1 files changed, 142 insertions, 280 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 4ba83de5fa80..c5363f0c67ef 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -81,7 +81,6 @@
 #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>
@@ -123,9 +122,8 @@ __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;
@@ -134,8 +132,6 @@ 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 =
@@ -151,9 +147,6 @@ 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
  *
@@ -216,12 +209,8 @@ 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");
-
+        tsec = selinux_cred(cred);
         tsec->osid = tsec->sid = SECINITSID_KERNEL;
-        cred->security = tsec;
 }
 
 /*
@@ -231,7 +220,7 @@ 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;
 }
 
@@ -252,13 +241,9 @@ 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;
@@ -266,7 +251,6 @@ 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;
 }
@@ -283,7 +267,7 @@ 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);
 
@@ -304,7 +288,7 @@ 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)
@@ -314,7 +298,7 @@ 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);
 }
 
 /*
@@ -323,14 +307,14 @@ 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);
 }
 
 /*
@@ -341,22 +325,17 @@ 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
@@ -372,42 +351,19 @@ 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;
@@ -503,7 +459,7 @@ 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,
@@ -522,7 +478,7 @@ 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,
@@ -536,16 +492,10 @@ static int may_context_mount_inode_relabel(u32 sid,
         return rc;
 }
 
-static int selinux_is_sblabel_mnt(struct super_block *sb)
+static int selinux_is_genfs_special_handling(struct super_block *sb)
 {
-        struct superblock_security_struct *sbsec = sb->s_security;
-
-        return sbsec->behavior == SECURITY_FS_USE_XATTR ||
-                sbsec->behavior == SECURITY_FS_USE_TRANS ||
-                sbsec->behavior == SECURITY_FS_USE_TASK ||
-                sbsec->behavior == SECURITY_FS_USE_NATIVE ||
-                /* Special handling. Genfs but also in-core setxattr handler */
-                !strcmp(sb->s_type->name, "sysfs") ||
+        /* Special handling. Genfs but also in-core setxattr handler */
+        return  !strcmp(sb->s_type->name, "sysfs") ||
                 !strcmp(sb->s_type->name, "pstore") ||
                 !strcmp(sb->s_type->name, "debugfs") ||
                 !strcmp(sb->s_type->name, "tracefs") ||
@@ -555,6 +505,34 @@ static int selinux_is_sblabel_mnt(struct super_block *sb)
                   !strcmp(sb->s_type->name, "cgroup2")));
 }
 
+static int selinux_is_sblabel_mnt(struct super_block *sb)
+{
+        struct superblock_security_struct *sbsec = sb->s_security;
+
+        /*
+         * IMPORTANT: Double-check logic in this function when adding a new
+         * SECURITY_FS_USE_* definition!
+         */
+        BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
+
+        switch (sbsec->behavior) {
+        case SECURITY_FS_USE_XATTR:
+        case SECURITY_FS_USE_TRANS:
+        case SECURITY_FS_USE_TASK:
+        case SECURITY_FS_USE_NATIVE:
+                return 1;
+
+        case SECURITY_FS_USE_GENFS:
+                return selinux_is_genfs_special_handling(sb);
+
+        /* Never allow relabeling on context mounts */
+        case SECURITY_FS_USE_MNTPOINT:
+        case SECURITY_FS_USE_NONE:
+        default:
+                return 0;
+        }
+}
+
 static int sb_finish_set_opts(struct super_block *sb)
 {
         struct superblock_security_struct *sbsec = sb->s_security;
@@ -1377,7 +1355,7 @@ 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;
@@ -1624,7 +1602,7 @@ static inline u32 signal_to_av(int sig)
 
 /* Check whether a task is allowed to use a capability. */
 static int cred_has_capability(const struct cred *cred,
-                               int cap, int audit, bool initns)
+                               int cap, unsigned int opts, bool initns)
 {
         struct common_audit_data ad;
         struct av_decision avd;
@@ -1651,7 +1629,7 @@ static int cred_has_capability(const struct cred *cred,
 
         rc = avc_has_perm_noaudit(&selinux_state,
                                   sid, sid, sclass, av, 0, &avd);
-        if (audit == SECURITY_CAP_AUDIT) {
+        if (!(opts & CAP_OPT_NOAUDIT)) {
                 int rc2 = avc_audit(&selinux_state,
                                     sid, sid, sclass, av, &avd, rc, &ad, 0);
                 if (rc2)
@@ -1677,7 +1655,7 @@ 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);
@@ -1743,7 +1721,7 @@ 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);
@@ -1809,7 +1787,7 @@ 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;
@@ -1831,7 +1809,7 @@ 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;
@@ -2087,7 +2065,7 @@ 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;
@@ -2171,9 +2149,9 @@ static int selinux_capset(struct cred *new, const struct cred *old,
  */
 
 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
-                           int cap, int audit)
+                           int cap, unsigned int opts)
 {
-        return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
+        return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
 }
 
 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
@@ -2247,7 +2225,7 @@ static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
         int rc, cap_sys_admin = 0;
 
         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
-                                 SECURITY_CAP_NOAUDIT, true);
+                                 CAP_OPT_NOAUDIT, true);
         if (rc == 0)
                 cap_sys_admin = 1;
 
@@ -2338,8 +2316,8 @@ 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. */
@@ -2503,7 +2481,7 @@ 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;
 
@@ -2546,7 +2524,7 @@ 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;
@@ -2853,7 +2831,7 @@ 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);
@@ -2873,14 +2851,14 @@ 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;
 }
@@ -2890,7 +2868,7 @@ 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;
@@ -2900,7 +2878,7 @@ 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);
@@ -2909,7 +2887,7 @@ 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;
@@ -2998,9 +2976,8 @@ static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
         if (IS_ERR(isec))
                 return PTR_ERR(isec);
 
-        return avc_has_perm_flags(&selinux_state,
-                                  sid, isec->sid, isec->sclass, FILE__READ, &ad,
-                                  rcu ? MAY_NOT_BLOCK : 0);
+        return avc_has_perm(&selinux_state,
+                            sid, isec->sid, isec->sclass, FILE__READ, &ad);
 }
 
 static noinline int audit_inode_permission(struct inode *inode,
@@ -3009,7 +2986,7 @@ 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;
@@ -3055,7 +3032,9 @@ static int selinux_inode_permission(struct inode *inode, int mask)
                 return PTR_ERR(isec);
 
         rc = avc_has_perm_noaudit(&selinux_state,
-                                  sid, isec->sid, isec->sclass, perms, 0, &avd);
+                                  sid, isec->sid, isec->sclass, perms,
+                                  (flags & MAY_NOT_BLOCK) ? AVC_NONBLOCKING : 0,
+                                  &avd);
         audited = avc_audit_required(perms, &avd, rc,
                                      from_access ? FILE__AUDIT_ACCESS : 0,
                                      &denied);
@@ -3104,11 +3083,11 @@ static int selinux_inode_getattr(const struct path *path)
 static bool has_cap_mac_admin(bool audit)
 {
         const struct cred *cred = current_cred();
-        int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT;
+        unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
 
-        if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit))
+        if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
                 return false;
-        if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true))
+        if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
                 return false;
         return true;
 }
@@ -3314,12 +3293,16 @@ static int selinux_inode_setsecurity(struct inode *inode, const char *name,
                                      const void *value, size_t size, int flags)
 {
         struct inode_security_struct *isec = inode_security_novalidate(inode);
+        struct superblock_security_struct *sbsec = inode->i_sb->s_security;
         u32 newsid;
         int rc;
 
         if (strcmp(name, XATTR_SELINUX_SUFFIX))
                 return -EOPNOTSUPP;
 
+        if (!(sbsec->flags & SBLABEL_MNT))
+                return -EOPNOTSUPP;
+
         if (!value || !size)
                 return -EACCES;
 
@@ -3362,7 +3345,7 @@ 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;
@@ -3403,7 +3386,7 @@ 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();
 
@@ -3425,11 +3408,6 @@ 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.
@@ -3438,7 +3416,7 @@ 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;
@@ -3508,7 +3486,7 @@ static int selinux_file_ioctl(struct file *file, unsigned int cmd,
         case KDSKBENT:
         case KDSKBSENT:
                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
-                                            SECURITY_CAP_AUDIT, true);
+                                            CAP_OPT_NONE, true);
                 break;
 
         /* default case assumes that the command will go
@@ -3690,7 +3668,7 @@ 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();
 }
 
@@ -3705,7 +3683,7 @@ 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 */
@@ -3729,7 +3707,7 @@ 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
@@ -3763,52 +3741,15 @@ 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;
-
-        tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
-        if (!tsec)
-                return -ENOMEM;
+        const struct task_security_struct *old_tsec = selinux_cred(old);
+        struct task_security_struct *tsec = selinux_cred(new);
 
-        new->security = tsec;
+        *tsec = *old_tsec;
         return 0;
 }
 
@@ -3817,8 +3758,8 @@ 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;
 }
@@ -3834,7 +3775,7 @@ 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;
 
@@ -3859,7 +3800,7 @@ 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;
 
@@ -3905,7 +3846,7 @@ 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);
@@ -4071,7 +4012,7 @@ 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);
@@ -4408,7 +4349,7 @@ 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;
@@ -4428,7 +4369,7 @@ 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);
@@ -4604,7 +4545,7 @@ err_af:
 }
 
 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
- * and sctp_sendmsg(3) as described in Documentation/security/LSM-sctp.rst
+ * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
  */
 static int selinux_socket_connect_helper(struct socket *sock,
                                          struct sockaddr *address, int addrlen)
@@ -5309,7 +5250,7 @@ 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,
@@ -5784,51 +5725,22 @@ 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)
 {
@@ -5836,7 +5748,7 @@ 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;
@@ -5850,11 +5762,6 @@ 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)
 {
@@ -5863,11 +5770,8 @@ 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;
@@ -5875,16 +5779,7 @@ 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)
@@ -5893,7 +5788,7 @@ 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;
@@ -5942,8 +5837,8 @@ 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
@@ -5990,8 +5885,8 @@ 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;
@@ -6014,11 +5909,8 @@ 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;
@@ -6026,16 +5918,7 @@ 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)
@@ -6044,7 +5927,7 @@ 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;
@@ -6111,11 +5994,8 @@ 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;
@@ -6123,16 +6003,7 @@ 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)
@@ -6141,7 +6012,7 @@ 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;
@@ -6227,7 +6098,7 @@ 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;
 }
 
@@ -6246,7 +6117,7 @@ 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,
@@ -6369,7 +6240,7 @@ 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")) {
@@ -6453,7 +6324,7 @@ 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;
@@ -6465,7 +6336,10 @@ static void selinux_inode_invalidate_secctx(struct inode *inode)
  */
 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
 {
-        return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
+        int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
+                                           ctx, ctxlen, 0);
+        /* Do not return error when suppressing label (SBLABEL_MNT not set). */
+        return rc == -EOPNOTSUPP ? 0 : rc;
 }
 
 /*
@@ -6498,7 +6372,7 @@ 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
@@ -6761,6 +6635,14 @@ 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),
@@ -6833,7 +6715,6 @@ 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),
@@ -6847,8 +6728,6 @@ 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),
@@ -6876,24 +6755,20 @@ 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),
@@ -7004,16 +6879,6 @@ 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));
@@ -7027,12 +6892,6 @@ 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();
@@ -7077,6 +6936,9 @@ 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,
 };