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/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
  46enum 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
  70struct 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
  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	fsi->last_ino = SEL_INO_NEXT - 1;
  92	fsi->sb = sb;
  93	sb->s_fs_info = fsi;
  94	return 0;
  95}
  96
  97static 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
 123static 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
 135static 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;
 185out:
 186	kfree(page);
 187	return length;
 188}
 189#else
 190#define sel_write_enforce NULL
 191#endif
 192
 193static const struct file_operations sel_enforce_ops = {
 194	.read		= sel_read_enforce,
 195	.write		= sel_write_enforce,
 196	.llseek		= generic_file_llseek,
 197};
 198
 199static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
 200					size_t count, loff_t *ppos)
 201{
 202	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
 213static const struct file_operations sel_handle_unknown_ops = {
 214	.read		= sel_read_handle_unknown,
 215	.llseek		= generic_file_llseek,
 216};
 217
 218static 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
 230static 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
 242static 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
 264static 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
 
 271static 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
 
 301out:
 302	kfree(page);
 303	return length;
 304}
 
 
 
 305
 306static const struct file_operations sel_disable_ops = {
 307	.write		= sel_write_disable,
 308	.llseek		= generic_file_llseek,
 309};
 310
 311static 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
 321static 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 */
 327static 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);
 330static 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 */
 335static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
 336			unsigned long *ino);
 337
 338/* declaration for sel_make_policy_nodes */
 339static struct dentry *sel_make_swapover_dir(struct super_block *sb,
 340						unsigned long *ino);
 341
 342static 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
 353static const struct file_operations sel_mls_ops = {
 354	.read		= sel_read_mls,
 355	.llseek		= generic_file_llseek,
 356};
 357
 358struct policy_load_memory {
 359	size_t len;
 360	void *data;
 361};
 362
 363static 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;
 404err:
 405	mutex_unlock(&selinux_state.policy_mutex);
 406
 407	if (plm)
 408		vfree(plm->data);
 409	kfree(plm);
 410	return rc;
 411}
 412
 413static 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
 428static 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
 442static 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
 463static const struct vm_operations_struct sel_mmap_policy_ops = {
 464	.fault = sel_mmap_policy_fault,
 465	.page_mkwrite = sel_mmap_policy_fault,
 466};
 467
 468static 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
 484static 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
 492static 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
 504static 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
 559out:
 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
 570static 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));
 621out:
 622	mutex_unlock(&selinux_state.policy_mutex);
 623	vfree(data);
 624	return length;
 625}
 626
 627static const struct file_operations sel_load_ops = {
 628	.write		= sel_write_load,
 629	.llseek		= generic_file_llseek,
 630};
 631
 632static 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;
 660out:
 661	kfree(canon);
 662	return length;
 663}
 664
 665static 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
 676static 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
 
 
 716out:
 717	kfree(page);
 718	return length;
 719}
 720static const struct file_operations sel_checkreqprot_ops = {
 721	.read		= sel_read_checkreqprot,
 722	.write		= sel_write_checkreqprot,
 723	.llseek		= generic_file_llseek,
 724};
 725
 726static 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;
 789out:
 790	kfree(req);
 791	kfree(oldcon);
 792	kfree(newcon);
 793	kfree(taskcon);
 794	return rc;
 795}
 796
 797static 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 */
 805static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
 806static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
 807static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
 808static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
 809static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
 810
 811static 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
 820static 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
 841static 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
 854static 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);
 896out:
 897	kfree(tcon);
 898	kfree(scon);
 899	return length;
 900}
 901
 902static 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;
 995out:
 996	kfree(newcon);
 997	kfree(namebuf);
 998	kfree(tcon);
 999	kfree(scon);
1000	return length;
1001}
1002
1003static 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;
1054out:
1055	kfree(newcon);
1056	kfree(tcon);
1057	kfree(scon);
1058	return length;
1059}
1060
1061static 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	}
1116out:
1117	kfree(sids);
1118	kfree(user);
1119	kfree(con);
1120	return length;
1121}
1122
1123static 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;
1177out:
1178	kfree(newcon);
1179	kfree(tcon);
1180	kfree(scon);
1181	return length;
1182}
1183
1184static 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
1195static 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);
1227out_free:
 
1228	free_page((unsigned long)page);
1229	return ret;
1230
1231out_unlock:
1232	mutex_unlock(&selinux_state.policy_mutex);
1233	goto out_free;
1234}
1235
1236static 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
1280out:
1281	mutex_unlock(&selinux_state.policy_mutex);
1282	kfree(page);
1283	return length;
1284}
1285
1286static const struct file_operations sel_bool_ops = {
1287	.read		= sel_read_bool,
1288	.write		= sel_write_bool,
1289	.llseek		= generic_file_llseek,
1290};
1291
1292static 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
1332out:
1333	mutex_unlock(&selinux_state.policy_mutex);
1334	kfree(page);
1335	return length;
1336}
1337
1338static const struct file_operations sel_commit_bools_ops = {
1339	.write		= sel_commit_bools_write,
1340	.llseek		= generic_file_llseek,
1341};
1342
1343static 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	}
 
 
 
 
 
 
1402out:
1403	free_page((unsigned long)page);
 
 
 
 
 
 
 
 
 
1404	return ret;
1405}
1406
 
 
 
 
1407static 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
1418static 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;
1451out:
1452	kfree(page);
1453	return ret;
1454}
1455
1456static 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
1474static 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
1493static const struct file_operations sel_sidtab_hash_stats_ops = {
1494	.read		= sel_read_sidtab_hash_stats,
1495	.llseek		= generic_file_llseek,
1496};
1497
1498static 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
1504static 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
1510static 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
1524static 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
1534static 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
1539static 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
1557static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1558{ }
1559
1560static 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
1567static 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
1572static 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
1580static 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
1616static 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
1647static 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
1664static const struct file_operations sel_initcon_ops = {
1665	.read		= sel_read_initcon,
1666	.llseek		= generic_file_llseek,
1667};
1668
1669static 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
1698static inline unsigned long sel_class_to_ino(u16 class)
1699{
1700	return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1701}
1702
1703static inline u16 sel_ino_to_class(unsigned long ino)
1704{
1705	return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1706}
1707
1708static 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
1713static inline u32 sel_ino_to_perm(unsigned long ino)
1714{
1715	return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1716}
1717
1718static 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
1727static const struct file_operations sel_class_ops = {
1728	.read		= sel_read_class,
1729	.llseek		= generic_file_llseek,
1730};
1731
1732static 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
1741static const struct file_operations sel_perm_ops = {
1742	.read		= sel_read_perm,
1743	.llseek		= generic_file_llseek,
1744};
1745
1746static 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
1760static const struct file_operations sel_policycap_ops = {
1761	.read		= sel_read_policycap,
1762	.llseek		= generic_file_llseek,
1763};
1764
1765static 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;
1799out:
1800	for (i = 0; i < nperms; i++)
1801		kfree(perms[i]);
1802	kfree(perms);
1803	return rc;
1804}
1805
1806static 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
1836static 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;
1868out:
1869	for (i = 0; i < nclasses; i++)
1870		kfree(classes[i]);
1871	kfree(classes);
1872	return rc;
1873}
1874
1875static 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
1905static 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
1932static 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
1937static const struct inode_operations swapover_dir_inode_operations = {
1938	.lookup		= simple_lookup,
1939	.permission	= reject_all,
1940};
1941
1942static 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
1970static 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;
2090err:
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
2099static int sel_get_tree(struct fs_context *fc)
 
2100{
2101	return get_tree_single(fc, sel_fill_super);
2102}
2103
2104static const struct fs_context_operations sel_context_ops = {
2105	.get_tree	= sel_get_tree,
2106};
2107
2108static int sel_init_fs_context(struct fs_context *fc)
2109{
2110	fc->ops = &sel_context_ops;
2111	return 0;
2112}
2113
2114static void sel_kill_sb(struct super_block *sb)
2115{
2116	selinux_fs_info_free(sb);
2117	kill_litter_super(sb);
2118}
2119
2120static 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
2126static struct vfsmount *selinuxfs_mount __ro_after_init;
2127struct path selinux_null __ro_after_init;
2128
2129static 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);