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.

4 files changed, 157 insertions, 225 deletions

diff --git a/security/smack/smack.h b/security/smack/smack.h
index f7db791fb566..9c7c95a5c497 100644
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -24,6 +24,7 @@
 #include <linux/list.h>
 #include <linux/rculist.h>
 #include <linux/lsm_audit.h>
+#include <linux/msg.h>
 
 /*
  * Use IPv6 port labeling if IPv6 is enabled and secmarks
@@ -336,6 +337,7 @@ extern struct smack_known *smack_syslog_label;
 extern struct smack_known *smack_unconfined;
 #endif
 extern int smack_ptrace_rule;
+extern struct lsm_blob_sizes smack_blob_sizes;
 
 extern struct smack_known smack_known_floor;
 extern struct smack_known smack_known_hat;
@@ -356,12 +358,38 @@ extern struct list_head smack_onlycap_list;
 #define SMACK_HASH_SLOTS 16
 extern struct hlist_head smack_known_hash[SMACK_HASH_SLOTS];
 
+static inline struct task_smack *smack_cred(const struct cred *cred)
+{
+	return cred->security + smack_blob_sizes.lbs_cred;
+}
+
+static inline struct smack_known **smack_file(const struct file *file)
+{
+	return (struct smack_known **)(file->f_security +
+				       smack_blob_sizes.lbs_file);
+}
+
+static inline struct inode_smack *smack_inode(const struct inode *inode)
+{
+	return inode->i_security + smack_blob_sizes.lbs_inode;
+}
+
+static inline struct smack_known **smack_msg_msg(const struct msg_msg *msg)
+{
+	return msg->security + smack_blob_sizes.lbs_msg_msg;
+}
+
+static inline struct smack_known **smack_ipc(const struct kern_ipc_perm *ipc)
+{
+	return ipc->security + smack_blob_sizes.lbs_ipc;
+}
+
 /*
  * Is the directory transmuting?
  */
 static inline int smk_inode_transmutable(const struct inode *isp)
 {
-	struct inode_smack *sip = isp->i_security;
+	struct inode_smack *sip = smack_inode(isp);
 	return (sip->smk_flags & SMK_INODE_TRANSMUTE) != 0;
 }
 
@@ -370,7 +398,7 @@ static inline int smk_inode_transmutable(const struct inode *isp)
  */
 static inline struct smack_known *smk_of_inode(const struct inode *isp)
 {
-	struct inode_smack *sip = isp->i_security;
+	struct inode_smack *sip = smack_inode(isp);
 	return sip->smk_inode;
 }
 
@@ -382,13 +410,19 @@ static inline struct smack_known *smk_of_task(const struct task_smack *tsp)
 	return tsp->smk_task;
 }
 
-static inline struct smack_known *smk_of_task_struct(const struct task_struct *t)
+static inline struct smack_known *smk_of_task_struct(
+						const struct task_struct *t)
 {
 	struct smack_known *skp;
+	const struct cred *cred;
 
 	rcu_read_lock();
-	skp = smk_of_task(__task_cred(t)->security);
+
+	cred = __task_cred(t);
+	skp = smk_of_task(smack_cred(cred));
+
 	rcu_read_unlock();
+
 	return skp;
 }
 
@@ -405,7 +439,7 @@ static inline struct smack_known *smk_of_forked(const struct task_smack *tsp)
  */
 static inline struct smack_known *smk_of_current(void)
 {
-	return smk_of_task(current_security());
+	return smk_of_task(smack_cred(current_cred()));
 }
 
 /*
diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c
index 9a4c0ad46518..489d49a20b47 100644
--- a/security/smack/smack_access.c
+++ b/security/smack/smack_access.c
@@ -275,7 +275,7 @@ out_audit:
 int smk_curacc(struct smack_known *obj_known,
 	       u32 mode, struct smk_audit_info *a)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 
 	return smk_tskacc(tsp, obj_known, mode, a);
 }
@@ -635,7 +635,7 @@ DEFINE_MUTEX(smack_onlycap_lock);
  */
 bool smack_privileged_cred(int cap, const struct cred *cred)
 {
-	struct task_smack *tsp = cred->security;
+	struct task_smack *tsp = smack_cred(cred);
 	struct smack_known *skp = tsp->smk_task;
 	struct smack_known_list_elem *sklep;
 	int rc;
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 430d4f35e55c..0b848b1f6366 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -139,7 +139,7 @@ static int smk_bu_note(char *note, struct smack_known *sskp,
 static int smk_bu_current(char *note, struct smack_known *oskp,
 			  int mode, int rc)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 	char acc[SMK_NUM_ACCESS_TYPE + 1];
 
 	if (rc <= 0)
@@ -160,7 +160,7 @@ static int smk_bu_current(char *note, struct smack_known *oskp,
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
 static int smk_bu_task(struct task_struct *otp, int mode, int rc)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 	struct smack_known *smk_task = smk_of_task_struct(otp);
 	char acc[SMK_NUM_ACCESS_TYPE + 1];
 
@@ -182,8 +182,8 @@ static int smk_bu_task(struct task_struct *otp, int mode, int rc)
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
 static int smk_bu_inode(struct inode *inode, int mode, int rc)
 {
-	struct task_smack *tsp = current_security();
-	struct inode_smack *isp = inode->i_security;
+	struct task_smack *tsp = smack_cred(current_cred());
+	struct inode_smack *isp = smack_inode(inode);
 	char acc[SMK_NUM_ACCESS_TYPE + 1];
 
 	if (isp->smk_flags & SMK_INODE_IMPURE)
@@ -212,10 +212,10 @@ static int smk_bu_inode(struct inode *inode, int mode, int rc)
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
 static int smk_bu_file(struct file *file, int mode, int rc)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 	struct smack_known *sskp = tsp->smk_task;
 	struct inode *inode = file_inode(file);
-	struct inode_smack *isp = inode->i_security;
+	struct inode_smack *isp = smack_inode(inode);
 	char acc[SMK_NUM_ACCESS_TYPE + 1];
 
 	if (isp->smk_flags & SMK_INODE_IMPURE)
@@ -242,10 +242,10 @@ static int smk_bu_file(struct file *file, int mode, int rc)
 static int smk_bu_credfile(const struct cred *cred, struct file *file,
 				int mode, int rc)
 {
-	struct task_smack *tsp = cred->security;
+	struct task_smack *tsp = smack_cred(cred);
 	struct smack_known *sskp = tsp->smk_task;
 	struct inode *inode = file_inode(file);
-	struct inode_smack *isp = inode->i_security;
+	struct inode_smack *isp = smack_inode(inode);
 	char acc[SMK_NUM_ACCESS_TYPE + 1];
 
 	if (isp->smk_flags & SMK_INODE_IMPURE)
@@ -305,50 +305,35 @@ static struct smack_known *smk_fetch(const char *name, struct inode *ip,
 }
 
 /**
- * new_inode_smack - allocate an inode security blob
+ * init_inode_smack - initialize an inode security blob
+ * @isp: the blob to initialize
  * @skp: a pointer to the Smack label entry to use in the blob
  *
- * Returns the new blob or NULL if there's no memory available
  */
-static struct inode_smack *new_inode_smack(struct smack_known *skp)
+static void init_inode_smack(struct inode *inode, struct smack_known *skp)
 {
-	struct inode_smack *isp;
-
-	isp = kmem_cache_zalloc(smack_inode_cache, GFP_NOFS);
-	if (isp == NULL)
-		return NULL;
+	struct inode_smack *isp = smack_inode(inode);
 
 	isp->smk_inode = skp;
 	isp->smk_flags = 0;
 	mutex_init(&isp->smk_lock);
-
-	return isp;
 }
 
 /**
- * new_task_smack - allocate a task security blob
+ * init_task_smack - initialize a task security blob
+ * @tsp: blob to initialize
  * @task: a pointer to the Smack label for the running task
  * @forked: a pointer to the Smack label for the forked task
- * @gfp: type of the memory for the allocation
  *
- * Returns the new blob or NULL if there's no memory available
  */
-static struct task_smack *new_task_smack(struct smack_known *task,
-					struct smack_known *forked, gfp_t gfp)
+static void init_task_smack(struct task_smack *tsp, struct smack_known *task,
+					struct smack_known *forked)
 {
-	struct task_smack *tsp;
-
-	tsp = kzalloc(sizeof(struct task_smack), gfp);
-	if (tsp == NULL)
-		return NULL;
-
 	tsp->smk_task = task;
 	tsp->smk_forked = forked;
 	INIT_LIST_HEAD(&tsp->smk_rules);
 	INIT_LIST_HEAD(&tsp->smk_relabel);
 	mutex_init(&tsp->smk_rules_lock);
-
-	return tsp;
 }
 
 /**
@@ -448,7 +433,7 @@ static int smk_ptrace_rule_check(struct task_struct *tracer,
 
 	rcu_read_lock();
 	tracercred = __task_cred(tracer);
-	tsp = tracercred->security;
+	tsp = smack_cred(tracercred);
 	tracer_known = smk_of_task(tsp);
 
 	if ((mode & PTRACE_MODE_ATTACH) &&
@@ -515,7 +500,7 @@ static int smack_ptrace_traceme(struct task_struct *ptp)
 	int rc;
 	struct smack_known *skp;
 
-	skp = smk_of_task(current_security());
+	skp = smk_of_task(smack_cred(current_cred()));
 
 	rc = smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__);
 	return rc;
@@ -718,6 +703,13 @@ static int smack_set_mnt_opts(struct super_block *sb,
 	if (sp->smk_flags & SMK_SB_INITIALIZED)
 		return 0;
 
+	if (inode->i_security == NULL) {
+		int rc = lsm_inode_alloc(inode);
+
+		if (rc)
+			return rc;
+	}
+
 	if (!smack_privileged(CAP_MAC_ADMIN)) {
 		/*
 		 * Unprivileged mounts don't get to specify Smack values.
@@ -782,17 +774,12 @@ static int smack_set_mnt_opts(struct super_block *sb,
 	/*
 	 * Initialize the root inode.
 	 */
-	isp = inode->i_security;
-	if (isp == NULL) {
-		isp = new_inode_smack(sp->smk_root);
-		if (isp == NULL)
-			return -ENOMEM;
-		inode->i_security = isp;
-	} else
-		isp->smk_inode = sp->smk_root;
+	init_inode_smack(inode, sp->smk_root);
 
-	if (transmute)
+	if (transmute) {
+		isp = smack_inode(inode);
 		isp->smk_flags |= SMK_INODE_TRANSMUTE;
+	}
 
 	return 0;
 }
@@ -831,7 +818,7 @@ static int smack_sb_statfs(struct dentry *dentry)
 static int smack_bprm_set_creds(struct linux_binprm *bprm)
 {
 	struct inode *inode = file_inode(bprm->file);
-	struct task_smack *bsp = bprm->cred->security;
+	struct task_smack *bsp = smack_cred(bprm->cred);
 	struct inode_smack *isp;
 	struct superblock_smack *sbsp;
 	int rc;
@@ -839,7 +826,7 @@ static int smack_bprm_set_creds(struct linux_binprm *bprm)
 	if (bprm->called_set_creds)
 		return 0;
 
-	isp = inode->i_security;
+	isp = smack_inode(inode);
 	if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
 		return 0;
 
@@ -890,49 +877,11 @@ static int smack_inode_alloc_security(struct inode *inode)
 {
 	struct smack_known *skp = smk_of_current();
 
-	inode->i_security = new_inode_smack(skp);
-	if (inode->i_security == NULL)
-		return -ENOMEM;
+	init_inode_smack(inode, skp);
 	return 0;
 }
 
 /**
- * smack_inode_free_rcu - Free inode_smack blob from cache
- * @head: the rcu_head for getting inode_smack pointer
- *
- *  Call back function called from call_rcu() to free
- *  the i_security blob pointer in inode
- */
-static void smack_inode_free_rcu(struct rcu_head *head)
-{
-	struct inode_smack *issp;
-
-	issp = container_of(head, struct inode_smack, smk_rcu);
-	kmem_cache_free(smack_inode_cache, issp);
-}
-
-/**
- * smack_inode_free_security - free an inode blob using call_rcu()
- * @inode: the inode with a blob
- *
- * Clears the blob pointer in inode using RCU
- */
-static void smack_inode_free_security(struct inode *inode)
-{
-	struct inode_smack *issp = inode->i_security;
-
-	/*
-	 * The inode may still be referenced in a path walk and
-	 * a call to smack_inode_permission() can be made
-	 * after smack_inode_free_security() is called.
-	 * To avoid race condition 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(&issp->smk_rcu, smack_inode_free_rcu);
-}
-
-/**
  * smack_inode_init_security - copy out the smack from an inode
  * @inode: the newly created inode
  * @dir: containing directory object
@@ -947,7 +896,7 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir,
 				     const struct qstr *qstr, const char **name,
 				     void **value, size_t *len)
 {
-	struct inode_smack *issp = inode->i_security;
+	struct inode_smack *issp = smack_inode(inode);
 	struct smack_known *skp = smk_of_current();
 	struct smack_known *isp = smk_of_inode(inode);
 	struct smack_known *dsp = smk_of_inode(dir);
@@ -1285,7 +1234,7 @@ static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
 				      const void *value, size_t size, int flags)
 {
 	struct smack_known *skp;
-	struct inode_smack *isp = d_backing_inode(dentry)->i_security;
+	struct inode_smack *isp = smack_inode(d_backing_inode(dentry));
 
 	if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
 		isp->smk_flags |= SMK_INODE_TRANSMUTE;
@@ -1366,7 +1315,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
 	if (rc != 0)
 		return rc;
 
-	isp = d_backing_inode(dentry)->i_security;
+	isp = smack_inode(d_backing_inode(dentry));
 	/*
 	 * Don't do anything special for these.
 	 *	XATTR_NAME_SMACKIPIN
@@ -1498,25 +1447,13 @@ static void smack_inode_getsecid(struct inode *inode, u32 *secid)
  */
 static int smack_file_alloc_security(struct file *file)
 {
-	struct smack_known *skp = smk_of_current();
+	struct smack_known **blob = smack_file(file);
 
-	file->f_security = skp;
+	*blob = smk_of_current();
 	return 0;
 }
 
 /**
- * smack_file_free_security - clear a file security blob
- * @file: the object
- *
- * The security blob for a file is a pointer to the master
- * label list, so no memory is freed.
- */
-static void smack_file_free_security(struct file *file)
-{
-	file->f_security = NULL;
-}
-
-/**
  * smack_file_ioctl - Smack check on ioctls
  * @file: the object
  * @cmd: what to do
@@ -1653,7 +1590,7 @@ static int smack_mmap_file(struct file *file,
 	if (unlikely(IS_PRIVATE(file_inode(file))))
 		return 0;
 
-	isp = file_inode(file)->i_security;
+	isp = smack_inode(file_inode(file));
 	if (isp->smk_mmap == NULL)
 		return 0;
 	sbsp = file_inode(file)->i_sb->s_security;
@@ -1662,7 +1599,7 @@ static int smack_mmap_file(struct file *file,
 		return -EACCES;
 	mkp = isp->smk_mmap;
 
-	tsp = current_security();
+	tsp = smack_cred(current_cred());
 	skp = smk_of_current();
 	rc = 0;
 
@@ -1740,7 +1677,9 @@ static int smack_mmap_file(struct file *file,
  */
 static void smack_file_set_fowner(struct file *file)
 {
-	file->f_security = smk_of_current();
+	struct smack_known **blob = smack_file(file);
+
+	*blob = smk_of_current();
 }
 
 /**
@@ -1757,8 +1696,9 @@ static void smack_file_set_fowner(struct file *file)
 static int smack_file_send_sigiotask(struct task_struct *tsk,
 				     struct fown_struct *fown, int signum)
 {
+	struct smack_known **blob;
 	struct smack_known *skp;
-	struct smack_known *tkp = smk_of_task(tsk->cred->security);
+	struct smack_known *tkp = smk_of_task(smack_cred(tsk->cred));
 	const struct cred *tcred;
 	struct file *file;
 	int rc;
@@ -1770,7 +1710,8 @@ static int smack_file_send_sigiotask(struct task_struct *tsk,
 	file = container_of(fown, struct file, f_owner);
 
 	/* we don't log here as rc can be overriden */
-	skp = file->f_security;
+	blob = smack_file(file);
+	skp = *blob;
 	rc = smk_access(skp, tkp, MAY_DELIVER, NULL);
 	rc = smk_bu_note("sigiotask", skp, tkp, MAY_DELIVER, rc);
 
@@ -1811,7 +1752,7 @@ static int smack_file_receive(struct file *file)
 	if (inode->i_sb->s_magic == SOCKFS_MAGIC) {
 		sock = SOCKET_I(inode);
 		ssp = sock->sk->sk_security;
-		tsp = current_security();
+		tsp = smack_cred(current_cred());
 		/*
 		 * If the receiving process can't write to the
 		 * passed socket or if the passed socket can't
@@ -1853,7 +1794,7 @@ static int smack_file_receive(struct file *file)
  */
 static int smack_file_open(struct file *file)
 {
-	struct task_smack *tsp = file->f_cred->security;
+	struct task_smack *tsp = smack_cred(file->f_cred);
 	struct inode *inode = file_inode(file);
 	struct smk_audit_info ad;
 	int rc;
@@ -1881,14 +1822,7 @@ static int smack_file_open(struct file *file)
  */
 static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
 {
-	struct task_smack *tsp;
-
-	tsp = new_task_smack(NULL, NULL, gfp);
-	if (tsp == NULL)
-		return -ENOMEM;
-
-	cred->security = tsp;
-
+	init_task_smack(smack_cred(cred), NULL, NULL);
 	return 0;
 }
 
@@ -1900,15 +1834,11 @@ static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
  */
 static void smack_cred_free(struct cred *cred)
 {
-	struct task_smack *tsp = cred->security;
+	struct task_smack *tsp = smack_cred(cred);
 	struct smack_rule *rp;
 	struct list_head *l;
 	struct list_head *n;
 
-	if (tsp == NULL)
-		return;
-	cred->security = NULL;
-
 	smk_destroy_label_list(&tsp->smk_relabel);
 
 	list_for_each_safe(l, n, &tsp->smk_rules) {
@@ -1916,7 +1846,6 @@ static void smack_cred_free(struct cred *cred)
 		list_del(&rp->list);
 		kfree(rp);
 	}
-	kfree(tsp);
 }
 
 /**
@@ -1930,15 +1859,11 @@ static void smack_cred_free(struct cred *cred)
 static int smack_cred_prepare(struct cred *new, const struct cred *old,
 			      gfp_t gfp)
 {
-	struct task_smack *old_tsp = old->security;
-	struct task_smack *new_tsp;
+	struct task_smack *old_tsp = smack_cred(old);
+	struct task_smack *new_tsp = smack_cred(new);
 	int rc;
 
-	new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
-	if (new_tsp == NULL)
-		return -ENOMEM;
-
-	new->security = new_tsp;
+	init_task_smack(new_tsp, old_tsp->smk_task, old_tsp->smk_task);
 
 	rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
 	if (rc != 0)
@@ -1946,10 +1871,7 @@ static int smack_cred_prepare(struct cred *new, const struct cred *old,
 
 	rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel,
 				gfp);
-	if (rc != 0)
-		return rc;
-
-	return 0;
+	return rc;
 }
 
 /**
@@ -1961,15 +1883,14 @@ static int smack_cred_prepare(struct cred *new, const struct cred *old,
  */
 static void smack_cred_transfer(struct cred *new, const struct cred *old)
 {
-	struct task_smack *old_tsp = old->security;
-	struct task_smack *new_tsp = new->security;
+	struct task_smack *old_tsp = smack_cred(old);
+	struct task_smack *new_tsp = smack_cred(new);
 
 	new_tsp->smk_task = old_tsp->smk_task;
 	new_tsp->smk_forked = old_tsp->smk_task;
 	mutex_init(&new_tsp->smk_rules_lock);
 	INIT_LIST_HEAD(&new_tsp->smk_rules);
 
-
 	/* cbs copy rule list */
 }
 
@@ -1980,12 +1901,12 @@ static void smack_cred_transfer(struct cred *new, const struct cred *old)
  *
  * Sets the secid to contain a u32 version of the smack label.
  */
-static void smack_cred_getsecid(const struct cred *c, u32 *secid)
+static void smack_cred_getsecid(const struct cred *cred, u32 *secid)
 {
 	struct smack_known *skp;
 
 	rcu_read_lock();
-	skp = smk_of_task(c->security);
+	skp = smk_of_task(smack_cred(cred));
 	*secid = skp->smk_secid;
 	rcu_read_unlock();
 }
@@ -1999,7 +1920,7 @@ static void smack_cred_getsecid(const struct cred *c, u32 *secid)
  */
 static int smack_kernel_act_as(struct cred *new, u32 secid)
 {
-	struct task_smack *new_tsp = new->security;
+	struct task_smack *new_tsp = smack_cred(new);
 
 	new_tsp->smk_task = smack_from_secid(secid);
 	return 0;
@@ -2016,8 +1937,8 @@ static int smack_kernel_act_as(struct cred *new, u32 secid)
 static int smack_kernel_create_files_as(struct cred *new,
 					struct inode *inode)
 {
-	struct inode_smack *isp = inode->i_security;
-	struct task_smack *tsp = new->security;
+	struct inode_smack *isp = smack_inode(inode);
+	struct task_smack *tsp = smack_cred(new);
 
 	tsp->smk_forked = isp->smk_inode;
 	tsp->smk_task = tsp->smk_forked;
@@ -2201,7 +2122,7 @@ static int smack_task_kill(struct task_struct *p, struct kernel_siginfo *info,
 	 * specific behavior. This is not clean. For one thing
 	 * we can't take privilege into account.
 	 */
-	skp = smk_of_task(cred->security);
+	skp = smk_of_task(smack_cred(cred));
 	rc = smk_access(skp, tkp, MAY_DELIVER, &ad);
 	rc = smk_bu_note("USB signal", skp, tkp, MAY_DELIVER, rc);
 	return rc;
@@ -2216,7 +2137,7 @@ static int smack_task_kill(struct task_struct *p, struct kernel_siginfo *info,
  */
 static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
 {
-	struct inode_smack *isp = inode->i_security;
+	struct inode_smack *isp = smack_inode(inode);
 	struct smack_known *skp = smk_of_task_struct(p);
 
 	isp->smk_inode = skp;
@@ -2679,7 +2600,7 @@ static int smack_inode_setsecurity(struct inode *inode, const char *name,
 				   const void *value, size_t size, int flags)
 {
 	struct smack_known *skp;
-	struct inode_smack *nsp = inode->i_security;
+	struct inode_smack *nsp = smack_inode(inode);
 	struct socket_smack *ssp;
 	struct socket *sock;
 	int rc = 0;
@@ -2888,24 +2809,13 @@ static int smack_flags_to_may(int flags)
  */
 static int smack_msg_msg_alloc_security(struct msg_msg *msg)
 {
-	struct smack_known *skp = smk_of_current();
+	struct smack_known **blob = smack_msg_msg(msg);
 
-	msg->security = skp;
+	*blob = smk_of_current();
 	return 0;
 }
 
 /**
- * smack_msg_msg_free_security - Clear the security blob for msg_msg
- * @msg: the object
- *
- * Clears the blob pointer
- */
-static void smack_msg_msg_free_security(struct msg_msg *msg)
-{
-	msg->security = NULL;
-}
-
-/**
  * smack_of_ipc - the smack pointer for the ipc
  * @isp: the object
  *
@@ -2913,7 +2823,9 @@ static void smack_msg_msg_free_security(struct msg_msg *msg)
  */
 static struct smack_known *smack_of_ipc(struct kern_ipc_perm *isp)
 {
-	return (struct smack_known *)isp->security;
+	struct smack_known **blob = smack_ipc(isp);
+
+	return *blob;
 }
 
 /**
@@ -2924,24 +2836,13 @@ static struct smack_known *smack_of_ipc(struct kern_ipc_perm *isp)
  */
 static int smack_ipc_alloc_security(struct kern_ipc_perm *isp)
 {
-	struct smack_known *skp = smk_of_current();
+	struct smack_known **blob = smack_ipc(isp);
 
-	isp->security = skp;
+	*blob = smk_of_current();
 	return 0;
 }
 
 /**
- * smack_ipc_free_security - Clear the security blob for ipc
- * @isp: the object
- *
- * Clears the blob pointer
- */
-static void smack_ipc_free_security(struct kern_ipc_perm *isp)
-{
-	isp->security = NULL;
-}
-
-/**
  * smk_curacc_shm : check if current has access on shm
  * @isp : the object
  * @access : access requested
@@ -3238,7 +3139,8 @@ static int smack_msg_queue_msgrcv(struct kern_ipc_perm *isp, struct msg_msg *msg
  */
 static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
 {
-	struct smack_known *iskp = ipp->security;
+	struct smack_known **blob = smack_ipc(ipp);
+	struct smack_known *iskp = *blob;
 	int may = smack_flags_to_may(flag);
 	struct smk_audit_info ad;
 	int rc;
@@ -3259,7 +3161,8 @@ static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
  */
 static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
 {
-	struct smack_known *iskp = ipp->security;
+	struct smack_known **blob = smack_ipc(ipp);
+	struct smack_known *iskp = *blob;
 
 	*secid = iskp->smk_secid;
 }
@@ -3287,7 +3190,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
 	if (inode == NULL)
 		return;
 
-	isp = inode->i_security;
+	isp = smack_inode(inode);
 
 	mutex_lock(&isp->smk_lock);
 	/*
@@ -3528,7 +3431,7 @@ static int smack_getprocattr(struct task_struct *p, char *name, char **value)
  */
 static int smack_setprocattr(const char *name, void *value, size_t size)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 	struct cred *new;
 	struct smack_known *skp;
 	struct smack_known_list_elem *sklep;
@@ -3569,7 +3472,7 @@ static int smack_setprocattr(const char *name, void *value, size_t size)
 	if (new == NULL)
 		return -ENOMEM;
 
-	tsp = new->security;
+	tsp = smack_cred(new);
 	tsp->smk_task = skp;
 	/*
 	 * process can change its label only once
@@ -4214,7 +4117,7 @@ static void smack_inet_csk_clone(struct sock *sk,
 static int smack_key_alloc(struct key *key, const struct cred *cred,
 			   unsigned long flags)
 {
-	struct smack_known *skp = smk_of_task(cred->security);
+	struct smack_known *skp = smk_of_task(smack_cred(cred));
 
 	key->security = skp;
 	return 0;
@@ -4245,7 +4148,7 @@ static int smack_key_permission(key_ref_t key_ref,
 {
 	struct key *keyp;
 	struct smk_audit_info ad;
-	struct smack_known *tkp = smk_of_task(cred->security);
+	struct smack_known *tkp = smk_of_task(smack_cred(cred));
 	int request = 0;
 	int rc;
 
@@ -4520,12 +4423,12 @@ static int smack_inode_copy_up(struct dentry *dentry, struct cred **new)
 			return -ENOMEM;
 	}
 
-	tsp = new_creds->security;
+	tsp = smack_cred(new_creds);
 
 	/*
 	 * Get label from overlay inode and set it in create_sid
 	 */
-	isp = d_inode(dentry->d_parent)->i_security;
+	isp = smack_inode(d_inode(dentry->d_parent));
 	skp = isp->smk_inode;
 	tsp->smk_task = skp;
 	*new = new_creds;
@@ -4548,8 +4451,8 @@ static int smack_dentry_create_files_as(struct dentry *dentry, int mode,
 					const struct cred *old,
 					struct cred *new)
 {
-	struct task_smack *otsp = old->security;
-	struct task_smack *ntsp = new->security;
+	struct task_smack *otsp = smack_cred(old);
+	struct task_smack *ntsp = smack_cred(new);
 	struct inode_smack *isp;
 	int may;
 
@@ -4562,7 +4465,7 @@ static int smack_dentry_create_files_as(struct dentry *dentry, int mode,
 	/*
 	 * the attribute of the containing directory
 	 */
-	isp = d_inode(dentry->d_parent)->i_security;
+	isp = smack_inode(d_inode(dentry->d_parent));
 
 	if (isp->smk_flags & SMK_INODE_TRANSMUTE) {
 		rcu_read_lock();
@@ -4582,6 +4485,14 @@ static int smack_dentry_create_files_as(struct dentry *dentry, int mode,
 	return 0;
 }
 
+struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = {
+	.lbs_cred = sizeof(struct task_smack),
+	.lbs_file = sizeof(struct smack_known *),
+	.lbs_inode = sizeof(struct inode_smack),
+	.lbs_ipc = sizeof(struct smack_known *),
+	.lbs_msg_msg = sizeof(struct smack_known *),
+};
+
 static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
 	LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
@@ -4597,7 +4508,6 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(bprm_set_creds, smack_bprm_set_creds),
 
 	LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_security),
-	LSM_HOOK_INIT(inode_free_security, smack_inode_free_security),
 	LSM_HOOK_INIT(inode_init_security, smack_inode_init_security),
 	LSM_HOOK_INIT(inode_link, smack_inode_link),
 	LSM_HOOK_INIT(inode_unlink, smack_inode_unlink),
@@ -4616,7 +4526,6 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(inode_getsecid, smack_inode_getsecid),
 
 	LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_security),
-	LSM_HOOK_INIT(file_free_security, smack_file_free_security),
 	LSM_HOOK_INIT(file_ioctl, smack_file_ioctl),
 	LSM_HOOK_INIT(file_lock, smack_file_lock),
 	LSM_HOOK_INIT(file_fcntl, smack_file_fcntl),
@@ -4652,23 +4561,19 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(ipc_getsecid, smack_ipc_getsecid),
 
 	LSM_HOOK_INIT(msg_msg_alloc_security, smack_msg_msg_alloc_security),
-	LSM_HOOK_INIT(msg_msg_free_security, smack_msg_msg_free_security),
 
 	LSM_HOOK_INIT(msg_queue_alloc_security, smack_ipc_alloc_security),
-	LSM_HOOK_INIT(msg_queue_free_security, smack_ipc_free_security),
 	LSM_HOOK_INIT(msg_queue_associate, smack_msg_queue_associate),
 	LSM_HOOK_INIT(msg_queue_msgctl, smack_msg_queue_msgctl),
 	LSM_HOOK_INIT(msg_queue_msgsnd, smack_msg_queue_msgsnd),
 	LSM_HOOK_INIT(msg_queue_msgrcv, smack_msg_queue_msgrcv),
 
 	LSM_HOOK_INIT(shm_alloc_security, smack_ipc_alloc_security),
-	LSM_HOOK_INIT(shm_free_security, smack_ipc_free_security),
 	LSM_HOOK_INIT(shm_associate, smack_shm_associate),
 	LSM_HOOK_INIT(shm_shmctl, smack_shm_shmctl),
 	LSM_HOOK_INIT(shm_shmat, smack_shm_shmat),
 
 	LSM_HOOK_INIT(sem_alloc_security, smack_ipc_alloc_security),
-	LSM_HOOK_INIT(sem_free_security, smack_ipc_free_security),
 	LSM_HOOK_INIT(sem_associate, smack_sem_associate),
 	LSM_HOOK_INIT(sem_semctl, smack_sem_semctl),
 	LSM_HOOK_INIT(sem_semop, smack_sem_semop),
@@ -4759,23 +4664,25 @@ static __init void init_smack_known_list(void)
  */
 static __init int smack_init(void)
 {
-	struct cred *cred;
+	struct cred *cred = (struct cred *) current->cred;
 	struct task_smack *tsp;
 
-	if (!security_module_enable("smack"))
-		return 0;
-
 	smack_inode_cache = KMEM_CACHE(inode_smack, 0);
 	if (!smack_inode_cache)
 		return -ENOMEM;
 
-	tsp = new_task_smack(&smack_known_floor, &smack_known_floor,
-				GFP_KERNEL);
-	if (tsp == NULL) {
-		kmem_cache_destroy(smack_inode_cache);
-		return -ENOMEM;
-	}
+	lsm_early_cred(cred);
+
+	/*
+	 * Set the security state for the initial task.
+	 */
+	tsp = smack_cred(cred);
+	init_task_smack(tsp, &smack_known_floor, &smack_known_floor);
 
+	/*
+	 * Register with LSM
+	 */
+	security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack");
 	smack_enabled = 1;
 
 	pr_info("Smack:  Initializing.\n");
@@ -4789,20 +4696,9 @@ static __init int smack_init(void)
 	pr_info("Smack:  IPv6 Netfilter enabled.\n");
 #endif
 
-	/*
-	 * Set the security state for the initial task.
-	 */
-	cred = (struct cred *) current->cred;
-	cred->security = tsp;
-
 	/* initialize the smack_known_list */
 	init_smack_known_list();
 
-	/*
-	 * Register with LSM
-	 */
-	security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack");
-
 	return 0;
 }
 
@@ -4812,5 +4708,7 @@ static __init int smack_init(void)
  */
 DEFINE_LSM(smack) = {
 	.name = "smack",
+	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
+	.blobs = &smack_blob_sizes,
 	.init = smack_init,
 };
diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
index 06b517075ec0..faf2ea3968b3 100644
--- a/security/smack/smackfs.c
+++ b/security/smack/smackfs.c
@@ -2208,14 +2208,14 @@ static const struct file_operations smk_logging_ops = {
 
 static void *load_self_seq_start(struct seq_file *s, loff_t *pos)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 
 	return smk_seq_start(s, pos, &tsp->smk_rules);
 }
 
 static void *load_self_seq_next(struct seq_file *s, void *v, loff_t *pos)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 
 	return smk_seq_next(s, v, pos, &tsp->smk_rules);
 }
@@ -2262,7 +2262,7 @@ static int smk_open_load_self(struct inode *inode, struct file *file)
 static ssize_t smk_write_load_self(struct file *file, const char __user *buf,
 			      size_t count, loff_t *ppos)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 
 	return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules,
 				    &tsp->smk_rules_lock, SMK_FIXED24_FMT);
@@ -2414,14 +2414,14 @@ static const struct file_operations smk_load2_ops = {
 
 static void *load_self2_seq_start(struct seq_file *s, loff_t *pos)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 
 	return smk_seq_start(s, pos, &tsp->smk_rules);
 }
 
 static void *load_self2_seq_next(struct seq_file *s, void *v, loff_t *pos)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 
 	return smk_seq_next(s, v, pos, &tsp->smk_rules);
 }
@@ -2467,7 +2467,7 @@ static int smk_open_load_self2(struct inode *inode, struct file *file)
 static ssize_t smk_write_load_self2(struct file *file, const char __user *buf,
 			      size_t count, loff_t *ppos)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 
 	return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules,
 				    &tsp->smk_rules_lock, SMK_LONG_FMT);
@@ -2681,14 +2681,14 @@ static const struct file_operations smk_syslog_ops = {
 
 static void *relabel_self_seq_start(struct seq_file *s, loff_t *pos)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 
 	return smk_seq_start(s, pos, &tsp->smk_relabel);
 }
 
 static void *relabel_self_seq_next(struct seq_file *s, void *v, loff_t *pos)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 
 	return smk_seq_next(s, v, pos, &tsp->smk_relabel);
 }
@@ -2736,7 +2736,7 @@ static int smk_open_relabel_self(struct inode *inode, struct file *file)
 static ssize_t smk_write_relabel_self(struct file *file, const char __user *buf,
 				size_t count, loff_t *ppos)
 {
-	struct task_smack *tsp = current_security();
+	struct task_smack *tsp = smack_cred(current_cred());
 	char *data;
 	int rc;
 	LIST_HEAD(list_tmp);