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(objp: fsi->bool_pending_names[i]);
105 kfree(objp: fsi->bool_pending_names);
106 kfree(objp: fsi->bool_pending_values);
107 }
108 kfree(objp: 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(buf: tmpbuf, TMPBUFLEN, fmt: "%d",
130 enforcing_enabled());
131 return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: 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(ptr: page))
153 return PTR_ERR(ptr: 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(ssid: current_sid(), SECINITSID_SECURITY,
164 SECCLASS_SECURITY, SECURITY__SETENFORCE,
165 NULL);
166 if (length)
167 goto out;
168 audit_log(ctx: audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
169 fmt: "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(to: &init_user_ns, kuid: audit_get_loginuid(current)),
173 audit_get_sessionid(current));
174 enforcing_set(value: new_value);
175 if (new_value)
176 avc_ss_reset(seqno: 0);
177 selnl_notify_setenforce(val: new_value);
178 selinux_status_update_setenforce(enforcing: new_value);
179 if (!new_value)
180 call_blocking_lsm_notifier(event: LSM_POLICY_CHANGE, NULL);
181
182 selinux_ima_measure_state();
183 }
184 length = count;
185out:
186 kfree(objp: 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(f: 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(buf: tmpbuf, TMPBUFLEN, fmt: "%d", handle_unknown);
210 return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: 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(to: buf, count, ppos,
238 page_address(status),
239 available: 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, addr: 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(ptr: page))
288 return PTR_ERR(ptr: 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(objp: 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(buf: tmpbuf, TMPBUFLEN, fmt: "%u", POLICYDB_VERSION_MAX);
318 return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: 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(buf: tmpbuf, TMPBUFLEN, fmt: "%d",
349 security_mls_enabled());
350 return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: 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(lock: &selinux_state.policy_mutex);
372
373 rc = avc_has_perm(ssid: 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(data: &plm->data, len: &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, i_size: plm->len);
394 inode_unlock(inode);
395 }
396
397 fsi->policy_opened = 1;
398
399 filp->private_data = plm;
400
401 mutex_unlock(lock: &selinux_state.policy_mutex);
402
403 return 0;
404err:
405 mutex_unlock(lock: &selinux_state.policy_mutex);
406
407 if (plm)
408 vfree(addr: plm->data);
409 kfree(objp: 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(addr: plm->data);
423 kfree(objp: 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(ssid: current_sid(), SECINITSID_SECURITY,
435 SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
436 if (ret)
437 return ret;
438
439 return simple_read_from_buffer(to: buf, count, ppos, from: plm->data, available: 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(addr: 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(objp: bool_names[i]);
500 kfree(objp: bool_names);
501 kfree(objp: 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(sb: fsi->sb, ino: &tmp_ino);
515 if (IS_ERR(ptr: tmp_parent))
516 return PTR_ERR(ptr: 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(dir: tmp_parent, BOOL_DIR_NAME, ino: &tmp_ino);
520 if (IS_ERR(ptr: tmp_bool_dir)) {
521 ret = PTR_ERR(ptr: 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(dir: tmp_parent, CLASS_DIR_NAME, ino: &tmp_ino);
527 if (IS_ERR(ptr: tmp_class_dir)) {
528 ret = PTR_ERR(ptr: tmp_class_dir);
529 goto out;
530 }
531
532 ret = sel_make_bools(newpolicy, bool_dir: tmp_bool_dir, bool_num: &bool_num,
533 bool_pending_names: &bool_names, bool_pending_values: &bool_values);
534 if (ret)
535 goto out;
536
537 ret = sel_make_classes(newpolicy, class_dir: tmp_class_dir,
538 last_class_ino: &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;
575 struct selinux_load_state load_state;
576 ssize_t length;
577 void *data = NULL;
578
579 /* no partial writes */
580 if (*ppos)
581 return -EINVAL;
582 /* no empty policies */
583 if (!count)
584 return -EINVAL;
585
586 mutex_lock(lock: &selinux_state.policy_mutex);
587
588 length = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
589 SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
590 if (length)
591 goto out;
592
593 data = vmalloc(count);
594 if (!data) {
595 length = -ENOMEM;
596 goto out;
597 }
598 if (copy_from_user(to: data, from: buf, n: count) != 0) {
599 length = -EFAULT;
600 goto out;
601 }
602
603 length = security_load_policy(data, len: count, load_state: &load_state);
604 if (length) {
605 pr_warn_ratelimited("SELinux: failed to load policy\n");
606 goto out;
607 }
608 fsi = file_inode(f: file)->i_sb->s_fs_info;
609 length = sel_make_policy_nodes(fsi, newpolicy: load_state.policy);
610 if (length) {
611 pr_warn_ratelimited("SELinux: failed to initialize selinuxfs\n");
612 selinux_policy_cancel(load_state: &load_state);
613 goto out;
614 }
615
616 selinux_policy_commit(load_state: &load_state);
617 length = count;
618 audit_log(ctx: audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
619 fmt: "auid=%u ses=%u lsm=selinux res=1",
620 from_kuid(to: &init_user_ns, kuid: audit_get_loginuid(current)),
621 audit_get_sessionid(current));
622
623out:
624 mutex_unlock(lock: &selinux_state.policy_mutex);
625 vfree(addr: data);
626 return length;
627}
628
629static const struct file_operations sel_load_ops = {
630 .write = sel_write_load,
631 .llseek = generic_file_llseek,
632};
633
634static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
635{
636 char *canon = NULL;
637 u32 sid, len;
638 ssize_t length;
639
640 length = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
641 SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
642 if (length)
643 goto out;
644
645 length = security_context_to_sid(scontext: buf, scontext_len: size, out_sid: &sid, GFP_KERNEL);
646 if (length)
647 goto out;
648
649 length = security_sid_to_context(sid, scontext: &canon, scontext_len: &len);
650 if (length)
651 goto out;
652
653 length = -ERANGE;
654 if (len > SIMPLE_TRANSACTION_LIMIT) {
655 pr_err("SELinux: %s: context size (%u) exceeds "
656 "payload max\n", __func__, len);
657 goto out;
658 }
659
660 memcpy(to: buf, from: canon, len);
661 length = len;
662out:
663 kfree(objp: canon);
664 return length;
665}
666
667static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
668 size_t count, loff_t *ppos)
669{
670 char tmpbuf[TMPBUFLEN];
671 ssize_t length;
672
673 length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%u",
674 checkreqprot_get());
675 return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length);
676}
677
678static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
679 size_t count, loff_t *ppos)
680{
681 char *page;
682 ssize_t length;
683 unsigned int new_value;
684
685 length = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
686 SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
687 NULL);
688 if (length)
689 return length;
690
691 if (count >= PAGE_SIZE)
692 return -ENOMEM;
693
694 /* No partial writes. */
695 if (*ppos != 0)
696 return -EINVAL;
697
698 page = memdup_user_nul(buf, count);
699 if (IS_ERR(ptr: page))
700 return PTR_ERR(ptr: page);
701
702 if (sscanf(page, "%u", &new_value) != 1) {
703 length = -EINVAL;
704 goto out;
705 }
706 length = count;
707
708 if (new_value) {
709 char comm[sizeof(current->comm)];
710
711 strscpy(comm, current->comm);
712 pr_err("SELinux: %s (%d) set checkreqprot to 1. This is no longer supported.\n",
713 comm, current->pid);
714 }
715
716 selinux_ima_measure_state();
717
718out:
719 kfree(objp: page);
720 return length;
721}
722static const struct file_operations sel_checkreqprot_ops = {
723 .read = sel_read_checkreqprot,
724 .write = sel_write_checkreqprot,
725 .llseek = generic_file_llseek,
726};
727
728static ssize_t sel_write_validatetrans(struct file *file,
729 const char __user *buf,
730 size_t count, loff_t *ppos)
731{
732 char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
733 char *req = NULL;
734 u32 osid, nsid, tsid;
735 u16 tclass;
736 int rc;
737
738 rc = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
739 SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
740 if (rc)
741 goto out;
742
743 rc = -ENOMEM;
744 if (count >= PAGE_SIZE)
745 goto out;
746
747 /* No partial writes. */
748 rc = -EINVAL;
749 if (*ppos != 0)
750 goto out;
751
752 req = memdup_user_nul(buf, count);
753 if (IS_ERR(ptr: req)) {
754 rc = PTR_ERR(ptr: req);
755 req = NULL;
756 goto out;
757 }
758
759 rc = -ENOMEM;
760 oldcon = kzalloc(count + 1, GFP_KERNEL);
761 if (!oldcon)
762 goto out;
763
764 newcon = kzalloc(count + 1, GFP_KERNEL);
765 if (!newcon)
766 goto out;
767
768 taskcon = kzalloc(count + 1, GFP_KERNEL);
769 if (!taskcon)
770 goto out;
771
772 rc = -EINVAL;
773 if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
774 goto out;
775
776 rc = security_context_str_to_sid(scontext: oldcon, out_sid: &osid, GFP_KERNEL);
777 if (rc)
778 goto out;
779
780 rc = security_context_str_to_sid(scontext: newcon, out_sid: &nsid, GFP_KERNEL);
781 if (rc)
782 goto out;
783
784 rc = security_context_str_to_sid(scontext: taskcon, out_sid: &tsid, GFP_KERNEL);
785 if (rc)
786 goto out;
787
788 rc = security_validate_transition_user(oldsid: osid, newsid: nsid, tasksid: tsid, tclass);
789 if (!rc)
790 rc = count;
791out:
792 kfree(objp: req);
793 kfree(objp: oldcon);
794 kfree(objp: newcon);
795 kfree(objp: taskcon);
796 return rc;
797}
798
799static const struct file_operations sel_transition_ops = {
800 .write = sel_write_validatetrans,
801 .llseek = generic_file_llseek,
802};
803
804/*
805 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
806 */
807static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
808static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
809static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
810static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
811static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
812
813static ssize_t (*const write_op[])(struct file *, char *, size_t) = {
814 [SEL_ACCESS] = sel_write_access,
815 [SEL_CREATE] = sel_write_create,
816 [SEL_RELABEL] = sel_write_relabel,
817 [SEL_USER] = sel_write_user,
818 [SEL_MEMBER] = sel_write_member,
819 [SEL_CONTEXT] = sel_write_context,
820};
821
822static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
823{
824 ino_t ino = file_inode(f: file)->i_ino;
825 char *data;
826 ssize_t rv;
827
828 if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
829 return -EINVAL;
830
831 data = simple_transaction_get(file, buf, size);
832 if (IS_ERR(ptr: data))
833 return PTR_ERR(ptr: data);
834
835 rv = write_op[ino](file, data, size);
836 if (rv > 0) {
837 simple_transaction_set(file, n: rv);
838 rv = size;
839 }
840 return rv;
841}
842
843static const struct file_operations transaction_ops = {
844 .write = selinux_transaction_write,
845 .read = simple_transaction_read,
846 .release = simple_transaction_release,
847 .llseek = generic_file_llseek,
848};
849
850/*
851 * payload - write methods
852 * If the method has a response, the response should be put in buf,
853 * and the length returned. Otherwise return 0 or and -error.
854 */
855
856static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
857{
858 char *scon = NULL, *tcon = NULL;
859 u32 ssid, tsid;
860 u16 tclass;
861 struct av_decision avd;
862 ssize_t length;
863
864 length = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
865 SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
866 if (length)
867 goto out;
868
869 length = -ENOMEM;
870 scon = kzalloc(size + 1, GFP_KERNEL);
871 if (!scon)
872 goto out;
873
874 length = -ENOMEM;
875 tcon = kzalloc(size + 1, GFP_KERNEL);
876 if (!tcon)
877 goto out;
878
879 length = -EINVAL;
880 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
881 goto out;
882
883 length = security_context_str_to_sid(scontext: scon, out_sid: &ssid, GFP_KERNEL);
884 if (length)
885 goto out;
886
887 length = security_context_str_to_sid(scontext: tcon, out_sid: &tsid, GFP_KERNEL);
888 if (length)
889 goto out;
890
891 security_compute_av_user(ssid, tsid, tclass, avd: &avd);
892
893 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
894 fmt: "%x %x %x %x %u %x",
895 avd.allowed, 0xffffffff,
896 avd.auditallow, avd.auditdeny,
897 avd.seqno, avd.flags);
898out:
899 kfree(objp: tcon);
900 kfree(objp: scon);
901 return length;
902}
903
904static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
905{
906 char *scon = NULL, *tcon = NULL;
907 char *namebuf = NULL, *objname = NULL;
908 u32 ssid, tsid, newsid;
909 u16 tclass;
910 ssize_t length;
911 char *newcon = NULL;
912 u32 len;
913 int nargs;
914
915 length = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
916 SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
917 NULL);
918 if (length)
919 goto out;
920
921 length = -ENOMEM;
922 scon = kzalloc(size + 1, GFP_KERNEL);
923 if (!scon)
924 goto out;
925
926 length = -ENOMEM;
927 tcon = kzalloc(size + 1, GFP_KERNEL);
928 if (!tcon)
929 goto out;
930
931 length = -ENOMEM;
932 namebuf = kzalloc(size + 1, GFP_KERNEL);
933 if (!namebuf)
934 goto out;
935
936 length = -EINVAL;
937 nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
938 if (nargs < 3 || nargs > 4)
939 goto out;
940 if (nargs == 4) {
941 /*
942 * If and when the name of new object to be queried contains
943 * either whitespace or multibyte characters, they shall be
944 * encoded based on the percentage-encoding rule.
945 * If not encoded, the sscanf logic picks up only left-half
946 * of the supplied name; split by a whitespace unexpectedly.
947 */
948 char *r, *w;
949 int c1, c2;
950
951 r = w = namebuf;
952 do {
953 c1 = *r++;
954 if (c1 == '+')
955 c1 = ' ';
956 else if (c1 == '%') {
957 c1 = hex_to_bin(ch: *r++);
958 if (c1 < 0)
959 goto out;
960 c2 = hex_to_bin(ch: *r++);
961 if (c2 < 0)
962 goto out;
963 c1 = (c1 << 4) | c2;
964 }
965 *w++ = c1;
966 } while (c1 != '\0');
967
968 objname = namebuf;
969 }
970
971 length = security_context_str_to_sid(scontext: scon, out_sid: &ssid, GFP_KERNEL);
972 if (length)
973 goto out;
974
975 length = security_context_str_to_sid(scontext: tcon, out_sid: &tsid, GFP_KERNEL);
976 if (length)
977 goto out;
978
979 length = security_transition_sid_user(ssid, tsid, tclass,
980 objname, out_sid: &newsid);
981 if (length)
982 goto out;
983
984 length = security_sid_to_context(sid: newsid, scontext: &newcon, scontext_len: &len);
985 if (length)
986 goto out;
987
988 length = -ERANGE;
989 if (len > SIMPLE_TRANSACTION_LIMIT) {
990 pr_err("SELinux: %s: context size (%u) exceeds "
991 "payload max\n", __func__, len);
992 goto out;
993 }
994
995 memcpy(to: buf, from: newcon, len);
996 length = len;
997out:
998 kfree(objp: newcon);
999 kfree(objp: namebuf);
1000 kfree(objp: tcon);
1001 kfree(objp: scon);
1002 return length;
1003}
1004
1005static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
1006{
1007 char *scon = NULL, *tcon = NULL;
1008 u32 ssid, tsid, newsid;
1009 u16 tclass;
1010 ssize_t length;
1011 char *newcon = NULL;
1012 u32 len;
1013
1014 length = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
1015 SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
1016 NULL);
1017 if (length)
1018 goto out;
1019
1020 length = -ENOMEM;
1021 scon = kzalloc(size + 1, GFP_KERNEL);
1022 if (!scon)
1023 goto out;
1024
1025 length = -ENOMEM;
1026 tcon = kzalloc(size + 1, GFP_KERNEL);
1027 if (!tcon)
1028 goto out;
1029
1030 length = -EINVAL;
1031 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1032 goto out;
1033
1034 length = security_context_str_to_sid(scontext: scon, out_sid: &ssid, GFP_KERNEL);
1035 if (length)
1036 goto out;
1037
1038 length = security_context_str_to_sid(scontext: tcon, out_sid: &tsid, GFP_KERNEL);
1039 if (length)
1040 goto out;
1041
1042 length = security_change_sid(ssid, tsid, tclass, out_sid: &newsid);
1043 if (length)
1044 goto out;
1045
1046 length = security_sid_to_context(sid: newsid, scontext: &newcon, scontext_len: &len);
1047 if (length)
1048 goto out;
1049
1050 length = -ERANGE;
1051 if (len > SIMPLE_TRANSACTION_LIMIT)
1052 goto out;
1053
1054 memcpy(to: buf, from: newcon, len);
1055 length = len;
1056out:
1057 kfree(objp: newcon);
1058 kfree(objp: tcon);
1059 kfree(objp: scon);
1060 return length;
1061}
1062
1063static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
1064{
1065 char *con = NULL, *user = NULL, *ptr;
1066 u32 sid, *sids = NULL;
1067 ssize_t length;
1068 char *newcon;
1069 int rc;
1070 u32 i, len, nsids;
1071
1072 pr_warn_ratelimited("SELinux: %s (%d) wrote to /sys/fs/selinux/user!"
1073 " This will not be supported in the future; please update your"
1074 " userspace.\n", current->comm, current->pid);
1075 ssleep(seconds: 5);
1076
1077 length = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
1078 SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
1079 NULL);
1080 if (length)
1081 goto out;
1082
1083 length = -ENOMEM;
1084 con = kzalloc(size + 1, GFP_KERNEL);
1085 if (!con)
1086 goto out;
1087
1088 length = -ENOMEM;
1089 user = kzalloc(size + 1, GFP_KERNEL);
1090 if (!user)
1091 goto out;
1092
1093 length = -EINVAL;
1094 if (sscanf(buf, "%s %s", con, user) != 2)
1095 goto out;
1096
1097 length = security_context_str_to_sid(scontext: con, out_sid: &sid, GFP_KERNEL);
1098 if (length)
1099 goto out;
1100
1101 length = security_get_user_sids(fromsid: sid, username: user, sids: &sids, nel: &nsids);
1102 if (length)
1103 goto out;
1104
1105 length = sprintf(buf, fmt: "%u", nsids) + 1;
1106 ptr = buf + length;
1107 for (i = 0; i < nsids; i++) {
1108 rc = security_sid_to_context(sid: sids[i], scontext: &newcon, scontext_len: &len);
1109 if (rc) {
1110 length = rc;
1111 goto out;
1112 }
1113 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1114 kfree(objp: newcon);
1115 length = -ERANGE;
1116 goto out;
1117 }
1118 memcpy(to: ptr, from: newcon, len);
1119 kfree(objp: newcon);
1120 ptr += len;
1121 length += len;
1122 }
1123out:
1124 kfree(objp: sids);
1125 kfree(objp: user);
1126 kfree(objp: con);
1127 return length;
1128}
1129
1130static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1131{
1132 char *scon = NULL, *tcon = NULL;
1133 u32 ssid, tsid, newsid;
1134 u16 tclass;
1135 ssize_t length;
1136 char *newcon = NULL;
1137 u32 len;
1138
1139 length = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
1140 SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
1141 NULL);
1142 if (length)
1143 goto out;
1144
1145 length = -ENOMEM;
1146 scon = kzalloc(size + 1, GFP_KERNEL);
1147 if (!scon)
1148 goto out;
1149
1150 length = -ENOMEM;
1151 tcon = kzalloc(size + 1, GFP_KERNEL);
1152 if (!tcon)
1153 goto out;
1154
1155 length = -EINVAL;
1156 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1157 goto out;
1158
1159 length = security_context_str_to_sid(scontext: scon, out_sid: &ssid, GFP_KERNEL);
1160 if (length)
1161 goto out;
1162
1163 length = security_context_str_to_sid(scontext: tcon, out_sid: &tsid, GFP_KERNEL);
1164 if (length)
1165 goto out;
1166
1167 length = security_member_sid(ssid, tsid, tclass, out_sid: &newsid);
1168 if (length)
1169 goto out;
1170
1171 length = security_sid_to_context(sid: newsid, scontext: &newcon, scontext_len: &len);
1172 if (length)
1173 goto out;
1174
1175 length = -ERANGE;
1176 if (len > SIMPLE_TRANSACTION_LIMIT) {
1177 pr_err("SELinux: %s: context size (%u) exceeds "
1178 "payload max\n", __func__, len);
1179 goto out;
1180 }
1181
1182 memcpy(to: buf, from: newcon, len);
1183 length = len;
1184out:
1185 kfree(objp: newcon);
1186 kfree(objp: tcon);
1187 kfree(objp: scon);
1188 return length;
1189}
1190
1191static struct inode *sel_make_inode(struct super_block *sb, umode_t mode)
1192{
1193 struct inode *ret = new_inode(sb);
1194
1195 if (ret) {
1196 ret->i_mode = mode;
1197 simple_inode_init_ts(inode: ret);
1198 }
1199 return ret;
1200}
1201
1202static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1203 size_t count, loff_t *ppos)
1204{
1205 struct selinux_fs_info *fsi = file_inode(f: filep)->i_sb->s_fs_info;
1206 char buffer[4];
1207 ssize_t length;
1208 ssize_t ret;
1209 int cur_enforcing;
1210 unsigned index = file_inode(f: filep)->i_ino & SEL_INO_MASK;
1211 const char *name = filep->f_path.dentry->d_name.name;
1212
1213 mutex_lock(lock: &selinux_state.policy_mutex);
1214
1215 ret = -EINVAL;
1216 if (index >= fsi->bool_num || strcmp(name,
1217 fsi->bool_pending_names[index]))
1218 goto out_unlock;
1219
1220 cur_enforcing = security_get_bool_value(index);
1221 if (cur_enforcing < 0) {
1222 ret = cur_enforcing;
1223 goto out_unlock;
1224 }
1225 length = scnprintf(buf: buffer, size: sizeof(buffer), fmt: "%d %d", !!cur_enforcing,
1226 !!fsi->bool_pending_values[index]);
1227 mutex_unlock(lock: &selinux_state.policy_mutex);
1228 return simple_read_from_buffer(to: buf, count, ppos, from: buffer, available: length);
1229
1230out_unlock:
1231 mutex_unlock(lock: &selinux_state.policy_mutex);
1232 return ret;
1233}
1234
1235static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1236 size_t count, loff_t *ppos)
1237{
1238 struct selinux_fs_info *fsi = file_inode(f: filep)->i_sb->s_fs_info;
1239 char *page = NULL;
1240 ssize_t length;
1241 int new_value;
1242 unsigned index = file_inode(f: filep)->i_ino & SEL_INO_MASK;
1243 const char *name = filep->f_path.dentry->d_name.name;
1244
1245 if (count >= PAGE_SIZE)
1246 return -ENOMEM;
1247
1248 /* No partial writes. */
1249 if (*ppos != 0)
1250 return -EINVAL;
1251
1252 page = memdup_user_nul(buf, count);
1253 if (IS_ERR(ptr: page))
1254 return PTR_ERR(ptr: page);
1255
1256 mutex_lock(lock: &selinux_state.policy_mutex);
1257
1258 length = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
1259 SECCLASS_SECURITY, SECURITY__SETBOOL,
1260 NULL);
1261 if (length)
1262 goto out;
1263
1264 length = -EINVAL;
1265 if (index >= fsi->bool_num || strcmp(name,
1266 fsi->bool_pending_names[index]))
1267 goto out;
1268
1269 length = -EINVAL;
1270 if (sscanf(page, "%d", &new_value) != 1)
1271 goto out;
1272
1273 if (new_value)
1274 new_value = 1;
1275
1276 fsi->bool_pending_values[index] = new_value;
1277 length = count;
1278
1279out:
1280 mutex_unlock(lock: &selinux_state.policy_mutex);
1281 kfree(objp: page);
1282 return length;
1283}
1284
1285static const struct file_operations sel_bool_ops = {
1286 .read = sel_read_bool,
1287 .write = sel_write_bool,
1288 .llseek = generic_file_llseek,
1289};
1290
1291static ssize_t sel_commit_bools_write(struct file *filep,
1292 const char __user *buf,
1293 size_t count, loff_t *ppos)
1294{
1295 struct selinux_fs_info *fsi = file_inode(f: filep)->i_sb->s_fs_info;
1296 char *page = NULL;
1297 ssize_t length;
1298 int new_value;
1299
1300 if (count >= PAGE_SIZE)
1301 return -ENOMEM;
1302
1303 /* No partial writes. */
1304 if (*ppos != 0)
1305 return -EINVAL;
1306
1307 page = memdup_user_nul(buf, count);
1308 if (IS_ERR(ptr: page))
1309 return PTR_ERR(ptr: page);
1310
1311 mutex_lock(lock: &selinux_state.policy_mutex);
1312
1313 length = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
1314 SECCLASS_SECURITY, SECURITY__SETBOOL,
1315 NULL);
1316 if (length)
1317 goto out;
1318
1319 length = -EINVAL;
1320 if (sscanf(page, "%d", &new_value) != 1)
1321 goto out;
1322
1323 length = 0;
1324 if (new_value && fsi->bool_pending_values)
1325 length = security_set_bools(len: fsi->bool_num,
1326 values: fsi->bool_pending_values);
1327
1328 if (!length)
1329 length = count;
1330
1331out:
1332 mutex_unlock(lock: &selinux_state.policy_mutex);
1333 kfree(objp: page);
1334 return length;
1335}
1336
1337static const struct file_operations sel_commit_bools_ops = {
1338 .write = sel_commit_bools_write,
1339 .llseek = generic_file_llseek,
1340};
1341
1342static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
1343 unsigned int *bool_num, char ***bool_pending_names,
1344 int **bool_pending_values)
1345{
1346 int ret;
1347 char **names, *page;
1348 u32 i, num;
1349
1350 page = (char *)get_zeroed_page(GFP_KERNEL);
1351 if (!page)
1352 return -ENOMEM;
1353
1354 ret = security_get_bools(policy: newpolicy, len: &num, names: &names, values: bool_pending_values);
1355 if (ret)
1356 goto out;
1357
1358 *bool_num = num;
1359 *bool_pending_names = names;
1360
1361 for (i = 0; i < num; i++) {
1362 struct dentry *dentry;
1363 struct inode *inode;
1364 struct inode_security_struct *isec;
1365 ssize_t len;
1366 u32 sid;
1367
1368 len = snprintf(buf: page, PAGE_SIZE, fmt: "/%s/%s", BOOL_DIR_NAME, names[i]);
1369 if (len >= PAGE_SIZE) {
1370 ret = -ENAMETOOLONG;
1371 break;
1372 }
1373 dentry = d_alloc_name(bool_dir, names[i]);
1374 if (!dentry) {
1375 ret = -ENOMEM;
1376 break;
1377 }
1378
1379 inode = sel_make_inode(sb: bool_dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1380 if (!inode) {
1381 dput(dentry);
1382 ret = -ENOMEM;
1383 break;
1384 }
1385
1386 isec = selinux_inode(inode);
1387 ret = selinux_policy_genfs_sid(policy: newpolicy, fstype: "selinuxfs", path: page,
1388 SECCLASS_FILE, sid: &sid);
1389 if (ret) {
1390 pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
1391 page);
1392 sid = SECINITSID_SECURITY;
1393 }
1394
1395 isec->sid = sid;
1396 isec->initialized = LABEL_INITIALIZED;
1397 inode->i_fop = &sel_bool_ops;
1398 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1399 d_add(dentry, inode);
1400 }
1401out:
1402 free_page((unsigned long)page);
1403 return ret;
1404}
1405
1406static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1407 size_t count, loff_t *ppos)
1408{
1409 char tmpbuf[TMPBUFLEN];
1410 ssize_t length;
1411
1412 length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%u",
1413 avc_get_cache_threshold());
1414 return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length);
1415}
1416
1417static ssize_t sel_write_avc_cache_threshold(struct file *file,
1418 const char __user *buf,
1419 size_t count, loff_t *ppos)
1420
1421{
1422 char *page;
1423 ssize_t ret;
1424 unsigned int new_value;
1425
1426 ret = avc_has_perm(ssid: current_sid(), SECINITSID_SECURITY,
1427 SECCLASS_SECURITY, SECURITY__SETSECPARAM,
1428 NULL);
1429 if (ret)
1430 return ret;
1431
1432 if (count >= PAGE_SIZE)
1433 return -ENOMEM;
1434
1435 /* No partial writes. */
1436 if (*ppos != 0)
1437 return -EINVAL;
1438
1439 page = memdup_user_nul(buf, count);
1440 if (IS_ERR(ptr: page))
1441 return PTR_ERR(ptr: page);
1442
1443 ret = -EINVAL;
1444 if (sscanf(page, "%u", &new_value) != 1)
1445 goto out;
1446
1447 avc_set_cache_threshold(cache_threshold: new_value);
1448
1449 ret = count;
1450out:
1451 kfree(objp: page);
1452 return ret;
1453}
1454
1455static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1456 size_t count, loff_t *ppos)
1457{
1458 char *page;
1459 ssize_t length;
1460
1461 page = (char *)__get_free_page(GFP_KERNEL);
1462 if (!page)
1463 return -ENOMEM;
1464
1465 length = avc_get_hash_stats(page);
1466 if (length >= 0)
1467 length = simple_read_from_buffer(to: buf, count, ppos, from: page, available: length);
1468 free_page((unsigned long)page);
1469
1470 return length;
1471}
1472
1473static ssize_t sel_read_sidtab_hash_stats(struct file *filp, char __user *buf,
1474 size_t count, loff_t *ppos)
1475{
1476 char *page;
1477 ssize_t length;
1478
1479 page = (char *)__get_free_page(GFP_KERNEL);
1480 if (!page)
1481 return -ENOMEM;
1482
1483 length = security_sidtab_hash_stats(page);
1484 if (length >= 0)
1485 length = simple_read_from_buffer(to: buf, count, ppos, from: page,
1486 available: length);
1487 free_page((unsigned long)page);
1488
1489 return length;
1490}
1491
1492static const struct file_operations sel_sidtab_hash_stats_ops = {
1493 .read = sel_read_sidtab_hash_stats,
1494 .llseek = generic_file_llseek,
1495};
1496
1497static const struct file_operations sel_avc_cache_threshold_ops = {
1498 .read = sel_read_avc_cache_threshold,
1499 .write = sel_write_avc_cache_threshold,
1500 .llseek = generic_file_llseek,
1501};
1502
1503static const struct file_operations sel_avc_hash_stats_ops = {
1504 .read = sel_read_avc_hash_stats,
1505 .llseek = generic_file_llseek,
1506};
1507
1508#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1509static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1510{
1511 loff_t cpu;
1512
1513 for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1514 if (!cpu_possible(cpu))
1515 continue;
1516 *idx = cpu + 1;
1517 return &per_cpu(avc_cache_stats, cpu);
1518 }
1519 (*idx)++;
1520 return NULL;
1521}
1522
1523static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1524{
1525 loff_t n = *pos - 1;
1526
1527 if (*pos == 0)
1528 return SEQ_START_TOKEN;
1529
1530 return sel_avc_get_stat_idx(idx: &n);
1531}
1532
1533static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1534{
1535 return sel_avc_get_stat_idx(idx: pos);
1536}
1537
1538static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1539{
1540 struct avc_cache_stats *st = v;
1541
1542 if (v == SEQ_START_TOKEN) {
1543 seq_puts(m: seq,
1544 s: "lookups hits misses allocations reclaims frees\n");
1545 } else {
1546 unsigned int lookups = st->lookups;
1547 unsigned int misses = st->misses;
1548 unsigned int hits = lookups - misses;
1549 seq_printf(m: seq, fmt: "%u %u %u %u %u %u\n", lookups,
1550 hits, misses, st->allocations,
1551 st->reclaims, st->frees);
1552 }
1553 return 0;
1554}
1555
1556static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1557{ }
1558
1559static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1560 .start = sel_avc_stats_seq_start,
1561 .next = sel_avc_stats_seq_next,
1562 .show = sel_avc_stats_seq_show,
1563 .stop = sel_avc_stats_seq_stop,
1564};
1565
1566static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1567{
1568 return seq_open(file, &sel_avc_cache_stats_seq_ops);
1569}
1570
1571static const struct file_operations sel_avc_cache_stats_ops = {
1572 .open = sel_open_avc_cache_stats,
1573 .read = seq_read,
1574 .llseek = seq_lseek,
1575 .release = seq_release,
1576};
1577#endif
1578
1579static int sel_make_avc_files(struct dentry *dir)
1580{
1581 struct super_block *sb = dir->d_sb;
1582 struct selinux_fs_info *fsi = sb->s_fs_info;
1583 unsigned int i;
1584 static const struct tree_descr files[] = {
1585 { "cache_threshold",
1586 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1587 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1588#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1589 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1590#endif
1591 };
1592
1593 for (i = 0; i < ARRAY_SIZE(files); i++) {
1594 struct inode *inode;
1595 struct dentry *dentry;
1596
1597 dentry = d_alloc_name(dir, files[i].name);
1598 if (!dentry)
1599 return -ENOMEM;
1600
1601 inode = sel_make_inode(sb: dir->d_sb, S_IFREG|files[i].mode);
1602 if (!inode) {
1603 dput(dentry);
1604 return -ENOMEM;
1605 }
1606
1607 inode->i_fop = files[i].ops;
1608 inode->i_ino = ++fsi->last_ino;
1609 d_add(dentry, inode);
1610 }
1611
1612 return 0;
1613}
1614
1615static int sel_make_ss_files(struct dentry *dir)
1616{
1617 struct super_block *sb = dir->d_sb;
1618 struct selinux_fs_info *fsi = sb->s_fs_info;
1619 unsigned int i;
1620 static const struct tree_descr files[] = {
1621 { "sidtab_hash_stats", &sel_sidtab_hash_stats_ops, S_IRUGO },
1622 };
1623
1624 for (i = 0; i < ARRAY_SIZE(files); i++) {
1625 struct inode *inode;
1626 struct dentry *dentry;
1627
1628 dentry = d_alloc_name(dir, files[i].name);
1629 if (!dentry)
1630 return -ENOMEM;
1631
1632 inode = sel_make_inode(sb: dir->d_sb, S_IFREG|files[i].mode);
1633 if (!inode) {
1634 dput(dentry);
1635 return -ENOMEM;
1636 }
1637
1638 inode->i_fop = files[i].ops;
1639 inode->i_ino = ++fsi->last_ino;
1640 d_add(dentry, inode);
1641 }
1642
1643 return 0;
1644}
1645
1646static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1647 size_t count, loff_t *ppos)
1648{
1649 char *con;
1650 u32 sid, len;
1651 ssize_t ret;
1652
1653 sid = file_inode(f: file)->i_ino&SEL_INO_MASK;
1654 ret = security_sid_to_context(sid, scontext: &con, scontext_len: &len);
1655 if (ret)
1656 return ret;
1657
1658 ret = simple_read_from_buffer(to: buf, count, ppos, from: con, available: len);
1659 kfree(objp: con);
1660 return ret;
1661}
1662
1663static const struct file_operations sel_initcon_ops = {
1664 .read = sel_read_initcon,
1665 .llseek = generic_file_llseek,
1666};
1667
1668static int sel_make_initcon_files(struct dentry *dir)
1669{
1670 unsigned int i;
1671
1672 for (i = 1; i <= SECINITSID_NUM; i++) {
1673 struct inode *inode;
1674 struct dentry *dentry;
1675 const char *s = security_get_initial_sid_context(sid: i);
1676
1677 if (!s)
1678 continue;
1679 dentry = d_alloc_name(dir, s);
1680 if (!dentry)
1681 return -ENOMEM;
1682
1683 inode = sel_make_inode(sb: dir->d_sb, S_IFREG|S_IRUGO);
1684 if (!inode) {
1685 dput(dentry);
1686 return -ENOMEM;
1687 }
1688
1689 inode->i_fop = &sel_initcon_ops;
1690 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1691 d_add(dentry, inode);
1692 }
1693
1694 return 0;
1695}
1696
1697static inline unsigned long sel_class_to_ino(u16 class)
1698{
1699 return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1700}
1701
1702static inline u16 sel_ino_to_class(unsigned long ino)
1703{
1704 return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1705}
1706
1707static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1708{
1709 return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1710}
1711
1712static inline u32 sel_ino_to_perm(unsigned long ino)
1713{
1714 return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1715}
1716
1717static ssize_t sel_read_class(struct file *file, char __user *buf,
1718 size_t count, loff_t *ppos)
1719{
1720 unsigned long ino = file_inode(f: file)->i_ino;
1721 char res[TMPBUFLEN];
1722 ssize_t len = scnprintf(buf: res, size: sizeof(res), fmt: "%d", sel_ino_to_class(ino));
1723 return simple_read_from_buffer(to: buf, count, ppos, from: res, available: len);
1724}
1725
1726static const struct file_operations sel_class_ops = {
1727 .read = sel_read_class,
1728 .llseek = generic_file_llseek,
1729};
1730
1731static ssize_t sel_read_perm(struct file *file, char __user *buf,
1732 size_t count, loff_t *ppos)
1733{
1734 unsigned long ino = file_inode(f: file)->i_ino;
1735 char res[TMPBUFLEN];
1736 ssize_t len = scnprintf(buf: res, size: sizeof(res), fmt: "%d", sel_ino_to_perm(ino));
1737 return simple_read_from_buffer(to: buf, count, ppos, from: res, available: len);
1738}
1739
1740static const struct file_operations sel_perm_ops = {
1741 .read = sel_read_perm,
1742 .llseek = generic_file_llseek,
1743};
1744
1745static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1746 size_t count, loff_t *ppos)
1747{
1748 int value;
1749 char tmpbuf[TMPBUFLEN];
1750 ssize_t length;
1751 unsigned long i_ino = file_inode(f: file)->i_ino;
1752
1753 value = security_policycap_supported(req_cap: i_ino & SEL_INO_MASK);
1754 length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%d", value);
1755
1756 return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length);
1757}
1758
1759static const struct file_operations sel_policycap_ops = {
1760 .read = sel_read_policycap,
1761 .llseek = generic_file_llseek,
1762};
1763
1764static int sel_make_perm_files(struct selinux_policy *newpolicy,
1765 char *objclass, int classvalue,
1766 struct dentry *dir)
1767{
1768 u32 i, nperms;
1769 int rc;
1770 char **perms;
1771
1772 rc = security_get_permissions(policy: newpolicy, class: objclass, perms: &perms, nperms: &nperms);
1773 if (rc)
1774 return rc;
1775
1776 for (i = 0; i < nperms; i++) {
1777 struct inode *inode;
1778 struct dentry *dentry;
1779
1780 rc = -ENOMEM;
1781 dentry = d_alloc_name(dir, perms[i]);
1782 if (!dentry)
1783 goto out;
1784
1785 rc = -ENOMEM;
1786 inode = sel_make_inode(sb: dir->d_sb, S_IFREG|S_IRUGO);
1787 if (!inode) {
1788 dput(dentry);
1789 goto out;
1790 }
1791
1792 inode->i_fop = &sel_perm_ops;
1793 /* i+1 since perm values are 1-indexed */
1794 inode->i_ino = sel_perm_to_ino(class: classvalue, perm: i + 1);
1795 d_add(dentry, inode);
1796 }
1797 rc = 0;
1798out:
1799 for (i = 0; i < nperms; i++)
1800 kfree(objp: perms[i]);
1801 kfree(objp: perms);
1802 return rc;
1803}
1804
1805static int sel_make_class_dir_entries(struct selinux_policy *newpolicy,
1806 char *classname, int index,
1807 struct dentry *dir)
1808{
1809 struct super_block *sb = dir->d_sb;
1810 struct selinux_fs_info *fsi = sb->s_fs_info;
1811 struct dentry *dentry = NULL;
1812 struct inode *inode = NULL;
1813
1814 dentry = d_alloc_name(dir, "index");
1815 if (!dentry)
1816 return -ENOMEM;
1817
1818 inode = sel_make_inode(sb: dir->d_sb, S_IFREG|S_IRUGO);
1819 if (!inode) {
1820 dput(dentry);
1821 return -ENOMEM;
1822 }
1823
1824 inode->i_fop = &sel_class_ops;
1825 inode->i_ino = sel_class_to_ino(class: index);
1826 d_add(dentry, inode);
1827
1828 dentry = sel_make_dir(dir, name: "perms", ino: &fsi->last_class_ino);
1829 if (IS_ERR(ptr: dentry))
1830 return PTR_ERR(ptr: dentry);
1831
1832 return sel_make_perm_files(newpolicy, objclass: classname, classvalue: index, dir: dentry);
1833}
1834
1835static int sel_make_classes(struct selinux_policy *newpolicy,
1836 struct dentry *class_dir,
1837 unsigned long *last_class_ino)
1838{
1839 u32 i, nclasses;
1840 int rc;
1841 char **classes;
1842
1843 rc = security_get_classes(policy: newpolicy, classes: &classes, nclasses: &nclasses);
1844 if (rc)
1845 return rc;
1846
1847 /* +2 since classes are 1-indexed */
1848 *last_class_ino = sel_class_to_ino(class: nclasses + 2);
1849
1850 for (i = 0; i < nclasses; i++) {
1851 struct dentry *class_name_dir;
1852
1853 class_name_dir = sel_make_dir(dir: class_dir, name: classes[i],
1854 ino: last_class_ino);
1855 if (IS_ERR(ptr: class_name_dir)) {
1856 rc = PTR_ERR(ptr: class_name_dir);
1857 goto out;
1858 }
1859
1860 /* i+1 since class values are 1-indexed */
1861 rc = sel_make_class_dir_entries(newpolicy, classname: classes[i], index: i + 1,
1862 dir: class_name_dir);
1863 if (rc)
1864 goto out;
1865 }
1866 rc = 0;
1867out:
1868 for (i = 0; i < nclasses; i++)
1869 kfree(objp: classes[i]);
1870 kfree(objp: classes);
1871 return rc;
1872}
1873
1874static int sel_make_policycap(struct selinux_fs_info *fsi)
1875{
1876 unsigned int iter;
1877 struct dentry *dentry = NULL;
1878 struct inode *inode = NULL;
1879
1880 for (iter = 0; iter <= POLICYDB_CAP_MAX; iter++) {
1881 if (iter < ARRAY_SIZE(selinux_policycap_names))
1882 dentry = d_alloc_name(fsi->policycap_dir,
1883 selinux_policycap_names[iter]);
1884 else
1885 dentry = d_alloc_name(fsi->policycap_dir, "unknown");
1886
1887 if (dentry == NULL)
1888 return -ENOMEM;
1889
1890 inode = sel_make_inode(sb: fsi->sb, S_IFREG | 0444);
1891 if (inode == NULL) {
1892 dput(dentry);
1893 return -ENOMEM;
1894 }
1895
1896 inode->i_fop = &sel_policycap_ops;
1897 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1898 d_add(dentry, inode);
1899 }
1900
1901 return 0;
1902}
1903
1904static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1905 unsigned long *ino)
1906{
1907 struct dentry *dentry = d_alloc_name(dir, name);
1908 struct inode *inode;
1909
1910 if (!dentry)
1911 return ERR_PTR(error: -ENOMEM);
1912
1913 inode = sel_make_inode(sb: dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1914 if (!inode) {
1915 dput(dentry);
1916 return ERR_PTR(error: -ENOMEM);
1917 }
1918
1919 inode->i_op = &simple_dir_inode_operations;
1920 inode->i_fop = &simple_dir_operations;
1921 inode->i_ino = ++(*ino);
1922 /* directory inodes start off with i_nlink == 2 (for "." entry) */
1923 inc_nlink(inode);
1924 d_add(dentry, inode);
1925 /* bump link count on parent directory, too */
1926 inc_nlink(inode: d_inode(dentry: dir));
1927
1928 return dentry;
1929}
1930
1931static int reject_all(struct mnt_idmap *idmap, struct inode *inode, int mask)
1932{
1933 return -EPERM; // no access for anyone, root or no root.
1934}
1935
1936static const struct inode_operations swapover_dir_inode_operations = {
1937 .lookup = simple_lookup,
1938 .permission = reject_all,
1939};
1940
1941static struct dentry *sel_make_swapover_dir(struct super_block *sb,
1942 unsigned long *ino)
1943{
1944 struct dentry *dentry = d_alloc_name(sb->s_root, ".swapover");
1945 struct inode *inode;
1946
1947 if (!dentry)
1948 return ERR_PTR(error: -ENOMEM);
1949
1950 inode = sel_make_inode(sb, S_IFDIR);
1951 if (!inode) {
1952 dput(dentry);
1953 return ERR_PTR(error: -ENOMEM);
1954 }
1955
1956 inode->i_op = &swapover_dir_inode_operations;
1957 inode->i_ino = ++(*ino);
1958 /* directory inodes start off with i_nlink == 2 (for "." entry) */
1959 inc_nlink(inode);
1960 inode_lock(inode: sb->s_root->d_inode);
1961 d_add(dentry, inode);
1962 inc_nlink(inode: sb->s_root->d_inode);
1963 inode_unlock(inode: sb->s_root->d_inode);
1964 return dentry;
1965}
1966
1967#define NULL_FILE_NAME "null"
1968
1969static int sel_fill_super(struct super_block *sb, struct fs_context *fc)
1970{
1971 struct selinux_fs_info *fsi;
1972 int ret;
1973 struct dentry *dentry;
1974 struct inode *inode;
1975 struct inode_security_struct *isec;
1976
1977 static const struct tree_descr selinux_files[] = {
1978 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1979 [SEL_ENFORCE] = {.name: "enforce", .ops: &sel_enforce_ops, S_IRUGO|S_IWUSR},
1980 [SEL_CONTEXT] = {.name: "context", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1981 [SEL_ACCESS] = {.name: "access", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1982 [SEL_CREATE] = {.name: "create", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1983 [SEL_RELABEL] = {.name: "relabel", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1984 [SEL_USER] = {.name: "user", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1985 [SEL_POLICYVERS] = {.name: "policyvers", .ops: &sel_policyvers_ops, S_IRUGO},
1986 [SEL_COMMIT_BOOLS] = {.name: "commit_pending_bools", .ops: &sel_commit_bools_ops, S_IWUSR},
1987 [SEL_MLS] = {.name: "mls", .ops: &sel_mls_ops, S_IRUGO},
1988 [SEL_DISABLE] = {.name: "disable", .ops: &sel_disable_ops, S_IWUSR},
1989 [SEL_MEMBER] = {.name: "member", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1990 [SEL_CHECKREQPROT] = {.name: "checkreqprot", .ops: &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1991 [SEL_REJECT_UNKNOWN] = {.name: "reject_unknown", .ops: &sel_handle_unknown_ops, S_IRUGO},
1992 [SEL_DENY_UNKNOWN] = {.name: "deny_unknown", .ops: &sel_handle_unknown_ops, S_IRUGO},
1993 [SEL_STATUS] = {.name: "status", .ops: &sel_handle_status_ops, S_IRUGO},
1994 [SEL_POLICY] = {.name: "policy", .ops: &sel_policy_ops, S_IRUGO},
1995 [SEL_VALIDATE_TRANS] = {.name: "validatetrans", .ops: &sel_transition_ops,
1996 S_IWUGO},
1997 /* last one */ {"", NULL, 0}
1998 };
1999
2000 ret = selinux_fs_info_create(sb);
2001 if (ret)
2002 goto err;
2003
2004 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
2005 if (ret)
2006 goto err;
2007
2008 fsi = sb->s_fs_info;
2009 fsi->bool_dir = sel_make_dir(dir: sb->s_root, BOOL_DIR_NAME, ino: &fsi->last_ino);
2010 if (IS_ERR(ptr: fsi->bool_dir)) {
2011 ret = PTR_ERR(ptr: fsi->bool_dir);
2012 fsi->bool_dir = NULL;
2013 goto err;
2014 }
2015
2016 ret = -ENOMEM;
2017 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
2018 if (!dentry)
2019 goto err;
2020
2021 ret = -ENOMEM;
2022 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
2023 if (!inode) {
2024 dput(dentry);
2025 goto err;
2026 }
2027
2028 inode->i_ino = ++fsi->last_ino;
2029 isec = selinux_inode(inode);
2030 isec->sid = SECINITSID_DEVNULL;
2031 isec->sclass = SECCLASS_CHR_FILE;
2032 isec->initialized = LABEL_INITIALIZED;
2033
2034 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
2035 d_add(dentry, inode);
2036
2037 dentry = sel_make_dir(dir: sb->s_root, name: "avc", ino: &fsi->last_ino);
2038 if (IS_ERR(ptr: dentry)) {
2039 ret = PTR_ERR(ptr: dentry);
2040 goto err;
2041 }
2042
2043 ret = sel_make_avc_files(dir: dentry);
2044 if (ret)
2045 goto err;
2046
2047 dentry = sel_make_dir(dir: sb->s_root, name: "ss", ino: &fsi->last_ino);
2048 if (IS_ERR(ptr: dentry)) {
2049 ret = PTR_ERR(ptr: dentry);
2050 goto err;
2051 }
2052
2053 ret = sel_make_ss_files(dir: dentry);
2054 if (ret)
2055 goto err;
2056
2057 dentry = sel_make_dir(dir: sb->s_root, name: "initial_contexts", ino: &fsi->last_ino);
2058 if (IS_ERR(ptr: dentry)) {
2059 ret = PTR_ERR(ptr: dentry);
2060 goto err;
2061 }
2062
2063 ret = sel_make_initcon_files(dir: dentry);
2064 if (ret)
2065 goto err;
2066
2067 fsi->class_dir = sel_make_dir(dir: sb->s_root, CLASS_DIR_NAME, ino: &fsi->last_ino);
2068 if (IS_ERR(ptr: fsi->class_dir)) {
2069 ret = PTR_ERR(ptr: fsi->class_dir);
2070 fsi->class_dir = NULL;
2071 goto err;
2072 }
2073
2074 fsi->policycap_dir = sel_make_dir(dir: sb->s_root, POLICYCAP_DIR_NAME,
2075 ino: &fsi->last_ino);
2076 if (IS_ERR(ptr: fsi->policycap_dir)) {
2077 ret = PTR_ERR(ptr: fsi->policycap_dir);
2078 fsi->policycap_dir = NULL;
2079 goto err;
2080 }
2081
2082 ret = sel_make_policycap(fsi);
2083 if (ret) {
2084 pr_err("SELinux: failed to load policy capabilities\n");
2085 goto err;
2086 }
2087
2088 return 0;
2089err:
2090 pr_err("SELinux: %s: failed while creating inodes\n",
2091 __func__);
2092
2093 return ret;
2094}
2095
2096static int sel_get_tree(struct fs_context *fc)
2097{
2098 return get_tree_single(fc, fill_super: sel_fill_super);
2099}
2100
2101static const struct fs_context_operations sel_context_ops = {
2102 .get_tree = sel_get_tree,
2103};
2104
2105static int sel_init_fs_context(struct fs_context *fc)
2106{
2107 fc->ops = &sel_context_ops;
2108 return 0;
2109}
2110
2111static void sel_kill_sb(struct super_block *sb)
2112{
2113 selinux_fs_info_free(sb);
2114 kill_litter_super(sb);
2115}
2116
2117static struct file_system_type sel_fs_type = {
2118 .name = "selinuxfs",
2119 .init_fs_context = sel_init_fs_context,
2120 .kill_sb = sel_kill_sb,
2121};
2122
2123struct path selinux_null __ro_after_init;
2124
2125static int __init init_sel_fs(void)
2126{
2127 struct qstr null_name = QSTR_INIT(NULL_FILE_NAME,
2128 sizeof(NULL_FILE_NAME)-1);
2129 int err;
2130
2131 if (!selinux_enabled_boot)
2132 return 0;
2133
2134 err = sysfs_create_mount_point(parent_kobj: fs_kobj, name: "selinux");
2135 if (err)
2136 return err;
2137
2138 err = register_filesystem(&sel_fs_type);
2139 if (err) {
2140 sysfs_remove_mount_point(parent_kobj: fs_kobj, name: "selinux");
2141 return err;
2142 }
2143
2144 selinux_null.mnt = kern_mount(&sel_fs_type);
2145 if (IS_ERR(ptr: selinux_null.mnt)) {
2146 pr_err("selinuxfs: could not mount!\n");
2147 err = PTR_ERR(ptr: selinux_null.mnt);
2148 selinux_null.mnt = NULL;
2149 return err;
2150 }
2151
2152 selinux_null.dentry = try_lookup_noperm(&null_name,
2153 selinux_null.mnt->mnt_root);
2154 if (IS_ERR(ptr: selinux_null.dentry)) {
2155 pr_err("selinuxfs: could not lookup null!\n");
2156 err = PTR_ERR(ptr: selinux_null.dentry);
2157 selinux_null.dentry = NULL;
2158 return err;
2159 }
2160
2161 /*
2162 * Try to pre-allocate the status page, so the sequence number of the
2163 * initial policy load can be stored.
2164 */
2165 (void) selinux_kernel_status_page();
2166
2167 return err;
2168}
2169
2170__initcall(init_sel_fs);
2171