security/selinux/selinuxfs.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* Updated: Karl MacMillan <[email protected]>
   3  *
   4  *      Added conditional policy language extensions
   5  *
   6  *  Updated: Hewlett-Packard <[email protected]>
   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 <[email protected]>
  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/namei.h>
  24 #include <linux/init.h>
  25 #include <linux/string.h>
  26 #include <linux/security.h>
  27 #include <linux/major.h>
  28 #include <linux/seq_file.h>
  29 #include <linux/percpu.h>
  30 #include <linux/audit.h>
  31 #include <linux/uaccess.h>
  32 #include <linux/kobject.h>
  33 #include <linux/ctype.h>
  34
  35 /* selinuxfs pseudo filesystem for exporting the security policy API.
  36    Based on the proc code and the fs/nfsd/nfsctl.c code. */
  37
  38 #include "flask.h"
  39 #include "avc.h"
  40 #include "avc_ss.h"
  41 #include "security.h"
  42 #include "objsec.h"
  43 #include "conditional.h"
  44 #include "ima.h"
  45
  46 enum sel_inos {
  47         SEL_ROOT_INO = 2,
  48         SEL_LOAD,       /* load policy */
  49         SEL_ENFORCE,    /* get or set enforcing status */
  50         SEL_CONTEXT,    /* validate context */
  51         SEL_ACCESS,     /* compute access decision */
  52         SEL_CREATE,     /* compute create labeling decision */
  53         SEL_RELABEL,    /* compute relabeling decision */
  54         SEL_USER,       /* compute reachable user contexts */
  55         SEL_POLICYVERS, /* return policy version for this kernel */
  56         SEL_COMMIT_BOOLS, /* commit new boolean values */
  57         SEL_MLS,        /* return if MLS policy is enabled */
  58         SEL_DISABLE,    /* disable SELinux until next reboot */
  59         SEL_MEMBER,     /* compute polyinstantiation membership decision */
  60         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
  61         SEL_COMPAT_NET, /* whether to use old compat network packet controls */
  62         SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
  63         SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
  64         SEL_STATUS,     /* export current status using mmap() */
  65         SEL_POLICY,     /* allow userspace to read the in kernel policy */
  66         SEL_VALIDATE_TRANS, /* compute validatetrans decision */
  67         SEL_INO_NEXT,   /* The next inode number to use */
  68 };
  69
  70 struct selinux_fs_info {
  71         struct dentry *bool_dir;
  72         unsigned int bool_num;
  73         char **bool_pending_names;
  74         int *bool_pending_values;
  75         struct dentry *class_dir;
  76         unsigned long last_class_ino;
  77         bool policy_opened;
  78         struct dentry *policycap_dir;
  79         unsigned long last_ino;
  80         struct super_block *sb;
  81 };
  82
  83 static 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         fsi->last_ino = SEL_INO_NEXT - 1;
  92         fsi->sb = sb;
  93         sb->s_fs_info = fsi;
  94         return 0;
  95 }
  96
  97 static void selinux_fs_info_free(struct super_block *sb)
  98 {
  99         struct selinux_fs_info *fsi = sb->s_fs_info;
 100         unsigned int i;
 101
 102         if (fsi) {
 103                 for (i = 0; i < fsi->bool_num; i++)
 104                         kfree(fsi->bool_pending_names[i]);
 105                 kfree(fsi->bool_pending_names);
 106                 kfree(fsi->bool_pending_values);
 107         }
 108         kfree(sb->s_fs_info);
 109         sb->s_fs_info = NULL;
 110 }
 111
 112 #define SEL_INITCON_INO_OFFSET          0x01000000
 113 #define SEL_BOOL_INO_OFFSET             0x02000000
 114 #define SEL_CLASS_INO_OFFSET            0x04000000
 115 #define SEL_POLICYCAP_INO_OFFSET        0x08000000
 116 #define SEL_INO_MASK                    0x00ffffff
 117
 118 #define BOOL_DIR_NAME "booleans"
 119 #define CLASS_DIR_NAME "class"
 120 #define POLICYCAP_DIR_NAME "policy_capabilities"
 121
 122 #define TMPBUFLEN       12
 123 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
 124                                 size_t count, loff_t *ppos)
 125 {
 126         char tmpbuf[TMPBUFLEN];
 127         ssize_t length;
 128
 129         length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 130                            enforcing_enabled());
 131         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 132 }
 133
 134 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 135 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
 136                                  size_t count, loff_t *ppos)
 137
 138 {
 139         char *page = NULL;
 140         ssize_t length;
 141         int scan_value;
 142         bool 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", &scan_value) != 1)
 157                 goto out;
 158
 159         new_value = !!scan_value;
 160
 161         old_value = enforcing_enabled();
 162         if (new_value != old_value) {
 163                 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 164                                       SECCLASS_SECURITY, SECURITY__SETENFORCE,
 165                                       NULL);
 166                 if (length)
 167                         goto out;
 168                 audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
 169                         "enforcing=%d old_enforcing=%d auid=%u ses=%u"
 170                         " enabled=1 old-enabled=1 lsm=selinux res=1",
 171                         new_value, old_value,
 172                         from_kuid(&init_user_ns, audit_get_loginuid(current)),
 173                         audit_get_sessionid(current));
 174                 enforcing_set(new_value);
 175                 if (new_value)
 176                         avc_ss_reset(0);
 177                 selnl_notify_setenforce(new_value);
 178                 selinux_status_update_setenforce(new_value);
 179                 if (!new_value)
 180                         call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 181
 182                 selinux_ima_measure_state();
 183         }
 184         length = count;
 185 out:
 186         kfree(page);
 187         return length;
 188 }
 189 #else
 190 #define sel_write_enforce NULL
 191 #endif
 192
 193 static const struct file_operations sel_enforce_ops = {
 194         .read           = sel_read_enforce,
 195         .write          = sel_write_enforce,
 196         .llseek         = generic_file_llseek,
 197 };
 198
 199 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
 200                                         size_t count, loff_t *ppos)
 201 {
 202         char tmpbuf[TMPBUFLEN];
 203         ssize_t length;
 204         ino_t ino = file_inode(filp)->i_ino;
 205         int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
 206                 security_get_reject_unknown() :
 207                 !security_get_allow_unknown();
 208
 209         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
 210         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 211 }
 212
 213 static const struct file_operations sel_handle_unknown_ops = {
 214         .read           = sel_read_handle_unknown,
 215         .llseek         = generic_file_llseek,
 216 };
 217
 218 static int sel_open_handle_status(struct inode *inode, struct file *filp)
 219 {
 220         struct page    *status = selinux_kernel_status_page();
 221
 222         if (!status)
 223                 return -ENOMEM;
 224
 225         filp->private_data = status;
 226
 227         return 0;
 228 }
 229
 230 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
 231                                       size_t count, loff_t *ppos)
 232 {
 233         struct page    *status = filp->private_data;
 234
 235         BUG_ON(!status);
 236
 237         return simple_read_from_buffer(buf, count, ppos,
 238                                        page_address(status),
 239                                        sizeof(struct selinux_kernel_status));
 240 }
 241
 242 static int sel_mmap_handle_status(struct file *filp,
 243                                   struct vm_area_struct *vma)
 244 {
 245         struct page    *status = filp->private_data;
 246         unsigned long   size = vma->vm_end - vma->vm_start;
 247
 248         BUG_ON(!status);
 249
 250         /* only allows one page from the head */
 251         if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
 252                 return -EIO;
 253         /* disallow writable mapping */
 254         if (vma->vm_flags & VM_WRITE)
 255                 return -EPERM;
 256         /* disallow mprotect() turns it into writable */
 257         vm_flags_clear(vma, VM_MAYWRITE);
 258
 259         return remap_pfn_range(vma, vma->vm_start,
 260                                page_to_pfn(status),
 261                                size, vma->vm_page_prot);
 262 }
 263
 264 static const struct file_operations sel_handle_status_ops = {
 265         .open           = sel_open_handle_status,
 266         .read           = sel_read_handle_status,
 267         .mmap           = sel_mmap_handle_status,
 268         .llseek         = generic_file_llseek,
 269 };
 270
 271 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
 272                                  size_t count, loff_t *ppos)
 273
 274 {
 275         char *page;
 276         ssize_t length;
 277         int new_value;
 278
 279         if (count >= PAGE_SIZE)
 280                 return -ENOMEM;
 281
 282         /* No partial writes. */
 283         if (*ppos != 0)
 284                 return -EINVAL;
 285
 286         page = memdup_user_nul(buf, count);
 287         if (IS_ERR(page))
 288                 return PTR_ERR(page);
 289
 290         if (sscanf(page, "%d", &new_value) != 1) {
 291                 length = -EINVAL;
 292                 goto out;
 293         }
 294         length = count;
 295
 296         if (new_value) {
 297                 pr_err("SELinux: https://github.com/SELinuxProject/selinux-kernel/wiki/DEPRECATE-runtime-disable\n");
 298                 pr_err("SELinux: Runtime disable is not supported, use selinux=0 on the kernel cmdline.\n");
 299         }
 300
 301 out:
 302         kfree(page);
 303         return length;
 304 }
 305
 306 static const struct file_operations sel_disable_ops = {
 307         .write          = sel_write_disable,
 308         .llseek         = generic_file_llseek,
 309 };
 310
 311 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
 312                                    size_t count, loff_t *ppos)
 313 {
 314         char tmpbuf[TMPBUFLEN];
 315         ssize_t length;
 316
 317         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
 318         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 319 }
 320
 321 static const struct file_operations sel_policyvers_ops = {
 322         .read           = sel_read_policyvers,
 323         .llseek         = generic_file_llseek,
 324 };
 325
 326 /* declaration for sel_write_load */
 327 static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
 328                           unsigned int *bool_num, char ***bool_pending_names,
 329                           int **bool_pending_values);
 330 static int sel_make_classes(struct selinux_policy *newpolicy,
 331                             struct dentry *class_dir,
 332                             unsigned long *last_class_ino);
 333
 334 /* declaration for sel_make_class_dirs */
 335 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
 336                         unsigned long *ino);
 337
 338 /* declaration for sel_make_policy_nodes */
 339 static struct dentry *sel_make_swapover_dir(struct super_block *sb,
 340                                                 unsigned long *ino);
 341
 342 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
 343                                 size_t count, loff_t *ppos)
 344 {
 345         char tmpbuf[TMPBUFLEN];
 346         ssize_t length;
 347
 348         length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 349                            security_mls_enabled());
 350         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 351 }
 352
 353 static const struct file_operations sel_mls_ops = {
 354         .read           = sel_read_mls,
 355         .llseek         = generic_file_llseek,
 356 };
 357
 358 struct policy_load_memory {
 359         size_t len;
 360         void *data;
 361 };
 362
 363 static int sel_open_policy(struct inode *inode, struct file *filp)
 364 {
 365         struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
 366         struct policy_load_memory *plm = NULL;
 367         int rc;
 368
 369         BUG_ON(filp->private_data);
 370
 371         mutex_lock(&selinux_state.policy_mutex);
 372
 373         rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 374                           SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 375         if (rc)
 376                 goto err;
 377
 378         rc = -EBUSY;
 379         if (fsi->policy_opened)
 380                 goto err;
 381
 382         rc = -ENOMEM;
 383         plm = kzalloc(sizeof(*plm), GFP_KERNEL);
 384         if (!plm)
 385                 goto err;
 386
 387         rc = security_read_policy(&plm->data, &plm->len);
 388         if (rc)
 389                 goto err;
 390
 391         if ((size_t)i_size_read(inode) != plm->len) {
 392                 inode_lock(inode);
 393                 i_size_write(inode, plm->len);
 394                 inode_unlock(inode);
 395         }
 396
 397         fsi->policy_opened = 1;
 398
 399         filp->private_data = plm;
 400
 401         mutex_unlock(&selinux_state.policy_mutex);
 402
 403         return 0;
 404 err:
 405         mutex_unlock(&selinux_state.policy_mutex);
 406
 407         if (plm)
 408                 vfree(plm->data);
 409         kfree(plm);
 410         return rc;
 411 }
 412
 413 static int sel_release_policy(struct inode *inode, struct file *filp)
 414 {
 415         struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
 416         struct policy_load_memory *plm = filp->private_data;
 417
 418         BUG_ON(!plm);
 419
 420         fsi->policy_opened = 0;
 421
 422         vfree(plm->data);
 423         kfree(plm);
 424
 425         return 0;
 426 }
 427
 428 static ssize_t sel_read_policy(struct file *filp, char __user *buf,
 429                                size_t count, loff_t *ppos)
 430 {
 431         struct policy_load_memory *plm = filp->private_data;
 432         int ret;
 433
 434         ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 435                           SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 436         if (ret)
 437                 return ret;
 438
 439         return simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
 440 }
 441
 442 static vm_fault_t sel_mmap_policy_fault(struct vm_fault *vmf)
 443 {
 444         struct policy_load_memory *plm = vmf->vma->vm_file->private_data;
 445         unsigned long offset;
 446         struct page *page;
 447
 448         if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
 449                 return VM_FAULT_SIGBUS;
 450
 451         offset = vmf->pgoff << PAGE_SHIFT;
 452         if (offset >= roundup(plm->len, PAGE_SIZE))
 453                 return VM_FAULT_SIGBUS;
 454
 455         page = vmalloc_to_page(plm->data + offset);
 456         get_page(page);
 457
 458         vmf->page = page;
 459
 460         return 0;
 461 }
 462
 463 static const struct vm_operations_struct sel_mmap_policy_ops = {
 464         .fault = sel_mmap_policy_fault,
 465         .page_mkwrite = sel_mmap_policy_fault,
 466 };
 467
 468 static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
 469 {
 470         if (vma->vm_flags & VM_SHARED) {
 471                 /* do not allow mprotect to make mapping writable */
 472                 vm_flags_clear(vma, VM_MAYWRITE);
 473
 474                 if (vma->vm_flags & VM_WRITE)
 475                         return -EACCES;
 476         }
 477
 478         vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
 479         vma->vm_ops = &sel_mmap_policy_ops;
 480
 481         return 0;
 482 }
 483
 484 static const struct file_operations sel_policy_ops = {
 485         .open           = sel_open_policy,
 486         .read           = sel_read_policy,
 487         .mmap           = sel_mmap_policy,
 488         .release        = sel_release_policy,
 489         .llseek         = generic_file_llseek,
 490 };
 491
 492 static void sel_remove_old_bool_data(unsigned int bool_num, char **bool_names,
 493                                      int *bool_values)
 494 {
 495         u32 i;
 496
 497         /* bool_dir cleanup */
 498         for (i = 0; i < bool_num; i++)
 499                 kfree(bool_names[i]);
 500         kfree(bool_names);
 501         kfree(bool_values);
 502 }
 503
 504 static int sel_make_policy_nodes(struct selinux_fs_info *fsi,
 505                                 struct selinux_policy *newpolicy)
 506 {
 507         int ret = 0;
 508         struct dentry *tmp_parent, *tmp_bool_dir, *tmp_class_dir;
 509         unsigned int bool_num = 0;
 510         char **bool_names = NULL;
 511         int *bool_values = NULL;
 512         unsigned long tmp_ino = fsi->last_ino; /* Don't increment last_ino in this function */
 513
 514         tmp_parent = sel_make_swapover_dir(fsi->sb, &tmp_ino);
 515         if (IS_ERR(tmp_parent))
 516                 return PTR_ERR(tmp_parent);
 517
 518         tmp_ino = fsi->bool_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
 519         tmp_bool_dir = sel_make_dir(tmp_parent, BOOL_DIR_NAME, &tmp_ino);
 520         if (IS_ERR(tmp_bool_dir)) {
 521                 ret = PTR_ERR(tmp_bool_dir);
 522                 goto out;
 523         }
 524
 525         tmp_ino = fsi->class_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
 526         tmp_class_dir = sel_make_dir(tmp_parent, CLASS_DIR_NAME, &tmp_ino);
 527         if (IS_ERR(tmp_class_dir)) {
 528                 ret = PTR_ERR(tmp_class_dir);
 529                 goto out;
 530         }
 531
 532         ret = sel_make_bools(newpolicy, tmp_bool_dir, &bool_num,
 533                              &bool_names, &bool_values);
 534         if (ret)
 535                 goto out;
 536
 537         ret = sel_make_classes(newpolicy, tmp_class_dir,
 538                                &fsi->last_class_ino);
 539         if (ret)
 540                 goto out;
 541
 542         lock_rename(tmp_parent, fsi->sb->s_root);
 543
 544         /* booleans */
 545         d_exchange(tmp_bool_dir, fsi->bool_dir);
 546
 547         swap(fsi->bool_num, bool_num);
 548         swap(fsi->bool_pending_names, bool_names);
 549         swap(fsi->bool_pending_values, bool_values);
 550
 551         fsi->bool_dir = tmp_bool_dir;
 552
 553         /* classes */
 554         d_exchange(tmp_class_dir, fsi->class_dir);
 555         fsi->class_dir = tmp_class_dir;
 556
 557         unlock_rename(tmp_parent, fsi->sb->s_root);
 558
 559 out:
 560         sel_remove_old_bool_data(bool_num, bool_names, bool_values);
 561         /* Since the other temporary dirs are children of tmp_parent
 562          * this will handle all the cleanup in the case of a failure before
 563          * the swapover
 564          */
 565         simple_recursive_removal(tmp_parent, NULL);
 566
 567         return ret;
 568 }
 569
 570 static ssize_t sel_write_load(struct file *file, const char __user *buf,
 571                               size_t count, loff_t *ppos)
 572
 573 {
 574         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 575         struct selinux_load_state load_state;
 576         ssize_t length;
 577         void *data = NULL;
 578
 579         mutex_lock(&selinux_state.policy_mutex);
 580
 581         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 582                               SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
 583         if (length)
 584                 goto out;
 585
 586         /* No partial writes. */
 587         length = -EINVAL;
 588         if (*ppos != 0)
 589                 goto out;
 590
 591         length = -ENOMEM;
 592         data = vmalloc(count);
 593         if (!data)
 594                 goto out;
 595
 596         length = -EFAULT;
 597         if (copy_from_user(data, buf, count) != 0)
 598                 goto out;
 599
 600         length = security_load_policy(data, count, &load_state);
 601         if (length) {
 602                 pr_warn_ratelimited("SELinux: failed to load policy\n");
 603                 goto out;
 604         }
 605
 606         length = sel_make_policy_nodes(fsi, load_state.policy);
 607         if (length) {
 608                 pr_warn_ratelimited("SELinux: failed to initialize selinuxfs\n");
 609                 selinux_policy_cancel(&load_state);
 610                 goto out;
 611         }
 612
 613         selinux_policy_commit(&load_state);
 614
 615         length = count;
 616
 617         audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
 618                 "auid=%u ses=%u lsm=selinux res=1",
 619                 from_kuid(&init_user_ns, audit_get_loginuid(current)),
 620                 audit_get_sessionid(current));
 621 out:
 622         mutex_unlock(&selinux_state.policy_mutex);
 623         vfree(data);
 624         return length;
 625 }
 626
 627 static const struct file_operations sel_load_ops = {
 628         .write          = sel_write_load,
 629         .llseek         = generic_file_llseek,
 630 };
 631
 632 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
 633 {
 634         char *canon = NULL;
 635         u32 sid, len;
 636         ssize_t length;
 637
 638         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 639                               SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
 640         if (length)
 641                 goto out;
 642
 643         length = security_context_to_sid(buf, size, &sid, GFP_KERNEL);
 644         if (length)
 645                 goto out;
 646
 647         length = security_sid_to_context(sid, &canon, &len);
 648         if (length)
 649                 goto out;
 650
 651         length = -ERANGE;
 652         if (len > SIMPLE_TRANSACTION_LIMIT) {
 653                 pr_err("SELinux: %s:  context size (%u) exceeds "
 654                         "payload max\n", __func__, len);
 655                 goto out;
 656         }
 657
 658         memcpy(buf, canon, len);
 659         length = len;
 660 out:
 661         kfree(canon);
 662         return length;
 663 }
 664
 665 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
 666                                      size_t count, loff_t *ppos)
 667 {
 668         char tmpbuf[TMPBUFLEN];
 669         ssize_t length;
 670
 671         length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
 672                            checkreqprot_get());
 673         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 674 }
 675
 676 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
 677                                       size_t count, loff_t *ppos)
 678 {
 679         char *page;
 680         ssize_t length;
 681         unsigned int new_value;
 682
 683         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 684                               SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
 685                               NULL);
 686         if (length)
 687                 return length;
 688
 689         if (count >= PAGE_SIZE)
 690                 return -ENOMEM;
 691
 692         /* No partial writes. */
 693         if (*ppos != 0)
 694                 return -EINVAL;
 695
 696         page = memdup_user_nul(buf, count);
 697         if (IS_ERR(page))
 698                 return PTR_ERR(page);
 699
 700         if (sscanf(page, "%u", &new_value) != 1) {
 701                 length = -EINVAL;
 702                 goto out;
 703         }
 704         length = count;
 705
 706         if (new_value) {
 707                 char comm[sizeof(current->comm)];
 708
 709                 memcpy(comm, current->comm, sizeof(comm));
 710                 pr_err("SELinux: %s (%d) set checkreqprot to 1. This is no longer supported.\n",
 711                        comm, current->pid);
 712         }
 713
 714         selinux_ima_measure_state();
 715
 716 out:
 717         kfree(page);
 718         return length;
 719 }
 720 static const struct file_operations sel_checkreqprot_ops = {
 721         .read           = sel_read_checkreqprot,
 722         .write          = sel_write_checkreqprot,
 723         .llseek         = generic_file_llseek,
 724 };
 725
 726 static ssize_t sel_write_validatetrans(struct file *file,
 727                                         const char __user *buf,
 728                                         size_t count, loff_t *ppos)
 729 {
 730         char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
 731         char *req = NULL;
 732         u32 osid, nsid, tsid;
 733         u16 tclass;
 734         int rc;
 735
 736         rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 737                           SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
 738         if (rc)
 739                 goto out;
 740
 741         rc = -ENOMEM;
 742         if (count >= PAGE_SIZE)
 743                 goto out;
 744
 745         /* No partial writes. */
 746         rc = -EINVAL;
 747         if (*ppos != 0)
 748                 goto out;
 749
 750         req = memdup_user_nul(buf, count);
 751         if (IS_ERR(req)) {
 752                 rc = PTR_ERR(req);
 753                 req = NULL;
 754                 goto out;
 755         }
 756
 757         rc = -ENOMEM;
 758         oldcon = kzalloc(count + 1, GFP_KERNEL);
 759         if (!oldcon)
 760                 goto out;
 761
 762         newcon = kzalloc(count + 1, GFP_KERNEL);
 763         if (!newcon)
 764                 goto out;
 765
 766         taskcon = kzalloc(count + 1, GFP_KERNEL);
 767         if (!taskcon)
 768                 goto out;
 769
 770         rc = -EINVAL;
 771         if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
 772                 goto out;
 773
 774         rc = security_context_str_to_sid(oldcon, &osid, GFP_KERNEL);
 775         if (rc)
 776                 goto out;
 777
 778         rc = security_context_str_to_sid(newcon, &nsid, GFP_KERNEL);
 779         if (rc)
 780                 goto out;
 781
 782         rc = security_context_str_to_sid(taskcon, &tsid, GFP_KERNEL);
 783         if (rc)
 784                 goto out;
 785
 786         rc = security_validate_transition_user(osid, nsid, tsid, tclass);
 787         if (!rc)
 788                 rc = count;
 789 out:
 790         kfree(req);
 791         kfree(oldcon);
 792         kfree(newcon);
 793         kfree(taskcon);
 794         return rc;
 795 }
 796
 797 static const struct file_operations sel_transition_ops = {
 798         .write          = sel_write_validatetrans,
 799         .llseek         = generic_file_llseek,
 800 };
 801
 802 /*
 803  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 804  */
 805 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
 806 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
 807 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
 808 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
 809 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
 810
 811 static ssize_t (*const write_op[])(struct file *, char *, size_t) = {
 812         [SEL_ACCESS] = sel_write_access,
 813         [SEL_CREATE] = sel_write_create,
 814         [SEL_RELABEL] = sel_write_relabel,
 815         [SEL_USER] = sel_write_user,
 816         [SEL_MEMBER] = sel_write_member,
 817         [SEL_CONTEXT] = sel_write_context,
 818 };
 819
 820 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 821 {
 822         ino_t ino = file_inode(file)->i_ino;
 823         char *data;
 824         ssize_t rv;
 825
 826         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
 827                 return -EINVAL;
 828
 829         data = simple_transaction_get(file, buf, size);
 830         if (IS_ERR(data))
 831                 return PTR_ERR(data);
 832
 833         rv = write_op[ino](file, data, size);
 834         if (rv > 0) {
 835                 simple_transaction_set(file, rv);
 836                 rv = size;
 837         }
 838         return rv;
 839 }
 840
 841 static const struct file_operations transaction_ops = {
 842         .write          = selinux_transaction_write,
 843         .read           = simple_transaction_read,
 844         .release        = simple_transaction_release,
 845         .llseek         = generic_file_llseek,
 846 };
 847
 848 /*
 849  * payload - write methods
 850  * If the method has a response, the response should be put in buf,
 851  * and the length returned.  Otherwise return 0 or and -error.
 852  */
 853
 854 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
 855 {
 856         char *scon = NULL, *tcon = NULL;
 857         u32 ssid, tsid;
 858         u16 tclass;
 859         struct av_decision avd;
 860         ssize_t length;
 861
 862         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 863                               SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
 864         if (length)
 865                 goto out;
 866
 867         length = -ENOMEM;
 868         scon = kzalloc(size + 1, GFP_KERNEL);
 869         if (!scon)
 870                 goto out;
 871
 872         length = -ENOMEM;
 873         tcon = kzalloc(size + 1, GFP_KERNEL);
 874         if (!tcon)
 875                 goto out;
 876
 877         length = -EINVAL;
 878         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 879                 goto out;
 880
 881         length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
 882         if (length)
 883                 goto out;
 884
 885         length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
 886         if (length)
 887                 goto out;
 888
 889         security_compute_av_user(ssid, tsid, tclass, &avd);
 890
 891         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 892                           "%x %x %x %x %u %x",
 893                           avd.allowed, 0xffffffff,
 894                           avd.auditallow, avd.auditdeny,
 895                           avd.seqno, avd.flags);
 896 out:
 897         kfree(tcon);
 898         kfree(scon);
 899         return length;
 900 }
 901
 902 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
 903 {
 904         char *scon = NULL, *tcon = NULL;
 905         char *namebuf = NULL, *objname = NULL;
 906         u32 ssid, tsid, newsid;
 907         u16 tclass;
 908         ssize_t length;
 909         char *newcon = NULL;
 910         u32 len;
 911         int nargs;
 912
 913         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 914                               SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
 915                               NULL);
 916         if (length)
 917                 goto out;
 918
 919         length = -ENOMEM;
 920         scon = kzalloc(size + 1, GFP_KERNEL);
 921         if (!scon)
 922                 goto out;
 923
 924         length = -ENOMEM;
 925         tcon = kzalloc(size + 1, GFP_KERNEL);
 926         if (!tcon)
 927                 goto out;
 928
 929         length = -ENOMEM;
 930         namebuf = kzalloc(size + 1, GFP_KERNEL);
 931         if (!namebuf)
 932                 goto out;
 933
 934         length = -EINVAL;
 935         nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
 936         if (nargs < 3 || nargs > 4)
 937                 goto out;
 938         if (nargs == 4) {
 939                 /*
 940                  * If and when the name of new object to be queried contains
 941                  * either whitespace or multibyte characters, they shall be
 942                  * encoded based on the percentage-encoding rule.
 943                  * If not encoded, the sscanf logic picks up only left-half
 944                  * of the supplied name; split by a whitespace unexpectedly.
 945                  */
 946                 char   *r, *w;
 947                 int     c1, c2;
 948
 949                 r = w = namebuf;
 950                 do {
 951                         c1 = *r++;
 952                         if (c1 == '+')
 953                                 c1 = ' ';
 954                         else if (c1 == '%') {
 955                                 c1 = hex_to_bin(*r++);
 956                                 if (c1 < 0)
 957                                         goto out;
 958                                 c2 = hex_to_bin(*r++);
 959                                 if (c2 < 0)
 960                                         goto out;
 961                                 c1 = (c1 << 4) | c2;
 962                         }
 963                         *w++ = c1;
 964                 } while (c1 != '\0');
 965
 966                 objname = namebuf;
 967         }
 968
 969         length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
 970         if (length)
 971                 goto out;
 972
 973         length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
 974         if (length)
 975                 goto out;
 976
 977         length = security_transition_sid_user(ssid, tsid, tclass,
 978                                               objname, &newsid);
 979         if (length)
 980                 goto out;
 981
 982         length = security_sid_to_context(newsid, &newcon, &len);
 983         if (length)
 984                 goto out;
 985
 986         length = -ERANGE;
 987         if (len > SIMPLE_TRANSACTION_LIMIT) {
 988                 pr_err("SELinux: %s:  context size (%u) exceeds "
 989                         "payload max\n", __func__, len);
 990                 goto out;
 991         }
 992
 993         memcpy(buf, newcon, len);
 994         length = len;
 995 out:
 996         kfree(newcon);
 997         kfree(namebuf);
 998         kfree(tcon);
 999         kfree(scon);
1000         return length;
1001 }
1002
1003 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
1004 {
1005         char *scon = NULL, *tcon = NULL;
1006         u32 ssid, tsid, newsid;
1007         u16 tclass;
1008         ssize_t length;
1009         char *newcon = NULL;
1010         u32 len;
1011
1012         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1013                               SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
1014                               NULL);
1015         if (length)
1016                 goto out;
1017
1018         length = -ENOMEM;
1019         scon = kzalloc(size + 1, GFP_KERNEL);
1020         if (!scon)
1021                 goto out;
1022
1023         length = -ENOMEM;
1024         tcon = kzalloc(size + 1, GFP_KERNEL);
1025         if (!tcon)
1026                 goto out;
1027
1028         length = -EINVAL;
1029         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1030                 goto out;
1031
1032         length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
1033         if (length)
1034                 goto out;
1035
1036         length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
1037         if (length)
1038                 goto out;
1039
1040         length = security_change_sid(ssid, tsid, tclass, &newsid);
1041         if (length)
1042                 goto out;
1043
1044         length = security_sid_to_context(newsid, &newcon, &len);
1045         if (length)
1046                 goto out;
1047
1048         length = -ERANGE;
1049         if (len > SIMPLE_TRANSACTION_LIMIT)
1050                 goto out;
1051
1052         memcpy(buf, newcon, len);
1053         length = len;
1054 out:
1055         kfree(newcon);
1056         kfree(tcon);
1057         kfree(scon);
1058         return length;
1059 }
1060
1061 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
1062 {
1063         char *con = NULL, *user = NULL, *ptr;
1064         u32 sid, *sids = NULL;
1065         ssize_t length;
1066         char *newcon;
1067         int rc;
1068         u32 i, len, nsids;
1069
1070         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1071                               SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
1072                               NULL);
1073         if (length)
1074                 goto out;
1075
1076         length = -ENOMEM;
1077         con = kzalloc(size + 1, GFP_KERNEL);
1078         if (!con)
1079                 goto out;
1080
1081         length = -ENOMEM;
1082         user = kzalloc(size + 1, GFP_KERNEL);
1083         if (!user)
1084                 goto out;
1085
1086         length = -EINVAL;
1087         if (sscanf(buf, "%s %s", con, user) != 2)
1088                 goto out;
1089
1090         length = security_context_str_to_sid(con, &sid, GFP_KERNEL);
1091         if (length)
1092                 goto out;
1093
1094         length = security_get_user_sids(sid, user, &sids, &nsids);
1095         if (length)
1096                 goto out;
1097
1098         length = sprintf(buf, "%u", nsids) + 1;
1099         ptr = buf + length;
1100         for (i = 0; i < nsids; i++) {
1101                 rc = security_sid_to_context(sids[i], &newcon, &len);
1102                 if (rc) {
1103                         length = rc;
1104                         goto out;
1105                 }
1106                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1107                         kfree(newcon);
1108                         length = -ERANGE;
1109                         goto out;
1110                 }
1111                 memcpy(ptr, newcon, len);
1112                 kfree(newcon);
1113                 ptr += len;
1114                 length += len;
1115         }
1116 out:
1117         kfree(sids);
1118         kfree(user);
1119         kfree(con);
1120         return length;
1121 }
1122
1123 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1124 {
1125         char *scon = NULL, *tcon = NULL;
1126         u32 ssid, tsid, newsid;
1127         u16 tclass;
1128         ssize_t length;
1129         char *newcon = NULL;
1130         u32 len;
1131
1132         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1133                               SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
1134                               NULL);
1135         if (length)
1136                 goto out;
1137
1138         length = -ENOMEM;
1139         scon = kzalloc(size + 1, GFP_KERNEL);
1140         if (!scon)
1141                 goto out;
1142
1143         length = -ENOMEM;
1144         tcon = kzalloc(size + 1, GFP_KERNEL);
1145         if (!tcon)
1146                 goto out;
1147
1148         length = -EINVAL;
1149         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1150                 goto out;
1151
1152         length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
1153         if (length)
1154                 goto out;
1155
1156         length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
1157         if (length)
1158                 goto out;
1159
1160         length = security_member_sid(ssid, tsid, tclass, &newsid);
1161         if (length)
1162                 goto out;
1163
1164         length = security_sid_to_context(newsid, &newcon, &len);
1165         if (length)
1166                 goto out;
1167
1168         length = -ERANGE;
1169         if (len > SIMPLE_TRANSACTION_LIMIT) {
1170                 pr_err("SELinux: %s:  context size (%u) exceeds "
1171                         "payload max\n", __func__, len);
1172                 goto out;
1173         }
1174
1175         memcpy(buf, newcon, len);
1176         length = len;
1177 out:
1178         kfree(newcon);
1179         kfree(tcon);
1180         kfree(scon);
1181         return length;
1182 }
1183
1184 static struct inode *sel_make_inode(struct super_block *sb, umode_t mode)
1185 {
1186         struct inode *ret = new_inode(sb);
1187
1188         if (ret) {
1189                 ret->i_mode = mode;
1190                 simple_inode_init_ts(ret);
1191         }
1192         return ret;
1193 }
1194
1195 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1196                              size_t count, loff_t *ppos)
1197 {
1198         struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1199         char *page = NULL;
1200         ssize_t length;
1201         ssize_t ret;
1202         int cur_enforcing;
1203         unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1204         const char *name = filep->f_path.dentry->d_name.name;
1205
1206         mutex_lock(&selinux_state.policy_mutex);
1207
1208         ret = -EINVAL;
1209         if (index >= fsi->bool_num || strcmp(name,
1210                                              fsi->bool_pending_names[index]))
1211                 goto out_unlock;
1212
1213         ret = -ENOMEM;
1214         page = (char *)get_zeroed_page(GFP_KERNEL);
1215         if (!page)
1216                 goto out_unlock;
1217
1218         cur_enforcing = security_get_bool_value(index);
1219         if (cur_enforcing < 0) {
1220                 ret = cur_enforcing;
1221                 goto out_unlock;
1222         }
1223         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1224                           fsi->bool_pending_values[index]);
1225         mutex_unlock(&selinux_state.policy_mutex);
1226         ret = simple_read_from_buffer(buf, count, ppos, page, length);
1227 out_free:
1228         free_page((unsigned long)page);
1229         return ret;
1230
1231 out_unlock:
1232         mutex_unlock(&selinux_state.policy_mutex);
1233         goto out_free;
1234 }
1235
1236 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1237                               size_t count, loff_t *ppos)
1238 {
1239         struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1240         char *page = NULL;
1241         ssize_t length;
1242         int new_value;
1243         unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1244         const char *name = filep->f_path.dentry->d_name.name;
1245
1246         if (count >= PAGE_SIZE)
1247                 return -ENOMEM;
1248
1249         /* No partial writes. */
1250         if (*ppos != 0)
1251                 return -EINVAL;
1252
1253         page = memdup_user_nul(buf, count);
1254         if (IS_ERR(page))
1255                 return PTR_ERR(page);
1256
1257         mutex_lock(&selinux_state.policy_mutex);
1258
1259         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1260                               SECCLASS_SECURITY, SECURITY__SETBOOL,
1261                               NULL);
1262         if (length)
1263                 goto out;
1264
1265         length = -EINVAL;
1266         if (index >= fsi->bool_num || strcmp(name,
1267                                              fsi->bool_pending_names[index]))
1268                 goto out;
1269
1270         length = -EINVAL;
1271         if (sscanf(page, "%d", &new_value) != 1)
1272                 goto out;
1273
1274         if (new_value)
1275                 new_value = 1;
1276
1277         fsi->bool_pending_values[index] = new_value;
1278         length = count;
1279
1280 out:
1281         mutex_unlock(&selinux_state.policy_mutex);
1282         kfree(page);
1283         return length;
1284 }
1285
1286 static const struct file_operations sel_bool_ops = {
1287         .read           = sel_read_bool,
1288         .write          = sel_write_bool,
1289         .llseek         = generic_file_llseek,
1290 };
1291
1292 static ssize_t sel_commit_bools_write(struct file *filep,
1293                                       const char __user *buf,
1294                                       size_t count, loff_t *ppos)
1295 {
1296         struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1297         char *page = NULL;
1298         ssize_t length;
1299         int new_value;
1300
1301         if (count >= PAGE_SIZE)
1302                 return -ENOMEM;
1303
1304         /* No partial writes. */
1305         if (*ppos != 0)
1306                 return -EINVAL;
1307
1308         page = memdup_user_nul(buf, count);
1309         if (IS_ERR(page))
1310                 return PTR_ERR(page);
1311
1312         mutex_lock(&selinux_state.policy_mutex);
1313
1314         length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1315                               SECCLASS_SECURITY, SECURITY__SETBOOL,
1316                               NULL);
1317         if (length)
1318                 goto out;
1319
1320         length = -EINVAL;
1321         if (sscanf(page, "%d", &new_value) != 1)
1322                 goto out;
1323
1324         length = 0;
1325         if (new_value && fsi->bool_pending_values)
1326                 length = security_set_bools(fsi->bool_num,
1327                                             fsi->bool_pending_values);
1328
1329         if (!length)
1330                 length = count;
1331
1332 out:
1333         mutex_unlock(&selinux_state.policy_mutex);
1334         kfree(page);
1335         return length;
1336 }
1337
1338 static const struct file_operations sel_commit_bools_ops = {
1339         .write          = sel_commit_bools_write,
1340         .llseek         = generic_file_llseek,
1341 };
1342
1343 static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
1344                           unsigned int *bool_num, char ***bool_pending_names,
1345                           int **bool_pending_values)
1346 {
1347         int ret;
1348         char **names, *page;
1349         u32 i, num;
1350
1351         page = (char *)get_zeroed_page(GFP_KERNEL);
1352         if (!page)
1353                 return -ENOMEM;
1354
1355         ret = security_get_bools(newpolicy, &num, &names, bool_pending_values);
1356         if (ret)
1357                 goto out;
1358
1359         *bool_num = num;
1360         *bool_pending_names = names;
1361
1362         for (i = 0; i < num; i++) {
1363                 struct dentry *dentry;
1364                 struct inode *inode;
1365                 struct inode_security_struct *isec;
1366                 ssize_t len;
1367                 u32 sid;
1368
1369                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1370                 if (len >= PAGE_SIZE) {
1371                         ret = -ENAMETOOLONG;
1372                         break;
1373                 }
1374                 dentry = d_alloc_name(bool_dir, names[i]);
1375                 if (!dentry) {
1376                         ret = -ENOMEM;
1377                         break;
1378                 }
1379
1380                 inode = sel_make_inode(bool_dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1381                 if (!inode) {
1382                         dput(dentry);
1383                         ret = -ENOMEM;
1384                         break;
1385                 }
1386
1387                 isec = selinux_inode(inode);
1388                 ret = selinux_policy_genfs_sid(newpolicy, "selinuxfs", page,
1389                                          SECCLASS_FILE, &sid);
1390                 if (ret) {
1391                         pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
1392                                            page);
1393                         sid = SECINITSID_SECURITY;
1394                 }
1395
1396                 isec->sid = sid;
1397                 isec->initialized = LABEL_INITIALIZED;
1398                 inode->i_fop = &sel_bool_ops;
1399                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1400                 d_add(dentry, inode);
1401         }
1402 out:
1403         free_page((unsigned long)page);
1404         return ret;
1405 }
1406
1407 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1408                                             size_t count, loff_t *ppos)
1409 {
1410         char tmpbuf[TMPBUFLEN];
1411         ssize_t length;
1412
1413         length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1414                            avc_get_cache_threshold());
1415         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1416 }
1417
1418 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1419                                              const char __user *buf,
1420                                              size_t count, loff_t *ppos)
1421
1422 {
1423         char *page;
1424         ssize_t ret;
1425         unsigned int new_value;
1426
1427         ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1428                            SECCLASS_SECURITY, SECURITY__SETSECPARAM,
1429                            NULL);
1430         if (ret)
1431                 return ret;
1432
1433         if (count >= PAGE_SIZE)
1434                 return -ENOMEM;
1435
1436         /* No partial writes. */
1437         if (*ppos != 0)
1438                 return -EINVAL;
1439
1440         page = memdup_user_nul(buf, count);
1441         if (IS_ERR(page))
1442                 return PTR_ERR(page);
1443
1444         ret = -EINVAL;
1445         if (sscanf(page, "%u", &new_value) != 1)
1446                 goto out;
1447
1448         avc_set_cache_threshold(new_value);
1449
1450         ret = count;
1451 out:
1452         kfree(page);
1453         return ret;
1454 }
1455
1456 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1457                                        size_t count, loff_t *ppos)
1458 {
1459         char *page;
1460         ssize_t length;
1461
1462         page = (char *)__get_free_page(GFP_KERNEL);
1463         if (!page)
1464                 return -ENOMEM;
1465
1466         length = avc_get_hash_stats(page);
1467         if (length >= 0)
1468                 length = simple_read_from_buffer(buf, count, ppos, page, length);
1469         free_page((unsigned long)page);
1470
1471         return length;
1472 }
1473
1474 static ssize_t sel_read_sidtab_hash_stats(struct file *filp, char __user *buf,
1475                                         size_t count, loff_t *ppos)
1476 {
1477         char *page;
1478         ssize_t length;
1479
1480         page = (char *)__get_free_page(GFP_KERNEL);
1481         if (!page)
1482                 return -ENOMEM;
1483
1484         length = security_sidtab_hash_stats(page);
1485         if (length >= 0)
1486                 length = simple_read_from_buffer(buf, count, ppos, page,
1487                                                 length);
1488         free_page((unsigned long)page);
1489
1490         return length;
1491 }
1492
1493 static const struct file_operations sel_sidtab_hash_stats_ops = {
1494         .read           = sel_read_sidtab_hash_stats,
1495         .llseek         = generic_file_llseek,
1496 };
1497
1498 static const struct file_operations sel_avc_cache_threshold_ops = {
1499         .read           = sel_read_avc_cache_threshold,
1500         .write          = sel_write_avc_cache_threshold,
1501         .llseek         = generic_file_llseek,
1502 };
1503
1504 static const struct file_operations sel_avc_hash_stats_ops = {
1505         .read           = sel_read_avc_hash_stats,
1506         .llseek         = generic_file_llseek,
1507 };
1508
1509 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1510 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1511 {
1512         int cpu;
1513
1514         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1515                 if (!cpu_possible(cpu))
1516                         continue;
1517                 *idx = cpu + 1;
1518                 return &per_cpu(avc_cache_stats, cpu);
1519         }
1520         (*idx)++;
1521         return NULL;
1522 }
1523
1524 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1525 {
1526         loff_t n = *pos - 1;
1527
1528         if (*pos == 0)
1529                 return SEQ_START_TOKEN;
1530
1531         return sel_avc_get_stat_idx(&n);
1532 }
1533
1534 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1535 {
1536         return sel_avc_get_stat_idx(pos);
1537 }
1538
1539 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1540 {
1541         struct avc_cache_stats *st = v;
1542
1543         if (v == SEQ_START_TOKEN) {
1544                 seq_puts(seq,
1545                          "lookups hits misses allocations reclaims frees\n");
1546         } else {
1547                 unsigned int lookups = st->lookups;
1548                 unsigned int misses = st->misses;
1549                 unsigned int hits = lookups - misses;
1550                 seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1551                            hits, misses, st->allocations,
1552                            st->reclaims, st->frees);
1553         }
1554         return 0;
1555 }
1556
1557 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1558 { }
1559
1560 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1561         .start          = sel_avc_stats_seq_start,
1562         .next           = sel_avc_stats_seq_next,
1563         .show           = sel_avc_stats_seq_show,
1564         .stop           = sel_avc_stats_seq_stop,
1565 };
1566
1567 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1568 {
1569         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1570 }
1571
1572 static const struct file_operations sel_avc_cache_stats_ops = {
1573         .open           = sel_open_avc_cache_stats,
1574         .read           = seq_read,
1575         .llseek         = seq_lseek,
1576         .release        = seq_release,
1577 };
1578 #endif
1579
1580 static int sel_make_avc_files(struct dentry *dir)
1581 {
1582         struct super_block *sb = dir->d_sb;
1583         struct selinux_fs_info *fsi = sb->s_fs_info;
1584         unsigned int i;
1585         static const struct tree_descr files[] = {
1586                 { "cache_threshold",
1587                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1588                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1589 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1590                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1591 #endif
1592         };
1593
1594         for (i = 0; i < ARRAY_SIZE(files); i++) {
1595                 struct inode *inode;
1596                 struct dentry *dentry;
1597
1598                 dentry = d_alloc_name(dir, files[i].name);
1599                 if (!dentry)
1600                         return -ENOMEM;
1601
1602                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1603                 if (!inode) {
1604                         dput(dentry);
1605                         return -ENOMEM;
1606                 }
1607
1608                 inode->i_fop = files[i].ops;
1609                 inode->i_ino = ++fsi->last_ino;
1610                 d_add(dentry, inode);
1611         }
1612
1613         return 0;
1614 }
1615
1616 static int sel_make_ss_files(struct dentry *dir)
1617 {
1618         struct super_block *sb = dir->d_sb;
1619         struct selinux_fs_info *fsi = sb->s_fs_info;
1620         unsigned int i;
1621         static const struct tree_descr files[] = {
1622                 { "sidtab_hash_stats", &sel_sidtab_hash_stats_ops, S_IRUGO },
1623         };
1624
1625         for (i = 0; i < ARRAY_SIZE(files); i++) {
1626                 struct inode *inode;
1627                 struct dentry *dentry;
1628
1629                 dentry = d_alloc_name(dir, files[i].name);
1630                 if (!dentry)
1631                         return -ENOMEM;
1632
1633                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1634                 if (!inode) {
1635                         dput(dentry);
1636                         return -ENOMEM;
1637                 }
1638
1639                 inode->i_fop = files[i].ops;
1640                 inode->i_ino = ++fsi->last_ino;
1641                 d_add(dentry, inode);
1642         }
1643
1644         return 0;
1645 }
1646
1647 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1648                                 size_t count, loff_t *ppos)
1649 {
1650         char *con;
1651         u32 sid, len;
1652         ssize_t ret;
1653
1654         sid = file_inode(file)->i_ino&SEL_INO_MASK;
1655         ret = security_sid_to_context(sid, &con, &len);
1656         if (ret)
1657                 return ret;
1658
1659         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1660         kfree(con);
1661         return ret;
1662 }
1663
1664 static const struct file_operations sel_initcon_ops = {
1665         .read           = sel_read_initcon,
1666         .llseek         = generic_file_llseek,
1667 };
1668
1669 static int sel_make_initcon_files(struct dentry *dir)
1670 {
1671         unsigned int i;
1672
1673         for (i = 1; i <= SECINITSID_NUM; i++) {
1674                 struct inode *inode;
1675                 struct dentry *dentry;
1676                 const char *s = security_get_initial_sid_context(i);
1677
1678                 if (!s)
1679                         continue;
1680                 dentry = d_alloc_name(dir, s);
1681                 if (!dentry)
1682                         return -ENOMEM;
1683
1684                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1685                 if (!inode) {
1686                         dput(dentry);
1687                         return -ENOMEM;
1688                 }
1689
1690                 inode->i_fop = &sel_initcon_ops;
1691                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1692                 d_add(dentry, inode);
1693         }
1694
1695         return 0;
1696 }
1697
1698 static inline unsigned long sel_class_to_ino(u16 class)
1699 {
1700         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1701 }
1702
1703 static inline u16 sel_ino_to_class(unsigned long ino)
1704 {
1705         return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1706 }
1707
1708 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1709 {
1710         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1711 }
1712
1713 static inline u32 sel_ino_to_perm(unsigned long ino)
1714 {
1715         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1716 }
1717
1718 static ssize_t sel_read_class(struct file *file, char __user *buf,
1719                                 size_t count, loff_t *ppos)
1720 {
1721         unsigned long ino = file_inode(file)->i_ino;
1722         char res[TMPBUFLEN];
1723         ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1724         return simple_read_from_buffer(buf, count, ppos, res, len);
1725 }
1726
1727 static const struct file_operations sel_class_ops = {
1728         .read           = sel_read_class,
1729         .llseek         = generic_file_llseek,
1730 };
1731
1732 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1733                                 size_t count, loff_t *ppos)
1734 {
1735         unsigned long ino = file_inode(file)->i_ino;
1736         char res[TMPBUFLEN];
1737         ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1738         return simple_read_from_buffer(buf, count, ppos, res, len);
1739 }
1740
1741 static const struct file_operations sel_perm_ops = {
1742         .read           = sel_read_perm,
1743         .llseek         = generic_file_llseek,
1744 };
1745
1746 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1747                                   size_t count, loff_t *ppos)
1748 {
1749         int value;
1750         char tmpbuf[TMPBUFLEN];
1751         ssize_t length;
1752         unsigned long i_ino = file_inode(file)->i_ino;
1753
1754         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1755         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1756
1757         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1758 }
1759
1760 static const struct file_operations sel_policycap_ops = {
1761         .read           = sel_read_policycap,
1762         .llseek         = generic_file_llseek,
1763 };
1764
1765 static int sel_make_perm_files(struct selinux_policy *newpolicy,
1766                         char *objclass, int classvalue,
1767                         struct dentry *dir)
1768 {
1769         u32 i, nperms;
1770         int rc;
1771         char **perms;
1772
1773         rc = security_get_permissions(newpolicy, objclass, &perms, &nperms);
1774         if (rc)
1775                 return rc;
1776
1777         for (i = 0; i < nperms; i++) {
1778                 struct inode *inode;
1779                 struct dentry *dentry;
1780
1781                 rc = -ENOMEM;
1782                 dentry = d_alloc_name(dir, perms[i]);
1783                 if (!dentry)
1784                         goto out;
1785
1786                 rc = -ENOMEM;
1787                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1788                 if (!inode) {
1789                         dput(dentry);
1790                         goto out;
1791                 }
1792
1793                 inode->i_fop = &sel_perm_ops;
1794                 /* i+1 since perm values are 1-indexed */
1795                 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1796                 d_add(dentry, inode);
1797         }
1798         rc = 0;
1799 out:
1800         for (i = 0; i < nperms; i++)
1801                 kfree(perms[i]);
1802         kfree(perms);
1803         return rc;
1804 }
1805
1806 static int sel_make_class_dir_entries(struct selinux_policy *newpolicy,
1807                                 char *classname, int index,
1808                                 struct dentry *dir)
1809 {
1810         struct super_block *sb = dir->d_sb;
1811         struct selinux_fs_info *fsi = sb->s_fs_info;
1812         struct dentry *dentry = NULL;
1813         struct inode *inode = NULL;
1814
1815         dentry = d_alloc_name(dir, "index");
1816         if (!dentry)
1817                 return -ENOMEM;
1818
1819         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1820         if (!inode) {
1821                 dput(dentry);
1822                 return -ENOMEM;
1823         }
1824
1825         inode->i_fop = &sel_class_ops;
1826         inode->i_ino = sel_class_to_ino(index);
1827         d_add(dentry, inode);
1828
1829         dentry = sel_make_dir(dir, "perms", &fsi->last_class_ino);
1830         if (IS_ERR(dentry))
1831                 return PTR_ERR(dentry);
1832
1833         return sel_make_perm_files(newpolicy, classname, index, dentry);
1834 }
1835
1836 static int sel_make_classes(struct selinux_policy *newpolicy,
1837                             struct dentry *class_dir,
1838                             unsigned long *last_class_ino)
1839 {
1840         u32 i, nclasses;
1841         int rc;
1842         char **classes;
1843
1844         rc = security_get_classes(newpolicy, &classes, &nclasses);
1845         if (rc)
1846                 return rc;
1847
1848         /* +2 since classes are 1-indexed */
1849         *last_class_ino = sel_class_to_ino(nclasses + 2);
1850
1851         for (i = 0; i < nclasses; i++) {
1852                 struct dentry *class_name_dir;
1853
1854                 class_name_dir = sel_make_dir(class_dir, classes[i],
1855                                               last_class_ino);
1856                 if (IS_ERR(class_name_dir)) {
1857                         rc = PTR_ERR(class_name_dir);
1858                         goto out;
1859                 }
1860
1861                 /* i+1 since class values are 1-indexed */
1862                 rc = sel_make_class_dir_entries(newpolicy, classes[i], i + 1,
1863                                 class_name_dir);
1864                 if (rc)
1865                         goto out;
1866         }
1867         rc = 0;
1868 out:
1869         for (i = 0; i < nclasses; i++)
1870                 kfree(classes[i]);
1871         kfree(classes);
1872         return rc;
1873 }
1874
1875 static int sel_make_policycap(struct selinux_fs_info *fsi)
1876 {
1877         unsigned int iter;
1878         struct dentry *dentry = NULL;
1879         struct inode *inode = NULL;
1880
1881         for (iter = 0; iter <= POLICYDB_CAP_MAX; iter++) {
1882                 if (iter < ARRAY_SIZE(selinux_policycap_names))
1883                         dentry = d_alloc_name(fsi->policycap_dir,
1884                                               selinux_policycap_names[iter]);
1885                 else
1886                         dentry = d_alloc_name(fsi->policycap_dir, "unknown");
1887
1888                 if (dentry == NULL)
1889                         return -ENOMEM;
1890
1891                 inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
1892                 if (inode == NULL) {
1893                         dput(dentry);
1894                         return -ENOMEM;
1895                 }
1896
1897                 inode->i_fop = &sel_policycap_ops;
1898                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1899                 d_add(dentry, inode);
1900         }
1901
1902         return 0;
1903 }
1904
1905 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1906                         unsigned long *ino)
1907 {
1908         struct dentry *dentry = d_alloc_name(dir, name);
1909         struct inode *inode;
1910
1911         if (!dentry)
1912                 return ERR_PTR(-ENOMEM);
1913
1914         inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1915         if (!inode) {
1916                 dput(dentry);
1917                 return ERR_PTR(-ENOMEM);
1918         }
1919
1920         inode->i_op = &simple_dir_inode_operations;
1921         inode->i_fop = &simple_dir_operations;
1922         inode->i_ino = ++(*ino);
1923         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1924         inc_nlink(inode);
1925         d_add(dentry, inode);
1926         /* bump link count on parent directory, too */
1927         inc_nlink(d_inode(dir));
1928
1929         return dentry;
1930 }
1931
1932 static int reject_all(struct mnt_idmap *idmap, struct inode *inode, int mask)
1933 {
1934         return -EPERM;  // no access for anyone, root or no root.
1935 }
1936
1937 static const struct inode_operations swapover_dir_inode_operations = {
1938         .lookup         = simple_lookup,
1939         .permission     = reject_all,
1940 };
1941
1942 static struct dentry *sel_make_swapover_dir(struct super_block *sb,
1943                                                 unsigned long *ino)
1944 {
1945         struct dentry *dentry = d_alloc_name(sb->s_root, ".swapover");
1946         struct inode *inode;
1947
1948         if (!dentry)
1949                 return ERR_PTR(-ENOMEM);
1950
1951         inode = sel_make_inode(sb, S_IFDIR);
1952         if (!inode) {
1953                 dput(dentry);
1954                 return ERR_PTR(-ENOMEM);
1955         }
1956
1957         inode->i_op = &swapover_dir_inode_operations;
1958         inode->i_ino = ++(*ino);
1959         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1960         inc_nlink(inode);
1961         inode_lock(sb->s_root->d_inode);
1962         d_add(dentry, inode);
1963         inc_nlink(sb->s_root->d_inode);
1964         inode_unlock(sb->s_root->d_inode);
1965         return dentry;
1966 }
1967
1968 #define NULL_FILE_NAME "null"
1969
1970 static int sel_fill_super(struct super_block *sb, struct fs_context *fc)
1971 {
1972         struct selinux_fs_info *fsi;
1973         int ret;
1974         struct dentry *dentry;
1975         struct inode *inode;
1976         struct inode_security_struct *isec;
1977
1978         static const struct tree_descr selinux_files[] = {
1979                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1980                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1981                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1982                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1983                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1984                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1985                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1986                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1987                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1988                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1989                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1990                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1991                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1992                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1993                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1994                 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1995                 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
1996                 [SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
1997                                         S_IWUGO},
1998                 /* last one */ {""}
1999         };
2000
2001         ret = selinux_fs_info_create(sb);
2002         if (ret)
2003                 goto err;
2004
2005         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
2006         if (ret)
2007                 goto err;
2008
2009         fsi = sb->s_fs_info;
2010         fsi->bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &fsi->last_ino);
2011         if (IS_ERR(fsi->bool_dir)) {
2012                 ret = PTR_ERR(fsi->bool_dir);
2013                 fsi->bool_dir = NULL;
2014                 goto err;
2015         }
2016
2017         ret = -ENOMEM;
2018         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
2019         if (!dentry)
2020                 goto err;
2021
2022         ret = -ENOMEM;
2023         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
2024         if (!inode) {
2025                 dput(dentry);
2026                 goto err;
2027         }
2028
2029         inode->i_ino = ++fsi->last_ino;
2030         isec = selinux_inode(inode);
2031         isec->sid = SECINITSID_DEVNULL;
2032         isec->sclass = SECCLASS_CHR_FILE;
2033         isec->initialized = LABEL_INITIALIZED;
2034
2035         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
2036         d_add(dentry, inode);
2037
2038         dentry = sel_make_dir(sb->s_root, "avc", &fsi->last_ino);
2039         if (IS_ERR(dentry)) {
2040                 ret = PTR_ERR(dentry);
2041                 goto err;
2042         }
2043
2044         ret = sel_make_avc_files(dentry);
2045         if (ret)
2046                 goto err;
2047
2048         dentry = sel_make_dir(sb->s_root, "ss", &fsi->last_ino);
2049         if (IS_ERR(dentry)) {
2050                 ret = PTR_ERR(dentry);
2051                 goto err;
2052         }
2053
2054         ret = sel_make_ss_files(dentry);
2055         if (ret)
2056                 goto err;
2057
2058         dentry = sel_make_dir(sb->s_root, "initial_contexts", &fsi->last_ino);
2059         if (IS_ERR(dentry)) {
2060                 ret = PTR_ERR(dentry);
2061                 goto err;
2062         }
2063
2064         ret = sel_make_initcon_files(dentry);
2065         if (ret)
2066                 goto err;
2067
2068         fsi->class_dir = sel_make_dir(sb->s_root, CLASS_DIR_NAME, &fsi->last_ino);
2069         if (IS_ERR(fsi->class_dir)) {
2070                 ret = PTR_ERR(fsi->class_dir);
2071                 fsi->class_dir = NULL;
2072                 goto err;
2073         }
2074
2075         fsi->policycap_dir = sel_make_dir(sb->s_root, POLICYCAP_DIR_NAME,
2076                                           &fsi->last_ino);
2077         if (IS_ERR(fsi->policycap_dir)) {
2078                 ret = PTR_ERR(fsi->policycap_dir);
2079                 fsi->policycap_dir = NULL;
2080                 goto err;
2081         }
2082
2083         ret = sel_make_policycap(fsi);
2084         if (ret) {
2085                 pr_err("SELinux: failed to load policy capabilities\n");
2086                 goto err;
2087         }
2088
2089         return 0;
2090 err:
2091         pr_err("SELinux: %s:  failed while creating inodes\n",
2092                 __func__);
2093
2094         selinux_fs_info_free(sb);
2095
2096         return ret;
2097 }
2098
2099 static int sel_get_tree(struct fs_context *fc)
2100 {
2101         return get_tree_single(fc, sel_fill_super);
2102 }
2103
2104 static const struct fs_context_operations sel_context_ops = {
2105         .get_tree       = sel_get_tree,
2106 };
2107
2108 static int sel_init_fs_context(struct fs_context *fc)
2109 {
2110         fc->ops = &sel_context_ops;
2111         return 0;
2112 }
2113
2114 static void sel_kill_sb(struct super_block *sb)
2115 {
2116         selinux_fs_info_free(sb);
2117         kill_litter_super(sb);
2118 }
2119
2120 static struct file_system_type sel_fs_type = {
2121         .name           = "selinuxfs",
2122         .init_fs_context = sel_init_fs_context,
2123         .kill_sb        = sel_kill_sb,
2124 };
2125
2126 static struct vfsmount *selinuxfs_mount __ro_after_init;
2127 struct path selinux_null __ro_after_init;
2128
2129 static int __init init_sel_fs(void)
2130 {
2131         struct qstr null_name = QSTR_INIT(NULL_FILE_NAME,
2132                                           sizeof(NULL_FILE_NAME)-1);
2133         int err;
2134
2135         if (!selinux_enabled_boot)
2136                 return 0;
2137
2138         err = sysfs_create_mount_point(fs_kobj, "selinux");
2139         if (err)
2140                 return err;
2141
2142         err = register_filesystem(&sel_fs_type);
2143         if (err) {
2144                 sysfs_remove_mount_point(fs_kobj, "selinux");
2145                 return err;
2146         }
2147
2148         selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type);
2149         if (IS_ERR(selinuxfs_mount)) {
2150                 pr_err("selinuxfs:  could not mount!\n");
2151                 err = PTR_ERR(selinuxfs_mount);
2152                 selinuxfs_mount = NULL;
2153         }
2154         selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root,
2155                                                 &null_name);
2156         if (IS_ERR(selinux_null.dentry)) {
2157                 pr_err("selinuxfs:  could not lookup null!\n");
2158                 err = PTR_ERR(selinux_null.dentry);
2159                 selinux_null.dentry = NULL;
2160         }
2161
2162         return err;
2163 }
2164
2165 __initcall(init_sel_fs);