obj)/av_permissions.h
+      cmd_flask = $< $(obj)/flask.h $(obj)/av_permissions.h
 
 targets += flask.h av_permissions.h
-$(obj)/flask.h: $(src)/include/classmap.h FORCE
+$(obj)/flask.h $(obj)/av_permissions.h &: scripts/selinux/genheaders/genheaders FORCE
 	$(call if_changed,flask)