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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  *  Simplified MAC Kernel (smack) security module
  *
  *  This file contains the smack hook function implementations.
  *
  *  Authors:
  *  Casey Schaufler <casey@schaufler-ca.com>
  *  Jarkko Sakkinen <jarkko.sakkinen@intel.com>
  *
  *  Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
  *  Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
  *                Paul Moore <paul@paul-moore.com>
  *  Copyright (C) 2010 Nokia Corporation
  *  Copyright (C) 2011 Intel Corporation.
  */
 
 #include <linux/xattr.h>
 #include <linux/pagemap.h>
 #include <linux/mount.h>
 #include <linux/stat.h>
 #include <linux/kd.h>
 #include <asm/ioctls.h>
 #include <linux/ip.h>
 #include <linux/tcp.h>
 #include <linux/udp.h>
 #include <linux/dccp.h>
 #include <linux/icmpv6.h>
 #include <linux/slab.h>
 #include <linux/mutex.h>
 #include <net/cipso_ipv4.h>
 #include <net/ip.h>
 #include <net/ipv6.h>
 #include <linux/audit.h>
 #include <linux/magic.h>
 #include <linux/dcache.h>
 #include <linux/personality.h>
 #include <linux/msg.h>
 #include <linux/shm.h>
 #include <linux/binfmts.h>
 #include <linux/parser.h>
 #include <linux/fs_context.h>
 #include <linux/fs_parser.h>
 #include <linux/watch_queue.h>
 #include <linux/io_uring.h>
 #include "smack.h"
 
 #define TRANS_TRUE  "TRUE"
 #define TRANS_TRUE_SIZE 4
 
 #define SMK_CONNECTING  0
 #define SMK_RECEIVING   1
 #define SMK_SENDING 2
 
 #ifdef SMACK_IPV6_PORT_LABELING
 static DEFINE_MUTEX(smack_ipv6_lock);
 static LIST_HEAD(smk_ipv6_port_list);
 #endif
 struct kmem_cache *smack_rule_cache;
 int smack_enabled __initdata;
 
 #define A(s) {"smack"#s, sizeof("smack"#s) - 1, Opt_##s}
 static struct {
     const char *name;
     int len;
     int opt;
 } smk_mount_opts[] = {
     {"smackfsdef", sizeof("smackfsdef") - 1, Opt_fsdefault},
     A(fsdefault), A(fsfloor), A(fshat), A(fsroot), A(fstransmute)
 };
 #undef A
 
 static int match_opt_prefix(char *s, int l, char **arg)
 {
     int i;
 
     for (i = 0; i < ARRAY_SIZE(smk_mount_opts); i++) {
         size_t len = smk_mount_opts[i].len;
         if (len > l || memcmp(s, smk_mount_opts[i].name, len))
             continue;
         if (len == l || s[len] != '=')
             continue;
         *arg = s + len + 1;
         return smk_mount_opts[i].opt;
     }
     return Opt_error;
 }
 
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
 static char *smk_bu_mess[] = {
     "Bringup Error",    /* Unused */
     "Bringup",      /* SMACK_BRINGUP_ALLOW */
     "Unconfined Subject",   /* SMACK_UNCONFINED_SUBJECT */
     "Unconfined Object",    /* SMACK_UNCONFINED_OBJECT */
 };
 
 static void smk_bu_mode(int mode, char *s)
 {
     int i = 0;
 
     if (mode & MAY_READ)
         s[i++] = 'r';
     if (mode & MAY_WRITE)
         s[i++] = 'w';
     if (mode & MAY_EXEC)
         s[i++] = 'x';
     if (mode & MAY_APPEND)
         s[i++] = 'a';
     if (mode & MAY_TRANSMUTE)
         s[i++] = 't';
     if (mode & MAY_LOCK)
         s[i++] = 'l';
     if (i == 0)
         s[i++] = '-';
     s[i] = '\0';
 }
 #endif
 
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
 static int smk_bu_note(char *note, struct smack_known *sskp,
                struct smack_known *oskp, int mode, int rc)
 {
     char acc[SMK_NUM_ACCESS_TYPE + 1];
 
     if (rc <= 0)
         return rc;
     if (rc > SMACK_UNCONFINED_OBJECT)
         rc = 0;
 
     smk_bu_mode(mode, acc);
     pr_info("Smack %s: (%s %s %s) %s\n", smk_bu_mess[rc],
         sskp->smk_known, oskp->smk_known, acc, note);
     return 0;
 }
 #else
 #define smk_bu_note(note, sskp, oskp, mode, RC) (RC)
 #endif
 
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
 static int smk_bu_current(char *note, struct smack_known *oskp,
               int mode, int rc)
 {
     struct task_smack *tsp = smack_cred(current_cred());
     char acc[SMK_NUM_ACCESS_TYPE + 1];
 
     if (rc <= 0)
         return rc;
     if (rc > SMACK_UNCONFINED_OBJECT)
         rc = 0;
 
     smk_bu_mode(mode, acc);
     pr_info("Smack %s: (%s %s %s) %s %s\n", smk_bu_mess[rc],
         tsp->smk_task->smk_known, oskp->smk_known,
         acc, current->comm, note);
     return 0;
 }
 #else
 #define smk_bu_current(note, oskp, mode, RC) (RC)
 #endif
 
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
 static int smk_bu_task(struct task_struct *otp, int mode, int rc)
 {
     struct task_smack *tsp = smack_cred(current_cred());
     struct smack_known *smk_task = smk_of_task_struct_obj(otp);
     char acc[SMK_NUM_ACCESS_TYPE + 1];
 
     if (rc <= 0)
         return rc;
     if (rc > SMACK_UNCONFINED_OBJECT)
         rc = 0;
 
     smk_bu_mode(mode, acc);
     pr_info("Smack %s: (%s %s %s) %s to %s\n", smk_bu_mess[rc],
         tsp->smk_task->smk_known, smk_task->smk_known, acc,
         current->comm, otp->comm);
     return 0;
 }
 #else
 #define smk_bu_task(otp, mode, RC) (RC)
 #endif
 
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
 static int smk_bu_inode(struct inode *inode, int mode, int rc)
 {
     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)
         pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
             inode->i_sb->s_id, inode->i_ino, current->comm);
 
     if (rc <= 0)
         return rc;
     if (rc > SMACK_UNCONFINED_OBJECT)
         rc = 0;
     if (rc == SMACK_UNCONFINED_SUBJECT &&
         (mode & (MAY_WRITE | MAY_APPEND)))
         isp->smk_flags |= SMK_INODE_IMPURE;
 
     smk_bu_mode(mode, acc);
 
     pr_info("Smack %s: (%s %s %s) inode=(%s %ld) %s\n", smk_bu_mess[rc],
         tsp->smk_task->smk_known, isp->smk_inode->smk_known, acc,
         inode->i_sb->s_id, inode->i_ino, current->comm);
     return 0;
 }
 #else
 #define smk_bu_inode(inode, mode, RC) (RC)
 #endif
 
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
 static int smk_bu_file(struct file *file, int mode, int rc)
 {
     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 = smack_inode(inode);
     char acc[SMK_NUM_ACCESS_TYPE + 1];
 
     if (isp->smk_flags & SMK_INODE_IMPURE)
         pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
             inode->i_sb->s_id, inode->i_ino, current->comm);
 
     if (rc <= 0)
         return rc;
     if (rc > SMACK_UNCONFINED_OBJECT)
         rc = 0;
 
     smk_bu_mode(mode, acc);
     pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
         sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
         inode->i_sb->s_id, inode->i_ino, file,
         current->comm);
     return 0;
 }
 #else
 #define smk_bu_file(file, mode, RC) (RC)
 #endif
 
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
 static int smk_bu_credfile(const struct cred *cred, struct file *file,
                 int mode, int rc)
 {
     struct task_smack *tsp = smack_cred(cred);
     struct smack_known *sskp = tsp->smk_task;
     struct inode *inode = file_inode(file);
     struct inode_smack *isp = smack_inode(inode);
     char acc[SMK_NUM_ACCESS_TYPE + 1];
 
     if (isp->smk_flags & SMK_INODE_IMPURE)
         pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
             inode->i_sb->s_id, inode->i_ino, current->comm);
 
     if (rc <= 0)
         return rc;
     if (rc > SMACK_UNCONFINED_OBJECT)
         rc = 0;
 
     smk_bu_mode(mode, acc);
     pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
         sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
         inode->i_sb->s_id, inode->i_ino, file,
         current->comm);
     return 0;
 }
 #else
 #define smk_bu_credfile(cred, file, mode, RC) (RC)
 #endif
 
 /**
  * smk_fetch - Fetch the smack label from a file.
  * @name: type of the label (attribute)
  * @ip: a pointer to the inode
  * @dp: a pointer to the dentry
  *
  * Returns a pointer to the master list entry for the Smack label,
  * NULL if there was no label to fetch, or an error code.
  */
 static struct smack_known *smk_fetch(const char *name, struct inode *ip,
                     struct dentry *dp)
 {
     int rc;
     char *buffer;
     struct smack_known *skp = NULL;
 
     if (!(ip->i_opflags & IOP_XATTR))
         return ERR_PTR(-EOPNOTSUPP);
 
     buffer = kzalloc(SMK_LONGLABEL, GFP_NOFS);
     if (buffer == NULL)
         return ERR_PTR(-ENOMEM);
 
     rc = __vfs_getxattr(dp, ip, name, buffer, SMK_LONGLABEL);
     if (rc < 0)
         skp = ERR_PTR(rc);
     else if (rc == 0)
         skp = NULL;
     else
         skp = smk_import_entry(buffer, rc);
 
     kfree(buffer);
 
     return skp;
 }
 
 /**
  * init_inode_smack - initialize an inode security blob
  * @inode: inode to extract the info from
  * @skp: a pointer to the Smack label entry to use in the blob
  *
  */
 static void init_inode_smack(struct inode *inode, struct smack_known *skp)
 {
     struct inode_smack *isp = smack_inode(inode);
 
     isp->smk_inode = skp;
     isp->smk_flags = 0;
 }
 
 /**
  * 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
  *
  */
 static void init_task_smack(struct task_smack *tsp, struct smack_known *task,
                     struct smack_known *forked)
 {
     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);
 }
 
 /**
  * smk_copy_rules - copy a rule set
  * @nhead: new rules header pointer
  * @ohead: old rules header pointer
  * @gfp: type of the memory for the allocation
  *
  * Returns 0 on success, -ENOMEM on error
  */
 static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead,
                 gfp_t gfp)
 {
     struct smack_rule *nrp;
     struct smack_rule *orp;
     int rc = 0;
 
     list_for_each_entry_rcu(orp, ohead, list) {
         nrp = kmem_cache_zalloc(smack_rule_cache, gfp);
         if (nrp == NULL) {
             rc = -ENOMEM;
             break;
         }
         *nrp = *orp;
         list_add_rcu(&nrp->list, nhead);
     }
     return rc;
 }
 
 /**
  * smk_copy_relabel - copy smk_relabel labels list
  * @nhead: new rules header pointer
  * @ohead: old rules header pointer
  * @gfp: type of the memory for the allocation
  *
  * Returns 0 on success, -ENOMEM on error
  */
 static int smk_copy_relabel(struct list_head *nhead, struct list_head *ohead,
                 gfp_t gfp)
 {
     struct smack_known_list_elem *nklep;
     struct smack_known_list_elem *oklep;
 
     list_for_each_entry(oklep, ohead, list) {
         nklep = kzalloc(sizeof(struct smack_known_list_elem), gfp);
         if (nklep == NULL) {
             smk_destroy_label_list(nhead);
             return -ENOMEM;
         }
         nklep->smk_label = oklep->smk_label;
         list_add(&nklep->list, nhead);
     }
 
     return 0;
 }
 
 /**
  * smk_ptrace_mode - helper function for converting PTRACE_MODE_* into MAY_*
  * @mode: input mode in form of PTRACE_MODE_*
  *
  * Returns a converted MAY_* mode usable by smack rules
  */
 static inline unsigned int smk_ptrace_mode(unsigned int mode)
 {
     if (mode & PTRACE_MODE_ATTACH)
         return MAY_READWRITE;
     if (mode & PTRACE_MODE_READ)
         return MAY_READ;
 
     return 0;
 }
 
 /**
  * smk_ptrace_rule_check - helper for ptrace access
  * @tracer: tracer process
  * @tracee_known: label entry of the process that's about to be traced
  * @mode: ptrace attachment mode (PTRACE_MODE_*)
  * @func: name of the function that called us, used for audit
  *
  * Returns 0 on access granted, -error on error
  */
 static int smk_ptrace_rule_check(struct task_struct *tracer,
                  struct smack_known *tracee_known,
                  unsigned int mode, const char *func)
 {
     int rc;
     struct smk_audit_info ad, *saip = NULL;
     struct task_smack *tsp;
     struct smack_known *tracer_known;
     const struct cred *tracercred;
 
     if ((mode & PTRACE_MODE_NOAUDIT) == 0) {
         smk_ad_init(&ad, func, LSM_AUDIT_DATA_TASK);
         smk_ad_setfield_u_tsk(&ad, tracer);
         saip = &ad;
     }
 
     rcu_read_lock();
     tracercred = __task_cred(tracer);
     tsp = smack_cred(tracercred);
     tracer_known = smk_of_task(tsp);
 
     if ((mode & PTRACE_MODE_ATTACH) &&
         (smack_ptrace_rule == SMACK_PTRACE_EXACT ||
          smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)) {
         if (tracer_known->smk_known == tracee_known->smk_known)
             rc = 0;
         else if (smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)
             rc = -EACCES;
         else if (smack_privileged_cred(CAP_SYS_PTRACE, tracercred))
             rc = 0;
         else
             rc = -EACCES;
 
         if (saip)
             smack_log(tracer_known->smk_known,
                   tracee_known->smk_known,
                   0, rc, saip);
 
         rcu_read_unlock();
         return rc;
     }
 
     /* In case of rule==SMACK_PTRACE_DEFAULT or mode==PTRACE_MODE_READ */
     rc = smk_tskacc(tsp, tracee_known, smk_ptrace_mode(mode), saip);
 
     rcu_read_unlock();
     return rc;
 }
 
 /*
  * LSM hooks.
  * We he, that is fun!
  */
 
 /**
  * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH
  * @ctp: child task pointer
  * @mode: ptrace attachment mode (PTRACE_MODE_*)
  *
  * Returns 0 if access is OK, an error code otherwise
  *
  * Do the capability checks.
  */
 static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
 {
     struct smack_known *skp;
 
     skp = smk_of_task_struct_obj(ctp);
 
     return smk_ptrace_rule_check(current, skp, mode, __func__);
 }
 
 /**
  * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
  * @ptp: parent task pointer
  *
  * Returns 0 if access is OK, an error code otherwise
  *
  * Do the capability checks, and require PTRACE_MODE_ATTACH.
  */
 static int smack_ptrace_traceme(struct task_struct *ptp)
 {
     int rc;
     struct smack_known *skp;
 
     skp = smk_of_task(smack_cred(current_cred()));
 
     rc = smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__);
     return rc;
 }
 
 /**
  * smack_syslog - Smack approval on syslog
  * @typefrom_file: unused
  *
  * Returns 0 on success, error code otherwise.
  */
 static int smack_syslog(int typefrom_file)
 {
     int rc = 0;
     struct smack_known *skp = smk_of_current();
 
     if (smack_privileged(CAP_MAC_OVERRIDE))
         return 0;
 
     if (smack_syslog_label != NULL && smack_syslog_label != skp)
         rc = -EACCES;
 
     return rc;
 }
 
 /*
  * Superblock Hooks.
  */
 
 /**
  * smack_sb_alloc_security - allocate a superblock blob
  * @sb: the superblock getting the blob
  *
  * Returns 0 on success or -ENOMEM on error.
  */
 static int smack_sb_alloc_security(struct super_block *sb)
 {
     struct superblock_smack *sbsp = smack_superblock(sb);
 
     sbsp->smk_root = &smack_known_floor;
     sbsp->smk_default = &smack_known_floor;
     sbsp->smk_floor = &smack_known_floor;
     sbsp->smk_hat = &smack_known_hat;
     /*
      * SMK_SB_INITIALIZED will be zero from kzalloc.
      */
 
     return 0;
 }
 
 struct smack_mnt_opts {
     const char *fsdefault, *fsfloor, *fshat, *fsroot, *fstransmute;
 };
 
 static void smack_free_mnt_opts(void *mnt_opts)
 {
     struct smack_mnt_opts *opts = mnt_opts;
     kfree(opts->fsdefault);
     kfree(opts->fsfloor);
     kfree(opts->fshat);
     kfree(opts->fsroot);
     kfree(opts->fstransmute);
     kfree(opts);
 }
 
 static int smack_add_opt(int token, const char *s, void **mnt_opts)
 {
     struct smack_mnt_opts *opts = *mnt_opts;
 
     if (!opts) {
         opts = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL);
         if (!opts)
             return -ENOMEM;
         *mnt_opts = opts;
     }
     if (!s)
         return -ENOMEM;
 
     switch (token) {
     case Opt_fsdefault:
         if (opts->fsdefault)
             goto out_opt_err;
         opts->fsdefault = s;
         break;
     case Opt_fsfloor:
         if (opts->fsfloor)
             goto out_opt_err;
         opts->fsfloor = s;
         break;
     case Opt_fshat:
         if (opts->fshat)
             goto out_opt_err;
         opts->fshat = s;
         break;
     case Opt_fsroot:
         if (opts->fsroot)
             goto out_opt_err;
         opts->fsroot = s;
         break;
     case Opt_fstransmute:
         if (opts->fstransmute)
             goto out_opt_err;
         opts->fstransmute = s;
         break;
     }
     return 0;
 
 out_opt_err:
     pr_warn("Smack: duplicate mount options\n");
     return -EINVAL;
 }
 
 /**
  * smack_fs_context_dup - Duplicate the security data on fs_context duplication
  * @fc: The new filesystem context.
  * @src_fc: The source filesystem context being duplicated.
  *
  * Returns 0 on success or -ENOMEM on error.
  */
 static int smack_fs_context_dup(struct fs_context *fc,
                 struct fs_context *src_fc)
 {
     struct smack_mnt_opts *dst, *src = src_fc->security;
 
     if (!src)
         return 0;
 
     fc->security = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL);
     if (!fc->security)
         return -ENOMEM;
     dst = fc->security;
 
     if (src->fsdefault) {
         dst->fsdefault = kstrdup(src->fsdefault, GFP_KERNEL);
         if (!dst->fsdefault)
             return -ENOMEM;
     }
     if (src->fsfloor) {
         dst->fsfloor = kstrdup(src->fsfloor, GFP_KERNEL);
         if (!dst->fsfloor)
             return -ENOMEM;
     }
     if (src->fshat) {
         dst->fshat = kstrdup(src->fshat, GFP_KERNEL);
         if (!dst->fshat)
             return -ENOMEM;
     }
     if (src->fsroot) {
         dst->fsroot = kstrdup(src->fsroot, GFP_KERNEL);
         if (!dst->fsroot)
             return -ENOMEM;
     }
     if (src->fstransmute) {
         dst->fstransmute = kstrdup(src->fstransmute, GFP_KERNEL);
         if (!dst->fstransmute)
             return -ENOMEM;
     }
     return 0;
 }
 
 static const struct fs_parameter_spec smack_fs_parameters[] = {
     fsparam_string("smackfsdef",        Opt_fsdefault),
     fsparam_string("smackfsdefault",    Opt_fsdefault),
     fsparam_string("smackfsfloor",      Opt_fsfloor),
     fsparam_string("smackfshat",        Opt_fshat),
     fsparam_string("smackfsroot",       Opt_fsroot),
     fsparam_string("smackfstransmute",  Opt_fstransmute),
     {}
 };
 
 /**
  * smack_fs_context_parse_param - Parse a single mount parameter
  * @fc: The new filesystem context being constructed.
  * @param: The parameter.
  *
  * Returns 0 on success, -ENOPARAM to pass the parameter on or anything else on
  * error.
  */
 static int smack_fs_context_parse_param(struct fs_context *fc,
                     struct fs_parameter *param)
 {
     struct fs_parse_result result;
     int opt, rc;
 
     opt = fs_parse(fc, smack_fs_parameters, param, &result);
     if (opt < 0)
         return opt;
 
     rc = smack_add_opt(opt, param->string, &fc->security);
     if (!rc)
         param->string = NULL;
     return rc;
 }
 
 static int smack_sb_eat_lsm_opts(char *options, void **mnt_opts)
 {
     char *from = options, *to = options;
     bool first = true;
 
     while (1) {
         char *next = strchr(from, ',');
         int token, len, rc;
         char *arg = NULL;
 
         if (next)
             len = next - from;
         else
             len = strlen(from);
 
         token = match_opt_prefix(from, len, &arg);
         if (token != Opt_error) {
             arg = kmemdup_nul(arg, from + len - arg, GFP_KERNEL);
             rc = smack_add_opt(token, arg, mnt_opts);
             if (unlikely(rc)) {
                 kfree(arg);
                 if (*mnt_opts)
                     smack_free_mnt_opts(*mnt_opts);
                 *mnt_opts = NULL;
                 return rc;
             }
         } else {
             if (!first) {   // copy with preceding comma
                 from--;
                 len++;
             }
             if (to != from)
                 memmove(to, from, len);
             to += len;
             first = false;
         }
         if (!from[len])
             break;
         from += len + 1;
     }
     *to = '\0';
     return 0;
 }
 
 /**
  * smack_set_mnt_opts - set Smack specific mount options
  * @sb: the file system superblock
  * @mnt_opts: Smack mount options
  * @kern_flags: mount option from kernel space or user space
  * @set_kern_flags: where to store converted mount opts
  *
  * Returns 0 on success, an error code on failure
  *
  * Allow filesystems with binary mount data to explicitly set Smack mount
  * labels.
  */
 static int smack_set_mnt_opts(struct super_block *sb,
         void *mnt_opts,
         unsigned long kern_flags,
         unsigned long *set_kern_flags)
 {
     struct dentry *root = sb->s_root;
     struct inode *inode = d_backing_inode(root);
     struct superblock_smack *sp = smack_superblock(sb);
     struct inode_smack *isp;
     struct smack_known *skp;
     struct smack_mnt_opts *opts = mnt_opts;
     bool transmute = false;
 
     if (sp->smk_flags & SMK_SB_INITIALIZED)
         return 0;
 
     if (!smack_privileged(CAP_MAC_ADMIN)) {
         /*
          * Unprivileged mounts don't get to specify Smack values.
          */
         if (opts)
             return -EPERM;
         /*
          * Unprivileged mounts get root and default from the caller.
          */
         skp = smk_of_current();
         sp->smk_root = skp;
         sp->smk_default = skp;
         /*
          * For a handful of fs types with no user-controlled
          * backing store it's okay to trust security labels
          * in the filesystem. The rest are untrusted.
          */
         if (sb->s_user_ns != &init_user_ns &&
             sb->s_magic != SYSFS_MAGIC && sb->s_magic != TMPFS_MAGIC &&
             sb->s_magic != RAMFS_MAGIC) {
             transmute = true;
             sp->smk_flags |= SMK_SB_UNTRUSTED;
         }
     }
 
     sp->smk_flags |= SMK_SB_INITIALIZED;
 
     if (opts) {
         if (opts->fsdefault) {
             skp = smk_import_entry(opts->fsdefault, 0);
             if (IS_ERR(skp))
                 return PTR_ERR(skp);
             sp->smk_default = skp;
         }
         if (opts->fsfloor) {
             skp = smk_import_entry(opts->fsfloor, 0);
             if (IS_ERR(skp))
                 return PTR_ERR(skp);
             sp->smk_floor = skp;
         }
         if (opts->fshat) {
             skp = smk_import_entry(opts->fshat, 0);
             if (IS_ERR(skp))
                 return PTR_ERR(skp);
             sp->smk_hat = skp;
         }
         if (opts->fsroot) {
             skp = smk_import_entry(opts->fsroot, 0);
             if (IS_ERR(skp))
                 return PTR_ERR(skp);
             sp->smk_root = skp;
         }
         if (opts->fstransmute) {
             skp = smk_import_entry(opts->fstransmute, 0);
             if (IS_ERR(skp))
                 return PTR_ERR(skp);
             sp->smk_root = skp;
             transmute = true;
         }
     }
 
     /*
      * Initialize the root inode.
      */
     init_inode_smack(inode, sp->smk_root);
 
     if (transmute) {
         isp = smack_inode(inode);
         isp->smk_flags |= SMK_INODE_TRANSMUTE;
     }
 
     return 0;
 }
 
 /**
  * smack_sb_statfs - Smack check on statfs
  * @dentry: identifies the file system in question
  *
  * Returns 0 if current can read the floor of the filesystem,
  * and error code otherwise
  */
 static int smack_sb_statfs(struct dentry *dentry)
 {
     struct superblock_smack *sbp = smack_superblock(dentry->d_sb);
     int rc;
     struct smk_audit_info ad;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
     smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
     rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
     rc = smk_bu_current("statfs", sbp->smk_floor, MAY_READ, rc);
     return rc;
 }
 
 /*
  * BPRM hooks
  */
 
 /**
  * smack_bprm_creds_for_exec - Update bprm->cred if needed for exec
  * @bprm: the exec information
  *
  * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise
  */
 static int smack_bprm_creds_for_exec(struct linux_binprm *bprm)
 {
     struct inode *inode = file_inode(bprm->file);
     struct task_smack *bsp = smack_cred(bprm->cred);
     struct inode_smack *isp;
     struct superblock_smack *sbsp;
     int rc;
 
     isp = smack_inode(inode);
     if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
         return 0;
 
     sbsp = smack_superblock(inode->i_sb);
     if ((sbsp->smk_flags & SMK_SB_UNTRUSTED) &&
         isp->smk_task != sbsp->smk_root)
         return 0;
 
     if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
         struct task_struct *tracer;
         rc = 0;
 
         rcu_read_lock();
         tracer = ptrace_parent(current);
         if (likely(tracer != NULL))
             rc = smk_ptrace_rule_check(tracer,
                            isp->smk_task,
                            PTRACE_MODE_ATTACH,
                            __func__);
         rcu_read_unlock();
 
         if (rc != 0)
             return rc;
     }
     if (bprm->unsafe & ~LSM_UNSAFE_PTRACE)
         return -EPERM;
 
     bsp->smk_task = isp->smk_task;
     bprm->per_clear |= PER_CLEAR_ON_SETID;
 
     /* Decide if this is a secure exec. */
     if (bsp->smk_task != bsp->smk_forked)
         bprm->secureexec = 1;
 
     return 0;
 }
 
 /*
  * Inode hooks
  */
 
 /**
  * smack_inode_alloc_security - allocate an inode blob
  * @inode: the inode in need of a blob
  *
  * Returns 0
  */
 static int smack_inode_alloc_security(struct inode *inode)
 {
     struct smack_known *skp = smk_of_current();
 
     init_inode_smack(inode, skp);
     return 0;
 }
 
 /**
  * smack_inode_init_security - copy out the smack from an inode
  * @inode: the newly created inode
  * @dir: containing directory object
  * @qstr: unused
  * @name: where to put the attribute name
  * @value: where to put the attribute value
  * @len: where to put the length of the attribute
  *
  * Returns 0 if it all works out, -ENOMEM if there's no memory
  */
 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 = 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);
     int may;
 
     if (name)
         *name = XATTR_SMACK_SUFFIX;
 
     if (value && len) {
         rcu_read_lock();
         may = smk_access_entry(skp->smk_known, dsp->smk_known,
                        &skp->smk_rules);
         rcu_read_unlock();
 
         /*
          * If the access rule allows transmutation and
          * the directory requests transmutation then
          * by all means transmute.
          * Mark the inode as changed.
          */
         if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
             smk_inode_transmutable(dir)) {
             isp = dsp;
             issp->smk_flags |= SMK_INODE_CHANGED;
         }
 
         *value = kstrdup(isp->smk_known, GFP_NOFS);
         if (*value == NULL)
             return -ENOMEM;
 
         *len = strlen(isp->smk_known);
     }
 
     return 0;
 }
 
 /**
  * smack_inode_link - Smack check on link
  * @old_dentry: the existing object
  * @dir: unused
  * @new_dentry: the new object
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
 static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
                 struct dentry *new_dentry)
 {
     struct smack_known *isp;
     struct smk_audit_info ad;
     int rc;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
     smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
 
     isp = smk_of_inode(d_backing_inode(old_dentry));
     rc = smk_curacc(isp, MAY_WRITE, &ad);
     rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_WRITE, rc);
 
     if (rc == 0 && d_is_positive(new_dentry)) {
         isp = smk_of_inode(d_backing_inode(new_dentry));
         smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
         rc = smk_curacc(isp, MAY_WRITE, &ad);
         rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_WRITE, rc);
     }
 
     return rc;
 }
 
 /**
  * smack_inode_unlink - Smack check on inode deletion
  * @dir: containing directory object
  * @dentry: file to unlink
  *
  * Returns 0 if current can write the containing directory
  * and the object, error code otherwise
  */
 static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
 {
     struct inode *ip = d_backing_inode(dentry);
     struct smk_audit_info ad;
     int rc;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
     smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
     /*
      * You need write access to the thing you're unlinking
      */
     rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
     rc = smk_bu_inode(ip, MAY_WRITE, rc);
     if (rc == 0) {
         /*
          * You also need write access to the containing directory
          */
         smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
         smk_ad_setfield_u_fs_inode(&ad, dir);
         rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
         rc = smk_bu_inode(dir, MAY_WRITE, rc);
     }
     return rc;
 }
 
 /**
  * smack_inode_rmdir - Smack check on directory deletion
  * @dir: containing directory object
  * @dentry: directory to unlink
  *
  * Returns 0 if current can write the containing directory
  * and the directory, error code otherwise
  */
 static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
 {
     struct smk_audit_info ad;
     int rc;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
     smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
     /*
      * You need write access to the thing you're removing
      */
     rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
     rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
     if (rc == 0) {
         /*
          * You also need write access to the containing directory
          */
         smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
         smk_ad_setfield_u_fs_inode(&ad, dir);
         rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
         rc = smk_bu_inode(dir, MAY_WRITE, rc);
     }
 
     return rc;
 }
 
 /**
  * smack_inode_rename - Smack check on rename
  * @old_inode: unused
  * @old_dentry: the old object
  * @new_inode: unused
  * @new_dentry: the new object
  *
  * Read and write access is required on both the old and
  * new directories.
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
 static int smack_inode_rename(struct inode *old_inode,
                   struct dentry *old_dentry,
                   struct inode *new_inode,
                   struct dentry *new_dentry)
 {
     int rc;
     struct smack_known *isp;
     struct smk_audit_info ad;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
     smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
 
     isp = smk_of_inode(d_backing_inode(old_dentry));
     rc = smk_curacc(isp, MAY_READWRITE, &ad);
     rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_READWRITE, rc);
 
     if (rc == 0 && d_is_positive(new_dentry)) {
         isp = smk_of_inode(d_backing_inode(new_dentry));
         smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
         rc = smk_curacc(isp, MAY_READWRITE, &ad);
         rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_READWRITE, rc);
     }
     return rc;
 }
 
 /**
  * smack_inode_permission - Smack version of permission()
  * @inode: the inode in question
  * @mask: the access requested
  *
  * This is the important Smack hook.
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
 static int smack_inode_permission(struct inode *inode, int mask)
 {
     struct superblock_smack *sbsp = smack_superblock(inode->i_sb);
     struct smk_audit_info ad;
     int no_block = mask & MAY_NOT_BLOCK;
     int rc;
 
     mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
     /*
      * No permission to check. Existence test. Yup, it's there.
      */
     if (mask == 0)
         return 0;
 
     if (sbsp->smk_flags & SMK_SB_UNTRUSTED) {
         if (smk_of_inode(inode) != sbsp->smk_root)
             return -EACCES;
     }
 
     /* May be droppable after audit */
     if (no_block)
         return -ECHILD;
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
     smk_ad_setfield_u_fs_inode(&ad, inode);
     rc = smk_curacc(smk_of_inode(inode), mask, &ad);
     rc = smk_bu_inode(inode, mask, rc);
     return rc;
 }
 
 /**
  * smack_inode_setattr - Smack check for setting attributes
  * @dentry: the object
  * @iattr: for the force flag
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
 static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
 {
     struct smk_audit_info ad;
     int rc;
 
     /*
      * Need to allow for clearing the setuid bit.
      */
     if (iattr->ia_valid & ATTR_FORCE)
         return 0;
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
     smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
     rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
     rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
     return rc;
 }
 
 /**
  * smack_inode_getattr - Smack check for getting attributes
  * @path: path to extract the info from
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
 static int smack_inode_getattr(const struct path *path)
 {
     struct smk_audit_info ad;
     struct inode *inode = d_backing_inode(path->dentry);
     int rc;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
     smk_ad_setfield_u_fs_path(&ad, *path);
     rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
     rc = smk_bu_inode(inode, MAY_READ, rc);
     return rc;
 }
 
 /**
  * smack_inode_setxattr - Smack check for setting xattrs
  * @mnt_userns: active user namespace
  * @dentry: the object
  * @name: name of the attribute
  * @value: value of the attribute
  * @size: size of the value
  * @flags: unused
  *
  * This protects the Smack attribute explicitly.
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
 static int smack_inode_setxattr(struct user_namespace *mnt_userns,
                 struct dentry *dentry, const char *name,
                 const void *value, size_t size, int flags)
 {
     struct smk_audit_info ad;
     struct smack_known *skp;
     int check_priv = 0;
     int check_import = 0;
     int check_star = 0;
     int rc = 0;
 
     /*
      * Check label validity here so import won't fail in post_setxattr
      */
     if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
         strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
         strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
         check_priv = 1;
         check_import = 1;
     } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
            strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
         check_priv = 1;
         check_import = 1;
         check_star = 1;
     } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
         check_priv = 1;
         if (size != TRANS_TRUE_SIZE ||
             strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
             rc = -EINVAL;
     } else
         rc = cap_inode_setxattr(dentry, name, value, size, flags);
 
     if (check_priv && !smack_privileged(CAP_MAC_ADMIN))
         rc = -EPERM;
 
     if (rc == 0 && check_import) {
         skp = size ? smk_import_entry(value, size) : NULL;
         if (IS_ERR(skp))
             rc = PTR_ERR(skp);
         else if (skp == NULL || (check_star &&
             (skp == &smack_known_star || skp == &smack_known_web)))
             rc = -EINVAL;
     }
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
     smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
     if (rc == 0) {
         rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
         rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
     }
 
     return rc;
 }
 
 /**
  * smack_inode_post_setxattr - Apply the Smack update approved above
  * @dentry: object
  * @name: attribute name
  * @value: attribute value
  * @size: attribute size
  * @flags: unused
  *
  * Set the pointer in the inode blob to the entry found
  * in the master label list.
  */
 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 = smack_inode(d_backing_inode(dentry));
 
     if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
         isp->smk_flags |= SMK_INODE_TRANSMUTE;
         return;
     }
 
     if (strcmp(name, XATTR_NAME_SMACK) == 0) {
         skp = smk_import_entry(value, size);
         if (!IS_ERR(skp))
             isp->smk_inode = skp;
     } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
         skp = smk_import_entry(value, size);
         if (!IS_ERR(skp))
             isp->smk_task = skp;
     } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
         skp = smk_import_entry(value, size);
         if (!IS_ERR(skp))
             isp->smk_mmap = skp;
     }
 
     return;
 }
 
 /**
  * smack_inode_getxattr - Smack check on getxattr
  * @dentry: the object
  * @name: unused
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
 static int smack_inode_getxattr(struct dentry *dentry, const char *name)
 {
     struct smk_audit_info ad;
     int rc;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
     smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
     rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad);
     rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
     return rc;
 }
 
 /**
  * smack_inode_removexattr - Smack check on removexattr
  * @mnt_userns: active user namespace
  * @dentry: the object
  * @name: name of the attribute
  *
  * Removing the Smack attribute requires CAP_MAC_ADMIN
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
 static int smack_inode_removexattr(struct user_namespace *mnt_userns,
                    struct dentry *dentry, const char *name)
 {
     struct inode_smack *isp;
     struct smk_audit_info ad;
     int rc = 0;
 
     if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
         strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
         strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
         strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
         strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
         strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
         if (!smack_privileged(CAP_MAC_ADMIN))
             rc = -EPERM;
     } else
         rc = cap_inode_removexattr(mnt_userns, dentry, name);
 
     if (rc != 0)
         return rc;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
     smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
     rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
     rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
     if (rc != 0)
         return rc;
 
     isp = smack_inode(d_backing_inode(dentry));
     /*
      * Don't do anything special for these.
      *  XATTR_NAME_SMACKIPIN
      *  XATTR_NAME_SMACKIPOUT
      */
     if (strcmp(name, XATTR_NAME_SMACK) == 0) {
         struct super_block *sbp = dentry->d_sb;
         struct superblock_smack *sbsp = smack_superblock(sbp);
 
         isp->smk_inode = sbsp->smk_default;
     } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0)
         isp->smk_task = NULL;
     else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0)
         isp->smk_mmap = NULL;
     else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
         isp->smk_flags &= ~SMK_INODE_TRANSMUTE;
 
     return 0;
 }
 
 /**
  * smack_inode_getsecurity - get smack xattrs
  * @mnt_userns: active user namespace
  * @inode: the object
  * @name: attribute name
  * @buffer: where to put the result
  * @alloc: duplicate memory
  *
  * Returns the size of the attribute or an error code
  */
 static int smack_inode_getsecurity(struct user_namespace *mnt_userns,
                    struct inode *inode, const char *name,
                    void **buffer, bool alloc)
 {
     struct socket_smack *ssp;
     struct socket *sock;
     struct super_block *sbp;
     struct inode *ip = (struct inode *)inode;
     struct smack_known *isp;
 
     if (strcmp(name, XATTR_SMACK_SUFFIX) == 0)
         isp = smk_of_inode(inode);
     else {
         /*
          * The rest of the Smack xattrs are only on sockets.
          */
         sbp = ip->i_sb;
         if (sbp->s_magic != SOCKFS_MAGIC)
             return -EOPNOTSUPP;
 
         sock = SOCKET_I(ip);
         if (sock == NULL || sock->sk == NULL)
             return -EOPNOTSUPP;
 
         ssp = sock->sk->sk_security;
 
         if (strcmp(name, XATTR_SMACK_IPIN) == 0)
             isp = ssp->smk_in;
         else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
             isp = ssp->smk_out;
         else
             return -EOPNOTSUPP;
     }
 
     if (alloc) {
         *buffer = kstrdup(isp->smk_known, GFP_KERNEL);
         if (*buffer == NULL)
             return -ENOMEM;
     }
 
     return strlen(isp->smk_known);
 }
 
 
 /**
  * smack_inode_listsecurity - list the Smack attributes
  * @inode: the object
  * @buffer: where they go
  * @buffer_size: size of buffer
  */
 static int smack_inode_listsecurity(struct inode *inode, char *buffer,
                     size_t buffer_size)
 {
     int len = sizeof(XATTR_NAME_SMACK);
 
     if (buffer != NULL && len <= buffer_size)
         memcpy(buffer, XATTR_NAME_SMACK, len);
 
     return len;
 }
 
 /**
  * smack_inode_getsecid - Extract inode's security id
  * @inode: inode to extract the info from
  * @secid: where result will be saved
  */
 static void smack_inode_getsecid(struct inode *inode, u32 *secid)
 {
     struct smack_known *skp = smk_of_inode(inode);
 
     *secid = skp->smk_secid;
 }
 
 /*
  * File Hooks
  */
 
 /*
  * There is no smack_file_permission hook
  *
  * Should access checks be done on each read or write?
  * UNICOS and SELinux say yes.
  * Trusted Solaris, Trusted Irix, and just about everyone else says no.
  *
  * I'll say no for now. Smack does not do the frequent
  * label changing that SELinux does.
  */
 
 /**
  * smack_file_alloc_security - assign a file security blob
  * @file: the object
  *
  * The security blob for a file is a pointer to the master
  * label list, so no allocation is done.
  *
  * f_security is the owner security information. It
  * isn't used on file access checks, it's for send_sigio.
  *
  * Returns 0
  */
 static int smack_file_alloc_security(struct file *file)
 {
     struct smack_known **blob = smack_file(file);
 
     *blob = smk_of_current();
     return 0;
 }
 
 /**
  * smack_file_ioctl - Smack check on ioctls
  * @file: the object
  * @cmd: what to do
  * @arg: unused
  *
  * Relies heavily on the correct use of the ioctl command conventions.
  *
  * Returns 0 if allowed, error code otherwise
  */
 static int smack_file_ioctl(struct file *file, unsigned int cmd,
                 unsigned long arg)
 {
     int rc = 0;
     struct smk_audit_info ad;
     struct inode *inode = file_inode(file);
 
     if (unlikely(IS_PRIVATE(inode)))
         return 0;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
     smk_ad_setfield_u_fs_path(&ad, file->f_path);
 
     if (_IOC_DIR(cmd) & _IOC_WRITE) {
         rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
         rc = smk_bu_file(file, MAY_WRITE, rc);
     }
 
     if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) {
         rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
         rc = smk_bu_file(file, MAY_READ, rc);
     }
 
     return rc;
 }
 
 /**
  * smack_file_lock - Smack check on file locking
  * @file: the object
  * @cmd: unused
  *
  * Returns 0 if current has lock access, error code otherwise
  */
 static int smack_file_lock(struct file *file, unsigned int cmd)
 {
     struct smk_audit_info ad;
     int rc;
     struct inode *inode = file_inode(file);
 
     if (unlikely(IS_PRIVATE(inode)))
         return 0;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
     smk_ad_setfield_u_fs_path(&ad, file->f_path);
     rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
     rc = smk_bu_file(file, MAY_LOCK, rc);
     return rc;
 }
 
 /**
  * smack_file_fcntl - Smack check on fcntl
  * @file: the object
  * @cmd: what action to check
  * @arg: unused
  *
  * Generally these operations are harmless.
  * File locking operations present an obvious mechanism
  * for passing information, so they require write access.
  *
  * Returns 0 if current has access, error code otherwise
  */
 static int smack_file_fcntl(struct file *file, unsigned int cmd,
                 unsigned long arg)
 {
     struct smk_audit_info ad;
     int rc = 0;
     struct inode *inode = file_inode(file);
 
     if (unlikely(IS_PRIVATE(inode)))
         return 0;
 
     switch (cmd) {
     case F_GETLK:
         break;
     case F_SETLK:
     case F_SETLKW:
         smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path(&ad, file->f_path);
         rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
         rc = smk_bu_file(file, MAY_LOCK, rc);
         break;
     case F_SETOWN:
     case F_SETSIG:
         smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
         smk_ad_setfield_u_fs_path(&ad, file->f_path);
         rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
         rc = smk_bu_file(file, MAY_WRITE, rc);
         break;
     default:
         break;
     }
 
     return rc;
 }
 
 /**
  * smack_mmap_file - Check permissions for a mmap operation.
  * @file: contains the file structure for file to map (may be NULL).
  * @reqprot: contains the protection requested by the application.
  * @prot: contains the protection that will be applied by the kernel.
  * @flags: contains the operational flags.
  *
  * The @file may be NULL, e.g. if mapping anonymous memory.
  *
  * Return 0 if permission is granted.
  */
 static int smack_mmap_file(struct file *file,
                unsigned long reqprot, unsigned long prot,
                unsigned long flags)
 {
     struct smack_known *skp;
     struct smack_known *mkp;
     struct smack_rule *srp;
     struct task_smack *tsp;
     struct smack_known *okp;
     struct inode_smack *isp;
     struct superblock_smack *sbsp;
     int may;
     int mmay;
     int tmay;
     int rc;
 
     if (file == NULL)
         return 0;
 
     if (unlikely(IS_PRIVATE(file_inode(file))))
         return 0;
 
     isp = smack_inode(file_inode(file));
     if (isp->smk_mmap == NULL)
         return 0;
     sbsp = smack_superblock(file_inode(file)->i_sb);
     if (sbsp->smk_flags & SMK_SB_UNTRUSTED &&
         isp->smk_mmap != sbsp->smk_root)
         return -EACCES;
     mkp = isp->smk_mmap;
 
     tsp = smack_cred(current_cred());
     skp = smk_of_current();
     rc = 0;
 
     rcu_read_lock();
     /*
      * For each Smack rule associated with the subject
      * label verify that the SMACK64MMAP also has access
      * to that rule's object label.
      */
     list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
         okp = srp->smk_object;
         /*
          * Matching labels always allows access.
          */
         if (mkp->smk_known == okp->smk_known)
             continue;
         /*
          * If there is a matching local rule take
          * that into account as well.
          */
         may = smk_access_entry(srp->smk_subject->smk_known,
                        okp->smk_known,
                        &tsp->smk_rules);
         if (may == -ENOENT)
             may = srp->smk_access;
         else
             may &= srp->smk_access;
         /*
          * If may is zero the SMACK64MMAP subject can't
          * possibly have less access.
          */
         if (may == 0)
             continue;
 
         /*
          * Fetch the global list entry.
          * If there isn't one a SMACK64MMAP subject
          * can't have as much access as current.
          */
         mmay = smk_access_entry(mkp->smk_known, okp->smk_known,
                     &mkp->smk_rules);
         if (mmay == -ENOENT) {
             rc = -EACCES;
             break;
         }
         /*
          * If there is a local entry it modifies the
          * potential access, too.
          */
         tmay = smk_access_entry(mkp->smk_known, okp->smk_known,
                     &tsp->smk_rules);
         if (tmay != -ENOENT)
             mmay &= tmay;
 
         /*
          * If there is any access available to current that is
          * not available to a SMACK64MMAP subject
          * deny access.
          */
         if ((may | mmay) != mmay) {
             rc = -EACCES;
             break;
         }
     }
 
     rcu_read_unlock();
 
     return rc;
 }
 
 /**
  * smack_file_set_fowner - set the file security blob value
  * @file: object in question
  *
  */
 static void smack_file_set_fowner(struct file *file)
 {
     struct smack_known **blob = smack_file(file);
 
     *blob = smk_of_current();
 }
 
 /**
  * smack_file_send_sigiotask - Smack on sigio
  * @tsk: The target task
  * @fown: the object the signal come from
  * @signum: unused
  *
  * Allow a privileged task to get signals even if it shouldn't
  *
  * Returns 0 if a subject with the object's smack could
  * write to the task, an error code otherwise.
  */
 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(smack_cred(tsk->cred));
     const struct cred *tcred;
     struct file *file;
     int rc;
     struct smk_audit_info ad;
 
     /*
      * struct fown_struct is never outside the context of a struct file
      */
     file = container_of(fown, struct file, f_owner);
 
     /* we don't log here as rc can be overriden */
     blob = smack_file(file);
     skp = *blob;
     rc = smk_access(skp, tkp, MAY_DELIVER, NULL);
     rc = smk_bu_note("sigiotask", skp, tkp, MAY_DELIVER, rc);
 
     rcu_read_lock();
     tcred = __task_cred(tsk);
     if (rc != 0 && smack_privileged_cred(CAP_MAC_OVERRIDE, tcred))
         rc = 0;
     rcu_read_unlock();
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
     smk_ad_setfield_u_tsk(&ad, tsk);
     smack_log(skp->smk_known, tkp->smk_known, MAY_DELIVER, rc, &ad);
     return rc;
 }
 
 /**
  * smack_file_receive - Smack file receive check
  * @file: the object
  *
  * Returns 0 if current has access, error code otherwise
  */
 static int smack_file_receive(struct file *file)
 {
     int rc;
     int may = 0;
     struct smk_audit_info ad;
     struct inode *inode = file_inode(file);
     struct socket *sock;
     struct task_smack *tsp;
     struct socket_smack *ssp;
 
     if (unlikely(IS_PRIVATE(inode)))
         return 0;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
     smk_ad_setfield_u_fs_path(&ad, file->f_path);
 
     if (inode->i_sb->s_magic == SOCKFS_MAGIC) {
         sock = SOCKET_I(inode);
         ssp = sock->sk->sk_security;
         tsp = smack_cred(current_cred());
         /*
          * If the receiving process can't write to the
          * passed socket or if the passed socket can't
          * write to the receiving process don't accept
          * the passed socket.
          */
         rc = smk_access(tsp->smk_task, ssp->smk_out, MAY_WRITE, &ad);
         rc = smk_bu_file(file, may, rc);
         if (rc < 0)
             return rc;
         rc = smk_access(ssp->smk_in, tsp->smk_task, MAY_WRITE, &ad);
         rc = smk_bu_file(file, may, rc);
         return rc;
     }
     /*
      * This code relies on bitmasks.
      */
     if (file->f_mode & FMODE_READ)
         may = MAY_READ;
     if (file->f_mode & FMODE_WRITE)
         may |= MAY_WRITE;
 
     rc = smk_curacc(smk_of_inode(inode), may, &ad);
     rc = smk_bu_file(file, may, rc);
     return rc;
 }
 
 /**
  * smack_file_open - Smack dentry open processing
  * @file: the object
  *
  * Set the security blob in the file structure.
  * Allow the open only if the task has read access. There are
  * many read operations (e.g. fstat) that you can do with an
  * fd even if you have the file open write-only.
  *
  * Returns 0 if current has access, error code otherwise
  */
 static int smack_file_open(struct file *file)
 {
     struct task_smack *tsp = smack_cred(file->f_cred);
     struct inode *inode = file_inode(file);
     struct smk_audit_info ad;
     int rc;
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
     smk_ad_setfield_u_fs_path(&ad, file->f_path);
     rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
     rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc);
 
     return rc;
 }
 
 /*
  * Task hooks
  */
 
 /**
  * smack_cred_alloc_blank - "allocate" blank task-level security credentials
  * @cred: the new credentials
  * @gfp: the atomicity of any memory allocations
  *
  * Prepare a blank set of credentials for modification.  This must allocate all
  * the memory the LSM module might require such that cred_transfer() can
  * complete without error.
  */
 static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
 {
     init_task_smack(smack_cred(cred), NULL, NULL);
     return 0;
 }
 
 
 /**
  * smack_cred_free - "free" task-level security credentials
  * @cred: the credentials in question
  *
  */
 static void smack_cred_free(struct cred *cred)
 {
     struct task_smack *tsp = smack_cred(cred);
     struct smack_rule *rp;
     struct list_head *l;
     struct list_head *n;
 
     smk_destroy_label_list(&tsp->smk_relabel);
 
     list_for_each_safe(l, n, &tsp->smk_rules) {
         rp = list_entry(l, struct smack_rule, list);
         list_del(&rp->list);
         kmem_cache_free(smack_rule_cache, rp);
     }
 }
 
 /**
  * smack_cred_prepare - prepare new set of credentials for modification
  * @new: the new credentials
  * @old: the original credentials
  * @gfp: the atomicity of any memory allocations
  *
  * Prepare a new set of credentials for modification.
  */
 static int smack_cred_prepare(struct cred *new, const struct cred *old,
                   gfp_t gfp)
 {
     struct task_smack *old_tsp = smack_cred(old);
     struct task_smack *new_tsp = smack_cred(new);
     int rc;
 
     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)
         return rc;
 
     rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel,
                 gfp);
     return rc;
 }
 
 /**
  * smack_cred_transfer - Transfer the old credentials to the new credentials
  * @new: the new credentials
  * @old: the original credentials
  *
  * Fill in a set of blank credentials from another set of credentials.
  */
 static void smack_cred_transfer(struct cred *new, const struct cred *old)
 {
     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 */
 }
 
 /**
  * smack_cred_getsecid - get the secid corresponding to a creds structure
  * @cred: the object creds
  * @secid: where to put the result
  *
  * Sets the secid to contain a u32 version of the smack label.
  */
 static void smack_cred_getsecid(const struct cred *cred, u32 *secid)
 {
     struct smack_known *skp;
 
     rcu_read_lock();
     skp = smk_of_task(smack_cred(cred));
     *secid = skp->smk_secid;
     rcu_read_unlock();
 }
 
 /**
  * smack_kernel_act_as - Set the subjective context in a set of credentials
  * @new: points to the set of credentials to be modified.
  * @secid: specifies the security ID to be set
  *
  * Set the security data for a kernel service.
  */
 static int smack_kernel_act_as(struct cred *new, u32 secid)
 {
     struct task_smack *new_tsp = smack_cred(new);
 
     new_tsp->smk_task = smack_from_secid(secid);
     return 0;
 }
 
 /**
  * smack_kernel_create_files_as - Set the file creation label in a set of creds
  * @new: points to the set of credentials to be modified
  * @inode: points to the inode to use as a reference
  *
  * Set the file creation context in a set of credentials to the same
  * as the objective context of the specified inode
  */
 static int smack_kernel_create_files_as(struct cred *new,
                     struct inode *inode)
 {
     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;
     return 0;
 }
 
 /**
  * smk_curacc_on_task - helper to log task related access
  * @p: the task object
  * @access: the access requested
  * @caller: name of the calling function for audit
  *
  * Return 0 if access is permitted
  */
 static int smk_curacc_on_task(struct task_struct *p, int access,
                 const char *caller)
 {
     struct smk_audit_info ad;
     struct smack_known *skp = smk_of_task_struct_obj(p);
     int rc;
 
     smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
     smk_ad_setfield_u_tsk(&ad, p);
     rc = smk_curacc(skp, access, &ad);
     rc = smk_bu_task(p, access, rc);
     return rc;
 }
 
 /**
  * smack_task_setpgid - Smack check on setting pgid
  * @p: the task object
  * @pgid: unused
  *
  * Return 0 if write access is permitted
  */
 static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
 {
     return smk_curacc_on_task(p, MAY_WRITE, __func__);
 }
 
 /**
  * smack_task_getpgid - Smack access check for getpgid
  * @p: the object task
  *
  * Returns 0 if current can read the object task, error code otherwise
  */
 static int smack_task_getpgid(struct task_struct *p)
 {
     return smk_curacc_on_task(p, MAY_READ, __func__);
 }
 
 /**
  * smack_task_getsid - Smack access check for getsid
  * @p: the object task
  *
  * Returns 0 if current can read the object task, error code otherwise
  */
 static int smack_task_getsid(struct task_struct *p)
 {
     return smk_curacc_on_task(p, MAY_READ, __func__);
 }
 
 /**
  * smack_current_getsecid_subj - get the subjective secid of the current task
  * @secid: where to put the result
  *
  * Sets the secid to contain a u32 version of the task's subjective smack label.
  */
 static void smack_current_getsecid_subj(u32 *secid)
 {
     struct smack_known *skp = smk_of_current();
 
     *secid = skp->smk_secid;
 }
 
 /**
  * smack_task_getsecid_obj - get the objective secid of the task
  * @p: the task
  * @secid: where to put the result
  *
  * Sets the secid to contain a u32 version of the task's objective smack label.
  */
 static void smack_task_getsecid_obj(struct task_struct *p, u32 *secid)
 {
     struct smack_known *skp = smk_of_task_struct_obj(p);
 
     *secid = skp->smk_secid;
 }
 
 /**
  * smack_task_setnice - Smack check on setting nice
  * @p: the task object
  * @nice: unused
  *
  * Return 0 if write access is permitted
  */
 static int smack_task_setnice(struct task_struct *p, int nice)
 {
     return smk_curacc_on_task(p, MAY_WRITE, __func__);
 }
 
 /**
  * smack_task_setioprio - Smack check on setting ioprio
  * @p: the task object
  * @ioprio: unused
  *
  * Return 0 if write access is permitted
  */
 static int smack_task_setioprio(struct task_struct *p, int ioprio)
 {
     return smk_curacc_on_task(p, MAY_WRITE, __func__);
 }
 
 /**
  * smack_task_getioprio - Smack check on reading ioprio
  * @p: the task object
  *
  * Return 0 if read access is permitted
  */
 static int smack_task_getioprio(struct task_struct *p)
 {
     return smk_curacc_on_task(p, MAY_READ, __func__);
 }
 
 /**
  * smack_task_setscheduler - Smack check on setting scheduler
  * @p: the task object
  *
  * Return 0 if read access is permitted
  */
 static int smack_task_setscheduler(struct task_struct *p)
 {
     return smk_curacc_on_task(p, MAY_WRITE, __func__);
 }
 
 /**
  * smack_task_getscheduler - Smack check on reading scheduler
  * @p: the task object
  *
  * Return 0 if read access is permitted
  */
 static int smack_task_getscheduler(struct task_struct *p)
 {
     return smk_curacc_on_task(p, MAY_READ, __func__);
 }
 
 /**
  * smack_task_movememory - Smack check on moving memory
  * @p: the task object
  *
  * Return 0 if write access is permitted
  */
 static int smack_task_movememory(struct task_struct *p)
 {
     return smk_curacc_on_task(p, MAY_WRITE, __func__);
 }
 
 /**
  * smack_task_kill - Smack check on signal delivery
  * @p: the task object
  * @info: unused
  * @sig: unused
  * @cred: identifies the cred to use in lieu of current's
  *
  * Return 0 if write access is permitted
  *
  */
 static int smack_task_kill(struct task_struct *p, struct kernel_siginfo *info,
                int sig, const struct cred *cred)
 {
     struct smk_audit_info ad;
     struct smack_known *skp;
     struct smack_known *tkp = smk_of_task_struct_obj(p);
     int rc;
 
     if (!sig)
         return 0; /* null signal; existence test */
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
     smk_ad_setfield_u_tsk(&ad, p);
     /*
      * Sending a signal requires that the sender
      * can write the receiver.
      */
     if (cred == NULL) {
         rc = smk_curacc(tkp, MAY_DELIVER, &ad);
         rc = smk_bu_task(p, MAY_DELIVER, rc);
         return rc;
     }
     /*
      * If the cred isn't NULL we're dealing with some USB IO
      * specific behavior. This is not clean. For one thing
      * we can't take privilege into account.
      */
     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;
 }
 
 /**
  * smack_task_to_inode - copy task smack into the inode blob
  * @p: task to copy from
  * @inode: inode to copy to
  *
  * Sets the smack pointer in the inode security blob
  */
 static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
 {
     struct inode_smack *isp = smack_inode(inode);
     struct smack_known *skp = smk_of_task_struct_obj(p);
 
     isp->smk_inode = skp;
     isp->smk_flags |= SMK_INODE_INSTANT;
 }
 
 /*
  * Socket hooks.
  */
 
 /**
  * smack_sk_alloc_security - Allocate a socket blob
  * @sk: the socket
  * @family: unused
  * @gfp_flags: memory allocation flags
  *
  * Assign Smack pointers to current
  *
  * Returns 0 on success, -ENOMEM is there's no memory
  */
 static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
 {
     struct smack_known *skp = smk_of_current();
     struct socket_smack *ssp;
 
     ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
     if (ssp == NULL)
         return -ENOMEM;
 
     /*
      * Sockets created by kernel threads receive web label.
      */
     if (unlikely(current->flags & PF_KTHREAD)) {
         ssp->smk_in = &smack_known_web;
         ssp->smk_out = &smack_known_web;
     } else {
         ssp->smk_in = skp;
         ssp->smk_out = skp;
     }
     ssp->smk_packet = NULL;
 
     sk->sk_security = ssp;
 
     return 0;
 }
 
 /**
  * smack_sk_free_security - Free a socket blob
  * @sk: the socket
  *
  * Clears the blob pointer
  */
 static void smack_sk_free_security(struct sock *sk)
 {
 #ifdef SMACK_IPV6_PORT_LABELING
     struct smk_port_label *spp;
 
     if (sk->sk_family == PF_INET6) {
         rcu_read_lock();
         list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
             if (spp->smk_sock != sk)
                 continue;
             spp->smk_can_reuse = 1;
             break;
         }
         rcu_read_unlock();
     }
 #endif
     kfree(sk->sk_security);
 }
 
 /**
 * smack_ipv4host_label - check host based restrictions
 * @sip: the object end
 *
 * looks for host based access restrictions
 *
 * This version will only be appropriate for really small sets of single label
 * hosts.  The caller is responsible for ensuring that the RCU read lock is
 * taken before calling this function.
 *
 * Returns the label of the far end or NULL if it's not special.
 */
 static struct smack_known *smack_ipv4host_label(struct sockaddr_in *sip)
 {
     struct smk_net4addr *snp;
     struct in_addr *siap = &sip->sin_addr;
 
     if (siap->s_addr == 0)
         return NULL;
 
     list_for_each_entry_rcu(snp, &smk_net4addr_list, list)
         /*
          * we break after finding the first match because
          * the list is sorted from longest to shortest mask
          * so we have found the most specific match
          */
         if (snp->smk_host.s_addr ==
             (siap->s_addr & snp->smk_mask.s_addr))
             return snp->smk_label;
 
     return NULL;
 }
 
 /*
  * smk_ipv6_localhost - Check for local ipv6 host address
  * @sip: the address
  *
  * Returns boolean true if this is the localhost address
  */
 static bool smk_ipv6_localhost(struct sockaddr_in6 *sip)
 {
     __be16 *be16p = (__be16 *)&sip->sin6_addr;
     __be32 *be32p = (__be32 *)&sip->sin6_addr;
 
     if (be32p[0] == 0 && be32p[1] == 0 && be32p[2] == 0 && be16p[6] == 0 &&
         ntohs(be16p[7]) == 1)
         return true;
     return false;
 }
 
 /**
 * smack_ipv6host_label - check host based restrictions
 * @sip: the object end
 *
 * looks for host based access restrictions
 *
 * This version will only be appropriate for really small sets of single label
 * hosts.  The caller is responsible for ensuring that the RCU read lock is
 * taken before calling this function.
 *
 * Returns the label of the far end or NULL if it's not special.
 */
 static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip)
 {
     struct smk_net6addr *snp;
     struct in6_addr *sap = &sip->sin6_addr;
     int i;
     int found = 0;
 
     /*
      * It's local. Don't look for a host label.
      */
     if (smk_ipv6_localhost(sip))
         return NULL;
 
     list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
         /*
          * If the label is NULL the entry has
          * been renounced. Ignore it.
          */
         if (snp->smk_label == NULL)
             continue;
         /*
         * we break after finding the first match because
         * the list is sorted from longest to shortest mask
         * so we have found the most specific match
         */
         for (found = 1, i = 0; i < 8; i++) {
             if ((sap->s6_addr16[i] & snp->smk_mask.s6_addr16[i]) !=
                 snp->smk_host.s6_addr16[i]) {
                 found = 0;
                 break;
             }
         }
         if (found)
             return snp->smk_label;
     }
 
     return NULL;
 }
 
 /**
  * smack_netlbl_add - Set the secattr on a socket
  * @sk: the socket
  *
  * Attach the outbound smack value (smk_out) to the socket.
  *
  * Returns 0 on success or an error code
  */
 static int smack_netlbl_add(struct sock *sk)
 {
     struct socket_smack *ssp = sk->sk_security;
     struct smack_known *skp = ssp->smk_out;
     int rc;
 
     local_bh_disable();
     bh_lock_sock_nested(sk);
 
     rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
     switch (rc) {
     case 0:
         ssp->smk_state = SMK_NETLBL_LABELED;
         break;
     case -EDESTADDRREQ:
         ssp->smk_state = SMK_NETLBL_REQSKB;
         rc = 0;
         break;
     }
 
     bh_unlock_sock(sk);
     local_bh_enable();
 
     return rc;
 }
 
 /**
  * smack_netlbl_delete - Remove the secattr from a socket
  * @sk: the socket
  *
  * Remove the outbound smack value from a socket
  */
 static void smack_netlbl_delete(struct sock *sk)
 {
     struct socket_smack *ssp = sk->sk_security;
 
     /*
      * Take the label off the socket if one is set.
      */
     if (ssp->smk_state != SMK_NETLBL_LABELED)
         return;
 
     local_bh_disable();
     bh_lock_sock_nested(sk);
     netlbl_sock_delattr(sk);
     bh_unlock_sock(sk);
     local_bh_enable();
     ssp->smk_state = SMK_NETLBL_UNLABELED;
 }
 
 /**
  * smk_ipv4_check - Perform IPv4 host access checks
  * @sk: the socket
  * @sap: the destination address
  *
  * Set the correct secattr for the given socket based on the destination
  * address and perform any outbound access checks needed.
  *
  * Returns 0 on success or an error code.
  *
  */
 static int smk_ipv4_check(struct sock *sk, struct sockaddr_in *sap)
 {
     struct smack_known *skp;
     int rc = 0;
     struct smack_known *hkp;
     struct socket_smack *ssp = sk->sk_security;
     struct smk_audit_info ad;
 
     rcu_read_lock();
     hkp = smack_ipv4host_label(sap);
     if (hkp != NULL) {
 #ifdef CONFIG_AUDIT
         struct lsm_network_audit net;
 
         smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
         ad.a.u.net->family = sap->sin_family;
         ad.a.u.net->dport = sap->sin_port;
         ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
 #endif
         skp = ssp->smk_out;
         rc = smk_access(skp, hkp, MAY_WRITE, &ad);
         rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc);
         /*
          * Clear the socket netlabel if it's set.
          */
         if (!rc)
             smack_netlbl_delete(sk);
     }
     rcu_read_unlock();
 
     return rc;
 }
 
 /**
  * smk_ipv6_check - check Smack access
  * @subject: subject Smack label
  * @object: object Smack label
  * @address: address
  * @act: the action being taken
  *
  * Check an IPv6 access
  */
 static int smk_ipv6_check(struct smack_known *subject,
                 struct smack_known *object,
                 struct sockaddr_in6 *address, int act)
 {
 #ifdef CONFIG_AUDIT
     struct lsm_network_audit net;
 #endif
     struct smk_audit_info ad;
     int rc;
 
 #ifdef CONFIG_AUDIT
     smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
     ad.a.u.net->family = PF_INET6;
     ad.a.u.net->dport = address->sin6_port;
     if (act == SMK_RECEIVING)
         ad.a.u.net->v6info.saddr = address->sin6_addr;
     else
         ad.a.u.net->v6info.daddr = address->sin6_addr;
 #endif
     rc = smk_access(subject, object, MAY_WRITE, &ad);
     rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc);
     return rc;
 }
 
 #ifdef SMACK_IPV6_PORT_LABELING
 /**
  * smk_ipv6_port_label - Smack port access table management
  * @sock: socket
  * @address: address
  *
  * Create or update the port list entry
  */
 static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
 {
     struct sock *sk = sock->sk;
     struct sockaddr_in6 *addr6;
     struct socket_smack *ssp = sock->sk->sk_security;
     struct smk_port_label *spp;
     unsigned short port = 0;
 
     if (address == NULL) {
         /*
          * This operation is changing the Smack information
          * on the bound socket. Take the changes to the port
          * as well.
          */
         rcu_read_lock();
         list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
             if (sk != spp->smk_sock)
                 continue;
             spp->smk_in = ssp->smk_in;
             spp->smk_out = ssp->smk_out;
             rcu_read_unlock();
             return;
         }
         /*
          * A NULL address is only used for updating existing
          * bound entries. If there isn't one, it's OK.
          */
         rcu_read_unlock();
         return;
     }
 
     addr6 = (struct sockaddr_in6 *)address;
     port = ntohs(addr6->sin6_port);
     /*
      * This is a special case that is safely ignored.
      */
     if (port == 0)
         return;
 
     /*
      * Look for an existing port list entry.
      * This is an indication that a port is getting reused.
      */
     rcu_read_lock();
     list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
         if (spp->smk_port != port || spp->smk_sock_type != sock->type)
             continue;
         if (spp->smk_can_reuse != 1) {
             rcu_read_unlock();
             return;
         }
         spp->smk_port = port;
         spp->smk_sock = sk;
         spp->smk_in = ssp->smk_in;
         spp->smk_out = ssp->smk_out;
         spp->smk_can_reuse = 0;
         rcu_read_unlock();
         return;
     }
     rcu_read_unlock();
     /*
      * A new port entry is required.
      */
     spp = kzalloc(sizeof(*spp), GFP_KERNEL);
     if (spp == NULL)
         return;
 
     spp->smk_port = port;
     spp->smk_sock = sk;
     spp->smk_in = ssp->smk_in;
     spp->smk_out = ssp->smk_out;
     spp->smk_sock_type = sock->type;
     spp->smk_can_reuse = 0;
 
     mutex_lock(&smack_ipv6_lock);
     list_add_rcu(&spp->list, &smk_ipv6_port_list);
     mutex_unlock(&smack_ipv6_lock);
     return;
 }
 
 /**
  * smk_ipv6_port_check - check Smack port access
  * @sk: socket
  * @address: address
  * @act: the action being taken
  *
  * Create or update the port list entry
  */
 static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
                 int act)
 {
     struct smk_port_label *spp;
     struct socket_smack *ssp = sk->sk_security;
     struct smack_known *skp = NULL;
     unsigned short port;
     struct smack_known *object;
 
     if (act == SMK_RECEIVING) {
         skp = smack_ipv6host_label(address);
         object = ssp->smk_in;
     } else {
         skp = ssp->smk_out;
         object = smack_ipv6host_label(address);
     }
 
     /*
      * The other end is a single label host.
      */
     if (skp != NULL && object != NULL)
         return smk_ipv6_check(skp, object, address, act);
     if (skp == NULL)
         skp = smack_net_ambient;
     if (object == NULL)
         object = smack_net_ambient;
 
     /*
      * It's remote, so port lookup does no good.
      */
     if (!smk_ipv6_localhost(address))
         return smk_ipv6_check(skp, object, address, act);
 
     /*
      * It's local so the send check has to have passed.
      */
     if (act == SMK_RECEIVING)
         return 0;
 
     port = ntohs(address->sin6_port);
     rcu_read_lock();
     list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
         if (spp->smk_port != port || spp->smk_sock_type != sk->sk_type)
             continue;
         object = spp->smk_in;
         if (act == SMK_CONNECTING)
             ssp->smk_packet = spp->smk_out;
         break;
     }
     rcu_read_unlock();
 
     return smk_ipv6_check(skp, object, address, act);
 }
 #endif
 
 /**
  * smack_inode_setsecurity - set smack xattrs
  * @inode: the object
  * @name: attribute name
  * @value: attribute value
  * @size: size of the attribute
  * @flags: unused
  *
  * Sets the named attribute in the appropriate blob
  *
  * Returns 0 on success, or an error code
  */
 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 = smack_inode(inode);
     struct socket_smack *ssp;
     struct socket *sock;
     int rc = 0;
 
     if (value == NULL || size > SMK_LONGLABEL || size == 0)
         return -EINVAL;
 
     skp = smk_import_entry(value, size);
     if (IS_ERR(skp))
         return PTR_ERR(skp);
 
     if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
         nsp->smk_inode = skp;
         nsp->smk_flags |= SMK_INODE_INSTANT;
         return 0;
     }
     /*
      * The rest of the Smack xattrs are only on sockets.
      */
     if (inode->i_sb->s_magic != SOCKFS_MAGIC)
         return -EOPNOTSUPP;
 
     sock = SOCKET_I(inode);
     if (sock == NULL || sock->sk == NULL)
         return -EOPNOTSUPP;
 
     ssp = sock->sk->sk_security;
 
     if (strcmp(name, XATTR_SMACK_IPIN) == 0)
         ssp->smk_in = skp;
     else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
         ssp->smk_out = skp;
         if (sock->sk->sk_family == PF_INET) {
             rc = smack_netlbl_add(sock->sk);
             if (rc != 0)
                 printk(KERN_WARNING
                     "Smack: \"%s\" netlbl error %d.\n",
                     __func__, -rc);
         }
     } else
         return -EOPNOTSUPP;
 
 #ifdef SMACK_IPV6_PORT_LABELING
     if (sock->sk->sk_family == PF_INET6)
         smk_ipv6_port_label(sock, NULL);
 #endif
 
     return 0;
 }
 
 /**
  * smack_socket_post_create - finish socket setup
  * @sock: the socket
  * @family: protocol family
  * @type: unused
  * @protocol: unused
  * @kern: unused
  *
  * Sets the netlabel information on the socket
  *
  * Returns 0 on success, and error code otherwise
  */
 static int smack_socket_post_create(struct socket *sock, int family,
                     int type, int protocol, int kern)
 {
     struct socket_smack *ssp;
 
     if (sock->sk == NULL)
         return 0;
 
     /*
      * Sockets created by kernel threads receive web label.
      */
     if (unlikely(current->flags & PF_KTHREAD)) {
         ssp = sock->sk->sk_security;
         ssp->smk_in = &smack_known_web;
         ssp->smk_out = &smack_known_web;
     }
 
     if (family != PF_INET)
         return 0;
     /*
      * Set the outbound netlbl.
      */
     return smack_netlbl_add(sock->sk);
 }
 
 /**
  * smack_socket_socketpair - create socket pair
  * @socka: one socket
  * @sockb: another socket
  *
  * Cross reference the peer labels for SO_PEERSEC
  *
  * Returns 0
  */
 static int smack_socket_socketpair(struct socket *socka,
                            struct socket *sockb)
 {
     struct socket_smack *asp = socka->sk->sk_security;
     struct socket_smack *bsp = sockb->sk->sk_security;
 
     asp->smk_packet = bsp->smk_out;
     bsp->smk_packet = asp->smk_out;
 
     return 0;
 }
 
 #ifdef SMACK_IPV6_PORT_LABELING
 /**
  * smack_socket_bind - record port binding information.
  * @sock: the socket
  * @address: the port address
  * @addrlen: size of the address
  *
  * Records the label bound to a port.
  *
  * Returns 0 on success, and error code otherwise
  */
 static int smack_socket_bind(struct socket *sock, struct sockaddr *address,
                 int addrlen)
 {
     if (sock->sk != NULL && sock->sk->sk_family == PF_INET6) {
         if (addrlen < SIN6_LEN_RFC2133 ||
             address->sa_family != AF_INET6)
             return -EINVAL;
         smk_ipv6_port_label(sock, address);
     }
     return 0;
 }
 #endif /* SMACK_IPV6_PORT_LABELING */
 
 /**
  * smack_socket_connect - connect access check
  * @sock: the socket
  * @sap: the other end
  * @addrlen: size of sap
  *
  * Verifies that a connection may be possible
  *
  * Returns 0 on success, and error code otherwise
  */
 static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
                 int addrlen)
 {
     int rc = 0;
 
     if (sock->sk == NULL)
         return 0;
     if (sock->sk->sk_family != PF_INET &&
         (!IS_ENABLED(CONFIG_IPV6) || sock->sk->sk_family != PF_INET6))
         return 0;
     if (addrlen < offsetofend(struct sockaddr, sa_family))
         return 0;
     if (IS_ENABLED(CONFIG_IPV6) && sap->sa_family == AF_INET6) {
         struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;
         struct smack_known *rsp = NULL;
 
         if (addrlen < SIN6_LEN_RFC2133)
             return 0;
         if (__is_defined(SMACK_IPV6_SECMARK_LABELING))
             rsp = smack_ipv6host_label(sip);
         if (rsp != NULL) {
             struct socket_smack *ssp = sock->sk->sk_security;
 
             rc = smk_ipv6_check(ssp->smk_out, rsp, sip,
                         SMK_CONNECTING);
         }
 #ifdef SMACK_IPV6_PORT_LABELING
         rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
 #endif
 
         return rc;
     }
     if (sap->sa_family != AF_INET || addrlen < sizeof(struct sockaddr_in))
         return 0;
     rc = smk_ipv4_check(sock->sk, (struct sockaddr_in *)sap);
     return rc;
 }
 
 /**
  * smack_flags_to_may - convert S_ to MAY_ values
  * @flags: the S_ value
  *
  * Returns the equivalent MAY_ value
  */
 static int smack_flags_to_may(int flags)
 {
     int may = 0;
 
     if (flags & S_IRUGO)
         may |= MAY_READ;
     if (flags & S_IWUGO)
         may |= MAY_WRITE;
     if (flags & S_IXUGO)
         may |= MAY_EXEC;
 
     return may;
 }
 
 /**
  * smack_msg_msg_alloc_security - Set the security blob for msg_msg
  * @msg: the object
  *
  * Returns 0
  */
 static int smack_msg_msg_alloc_security(struct msg_msg *msg)
 {
     struct smack_known **blob = smack_msg_msg(msg);
 
     *blob = smk_of_current();
     return 0;
 }
 
 /**
  * smack_of_ipc - the smack pointer for the ipc
  * @isp: the object
  *
  * Returns a pointer to the smack value
  */
 static struct smack_known *smack_of_ipc(struct kern_ipc_perm *isp)
 {
     struct smack_known **blob = smack_ipc(isp);
 
     return *blob;
 }
 
 /**
  * smack_ipc_alloc_security - Set the security blob for ipc
  * @isp: the object
  *
  * Returns 0
  */
 static int smack_ipc_alloc_security(struct kern_ipc_perm *isp)
 {
     struct smack_known **blob = smack_ipc(isp);
 
     *blob = smk_of_current();
     return 0;
 }
 
 /**
  * smk_curacc_shm : check if current has access on shm
  * @isp : the object
  * @access : access requested
  *
  * Returns 0 if current has the requested access, error code otherwise
  */
 static int smk_curacc_shm(struct kern_ipc_perm *isp, int access)
 {
     struct smack_known *ssp = smack_of_ipc(isp);
     struct smk_audit_info ad;
     int rc;
 
 #ifdef CONFIG_AUDIT
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
     ad.a.u.ipc_id = isp->id;
 #endif
     rc = smk_curacc(ssp, access, &ad);
     rc = smk_bu_current("shm", ssp, access, rc);
     return rc;
 }
 
 /**
  * smack_shm_associate - Smack access check for shm
  * @isp: the object
  * @shmflg: access requested
  *
  * Returns 0 if current has the requested access, error code otherwise
  */
 static int smack_shm_associate(struct kern_ipc_perm *isp, int shmflg)
 {
     int may;
 
     may = smack_flags_to_may(shmflg);
     return smk_curacc_shm(isp, may);
 }
 
 /**
  * smack_shm_shmctl - Smack access check for shm
  * @isp: the object
  * @cmd: what it wants to do
  *
  * Returns 0 if current has the requested access, error code otherwise
  */
 static int smack_shm_shmctl(struct kern_ipc_perm *isp, int cmd)
 {
     int may;
 
     switch (cmd) {
     case IPC_STAT:
     case SHM_STAT:
     case SHM_STAT_ANY:
         may = MAY_READ;
         break;
     case IPC_SET:
     case SHM_LOCK:
     case SHM_UNLOCK:
     case IPC_RMID:
         may = MAY_READWRITE;
         break;
     case IPC_INFO:
     case SHM_INFO:
         /*
          * System level information.
          */
         return 0;
     default:
         return -EINVAL;
     }
     return smk_curacc_shm(isp, may);
 }
 
 /**
  * smack_shm_shmat - Smack access for shmat
  * @isp: the object
  * @shmaddr: unused
  * @shmflg: access requested
  *
  * Returns 0 if current has the requested access, error code otherwise
  */
 static int smack_shm_shmat(struct kern_ipc_perm *isp, char __user *shmaddr,
                int shmflg)
 {
     int may;
 
     may = smack_flags_to_may(shmflg);
     return smk_curacc_shm(isp, may);
 }
 
 /**
  * smk_curacc_sem : check if current has access on sem
  * @isp : the object
  * @access : access requested
  *
  * Returns 0 if current has the requested access, error code otherwise
  */
 static int smk_curacc_sem(struct kern_ipc_perm *isp, int access)
 {
     struct smack_known *ssp = smack_of_ipc(isp);
     struct smk_audit_info ad;
     int rc;
 
 #ifdef CONFIG_AUDIT
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
     ad.a.u.ipc_id = isp->id;
 #endif
     rc = smk_curacc(ssp, access, &ad);
     rc = smk_bu_current("sem", ssp, access, rc);
     return rc;
 }
 
 /**
  * smack_sem_associate - Smack access check for sem
  * @isp: the object
  * @semflg: access requested
  *
  * Returns 0 if current has the requested access, error code otherwise
  */
 static int smack_sem_associate(struct kern_ipc_perm *isp, int semflg)
 {
     int may;
 
     may = smack_flags_to_may(semflg);
     return smk_curacc_sem(isp, may);
 }
 
 /**
  * smack_sem_semctl - Smack access check for sem
  * @isp: the object
  * @cmd: what it wants to do
  *
  * Returns 0 if current has the requested access, error code otherwise
  */
 static int smack_sem_semctl(struct kern_ipc_perm *isp, int cmd)
 {
     int may;
 
     switch (cmd) {
     case GETPID:
     case GETNCNT:
     case GETZCNT:
     case GETVAL:
     case GETALL:
     case IPC_STAT:
     case SEM_STAT:
     case SEM_STAT_ANY:
         may = MAY_READ;
         break;
     case SETVAL:
     case SETALL:
     case IPC_RMID:
     case IPC_SET:
         may = MAY_READWRITE;
         break;
     case IPC_INFO:
     case SEM_INFO:
         /*
          * System level information
          */
         return 0;
     default:
         return -EINVAL;
     }
 
     return smk_curacc_sem(isp, may);
 }
 
 /**
  * smack_sem_semop - Smack checks of semaphore operations
  * @isp: the object
  * @sops: unused
  * @nsops: unused
  * @alter: unused
  *
  * Treated as read and write in all cases.
  *
  * Returns 0 if access is allowed, error code otherwise
  */
 static int smack_sem_semop(struct kern_ipc_perm *isp, struct sembuf *sops,
                unsigned nsops, int alter)
 {
     return smk_curacc_sem(isp, MAY_READWRITE);
 }
 
 /**
  * smk_curacc_msq : helper to check if current has access on msq
  * @isp : the msq
  * @access : access requested
  *
  * return 0 if current has access, error otherwise
  */
 static int smk_curacc_msq(struct kern_ipc_perm *isp, int access)
 {
     struct smack_known *msp = smack_of_ipc(isp);
     struct smk_audit_info ad;
     int rc;
 
 #ifdef CONFIG_AUDIT
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
     ad.a.u.ipc_id = isp->id;
 #endif
     rc = smk_curacc(msp, access, &ad);
     rc = smk_bu_current("msq", msp, access, rc);
     return rc;
 }
 
 /**
  * smack_msg_queue_associate - Smack access check for msg_queue
  * @isp: the object
  * @msqflg: access requested
  *
  * Returns 0 if current has the requested access, error code otherwise
  */
 static int smack_msg_queue_associate(struct kern_ipc_perm *isp, int msqflg)
 {
     int may;
 
     may = smack_flags_to_may(msqflg);
     return smk_curacc_msq(isp, may);
 }
 
 /**
  * smack_msg_queue_msgctl - Smack access check for msg_queue
  * @isp: the object
  * @cmd: what it wants to do
  *
  * Returns 0 if current has the requested access, error code otherwise
  */
 static int smack_msg_queue_msgctl(struct kern_ipc_perm *isp, int cmd)
 {
     int may;
 
     switch (cmd) {
     case IPC_STAT:
     case MSG_STAT:
     case MSG_STAT_ANY:
         may = MAY_READ;
         break;
     case IPC_SET:
     case IPC_RMID:
         may = MAY_READWRITE;
         break;
     case IPC_INFO:
     case MSG_INFO:
         /*
          * System level information
          */
         return 0;
     default:
         return -EINVAL;
     }
 
     return smk_curacc_msq(isp, may);
 }
 
 /**
  * smack_msg_queue_msgsnd - Smack access check for msg_queue
  * @isp: the object
  * @msg: unused
  * @msqflg: access requested
  *
  * Returns 0 if current has the requested access, error code otherwise
  */
 static int smack_msg_queue_msgsnd(struct kern_ipc_perm *isp, struct msg_msg *msg,
                   int msqflg)
 {
     int may;
 
     may = smack_flags_to_may(msqflg);
     return smk_curacc_msq(isp, may);
 }
 
 /**
  * smack_msg_queue_msgrcv - Smack access check for msg_queue
  * @isp: the object
  * @msg: unused
  * @target: unused
  * @type: unused
  * @mode: unused
  *
  * Returns 0 if current has read and write access, error code otherwise
  */
 static int smack_msg_queue_msgrcv(struct kern_ipc_perm *isp,
                   struct msg_msg *msg,
                   struct task_struct *target, long type,
                   int mode)
 {
     return smk_curacc_msq(isp, MAY_READWRITE);
 }
 
 /**
  * smack_ipc_permission - Smack access for ipc_permission()
  * @ipp: the object permissions
  * @flag: access requested
  *
  * Returns 0 if current has read and write access, error code otherwise
  */
 static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
 {
     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;
 
 #ifdef CONFIG_AUDIT
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
     ad.a.u.ipc_id = ipp->id;
 #endif
     rc = smk_curacc(iskp, may, &ad);
     rc = smk_bu_current("svipc", iskp, may, rc);
     return rc;
 }
 
 /**
  * smack_ipc_getsecid - Extract smack security id
  * @ipp: the object permissions
  * @secid: where result will be saved
  */
 static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
 {
     struct smack_known **blob = smack_ipc(ipp);
     struct smack_known *iskp = *blob;
 
     *secid = iskp->smk_secid;
 }
 
 /**
  * smack_d_instantiate - Make sure the blob is correct on an inode
  * @opt_dentry: dentry where inode will be attached
  * @inode: the object
  *
  * Set the inode's security blob if it hasn't been done already.
  */
 static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
 {
     struct super_block *sbp;
     struct superblock_smack *sbsp;
     struct inode_smack *isp;
     struct smack_known *skp;
     struct smack_known *ckp = smk_of_current();
     struct smack_known *final;
     char trattr[TRANS_TRUE_SIZE];
     int transflag = 0;
     int rc;
     struct dentry *dp;
 
     if (inode == NULL)
         return;
 
     isp = smack_inode(inode);
 
     /*
      * If the inode is already instantiated
      * take the quick way out
      */
     if (isp->smk_flags & SMK_INODE_INSTANT)
         return;
 
     sbp = inode->i_sb;
     sbsp = smack_superblock(sbp);
     /*
      * We're going to use the superblock default label
      * if there's no label on the file.
      */
     final = sbsp->smk_default;
 
     /*
      * If this is the root inode the superblock
      * may be in the process of initialization.
      * If that is the case use the root value out
      * of the superblock.
      */
     if (opt_dentry->d_parent == opt_dentry) {
         switch (sbp->s_magic) {
         case CGROUP_SUPER_MAGIC:
         case CGROUP2_SUPER_MAGIC:
             /*
              * The cgroup filesystem is never mounted,
              * so there's no opportunity to set the mount
              * options.
              */
             sbsp->smk_root = &smack_known_star;
             sbsp->smk_default = &smack_known_star;
             isp->smk_inode = sbsp->smk_root;
             break;
         case TMPFS_MAGIC:
             /*
              * What about shmem/tmpfs anonymous files with dentry
              * obtained from d_alloc_pseudo()?
              */
             isp->smk_inode = smk_of_current();
             break;
         case PIPEFS_MAGIC:
             isp->smk_inode = smk_of_current();
             break;
         case SOCKFS_MAGIC:
             /*
              * Socket access is controlled by the socket
              * structures associated with the task involved.
              */
             isp->smk_inode = &smack_known_star;
             break;
         default:
             isp->smk_inode = sbsp->smk_root;
             break;
         }
         isp->smk_flags |= SMK_INODE_INSTANT;
         return;
     }
 
     /*
      * This is pretty hackish.
      * Casey says that we shouldn't have to do
      * file system specific code, but it does help
      * with keeping it simple.
      */
     switch (sbp->s_magic) {
     case SMACK_MAGIC:
     case CGROUP_SUPER_MAGIC:
     case CGROUP2_SUPER_MAGIC:
         /*
          * Casey says that it's a little embarrassing
          * that the smack file system doesn't do
          * extended attributes.
          *
          * Cgroupfs is special
          */
         final = &smack_known_star;
         break;
     case DEVPTS_SUPER_MAGIC:
         /*
          * devpts seems content with the label of the task.
          * Programs that change smack have to treat the
          * pty with respect.
          */
         final = ckp;
         break;
     case PROC_SUPER_MAGIC:
         /*
          * Casey says procfs appears not to care.
          * The superblock default suffices.
          */
         break;
     case TMPFS_MAGIC:
         /*
          * Device labels should come from the filesystem,
          * but watch out, because they're volitile,
          * getting recreated on every reboot.
          */
         final = &smack_known_star;
         /*
          * If a smack value has been set we want to use it,
          * but since tmpfs isn't giving us the opportunity
          * to set mount options simulate setting the
          * superblock default.
          */
         fallthrough;
     default:
         /*
          * This isn't an understood special case.
          * Get the value from the xattr.
          */
 
         /*
          * UNIX domain sockets use lower level socket data.
          */
         if (S_ISSOCK(inode->i_mode)) {
             final = &smack_known_star;
             break;
         }
         /*
          * No xattr support means, alas, no SMACK label.
          * Use the aforeapplied default.
          * It would be curious if the label of the task
          * does not match that assigned.
          */
         if (!(inode->i_opflags & IOP_XATTR))
                 break;
         /*
          * Get the dentry for xattr.
          */
         dp = dget(opt_dentry);
         skp = smk_fetch(XATTR_NAME_SMACK, inode, dp);
         if (!IS_ERR_OR_NULL(skp))
             final = skp;
 
         /*
          * Transmuting directory
          */
         if (S_ISDIR(inode->i_mode)) {
             /*
              * If this is a new directory and the label was
              * transmuted when the inode was initialized
              * set the transmute attribute on the directory
              * and mark the inode.
              *
              * If there is a transmute attribute on the
              * directory mark the inode.
              */
             if (isp->smk_flags & SMK_INODE_CHANGED) {
                 isp->smk_flags &= ~SMK_INODE_CHANGED;
                 rc = __vfs_setxattr(&init_user_ns, dp, inode,
                     XATTR_NAME_SMACKTRANSMUTE,
                     TRANS_TRUE, TRANS_TRUE_SIZE,
                     0);
             } else {
                 rc = __vfs_getxattr(dp, inode,
                     XATTR_NAME_SMACKTRANSMUTE, trattr,
                     TRANS_TRUE_SIZE);
                 if (rc >= 0 && strncmp(trattr, TRANS_TRUE,
                                TRANS_TRUE_SIZE) != 0)
                     rc = -EINVAL;
             }
             if (rc >= 0)
                 transflag = SMK_INODE_TRANSMUTE;
         }
         /*
          * Don't let the exec or mmap label be "*" or "@".
          */
         skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
         if (IS_ERR(skp) || skp == &smack_known_star ||
             skp == &smack_known_web)
             skp = NULL;
         isp->smk_task = skp;
 
         skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
         if (IS_ERR(skp) || skp == &smack_known_star ||
             skp == &smack_known_web)
             skp = NULL;
         isp->smk_mmap = skp;
 
         dput(dp);
         break;
     }
 
     if (final == NULL)
         isp->smk_inode = ckp;
     else
         isp->smk_inode = final;
 
     isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
 
     return;
 }
 
 /**
  * smack_getprocattr - Smack process attribute access
  * @p: the object task
  * @name: the name of the attribute in /proc/.../attr
  * @value: where to put the result
  *
  * Places a copy of the task Smack into value
  *
  * Returns the length of the smack label or an error code
  */
 static int smack_getprocattr(struct task_struct *p, char *name, char **value)
 {
     struct smack_known *skp = smk_of_task_struct_obj(p);
     char *cp;
     int slen;
 
     if (strcmp(name, "current") != 0)
         return -EINVAL;
 
     cp = kstrdup(skp->smk_known, GFP_KERNEL);
     if (cp == NULL)
         return -ENOMEM;
 
     slen = strlen(cp);
     *value = cp;
     return slen;
 }
 
 /**
  * smack_setprocattr - Smack process attribute setting
  * @name: the name of the attribute in /proc/.../attr
  * @value: the value to set
  * @size: the size of the value
  *
  * Sets the Smack value of the task. Only setting self
  * is permitted and only with privilege
  *
  * Returns the length of the smack label or an error code
  */
 static int smack_setprocattr(const char *name, void *value, size_t size)
 {
     struct task_smack *tsp = smack_cred(current_cred());
     struct cred *new;
     struct smack_known *skp;
     struct smack_known_list_elem *sklep;
     int rc;
 
     if (!smack_privileged(CAP_MAC_ADMIN) && list_empty(&tsp->smk_relabel))
         return -EPERM;
 
     if (value == NULL || size == 0 || size >= SMK_LONGLABEL)
         return -EINVAL;
 
     if (strcmp(name, "current") != 0)
         return -EINVAL;
 
     skp = smk_import_entry(value, size);
     if (IS_ERR(skp))
         return PTR_ERR(skp);
 
     /*
      * No process is ever allowed the web ("@") label
      * and the star ("*") label.
      */
     if (skp == &smack_known_web || skp == &smack_known_star)
         return -EINVAL;
 
     if (!smack_privileged(CAP_MAC_ADMIN)) {
         rc = -EPERM;
         list_for_each_entry(sklep, &tsp->smk_relabel, list)
             if (sklep->smk_label == skp) {
                 rc = 0;
                 break;
             }
         if (rc)
             return rc;
     }
 
     new = prepare_creds();
     if (new == NULL)
         return -ENOMEM;
 
     tsp = smack_cred(new);
     tsp->smk_task = skp;
     /*
      * process can change its label only once
      */
     smk_destroy_label_list(&tsp->smk_relabel);
 
     commit_creds(new);
     return size;
 }
 
 /**
  * smack_unix_stream_connect - Smack access on UDS
  * @sock: one sock
  * @other: the other sock
  * @newsk: unused
  *
  * Return 0 if a subject with the smack of sock could access
  * an object with the smack of other, otherwise an error code
  */
 static int smack_unix_stream_connect(struct sock *sock,
                      struct sock *other, struct sock *newsk)
 {
     struct smack_known *skp;
     struct smack_known *okp;
     struct socket_smack *ssp = sock->sk_security;
     struct socket_smack *osp = other->sk_security;
     struct socket_smack *nsp = newsk->sk_security;
     struct smk_audit_info ad;
     int rc = 0;
 #ifdef CONFIG_AUDIT
     struct lsm_network_audit net;
 #endif
 
     if (!smack_privileged(CAP_MAC_OVERRIDE)) {
         skp = ssp->smk_out;
         okp = osp->smk_in;
 #ifdef CONFIG_AUDIT
         smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
         smk_ad_setfield_u_net_sk(&ad, other);
 #endif
         rc = smk_access(skp, okp, MAY_WRITE, &ad);
         rc = smk_bu_note("UDS connect", skp, okp, MAY_WRITE, rc);
         if (rc == 0) {
             okp = osp->smk_out;
             skp = ssp->smk_in;
             rc = smk_access(okp, skp, MAY_WRITE, &ad);
             rc = smk_bu_note("UDS connect", okp, skp,
                         MAY_WRITE, rc);
         }
     }
 
     /*
      * Cross reference the peer labels for SO_PEERSEC.
      */
     if (rc == 0) {
         nsp->smk_packet = ssp->smk_out;
         ssp->smk_packet = osp->smk_out;
     }
 
     return rc;
 }
 
 /**
  * smack_unix_may_send - Smack access on UDS
  * @sock: one socket
  * @other: the other socket
  *
  * Return 0 if a subject with the smack of sock could access
  * an object with the smack of other, otherwise an error code
  */
 static int smack_unix_may_send(struct socket *sock, struct socket *other)
 {
     struct socket_smack *ssp = sock->sk->sk_security;
     struct socket_smack *osp = other->sk->sk_security;
     struct smk_audit_info ad;
     int rc;
 
 #ifdef CONFIG_AUDIT
     struct lsm_network_audit net;
 
     smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
     smk_ad_setfield_u_net_sk(&ad, other->sk);
 #endif
 
     if (smack_privileged(CAP_MAC_OVERRIDE))
         return 0;
 
     rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
     rc = smk_bu_note("UDS send", ssp->smk_out, osp->smk_in, MAY_WRITE, rc);
     return rc;
 }
 
 /**
  * smack_socket_sendmsg - Smack check based on destination host
  * @sock: the socket
  * @msg: the message
  * @size: the size of the message
  *
  * Return 0 if the current subject can write to the destination host.
  * For IPv4 this is only a question if the destination is a single label host.
  * For IPv6 this is a check against the label of the port.
  */
 static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
                 int size)
 {
     struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
 #if IS_ENABLED(CONFIG_IPV6)
     struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name;
 #endif
 #ifdef SMACK_IPV6_SECMARK_LABELING
     struct socket_smack *ssp = sock->sk->sk_security;
     struct smack_known *rsp;
 #endif
     int rc = 0;
 
     /*
      * Perfectly reasonable for this to be NULL
      */
     if (sip == NULL)
         return 0;
 
     switch (sock->sk->sk_family) {
     case AF_INET:
         if (msg->msg_namelen < sizeof(struct sockaddr_in) ||
             sip->sin_family != AF_INET)
             return -EINVAL;
         rc = smk_ipv4_check(sock->sk, sip);
         break;
 #if IS_ENABLED(CONFIG_IPV6)
     case AF_INET6:
         if (msg->msg_namelen < SIN6_LEN_RFC2133 ||
             sap->sin6_family != AF_INET6)
             return -EINVAL;
 #ifdef SMACK_IPV6_SECMARK_LABELING
         rsp = smack_ipv6host_label(sap);
         if (rsp != NULL)
             rc = smk_ipv6_check(ssp->smk_out, rsp, sap,
                         SMK_CONNECTING);
 #endif
 #ifdef SMACK_IPV6_PORT_LABELING
         rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING);
 #endif
 #endif /* IS_ENABLED(CONFIG_IPV6) */
         break;
     }
     return rc;
 }
 
 /**
  * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
  * @sap: netlabel secattr
  * @ssp: socket security information
  *
  * Returns a pointer to a Smack label entry found on the label list.
  */
 static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
                         struct socket_smack *ssp)
 {
     struct smack_known *skp;
     int found = 0;
     int acat;
     int kcat;
 
     /*
      * Netlabel found it in the cache.
      */
     if ((sap->flags & NETLBL_SECATTR_CACHE) != 0)
         return (struct smack_known *)sap->cache->data;
 
     if ((sap->flags & NETLBL_SECATTR_SECID) != 0)
         /*
          * Looks like a fallback, which gives us a secid.
          */
         return smack_from_secid(sap->attr.secid);
 
     if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
         /*
          * Looks like a CIPSO packet.
          * If there are flags but no level netlabel isn't
          * behaving the way we expect it to.
          *
          * Look it up in the label table
          * Without guidance regarding the smack value
          * for the packet fall back on the network
          * ambient value.
          */
         rcu_read_lock();
         list_for_each_entry_rcu(skp, &smack_known_list, list) {
             if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl)
                 continue;
             /*
              * Compare the catsets. Use the netlbl APIs.
              */
             if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) {
                 if ((skp->smk_netlabel.flags &
                      NETLBL_SECATTR_MLS_CAT) == 0)
                     found = 1;
                 break;
             }
             for (acat = -1, kcat = -1; acat == kcat; ) {
                 acat = netlbl_catmap_walk(sap->attr.mls.cat,
                               acat + 1);
                 kcat = netlbl_catmap_walk(
                     skp->smk_netlabel.attr.mls.cat,
                     kcat + 1);
                 if (acat < 0 || kcat < 0)
                     break;
             }
             if (acat == kcat) {
                 found = 1;
                 break;
             }
         }
         rcu_read_unlock();
 
         if (found)
             return skp;
 
         if (ssp != NULL && ssp->smk_in == &smack_known_star)
             return &smack_known_web;
         return &smack_known_star;
     }
     /*
      * Without guidance regarding the smack value
      * for the packet fall back on the network
      * ambient value.
      */
     return smack_net_ambient;
 }
 
 #if IS_ENABLED(CONFIG_IPV6)
 static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
 {
     u8 nexthdr;
     int offset;
     int proto = -EINVAL;
     struct ipv6hdr _ipv6h;
     struct ipv6hdr *ip6;
     __be16 frag_off;
     struct tcphdr _tcph, *th;
     struct udphdr _udph, *uh;
     struct dccp_hdr _dccph, *dh;
 
     sip->sin6_port = 0;
 
     offset = skb_network_offset(skb);
     ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
     if (ip6 == NULL)
         return -EINVAL;
     sip->sin6_addr = ip6->saddr;
 
     nexthdr = ip6->nexthdr;
     offset += sizeof(_ipv6h);
     offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
     if (offset < 0)
         return -EINVAL;
 
     proto = nexthdr;
     switch (proto) {
     case IPPROTO_TCP:
         th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
         if (th != NULL)
             sip->sin6_port = th->source;
         break;
     case IPPROTO_UDP:
     case IPPROTO_UDPLITE:
         uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
         if (uh != NULL)
             sip->sin6_port = uh->source;
         break;
     case IPPROTO_DCCP:
         dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
         if (dh != NULL)
             sip->sin6_port = dh->dccph_sport;
         break;
     }
     return proto;
 }
 #endif /* CONFIG_IPV6 */
 
 /**
  * smack_from_skb - Smack data from the secmark in an skb
  * @skb: packet
  *
  * Returns smack_known of the secmark or NULL if that won't work.
  */
 #ifdef CONFIG_NETWORK_SECMARK
 static struct smack_known *smack_from_skb(struct sk_buff *skb)
 {
     if (skb == NULL || skb->secmark == 0)
         return NULL;
 
     return smack_from_secid(skb->secmark);
 }
 #else
 static inline struct smack_known *smack_from_skb(struct sk_buff *skb)
 {
     return NULL;
 }
 #endif
 
 /**
  * smack_from_netlbl - Smack data from the IP options in an skb
  * @sk: socket data came in on
  * @family: address family
  * @skb: packet
  *
  * Find the Smack label in the IP options. If it hasn't been
  * added to the netlabel cache, add it here.
  *
  * Returns smack_known of the IP options or NULL if that won't work.
  */
 static struct smack_known *smack_from_netlbl(const struct sock *sk, u16 family,
                          struct sk_buff *skb)
 {
     struct netlbl_lsm_secattr secattr;
     struct socket_smack *ssp = NULL;
     struct smack_known *skp = NULL;
 
     netlbl_secattr_init(&secattr);
 
     if (sk)
         ssp = sk->sk_security;
 
     if (netlbl_skbuff_getattr(skb, family, &secattr) == 0) {
         skp = smack_from_secattr(&secattr, ssp);
         if (secattr.flags & NETLBL_SECATTR_CACHEABLE)
             netlbl_cache_add(skb, family, &skp->smk_netlabel);
     }
 
     netlbl_secattr_destroy(&secattr);
 
     return skp;
 }
 
 /**
  * smack_socket_sock_rcv_skb - Smack packet delivery access check
  * @sk: socket
  * @skb: packet
  *
  * Returns 0 if the packet should be delivered, an error code otherwise
  */
 static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 {
     struct socket_smack *ssp = sk->sk_security;
     struct smack_known *skp = NULL;
     int rc = 0;
     struct smk_audit_info ad;
     u16 family = sk->sk_family;
 #ifdef CONFIG_AUDIT
     struct lsm_network_audit net;
 #endif
 #if IS_ENABLED(CONFIG_IPV6)
     struct sockaddr_in6 sadd;
     int proto;
 
     if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
         family = PF_INET;
 #endif /* CONFIG_IPV6 */
 
     switch (family) {
     case PF_INET:
         /*
          * If there is a secmark use it rather than the CIPSO label.
          * If there is no secmark fall back to CIPSO.
          * The secmark is assumed to reflect policy better.
          */
         skp = smack_from_skb(skb);
         if (skp == NULL) {
             skp = smack_from_netlbl(sk, family, skb);
             if (skp == NULL)
                 skp = smack_net_ambient;
         }
 
 #ifdef CONFIG_AUDIT
         smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
         ad.a.u.net->family = family;
         ad.a.u.net->netif = skb->skb_iif;
         ipv4_skb_to_auditdata(skb, &ad.a, NULL);
 #endif
         /*
          * Receiving a packet requires that the other end
          * be able to write here. Read access is not required.
          * This is the simplist possible security model
          * for networking.
          */
         rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
         rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in,
                     MAY_WRITE, rc);
         if (rc != 0)
             netlbl_skbuff_err(skb, family, rc, 0);
         break;
 #if IS_ENABLED(CONFIG_IPV6)
     case PF_INET6:
         proto = smk_skb_to_addr_ipv6(skb, &sadd);
         if (proto != IPPROTO_UDP && proto != IPPROTO_UDPLITE &&
             proto != IPPROTO_TCP && proto != IPPROTO_DCCP)
             break;
 #ifdef SMACK_IPV6_SECMARK_LABELING
         skp = smack_from_skb(skb);
         if (skp == NULL) {
             if (smk_ipv6_localhost(&sadd))
                 break;
             skp = smack_ipv6host_label(&sadd);
             if (skp == NULL)
                 skp = smack_net_ambient;
         }
 #ifdef CONFIG_AUDIT
         smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
         ad.a.u.net->family = family;
         ad.a.u.net->netif = skb->skb_iif;
         ipv6_skb_to_auditdata(skb, &ad.a, NULL);
 #endif /* CONFIG_AUDIT */
         rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
         rc = smk_bu_note("IPv6 delivery", skp, ssp->smk_in,
                     MAY_WRITE, rc);
 #endif /* SMACK_IPV6_SECMARK_LABELING */
 #ifdef SMACK_IPV6_PORT_LABELING
         rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING);
 #endif /* SMACK_IPV6_PORT_LABELING */
         if (rc != 0)
             icmpv6_send(skb, ICMPV6_DEST_UNREACH,
                     ICMPV6_ADM_PROHIBITED, 0);
         break;
 #endif /* CONFIG_IPV6 */
     }
 
     return rc;
 }
 
 /**
  * smack_socket_getpeersec_stream - pull in packet label
  * @sock: the socket
  * @optval: user's destination
  * @optlen: size thereof
  * @len: max thereof
  *
  * returns zero on success, an error code otherwise
  */
 static int smack_socket_getpeersec_stream(struct socket *sock,
                       char __user *optval,
                       int __user *optlen, unsigned len)
 {
     struct socket_smack *ssp;
     char *rcp = "";
     int slen = 1;
     int rc = 0;
 
     ssp = sock->sk->sk_security;
     if (ssp->smk_packet != NULL) {
         rcp = ssp->smk_packet->smk_known;
         slen = strlen(rcp) + 1;
     }
 
     if (slen > len)
         rc = -ERANGE;
     else if (copy_to_user(optval, rcp, slen) != 0)
         rc = -EFAULT;
 
     if (put_user(slen, optlen) != 0)
         rc = -EFAULT;
 
     return rc;
 }
 
 
 /**
  * smack_socket_getpeersec_dgram - pull in packet label
  * @sock: the peer socket
  * @skb: packet data
  * @secid: pointer to where to put the secid of the packet
  *
  * Sets the netlabel socket state on sk from parent
  */
 static int smack_socket_getpeersec_dgram(struct socket *sock,
                      struct sk_buff *skb, u32 *secid)
 
 {
     struct socket_smack *ssp = NULL;
     struct smack_known *skp;
     struct sock *sk = NULL;
     int family = PF_UNSPEC;
     u32 s = 0;  /* 0 is the invalid secid */
 
     if (skb != NULL) {
         if (skb->protocol == htons(ETH_P_IP))
             family = PF_INET;
 #if IS_ENABLED(CONFIG_IPV6)
         else if (skb->protocol == htons(ETH_P_IPV6))
             family = PF_INET6;
 #endif /* CONFIG_IPV6 */
     }
     if (family == PF_UNSPEC && sock != NULL)
         family = sock->sk->sk_family;
 
     switch (family) {
     case PF_UNIX:
         ssp = sock->sk->sk_security;
         s = ssp->smk_out->smk_secid;
         break;
     case PF_INET:
         skp = smack_from_skb(skb);
         if (skp) {
             s = skp->smk_secid;
             break;
         }
         /*
          * Translate what netlabel gave us.
          */
         if (sock != NULL)
             sk = sock->sk;
         skp = smack_from_netlbl(sk, family, skb);
         if (skp != NULL)
             s = skp->smk_secid;
         break;
     case PF_INET6:
 #ifdef SMACK_IPV6_SECMARK_LABELING
         skp = smack_from_skb(skb);
         if (skp)
             s = skp->smk_secid;
 #endif
         break;
     }
     *secid = s;
     if (s == 0)
         return -EINVAL;
     return 0;
 }
 
 /**
  * smack_sock_graft - Initialize a newly created socket with an existing sock
  * @sk: child sock
  * @parent: parent socket
  *
  * Set the smk_{in,out} state of an existing sock based on the process that
  * is creating the new socket.
  */
 static void smack_sock_graft(struct sock *sk, struct socket *parent)
 {
     struct socket_smack *ssp;
     struct smack_known *skp = smk_of_current();
 
     if (sk == NULL ||
         (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
         return;
 
     ssp = sk->sk_security;
     ssp->smk_in = skp;
     ssp->smk_out = skp;
     /* cssp->smk_packet is already set in smack_inet_csk_clone() */
 }
 
 /**
  * smack_inet_conn_request - Smack access check on connect
  * @sk: socket involved
  * @skb: packet
  * @req: unused
  *
  * Returns 0 if a task with the packet label could write to
  * the socket, otherwise an error code
  */
 static int smack_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
                    struct request_sock *req)
 {
     u16 family = sk->sk_family;
     struct smack_known *skp;
     struct socket_smack *ssp = sk->sk_security;
     struct sockaddr_in addr;
     struct iphdr *hdr;
     struct smack_known *hskp;
     int rc;
     struct smk_audit_info ad;
 #ifdef CONFIG_AUDIT
     struct lsm_network_audit net;
 #endif
 
 #if IS_ENABLED(CONFIG_IPV6)
     if (family == PF_INET6) {
         /*
          * Handle mapped IPv4 packets arriving
          * via IPv6 sockets. Don't set up netlabel
          * processing on IPv6.
          */
         if (skb->protocol == htons(ETH_P_IP))
             family = PF_INET;
         else
             return 0;
     }
 #endif /* CONFIG_IPV6 */
 
     /*
      * If there is a secmark use it rather than the CIPSO label.
      * If there is no secmark fall back to CIPSO.
      * The secmark is assumed to reflect policy better.
      */
     skp = smack_from_skb(skb);
     if (skp == NULL) {
         skp = smack_from_netlbl(sk, family, skb);
         if (skp == NULL)
             skp = &smack_known_huh;
     }
 
 #ifdef CONFIG_AUDIT
     smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
     ad.a.u.net->family = family;
     ad.a.u.net->netif = skb->skb_iif;
     ipv4_skb_to_auditdata(skb, &ad.a, NULL);
 #endif
     /*
      * Receiving a packet requires that the other end be able to write
      * here. Read access is not required.
      */
     rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
     rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in, MAY_WRITE, rc);
     if (rc != 0)
         return rc;
 
     /*
      * Save the peer's label in the request_sock so we can later setup
      * smk_packet in the child socket so that SO_PEERCRED can report it.
      */
     req->peer_secid = skp->smk_secid;
 
     /*
      * We need to decide if we want to label the incoming connection here
      * if we do we only need to label the request_sock and the stack will
      * propagate the wire-label to the sock when it is created.
      */
     hdr = ip_hdr(skb);
     addr.sin_addr.s_addr = hdr->saddr;
     rcu_read_lock();
     hskp = smack_ipv4host_label(&addr);
     rcu_read_unlock();
 
     if (hskp == NULL)
         rc = netlbl_req_setattr(req, &skp->smk_netlabel);
     else
         netlbl_req_delattr(req);
 
     return rc;
 }
 
 /**
  * smack_inet_csk_clone - Copy the connection information to the new socket
  * @sk: the new socket
  * @req: the connection's request_sock
  *
  * Transfer the connection's peer label to the newly created socket.
  */
 static void smack_inet_csk_clone(struct sock *sk,
                  const struct request_sock *req)
 {
     struct socket_smack *ssp = sk->sk_security;
     struct smack_known *skp;
 
     if (req->peer_secid != 0) {
         skp = smack_from_secid(req->peer_secid);
         ssp->smk_packet = skp;
     } else
         ssp->smk_packet = NULL;
 }
 
 /*
  * Key management security hooks
  *
  * Casey has not tested key support very heavily.
  * The permission check is most likely too restrictive.
  * If you care about keys please have a look.
  */
 #ifdef CONFIG_KEYS
 
 /**
  * smack_key_alloc - Set the key security blob
  * @key: object
  * @cred: the credentials to use
  * @flags: unused
  *
  * No allocation required
  *
  * Returns 0
  */
 static int smack_key_alloc(struct key *key, const struct cred *cred,
                unsigned long flags)
 {
     struct smack_known *skp = smk_of_task(smack_cred(cred));
 
     key->security = skp;
     return 0;
 }
 
 /**
  * smack_key_free - Clear the key security blob
  * @key: the object
  *
  * Clear the blob pointer
  */
 static void smack_key_free(struct key *key)
 {
     key->security = NULL;
 }
 
 /**
  * smack_key_permission - Smack access on a key
  * @key_ref: gets to the object
  * @cred: the credentials to use
  * @need_perm: requested key permission
  *
  * Return 0 if the task has read and write to the object,
  * an error code otherwise
  */
 static int smack_key_permission(key_ref_t key_ref,
                 const struct cred *cred,
                 enum key_need_perm need_perm)
 {
     struct key *keyp;
     struct smk_audit_info ad;
     struct smack_known *tkp = smk_of_task(smack_cred(cred));
     int request = 0;
     int rc;
 
     /*
      * Validate requested permissions
      */
     switch (need_perm) {
     case KEY_NEED_READ:
     case KEY_NEED_SEARCH:
     case KEY_NEED_VIEW:
         request |= MAY_READ;
         break;
     case KEY_NEED_WRITE:
     case KEY_NEED_LINK:
     case KEY_NEED_SETATTR:
         request |= MAY_WRITE;
         break;
     case KEY_NEED_UNSPECIFIED:
     case KEY_NEED_UNLINK:
     case KEY_SYSADMIN_OVERRIDE:
     case KEY_AUTHTOKEN_OVERRIDE:
     case KEY_DEFER_PERM_CHECK:
         return 0;
     default:
         return -EINVAL;
     }
 
     keyp = key_ref_to_ptr(key_ref);
     if (keyp == NULL)
         return -EINVAL;
     /*
      * If the key hasn't been initialized give it access so that
      * it may do so.
      */
     if (keyp->security == NULL)
         return 0;
     /*
      * This should not occur
      */
     if (tkp == NULL)
         return -EACCES;
 
     if (smack_privileged(CAP_MAC_OVERRIDE))
         return 0;
 
 #ifdef CONFIG_AUDIT
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
     ad.a.u.key_struct.key = keyp->serial;
     ad.a.u.key_struct.key_desc = keyp->description;
 #endif
     rc = smk_access(tkp, keyp->security, request, &ad);
     rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
     return rc;
 }
 
 /*
  * smack_key_getsecurity - Smack label tagging the key
  * @key points to the key to be queried
  * @_buffer points to a pointer that should be set to point to the
  * resulting string (if no label or an error occurs).
  * Return the length of the string (including terminating NUL) or -ve if
  * an error.
  * May also return 0 (and a NULL buffer pointer) if there is no label.
  */
 static int smack_key_getsecurity(struct key *key, char **_buffer)
 {
     struct smack_known *skp = key->security;
     size_t length;
     char *copy;
 
     if (key->security == NULL) {
         *_buffer = NULL;
         return 0;
     }
 
     copy = kstrdup(skp->smk_known, GFP_KERNEL);
     if (copy == NULL)
         return -ENOMEM;
     length = strlen(copy) + 1;
 
     *_buffer = copy;
     return length;
 }
 
 
 #ifdef CONFIG_KEY_NOTIFICATIONS
 /**
  * smack_watch_key - Smack access to watch a key for notifications.
  * @key: The key to be watched
  *
  * Return 0 if the @watch->cred has permission to read from the key object and
  * an error otherwise.
  */
 static int smack_watch_key(struct key *key)
 {
     struct smk_audit_info ad;
     struct smack_known *tkp = smk_of_current();
     int rc;
 
     if (key == NULL)
         return -EINVAL;
     /*
      * If the key hasn't been initialized give it access so that
      * it may do so.
      */
     if (key->security == NULL)
         return 0;
     /*
      * This should not occur
      */
     if (tkp == NULL)
         return -EACCES;
 
     if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
         return 0;
 
 #ifdef CONFIG_AUDIT
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
     ad.a.u.key_struct.key = key->serial;
     ad.a.u.key_struct.key_desc = key->description;
 #endif
     rc = smk_access(tkp, key->security, MAY_READ, &ad);
     rc = smk_bu_note("key watch", tkp, key->security, MAY_READ, rc);
     return rc;
 }
 #endif /* CONFIG_KEY_NOTIFICATIONS */
 #endif /* CONFIG_KEYS */
 
 #ifdef CONFIG_WATCH_QUEUE
 /**
  * smack_post_notification - Smack access to post a notification to a queue
  * @w_cred: The credentials of the watcher.
  * @cred: The credentials of the event source (may be NULL).
  * @n: The notification message to be posted.
  */
 static int smack_post_notification(const struct cred *w_cred,
                    const struct cred *cred,
                    struct watch_notification *n)
 {
     struct smk_audit_info ad;
     struct smack_known *subj, *obj;
     int rc;
 
     /* Always let maintenance notifications through. */
     if (n->type == WATCH_TYPE_META)
         return 0;
 
     if (!cred)
         return 0;
     subj = smk_of_task(smack_cred(cred));
     obj = smk_of_task(smack_cred(w_cred));
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NOTIFICATION);
     rc = smk_access(subj, obj, MAY_WRITE, &ad);
     rc = smk_bu_note("notification", subj, obj, MAY_WRITE, rc);
     return rc;
 }
 #endif /* CONFIG_WATCH_QUEUE */
 
 /*
  * Smack Audit hooks
  *
  * Audit requires a unique representation of each Smack specific
  * rule. This unique representation is used to distinguish the
  * object to be audited from remaining kernel objects and also
  * works as a glue between the audit hooks.
  *
  * Since repository entries are added but never deleted, we'll use
  * the smack_known label address related to the given audit rule as
  * the needed unique representation. This also better fits the smack
  * model where nearly everything is a label.
  */
 #ifdef CONFIG_AUDIT
 
 /**
  * smack_audit_rule_init - Initialize a smack audit rule
  * @field: audit rule fields given from user-space (audit.h)
  * @op: required testing operator (=, !=, >, <, ...)
  * @rulestr: smack label to be audited
  * @vrule: pointer to save our own audit rule representation
  *
  * Prepare to audit cases where (@field @op @rulestr) is true.
  * The label to be audited is created if necessay.
  */
 static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
 {
     struct smack_known *skp;
     char **rule = (char **)vrule;
     *rule = NULL;
 
     if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
         return -EINVAL;
 
     if (op != Audit_equal && op != Audit_not_equal)
         return -EINVAL;
 
     skp = smk_import_entry(rulestr, 0);
     if (IS_ERR(skp))
         return PTR_ERR(skp);
 
     *rule = skp->smk_known;
 
     return 0;
 }
 
 /**
  * smack_audit_rule_known - Distinguish Smack audit rules
  * @krule: rule of interest, in Audit kernel representation format
  *
  * This is used to filter Smack rules from remaining Audit ones.
  * If it's proved that this rule belongs to us, the
  * audit_rule_match hook will be called to do the final judgement.
  */
 static int smack_audit_rule_known(struct audit_krule *krule)
 {
     struct audit_field *f;
     int i;
 
     for (i = 0; i < krule->field_count; i++) {
         f = &krule->fields[i];
 
         if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
             return 1;
     }
 
     return 0;
 }
 
 /**
  * smack_audit_rule_match - Audit given object ?
  * @secid: security id for identifying the object to test
  * @field: audit rule flags given from user-space
  * @op: required testing operator
  * @vrule: smack internal rule presentation
  *
  * The core Audit hook. It's used to take the decision of
  * whether to audit or not to audit a given object.
  */
 static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule)
 {
     struct smack_known *skp;
     char *rule = vrule;
 
     if (unlikely(!rule)) {
         WARN_ONCE(1, "Smack: missing rule\n");
         return -ENOENT;
     }
 
     if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
         return 0;
 
     skp = smack_from_secid(secid);
 
     /*
      * No need to do string comparisons. If a match occurs,
      * both pointers will point to the same smack_known
      * label.
      */
     if (op == Audit_equal)
         return (rule == skp->smk_known);
     if (op == Audit_not_equal)
         return (rule != skp->smk_known);
 
     return 0;
 }
 
 /*
  * There is no need for a smack_audit_rule_free hook.
  * No memory was allocated.
  */
 
 #endif /* CONFIG_AUDIT */
 
 /**
  * smack_ismaclabel - check if xattr @name references a smack MAC label
  * @name: Full xattr name to check.
  */
 static int smack_ismaclabel(const char *name)
 {
     return (strcmp(name, XATTR_SMACK_SUFFIX) == 0);
 }
 
 
 /**
  * smack_secid_to_secctx - return the smack label for a secid
  * @secid: incoming integer
  * @secdata: destination
  * @seclen: how long it is
  *
  * Exists for networking code.
  */
 static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
 {
     struct smack_known *skp = smack_from_secid(secid);
 
     if (secdata)
         *secdata = skp->smk_known;
     *seclen = strlen(skp->smk_known);
     return 0;
 }
 
 /**
  * smack_secctx_to_secid - return the secid for a smack label
  * @secdata: smack label
  * @seclen: how long result is
  * @secid: outgoing integer
  *
  * Exists for audit and networking code.
  */
 static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
 {
     struct smack_known *skp = smk_find_entry(secdata);
 
     if (skp)
         *secid = skp->smk_secid;
     else
         *secid = 0;
     return 0;
 }
 
 /*
  * There used to be a smack_release_secctx hook
  * that did nothing back when hooks were in a vector.
  * Now that there's a list such a hook adds cost.
  */
 
 static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
 {
     return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx,
                        ctxlen, 0);
 }
 
 static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
 {
     return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SMACK,
                      ctx, ctxlen, 0);
 }
 
 static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
 {
     struct smack_known *skp = smk_of_inode(inode);
 
     *ctx = skp->smk_known;
     *ctxlen = strlen(skp->smk_known);
     return 0;
 }
 
 static int smack_inode_copy_up(struct dentry *dentry, struct cred **new)
 {
 
     struct task_smack *tsp;
     struct smack_known *skp;
     struct inode_smack *isp;
     struct cred *new_creds = *new;
 
     if (new_creds == NULL) {
         new_creds = prepare_creds();
         if (new_creds == NULL)
             return -ENOMEM;
     }
 
     tsp = smack_cred(new_creds);
 
     /*
      * Get label from overlay inode and set it in create_sid
      */
     isp = smack_inode(d_inode(dentry));
     skp = isp->smk_inode;
     tsp->smk_task = skp;
     *new = new_creds;
     return 0;
 }
 
 static int smack_inode_copy_up_xattr(const char *name)
 {
     /*
      * Return 1 if this is the smack access Smack attribute.
      */
     if (strcmp(name, XATTR_NAME_SMACK) == 0)
         return 1;
 
     return -EOPNOTSUPP;
 }
 
 static int smack_dentry_create_files_as(struct dentry *dentry, int mode,
                     struct qstr *name,
                     const struct cred *old,
                     struct cred *new)
 {
     struct task_smack *otsp = smack_cred(old);
     struct task_smack *ntsp = smack_cred(new);
     struct inode_smack *isp;
     int may;
 
     /*
      * Use the process credential unless all of
      * the transmuting criteria are met
      */
     ntsp->smk_task = otsp->smk_task;
 
     /*
      * the attribute of the containing directory
      */
     isp = smack_inode(d_inode(dentry->d_parent));
 
     if (isp->smk_flags & SMK_INODE_TRANSMUTE) {
         rcu_read_lock();
         may = smk_access_entry(otsp->smk_task->smk_known,
                        isp->smk_inode->smk_known,
                        &otsp->smk_task->smk_rules);
         rcu_read_unlock();
 
         /*
          * If the directory is transmuting and the rule
          * providing access is transmuting use the containing
          * directory label instead of the process label.
          */
         if (may > 0 && (may & MAY_TRANSMUTE))
             ntsp->smk_task = isp->smk_inode;
     }
     return 0;
 }
 
 #ifdef CONFIG_IO_URING
 /**
  * smack_uring_override_creds - Is io_uring cred override allowed?
  * @new: the target creds
  *
  * Check to see if the current task is allowed to override it's credentials
  * to service an io_uring operation.
  */
 static int smack_uring_override_creds(const struct cred *new)
 {
     struct task_smack *tsp = smack_cred(current_cred());
     struct task_smack *nsp = smack_cred(new);
 
     /*
      * Allow the degenerate case where the new Smack value is
      * the same as the current Smack value.
      */
     if (tsp->smk_task == nsp->smk_task)
         return 0;
 
     if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
         return 0;
 
     return -EPERM;
 }
 
 /**
  * smack_uring_sqpoll - check if a io_uring polling thread can be created
  *
  * Check to see if the current task is allowed to create a new io_uring
  * kernel polling thread.
  */
 static int smack_uring_sqpoll(void)
 {
     if (smack_privileged_cred(CAP_MAC_ADMIN, current_cred()))
         return 0;
 
     return -EPERM;
 }
 
 /**
  * smack_uring_cmd - check on file operations for io_uring
  * @ioucmd: the command in question
  *
  * Make a best guess about whether a io_uring "command" should
  * be allowed. Use the same logic used for determining if the
  * file could be opened for read in the absence of better criteria.
  */
 static int smack_uring_cmd(struct io_uring_cmd *ioucmd)
 {
     struct file *file = ioucmd->file;
     struct smk_audit_info ad;
     struct task_smack *tsp;
     struct inode *inode;
     int rc;
 
     if (!file)
         return -EINVAL;
 
     tsp = smack_cred(file->f_cred);
     inode = file_inode(file);
 
     smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
     smk_ad_setfield_u_fs_path(&ad, file->f_path);
     rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
     rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc);
 
     return rc;
 }
 
 #endif /* CONFIG_IO_URING */
 
 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 *),
     .lbs_superblock = sizeof(struct superblock_smack),
 };
 
 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),
     LSM_HOOK_INIT(syslog, smack_syslog),
 
     LSM_HOOK_INIT(fs_context_dup, smack_fs_context_dup),
     LSM_HOOK_INIT(fs_context_parse_param, smack_fs_context_parse_param),
 
     LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
     LSM_HOOK_INIT(sb_free_mnt_opts, smack_free_mnt_opts),
     LSM_HOOK_INIT(sb_eat_lsm_opts, smack_sb_eat_lsm_opts),
     LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
     LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts),
 
     LSM_HOOK_INIT(bprm_creds_for_exec, smack_bprm_creds_for_exec),
 
     LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_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),
     LSM_HOOK_INIT(inode_rmdir, smack_inode_rmdir),
     LSM_HOOK_INIT(inode_rename, smack_inode_rename),
     LSM_HOOK_INIT(inode_permission, smack_inode_permission),
     LSM_HOOK_INIT(inode_setattr, smack_inode_setattr),
     LSM_HOOK_INIT(inode_getattr, smack_inode_getattr),
     LSM_HOOK_INIT(inode_setxattr, smack_inode_setxattr),
     LSM_HOOK_INIT(inode_post_setxattr, smack_inode_post_setxattr),
     LSM_HOOK_INIT(inode_getxattr, smack_inode_getxattr),
     LSM_HOOK_INIT(inode_removexattr, smack_inode_removexattr),
     LSM_HOOK_INIT(inode_getsecurity, smack_inode_getsecurity),
     LSM_HOOK_INIT(inode_setsecurity, smack_inode_setsecurity),
     LSM_HOOK_INIT(inode_listsecurity, smack_inode_listsecurity),
     LSM_HOOK_INIT(inode_getsecid, smack_inode_getsecid),
 
     LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_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),
     LSM_HOOK_INIT(mmap_file, smack_mmap_file),
     LSM_HOOK_INIT(mmap_addr, cap_mmap_addr),
     LSM_HOOK_INIT(file_set_fowner, smack_file_set_fowner),
     LSM_HOOK_INIT(file_send_sigiotask, smack_file_send_sigiotask),
     LSM_HOOK_INIT(file_receive, smack_file_receive),
 
     LSM_HOOK_INIT(file_open, smack_file_open),
 
     LSM_HOOK_INIT(cred_alloc_blank, smack_cred_alloc_blank),
     LSM_HOOK_INIT(cred_free, smack_cred_free),
     LSM_HOOK_INIT(cred_prepare, smack_cred_prepare),
     LSM_HOOK_INIT(cred_transfer, smack_cred_transfer),
     LSM_HOOK_INIT(cred_getsecid, smack_cred_getsecid),
     LSM_HOOK_INIT(kernel_act_as, smack_kernel_act_as),
     LSM_HOOK_INIT(kernel_create_files_as, smack_kernel_create_files_as),
     LSM_HOOK_INIT(task_setpgid, smack_task_setpgid),
     LSM_HOOK_INIT(task_getpgid, smack_task_getpgid),
     LSM_HOOK_INIT(task_getsid, smack_task_getsid),
     LSM_HOOK_INIT(current_getsecid_subj, smack_current_getsecid_subj),
     LSM_HOOK_INIT(task_getsecid_obj, smack_task_getsecid_obj),
     LSM_HOOK_INIT(task_setnice, smack_task_setnice),
     LSM_HOOK_INIT(task_setioprio, smack_task_setioprio),
     LSM_HOOK_INIT(task_getioprio, smack_task_getioprio),
     LSM_HOOK_INIT(task_setscheduler, smack_task_setscheduler),
     LSM_HOOK_INIT(task_getscheduler, smack_task_getscheduler),
     LSM_HOOK_INIT(task_movememory, smack_task_movememory),
     LSM_HOOK_INIT(task_kill, smack_task_kill),
     LSM_HOOK_INIT(task_to_inode, smack_task_to_inode),
 
     LSM_HOOK_INIT(ipc_permission, smack_ipc_permission),
     LSM_HOOK_INIT(ipc_getsecid, smack_ipc_getsecid),
 
     LSM_HOOK_INIT(msg_msg_alloc_security, smack_msg_msg_alloc_security),
 
     LSM_HOOK_INIT(msg_queue_alloc_security, smack_ipc_alloc_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_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_associate, smack_sem_associate),
     LSM_HOOK_INIT(sem_semctl, smack_sem_semctl),
     LSM_HOOK_INIT(sem_semop, smack_sem_semop),
 
     LSM_HOOK_INIT(d_instantiate, smack_d_instantiate),
 
     LSM_HOOK_INIT(getprocattr, smack_getprocattr),
     LSM_HOOK_INIT(setprocattr, smack_setprocattr),
 
     LSM_HOOK_INIT(unix_stream_connect, smack_unix_stream_connect),
     LSM_HOOK_INIT(unix_may_send, smack_unix_may_send),
 
     LSM_HOOK_INIT(socket_post_create, smack_socket_post_create),
     LSM_HOOK_INIT(socket_socketpair, smack_socket_socketpair),
 #ifdef SMACK_IPV6_PORT_LABELING
     LSM_HOOK_INIT(socket_bind, smack_socket_bind),
 #endif
     LSM_HOOK_INIT(socket_connect, smack_socket_connect),
     LSM_HOOK_INIT(socket_sendmsg, smack_socket_sendmsg),
     LSM_HOOK_INIT(socket_sock_rcv_skb, smack_socket_sock_rcv_skb),
     LSM_HOOK_INIT(socket_getpeersec_stream, smack_socket_getpeersec_stream),
     LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram),
     LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security),
     LSM_HOOK_INIT(sk_free_security, smack_sk_free_security),
     LSM_HOOK_INIT(sock_graft, smack_sock_graft),
     LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request),
     LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone),
 
  /* key management security hooks */
 #ifdef CONFIG_KEYS
     LSM_HOOK_INIT(key_alloc, smack_key_alloc),
     LSM_HOOK_INIT(key_free, smack_key_free),
     LSM_HOOK_INIT(key_permission, smack_key_permission),
     LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
 #ifdef CONFIG_KEY_NOTIFICATIONS
     LSM_HOOK_INIT(watch_key, smack_watch_key),
 #endif
 #endif /* CONFIG_KEYS */
 
 #ifdef CONFIG_WATCH_QUEUE
     LSM_HOOK_INIT(post_notification, smack_post_notification),
 #endif
 
  /* Audit hooks */
 #ifdef CONFIG_AUDIT
     LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init),
     LSM_HOOK_INIT(audit_rule_known, smack_audit_rule_known),
     LSM_HOOK_INIT(audit_rule_match, smack_audit_rule_match),
 #endif /* CONFIG_AUDIT */
 
     LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
     LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
     LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
     LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
     LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
     LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
     LSM_HOOK_INIT(inode_copy_up, smack_inode_copy_up),
     LSM_HOOK_INIT(inode_copy_up_xattr, smack_inode_copy_up_xattr),
     LSM_HOOK_INIT(dentry_create_files_as, smack_dentry_create_files_as),
 #ifdef CONFIG_IO_URING
     LSM_HOOK_INIT(uring_override_creds, smack_uring_override_creds),
     LSM_HOOK_INIT(uring_sqpoll, smack_uring_sqpoll),
     LSM_HOOK_INIT(uring_cmd, smack_uring_cmd),
 #endif
 };
 
 
 static __init void init_smack_known_list(void)
 {
     /*
      * Initialize rule list locks
      */
     mutex_init(&smack_known_huh.smk_rules_lock);
     mutex_init(&smack_known_hat.smk_rules_lock);
     mutex_init(&smack_known_floor.smk_rules_lock);
     mutex_init(&smack_known_star.smk_rules_lock);
     mutex_init(&smack_known_web.smk_rules_lock);
     /*
      * Initialize rule lists
      */
     INIT_LIST_HEAD(&smack_known_huh.smk_rules);
     INIT_LIST_HEAD(&smack_known_hat.smk_rules);
     INIT_LIST_HEAD(&smack_known_star.smk_rules);
     INIT_LIST_HEAD(&smack_known_floor.smk_rules);
     INIT_LIST_HEAD(&smack_known_web.smk_rules);
     /*
      * Create the known labels list
      */
     smk_insert_entry(&smack_known_huh);
     smk_insert_entry(&smack_known_hat);
     smk_insert_entry(&smack_known_star);
     smk_insert_entry(&smack_known_floor);
     smk_insert_entry(&smack_known_web);
 }
 
 /**
  * smack_init - initialize the smack system
  *
  * Returns 0 on success, -ENOMEM is there's no memory
  */
 static __init int smack_init(void)
 {
     struct cred *cred = (struct cred *) current->cred;
     struct task_smack *tsp;
 
     smack_rule_cache = KMEM_CACHE(smack_rule, 0);
     if (!smack_rule_cache)
         return -ENOMEM;
 
     /*
      * 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");
 #ifdef CONFIG_SECURITY_SMACK_NETFILTER
     pr_info("Smack:  Netfilter enabled.\n");
 #endif
 #ifdef SMACK_IPV6_PORT_LABELING
     pr_info("Smack:  IPv6 port labeling enabled.\n");
 #endif
 #ifdef SMACK_IPV6_SECMARK_LABELING
     pr_info("Smack:  IPv6 Netfilter enabled.\n");
 #endif
 
     /* initialize the smack_known_list */
     init_smack_known_list();
 
     return 0;
 }
 
 /*
  * Smack requires early initialization in order to label
  * all processes and objects when they are created.
  */
 DEFINE_LSM(smack) = {
     .name = "smack",
     .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
     .blobs = &smack_blob_sizes,
     .init = smack_init,
 };