linux/security/selinux/selinuxfs.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/* Updated: Karl MacMillan <kmacmillan@tresys.com>
   3 *
   4 *      Added conditional policy language extensions
   5 *
   6 *  Updated: Hewlett-Packard <paul@paul-moore.com>
   7 *
   8 *      Added support for the policy capability bitmap
   9 *
  10 * Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
  11 * Copyright (C) 2003 - 2004 Tresys Technology, LLC
  12 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13 */
  14
  15#include <linux/kernel.h>
  16#include <linux/pagemap.h>
  17#include <linux/slab.h>
  18#include <linux/vmalloc.h>
  19#include <linux/fs.h>
  20#include <linux/fs_context.h>
  21#include <linux/mount.h>
  22#include <linux/mutex.h>
  23#include <linux/init.h>
  24#include <linux/string.h>
  25#include <linux/security.h>
  26#include <linux/major.h>
  27#include <linux/seq_file.h>
  28#include <linux/percpu.h>
  29#include <linux/audit.h>
  30#include <linux/uaccess.h>
  31#include <linux/kobject.h>
  32#include <linux/ctype.h>
  33
  34/* selinuxfs pseudo filesystem for exporting the security policy API.
  35   Based on the proc code and the fs/nfsd/nfsctl.c code. */
  36
  37#include "flask.h"
  38#include "avc.h"
  39#include "avc_ss.h"
  40#include "security.h"
  41#include "objsec.h"
  42#include "conditional.h"
  43
  44enum sel_inos {
  45        SEL_ROOT_INO = 2,
  46        SEL_LOAD,       /* load policy */
  47        SEL_ENFORCE,    /* get or set enforcing status */
  48        SEL_CONTEXT,    /* validate context */
  49        SEL_ACCESS,     /* compute access decision */
  50        SEL_CREATE,     /* compute create labeling decision */
  51        SEL_RELABEL,    /* compute relabeling decision */
  52        SEL_USER,       /* compute reachable user contexts */
  53        SEL_POLICYVERS, /* return policy version for this kernel */
  54        SEL_COMMIT_BOOLS, /* commit new boolean values */
  55        SEL_MLS,        /* return if MLS policy is enabled */
  56        SEL_DISABLE,    /* disable SELinux until next reboot */
  57        SEL_MEMBER,     /* compute polyinstantiation membership decision */
  58        SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
  59        SEL_COMPAT_NET, /* whether to use old compat network packet controls */
  60        SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
  61        SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
  62        SEL_STATUS,     /* export current status using mmap() */
  63        SEL_POLICY,     /* allow userspace to read the in kernel policy */
  64        SEL_VALIDATE_TRANS, /* compute validatetrans decision */
  65        SEL_INO_NEXT,   /* The next inode number to use */
  66};
  67
  68struct selinux_fs_info {
  69        struct dentry *bool_dir;
  70        unsigned int bool_num;
  71        char **bool_pending_names;
  72        unsigned int *bool_pending_values;
  73        struct dentry *class_dir;
  74        unsigned long last_class_ino;
  75        bool policy_opened;
  76        struct dentry *policycap_dir;
  77        struct mutex mutex;
  78        unsigned long last_ino;
  79        struct selinux_state *state;
  80        struct super_block *sb;
  81};
  82
  83static int selinux_fs_info_create(struct super_block *sb)
  84{
  85        struct selinux_fs_info *fsi;
  86
  87        fsi = kzalloc(sizeof(*fsi), GFP_KERNEL);
  88        if (!fsi)
  89                return -ENOMEM;
  90
  91        mutex_init(&fsi->mutex);
  92        fsi->last_ino = SEL_INO_NEXT - 1;
  93        fsi->state = &selinux_state;
  94        fsi->sb = sb;
  95        sb->s_fs_info = fsi;
  96        return 0;
  97}
  98
  99static void selinux_fs_info_free(struct super_block *sb)
 100{
 101        struct selinux_fs_info *fsi = sb->s_fs_info;
 102        int i;
 103
 104        if (fsi) {
 105                for (i = 0; i < fsi->bool_num; i++)
 106                        kfree(fsi->bool_pending_names[i]);
 107                kfree(fsi->bool_pending_names);
 108                kfree(fsi->bool_pending_values);
 109        }
 110        kfree(sb->s_fs_info);
 111        sb->s_fs_info = NULL;
 112}
 113
 114#define SEL_INITCON_INO_OFFSET          0x01000000
 115#define SEL_BOOL_INO_OFFSET             0x02000000
 116#define SEL_CLASS_INO_OFFSET            0x04000000
 117#define SEL_POLICYCAP_INO_OFFSET        0x08000000
 118#define SEL_INO_MASK                    0x00ffffff
 119
 120#define TMPBUFLEN       12
 121static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
 122                                size_t count, loff_t *ppos)
 123{
 124        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 125        char tmpbuf[TMPBUFLEN];
 126        ssize_t length;
 127
 128        length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 129                           enforcing_enabled(fsi->state));
 130        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 131}
 132
 133#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 134static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
 135                                 size_t count, loff_t *ppos)
 136
 137{
 138        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 139        struct selinux_state *state = fsi->state;
 140        char *page = NULL;
 141        ssize_t length;
 142        int old_value, new_value;
 143
 144        if (count >= PAGE_SIZE)
 145                return -ENOMEM;
 146
 147        /* No partial writes. */
 148        if (*ppos != 0)
 149                return -EINVAL;
 150
 151        page = memdup_user_nul(buf, count);
 152        if (IS_ERR(page))
 153                return PTR_ERR(page);
 154
 155        length = -EINVAL;
 156        if (sscanf(page, "%d", &new_value) != 1)
 157                goto out;
 158
 159        new_value = !!new_value;
 160
 161        old_value = enforcing_enabled(state);
 162        if (new_value != old_value) {
 163                length = avc_has_perm(&selinux_state,
 164                                      current_sid(), SECINITSID_SECURITY,
 165                                      SECCLASS_SECURITY, SECURITY__SETENFORCE,
 166                                      NULL);
 167                if (length)
 168                        goto out;
 169                audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
 170                        "enforcing=%d old_enforcing=%d auid=%u ses=%u"
 171                        " enabled=%d old-enabled=%d lsm=selinux res=1",
 172                        new_value, old_value,
 173                        from_kuid(&init_user_ns, audit_get_loginuid(current)),
 174                        audit_get_sessionid(current),
 175                        selinux_enabled, selinux_enabled);
 176                enforcing_set(state, new_value);
 177                if (new_value)
 178                        avc_ss_reset(state->avc, 0);
 179                selnl_notify_setenforce(new_value);
 180                selinux_status_update_setenforce(state, new_value);
 181                if (!new_value)
 182                        call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 183        }
 184        length = count;
 185out:
 186        kfree(page);
 187        return length;
 188}
 189#else
 190#define sel_write_enforce NULL
 191#endif
 192
 193static const struct file_operations sel_enforce_ops = {
 194        .read           = sel_read_enforce,
 195        .write          = sel_write_enforce,
 196        .llseek         = generic_file_llseek,
 197};
 198
 199static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
 200                                        size_t count, loff_t *ppos)
 201{
 202        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 203        struct selinux_state *state = fsi->state;
 204        char tmpbuf[TMPBUFLEN];
 205        ssize_t length;
 206        ino_t ino = file_inode(filp)->i_ino;
 207        int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
 208                security_get_reject_unknown(state) :
 209                !security_get_allow_unknown(state);
 210
 211        length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
 212        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 213}
 214
 215static const struct file_operations sel_handle_unknown_ops = {
 216        .read           = sel_read_handle_unknown,
 217        .llseek         = generic_file_llseek,
 218};
 219
 220static int sel_open_handle_status(struct inode *inode, struct file *filp)
 221{
 222        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 223        struct page    *status = selinux_kernel_status_page(fsi->state);
 224
 225        if (!status)
 226                return -ENOMEM;
 227
 228        filp->private_data = status;
 229
 230        return 0;
 231}
 232
 233static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
 234                                      size_t count, loff_t *ppos)
 235{
 236        struct page    *status = filp->private_data;
 237
 238        BUG_ON(!status);
 239
 240        return simple_read_from_buffer(buf, count, ppos,
 241                                       page_address(status),
 242                                       sizeof(struct selinux_kernel_status));
 243}
 244
 245static int sel_mmap_handle_status(struct file *filp,
 246                                  struct vm_area_struct *vma)
 247{
 248        struct page    *status = filp->private_data;
 249        unsigned long   size = vma->vm_end - vma->vm_start;
 250
 251        BUG_ON(!status);
 252
 253        /* only allows one page from the head */
 254        if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
 255                return -EIO;
 256        /* disallow writable mapping */
 257        if (vma->vm_flags & VM_WRITE)
 258                return -EPERM;
 259        /* disallow mprotect() turns it into writable */
 260        vma->vm_flags &= ~VM_MAYWRITE;
 261
 262        return remap_pfn_range(vma, vma->vm_start,
 263                               page_to_pfn(status),
 264                               size, vma->vm_page_prot);
 265}
 266
 267static const struct file_operations sel_handle_status_ops = {
 268        .open           = sel_open_handle_status,
 269        .read           = sel_read_handle_status,
 270        .mmap           = sel_mmap_handle_status,
 271        .llseek         = generic_file_llseek,
 272};
 273
 274#ifdef CONFIG_SECURITY_SELINUX_DISABLE
 275static ssize_t sel_write_disable(struct file *file, const char __user *buf,
 276                                 size_t count, loff_t *ppos)
 277
 278{
 279        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 280        char *page;
 281        ssize_t length;
 282        int new_value;
 283        int enforcing;
 284
 285        if (count >= PAGE_SIZE)
 286                return -ENOMEM;
 287
 288        /* No partial writes. */
 289        if (*ppos != 0)
 290                return -EINVAL;
 291
 292        page = memdup_user_nul(buf, count);
 293        if (IS_ERR(page))
 294                return PTR_ERR(page);
 295
 296        length = -EINVAL;
 297        if (sscanf(page, "%d", &new_value) != 1)
 298                goto out;
 299
 300        if (new_value) {
 301                enforcing = enforcing_enabled(fsi->state);
 302                length = selinux_disable(fsi->state);
 303                if (length)
 304                        goto out;
 305                audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
 306                        "enforcing=%d old_enforcing=%d auid=%u ses=%u"
 307                        " enabled=%d old-enabled=%d lsm=selinux res=1",
 308                        enforcing, enforcing,
 309                        from_kuid(&init_user_ns, audit_get_loginuid(current)),
 310                        audit_get_sessionid(current), 0, 1);
 311        }
 312
 313        length = count;
 314out:
 315        kfree(page);
 316        return length;
 317}
 318#else
 319#define sel_write_disable NULL
 320#endif
 321
 322static const struct file_operations sel_disable_ops = {
 323        .write          = sel_write_disable,
 324        .llseek         = generic_file_llseek,
 325};
 326
 327static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
 328                                   size_t count, loff_t *ppos)
 329{
 330        char tmpbuf[TMPBUFLEN];
 331        ssize_t length;
 332
 333        length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
 334        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 335}
 336
 337static const struct file_operations sel_policyvers_ops = {
 338        .read           = sel_read_policyvers,
 339        .llseek         = generic_file_llseek,
 340};
 341
 342/* declaration for sel_write_load */
 343static int sel_make_bools(struct selinux_fs_info *fsi);
 344static int sel_make_classes(struct selinux_fs_info *fsi);
 345static int sel_make_policycap(struct selinux_fs_info *fsi);
 346
 347/* declaration for sel_make_class_dirs */
 348static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
 349                        unsigned long *ino);
 350
 351static ssize_t sel_read_mls(struct file *filp, char __user *buf,
 352                                size_t count, loff_t *ppos)
 353{
 354        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 355        char tmpbuf[TMPBUFLEN];
 356        ssize_t length;
 357
 358        length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 359                           security_mls_enabled(fsi->state));
 360        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 361}
 362
 363static const struct file_operations sel_mls_ops = {
 364        .read           = sel_read_mls,
 365        .llseek         = generic_file_llseek,
 366};
 367
 368struct policy_load_memory {
 369        size_t len;
 370        void *data;
 371};
 372
 373static int sel_open_policy(struct inode *inode, struct file *filp)
 374{
 375        struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
 376        struct selinux_state *state = fsi->state;
 377        struct policy_load_memory *plm = NULL;
 378        int rc;
 379
 380        BUG_ON(filp->private_data);
 381
 382        mutex_lock(&fsi->mutex);
 383
 384        rc = avc_has_perm(&selinux_state,
 385                          current_sid(), SECINITSID_SECURITY,
 386                          SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 387        if (rc)
 388                goto err;
 389
 390        rc = -EBUSY;
 391        if (fsi->policy_opened)
 392                goto err;
 393
 394        rc = -ENOMEM;
 395        plm = kzalloc(sizeof(*plm), GFP_KERNEL);
 396        if (!plm)
 397                goto err;
 398
 399        if (i_size_read(inode) != security_policydb_len(state)) {
 400                inode_lock(inode);
 401                i_size_write(inode, security_policydb_len(state));
 402                inode_unlock(inode);
 403        }
 404
 405        rc = security_read_policy(state, &plm->data, &plm->len);
 406        if (rc)
 407                goto err;
 408
 409        fsi->policy_opened = 1;
 410
 411        filp->private_data = plm;
 412
 413        mutex_unlock(&fsi->mutex);
 414
 415        return 0;
 416err:
 417        mutex_unlock(&fsi->mutex);
 418
 419        if (plm)
 420                vfree(plm->data);
 421        kfree(plm);
 422        return rc;
 423}
 424
 425static int sel_release_policy(struct inode *inode, struct file *filp)
 426{
 427        struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
 428        struct policy_load_memory *plm = filp->private_data;
 429
 430        BUG_ON(!plm);
 431
 432        fsi->policy_opened = 0;
 433
 434        vfree(plm->data);
 435        kfree(plm);
 436
 437        return 0;
 438}
 439
 440static ssize_t sel_read_policy(struct file *filp, char __user *buf,
 441                               size_t count, loff_t *ppos)
 442{
 443        struct policy_load_memory *plm = filp->private_data;
 444        int ret;
 445
 446        ret = avc_has_perm(&selinux_state,
 447                           current_sid(), SECINITSID_SECURITY,
 448                          SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 449        if (ret)
 450                return ret;
 451
 452        return simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
 453}
 454
 455static vm_fault_t sel_mmap_policy_fault(struct vm_fault *vmf)
 456{
 457        struct policy_load_memory *plm = vmf->vma->vm_file->private_data;
 458        unsigned long offset;
 459        struct page *page;
 460
 461        if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
 462                return VM_FAULT_SIGBUS;
 463
 464        offset = vmf->pgoff << PAGE_SHIFT;
 465        if (offset >= roundup(plm->len, PAGE_SIZE))
 466                return VM_FAULT_SIGBUS;
 467
 468        page = vmalloc_to_page(plm->data + offset);
 469        get_page(page);
 470
 471        vmf->page = page;
 472
 473        return 0;
 474}
 475
 476static const struct vm_operations_struct sel_mmap_policy_ops = {
 477        .fault = sel_mmap_policy_fault,
 478        .page_mkwrite = sel_mmap_policy_fault,
 479};
 480
 481static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
 482{
 483        if (vma->vm_flags & VM_SHARED) {
 484                /* do not allow mprotect to make mapping writable */
 485                vma->vm_flags &= ~VM_MAYWRITE;
 486
 487                if (vma->vm_flags & VM_WRITE)
 488                        return -EACCES;
 489        }
 490
 491        vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 492        vma->vm_ops = &sel_mmap_policy_ops;
 493
 494        return 0;
 495}
 496
 497static const struct file_operations sel_policy_ops = {
 498        .open           = sel_open_policy,
 499        .read           = sel_read_policy,
 500        .mmap           = sel_mmap_policy,
 501        .release        = sel_release_policy,
 502        .llseek         = generic_file_llseek,
 503};
 504
 505static int sel_make_policy_nodes(struct selinux_fs_info *fsi)
 506{
 507        int ret;
 508
 509        ret = sel_make_bools(fsi);
 510        if (ret) {
 511                pr_err("SELinux: failed to load policy booleans\n");
 512                return ret;
 513        }
 514
 515        ret = sel_make_classes(fsi);
 516        if (ret) {
 517                pr_err("SELinux: failed to load policy classes\n");
 518                return ret;
 519        }
 520
 521        ret = sel_make_policycap(fsi);
 522        if (ret) {
 523                pr_err("SELinux: failed to load policy capabilities\n");
 524                return ret;
 525        }
 526
 527        return 0;
 528}
 529
 530static ssize_t sel_write_load(struct file *file, const char __user *buf,
 531                              size_t count, loff_t *ppos)
 532
 533{
 534        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 535        ssize_t length;
 536        void *data = NULL;
 537
 538        mutex_lock(&fsi->mutex);
 539
 540        length = avc_has_perm(&selinux_state,
 541                              current_sid(), SECINITSID_SECURITY,
 542                              SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
 543        if (length)
 544                goto out;
 545
 546        /* No partial writes. */
 547        length = -EINVAL;
 548        if (*ppos != 0)
 549                goto out;
 550
 551        length = -EFBIG;
 552        if (count > 64 * 1024 * 1024)
 553                goto out;
 554
 555        length = -ENOMEM;
 556        data = vmalloc(count);
 557        if (!data)
 558                goto out;
 559
 560        length = -EFAULT;
 561        if (copy_from_user(data, buf, count) != 0)
 562                goto out;
 563
 564        length = security_load_policy(fsi->state, data, count);
 565        if (length) {
 566                pr_warn_ratelimited("SELinux: failed to load policy\n");
 567                goto out;
 568        }
 569
 570        length = sel_make_policy_nodes(fsi);
 571        if (length)
 572                goto out1;
 573
 574        length = count;
 575
 576out1:
 577        audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
 578                "auid=%u ses=%u lsm=selinux res=1",
 579                from_kuid(&init_user_ns, audit_get_loginuid(current)),
 580                audit_get_sessionid(current));
 581out:
 582        mutex_unlock(&fsi->mutex);
 583        vfree(data);
 584        return length;
 585}
 586
 587static const struct file_operations sel_load_ops = {
 588        .write          = sel_write_load,
 589        .llseek         = generic_file_llseek,
 590};
 591
 592static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
 593{
 594        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 595        struct selinux_state *state = fsi->state;
 596        char *canon = NULL;
 597        u32 sid, len;
 598        ssize_t length;
 599
 600        length = avc_has_perm(&selinux_state,
 601                              current_sid(), SECINITSID_SECURITY,
 602                              SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
 603        if (length)
 604                goto out;
 605
 606        length = security_context_to_sid(state, buf, size, &sid, GFP_KERNEL);
 607        if (length)
 608                goto out;
 609
 610        length = security_sid_to_context(state, sid, &canon, &len);
 611        if (length)
 612                goto out;
 613
 614        length = -ERANGE;
 615        if (len > SIMPLE_TRANSACTION_LIMIT) {
 616                pr_err("SELinux: %s:  context size (%u) exceeds "
 617                        "payload max\n", __func__, len);
 618                goto out;
 619        }
 620
 621        memcpy(buf, canon, len);
 622        length = len;
 623out:
 624        kfree(canon);
 625        return length;
 626}
 627
 628static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
 629                                     size_t count, loff_t *ppos)
 630{
 631        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 632        char tmpbuf[TMPBUFLEN];
 633        ssize_t length;
 634
 635        length = scnprintf(tmpbuf, TMPBUFLEN, "%u", fsi->state->checkreqprot);
 636        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 637}
 638
 639static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
 640                                      size_t count, loff_t *ppos)
 641{
 642        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 643        char *page;
 644        ssize_t length;
 645        unsigned int new_value;
 646
 647        length = avc_has_perm(&selinux_state,
 648                              current_sid(), SECINITSID_SECURITY,
 649                              SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
 650                              NULL);
 651        if (length)
 652                return length;
 653
 654        if (count >= PAGE_SIZE)
 655                return -ENOMEM;
 656
 657        /* No partial writes. */
 658        if (*ppos != 0)
 659                return -EINVAL;
 660
 661        page = memdup_user_nul(buf, count);
 662        if (IS_ERR(page))
 663                return PTR_ERR(page);
 664
 665        length = -EINVAL;
 666        if (sscanf(page, "%u", &new_value) != 1)
 667                goto out;
 668
 669        fsi->state->checkreqprot = new_value ? 1 : 0;
 670        length = count;
 671out:
 672        kfree(page);
 673        return length;
 674}
 675static const struct file_operations sel_checkreqprot_ops = {
 676        .read           = sel_read_checkreqprot,
 677        .write          = sel_write_checkreqprot,
 678        .llseek         = generic_file_llseek,
 679};
 680
 681static ssize_t sel_write_validatetrans(struct file *file,
 682                                        const char __user *buf,
 683                                        size_t count, loff_t *ppos)
 684{
 685        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 686        struct selinux_state *state = fsi->state;
 687        char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
 688        char *req = NULL;
 689        u32 osid, nsid, tsid;
 690        u16 tclass;
 691        int rc;
 692
 693        rc = avc_has_perm(&selinux_state,
 694                          current_sid(), SECINITSID_SECURITY,
 695                          SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
 696        if (rc)
 697                goto out;
 698
 699        rc = -ENOMEM;
 700        if (count >= PAGE_SIZE)
 701                goto out;
 702
 703        /* No partial writes. */
 704        rc = -EINVAL;
 705        if (*ppos != 0)
 706                goto out;
 707
 708        req = memdup_user_nul(buf, count);
 709        if (IS_ERR(req)) {
 710                rc = PTR_ERR(req);
 711                req = NULL;
 712                goto out;
 713        }
 714
 715        rc = -ENOMEM;
 716        oldcon = kzalloc(count + 1, GFP_KERNEL);
 717        if (!oldcon)
 718                goto out;
 719
 720        newcon = kzalloc(count + 1, GFP_KERNEL);
 721        if (!newcon)
 722                goto out;
 723
 724        taskcon = kzalloc(count + 1, GFP_KERNEL);
 725        if (!taskcon)
 726                goto out;
 727
 728        rc = -EINVAL;
 729        if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
 730                goto out;
 731
 732        rc = security_context_str_to_sid(state, oldcon, &osid, GFP_KERNEL);
 733        if (rc)
 734                goto out;
 735
 736        rc = security_context_str_to_sid(state, newcon, &nsid, GFP_KERNEL);
 737        if (rc)
 738                goto out;
 739
 740        rc = security_context_str_to_sid(state, taskcon, &tsid, GFP_KERNEL);
 741        if (rc)
 742                goto out;
 743
 744        rc = security_validate_transition_user(state, osid, nsid, tsid, tclass);
 745        if (!rc)
 746                rc = count;
 747out:
 748        kfree(req);
 749        kfree(oldcon);
 750        kfree(newcon);
 751        kfree(taskcon);
 752        return rc;
 753}
 754
 755static const struct file_operations sel_transition_ops = {
 756        .write          = sel_write_validatetrans,
 757        .llseek         = generic_file_llseek,
 758};
 759
 760/*
 761 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 762 */
 763static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
 764static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
 765static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
 766static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
 767static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
 768
 769static ssize_t (*const write_op[])(struct file *, char *, size_t) = {
 770        [SEL_ACCESS] = sel_write_access,
 771        [SEL_CREATE] = sel_write_create,
 772        [SEL_RELABEL] = sel_write_relabel,
 773        [SEL_USER] = sel_write_user,
 774        [SEL_MEMBER] = sel_write_member,
 775        [SEL_CONTEXT] = sel_write_context,
 776};
 777
 778static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 779{
 780        ino_t ino = file_inode(file)->i_ino;
 781        char *data;
 782        ssize_t rv;
 783
 784        if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
 785                return -EINVAL;
 786
 787        data = simple_transaction_get(file, buf, size);
 788        if (IS_ERR(data))
 789                return PTR_ERR(data);
 790
 791        rv = write_op[ino](file, data, size);
 792        if (rv > 0) {
 793                simple_transaction_set(file, rv);
 794                rv = size;
 795        }
 796        return rv;
 797}
 798
 799static const struct file_operations transaction_ops = {
 800        .write          = selinux_transaction_write,
 801        .read           = simple_transaction_read,
 802        .release        = simple_transaction_release,
 803        .llseek         = generic_file_llseek,
 804};
 805
 806/*
 807 * payload - write methods
 808 * If the method has a response, the response should be put in buf,
 809 * and the length returned.  Otherwise return 0 or and -error.
 810 */
 811
 812static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
 813{
 814        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 815        struct selinux_state *state = fsi->state;
 816        char *scon = NULL, *tcon = NULL;
 817        u32 ssid, tsid;
 818        u16 tclass;
 819        struct av_decision avd;
 820        ssize_t length;
 821
 822        length = avc_has_perm(&selinux_state,
 823                              current_sid(), SECINITSID_SECURITY,
 824                              SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
 825        if (length)
 826                goto out;
 827
 828        length = -ENOMEM;
 829        scon = kzalloc(size + 1, GFP_KERNEL);
 830        if (!scon)
 831                goto out;
 832
 833        length = -ENOMEM;
 834        tcon = kzalloc(size + 1, GFP_KERNEL);
 835        if (!tcon)
 836                goto out;
 837
 838        length = -EINVAL;
 839        if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 840                goto out;
 841
 842        length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
 843        if (length)
 844                goto out;
 845
 846        length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
 847        if (length)
 848                goto out;
 849
 850        security_compute_av_user(state, ssid, tsid, tclass, &avd);
 851
 852        length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 853                          "%x %x %x %x %u %x",
 854                          avd.allowed, 0xffffffff,
 855                          avd.auditallow, avd.auditdeny,
 856                          avd.seqno, avd.flags);
 857out:
 858        kfree(tcon);
 859        kfree(scon);
 860        return length;
 861}
 862
 863static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
 864{
 865        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 866        struct selinux_state *state = fsi->state;
 867        char *scon = NULL, *tcon = NULL;
 868        char *namebuf = NULL, *objname = NULL;
 869        u32 ssid, tsid, newsid;
 870        u16 tclass;
 871        ssize_t length;
 872        char *newcon = NULL;
 873        u32 len;
 874        int nargs;
 875
 876        length = avc_has_perm(&selinux_state,
 877                              current_sid(), SECINITSID_SECURITY,
 878                              SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
 879                              NULL);
 880        if (length)
 881                goto out;
 882
 883        length = -ENOMEM;
 884        scon = kzalloc(size + 1, GFP_KERNEL);
 885        if (!scon)
 886                goto out;
 887
 888        length = -ENOMEM;
 889        tcon = kzalloc(size + 1, GFP_KERNEL);
 890        if (!tcon)
 891                goto out;
 892
 893        length = -ENOMEM;
 894        namebuf = kzalloc(size + 1, GFP_KERNEL);
 895        if (!namebuf)
 896                goto out;
 897
 898        length = -EINVAL;
 899        nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
 900        if (nargs < 3 || nargs > 4)
 901                goto out;
 902        if (nargs == 4) {
 903                /*
 904                 * If and when the name of new object to be queried contains
 905                 * either whitespace or multibyte characters, they shall be
 906                 * encoded based on the percentage-encoding rule.
 907                 * If not encoded, the sscanf logic picks up only left-half
 908                 * of the supplied name; splitted by a whitespace unexpectedly.
 909                 */
 910                char   *r, *w;
 911                int     c1, c2;
 912
 913                r = w = namebuf;
 914                do {
 915                        c1 = *r++;
 916                        if (c1 == '+')
 917                                c1 = ' ';
 918                        else if (c1 == '%') {
 919                                c1 = hex_to_bin(*r++);
 920                                if (c1 < 0)
 921                                        goto out;
 922                                c2 = hex_to_bin(*r++);
 923                                if (c2 < 0)
 924                                        goto out;
 925                                c1 = (c1 << 4) | c2;
 926                        }
 927                        *w++ = c1;
 928                } while (c1 != '\0');
 929
 930                objname = namebuf;
 931        }
 932
 933        length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
 934        if (length)
 935                goto out;
 936
 937        length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
 938        if (length)
 939                goto out;
 940
 941        length = security_transition_sid_user(state, ssid, tsid, tclass,
 942                                              objname, &newsid);
 943        if (length)
 944                goto out;
 945
 946        length = security_sid_to_context(state, newsid, &newcon, &len);
 947        if (length)
 948                goto out;
 949
 950        length = -ERANGE;
 951        if (len > SIMPLE_TRANSACTION_LIMIT) {
 952                pr_err("SELinux: %s:  context size (%u) exceeds "
 953                        "payload max\n", __func__, len);
 954                goto out;
 955        }
 956
 957        memcpy(buf, newcon, len);
 958        length = len;
 959out:
 960        kfree(newcon);
 961        kfree(namebuf);
 962        kfree(tcon);
 963        kfree(scon);
 964        return length;
 965}
 966
 967static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
 968{
 969        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 970        struct selinux_state *state = fsi->state;
 971        char *scon = NULL, *tcon = NULL;
 972        u32 ssid, tsid, newsid;
 973        u16 tclass;
 974        ssize_t length;
 975        char *newcon = NULL;
 976        u32 len;
 977
 978        length = avc_has_perm(&selinux_state,
 979                              current_sid(), SECINITSID_SECURITY,
 980                              SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
 981                              NULL);
 982        if (length)
 983                goto out;
 984
 985        length = -ENOMEM;
 986        scon = kzalloc(size + 1, GFP_KERNEL);
 987        if (!scon)
 988                goto out;
 989
 990        length = -ENOMEM;
 991        tcon = kzalloc(size + 1, GFP_KERNEL);
 992        if (!tcon)
 993                goto out;
 994
 995        length = -EINVAL;
 996        if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 997                goto out;
 998
 999        length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
1000        if (length)
1001                goto out;
1002
1003        length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1004        if (length)
1005                goto out;
1006
1007        length = security_change_sid(state, ssid, tsid, tclass, &newsid);
1008        if (length)
1009                goto out;
1010
1011        length = security_sid_to_context(state, newsid, &newcon, &len);
1012        if (length)
1013                goto out;
1014
1015        length = -ERANGE;
1016        if (len > SIMPLE_TRANSACTION_LIMIT)
1017                goto out;
1018
1019        memcpy(buf, newcon, len);
1020        length = len;
1021out:
1022        kfree(newcon);
1023        kfree(tcon);
1024        kfree(scon);
1025        return length;
1026}
1027
1028static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
1029{
1030        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1031        struct selinux_state *state = fsi->state;
1032        char *con = NULL, *user = NULL, *ptr;
1033        u32 sid, *sids = NULL;
1034        ssize_t length;
1035        char *newcon;
1036        int i, rc;
1037        u32 len, nsids;
1038
1039        length = avc_has_perm(&selinux_state,
1040                              current_sid(), SECINITSID_SECURITY,
1041                              SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
1042                              NULL);
1043        if (length)
1044                goto out;
1045
1046        length = -ENOMEM;
1047        con = kzalloc(size + 1, GFP_KERNEL);
1048        if (!con)
1049                goto out;
1050
1051        length = -ENOMEM;
1052        user = kzalloc(size + 1, GFP_KERNEL);
1053        if (!user)
1054                goto out;
1055
1056        length = -EINVAL;
1057        if (sscanf(buf, "%s %s", con, user) != 2)
1058                goto out;
1059
1060        length = security_context_str_to_sid(state, con, &sid, GFP_KERNEL);
1061        if (length)
1062                goto out;
1063
1064        length = security_get_user_sids(state, sid, user, &sids, &nsids);
1065        if (length)
1066                goto out;
1067
1068        length = sprintf(buf, "%u", nsids) + 1;
1069        ptr = buf + length;
1070        for (i = 0; i < nsids; i++) {
1071                rc = security_sid_to_context(state, sids[i], &newcon, &len);
1072                if (rc) {
1073                        length = rc;
1074                        goto out;
1075                }
1076                if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1077                        kfree(newcon);
1078                        length = -ERANGE;
1079                        goto out;
1080                }
1081                memcpy(ptr, newcon, len);
1082                kfree(newcon);
1083                ptr += len;
1084                length += len;
1085        }
1086out:
1087        kfree(sids);
1088        kfree(user);
1089        kfree(con);
1090        return length;
1091}
1092
1093static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1094{
1095        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1096        struct selinux_state *state = fsi->state;
1097        char *scon = NULL, *tcon = NULL;
1098        u32 ssid, tsid, newsid;
1099        u16 tclass;
1100        ssize_t length;
1101        char *newcon = NULL;
1102        u32 len;
1103
1104        length = avc_has_perm(&selinux_state,
1105                              current_sid(), SECINITSID_SECURITY,
1106                              SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
1107                              NULL);
1108        if (length)
1109                goto out;
1110
1111        length = -ENOMEM;
1112        scon = kzalloc(size + 1, GFP_KERNEL);
1113        if (!scon)
1114                goto out;
1115
1116        length = -ENOMEM;
1117        tcon = kzalloc(size + 1, GFP_KERNEL);
1118        if (!tcon)
1119                goto out;
1120
1121        length = -EINVAL;
1122        if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1123                goto out;
1124
1125        length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
1126        if (length)
1127                goto out;
1128
1129        length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1130        if (length)
1131                goto out;
1132
1133        length = security_member_sid(state, ssid, tsid, tclass, &newsid);
1134        if (length)
1135                goto out;
1136
1137        length = security_sid_to_context(state, newsid, &newcon, &len);
1138        if (length)
1139                goto out;
1140
1141        length = -ERANGE;
1142        if (len > SIMPLE_TRANSACTION_LIMIT) {
1143                pr_err("SELinux: %s:  context size (%u) exceeds "
1144                        "payload max\n", __func__, len);
1145                goto out;
1146        }
1147
1148        memcpy(buf, newcon, len);
1149        length = len;
1150out:
1151        kfree(newcon);
1152        kfree(tcon);
1153        kfree(scon);
1154        return length;
1155}
1156
1157static struct inode *sel_make_inode(struct super_block *sb, int mode)
1158{
1159        struct inode *ret = new_inode(sb);
1160
1161        if (ret) {
1162                ret->i_mode = mode;
1163                ret->i_atime = ret->i_mtime = ret->i_ctime = current_time(ret);
1164        }
1165        return ret;
1166}
1167
1168static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1169                             size_t count, loff_t *ppos)
1170{
1171        struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1172        char *page = NULL;
1173        ssize_t length;
1174        ssize_t ret;
1175        int cur_enforcing;
1176        unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1177        const char *name = filep->f_path.dentry->d_name.name;
1178
1179        mutex_lock(&fsi->mutex);
1180
1181        ret = -EINVAL;
1182        if (index >= fsi->bool_num || strcmp(name,
1183                                             fsi->bool_pending_names[index]))
1184                goto out_unlock;
1185
1186        ret = -ENOMEM;
1187        page = (char *)get_zeroed_page(GFP_KERNEL);
1188        if (!page)
1189                goto out_unlock;
1190
1191        cur_enforcing = security_get_bool_value(fsi->state, index);
1192        if (cur_enforcing < 0) {
1193                ret = cur_enforcing;
1194                goto out_unlock;
1195        }
1196        length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1197                          fsi->bool_pending_values[index]);
1198        mutex_unlock(&fsi->mutex);
1199        ret = simple_read_from_buffer(buf, count, ppos, page, length);
1200out_free:
1201        free_page((unsigned long)page);
1202        return ret;
1203
1204out_unlock:
1205        mutex_unlock(&fsi->mutex);
1206        goto out_free;
1207}
1208
1209static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1210                              size_t count, loff_t *ppos)
1211{
1212        struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1213        char *page = NULL;
1214        ssize_t length;
1215        int new_value;
1216        unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1217        const char *name = filep->f_path.dentry->d_name.name;
1218
1219        if (count >= PAGE_SIZE)
1220                return -ENOMEM;
1221
1222        /* No partial writes. */
1223        if (*ppos != 0)
1224                return -EINVAL;
1225
1226        page = memdup_user_nul(buf, count);
1227        if (IS_ERR(page))
1228                return PTR_ERR(page);
1229
1230        mutex_lock(&fsi->mutex);
1231
1232        length = avc_has_perm(&selinux_state,
1233                              current_sid(), SECINITSID_SECURITY,
1234                              SECCLASS_SECURITY, SECURITY__SETBOOL,
1235                              NULL);
1236        if (length)
1237                goto out;
1238
1239        length = -EINVAL;
1240        if (index >= fsi->bool_num || strcmp(name,
1241                                             fsi->bool_pending_names[index]))
1242                goto out;
1243
1244        length = -EINVAL;
1245        if (sscanf(page, "%d", &new_value) != 1)
1246                goto out;
1247
1248        if (new_value)
1249                new_value = 1;
1250
1251        fsi->bool_pending_values[index] = new_value;
1252        length = count;
1253
1254out:
1255        mutex_unlock(&fsi->mutex);
1256        kfree(page);
1257        return length;
1258}
1259
1260static const struct file_operations sel_bool_ops = {
1261        .read           = sel_read_bool,
1262        .write          = sel_write_bool,
1263        .llseek         = generic_file_llseek,
1264};
1265
1266static ssize_t sel_commit_bools_write(struct file *filep,
1267                                      const char __user *buf,
1268                                      size_t count, loff_t *ppos)
1269{
1270        struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1271        char *page = NULL;
1272        ssize_t length;
1273        int new_value;
1274
1275        if (count >= PAGE_SIZE)
1276                return -ENOMEM;
1277
1278        /* No partial writes. */
1279        if (*ppos != 0)
1280                return -EINVAL;
1281
1282        page = memdup_user_nul(buf, count);
1283        if (IS_ERR(page))
1284                return PTR_ERR(page);
1285
1286        mutex_lock(&fsi->mutex);
1287
1288        length = avc_has_perm(&selinux_state,
1289                              current_sid(), SECINITSID_SECURITY,
1290                              SECCLASS_SECURITY, SECURITY__SETBOOL,
1291                              NULL);
1292        if (length)
1293                goto out;
1294
1295        length = -EINVAL;
1296        if (sscanf(page, "%d", &new_value) != 1)
1297                goto out;
1298
1299        length = 0;
1300        if (new_value && fsi->bool_pending_values)
1301                length = security_set_bools(fsi->state, fsi->bool_num,
1302                                            fsi->bool_pending_values);
1303
1304        if (!length)
1305                length = count;
1306
1307out:
1308        mutex_unlock(&fsi->mutex);
1309        kfree(page);
1310        return length;
1311}
1312
1313static const struct file_operations sel_commit_bools_ops = {
1314        .write          = sel_commit_bools_write,
1315        .llseek         = generic_file_llseek,
1316};
1317
1318static void sel_remove_entries(struct dentry *de)
1319{
1320        d_genocide(de);
1321        shrink_dcache_parent(de);
1322}
1323
1324#define BOOL_DIR_NAME "booleans"
1325
1326static int sel_make_bools(struct selinux_fs_info *fsi)
1327{
1328        int i, ret;
1329        ssize_t len;
1330        struct dentry *dentry = NULL;
1331        struct dentry *dir = fsi->bool_dir;
1332        struct inode *inode = NULL;
1333        struct inode_security_struct *isec;
1334        char **names = NULL, *page;
1335        int num;
1336        int *values = NULL;
1337        u32 sid;
1338
1339        /* remove any existing files */
1340        for (i = 0; i < fsi->bool_num; i++)
1341                kfree(fsi->bool_pending_names[i]);
1342        kfree(fsi->bool_pending_names);
1343        kfree(fsi->bool_pending_values);
1344        fsi->bool_num = 0;
1345        fsi->bool_pending_names = NULL;
1346        fsi->bool_pending_values = NULL;
1347
1348        sel_remove_entries(dir);
1349
1350        ret = -ENOMEM;
1351        page = (char *)get_zeroed_page(GFP_KERNEL);
1352        if (!page)
1353                goto out;
1354
1355        ret = security_get_bools(fsi->state, &num, &names, &values);
1356        if (ret)
1357                goto out;
1358
1359        for (i = 0; i < num; i++) {
1360                ret = -ENOMEM;
1361                dentry = d_alloc_name(dir, names[i]);
1362                if (!dentry)
1363                        goto out;
1364
1365                ret = -ENOMEM;
1366                inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1367                if (!inode) {
1368                        dput(dentry);
1369                        goto out;
1370                }
1371
1372                ret = -ENAMETOOLONG;
1373                len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1374                if (len >= PAGE_SIZE) {
1375                        dput(dentry);
1376                        iput(inode);
1377                        goto out;
1378                }
1379
1380                isec = selinux_inode(inode);
1381                ret = security_genfs_sid(fsi->state, "selinuxfs", page,
1382                                         SECCLASS_FILE, &sid);
1383                if (ret) {
1384                        pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
1385                                           page);
1386                        sid = SECINITSID_SECURITY;
1387                }
1388
1389                isec->sid = sid;
1390                isec->initialized = LABEL_INITIALIZED;
1391                inode->i_fop = &sel_bool_ops;
1392                inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1393                d_add(dentry, inode);
1394        }
1395        fsi->bool_num = num;
1396        fsi->bool_pending_names = names;
1397        fsi->bool_pending_values = values;
1398
1399        free_page((unsigned long)page);
1400        return 0;
1401out:
1402        free_page((unsigned long)page);
1403
1404        if (names) {
1405                for (i = 0; i < num; i++)
1406                        kfree(names[i]);
1407                kfree(names);
1408        }
1409        kfree(values);
1410        sel_remove_entries(dir);
1411
1412        return ret;
1413}
1414
1415static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1416                                            size_t count, loff_t *ppos)
1417{
1418        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1419        struct selinux_state *state = fsi->state;
1420        char tmpbuf[TMPBUFLEN];
1421        ssize_t length;
1422
1423        length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1424                           avc_get_cache_threshold(state->avc));
1425        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1426}
1427
1428static ssize_t sel_write_avc_cache_threshold(struct file *file,
1429                                             const char __user *buf,
1430                                             size_t count, loff_t *ppos)
1431
1432{
1433        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1434        struct selinux_state *state = fsi->state;
1435        char *page;
1436        ssize_t ret;
1437        unsigned int new_value;
1438
1439        ret = avc_has_perm(&selinux_state,
1440                           current_sid(), SECINITSID_SECURITY,
1441                           SECCLASS_SECURITY, SECURITY__SETSECPARAM,
1442                           NULL);
1443        if (ret)
1444                return ret;
1445
1446        if (count >= PAGE_SIZE)
1447                return -ENOMEM;
1448
1449        /* No partial writes. */
1450        if (*ppos != 0)
1451                return -EINVAL;
1452
1453        page = memdup_user_nul(buf, count);
1454        if (IS_ERR(page))
1455                return PTR_ERR(page);
1456
1457        ret = -EINVAL;
1458        if (sscanf(page, "%u", &new_value) != 1)
1459                goto out;
1460
1461        avc_set_cache_threshold(state->avc, new_value);
1462
1463        ret = count;
1464out:
1465        kfree(page);
1466        return ret;
1467}
1468
1469static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1470                                       size_t count, loff_t *ppos)
1471{
1472        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1473        struct selinux_state *state = fsi->state;
1474        char *page;
1475        ssize_t length;
1476
1477        page = (char *)__get_free_page(GFP_KERNEL);
1478        if (!page)
1479                return -ENOMEM;
1480
1481        length = avc_get_hash_stats(state->avc, page);
1482        if (length >= 0)
1483                length = simple_read_from_buffer(buf, count, ppos, page, length);
1484        free_page((unsigned long)page);
1485
1486        return length;
1487}
1488
1489static const struct file_operations sel_avc_cache_threshold_ops = {
1490        .read           = sel_read_avc_cache_threshold,
1491        .write          = sel_write_avc_cache_threshold,
1492        .llseek         = generic_file_llseek,
1493};
1494
1495static const struct file_operations sel_avc_hash_stats_ops = {
1496        .read           = sel_read_avc_hash_stats,
1497        .llseek         = generic_file_llseek,
1498};
1499
1500#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1501static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1502{
1503        int cpu;
1504
1505        for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1506                if (!cpu_possible(cpu))
1507                        continue;
1508                *idx = cpu + 1;
1509                return &per_cpu(avc_cache_stats, cpu);
1510        }
1511        return NULL;
1512}
1513
1514static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1515{
1516        loff_t n = *pos - 1;
1517
1518        if (*pos == 0)
1519                return SEQ_START_TOKEN;
1520
1521        return sel_avc_get_stat_idx(&n);
1522}
1523
1524static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1525{
1526        return sel_avc_get_stat_idx(pos);
1527}
1528
1529static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1530{
1531        struct avc_cache_stats *st = v;
1532
1533        if (v == SEQ_START_TOKEN) {
1534                seq_puts(seq,
1535                         "lookups hits misses allocations reclaims frees\n");
1536        } else {
1537                unsigned int lookups = st->lookups;
1538                unsigned int misses = st->misses;
1539                unsigned int hits = lookups - misses;
1540                seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1541                           hits, misses, st->allocations,
1542                           st->reclaims, st->frees);
1543        }
1544        return 0;
1545}
1546
1547static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1548{ }
1549
1550static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1551        .start          = sel_avc_stats_seq_start,
1552        .next           = sel_avc_stats_seq_next,
1553        .show           = sel_avc_stats_seq_show,
1554        .stop           = sel_avc_stats_seq_stop,
1555};
1556
1557static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1558{
1559        return seq_open(file, &sel_avc_cache_stats_seq_ops);
1560}
1561
1562static const struct file_operations sel_avc_cache_stats_ops = {
1563        .open           = sel_open_avc_cache_stats,
1564        .read           = seq_read,
1565        .llseek         = seq_lseek,
1566        .release        = seq_release,
1567};
1568#endif
1569
1570static int sel_make_avc_files(struct dentry *dir)
1571{
1572        struct super_block *sb = dir->d_sb;
1573        struct selinux_fs_info *fsi = sb->s_fs_info;
1574        int i;
1575        static const struct tree_descr files[] = {
1576                { "cache_threshold",
1577                  &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1578                { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1579#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1580                { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1581#endif
1582        };
1583
1584        for (i = 0; i < ARRAY_SIZE(files); i++) {
1585                struct inode *inode;
1586                struct dentry *dentry;
1587
1588                dentry = d_alloc_name(dir, files[i].name);
1589                if (!dentry)
1590                        return -ENOMEM;
1591
1592                inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1593                if (!inode) {
1594                        dput(dentry);
1595                        return -ENOMEM;
1596                }
1597
1598                inode->i_fop = files[i].ops;
1599                inode->i_ino = ++fsi->last_ino;
1600                d_add(dentry, inode);
1601        }
1602
1603        return 0;
1604}
1605
1606static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1607                                size_t count, loff_t *ppos)
1608{
1609        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1610        char *con;
1611        u32 sid, len;
1612        ssize_t ret;
1613
1614        sid = file_inode(file)->i_ino&SEL_INO_MASK;
1615        ret = security_sid_to_context(fsi->state, sid, &con, &len);
1616        if (ret)
1617                return ret;
1618
1619        ret = simple_read_from_buffer(buf, count, ppos, con, len);
1620        kfree(con);
1621        return ret;
1622}
1623
1624static const struct file_operations sel_initcon_ops = {
1625        .read           = sel_read_initcon,
1626        .llseek         = generic_file_llseek,
1627};
1628
1629static int sel_make_initcon_files(struct dentry *dir)
1630{
1631        int i;
1632
1633        for (i = 1; i <= SECINITSID_NUM; i++) {
1634                struct inode *inode;
1635                struct dentry *dentry;
1636                dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1637                if (!dentry)
1638                        return -ENOMEM;
1639
1640                inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1641                if (!inode) {
1642                        dput(dentry);
1643                        return -ENOMEM;
1644                }
1645
1646                inode->i_fop = &sel_initcon_ops;
1647                inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1648                d_add(dentry, inode);
1649        }
1650
1651        return 0;
1652}
1653
1654static inline unsigned long sel_class_to_ino(u16 class)
1655{
1656        return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1657}
1658
1659static inline u16 sel_ino_to_class(unsigned long ino)
1660{
1661        return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1662}
1663
1664static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1665{
1666        return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1667}
1668
1669static inline u32 sel_ino_to_perm(unsigned long ino)
1670{
1671        return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1672}
1673
1674static ssize_t sel_read_class(struct file *file, char __user *buf,
1675                                size_t count, loff_t *ppos)
1676{
1677        unsigned long ino = file_inode(file)->i_ino;
1678        char res[TMPBUFLEN];
1679        ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1680        return simple_read_from_buffer(buf, count, ppos, res, len);
1681}
1682
1683static const struct file_operations sel_class_ops = {
1684        .read           = sel_read_class,
1685        .llseek         = generic_file_llseek,
1686};
1687
1688static ssize_t sel_read_perm(struct file *file, char __user *buf,
1689                                size_t count, loff_t *ppos)
1690{
1691        unsigned long ino = file_inode(file)->i_ino;
1692        char res[TMPBUFLEN];
1693        ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1694        return simple_read_from_buffer(buf, count, ppos, res, len);
1695}
1696
1697static const struct file_operations sel_perm_ops = {
1698        .read           = sel_read_perm,
1699        .llseek         = generic_file_llseek,
1700};
1701
1702static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1703                                  size_t count, loff_t *ppos)
1704{
1705        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1706        int value;
1707        char tmpbuf[TMPBUFLEN];
1708        ssize_t length;
1709        unsigned long i_ino = file_inode(file)->i_ino;
1710
1711        value = security_policycap_supported(fsi->state, i_ino & SEL_INO_MASK);
1712        length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1713
1714        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1715}
1716
1717static const struct file_operations sel_policycap_ops = {
1718        .read           = sel_read_policycap,
1719        .llseek         = generic_file_llseek,
1720};
1721
1722static int sel_make_perm_files(char *objclass, int classvalue,
1723                                struct dentry *dir)
1724{
1725        struct selinux_fs_info *fsi = dir->d_sb->s_fs_info;
1726        int i, rc, nperms;
1727        char **perms;
1728
1729        rc = security_get_permissions(fsi->state, objclass, &perms, &nperms);
1730        if (rc)
1731                return rc;
1732
1733        for (i = 0; i < nperms; i++) {
1734                struct inode *inode;
1735                struct dentry *dentry;
1736
1737                rc = -ENOMEM;
1738                dentry = d_alloc_name(dir, perms[i]);
1739                if (!dentry)
1740                        goto out;
1741
1742                rc = -ENOMEM;
1743                inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1744                if (!inode) {
1745                        dput(dentry);
1746                        goto out;
1747                }
1748
1749                inode->i_fop = &sel_perm_ops;
1750                /* i+1 since perm values are 1-indexed */
1751                inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1752                d_add(dentry, inode);
1753        }
1754        rc = 0;
1755out:
1756        for (i = 0; i < nperms; i++)
1757                kfree(perms[i]);
1758        kfree(perms);
1759        return rc;
1760}
1761
1762static int sel_make_class_dir_entries(char *classname, int index,
1763                                        struct dentry *dir)
1764{
1765        struct super_block *sb = dir->d_sb;
1766        struct selinux_fs_info *fsi = sb->s_fs_info;
1767        struct dentry *dentry = NULL;
1768        struct inode *inode = NULL;
1769        int rc;
1770
1771        dentry = d_alloc_name(dir, "index");
1772        if (!dentry)
1773                return -ENOMEM;
1774
1775        inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1776        if (!inode) {
1777                dput(dentry);
1778                return -ENOMEM;
1779        }
1780
1781        inode->i_fop = &sel_class_ops;
1782        inode->i_ino = sel_class_to_ino(index);
1783        d_add(dentry, inode);
1784
1785        dentry = sel_make_dir(dir, "perms", &fsi->last_class_ino);
1786        if (IS_ERR(dentry))
1787                return PTR_ERR(dentry);
1788
1789        rc = sel_make_perm_files(classname, index, dentry);
1790
1791        return rc;
1792}
1793
1794static int sel_make_classes(struct selinux_fs_info *fsi)
1795{
1796
1797        int rc, nclasses, i;
1798        char **classes;
1799
1800        /* delete any existing entries */
1801        sel_remove_entries(fsi->class_dir);
1802
1803        rc = security_get_classes(fsi->state, &classes, &nclasses);
1804        if (rc)
1805                return rc;
1806
1807        /* +2 since classes are 1-indexed */
1808        fsi->last_class_ino = sel_class_to_ino(nclasses + 2);
1809
1810        for (i = 0; i < nclasses; i++) {
1811                struct dentry *class_name_dir;
1812
1813                class_name_dir = sel_make_dir(fsi->class_dir, classes[i],
1814                                              &fsi->last_class_ino);
1815                if (IS_ERR(class_name_dir)) {
1816                        rc = PTR_ERR(class_name_dir);
1817                        goto out;
1818                }
1819
1820                /* i+1 since class values are 1-indexed */
1821                rc = sel_make_class_dir_entries(classes[i], i + 1,
1822                                class_name_dir);
1823                if (rc)
1824                        goto out;
1825        }
1826        rc = 0;
1827out:
1828        for (i = 0; i < nclasses; i++)
1829                kfree(classes[i]);
1830        kfree(classes);
1831        return rc;
1832}
1833
1834static int sel_make_policycap(struct selinux_fs_info *fsi)
1835{
1836        unsigned int iter;
1837        struct dentry *dentry = NULL;
1838        struct inode *inode = NULL;
1839
1840        sel_remove_entries(fsi->policycap_dir);
1841
1842        for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1843                if (iter < ARRAY_SIZE(selinux_policycap_names))
1844                        dentry = d_alloc_name(fsi->policycap_dir,
1845                                              selinux_policycap_names[iter]);
1846                else
1847                        dentry = d_alloc_name(fsi->policycap_dir, "unknown");
1848
1849                if (dentry == NULL)
1850                        return -ENOMEM;
1851
1852                inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
1853                if (inode == NULL) {
1854                        dput(dentry);
1855                        return -ENOMEM;
1856                }
1857
1858                inode->i_fop = &sel_policycap_ops;
1859                inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1860                d_add(dentry, inode);
1861        }
1862
1863        return 0;
1864}
1865
1866static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1867                        unsigned long *ino)
1868{
1869        struct dentry *dentry = d_alloc_name(dir, name);
1870        struct inode *inode;
1871
1872        if (!dentry)
1873                return ERR_PTR(-ENOMEM);
1874
1875        inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1876        if (!inode) {
1877                dput(dentry);
1878                return ERR_PTR(-ENOMEM);
1879        }
1880
1881        inode->i_op = &simple_dir_inode_operations;
1882        inode->i_fop = &simple_dir_operations;
1883        inode->i_ino = ++(*ino);
1884        /* directory inodes start off with i_nlink == 2 (for "." entry) */
1885        inc_nlink(inode);
1886        d_add(dentry, inode);
1887        /* bump link count on parent directory, too */
1888        inc_nlink(d_inode(dir));
1889
1890        return dentry;
1891}
1892
1893#define NULL_FILE_NAME "null"
1894
1895static int sel_fill_super(struct super_block *sb, struct fs_context *fc)
1896{
1897        struct selinux_fs_info *fsi;
1898        int ret;
1899        struct dentry *dentry;
1900        struct inode *inode;
1901        struct inode_security_struct *isec;
1902
1903        static const struct tree_descr selinux_files[] = {
1904                [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1905                [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1906                [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1907                [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1908                [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1909                [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1910                [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1911                [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1912                [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1913                [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1914                [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1915                [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1916                [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1917                [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1918                [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1919                [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1920                [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
1921                [SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
1922                                        S_IWUGO},
1923                /* last one */ {""}
1924        };
1925
1926        ret = selinux_fs_info_create(sb);
1927        if (ret)
1928                goto err;
1929
1930        ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1931        if (ret)
1932                goto err;
1933
1934        fsi = sb->s_fs_info;
1935        fsi->bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &fsi->last_ino);
1936        if (IS_ERR(fsi->bool_dir)) {
1937                ret = PTR_ERR(fsi->bool_dir);
1938                fsi->bool_dir = NULL;
1939                goto err;
1940        }
1941
1942        ret = -ENOMEM;
1943        dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1944        if (!dentry)
1945                goto err;
1946
1947        ret = -ENOMEM;
1948        inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1949        if (!inode) {
1950                dput(dentry);
1951                goto err;
1952        }
1953
1954        inode->i_ino = ++fsi->last_ino;
1955        isec = selinux_inode(inode);
1956        isec->sid = SECINITSID_DEVNULL;
1957        isec->sclass = SECCLASS_CHR_FILE;
1958        isec->initialized = LABEL_INITIALIZED;
1959
1960        init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1961        d_add(dentry, inode);
1962
1963        dentry = sel_make_dir(sb->s_root, "avc", &fsi->last_ino);
1964        if (IS_ERR(dentry)) {
1965                ret = PTR_ERR(dentry);
1966                goto err;
1967        }
1968
1969        ret = sel_make_avc_files(dentry);
1970        if (ret)
1971                goto err;
1972
1973        dentry = sel_make_dir(sb->s_root, "initial_contexts", &fsi->last_ino);
1974        if (IS_ERR(dentry)) {
1975                ret = PTR_ERR(dentry);
1976                goto err;
1977        }
1978
1979        ret = sel_make_initcon_files(dentry);
1980        if (ret)
1981                goto err;
1982
1983        fsi->class_dir = sel_make_dir(sb->s_root, "class", &fsi->last_ino);
1984        if (IS_ERR(fsi->class_dir)) {
1985                ret = PTR_ERR(fsi->class_dir);
1986                fsi->class_dir = NULL;
1987                goto err;
1988        }
1989
1990        fsi->policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities",
1991                                          &fsi->last_ino);
1992        if (IS_ERR(fsi->policycap_dir)) {
1993                ret = PTR_ERR(fsi->policycap_dir);
1994                fsi->policycap_dir = NULL;
1995                goto err;
1996        }
1997
1998        ret = sel_make_policy_nodes(fsi);
1999        if (ret)
2000                goto err;
2001        return 0;
2002err:
2003        pr_err("SELinux: %s:  failed while creating inodes\n",
2004                __func__);
2005
2006        selinux_fs_info_free(sb);
2007
2008        return ret;
2009}
2010
2011static int sel_get_tree(struct fs_context *fc)
2012{
2013        return get_tree_single(fc, sel_fill_super);
2014}
2015
2016static const struct fs_context_operations sel_context_ops = {
2017        .get_tree       = sel_get_tree,
2018};
2019
2020static int sel_init_fs_context(struct fs_context *fc)
2021{
2022        fc->ops = &sel_context_ops;
2023        return 0;
2024}
2025
2026static void sel_kill_sb(struct super_block *sb)
2027{
2028        selinux_fs_info_free(sb);
2029        kill_litter_super(sb);
2030}
2031
2032static struct file_system_type sel_fs_type = {
2033        .name           = "selinuxfs",
2034        .init_fs_context = sel_init_fs_context,
2035        .kill_sb        = sel_kill_sb,
2036};
2037
2038struct vfsmount *selinuxfs_mount;
2039struct path selinux_null;
2040
2041static int __init init_sel_fs(void)
2042{
2043        struct qstr null_name = QSTR_INIT(NULL_FILE_NAME,
2044                                          sizeof(NULL_FILE_NAME)-1);
2045        int err;
2046
2047        if (!selinux_enabled)
2048                return 0;
2049
2050        err = sysfs_create_mount_point(fs_kobj, "selinux");
2051        if (err)
2052                return err;
2053
2054        err = register_filesystem(&sel_fs_type);
2055        if (err) {
2056                sysfs_remove_mount_point(fs_kobj, "selinux");
2057                return err;
2058        }
2059
2060        selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type);
2061        if (IS_ERR(selinuxfs_mount)) {
2062                pr_err("selinuxfs:  could not mount!\n");
2063                err = PTR_ERR(selinuxfs_mount);
2064                selinuxfs_mount = NULL;
2065        }
2066        selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root,
2067                                                &null_name);
2068        if (IS_ERR(selinux_null.dentry)) {
2069                pr_err("selinuxfs:  could not lookup null!\n");
2070                err = PTR_ERR(selinux_null.dentry);
2071                selinux_null.dentry = NULL;
2072        }
2073
2074        return err;
2075}
2076
2077__initcall(init_sel_fs);
2078
2079#ifdef CONFIG_SECURITY_SELINUX_DISABLE
2080void exit_sel_fs(void)
2081{
2082        sysfs_remove_mount_point(fs_kobj, "selinux");
2083        dput(selinux_null.dentry);
2084        kern_unmount(selinuxfs_mount);
2085        unregister_filesystem(&sel_fs_type);
2086}
2087#endif
2088