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=1 old-enabled=1 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                enforcing_set(state, new_value);
 176                if (new_value)
 177                        avc_ss_reset(state->avc, 0);
 178                selnl_notify_setenforce(new_value);
 179                selinux_status_update_setenforce(state, new_value);
 180                if (!new_value)
 181                        call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 182        }
 183        length = count;
 184out:
 185        kfree(page);
 186        return length;
 187}
 188#else
 189#define sel_write_enforce NULL
 190#endif
 191
 192static const struct file_operations sel_enforce_ops = {
 193        .read           = sel_read_enforce,
 194        .write          = sel_write_enforce,
 195        .llseek         = generic_file_llseek,
 196};
 197
 198static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
 199                                        size_t count, loff_t *ppos)
 200{
 201        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 202        struct selinux_state *state = fsi->state;
 203        char tmpbuf[TMPBUFLEN];
 204        ssize_t length;
 205        ino_t ino = file_inode(filp)->i_ino;
 206        int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
 207                security_get_reject_unknown(state) :
 208                !security_get_allow_unknown(state);
 209
 210        length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
 211        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 212}
 213
 214static const struct file_operations sel_handle_unknown_ops = {
 215        .read           = sel_read_handle_unknown,
 216        .llseek         = generic_file_llseek,
 217};
 218
 219static int sel_open_handle_status(struct inode *inode, struct file *filp)
 220{
 221        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 222        struct page    *status = selinux_kernel_status_page(fsi->state);
 223
 224        if (!status)
 225                return -ENOMEM;
 226
 227        filp->private_data = status;
 228
 229        return 0;
 230}
 231
 232static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
 233                                      size_t count, loff_t *ppos)
 234{
 235        struct page    *status = filp->private_data;
 236
 237        BUG_ON(!status);
 238
 239        return simple_read_from_buffer(buf, count, ppos,
 240                                       page_address(status),
 241                                       sizeof(struct selinux_kernel_status));
 242}
 243
 244static int sel_mmap_handle_status(struct file *filp,
 245                                  struct vm_area_struct *vma)
 246{
 247        struct page    *status = filp->private_data;
 248        unsigned long   size = vma->vm_end - vma->vm_start;
 249
 250        BUG_ON(!status);
 251
 252        /* only allows one page from the head */
 253        if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
 254                return -EIO;
 255        /* disallow writable mapping */
 256        if (vma->vm_flags & VM_WRITE)
 257                return -EPERM;
 258        /* disallow mprotect() turns it into writable */
 259        vma->vm_flags &= ~VM_MAYWRITE;
 260
 261        return remap_pfn_range(vma, vma->vm_start,
 262                               page_to_pfn(status),
 263                               size, vma->vm_page_prot);
 264}
 265
 266static const struct file_operations sel_handle_status_ops = {
 267        .open           = sel_open_handle_status,
 268        .read           = sel_read_handle_status,
 269        .mmap           = sel_mmap_handle_status,
 270        .llseek         = generic_file_llseek,
 271};
 272
 273#ifdef CONFIG_SECURITY_SELINUX_DISABLE
 274static ssize_t sel_write_disable(struct file *file, const char __user *buf,
 275                                 size_t count, loff_t *ppos)
 276
 277{
 278        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 279        char *page;
 280        ssize_t length;
 281        int new_value;
 282        int enforcing;
 283
 284        /* NOTE: we are now officially considering runtime disable as
 285         *       deprecated, and using it will become increasingly painful
 286         *       (e.g. sleeping/blocking) as we progress through future
 287         *       kernel releases until eventually it is removed
 288         */
 289        pr_err("SELinux:  Runtime disable is deprecated, use selinux=0 on the kernel cmdline.\n");
 290
 291        if (count >= PAGE_SIZE)
 292                return -ENOMEM;
 293
 294        /* No partial writes. */
 295        if (*ppos != 0)
 296                return -EINVAL;
 297
 298        page = memdup_user_nul(buf, count);
 299        if (IS_ERR(page))
 300                return PTR_ERR(page);
 301
 302        length = -EINVAL;
 303        if (sscanf(page, "%d", &new_value) != 1)
 304                goto out;
 305
 306        if (new_value) {
 307                enforcing = enforcing_enabled(fsi->state);
 308                length = selinux_disable(fsi->state);
 309                if (length)
 310                        goto out;
 311                audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
 312                        "enforcing=%d old_enforcing=%d auid=%u ses=%u"
 313                        " enabled=0 old-enabled=1 lsm=selinux res=1",
 314                        enforcing, enforcing,
 315                        from_kuid(&init_user_ns, audit_get_loginuid(current)),
 316                        audit_get_sessionid(current));
 317        }
 318
 319        length = count;
 320out:
 321        kfree(page);
 322        return length;
 323}
 324#else
 325#define sel_write_disable NULL
 326#endif
 327
 328static const struct file_operations sel_disable_ops = {
 329        .write          = sel_write_disable,
 330        .llseek         = generic_file_llseek,
 331};
 332
 333static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
 334                                   size_t count, loff_t *ppos)
 335{
 336        char tmpbuf[TMPBUFLEN];
 337        ssize_t length;
 338
 339        length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
 340        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 341}
 342
 343static const struct file_operations sel_policyvers_ops = {
 344        .read           = sel_read_policyvers,
 345        .llseek         = generic_file_llseek,
 346};
 347
 348/* declaration for sel_write_load */
 349static int sel_make_bools(struct selinux_fs_info *fsi);
 350static int sel_make_classes(struct selinux_fs_info *fsi);
 351static int sel_make_policycap(struct selinux_fs_info *fsi);
 352
 353/* declaration for sel_make_class_dirs */
 354static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
 355                        unsigned long *ino);
 356
 357static ssize_t sel_read_mls(struct file *filp, char __user *buf,
 358                                size_t count, loff_t *ppos)
 359{
 360        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 361        char tmpbuf[TMPBUFLEN];
 362        ssize_t length;
 363
 364        length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 365                           security_mls_enabled(fsi->state));
 366        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 367}
 368
 369static const struct file_operations sel_mls_ops = {
 370        .read           = sel_read_mls,
 371        .llseek         = generic_file_llseek,
 372};
 373
 374struct policy_load_memory {
 375        size_t len;
 376        void *data;
 377};
 378
 379static int sel_open_policy(struct inode *inode, struct file *filp)
 380{
 381        struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
 382        struct selinux_state *state = fsi->state;
 383        struct policy_load_memory *plm = NULL;
 384        int rc;
 385
 386        BUG_ON(filp->private_data);
 387
 388        mutex_lock(&fsi->mutex);
 389
 390        rc = avc_has_perm(&selinux_state,
 391                          current_sid(), SECINITSID_SECURITY,
 392                          SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 393        if (rc)
 394                goto err;
 395
 396        rc = -EBUSY;
 397        if (fsi->policy_opened)
 398                goto err;
 399
 400        rc = -ENOMEM;
 401        plm = kzalloc(sizeof(*plm), GFP_KERNEL);
 402        if (!plm)
 403                goto err;
 404
 405        if (i_size_read(inode) != security_policydb_len(state)) {
 406                inode_lock(inode);
 407                i_size_write(inode, security_policydb_len(state));
 408                inode_unlock(inode);
 409        }
 410
 411        rc = security_read_policy(state, &plm->data, &plm->len);
 412        if (rc)
 413                goto err;
 414
 415        fsi->policy_opened = 1;
 416
 417        filp->private_data = plm;
 418
 419        mutex_unlock(&fsi->mutex);
 420
 421        return 0;
 422err:
 423        mutex_unlock(&fsi->mutex);
 424
 425        if (plm)
 426                vfree(plm->data);
 427        kfree(plm);
 428        return rc;
 429}
 430
 431static int sel_release_policy(struct inode *inode, struct file *filp)
 432{
 433        struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
 434        struct policy_load_memory *plm = filp->private_data;
 435
 436        BUG_ON(!plm);
 437
 438        fsi->policy_opened = 0;
 439
 440        vfree(plm->data);
 441        kfree(plm);
 442
 443        return 0;
 444}
 445
 446static ssize_t sel_read_policy(struct file *filp, char __user *buf,
 447                               size_t count, loff_t *ppos)
 448{
 449        struct policy_load_memory *plm = filp->private_data;
 450        int ret;
 451
 452        ret = avc_has_perm(&selinux_state,
 453                           current_sid(), SECINITSID_SECURITY,
 454                          SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 455        if (ret)
 456                return ret;
 457
 458        return simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
 459}
 460
 461static vm_fault_t sel_mmap_policy_fault(struct vm_fault *vmf)
 462{
 463        struct policy_load_memory *plm = vmf->vma->vm_file->private_data;
 464        unsigned long offset;
 465        struct page *page;
 466
 467        if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
 468                return VM_FAULT_SIGBUS;
 469
 470        offset = vmf->pgoff << PAGE_SHIFT;
 471        if (offset >= roundup(plm->len, PAGE_SIZE))
 472                return VM_FAULT_SIGBUS;
 473
 474        page = vmalloc_to_page(plm->data + offset);
 475        get_page(page);
 476
 477        vmf->page = page;
 478
 479        return 0;
 480}
 481
 482static const struct vm_operations_struct sel_mmap_policy_ops = {
 483        .fault = sel_mmap_policy_fault,
 484        .page_mkwrite = sel_mmap_policy_fault,
 485};
 486
 487static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
 488{
 489        if (vma->vm_flags & VM_SHARED) {
 490                /* do not allow mprotect to make mapping writable */
 491                vma->vm_flags &= ~VM_MAYWRITE;
 492
 493                if (vma->vm_flags & VM_WRITE)
 494                        return -EACCES;
 495        }
 496
 497        vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 498        vma->vm_ops = &sel_mmap_policy_ops;
 499
 500        return 0;
 501}
 502
 503static const struct file_operations sel_policy_ops = {
 504        .open           = sel_open_policy,
 505        .read           = sel_read_policy,
 506        .mmap           = sel_mmap_policy,
 507        .release        = sel_release_policy,
 508        .llseek         = generic_file_llseek,
 509};
 510
 511static int sel_make_policy_nodes(struct selinux_fs_info *fsi)
 512{
 513        int ret;
 514
 515        ret = sel_make_bools(fsi);
 516        if (ret) {
 517                pr_err("SELinux: failed to load policy booleans\n");
 518                return ret;
 519        }
 520
 521        ret = sel_make_classes(fsi);
 522        if (ret) {
 523                pr_err("SELinux: failed to load policy classes\n");
 524                return ret;
 525        }
 526
 527        ret = sel_make_policycap(fsi);
 528        if (ret) {
 529                pr_err("SELinux: failed to load policy capabilities\n");
 530                return ret;
 531        }
 532
 533        return 0;
 534}
 535
 536static ssize_t sel_write_load(struct file *file, const char __user *buf,
 537                              size_t count, loff_t *ppos)
 538
 539{
 540        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 541        ssize_t length;
 542        void *data = NULL;
 543
 544        mutex_lock(&fsi->mutex);
 545
 546        length = avc_has_perm(&selinux_state,
 547                              current_sid(), SECINITSID_SECURITY,
 548                              SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
 549        if (length)
 550                goto out;
 551
 552        /* No partial writes. */
 553        length = -EINVAL;
 554        if (*ppos != 0)
 555                goto out;
 556
 557        length = -ENOMEM;
 558        data = vmalloc(count);
 559        if (!data)
 560                goto out;
 561
 562        length = -EFAULT;
 563        if (copy_from_user(data, buf, count) != 0)
 564                goto out;
 565
 566        length = security_load_policy(fsi->state, data, count);
 567        if (length) {
 568                pr_warn_ratelimited("SELinux: failed to load policy\n");
 569                goto out;
 570        }
 571
 572        length = sel_make_policy_nodes(fsi);
 573        if (length)
 574                goto out1;
 575
 576        length = count;
 577
 578out1:
 579        audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
 580                "auid=%u ses=%u lsm=selinux res=1",
 581                from_kuid(&init_user_ns, audit_get_loginuid(current)),
 582                audit_get_sessionid(current));
 583out:
 584        mutex_unlock(&fsi->mutex);
 585        vfree(data);
 586        return length;
 587}
 588
 589static const struct file_operations sel_load_ops = {
 590        .write          = sel_write_load,
 591        .llseek         = generic_file_llseek,
 592};
 593
 594static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
 595{
 596        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 597        struct selinux_state *state = fsi->state;
 598        char *canon = NULL;
 599        u32 sid, len;
 600        ssize_t length;
 601
 602        length = avc_has_perm(&selinux_state,
 603                              current_sid(), SECINITSID_SECURITY,
 604                              SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
 605        if (length)
 606                goto out;
 607
 608        length = security_context_to_sid(state, buf, size, &sid, GFP_KERNEL);
 609        if (length)
 610                goto out;
 611
 612        length = security_sid_to_context(state, sid, &canon, &len);
 613        if (length)
 614                goto out;
 615
 616        length = -ERANGE;
 617        if (len > SIMPLE_TRANSACTION_LIMIT) {
 618                pr_err("SELinux: %s:  context size (%u) exceeds "
 619                        "payload max\n", __func__, len);
 620                goto out;
 621        }
 622
 623        memcpy(buf, canon, len);
 624        length = len;
 625out:
 626        kfree(canon);
 627        return length;
 628}
 629
 630static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
 631                                     size_t count, loff_t *ppos)
 632{
 633        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 634        char tmpbuf[TMPBUFLEN];
 635        ssize_t length;
 636
 637        length = scnprintf(tmpbuf, TMPBUFLEN, "%u", fsi->state->checkreqprot);
 638        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 639}
 640
 641static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
 642                                      size_t count, loff_t *ppos)
 643{
 644        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 645        char *page;
 646        ssize_t length;
 647        unsigned int new_value;
 648
 649        length = avc_has_perm(&selinux_state,
 650                              current_sid(), SECINITSID_SECURITY,
 651                              SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
 652                              NULL);
 653        if (length)
 654                return length;
 655
 656        if (count >= PAGE_SIZE)
 657                return -ENOMEM;
 658
 659        /* No partial writes. */
 660        if (*ppos != 0)
 661                return -EINVAL;
 662
 663        page = memdup_user_nul(buf, count);
 664        if (IS_ERR(page))
 665                return PTR_ERR(page);
 666
 667        length = -EINVAL;
 668        if (sscanf(page, "%u", &new_value) != 1)
 669                goto out;
 670
 671        if (new_value) {
 672                char comm[sizeof(current->comm)];
 673
 674                memcpy(comm, current->comm, sizeof(comm));
 675                pr_warn_once("SELinux: %s (%d) set checkreqprot to 1. This is deprecated and will be rejected in a future kernel release.\n",
 676                             comm, current->pid);
 677        }
 678
 679        fsi->state->checkreqprot = new_value ? 1 : 0;
 680        length = count;
 681out:
 682        kfree(page);
 683        return length;
 684}
 685static const struct file_operations sel_checkreqprot_ops = {
 686        .read           = sel_read_checkreqprot,
 687        .write          = sel_write_checkreqprot,
 688        .llseek         = generic_file_llseek,
 689};
 690
 691static ssize_t sel_write_validatetrans(struct file *file,
 692                                        const char __user *buf,
 693                                        size_t count, loff_t *ppos)
 694{
 695        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 696        struct selinux_state *state = fsi->state;
 697        char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
 698        char *req = NULL;
 699        u32 osid, nsid, tsid;
 700        u16 tclass;
 701        int rc;
 702
 703        rc = avc_has_perm(&selinux_state,
 704                          current_sid(), SECINITSID_SECURITY,
 705                          SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
 706        if (rc)
 707                goto out;
 708
 709        rc = -ENOMEM;
 710        if (count >= PAGE_SIZE)
 711                goto out;
 712
 713        /* No partial writes. */
 714        rc = -EINVAL;
 715        if (*ppos != 0)
 716                goto out;
 717
 718        req = memdup_user_nul(buf, count);
 719        if (IS_ERR(req)) {
 720                rc = PTR_ERR(req);
 721                req = NULL;
 722                goto out;
 723        }
 724
 725        rc = -ENOMEM;
 726        oldcon = kzalloc(count + 1, GFP_KERNEL);
 727        if (!oldcon)
 728                goto out;
 729
 730        newcon = kzalloc(count + 1, GFP_KERNEL);
 731        if (!newcon)
 732                goto out;
 733
 734        taskcon = kzalloc(count + 1, GFP_KERNEL);
 735        if (!taskcon)
 736                goto out;
 737
 738        rc = -EINVAL;
 739        if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
 740                goto out;
 741
 742        rc = security_context_str_to_sid(state, oldcon, &osid, GFP_KERNEL);
 743        if (rc)
 744                goto out;
 745
 746        rc = security_context_str_to_sid(state, newcon, &nsid, GFP_KERNEL);
 747        if (rc)
 748                goto out;
 749
 750        rc = security_context_str_to_sid(state, taskcon, &tsid, GFP_KERNEL);
 751        if (rc)
 752                goto out;
 753
 754        rc = security_validate_transition_user(state, osid, nsid, tsid, tclass);
 755        if (!rc)
 756                rc = count;
 757out:
 758        kfree(req);
 759        kfree(oldcon);
 760        kfree(newcon);
 761        kfree(taskcon);
 762        return rc;
 763}
 764
 765static const struct file_operations sel_transition_ops = {
 766        .write          = sel_write_validatetrans,
 767        .llseek         = generic_file_llseek,
 768};
 769
 770/*
 771 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 772 */
 773static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
 774static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
 775static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
 776static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
 777static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
 778
 779static ssize_t (*const write_op[])(struct file *, char *, size_t) = {
 780        [SEL_ACCESS] = sel_write_access,
 781        [SEL_CREATE] = sel_write_create,
 782        [SEL_RELABEL] = sel_write_relabel,
 783        [SEL_USER] = sel_write_user,
 784        [SEL_MEMBER] = sel_write_member,
 785        [SEL_CONTEXT] = sel_write_context,
 786};
 787
 788static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 789{
 790        ino_t ino = file_inode(file)->i_ino;
 791        char *data;
 792        ssize_t rv;
 793
 794        if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
 795                return -EINVAL;
 796
 797        data = simple_transaction_get(file, buf, size);
 798        if (IS_ERR(data))
 799                return PTR_ERR(data);
 800
 801        rv = write_op[ino](file, data, size);
 802        if (rv > 0) {
 803                simple_transaction_set(file, rv);
 804                rv = size;
 805        }
 806        return rv;
 807}
 808
 809static const struct file_operations transaction_ops = {
 810        .write          = selinux_transaction_write,
 811        .read           = simple_transaction_read,
 812        .release        = simple_transaction_release,
 813        .llseek         = generic_file_llseek,
 814};
 815
 816/*
 817 * payload - write methods
 818 * If the method has a response, the response should be put in buf,
 819 * and the length returned.  Otherwise return 0 or and -error.
 820 */
 821
 822static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
 823{
 824        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 825        struct selinux_state *state = fsi->state;
 826        char *scon = NULL, *tcon = NULL;
 827        u32 ssid, tsid;
 828        u16 tclass;
 829        struct av_decision avd;
 830        ssize_t length;
 831
 832        length = avc_has_perm(&selinux_state,
 833                              current_sid(), SECINITSID_SECURITY,
 834                              SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
 835        if (length)
 836                goto out;
 837
 838        length = -ENOMEM;
 839        scon = kzalloc(size + 1, GFP_KERNEL);
 840        if (!scon)
 841                goto out;
 842
 843        length = -ENOMEM;
 844        tcon = kzalloc(size + 1, GFP_KERNEL);
 845        if (!tcon)
 846                goto out;
 847
 848        length = -EINVAL;
 849        if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 850                goto out;
 851
 852        length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
 853        if (length)
 854                goto out;
 855
 856        length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
 857        if (length)
 858                goto out;
 859
 860        security_compute_av_user(state, ssid, tsid, tclass, &avd);
 861
 862        length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 863                          "%x %x %x %x %u %x",
 864                          avd.allowed, 0xffffffff,
 865                          avd.auditallow, avd.auditdeny,
 866                          avd.seqno, avd.flags);
 867out:
 868        kfree(tcon);
 869        kfree(scon);
 870        return length;
 871}
 872
 873static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
 874{
 875        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 876        struct selinux_state *state = fsi->state;
 877        char *scon = NULL, *tcon = NULL;
 878        char *namebuf = NULL, *objname = NULL;
 879        u32 ssid, tsid, newsid;
 880        u16 tclass;
 881        ssize_t length;
 882        char *newcon = NULL;
 883        u32 len;
 884        int nargs;
 885
 886        length = avc_has_perm(&selinux_state,
 887                              current_sid(), SECINITSID_SECURITY,
 888                              SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
 889                              NULL);
 890        if (length)
 891                goto out;
 892
 893        length = -ENOMEM;
 894        scon = kzalloc(size + 1, GFP_KERNEL);
 895        if (!scon)
 896                goto out;
 897
 898        length = -ENOMEM;
 899        tcon = kzalloc(size + 1, GFP_KERNEL);
 900        if (!tcon)
 901                goto out;
 902
 903        length = -ENOMEM;
 904        namebuf = kzalloc(size + 1, GFP_KERNEL);
 905        if (!namebuf)
 906                goto out;
 907
 908        length = -EINVAL;
 909        nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
 910        if (nargs < 3 || nargs > 4)
 911                goto out;
 912        if (nargs == 4) {
 913                /*
 914                 * If and when the name of new object to be queried contains
 915                 * either whitespace or multibyte characters, they shall be
 916                 * encoded based on the percentage-encoding rule.
 917                 * If not encoded, the sscanf logic picks up only left-half
 918                 * of the supplied name; splitted by a whitespace unexpectedly.
 919                 */
 920                char   *r, *w;
 921                int     c1, c2;
 922
 923                r = w = namebuf;
 924                do {
 925                        c1 = *r++;
 926                        if (c1 == '+')
 927                                c1 = ' ';
 928                        else if (c1 == '%') {
 929                                c1 = hex_to_bin(*r++);
 930                                if (c1 < 0)
 931                                        goto out;
 932                                c2 = hex_to_bin(*r++);
 933                                if (c2 < 0)
 934                                        goto out;
 935                                c1 = (c1 << 4) | c2;
 936                        }
 937                        *w++ = c1;
 938                } while (c1 != '\0');
 939
 940                objname = namebuf;
 941        }
 942
 943        length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
 944        if (length)
 945                goto out;
 946
 947        length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
 948        if (length)
 949                goto out;
 950
 951        length = security_transition_sid_user(state, ssid, tsid, tclass,
 952                                              objname, &newsid);
 953        if (length)
 954                goto out;
 955
 956        length = security_sid_to_context(state, newsid, &newcon, &len);
 957        if (length)
 958                goto out;
 959
 960        length = -ERANGE;
 961        if (len > SIMPLE_TRANSACTION_LIMIT) {
 962                pr_err("SELinux: %s:  context size (%u) exceeds "
 963                        "payload max\n", __func__, len);
 964                goto out;
 965        }
 966
 967        memcpy(buf, newcon, len);
 968        length = len;
 969out:
 970        kfree(newcon);
 971        kfree(namebuf);
 972        kfree(tcon);
 973        kfree(scon);
 974        return length;
 975}
 976
 977static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
 978{
 979        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 980        struct selinux_state *state = fsi->state;
 981        char *scon = NULL, *tcon = NULL;
 982        u32 ssid, tsid, newsid;
 983        u16 tclass;
 984        ssize_t length;
 985        char *newcon = NULL;
 986        u32 len;
 987
 988        length = avc_has_perm(&selinux_state,
 989                              current_sid(), SECINITSID_SECURITY,
 990                              SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
 991                              NULL);
 992        if (length)
 993                goto out;
 994
 995        length = -ENOMEM;
 996        scon = kzalloc(size + 1, GFP_KERNEL);
 997        if (!scon)
 998                goto out;
 999
1000        length = -ENOMEM;
1001        tcon = kzalloc(size + 1, GFP_KERNEL);
1002        if (!tcon)
1003                goto out;
1004
1005        length = -EINVAL;
1006        if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1007                goto out;
1008
1009        length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
1010        if (length)
1011                goto out;
1012
1013        length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1014        if (length)
1015                goto out;
1016
1017        length = security_change_sid(state, ssid, tsid, tclass, &newsid);
1018        if (length)
1019                goto out;
1020
1021        length = security_sid_to_context(state, newsid, &newcon, &len);
1022        if (length)
1023                goto out;
1024
1025        length = -ERANGE;
1026        if (len > SIMPLE_TRANSACTION_LIMIT)
1027                goto out;
1028
1029        memcpy(buf, newcon, len);
1030        length = len;
1031out:
1032        kfree(newcon);
1033        kfree(tcon);
1034        kfree(scon);
1035        return length;
1036}
1037
1038static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
1039{
1040        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1041        struct selinux_state *state = fsi->state;
1042        char *con = NULL, *user = NULL, *ptr;
1043        u32 sid, *sids = NULL;
1044        ssize_t length;
1045        char *newcon;
1046        int i, rc;
1047        u32 len, nsids;
1048
1049        length = avc_has_perm(&selinux_state,
1050                              current_sid(), SECINITSID_SECURITY,
1051                              SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
1052                              NULL);
1053        if (length)
1054                goto out;
1055
1056        length = -ENOMEM;
1057        con = kzalloc(size + 1, GFP_KERNEL);
1058        if (!con)
1059                goto out;
1060
1061        length = -ENOMEM;
1062        user = kzalloc(size + 1, GFP_KERNEL);
1063        if (!user)
1064                goto out;
1065
1066        length = -EINVAL;
1067        if (sscanf(buf, "%s %s", con, user) != 2)
1068                goto out;
1069
1070        length = security_context_str_to_sid(state, con, &sid, GFP_KERNEL);
1071        if (length)
1072                goto out;
1073
1074        length = security_get_user_sids(state, sid, user, &sids, &nsids);
1075        if (length)
1076                goto out;
1077
1078        length = sprintf(buf, "%u", nsids) + 1;
1079        ptr = buf + length;
1080        for (i = 0; i < nsids; i++) {
1081                rc = security_sid_to_context(state, sids[i], &newcon, &len);
1082                if (rc) {
1083                        length = rc;
1084                        goto out;
1085                }
1086                if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1087                        kfree(newcon);
1088                        length = -ERANGE;
1089                        goto out;
1090                }
1091                memcpy(ptr, newcon, len);
1092                kfree(newcon);
1093                ptr += len;
1094                length += len;
1095        }
1096out:
1097        kfree(sids);
1098        kfree(user);
1099        kfree(con);
1100        return length;
1101}
1102
1103static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1104{
1105        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1106        struct selinux_state *state = fsi->state;
1107        char *scon = NULL, *tcon = NULL;
1108        u32 ssid, tsid, newsid;
1109        u16 tclass;
1110        ssize_t length;
1111        char *newcon = NULL;
1112        u32 len;
1113
1114        length = avc_has_perm(&selinux_state,
1115                              current_sid(), SECINITSID_SECURITY,
1116                              SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
1117                              NULL);
1118        if (length)
1119                goto out;
1120
1121        length = -ENOMEM;
1122        scon = kzalloc(size + 1, GFP_KERNEL);
1123        if (!scon)
1124                goto out;
1125
1126        length = -ENOMEM;
1127        tcon = kzalloc(size + 1, GFP_KERNEL);
1128        if (!tcon)
1129                goto out;
1130
1131        length = -EINVAL;
1132        if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1133                goto out;
1134
1135        length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
1136        if (length)
1137                goto out;
1138
1139        length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1140        if (length)
1141                goto out;
1142
1143        length = security_member_sid(state, ssid, tsid, tclass, &newsid);
1144        if (length)
1145                goto out;
1146
1147        length = security_sid_to_context(state, newsid, &newcon, &len);
1148        if (length)
1149                goto out;
1150
1151        length = -ERANGE;
1152        if (len > SIMPLE_TRANSACTION_LIMIT) {
1153                pr_err("SELinux: %s:  context size (%u) exceeds "
1154                        "payload max\n", __func__, len);
1155                goto out;
1156        }
1157
1158        memcpy(buf, newcon, len);
1159        length = len;
1160out:
1161        kfree(newcon);
1162        kfree(tcon);
1163        kfree(scon);
1164        return length;
1165}
1166
1167static struct inode *sel_make_inode(struct super_block *sb, int mode)
1168{
1169        struct inode *ret = new_inode(sb);
1170
1171        if (ret) {
1172                ret->i_mode = mode;
1173                ret->i_atime = ret->i_mtime = ret->i_ctime = current_time(ret);
1174        }
1175        return ret;
1176}
1177
1178static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1179                             size_t count, loff_t *ppos)
1180{
1181        struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1182        char *page = NULL;
1183        ssize_t length;
1184        ssize_t ret;
1185        int cur_enforcing;
1186        unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1187        const char *name = filep->f_path.dentry->d_name.name;
1188
1189        mutex_lock(&fsi->mutex);
1190
1191        ret = -EINVAL;
1192        if (index >= fsi->bool_num || strcmp(name,
1193                                             fsi->bool_pending_names[index]))
1194                goto out_unlock;
1195
1196        ret = -ENOMEM;
1197        page = (char *)get_zeroed_page(GFP_KERNEL);
1198        if (!page)
1199                goto out_unlock;
1200
1201        cur_enforcing = security_get_bool_value(fsi->state, index);
1202        if (cur_enforcing < 0) {
1203                ret = cur_enforcing;
1204                goto out_unlock;
1205        }
1206        length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1207                          fsi->bool_pending_values[index]);
1208        mutex_unlock(&fsi->mutex);
1209        ret = simple_read_from_buffer(buf, count, ppos, page, length);
1210out_free:
1211        free_page((unsigned long)page);
1212        return ret;
1213
1214out_unlock:
1215        mutex_unlock(&fsi->mutex);
1216        goto out_free;
1217}
1218
1219static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1220                              size_t count, loff_t *ppos)
1221{
1222        struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1223        char *page = NULL;
1224        ssize_t length;
1225        int new_value;
1226        unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1227        const char *name = filep->f_path.dentry->d_name.name;
1228
1229        if (count >= PAGE_SIZE)
1230                return -ENOMEM;
1231
1232        /* No partial writes. */
1233        if (*ppos != 0)
1234                return -EINVAL;
1235
1236        page = memdup_user_nul(buf, count);
1237        if (IS_ERR(page))
1238                return PTR_ERR(page);
1239
1240        mutex_lock(&fsi->mutex);
1241
1242        length = avc_has_perm(&selinux_state,
1243                              current_sid(), SECINITSID_SECURITY,
1244                              SECCLASS_SECURITY, SECURITY__SETBOOL,
1245                              NULL);
1246        if (length)
1247                goto out;
1248
1249        length = -EINVAL;
1250        if (index >= fsi->bool_num || strcmp(name,
1251                                             fsi->bool_pending_names[index]))
1252                goto out;
1253
1254        length = -EINVAL;
1255        if (sscanf(page, "%d", &new_value) != 1)
1256                goto out;
1257
1258        if (new_value)
1259                new_value = 1;
1260
1261        fsi->bool_pending_values[index] = new_value;
1262        length = count;
1263
1264out:
1265        mutex_unlock(&fsi->mutex);
1266        kfree(page);
1267        return length;
1268}
1269
1270static const struct file_operations sel_bool_ops = {
1271        .read           = sel_read_bool,
1272        .write          = sel_write_bool,
1273        .llseek         = generic_file_llseek,
1274};
1275
1276static ssize_t sel_commit_bools_write(struct file *filep,
1277                                      const char __user *buf,
1278                                      size_t count, loff_t *ppos)
1279{
1280        struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1281        char *page = NULL;
1282        ssize_t length;
1283        int new_value;
1284
1285        if (count >= PAGE_SIZE)
1286                return -ENOMEM;
1287
1288        /* No partial writes. */
1289        if (*ppos != 0)
1290                return -EINVAL;
1291
1292        page = memdup_user_nul(buf, count);
1293        if (IS_ERR(page))
1294                return PTR_ERR(page);
1295
1296        mutex_lock(&fsi->mutex);
1297
1298        length = avc_has_perm(&selinux_state,
1299                              current_sid(), SECINITSID_SECURITY,
1300                              SECCLASS_SECURITY, SECURITY__SETBOOL,
1301                              NULL);
1302        if (length)
1303                goto out;
1304
1305        length = -EINVAL;
1306        if (sscanf(page, "%d", &new_value) != 1)
1307                goto out;
1308
1309        length = 0;
1310        if (new_value && fsi->bool_pending_values)
1311                length = security_set_bools(fsi->state, fsi->bool_num,
1312                                            fsi->bool_pending_values);
1313
1314        if (!length)
1315                length = count;
1316
1317out:
1318        mutex_unlock(&fsi->mutex);
1319        kfree(page);
1320        return length;
1321}
1322
1323static const struct file_operations sel_commit_bools_ops = {
1324        .write          = sel_commit_bools_write,
1325        .llseek         = generic_file_llseek,
1326};
1327
1328static void sel_remove_entries(struct dentry *de)
1329{
1330        d_genocide(de);
1331        shrink_dcache_parent(de);
1332}
1333
1334#define BOOL_DIR_NAME "booleans"
1335
1336static int sel_make_bools(struct selinux_fs_info *fsi)
1337{
1338        int ret;
1339        ssize_t len;
1340        struct dentry *dentry = NULL;
1341        struct dentry *dir = fsi->bool_dir;
1342        struct inode *inode = NULL;
1343        struct inode_security_struct *isec;
1344        char **names = NULL, *page;
1345        u32 i, num;
1346        int *values = NULL;
1347        u32 sid;
1348
1349        /* remove any existing files */
1350        for (i = 0; i < fsi->bool_num; i++)
1351                kfree(fsi->bool_pending_names[i]);
1352        kfree(fsi->bool_pending_names);
1353        kfree(fsi->bool_pending_values);
1354        fsi->bool_num = 0;
1355        fsi->bool_pending_names = NULL;
1356        fsi->bool_pending_values = NULL;
1357
1358        sel_remove_entries(dir);
1359
1360        ret = -ENOMEM;
1361        page = (char *)get_zeroed_page(GFP_KERNEL);
1362        if (!page)
1363                goto out;
1364
1365        ret = security_get_bools(fsi->state, &num, &names, &values);
1366        if (ret)
1367                goto out;
1368
1369        for (i = 0; i < num; i++) {
1370                ret = -ENOMEM;
1371                dentry = d_alloc_name(dir, names[i]);
1372                if (!dentry)
1373                        goto out;
1374
1375                ret = -ENOMEM;
1376                inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1377                if (!inode) {
1378                        dput(dentry);
1379                        goto out;
1380                }
1381
1382                ret = -ENAMETOOLONG;
1383                len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1384                if (len >= PAGE_SIZE) {
1385                        dput(dentry);
1386                        iput(inode);
1387                        goto out;
1388                }
1389
1390                isec = selinux_inode(inode);
1391                ret = security_genfs_sid(fsi->state, "selinuxfs", page,
1392                                         SECCLASS_FILE, &sid);
1393                if (ret) {
1394                        pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
1395                                           page);
1396                        sid = SECINITSID_SECURITY;
1397                }
1398
1399                isec->sid = sid;
1400                isec->initialized = LABEL_INITIALIZED;
1401                inode->i_fop = &sel_bool_ops;
1402                inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1403                d_add(dentry, inode);
1404        }
1405        fsi->bool_num = num;
1406        fsi->bool_pending_names = names;
1407        fsi->bool_pending_values = values;
1408
1409        free_page((unsigned long)page);
1410        return 0;
1411out:
1412        free_page((unsigned long)page);
1413
1414        if (names) {
1415                for (i = 0; i < num; i++)
1416                        kfree(names[i]);
1417                kfree(names);
1418        }
1419        kfree(values);
1420        sel_remove_entries(dir);
1421
1422        return ret;
1423}
1424
1425static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1426                                            size_t count, loff_t *ppos)
1427{
1428        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1429        struct selinux_state *state = fsi->state;
1430        char tmpbuf[TMPBUFLEN];
1431        ssize_t length;
1432
1433        length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1434                           avc_get_cache_threshold(state->avc));
1435        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1436}
1437
1438static ssize_t sel_write_avc_cache_threshold(struct file *file,
1439                                             const char __user *buf,
1440                                             size_t count, loff_t *ppos)
1441
1442{
1443        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1444        struct selinux_state *state = fsi->state;
1445        char *page;
1446        ssize_t ret;
1447        unsigned int new_value;
1448
1449        ret = avc_has_perm(&selinux_state,
1450                           current_sid(), SECINITSID_SECURITY,
1451                           SECCLASS_SECURITY, SECURITY__SETSECPARAM,
1452                           NULL);
1453        if (ret)
1454                return ret;
1455
1456        if (count >= PAGE_SIZE)
1457                return -ENOMEM;
1458
1459        /* No partial writes. */
1460        if (*ppos != 0)
1461                return -EINVAL;
1462
1463        page = memdup_user_nul(buf, count);
1464        if (IS_ERR(page))
1465                return PTR_ERR(page);
1466
1467        ret = -EINVAL;
1468        if (sscanf(page, "%u", &new_value) != 1)
1469                goto out;
1470
1471        avc_set_cache_threshold(state->avc, new_value);
1472
1473        ret = count;
1474out:
1475        kfree(page);
1476        return ret;
1477}
1478
1479static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1480                                       size_t count, loff_t *ppos)
1481{
1482        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1483        struct selinux_state *state = fsi->state;
1484        char *page;
1485        ssize_t length;
1486
1487        page = (char *)__get_free_page(GFP_KERNEL);
1488        if (!page)
1489                return -ENOMEM;
1490
1491        length = avc_get_hash_stats(state->avc, page);
1492        if (length >= 0)
1493                length = simple_read_from_buffer(buf, count, ppos, page, length);
1494        free_page((unsigned long)page);
1495
1496        return length;
1497}
1498
1499static ssize_t sel_read_sidtab_hash_stats(struct file *filp, char __user *buf,
1500                                        size_t count, loff_t *ppos)
1501{
1502        struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1503        struct selinux_state *state = fsi->state;
1504        char *page;
1505        ssize_t length;
1506
1507        page = (char *)__get_free_page(GFP_KERNEL);
1508        if (!page)
1509                return -ENOMEM;
1510
1511        length = security_sidtab_hash_stats(state, page);
1512        if (length >= 0)
1513                length = simple_read_from_buffer(buf, count, ppos, page,
1514                                                length);
1515        free_page((unsigned long)page);
1516
1517        return length;
1518}
1519
1520static const struct file_operations sel_sidtab_hash_stats_ops = {
1521        .read           = sel_read_sidtab_hash_stats,
1522        .llseek         = generic_file_llseek,
1523};
1524
1525static const struct file_operations sel_avc_cache_threshold_ops = {
1526        .read           = sel_read_avc_cache_threshold,
1527        .write          = sel_write_avc_cache_threshold,
1528        .llseek         = generic_file_llseek,
1529};
1530
1531static const struct file_operations sel_avc_hash_stats_ops = {
1532        .read           = sel_read_avc_hash_stats,
1533        .llseek         = generic_file_llseek,
1534};
1535
1536#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1537static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1538{
1539        int cpu;
1540
1541        for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1542                if (!cpu_possible(cpu))
1543                        continue;
1544                *idx = cpu + 1;
1545                return &per_cpu(avc_cache_stats, cpu);
1546        }
1547        (*idx)++;
1548        return NULL;
1549}
1550
1551static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1552{
1553        loff_t n = *pos - 1;
1554
1555        if (*pos == 0)
1556                return SEQ_START_TOKEN;
1557
1558        return sel_avc_get_stat_idx(&n);
1559}
1560
1561static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1562{
1563        return sel_avc_get_stat_idx(pos);
1564}
1565
1566static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1567{
1568        struct avc_cache_stats *st = v;
1569
1570        if (v == SEQ_START_TOKEN) {
1571                seq_puts(seq,
1572                         "lookups hits misses allocations reclaims frees\n");
1573        } else {
1574                unsigned int lookups = st->lookups;
1575                unsigned int misses = st->misses;
1576                unsigned int hits = lookups - misses;
1577                seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1578                           hits, misses, st->allocations,
1579                           st->reclaims, st->frees);
1580        }
1581        return 0;
1582}
1583
1584static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1585{ }
1586
1587static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1588        .start          = sel_avc_stats_seq_start,
1589        .next           = sel_avc_stats_seq_next,
1590        .show           = sel_avc_stats_seq_show,
1591        .stop           = sel_avc_stats_seq_stop,
1592};
1593
1594static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1595{
1596        return seq_open(file, &sel_avc_cache_stats_seq_ops);
1597}
1598
1599static const struct file_operations sel_avc_cache_stats_ops = {
1600        .open           = sel_open_avc_cache_stats,
1601        .read           = seq_read,
1602        .llseek         = seq_lseek,
1603        .release        = seq_release,
1604};
1605#endif
1606
1607static int sel_make_avc_files(struct dentry *dir)
1608{
1609        struct super_block *sb = dir->d_sb;
1610        struct selinux_fs_info *fsi = sb->s_fs_info;
1611        int i;
1612        static const struct tree_descr files[] = {
1613                { "cache_threshold",
1614                  &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1615                { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1616#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1617                { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1618#endif
1619        };
1620
1621        for (i = 0; i < ARRAY_SIZE(files); i++) {
1622                struct inode *inode;
1623                struct dentry *dentry;
1624
1625                dentry = d_alloc_name(dir, files[i].name);
1626                if (!dentry)
1627                        return -ENOMEM;
1628
1629                inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1630                if (!inode) {
1631                        dput(dentry);
1632                        return -ENOMEM;
1633                }
1634
1635                inode->i_fop = files[i].ops;
1636                inode->i_ino = ++fsi->last_ino;
1637                d_add(dentry, inode);
1638        }
1639
1640        return 0;
1641}
1642
1643static int sel_make_ss_files(struct dentry *dir)
1644{
1645        struct super_block *sb = dir->d_sb;
1646        struct selinux_fs_info *fsi = sb->s_fs_info;
1647        int i;
1648        static struct tree_descr files[] = {
1649                { "sidtab_hash_stats", &sel_sidtab_hash_stats_ops, S_IRUGO },
1650        };
1651
1652        for (i = 0; i < ARRAY_SIZE(files); i++) {
1653                struct inode *inode;
1654                struct dentry *dentry;
1655
1656                dentry = d_alloc_name(dir, files[i].name);
1657                if (!dentry)
1658                        return -ENOMEM;
1659
1660                inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1661                if (!inode) {
1662                        dput(dentry);
1663                        return -ENOMEM;
1664                }
1665
1666                inode->i_fop = files[i].ops;
1667                inode->i_ino = ++fsi->last_ino;
1668                d_add(dentry, inode);
1669        }
1670
1671        return 0;
1672}
1673
1674static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1675                                size_t count, loff_t *ppos)
1676{
1677        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1678        char *con;
1679        u32 sid, len;
1680        ssize_t ret;
1681
1682        sid = file_inode(file)->i_ino&SEL_INO_MASK;
1683        ret = security_sid_to_context(fsi->state, sid, &con, &len);
1684        if (ret)
1685                return ret;
1686
1687        ret = simple_read_from_buffer(buf, count, ppos, con, len);
1688        kfree(con);
1689        return ret;
1690}
1691
1692static const struct file_operations sel_initcon_ops = {
1693        .read           = sel_read_initcon,
1694        .llseek         = generic_file_llseek,
1695};
1696
1697static int sel_make_initcon_files(struct dentry *dir)
1698{
1699        int i;
1700
1701        for (i = 1; i <= SECINITSID_NUM; i++) {
1702                struct inode *inode;
1703                struct dentry *dentry;
1704                const char *s = security_get_initial_sid_context(i);
1705
1706                if (!s)
1707                        continue;
1708                dentry = d_alloc_name(dir, s);
1709                if (!dentry)
1710                        return -ENOMEM;
1711
1712                inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1713                if (!inode) {
1714                        dput(dentry);
1715                        return -ENOMEM;
1716                }
1717
1718                inode->i_fop = &sel_initcon_ops;
1719                inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1720                d_add(dentry, inode);
1721        }
1722
1723        return 0;
1724}
1725
1726static inline unsigned long sel_class_to_ino(u16 class)
1727{
1728        return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1729}
1730
1731static inline u16 sel_ino_to_class(unsigned long ino)
1732{
1733        return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1734}
1735
1736static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1737{
1738        return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1739}
1740
1741static inline u32 sel_ino_to_perm(unsigned long ino)
1742{
1743        return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1744}
1745
1746static ssize_t sel_read_class(struct file *file, char __user *buf,
1747                                size_t count, loff_t *ppos)
1748{
1749        unsigned long ino = file_inode(file)->i_ino;
1750        char res[TMPBUFLEN];
1751        ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1752        return simple_read_from_buffer(buf, count, ppos, res, len);
1753}
1754
1755static const struct file_operations sel_class_ops = {
1756        .read           = sel_read_class,
1757        .llseek         = generic_file_llseek,
1758};
1759
1760static ssize_t sel_read_perm(struct file *file, char __user *buf,
1761                                size_t count, loff_t *ppos)
1762{
1763        unsigned long ino = file_inode(file)->i_ino;
1764        char res[TMPBUFLEN];
1765        ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1766        return simple_read_from_buffer(buf, count, ppos, res, len);
1767}
1768
1769static const struct file_operations sel_perm_ops = {
1770        .read           = sel_read_perm,
1771        .llseek         = generic_file_llseek,
1772};
1773
1774static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1775                                  size_t count, loff_t *ppos)
1776{
1777        struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1778        int value;
1779        char tmpbuf[TMPBUFLEN];
1780        ssize_t length;
1781        unsigned long i_ino = file_inode(file)->i_ino;
1782
1783        value = security_policycap_supported(fsi->state, i_ino & SEL_INO_MASK);
1784        length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1785
1786        return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1787}
1788
1789static const struct file_operations sel_policycap_ops = {
1790        .read           = sel_read_policycap,
1791        .llseek         = generic_file_llseek,
1792};
1793
1794static int sel_make_perm_files(char *objclass, int classvalue,
1795                                struct dentry *dir)
1796{
1797        struct selinux_fs_info *fsi = dir->d_sb->s_fs_info;
1798        int i, rc, nperms;
1799        char **perms;
1800
1801        rc = security_get_permissions(fsi->state, objclass, &perms, &nperms);
1802        if (rc)
1803                return rc;
1804
1805        for (i = 0; i < nperms; i++) {
1806                struct inode *inode;
1807                struct dentry *dentry;
1808
1809                rc = -ENOMEM;
1810                dentry = d_alloc_name(dir, perms[i]);
1811                if (!dentry)
1812                        goto out;
1813
1814                rc = -ENOMEM;
1815                inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1816                if (!inode) {
1817                        dput(dentry);
1818                        goto out;
1819                }
1820
1821                inode->i_fop = &sel_perm_ops;
1822                /* i+1 since perm values are 1-indexed */
1823                inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1824                d_add(dentry, inode);
1825        }
1826        rc = 0;
1827out:
1828        for (i = 0; i < nperms; i++)
1829                kfree(perms[i]);
1830        kfree(perms);
1831        return rc;
1832}
1833
1834static int sel_make_class_dir_entries(char *classname, int index,
1835                                        struct dentry *dir)
1836{
1837        struct super_block *sb = dir->d_sb;
1838        struct selinux_fs_info *fsi = sb->s_fs_info;
1839        struct dentry *dentry = NULL;
1840        struct inode *inode = NULL;
1841        int rc;
1842
1843        dentry = d_alloc_name(dir, "index");
1844        if (!dentry)
1845                return -ENOMEM;
1846
1847        inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1848        if (!inode) {
1849                dput(dentry);
1850                return -ENOMEM;
1851        }
1852
1853        inode->i_fop = &sel_class_ops;
1854        inode->i_ino = sel_class_to_ino(index);
1855        d_add(dentry, inode);
1856
1857        dentry = sel_make_dir(dir, "perms", &fsi->last_class_ino);
1858        if (IS_ERR(dentry))
1859                return PTR_ERR(dentry);
1860
1861        rc = sel_make_perm_files(classname, index, dentry);
1862
1863        return rc;
1864}
1865
1866static int sel_make_classes(struct selinux_fs_info *fsi)
1867{
1868
1869        int rc, nclasses, i;
1870        char **classes;
1871
1872        /* delete any existing entries */
1873        sel_remove_entries(fsi->class_dir);
1874
1875        rc = security_get_classes(fsi->state, &classes, &nclasses);
1876        if (rc)
1877                return rc;
1878
1879        /* +2 since classes are 1-indexed */
1880        fsi->last_class_ino = sel_class_to_ino(nclasses + 2);
1881
1882        for (i = 0; i < nclasses; i++) {
1883                struct dentry *class_name_dir;
1884
1885                class_name_dir = sel_make_dir(fsi->class_dir, classes[i],
1886                                              &fsi->last_class_ino);
1887                if (IS_ERR(class_name_dir)) {
1888                        rc = PTR_ERR(class_name_dir);
1889                        goto out;
1890                }
1891
1892                /* i+1 since class values are 1-indexed */
1893                rc = sel_make_class_dir_entries(classes[i], i + 1,
1894                                class_name_dir);
1895                if (rc)
1896                        goto out;
1897        }
1898        rc = 0;
1899out:
1900        for (i = 0; i < nclasses; i++)
1901                kfree(classes[i]);
1902        kfree(classes);
1903        return rc;
1904}
1905
1906static int sel_make_policycap(struct selinux_fs_info *fsi)
1907{
1908        unsigned int iter;
1909        struct dentry *dentry = NULL;
1910        struct inode *inode = NULL;
1911
1912        sel_remove_entries(fsi->policycap_dir);
1913
1914        for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1915                if (iter < ARRAY_SIZE(selinux_policycap_names))
1916                        dentry = d_alloc_name(fsi->policycap_dir,
1917                                              selinux_policycap_names[iter]);
1918                else
1919                        dentry = d_alloc_name(fsi->policycap_dir, "unknown");
1920
1921                if (dentry == NULL)
1922                        return -ENOMEM;
1923
1924                inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
1925                if (inode == NULL) {
1926                        dput(dentry);
1927                        return -ENOMEM;
1928                }
1929
1930                inode->i_fop = &sel_policycap_ops;
1931                inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1932                d_add(dentry, inode);
1933        }
1934
1935        return 0;
1936}
1937
1938static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1939                        unsigned long *ino)
1940{
1941        struct dentry *dentry = d_alloc_name(dir, name);
1942        struct inode *inode;
1943
1944        if (!dentry)
1945                return ERR_PTR(-ENOMEM);
1946
1947        inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1948        if (!inode) {
1949                dput(dentry);
1950                return ERR_PTR(-ENOMEM);
1951        }
1952
1953        inode->i_op = &simple_dir_inode_operations;
1954        inode->i_fop = &simple_dir_operations;
1955        inode->i_ino = ++(*ino);
1956        /* directory inodes start off with i_nlink == 2 (for "." entry) */
1957        inc_nlink(inode);
1958        d_add(dentry, inode);
1959        /* bump link count on parent directory, too */
1960        inc_nlink(d_inode(dir));
1961
1962        return dentry;
1963}
1964
1965#define NULL_FILE_NAME "null"
1966
1967static int sel_fill_super(struct super_block *sb, struct fs_context *fc)
1968{
1969        struct selinux_fs_info *fsi;
1970        int ret;
1971        struct dentry *dentry;
1972        struct inode *inode;
1973        struct inode_security_struct *isec;
1974
1975        static const struct tree_descr selinux_files[] = {
1976                [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1977                [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1978                [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1979                [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1980                [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1981                [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1982                [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1983                [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1984                [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1985                [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1986                [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1987                [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1988                [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1989                [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1990                [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1991                [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1992                [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
1993                [SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
1994                                        S_IWUGO},
1995                /* last one */ {""}
1996        };
1997
1998        ret = selinux_fs_info_create(sb);
1999        if (ret)
2000                goto err;
2001
2002        ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
2003        if (ret)
2004                goto err;
2005
2006        fsi = sb->s_fs_info;
2007        fsi->bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &fsi->last_ino);
2008        if (IS_ERR(fsi->bool_dir)) {
2009                ret = PTR_ERR(fsi->bool_dir);
2010                fsi->bool_dir = NULL;
2011                goto err;
2012        }
2013
2014        ret = -ENOMEM;
2015        dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
2016        if (!dentry)
2017                goto err;
2018
2019        ret = -ENOMEM;
2020        inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
2021        if (!inode) {
2022                dput(dentry);
2023                goto err;
2024        }
2025
2026        inode->i_ino = ++fsi->last_ino;
2027        isec = selinux_inode(inode);
2028        isec->sid = SECINITSID_DEVNULL;
2029        isec->sclass = SECCLASS_CHR_FILE;
2030        isec->initialized = LABEL_INITIALIZED;
2031
2032        init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
2033        d_add(dentry, inode);
2034
2035        dentry = sel_make_dir(sb->s_root, "avc", &fsi->last_ino);
2036        if (IS_ERR(dentry)) {
2037                ret = PTR_ERR(dentry);
2038                goto err;
2039        }
2040
2041        ret = sel_make_avc_files(dentry);
2042
2043        dentry = sel_make_dir(sb->s_root, "ss", &fsi->last_ino);
2044        if (IS_ERR(dentry)) {
2045                ret = PTR_ERR(dentry);
2046                goto err;
2047        }
2048
2049        ret = sel_make_ss_files(dentry);
2050        if (ret)
2051                goto err;
2052
2053        dentry = sel_make_dir(sb->s_root, "initial_contexts", &fsi->last_ino);
2054        if (IS_ERR(dentry)) {
2055                ret = PTR_ERR(dentry);
2056                goto err;
2057        }
2058
2059        ret = sel_make_initcon_files(dentry);
2060        if (ret)
2061                goto err;
2062
2063        fsi->class_dir = sel_make_dir(sb->s_root, "class", &fsi->last_ino);
2064        if (IS_ERR(fsi->class_dir)) {
2065                ret = PTR_ERR(fsi->class_dir);
2066                fsi->class_dir = NULL;
2067                goto err;
2068        }
2069
2070        fsi->policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities",
2071                                          &fsi->last_ino);
2072        if (IS_ERR(fsi->policycap_dir)) {
2073                ret = PTR_ERR(fsi->policycap_dir);
2074                fsi->policycap_dir = NULL;
2075                goto err;
2076        }
2077
2078        ret = sel_make_policy_nodes(fsi);
2079        if (ret)
2080                goto err;
2081        return 0;
2082err:
2083        pr_err("SELinux: %s:  failed while creating inodes\n",
2084                __func__);
2085
2086        selinux_fs_info_free(sb);
2087
2088        return ret;
2089}
2090
2091static int sel_get_tree(struct fs_context *fc)
2092{
2093        return get_tree_single(fc, sel_fill_super);
2094}
2095
2096static const struct fs_context_operations sel_context_ops = {
2097        .get_tree       = sel_get_tree,
2098};
2099
2100static int sel_init_fs_context(struct fs_context *fc)
2101{
2102        fc->ops = &sel_context_ops;
2103        return 0;
2104}
2105
2106static void sel_kill_sb(struct super_block *sb)
2107{
2108        selinux_fs_info_free(sb);
2109        kill_litter_super(sb);
2110}
2111
2112static struct file_system_type sel_fs_type = {
2113        .name           = "selinuxfs",
2114        .init_fs_context = sel_init_fs_context,
2115        .kill_sb        = sel_kill_sb,
2116};
2117
2118struct vfsmount *selinuxfs_mount;
2119struct path selinux_null;
2120
2121static int __init init_sel_fs(void)
2122{
2123        struct qstr null_name = QSTR_INIT(NULL_FILE_NAME,
2124                                          sizeof(NULL_FILE_NAME)-1);
2125        int err;
2126
2127        if (!selinux_enabled_boot)
2128                return 0;
2129
2130        err = sysfs_create_mount_point(fs_kobj, "selinux");
2131        if (err)
2132                return err;
2133
2134        err = register_filesystem(&sel_fs_type);
2135        if (err) {
2136                sysfs_remove_mount_point(fs_kobj, "selinux");
2137                return err;
2138        }
2139
2140        selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type);
2141        if (IS_ERR(selinuxfs_mount)) {
2142                pr_err("selinuxfs:  could not mount!\n");
2143                err = PTR_ERR(selinuxfs_mount);
2144                selinuxfs_mount = NULL;
2145        }
2146        selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root,
2147                                                &null_name);
2148        if (IS_ERR(selinux_null.dentry)) {
2149                pr_err("selinuxfs:  could not lookup null!\n");
2150                err = PTR_ERR(selinux_null.dentry);
2151                selinux_null.dentry = NULL;
2152        }
2153
2154        return err;
2155}
2156
2157__initcall(init_sel_fs);
2158
2159#ifdef CONFIG_SECURITY_SELINUX_DISABLE
2160void exit_sel_fs(void)
2161{
2162        sysfs_remove_mount_point(fs_kobj, "selinux");
2163        dput(selinux_null.dentry);
2164        kern_unmount(selinuxfs_mount);
2165        unregister_filesystem(&sel_fs_type);
2166}
2167#endif
2168