Merge tag 'blob-stacking-security-next' of https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into next-general

LSM: Module stacking for SARA and Landlock

The combined series of LSM refactoring and addition of blob-sharing for
SARA and Landlock.

From Casey:

v5: Include Kees Cook's rework of the lsm command
    line interface.
v4: Finer granularity in the patches and other
    cleanups suggested by Kees Cook.
    Removed dead code created by the removal of SELinux
    credential blob poisoning.
v3: Add ipc blob for SARA and task blob for Landlock.
    Removing the SELinux cred blob pointer poisoning
    results selinux_is_enabled() being unused, so it and
    all it's overhead has been removed.
    Broke up the cred infrastructure patch.
v2: Reduce the patchset to what is required to support
    the proposed SARA and LandLock security modules

The SARA security module is intended to be used
in conjunction with other security modules. It requires
state to be maintained for the credential, which
in turn requires a mechanism for sharing the credential
security blob. It also uses the ipc security blob. The
module also requires mechanism for user space manipulation
of the credential information, hence an additional
subdirectory in /proc/.../attr.

The LandLock security module provides user configurable
policy in the secmark mechanism. It requires data in
the credential, file, inode and task security blobs. For
this to be used along side the existing "major" security
modules mechanism for sharing these blobs are provided.

A side effect of providing sharing of the crendential
security blob is that the TOMOYO module can be used at
the same time as the other "major" modules.

The mechanism for configuring which security modules are
enabled has to change when stacking in enabled. Any
module that uses just the security blobs that are shared
can be selected. Additionally, one other "major" module
can be selected.

The security module stacking issues around networking and
IPC are not addressed here as they are beyond what is
required for TOMOYO, SARA and LandLock.

1 files changed, 89 insertions, 256 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index f0e36c3492ba..d98e1d8d18f6 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -79,7 +79,6 @@
 #include <linux/personality.h>
 #include <linux/audit.h>
 #include <linux/string.h>
-#include <linux/selinux.h>
 #include <linux/mutex.h>
 #include <linux/posix-timers.h>
 #include <linux/syslog.h>
@@ -121,9 +120,8 @@ __setup("enforcing=", enforcing_setup);
 #define selinux_enforcing_boot 1
 #endif
 
+int selinux_enabled __lsm_ro_after_init = 1;
 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
-int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
-
 static int __init selinux_enabled_setup(char *str)
 {
 	unsigned long enabled;
@@ -132,8 +130,6 @@ static int __init selinux_enabled_setup(char *str)
 	return 1;
 }
 __setup("selinux=", selinux_enabled_setup);
-#else
-int selinux_enabled = 1;
 #endif
 
 static unsigned int selinux_checkreqprot_boot =
@@ -149,9 +145,6 @@ static int __init checkreqprot_setup(char *str)
 }
 __setup("checkreqprot=", checkreqprot_setup);
 
-static struct kmem_cache *sel_inode_cache;
-static struct kmem_cache *file_security_cache;
-
 /**
  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
  *
@@ -214,12 +207,9 @@ static void cred_init_security(void)
 	struct cred *cred = (struct cred *) current->real_cred;
 	struct task_security_struct *tsec;
 
-	tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
-	if (!tsec)
-		panic("SELinux:  Failed to initialize initial task.\n");
-
+	lsm_early_cred(cred);
+	tsec = selinux_cred(cred);
 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
-	cred->security = tsec;
 }
 
 /*
@@ -229,7 +219,7 @@ static inline u32 cred_sid(const struct cred *cred)
 {
 	const struct task_security_struct *tsec;
 
-	tsec = cred->security;
+	tsec = selinux_cred(cred);
 	return tsec->sid;
 }
 
@@ -250,13 +240,9 @@ static inline u32 task_sid(const struct task_struct *task)
 
 static int inode_alloc_security(struct inode *inode)
 {
-	struct inode_security_struct *isec;
+	struct inode_security_struct *isec = selinux_inode(inode);
 	u32 sid = current_sid();
 
-	isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
-	if (!isec)
-		return -ENOMEM;
-
 	spin_lock_init(&isec->lock);
 	INIT_LIST_HEAD(&isec->list);
 	isec->inode = inode;
@@ -264,7 +250,6 @@ static int inode_alloc_security(struct inode *inode)
 	isec->sclass = SECCLASS_FILE;
 	isec->task_sid = sid;
 	isec->initialized = LABEL_INVALID;
-	inode->i_security = isec;
 
 	return 0;
 }
@@ -281,7 +266,7 @@ static int __inode_security_revalidate(struct inode *inode,
 				       struct dentry *dentry,
 				       bool may_sleep)
 {
-	struct inode_security_struct *isec = inode->i_security;
+	struct inode_security_struct *isec = selinux_inode(inode);
 
 	might_sleep_if(may_sleep);
 
@@ -302,7 +287,7 @@ static int __inode_security_revalidate(struct inode *inode,
 
 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 {
-	return inode->i_security;
+	return selinux_inode(inode);
 }
 
 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
@@ -312,7 +297,7 @@ static struct inode_security_struct *inode_security_rcu(struct inode *inode, boo
 	error = __inode_security_revalidate(inode, NULL, !rcu);
 	if (error)
 		return ERR_PTR(error);
-	return inode->i_security;
+	return selinux_inode(inode);
 }
 
 /*
@@ -321,14 +306,14 @@ static struct inode_security_struct *inode_security_rcu(struct inode *inode, boo
 static struct inode_security_struct *inode_security(struct inode *inode)
 {
 	__inode_security_revalidate(inode, NULL, true);
-	return inode->i_security;
+	return selinux_inode(inode);
 }
 
 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 {
 	struct inode *inode = d_backing_inode(dentry);
 
-	return inode->i_security;
+	return selinux_inode(inode);
 }
 
 /*
@@ -339,22 +324,17 @@ static struct inode_security_struct *backing_inode_security(struct dentry *dentr
 	struct inode *inode = d_backing_inode(dentry);
 
 	__inode_security_revalidate(inode, dentry, true);
-	return inode->i_security;
-}
-
-static void inode_free_rcu(struct rcu_head *head)
-{
-	struct inode_security_struct *isec;
-
-	isec = container_of(head, struct inode_security_struct, rcu);
-	kmem_cache_free(sel_inode_cache, isec);
+	return selinux_inode(inode);
 }
 
 static void inode_free_security(struct inode *inode)
 {
-	struct inode_security_struct *isec = inode->i_security;
-	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
+	struct inode_security_struct *isec = selinux_inode(inode);
+	struct superblock_security_struct *sbsec;
 
+	if (!isec)
+		return;
+	sbsec = inode->i_sb->s_security;
 	/*
 	 * As not all inode security structures are in a list, we check for
 	 * empty list outside of the lock to make sure that we won't waste
@@ -370,42 +350,19 @@ static void inode_free_security(struct inode *inode)
 		list_del_init(&isec->list);
 		spin_unlock(&sbsec->isec_lock);
 	}
-
-	/*
-	 * The inode may still be referenced in a path walk and
-	 * a call to selinux_inode_permission() can be made
-	 * after inode_free_security() is called. Ideally, the VFS
-	 * wouldn't do this, but fixing that is a much harder
-	 * job. For now, simply free the i_security via RCU, and
-	 * leave the current inode->i_security pointer intact.
-	 * The inode will be freed after the RCU grace period too.
-	 */
-	call_rcu(&isec->rcu, inode_free_rcu);
 }
 
 static int file_alloc_security(struct file *file)
 {
-	struct file_security_struct *fsec;
+	struct file_security_struct *fsec = selinux_file(file);
 	u32 sid = current_sid();
 
-	fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
-	if (!fsec)
-		return -ENOMEM;
-
 	fsec->sid = sid;
 	fsec->fown_sid = sid;
-	file->f_security = fsec;
 
 	return 0;
 }
 
-static void file_free_security(struct file *file)
-{
-	struct file_security_struct *fsec = file->f_security;
-	file->f_security = NULL;
-	kmem_cache_free(file_security_cache, fsec);
-}
-
 static int superblock_alloc_security(struct super_block *sb)
 {
 	struct superblock_security_struct *sbsec;
@@ -501,7 +458,7 @@ static int may_context_mount_sb_relabel(u32 sid,
 			struct superblock_security_struct *sbsec,
 			const struct cred *cred)
 {
-	const struct task_security_struct *tsec = cred->security;
+	const struct task_security_struct *tsec = selinux_cred(cred);
 	int rc;
 
 	rc = avc_has_perm(&selinux_state,
@@ -520,7 +477,7 @@ static int may_context_mount_inode_relabel(u32 sid,
 			struct superblock_security_struct *sbsec,
 			const struct cred *cred)
 {
-	const struct task_security_struct *tsec = cred->security;
+	const struct task_security_struct *tsec = selinux_cred(cred);
 	int rc;
 	rc = avc_has_perm(&selinux_state,
 			  tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
@@ -1374,7 +1331,7 @@ static int selinux_genfs_get_sid(struct dentry *dentry,
 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
 {
 	struct superblock_security_struct *sbsec = NULL;
-	struct inode_security_struct *isec = inode->i_security;
+	struct inode_security_struct *isec = selinux_inode(inode);
 	u32 task_sid, sid = 0;
 	u16 sclass;
 	struct dentry *dentry;
@@ -1674,7 +1631,7 @@ static int inode_has_perm(const struct cred *cred,
 		return 0;
 
 	sid = cred_sid(cred);
-	isec = inode->i_security;
+	isec = selinux_inode(inode);
 
 	return avc_has_perm(&selinux_state,
 			    sid, isec->sid, isec->sclass, perms, adp);
@@ -1740,7 +1697,7 @@ static int file_has_perm(const struct cred *cred,
 			 struct file *file,
 			 u32 av)
 {
-	struct file_security_struct *fsec = file->f_security;
+	struct file_security_struct *fsec = selinux_file(file);
 	struct inode *inode = file_inode(file);
 	struct common_audit_data ad;
 	u32 sid = cred_sid(cred);
@@ -1806,7 +1763,7 @@ static int may_create(struct inode *dir,
 		      struct dentry *dentry,
 		      u16 tclass)
 {
-	const struct task_security_struct *tsec = current_security();
+	const struct task_security_struct *tsec = selinux_cred(current_cred());
 	struct inode_security_struct *dsec;
 	struct superblock_security_struct *sbsec;
 	u32 sid, newsid;
@@ -1828,7 +1785,7 @@ static int may_create(struct inode *dir,
 	if (rc)
 		return rc;
 
-	rc = selinux_determine_inode_label(current_security(), dir,
+	rc = selinux_determine_inode_label(selinux_cred(current_cred()), dir,
 					   &dentry->d_name, tclass, &newsid);
 	if (rc)
 		return rc;
@@ -2084,7 +2041,7 @@ static int selinux_binder_transfer_file(struct task_struct *from,
 					struct file *file)
 {
 	u32 sid = task_sid(to);
-	struct file_security_struct *fsec = file->f_security;
+	struct file_security_struct *fsec = selinux_file(file);
 	struct dentry *dentry = file->f_path.dentry;
 	struct inode_security_struct *isec;
 	struct common_audit_data ad;
@@ -2335,8 +2292,8 @@ static int selinux_bprm_set_creds(struct linux_binprm *bprm)
 	if (bprm->called_set_creds)
 		return 0;
 
-	old_tsec = current_security();
-	new_tsec = bprm->cred->security;
+	old_tsec = selinux_cred(current_cred());
+	new_tsec = selinux_cred(bprm->cred);
 	isec = inode_security(inode);
 
 	/* Default to the current task SID. */
@@ -2500,7 +2457,7 @@ static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
 	struct rlimit *rlim, *initrlim;
 	int rc, i;
 
-	new_tsec = bprm->cred->security;
+	new_tsec = selinux_cred(bprm->cred);
 	if (new_tsec->sid == new_tsec->osid)
 		return;
 
@@ -2543,7 +2500,7 @@ static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
  */
 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
 {
-	const struct task_security_struct *tsec = current_security();
+	const struct task_security_struct *tsec = selinux_cred(current_cred());
 	struct itimerval itimer;
 	u32 osid, sid;
 	int rc, i;
@@ -2780,7 +2737,7 @@ static int selinux_dentry_init_security(struct dentry *dentry, int mode,
 	u32 newsid;
 	int rc;
 
-	rc = selinux_determine_inode_label(current_security(),
+	rc = selinux_determine_inode_label(selinux_cred(current_cred()),
 					   d_inode(dentry->d_parent), name,
 					   inode_mode_to_security_class(mode),
 					   &newsid);
@@ -2800,14 +2757,14 @@ static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
 	int rc;
 	struct task_security_struct *tsec;
 
-	rc = selinux_determine_inode_label(old->security,
+	rc = selinux_determine_inode_label(selinux_cred(old),
 					   d_inode(dentry->d_parent), name,
 					   inode_mode_to_security_class(mode),
 					   &newsid);
 	if (rc)
 		return rc;
 
-	tsec = new->security;
+	tsec = selinux_cred(new);
 	tsec->create_sid = newsid;
 	return 0;
 }
@@ -2817,7 +2774,7 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
 				       const char **name,
 				       void **value, size_t *len)
 {
-	const struct task_security_struct *tsec = current_security();
+	const struct task_security_struct *tsec = selinux_cred(current_cred());
 	struct superblock_security_struct *sbsec;
 	u32 newsid, clen;
 	int rc;
@@ -2827,7 +2784,7 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
 
 	newsid = tsec->create_sid;
 
-	rc = selinux_determine_inode_label(current_security(),
+	rc = selinux_determine_inode_label(selinux_cred(current_cred()),
 		dir, qstr,
 		inode_mode_to_security_class(inode->i_mode),
 		&newsid);
@@ -2836,7 +2793,7 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
 
 	/* Possibly defer initialization to selinux_complete_init. */
 	if (sbsec->flags & SE_SBINITIALIZED) {
-		struct inode_security_struct *isec = inode->i_security;
+		struct inode_security_struct *isec = selinux_inode(inode);
 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
 		isec->sid = newsid;
 		isec->initialized = LABEL_INITIALIZED;
@@ -2936,7 +2893,7 @@ static noinline int audit_inode_permission(struct inode *inode,
 					   unsigned flags)
 {
 	struct common_audit_data ad;
-	struct inode_security_struct *isec = inode->i_security;
+	struct inode_security_struct *isec = selinux_inode(inode);
 	int rc;
 
 	ad.type = LSM_AUDIT_DATA_INODE;
@@ -3289,7 +3246,7 @@ static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
 			return -ENOMEM;
 	}
 
-	tsec = new_creds->security;
+	tsec = selinux_cred(new_creds);
 	/* Get label from overlay inode and set it in create_sid */
 	selinux_inode_getsecid(d_inode(src), &sid);
 	tsec->create_sid = sid;
@@ -3330,7 +3287,7 @@ static int selinux_revalidate_file_permission(struct file *file, int mask)
 static int selinux_file_permission(struct file *file, int mask)
 {
 	struct inode *inode = file_inode(file);
-	struct file_security_struct *fsec = file->f_security;
+	struct file_security_struct *fsec = selinux_file(file);
 	struct inode_security_struct *isec;
 	u32 sid = current_sid();
 
@@ -3352,11 +3309,6 @@ static int selinux_file_alloc_security(struct file *file)
 	return file_alloc_security(file);
 }
 
-static void selinux_file_free_security(struct file *file)
-{
-	file_free_security(file);
-}
-
 /*
  * Check whether a task has the ioctl permission and cmd
  * operation to an inode.
@@ -3365,7 +3317,7 @@ static int ioctl_has_perm(const struct cred *cred, struct file *file,
 		u32 requested, u16 cmd)
 {
 	struct common_audit_data ad;
-	struct file_security_struct *fsec = file->f_security;
+	struct file_security_struct *fsec = selinux_file(file);
 	struct inode *inode = file_inode(file);
 	struct inode_security_struct *isec;
 	struct lsm_ioctlop_audit ioctl;
@@ -3617,7 +3569,7 @@ static void selinux_file_set_fowner(struct file *file)
 {
 	struct file_security_struct *fsec;
 
-	fsec = file->f_security;
+	fsec = selinux_file(file);
 	fsec->fown_sid = current_sid();
 }
 
@@ -3632,7 +3584,7 @@ static int selinux_file_send_sigiotask(struct task_struct *tsk,
 	/* struct fown_struct is never outside the context of a struct file */
 	file = container_of(fown, struct file, f_owner);
 
-	fsec = file->f_security;
+	fsec = selinux_file(file);
 
 	if (!signum)
 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
@@ -3656,7 +3608,7 @@ static int selinux_file_open(struct file *file)
 	struct file_security_struct *fsec;
 	struct inode_security_struct *isec;
 
-	fsec = file->f_security;
+	fsec = selinux_file(file);
 	isec = inode_security(file_inode(file));
 	/*
 	 * Save inode label and policy sequence number
@@ -3690,52 +3642,15 @@ static int selinux_task_alloc(struct task_struct *task,
 }
 
 /*
- * allocate the SELinux part of blank credentials
- */
-static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
-{
-	struct task_security_struct *tsec;
-
-	tsec = kzalloc(sizeof(struct task_security_struct), gfp);
-	if (!tsec)
-		return -ENOMEM;
-
-	cred->security = tsec;
-	return 0;
-}
-
-/*
- * detach and free the LSM part of a set of credentials
- */
-static void selinux_cred_free(struct cred *cred)
-{
-	struct task_security_struct *tsec = cred->security;
-
-	/*
-	 * cred->security == NULL if security_cred_alloc_blank() or
-	 * security_prepare_creds() returned an error.
-	 */
-	BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
-	cred->security = (void *) 0x7UL;
-	kfree(tsec);
-}
-
-/*
  * prepare a new set of credentials for modification
  */
 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
 				gfp_t gfp)
 {
-	const struct task_security_struct *old_tsec;
-	struct task_security_struct *tsec;
-
-	old_tsec = old->security;
+	const struct task_security_struct *old_tsec = selinux_cred(old);
+	struct task_security_struct *tsec = selinux_cred(new);
 
-	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
-	if (!tsec)
-		return -ENOMEM;
-
-	new->security = tsec;
+	*tsec = *old_tsec;
 	return 0;
 }
 
@@ -3744,8 +3659,8 @@ static int selinux_cred_prepare(struct cred *new, const struct cred *old,
  */
 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
 {
-	const struct task_security_struct *old_tsec = old->security;
-	struct task_security_struct *tsec = new->security;
+	const struct task_security_struct *old_tsec = selinux_cred(old);
+	struct task_security_struct *tsec = selinux_cred(new);
 
 	*tsec = *old_tsec;
 }
@@ -3761,7 +3676,7 @@ static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
  */
 static int selinux_kernel_act_as(struct cred *new, u32 secid)
 {
-	struct task_security_struct *tsec = new->security;
+	struct task_security_struct *tsec = selinux_cred(new);
 	u32 sid = current_sid();
 	int ret;
 
@@ -3786,7 +3701,7 @@ static int selinux_kernel_act_as(struct cred *new, u32 secid)
 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
 {
 	struct inode_security_struct *isec = inode_security(inode);
-	struct task_security_struct *tsec = new->security;
+	struct task_security_struct *tsec = selinux_cred(new);
 	u32 sid = current_sid();
 	int ret;
 
@@ -3832,7 +3747,7 @@ static int selinux_kernel_module_from_file(struct file *file)
 	ad.type = LSM_AUDIT_DATA_FILE;
 	ad.u.file = file;
 
-	fsec = file->f_security;
+	fsec = selinux_file(file);
 	if (sid != fsec->sid) {
 		rc = avc_has_perm(&selinux_state,
 				  sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
@@ -3998,7 +3913,7 @@ static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
 static void selinux_task_to_inode(struct task_struct *p,
 				  struct inode *inode)
 {
-	struct inode_security_struct *isec = inode->i_security;
+	struct inode_security_struct *isec = selinux_inode(inode);
 	u32 sid = task_sid(p);
 
 	spin_lock(&isec->lock);
@@ -4335,7 +4250,7 @@ static int sock_has_perm(struct sock *sk, u32 perms)
 static int selinux_socket_create(int family, int type,
 				 int protocol, int kern)
 {
-	const struct task_security_struct *tsec = current_security();
+	const struct task_security_struct *tsec = selinux_cred(current_cred());
 	u32 newsid;
 	u16 secclass;
 	int rc;
@@ -4355,7 +4270,7 @@ static int selinux_socket_create(int family, int type,
 static int selinux_socket_post_create(struct socket *sock, int family,
 				      int type, int protocol, int kern)
 {
-	const struct task_security_struct *tsec = current_security();
+	const struct task_security_struct *tsec = selinux_cred(current_cred());
 	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
 	struct sk_security_struct *sksec;
 	u16 sclass = socket_type_to_security_class(family, type, protocol);
@@ -5236,7 +5151,7 @@ static int selinux_secmark_relabel_packet(u32 sid)
 	const struct task_security_struct *__tsec;
 	u32 tsid;
 
-	__tsec = current_security();
+	__tsec = selinux_cred(current_cred());
 	tsid = __tsec->sid;
 
 	return avc_has_perm(&selinux_state,
@@ -5711,51 +5626,22 @@ static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
 	return selinux_nlmsg_perm(sk, skb);
 }
 
-static int ipc_alloc_security(struct kern_ipc_perm *perm,
-			      u16 sclass)
+static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
 {
-	struct ipc_security_struct *isec;
-
-	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
-	if (!isec)
-		return -ENOMEM;
-
 	isec->sclass = sclass;
 	isec->sid = current_sid();
-	perm->security = isec;
-
-	return 0;
-}
-
-static void ipc_free_security(struct kern_ipc_perm *perm)
-{
-	struct ipc_security_struct *isec = perm->security;
-	perm->security = NULL;
-	kfree(isec);
 }
 
 static int msg_msg_alloc_security(struct msg_msg *msg)
 {
 	struct msg_security_struct *msec;
 
-	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
-	if (!msec)
-		return -ENOMEM;
-
+	msec = selinux_msg_msg(msg);
 	msec->sid = SECINITSID_UNLABELED;
-	msg->security = msec;
 
 	return 0;
 }
 
-static void msg_msg_free_security(struct msg_msg *msg)
-{
-	struct msg_security_struct *msec = msg->security;
-
-	msg->security = NULL;
-	kfree(msec);
-}
-
 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
 			u32 perms)
 {
@@ -5763,7 +5649,7 @@ static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
 	struct common_audit_data ad;
 	u32 sid = current_sid();
 
-	isec = ipc_perms->security;
+	isec = selinux_ipc(ipc_perms);
 
 	ad.type = LSM_AUDIT_DATA_IPC;
 	ad.u.ipc_id = ipc_perms->key;
@@ -5777,11 +5663,6 @@ static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
 	return msg_msg_alloc_security(msg);
 }
 
-static void selinux_msg_msg_free_security(struct msg_msg *msg)
-{
-	msg_msg_free_security(msg);
-}
-
 /* message queue security operations */
 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
 {
@@ -5790,11 +5671,8 @@ static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
 	u32 sid = current_sid();
 	int rc;
 
-	rc = ipc_alloc_security(msq, SECCLASS_MSGQ);
-	if (rc)
-		return rc;
-
-	isec = msq->security;
+	isec = selinux_ipc(msq);
+	ipc_init_security(isec, SECCLASS_MSGQ);
 
 	ad.type = LSM_AUDIT_DATA_IPC;
 	ad.u.ipc_id = msq->key;
@@ -5802,16 +5680,7 @@ static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
 	rc = avc_has_perm(&selinux_state,
 			  sid, isec->sid, SECCLASS_MSGQ,
 			  MSGQ__CREATE, &ad);
-	if (rc) {
-		ipc_free_security(msq);
-		return rc;
-	}
-	return 0;
-}
-
-static void selinux_msg_queue_free_security(struct kern_ipc_perm *msq)
-{
-	ipc_free_security(msq);
+	return rc;
 }
 
 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
@@ -5820,7 +5689,7 @@ static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
 	struct common_audit_data ad;
 	u32 sid = current_sid();
 
-	isec = msq->security;
+	isec = selinux_ipc(msq);
 
 	ad.type = LSM_AUDIT_DATA_IPC;
 	ad.u.ipc_id = msq->key;
@@ -5869,8 +5738,8 @@ static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *m
 	u32 sid = current_sid();
 	int rc;
 
-	isec = msq->security;
-	msec = msg->security;
+	isec = selinux_ipc(msq);
+	msec = selinux_msg_msg(msg);
 
 	/*
 	 * First time through, need to assign label to the message
@@ -5917,8 +5786,8 @@ static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *m
 	u32 sid = task_sid(target);
 	int rc;
 
-	isec = msq->security;
-	msec = msg->security;
+	isec = selinux_ipc(msq);
+	msec = selinux_msg_msg(msg);
 
 	ad.type = LSM_AUDIT_DATA_IPC;
 	ad.u.ipc_id = msq->key;
@@ -5941,11 +5810,8 @@ static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
 	u32 sid = current_sid();
 	int rc;
 
-	rc = ipc_alloc_security(shp, SECCLASS_SHM);
-	if (rc)
-		return rc;
-
-	isec = shp->security;
+	isec = selinux_ipc(shp);
+	ipc_init_security(isec, SECCLASS_SHM);
 
 	ad.type = LSM_AUDIT_DATA_IPC;
 	ad.u.ipc_id = shp->key;
@@ -5953,16 +5819,7 @@ static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
 	rc = avc_has_perm(&selinux_state,
 			  sid, isec->sid, SECCLASS_SHM,
 			  SHM__CREATE, &ad);
-	if (rc) {
-		ipc_free_security(shp);
-		return rc;
-	}
-	return 0;
-}
-
-static void selinux_shm_free_security(struct kern_ipc_perm *shp)
-{
-	ipc_free_security(shp);
+	return rc;
 }
 
 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
@@ -5971,7 +5828,7 @@ static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
 	struct common_audit_data ad;
 	u32 sid = current_sid();
 
-	isec = shp->security;
+	isec = selinux_ipc(shp);
 
 	ad.type = LSM_AUDIT_DATA_IPC;
 	ad.u.ipc_id = shp->key;
@@ -6038,11 +5895,8 @@ static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
 	u32 sid = current_sid();
 	int rc;
 
-	rc = ipc_alloc_security(sma, SECCLASS_SEM);
-	if (rc)
-		return rc;
-
-	isec = sma->security;
+	isec = selinux_ipc(sma);
+	ipc_init_security(isec, SECCLASS_SEM);
 
 	ad.type = LSM_AUDIT_DATA_IPC;
 	ad.u.ipc_id = sma->key;
@@ -6050,16 +5904,7 @@ static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
 	rc = avc_has_perm(&selinux_state,
 			  sid, isec->sid, SECCLASS_SEM,
 			  SEM__CREATE, &ad);
-	if (rc) {
-		ipc_free_security(sma);
-		return rc;
-	}
-	return 0;
-}
-
-static void selinux_sem_free_security(struct kern_ipc_perm *sma)
-{
-	ipc_free_security(sma);
+	return rc;
 }
 
 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
@@ -6068,7 +5913,7 @@ static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
 	struct common_audit_data ad;
 	u32 sid = current_sid();
 
-	isec = sma->security;
+	isec = selinux_ipc(sma);
 
 	ad.type = LSM_AUDIT_DATA_IPC;
 	ad.u.ipc_id = sma->key;
@@ -6154,7 +5999,7 @@ static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
 
 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
 {
-	struct ipc_security_struct *isec = ipcp->security;
+	struct ipc_security_struct *isec = selinux_ipc(ipcp);
 	*secid = isec->sid;
 }
 
@@ -6173,7 +6018,7 @@ static int selinux_getprocattr(struct task_struct *p,
 	unsigned len;
 
 	rcu_read_lock();
-	__tsec = __task_cred(p)->security;
+	__tsec = selinux_cred(__task_cred(p));
 
 	if (current != p) {
 		error = avc_has_perm(&selinux_state,
@@ -6296,7 +6141,7 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 	   operation.  See selinux_bprm_set_creds for the execve
 	   checks and may_create for the file creation checks. The
 	   operation will then fail if the context is not permitted. */
-	tsec = new->security;
+	tsec = selinux_cred(new);
 	if (!strcmp(name, "exec")) {
 		tsec->exec_sid = sid;
 	} else if (!strcmp(name, "fscreate")) {
@@ -6380,7 +6225,7 @@ static void selinux_release_secctx(char *secdata, u32 seclen)
 
 static void selinux_inode_invalidate_secctx(struct inode *inode)
 {
-	struct inode_security_struct *isec = inode->i_security;
+	struct inode_security_struct *isec = selinux_inode(inode);
 
 	spin_lock(&isec->lock);
 	isec->initialized = LABEL_INVALID;
@@ -6425,7 +6270,7 @@ static int selinux_key_alloc(struct key *k, const struct cred *cred,
 	if (!ksec)
 		return -ENOMEM;
 
-	tsec = cred->security;
+	tsec = selinux_cred(cred);
 	if (tsec->keycreate_sid)
 		ksec->sid = tsec->keycreate_sid;
 	else
@@ -6688,6 +6533,14 @@ static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
 }
 #endif
 
+struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
+	.lbs_cred = sizeof(struct task_security_struct),
+	.lbs_file = sizeof(struct file_security_struct),
+	.lbs_inode = sizeof(struct inode_security_struct),
+	.lbs_ipc = sizeof(struct ipc_security_struct),
+	.lbs_msg_msg = sizeof(struct msg_security_struct),
+};
+
 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
 	LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
@@ -6757,7 +6610,6 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
 
 	LSM_HOOK_INIT(file_permission, selinux_file_permission),
 	LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
-	LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
 	LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
 	LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
 	LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
@@ -6771,8 +6623,6 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(file_open, selinux_file_open),
 
 	LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
-	LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
-	LSM_HOOK_INIT(cred_free, selinux_cred_free),
 	LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
 	LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
 	LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
@@ -6800,24 +6650,20 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
 
 	LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
-	LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
 
 	LSM_HOOK_INIT(msg_queue_alloc_security,
 			selinux_msg_queue_alloc_security),
-	LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
 	LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
 	LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
 	LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
 	LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
 
 	LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
-	LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
 	LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
 	LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
 	LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
 
 	LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
-	LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
 	LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
 	LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
 	LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
@@ -6928,16 +6774,6 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
 
 static __init int selinux_init(void)
 {
-	if (!security_module_enable("selinux")) {
-		selinux_enabled = 0;
-		return 0;
-	}
-
-	if (!selinux_enabled) {
-		pr_info("SELinux:  Disabled at boot.\n");
-		return 0;
-	}
-
 	pr_info("SELinux:  Initializing.\n");
 
 	memset(&selinux_state, 0, sizeof(selinux_state));
@@ -6951,12 +6787,6 @@ static __init int selinux_init(void)
 
 	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
 
-	sel_inode_cache = kmem_cache_create("selinux_inode_security",
-					    sizeof(struct inode_security_struct),
-					    0, SLAB_PANIC, NULL);
-	file_security_cache = kmem_cache_create("selinux_file_security",
-					    sizeof(struct file_security_struct),
-					    0, SLAB_PANIC, NULL);
 	avc_init();
 
 	avtab_cache_init();
@@ -6999,6 +6829,9 @@ void selinux_complete_init(void)
    all processes and objects when they are created. */
 DEFINE_LSM(selinux) = {
 	.name = "selinux",
+	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
+	.enabled = &selinux_enabled,
+	.blobs = &selinux_blob_sizes,
 	.init = selinux_init,
 };