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1// SPDX-License-Identifier: GPL-2.0-only
2/* Updated: Karl MacMillan <kmacmillan@tresys.com>
3 *
4 * Added conditional policy language extensions
5 *
6 * Updated: Hewlett-Packard <paul@paul-moore.com>
7 *
8 * Added support for the policy capability bitmap
9 *
10 * Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
11 * Copyright (C) 2003 - 2004 Tresys Technology, LLC
12 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 */
14
15#include <linux/kernel.h>
16#include <linux/pagemap.h>
17#include <linux/slab.h>
18#include <linux/vmalloc.h>
19#include <linux/fs.h>
20#include <linux/fs_context.h>
21#include <linux/mount.h>
22#include <linux/mutex.h>
23#include <linux/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);
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 unsigned 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 selinux_state *state;
81 struct super_block *sb;
82};
83
84static int selinux_fs_info_create(struct super_block *sb)
85{
86 struct selinux_fs_info *fsi;
87
88 fsi = kzalloc(sizeof(*fsi), GFP_KERNEL);
89 if (!fsi)
90 return -ENOMEM;
91
92 fsi->last_ino = SEL_INO_NEXT - 1;
93 fsi->state = &selinux_state;
94 fsi->sb = sb;
95 sb->s_fs_info = fsi;
96 return 0;
97}
98
99static void selinux_fs_info_free(struct super_block *sb)
100{
101 struct selinux_fs_info *fsi = sb->s_fs_info;
102 int i;
103
104 if (fsi) {
105 for (i = 0; i < fsi->bool_num; i++)
106 kfree(fsi->bool_pending_names[i]);
107 kfree(fsi->bool_pending_names);
108 kfree(fsi->bool_pending_values);
109 }
110 kfree(sb->s_fs_info);
111 sb->s_fs_info = NULL;
112}
113
114#define SEL_INITCON_INO_OFFSET 0x01000000
115#define SEL_BOOL_INO_OFFSET 0x02000000
116#define SEL_CLASS_INO_OFFSET 0x04000000
117#define SEL_POLICYCAP_INO_OFFSET 0x08000000
118#define SEL_INO_MASK 0x00ffffff
119
120#define BOOL_DIR_NAME "booleans"
121#define CLASS_DIR_NAME "class"
122#define POLICYCAP_DIR_NAME "policy_capabilities"
123
124#define TMPBUFLEN 12
125static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
126 size_t count, loff_t *ppos)
127{
128 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
129 char tmpbuf[TMPBUFLEN];
130 ssize_t length;
131
132 length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
133 enforcing_enabled(fsi->state));
134 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
135}
136
137#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
138static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
139 size_t count, loff_t *ppos)
140
141{
142 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
143 struct selinux_state *state = fsi->state;
144 char *page = NULL;
145 ssize_t length;
146 int old_value, new_value;
147
148 if (count >= PAGE_SIZE)
149 return -ENOMEM;
150
151 /* No partial writes. */
152 if (*ppos != 0)
153 return -EINVAL;
154
155 page = memdup_user_nul(buf, count);
156 if (IS_ERR(page))
157 return PTR_ERR(page);
158
159 length = -EINVAL;
160 if (sscanf(page, "%d", &new_value) != 1)
161 goto out;
162
163 new_value = !!new_value;
164
165 old_value = enforcing_enabled(state);
166 if (new_value != old_value) {
167 length = avc_has_perm(&selinux_state,
168 current_sid(), SECINITSID_SECURITY,
169 SECCLASS_SECURITY, SECURITY__SETENFORCE,
170 NULL);
171 if (length)
172 goto out;
173 audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
174 "enforcing=%d old_enforcing=%d auid=%u ses=%u"
175 " enabled=1 old-enabled=1 lsm=selinux res=1",
176 new_value, old_value,
177 from_kuid(&init_user_ns, audit_get_loginuid(current)),
178 audit_get_sessionid(current));
179 enforcing_set(state, new_value);
180 if (new_value)
181 avc_ss_reset(state->avc, 0);
182 selnl_notify_setenforce(new_value);
183 selinux_status_update_setenforce(state, new_value);
184 if (!new_value)
185 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
186
187 selinux_ima_measure_state(state);
188 }
189 length = count;
190out:
191 kfree(page);
192 return length;
193}
194#else
195#define sel_write_enforce NULL
196#endif
197
198static const struct file_operations sel_enforce_ops = {
199 .read = sel_read_enforce,
200 .write = sel_write_enforce,
201 .llseek = generic_file_llseek,
202};
203
204static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
205 size_t count, loff_t *ppos)
206{
207 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
208 struct selinux_state *state = fsi->state;
209 char tmpbuf[TMPBUFLEN];
210 ssize_t length;
211 ino_t ino = file_inode(filp)->i_ino;
212 int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
213 security_get_reject_unknown(state) :
214 !security_get_allow_unknown(state);
215
216 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
217 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
218}
219
220static const struct file_operations sel_handle_unknown_ops = {
221 .read = sel_read_handle_unknown,
222 .llseek = generic_file_llseek,
223};
224
225static int sel_open_handle_status(struct inode *inode, struct file *filp)
226{
227 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
228 struct page *status = selinux_kernel_status_page(fsi->state);
229
230 if (!status)
231 return -ENOMEM;
232
233 filp->private_data = status;
234
235 return 0;
236}
237
238static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
239 size_t count, loff_t *ppos)
240{
241 struct page *status = filp->private_data;
242
243 BUG_ON(!status);
244
245 return simple_read_from_buffer(buf, count, ppos,
246 page_address(status),
247 sizeof(struct selinux_kernel_status));
248}
249
250static int sel_mmap_handle_status(struct file *filp,
251 struct vm_area_struct *vma)
252{
253 struct page *status = filp->private_data;
254 unsigned long size = vma->vm_end - vma->vm_start;
255
256 BUG_ON(!status);
257
258 /* only allows one page from the head */
259 if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
260 return -EIO;
261 /* disallow writable mapping */
262 if (vma->vm_flags & VM_WRITE)
263 return -EPERM;
264 /* disallow mprotect() turns it into writable */
265 vma->vm_flags &= ~VM_MAYWRITE;
266
267 return remap_pfn_range(vma, vma->vm_start,
268 page_to_pfn(status),
269 size, vma->vm_page_prot);
270}
271
272static const struct file_operations sel_handle_status_ops = {
273 .open = sel_open_handle_status,
274 .read = sel_read_handle_status,
275 .mmap = sel_mmap_handle_status,
276 .llseek = generic_file_llseek,
277};
278
279#ifdef CONFIG_SECURITY_SELINUX_DISABLE
280static ssize_t sel_write_disable(struct file *file, const char __user *buf,
281 size_t count, loff_t *ppos)
282
283{
284 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
285 char *page;
286 ssize_t length;
287 int new_value;
288 int enforcing;
289
290 /* NOTE: we are now officially considering runtime disable as
291 * deprecated, and using it will become increasingly painful
292 * (e.g. sleeping/blocking) as we progress through future
293 * kernel releases until eventually it is removed
294 */
295 pr_err("SELinux: Runtime disable is deprecated, use selinux=0 on the kernel cmdline.\n");
296
297 if (count >= PAGE_SIZE)
298 return -ENOMEM;
299
300 /* No partial writes. */
301 if (*ppos != 0)
302 return -EINVAL;
303
304 page = memdup_user_nul(buf, count);
305 if (IS_ERR(page))
306 return PTR_ERR(page);
307
308 length = -EINVAL;
309 if (sscanf(page, "%d", &new_value) != 1)
310 goto out;
311
312 if (new_value) {
313 enforcing = enforcing_enabled(fsi->state);
314 length = selinux_disable(fsi->state);
315 if (length)
316 goto out;
317 audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
318 "enforcing=%d old_enforcing=%d auid=%u ses=%u"
319 " enabled=0 old-enabled=1 lsm=selinux res=1",
320 enforcing, enforcing,
321 from_kuid(&init_user_ns, audit_get_loginuid(current)),
322 audit_get_sessionid(current));
323 }
324
325 length = count;
326out:
327 kfree(page);
328 return length;
329}
330#else
331#define sel_write_disable NULL
332#endif
333
334static const struct file_operations sel_disable_ops = {
335 .write = sel_write_disable,
336 .llseek = generic_file_llseek,
337};
338
339static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
340 size_t count, loff_t *ppos)
341{
342 char tmpbuf[TMPBUFLEN];
343 ssize_t length;
344
345 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
346 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
347}
348
349static const struct file_operations sel_policyvers_ops = {
350 .read = sel_read_policyvers,
351 .llseek = generic_file_llseek,
352};
353
354/* declaration for sel_write_load */
355static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
356 unsigned int *bool_num, char ***bool_pending_names,
357 unsigned int **bool_pending_values);
358static int sel_make_classes(struct selinux_policy *newpolicy,
359 struct dentry *class_dir,
360 unsigned long *last_class_ino);
361
362/* declaration for sel_make_class_dirs */
363static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
364 unsigned long *ino);
365
366/* declaration for sel_make_policy_nodes */
367static struct dentry *sel_make_disconnected_dir(struct super_block *sb,
368 unsigned long *ino);
369
370/* declaration for sel_make_policy_nodes */
371static void sel_remove_entries(struct dentry *de);
372
373static ssize_t sel_read_mls(struct file *filp, char __user *buf,
374 size_t count, loff_t *ppos)
375{
376 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
377 char tmpbuf[TMPBUFLEN];
378 ssize_t length;
379
380 length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
381 security_mls_enabled(fsi->state));
382 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
383}
384
385static const struct file_operations sel_mls_ops = {
386 .read = sel_read_mls,
387 .llseek = generic_file_llseek,
388};
389
390struct policy_load_memory {
391 size_t len;
392 void *data;
393};
394
395static int sel_open_policy(struct inode *inode, struct file *filp)
396{
397 struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
398 struct selinux_state *state = fsi->state;
399 struct policy_load_memory *plm = NULL;
400 int rc;
401
402 BUG_ON(filp->private_data);
403
404 mutex_lock(&fsi->state->policy_mutex);
405
406 rc = avc_has_perm(&selinux_state,
407 current_sid(), SECINITSID_SECURITY,
408 SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
409 if (rc)
410 goto err;
411
412 rc = -EBUSY;
413 if (fsi->policy_opened)
414 goto err;
415
416 rc = -ENOMEM;
417 plm = kzalloc(sizeof(*plm), GFP_KERNEL);
418 if (!plm)
419 goto err;
420
421 rc = security_read_policy(state, &plm->data, &plm->len);
422 if (rc)
423 goto err;
424
425 if ((size_t)i_size_read(inode) != plm->len) {
426 inode_lock(inode);
427 i_size_write(inode, plm->len);
428 inode_unlock(inode);
429 }
430
431 fsi->policy_opened = 1;
432
433 filp->private_data = plm;
434
435 mutex_unlock(&fsi->state->policy_mutex);
436
437 return 0;
438err:
439 mutex_unlock(&fsi->state->policy_mutex);
440
441 if (plm)
442 vfree(plm->data);
443 kfree(plm);
444 return rc;
445}
446
447static int sel_release_policy(struct inode *inode, struct file *filp)
448{
449 struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
450 struct policy_load_memory *plm = filp->private_data;
451
452 BUG_ON(!plm);
453
454 fsi->policy_opened = 0;
455
456 vfree(plm->data);
457 kfree(plm);
458
459 return 0;
460}
461
462static ssize_t sel_read_policy(struct file *filp, char __user *buf,
463 size_t count, loff_t *ppos)
464{
465 struct policy_load_memory *plm = filp->private_data;
466 int ret;
467
468 ret = avc_has_perm(&selinux_state,
469 current_sid(), SECINITSID_SECURITY,
470 SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
471 if (ret)
472 return ret;
473
474 return simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
475}
476
477static vm_fault_t sel_mmap_policy_fault(struct vm_fault *vmf)
478{
479 struct policy_load_memory *plm = vmf->vma->vm_file->private_data;
480 unsigned long offset;
481 struct page *page;
482
483 if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
484 return VM_FAULT_SIGBUS;
485
486 offset = vmf->pgoff << PAGE_SHIFT;
487 if (offset >= roundup(plm->len, PAGE_SIZE))
488 return VM_FAULT_SIGBUS;
489
490 page = vmalloc_to_page(plm->data + offset);
491 get_page(page);
492
493 vmf->page = page;
494
495 return 0;
496}
497
498static const struct vm_operations_struct sel_mmap_policy_ops = {
499 .fault = sel_mmap_policy_fault,
500 .page_mkwrite = sel_mmap_policy_fault,
501};
502
503static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
504{
505 if (vma->vm_flags & VM_SHARED) {
506 /* do not allow mprotect to make mapping writable */
507 vma->vm_flags &= ~VM_MAYWRITE;
508
509 if (vma->vm_flags & VM_WRITE)
510 return -EACCES;
511 }
512
513 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
514 vma->vm_ops = &sel_mmap_policy_ops;
515
516 return 0;
517}
518
519static const struct file_operations sel_policy_ops = {
520 .open = sel_open_policy,
521 .read = sel_read_policy,
522 .mmap = sel_mmap_policy,
523 .release = sel_release_policy,
524 .llseek = generic_file_llseek,
525};
526
527static void sel_remove_old_bool_data(unsigned int bool_num, char **bool_names,
528 unsigned int *bool_values)
529{
530 u32 i;
531
532 /* bool_dir cleanup */
533 for (i = 0; i < bool_num; i++)
534 kfree(bool_names[i]);
535 kfree(bool_names);
536 kfree(bool_values);
537}
538
539static int sel_make_policy_nodes(struct selinux_fs_info *fsi,
540 struct selinux_policy *newpolicy)
541{
542 int ret = 0;
543 struct dentry *tmp_parent, *tmp_bool_dir, *tmp_class_dir, *old_dentry;
544 unsigned int tmp_bool_num, old_bool_num;
545 char **tmp_bool_names, **old_bool_names;
546 unsigned int *tmp_bool_values, *old_bool_values;
547 unsigned long tmp_ino = fsi->last_ino; /* Don't increment last_ino in this function */
548
549 tmp_parent = sel_make_disconnected_dir(fsi->sb, &tmp_ino);
550 if (IS_ERR(tmp_parent))
551 return PTR_ERR(tmp_parent);
552
553 tmp_ino = fsi->bool_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
554 tmp_bool_dir = sel_make_dir(tmp_parent, BOOL_DIR_NAME, &tmp_ino);
555 if (IS_ERR(tmp_bool_dir)) {
556 ret = PTR_ERR(tmp_bool_dir);
557 goto out;
558 }
559
560 tmp_ino = fsi->class_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
561 tmp_class_dir = sel_make_dir(tmp_parent, CLASS_DIR_NAME, &tmp_ino);
562 if (IS_ERR(tmp_class_dir)) {
563 ret = PTR_ERR(tmp_class_dir);
564 goto out;
565 }
566
567 ret = sel_make_bools(newpolicy, tmp_bool_dir, &tmp_bool_num,
568 &tmp_bool_names, &tmp_bool_values);
569 if (ret)
570 goto out;
571
572 ret = sel_make_classes(newpolicy, tmp_class_dir,
573 &fsi->last_class_ino);
574 if (ret)
575 goto out;
576
577 /* booleans */
578 old_dentry = fsi->bool_dir;
579 lock_rename(tmp_bool_dir, old_dentry);
580 d_exchange(tmp_bool_dir, fsi->bool_dir);
581
582 old_bool_num = fsi->bool_num;
583 old_bool_names = fsi->bool_pending_names;
584 old_bool_values = fsi->bool_pending_values;
585
586 fsi->bool_num = tmp_bool_num;
587 fsi->bool_pending_names = tmp_bool_names;
588 fsi->bool_pending_values = tmp_bool_values;
589
590 sel_remove_old_bool_data(old_bool_num, old_bool_names, old_bool_values);
591
592 fsi->bool_dir = tmp_bool_dir;
593 unlock_rename(tmp_bool_dir, old_dentry);
594
595 /* classes */
596 old_dentry = fsi->class_dir;
597 lock_rename(tmp_class_dir, old_dentry);
598 d_exchange(tmp_class_dir, fsi->class_dir);
599 fsi->class_dir = tmp_class_dir;
600 unlock_rename(tmp_class_dir, old_dentry);
601
602out:
603 /* Since the other temporary dirs are children of tmp_parent
604 * this will handle all the cleanup in the case of a failure before
605 * the swapover
606 */
607 sel_remove_entries(tmp_parent);
608 dput(tmp_parent); /* d_genocide() only handles the children */
609
610 return ret;
611}
612
613static ssize_t sel_write_load(struct file *file, const char __user *buf,
614 size_t count, loff_t *ppos)
615
616{
617 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
618 struct selinux_load_state load_state;
619 ssize_t length;
620 void *data = NULL;
621
622 mutex_lock(&fsi->state->policy_mutex);
623
624 length = avc_has_perm(&selinux_state,
625 current_sid(), SECINITSID_SECURITY,
626 SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
627 if (length)
628 goto out;
629
630 /* No partial writes. */
631 length = -EINVAL;
632 if (*ppos != 0)
633 goto out;
634
635 length = -ENOMEM;
636 data = vmalloc(count);
637 if (!data)
638 goto out;
639
640 length = -EFAULT;
641 if (copy_from_user(data, buf, count) != 0)
642 goto out;
643
644 length = security_load_policy(fsi->state, data, count, &load_state);
645 if (length) {
646 pr_warn_ratelimited("SELinux: failed to load policy\n");
647 goto out;
648 }
649
650 length = sel_make_policy_nodes(fsi, load_state.policy);
651 if (length) {
652 pr_warn_ratelimited("SELinux: failed to initialize selinuxfs\n");
653 selinux_policy_cancel(fsi->state, &load_state);
654 goto out;
655 }
656
657 selinux_policy_commit(fsi->state, &load_state);
658
659 length = count;
660
661 audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
662 "auid=%u ses=%u lsm=selinux res=1",
663 from_kuid(&init_user_ns, audit_get_loginuid(current)),
664 audit_get_sessionid(current));
665out:
666 mutex_unlock(&fsi->state->policy_mutex);
667 vfree(data);
668 return length;
669}
670
671static const struct file_operations sel_load_ops = {
672 .write = sel_write_load,
673 .llseek = generic_file_llseek,
674};
675
676static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
677{
678 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
679 struct selinux_state *state = fsi->state;
680 char *canon = NULL;
681 u32 sid, len;
682 ssize_t length;
683
684 length = avc_has_perm(&selinux_state,
685 current_sid(), SECINITSID_SECURITY,
686 SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
687 if (length)
688 goto out;
689
690 length = security_context_to_sid(state, buf, size, &sid, GFP_KERNEL);
691 if (length)
692 goto out;
693
694 length = security_sid_to_context(state, sid, &canon, &len);
695 if (length)
696 goto out;
697
698 length = -ERANGE;
699 if (len > SIMPLE_TRANSACTION_LIMIT) {
700 pr_err("SELinux: %s: context size (%u) exceeds "
701 "payload max\n", __func__, len);
702 goto out;
703 }
704
705 memcpy(buf, canon, len);
706 length = len;
707out:
708 kfree(canon);
709 return length;
710}
711
712static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
713 size_t count, loff_t *ppos)
714{
715 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
716 char tmpbuf[TMPBUFLEN];
717 ssize_t length;
718
719 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
720 checkreqprot_get(fsi->state));
721 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
722}
723
724static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
725 size_t count, loff_t *ppos)
726{
727 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
728 char *page;
729 ssize_t length;
730 unsigned int new_value;
731
732 length = avc_has_perm(&selinux_state,
733 current_sid(), SECINITSID_SECURITY,
734 SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
735 NULL);
736 if (length)
737 return length;
738
739 if (count >= PAGE_SIZE)
740 return -ENOMEM;
741
742 /* No partial writes. */
743 if (*ppos != 0)
744 return -EINVAL;
745
746 page = memdup_user_nul(buf, count);
747 if (IS_ERR(page))
748 return PTR_ERR(page);
749
750 length = -EINVAL;
751 if (sscanf(page, "%u", &new_value) != 1)
752 goto out;
753
754 if (new_value) {
755 char comm[sizeof(current->comm)];
756
757 memcpy(comm, current->comm, sizeof(comm));
758 pr_warn_once("SELinux: %s (%d) set checkreqprot to 1. This is deprecated and will be rejected in a future kernel release.\n",
759 comm, current->pid);
760 }
761
762 checkreqprot_set(fsi->state, (new_value ? 1 : 0));
763 length = count;
764
765 selinux_ima_measure_state(fsi->state);
766
767out:
768 kfree(page);
769 return length;
770}
771static const struct file_operations sel_checkreqprot_ops = {
772 .read = sel_read_checkreqprot,
773 .write = sel_write_checkreqprot,
774 .llseek = generic_file_llseek,
775};
776
777static ssize_t sel_write_validatetrans(struct file *file,
778 const char __user *buf,
779 size_t count, loff_t *ppos)
780{
781 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
782 struct selinux_state *state = fsi->state;
783 char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
784 char *req = NULL;
785 u32 osid, nsid, tsid;
786 u16 tclass;
787 int rc;
788
789 rc = avc_has_perm(&selinux_state,
790 current_sid(), SECINITSID_SECURITY,
791 SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
792 if (rc)
793 goto out;
794
795 rc = -ENOMEM;
796 if (count >= PAGE_SIZE)
797 goto out;
798
799 /* No partial writes. */
800 rc = -EINVAL;
801 if (*ppos != 0)
802 goto out;
803
804 req = memdup_user_nul(buf, count);
805 if (IS_ERR(req)) {
806 rc = PTR_ERR(req);
807 req = NULL;
808 goto out;
809 }
810
811 rc = -ENOMEM;
812 oldcon = kzalloc(count + 1, GFP_KERNEL);
813 if (!oldcon)
814 goto out;
815
816 newcon = kzalloc(count + 1, GFP_KERNEL);
817 if (!newcon)
818 goto out;
819
820 taskcon = kzalloc(count + 1, GFP_KERNEL);
821 if (!taskcon)
822 goto out;
823
824 rc = -EINVAL;
825 if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
826 goto out;
827
828 rc = security_context_str_to_sid(state, oldcon, &osid, GFP_KERNEL);
829 if (rc)
830 goto out;
831
832 rc = security_context_str_to_sid(state, newcon, &nsid, GFP_KERNEL);
833 if (rc)
834 goto out;
835
836 rc = security_context_str_to_sid(state, taskcon, &tsid, GFP_KERNEL);
837 if (rc)
838 goto out;
839
840 rc = security_validate_transition_user(state, osid, nsid, tsid, tclass);
841 if (!rc)
842 rc = count;
843out:
844 kfree(req);
845 kfree(oldcon);
846 kfree(newcon);
847 kfree(taskcon);
848 return rc;
849}
850
851static const struct file_operations sel_transition_ops = {
852 .write = sel_write_validatetrans,
853 .llseek = generic_file_llseek,
854};
855
856/*
857 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
858 */
859static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
860static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
861static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
862static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
863static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
864
865static ssize_t (*const write_op[])(struct file *, char *, size_t) = {
866 [SEL_ACCESS] = sel_write_access,
867 [SEL_CREATE] = sel_write_create,
868 [SEL_RELABEL] = sel_write_relabel,
869 [SEL_USER] = sel_write_user,
870 [SEL_MEMBER] = sel_write_member,
871 [SEL_CONTEXT] = sel_write_context,
872};
873
874static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
875{
876 ino_t ino = file_inode(file)->i_ino;
877 char *data;
878 ssize_t rv;
879
880 if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
881 return -EINVAL;
882
883 data = simple_transaction_get(file, buf, size);
884 if (IS_ERR(data))
885 return PTR_ERR(data);
886
887 rv = write_op[ino](file, data, size);
888 if (rv > 0) {
889 simple_transaction_set(file, rv);
890 rv = size;
891 }
892 return rv;
893}
894
895static const struct file_operations transaction_ops = {
896 .write = selinux_transaction_write,
897 .read = simple_transaction_read,
898 .release = simple_transaction_release,
899 .llseek = generic_file_llseek,
900};
901
902/*
903 * payload - write methods
904 * If the method has a response, the response should be put in buf,
905 * and the length returned. Otherwise return 0 or and -error.
906 */
907
908static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
909{
910 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
911 struct selinux_state *state = fsi->state;
912 char *scon = NULL, *tcon = NULL;
913 u32 ssid, tsid;
914 u16 tclass;
915 struct av_decision avd;
916 ssize_t length;
917
918 length = avc_has_perm(&selinux_state,
919 current_sid(), SECINITSID_SECURITY,
920 SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
921 if (length)
922 goto out;
923
924 length = -ENOMEM;
925 scon = kzalloc(size + 1, GFP_KERNEL);
926 if (!scon)
927 goto out;
928
929 length = -ENOMEM;
930 tcon = kzalloc(size + 1, GFP_KERNEL);
931 if (!tcon)
932 goto out;
933
934 length = -EINVAL;
935 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
936 goto out;
937
938 length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
939 if (length)
940 goto out;
941
942 length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
943 if (length)
944 goto out;
945
946 security_compute_av_user(state, ssid, tsid, tclass, &avd);
947
948 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
949 "%x %x %x %x %u %x",
950 avd.allowed, 0xffffffff,
951 avd.auditallow, avd.auditdeny,
952 avd.seqno, avd.flags);
953out:
954 kfree(tcon);
955 kfree(scon);
956 return length;
957}
958
959static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
960{
961 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
962 struct selinux_state *state = fsi->state;
963 char *scon = NULL, *tcon = NULL;
964 char *namebuf = NULL, *objname = NULL;
965 u32 ssid, tsid, newsid;
966 u16 tclass;
967 ssize_t length;
968 char *newcon = NULL;
969 u32 len;
970 int nargs;
971
972 length = avc_has_perm(&selinux_state,
973 current_sid(), SECINITSID_SECURITY,
974 SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
975 NULL);
976 if (length)
977 goto out;
978
979 length = -ENOMEM;
980 scon = kzalloc(size + 1, GFP_KERNEL);
981 if (!scon)
982 goto out;
983
984 length = -ENOMEM;
985 tcon = kzalloc(size + 1, GFP_KERNEL);
986 if (!tcon)
987 goto out;
988
989 length = -ENOMEM;
990 namebuf = kzalloc(size + 1, GFP_KERNEL);
991 if (!namebuf)
992 goto out;
993
994 length = -EINVAL;
995 nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
996 if (nargs < 3 || nargs > 4)
997 goto out;
998 if (nargs == 4) {
999 /*
1000 * If and when the name of new object to be queried contains
1001 * either whitespace or multibyte characters, they shall be
1002 * encoded based on the percentage-encoding rule.
1003 * If not encoded, the sscanf logic picks up only left-half
1004 * of the supplied name; splitted by a whitespace unexpectedly.
1005 */
1006 char *r, *w;
1007 int c1, c2;
1008
1009 r = w = namebuf;
1010 do {
1011 c1 = *r++;
1012 if (c1 == '+')
1013 c1 = ' ';
1014 else if (c1 == '%') {
1015 c1 = hex_to_bin(*r++);
1016 if (c1 < 0)
1017 goto out;
1018 c2 = hex_to_bin(*r++);
1019 if (c2 < 0)
1020 goto out;
1021 c1 = (c1 << 4) | c2;
1022 }
1023 *w++ = c1;
1024 } while (c1 != '\0');
1025
1026 objname = namebuf;
1027 }
1028
1029 length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
1030 if (length)
1031 goto out;
1032
1033 length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1034 if (length)
1035 goto out;
1036
1037 length = security_transition_sid_user(state, ssid, tsid, tclass,
1038 objname, &newsid);
1039 if (length)
1040 goto out;
1041
1042 length = security_sid_to_context(state, newsid, &newcon, &len);
1043 if (length)
1044 goto out;
1045
1046 length = -ERANGE;
1047 if (len > SIMPLE_TRANSACTION_LIMIT) {
1048 pr_err("SELinux: %s: context size (%u) exceeds "
1049 "payload max\n", __func__, len);
1050 goto out;
1051 }
1052
1053 memcpy(buf, newcon, len);
1054 length = len;
1055out:
1056 kfree(newcon);
1057 kfree(namebuf);
1058 kfree(tcon);
1059 kfree(scon);
1060 return length;
1061}
1062
1063static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
1064{
1065 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1066 struct selinux_state *state = fsi->state;
1067 char *scon = NULL, *tcon = NULL;
1068 u32 ssid, tsid, newsid;
1069 u16 tclass;
1070 ssize_t length;
1071 char *newcon = NULL;
1072 u32 len;
1073
1074 length = avc_has_perm(&selinux_state,
1075 current_sid(), SECINITSID_SECURITY,
1076 SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
1077 NULL);
1078 if (length)
1079 goto out;
1080
1081 length = -ENOMEM;
1082 scon = kzalloc(size + 1, GFP_KERNEL);
1083 if (!scon)
1084 goto out;
1085
1086 length = -ENOMEM;
1087 tcon = kzalloc(size + 1, GFP_KERNEL);
1088 if (!tcon)
1089 goto out;
1090
1091 length = -EINVAL;
1092 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1093 goto out;
1094
1095 length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
1096 if (length)
1097 goto out;
1098
1099 length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1100 if (length)
1101 goto out;
1102
1103 length = security_change_sid(state, ssid, tsid, tclass, &newsid);
1104 if (length)
1105 goto out;
1106
1107 length = security_sid_to_context(state, newsid, &newcon, &len);
1108 if (length)
1109 goto out;
1110
1111 length = -ERANGE;
1112 if (len > SIMPLE_TRANSACTION_LIMIT)
1113 goto out;
1114
1115 memcpy(buf, newcon, len);
1116 length = len;
1117out:
1118 kfree(newcon);
1119 kfree(tcon);
1120 kfree(scon);
1121 return length;
1122}
1123
1124static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
1125{
1126 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1127 struct selinux_state *state = fsi->state;
1128 char *con = NULL, *user = NULL, *ptr;
1129 u32 sid, *sids = NULL;
1130 ssize_t length;
1131 char *newcon;
1132 int i, rc;
1133 u32 len, nsids;
1134
1135 length = avc_has_perm(&selinux_state,
1136 current_sid(), SECINITSID_SECURITY,
1137 SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
1138 NULL);
1139 if (length)
1140 goto out;
1141
1142 length = -ENOMEM;
1143 con = kzalloc(size + 1, GFP_KERNEL);
1144 if (!con)
1145 goto out;
1146
1147 length = -ENOMEM;
1148 user = kzalloc(size + 1, GFP_KERNEL);
1149 if (!user)
1150 goto out;
1151
1152 length = -EINVAL;
1153 if (sscanf(buf, "%s %s", con, user) != 2)
1154 goto out;
1155
1156 length = security_context_str_to_sid(state, con, &sid, GFP_KERNEL);
1157 if (length)
1158 goto out;
1159
1160 length = security_get_user_sids(state, sid, user, &sids, &nsids);
1161 if (length)
1162 goto out;
1163
1164 length = sprintf(buf, "%u", nsids) + 1;
1165 ptr = buf + length;
1166 for (i = 0; i < nsids; i++) {
1167 rc = security_sid_to_context(state, sids[i], &newcon, &len);
1168 if (rc) {
1169 length = rc;
1170 goto out;
1171 }
1172 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1173 kfree(newcon);
1174 length = -ERANGE;
1175 goto out;
1176 }
1177 memcpy(ptr, newcon, len);
1178 kfree(newcon);
1179 ptr += len;
1180 length += len;
1181 }
1182out:
1183 kfree(sids);
1184 kfree(user);
1185 kfree(con);
1186 return length;
1187}
1188
1189static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1190{
1191 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1192 struct selinux_state *state = fsi->state;
1193 char *scon = NULL, *tcon = NULL;
1194 u32 ssid, tsid, newsid;
1195 u16 tclass;
1196 ssize_t length;
1197 char *newcon = NULL;
1198 u32 len;
1199
1200 length = avc_has_perm(&selinux_state,
1201 current_sid(), SECINITSID_SECURITY,
1202 SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
1203 NULL);
1204 if (length)
1205 goto out;
1206
1207 length = -ENOMEM;
1208 scon = kzalloc(size + 1, GFP_KERNEL);
1209 if (!scon)
1210 goto out;
1211
1212 length = -ENOMEM;
1213 tcon = kzalloc(size + 1, GFP_KERNEL);
1214 if (!tcon)
1215 goto out;
1216
1217 length = -EINVAL;
1218 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1219 goto out;
1220
1221 length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
1222 if (length)
1223 goto out;
1224
1225 length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1226 if (length)
1227 goto out;
1228
1229 length = security_member_sid(state, ssid, tsid, tclass, &newsid);
1230 if (length)
1231 goto out;
1232
1233 length = security_sid_to_context(state, newsid, &newcon, &len);
1234 if (length)
1235 goto out;
1236
1237 length = -ERANGE;
1238 if (len > SIMPLE_TRANSACTION_LIMIT) {
1239 pr_err("SELinux: %s: context size (%u) exceeds "
1240 "payload max\n", __func__, len);
1241 goto out;
1242 }
1243
1244 memcpy(buf, newcon, len);
1245 length = len;
1246out:
1247 kfree(newcon);
1248 kfree(tcon);
1249 kfree(scon);
1250 return length;
1251}
1252
1253static struct inode *sel_make_inode(struct super_block *sb, int mode)
1254{
1255 struct inode *ret = new_inode(sb);
1256
1257 if (ret) {
1258 ret->i_mode = mode;
1259 ret->i_atime = ret->i_mtime = ret->i_ctime = current_time(ret);
1260 }
1261 return ret;
1262}
1263
1264static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1265 size_t count, loff_t *ppos)
1266{
1267 struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1268 char *page = NULL;
1269 ssize_t length;
1270 ssize_t ret;
1271 int cur_enforcing;
1272 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1273 const char *name = filep->f_path.dentry->d_name.name;
1274
1275 mutex_lock(&fsi->state->policy_mutex);
1276
1277 ret = -EINVAL;
1278 if (index >= fsi->bool_num || strcmp(name,
1279 fsi->bool_pending_names[index]))
1280 goto out_unlock;
1281
1282 ret = -ENOMEM;
1283 page = (char *)get_zeroed_page(GFP_KERNEL);
1284 if (!page)
1285 goto out_unlock;
1286
1287 cur_enforcing = security_get_bool_value(fsi->state, index);
1288 if (cur_enforcing < 0) {
1289 ret = cur_enforcing;
1290 goto out_unlock;
1291 }
1292 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1293 fsi->bool_pending_values[index]);
1294 mutex_unlock(&fsi->state->policy_mutex);
1295 ret = simple_read_from_buffer(buf, count, ppos, page, length);
1296out_free:
1297 free_page((unsigned long)page);
1298 return ret;
1299
1300out_unlock:
1301 mutex_unlock(&fsi->state->policy_mutex);
1302 goto out_free;
1303}
1304
1305static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1306 size_t count, loff_t *ppos)
1307{
1308 struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1309 char *page = NULL;
1310 ssize_t length;
1311 int new_value;
1312 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1313 const char *name = filep->f_path.dentry->d_name.name;
1314
1315 if (count >= PAGE_SIZE)
1316 return -ENOMEM;
1317
1318 /* No partial writes. */
1319 if (*ppos != 0)
1320 return -EINVAL;
1321
1322 page = memdup_user_nul(buf, count);
1323 if (IS_ERR(page))
1324 return PTR_ERR(page);
1325
1326 mutex_lock(&fsi->state->policy_mutex);
1327
1328 length = avc_has_perm(&selinux_state,
1329 current_sid(), SECINITSID_SECURITY,
1330 SECCLASS_SECURITY, SECURITY__SETBOOL,
1331 NULL);
1332 if (length)
1333 goto out;
1334
1335 length = -EINVAL;
1336 if (index >= fsi->bool_num || strcmp(name,
1337 fsi->bool_pending_names[index]))
1338 goto out;
1339
1340 length = -EINVAL;
1341 if (sscanf(page, "%d", &new_value) != 1)
1342 goto out;
1343
1344 if (new_value)
1345 new_value = 1;
1346
1347 fsi->bool_pending_values[index] = new_value;
1348 length = count;
1349
1350out:
1351 mutex_unlock(&fsi->state->policy_mutex);
1352 kfree(page);
1353 return length;
1354}
1355
1356static const struct file_operations sel_bool_ops = {
1357 .read = sel_read_bool,
1358 .write = sel_write_bool,
1359 .llseek = generic_file_llseek,
1360};
1361
1362static ssize_t sel_commit_bools_write(struct file *filep,
1363 const char __user *buf,
1364 size_t count, loff_t *ppos)
1365{
1366 struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1367 char *page = NULL;
1368 ssize_t length;
1369 int new_value;
1370
1371 if (count >= PAGE_SIZE)
1372 return -ENOMEM;
1373
1374 /* No partial writes. */
1375 if (*ppos != 0)
1376 return -EINVAL;
1377
1378 page = memdup_user_nul(buf, count);
1379 if (IS_ERR(page))
1380 return PTR_ERR(page);
1381
1382 mutex_lock(&fsi->state->policy_mutex);
1383
1384 length = avc_has_perm(&selinux_state,
1385 current_sid(), SECINITSID_SECURITY,
1386 SECCLASS_SECURITY, SECURITY__SETBOOL,
1387 NULL);
1388 if (length)
1389 goto out;
1390
1391 length = -EINVAL;
1392 if (sscanf(page, "%d", &new_value) != 1)
1393 goto out;
1394
1395 length = 0;
1396 if (new_value && fsi->bool_pending_values)
1397 length = security_set_bools(fsi->state, fsi->bool_num,
1398 fsi->bool_pending_values);
1399
1400 if (!length)
1401 length = count;
1402
1403out:
1404 mutex_unlock(&fsi->state->policy_mutex);
1405 kfree(page);
1406 return length;
1407}
1408
1409static const struct file_operations sel_commit_bools_ops = {
1410 .write = sel_commit_bools_write,
1411 .llseek = generic_file_llseek,
1412};
1413
1414static void sel_remove_entries(struct dentry *de)
1415{
1416 d_genocide(de);
1417 shrink_dcache_parent(de);
1418}
1419
1420static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
1421 unsigned int *bool_num, char ***bool_pending_names,
1422 unsigned int **bool_pending_values)
1423{
1424 int ret;
1425 ssize_t len;
1426 struct dentry *dentry = NULL;
1427 struct inode *inode = NULL;
1428 struct inode_security_struct *isec;
1429 char **names = NULL, *page;
1430 u32 i, num;
1431 int *values = NULL;
1432 u32 sid;
1433
1434 ret = -ENOMEM;
1435 page = (char *)get_zeroed_page(GFP_KERNEL);
1436 if (!page)
1437 goto out;
1438
1439 ret = security_get_bools(newpolicy, &num, &names, &values);
1440 if (ret)
1441 goto out;
1442
1443 for (i = 0; i < num; i++) {
1444 ret = -ENOMEM;
1445 dentry = d_alloc_name(bool_dir, names[i]);
1446 if (!dentry)
1447 goto out;
1448
1449 ret = -ENOMEM;
1450 inode = sel_make_inode(bool_dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1451 if (!inode) {
1452 dput(dentry);
1453 goto out;
1454 }
1455
1456 ret = -ENAMETOOLONG;
1457 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1458 if (len >= PAGE_SIZE) {
1459 dput(dentry);
1460 iput(inode);
1461 goto out;
1462 }
1463
1464 isec = selinux_inode(inode);
1465 ret = selinux_policy_genfs_sid(newpolicy, "selinuxfs", page,
1466 SECCLASS_FILE, &sid);
1467 if (ret) {
1468 pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
1469 page);
1470 sid = SECINITSID_SECURITY;
1471 }
1472
1473 isec->sid = sid;
1474 isec->initialized = LABEL_INITIALIZED;
1475 inode->i_fop = &sel_bool_ops;
1476 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1477 d_add(dentry, inode);
1478 }
1479 *bool_num = num;
1480 *bool_pending_names = names;
1481 *bool_pending_values = values;
1482
1483 free_page((unsigned long)page);
1484 return 0;
1485out:
1486 free_page((unsigned long)page);
1487
1488 if (names) {
1489 for (i = 0; i < num; i++)
1490 kfree(names[i]);
1491 kfree(names);
1492 }
1493 kfree(values);
1494 sel_remove_entries(bool_dir);
1495
1496 return ret;
1497}
1498
1499static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1500 size_t count, loff_t *ppos)
1501{
1502 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1503 struct selinux_state *state = fsi->state;
1504 char tmpbuf[TMPBUFLEN];
1505 ssize_t length;
1506
1507 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1508 avc_get_cache_threshold(state->avc));
1509 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1510}
1511
1512static ssize_t sel_write_avc_cache_threshold(struct file *file,
1513 const char __user *buf,
1514 size_t count, loff_t *ppos)
1515
1516{
1517 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1518 struct selinux_state *state = fsi->state;
1519 char *page;
1520 ssize_t ret;
1521 unsigned int new_value;
1522
1523 ret = avc_has_perm(&selinux_state,
1524 current_sid(), SECINITSID_SECURITY,
1525 SECCLASS_SECURITY, SECURITY__SETSECPARAM,
1526 NULL);
1527 if (ret)
1528 return ret;
1529
1530 if (count >= PAGE_SIZE)
1531 return -ENOMEM;
1532
1533 /* No partial writes. */
1534 if (*ppos != 0)
1535 return -EINVAL;
1536
1537 page = memdup_user_nul(buf, count);
1538 if (IS_ERR(page))
1539 return PTR_ERR(page);
1540
1541 ret = -EINVAL;
1542 if (sscanf(page, "%u", &new_value) != 1)
1543 goto out;
1544
1545 avc_set_cache_threshold(state->avc, new_value);
1546
1547 ret = count;
1548out:
1549 kfree(page);
1550 return ret;
1551}
1552
1553static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1554 size_t count, loff_t *ppos)
1555{
1556 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1557 struct selinux_state *state = fsi->state;
1558 char *page;
1559 ssize_t length;
1560
1561 page = (char *)__get_free_page(GFP_KERNEL);
1562 if (!page)
1563 return -ENOMEM;
1564
1565 length = avc_get_hash_stats(state->avc, page);
1566 if (length >= 0)
1567 length = simple_read_from_buffer(buf, count, ppos, page, length);
1568 free_page((unsigned long)page);
1569
1570 return length;
1571}
1572
1573static ssize_t sel_read_sidtab_hash_stats(struct file *filp, char __user *buf,
1574 size_t count, loff_t *ppos)
1575{
1576 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1577 struct selinux_state *state = fsi->state;
1578 char *page;
1579 ssize_t length;
1580
1581 page = (char *)__get_free_page(GFP_KERNEL);
1582 if (!page)
1583 return -ENOMEM;
1584
1585 length = security_sidtab_hash_stats(state, page);
1586 if (length >= 0)
1587 length = simple_read_from_buffer(buf, count, ppos, page,
1588 length);
1589 free_page((unsigned long)page);
1590
1591 return length;
1592}
1593
1594static const struct file_operations sel_sidtab_hash_stats_ops = {
1595 .read = sel_read_sidtab_hash_stats,
1596 .llseek = generic_file_llseek,
1597};
1598
1599static const struct file_operations sel_avc_cache_threshold_ops = {
1600 .read = sel_read_avc_cache_threshold,
1601 .write = sel_write_avc_cache_threshold,
1602 .llseek = generic_file_llseek,
1603};
1604
1605static const struct file_operations sel_avc_hash_stats_ops = {
1606 .read = sel_read_avc_hash_stats,
1607 .llseek = generic_file_llseek,
1608};
1609
1610#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1611static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1612{
1613 int cpu;
1614
1615 for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1616 if (!cpu_possible(cpu))
1617 continue;
1618 *idx = cpu + 1;
1619 return &per_cpu(avc_cache_stats, cpu);
1620 }
1621 (*idx)++;
1622 return NULL;
1623}
1624
1625static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1626{
1627 loff_t n = *pos - 1;
1628
1629 if (*pos == 0)
1630 return SEQ_START_TOKEN;
1631
1632 return sel_avc_get_stat_idx(&n);
1633}
1634
1635static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1636{
1637 return sel_avc_get_stat_idx(pos);
1638}
1639
1640static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1641{
1642 struct avc_cache_stats *st = v;
1643
1644 if (v == SEQ_START_TOKEN) {
1645 seq_puts(seq,
1646 "lookups hits misses allocations reclaims frees\n");
1647 } else {
1648 unsigned int lookups = st->lookups;
1649 unsigned int misses = st->misses;
1650 unsigned int hits = lookups - misses;
1651 seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1652 hits, misses, st->allocations,
1653 st->reclaims, st->frees);
1654 }
1655 return 0;
1656}
1657
1658static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1659{ }
1660
1661static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1662 .start = sel_avc_stats_seq_start,
1663 .next = sel_avc_stats_seq_next,
1664 .show = sel_avc_stats_seq_show,
1665 .stop = sel_avc_stats_seq_stop,
1666};
1667
1668static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1669{
1670 return seq_open(file, &sel_avc_cache_stats_seq_ops);
1671}
1672
1673static const struct file_operations sel_avc_cache_stats_ops = {
1674 .open = sel_open_avc_cache_stats,
1675 .read = seq_read,
1676 .llseek = seq_lseek,
1677 .release = seq_release,
1678};
1679#endif
1680
1681static int sel_make_avc_files(struct dentry *dir)
1682{
1683 struct super_block *sb = dir->d_sb;
1684 struct selinux_fs_info *fsi = sb->s_fs_info;
1685 int i;
1686 static const struct tree_descr files[] = {
1687 { "cache_threshold",
1688 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1689 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1690#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1691 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1692#endif
1693 };
1694
1695 for (i = 0; i < ARRAY_SIZE(files); i++) {
1696 struct inode *inode;
1697 struct dentry *dentry;
1698
1699 dentry = d_alloc_name(dir, files[i].name);
1700 if (!dentry)
1701 return -ENOMEM;
1702
1703 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1704 if (!inode) {
1705 dput(dentry);
1706 return -ENOMEM;
1707 }
1708
1709 inode->i_fop = files[i].ops;
1710 inode->i_ino = ++fsi->last_ino;
1711 d_add(dentry, inode);
1712 }
1713
1714 return 0;
1715}
1716
1717static int sel_make_ss_files(struct dentry *dir)
1718{
1719 struct super_block *sb = dir->d_sb;
1720 struct selinux_fs_info *fsi = sb->s_fs_info;
1721 int i;
1722 static struct tree_descr files[] = {
1723 { "sidtab_hash_stats", &sel_sidtab_hash_stats_ops, S_IRUGO },
1724 };
1725
1726 for (i = 0; i < ARRAY_SIZE(files); i++) {
1727 struct inode *inode;
1728 struct dentry *dentry;
1729
1730 dentry = d_alloc_name(dir, files[i].name);
1731 if (!dentry)
1732 return -ENOMEM;
1733
1734 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1735 if (!inode) {
1736 dput(dentry);
1737 return -ENOMEM;
1738 }
1739
1740 inode->i_fop = files[i].ops;
1741 inode->i_ino = ++fsi->last_ino;
1742 d_add(dentry, inode);
1743 }
1744
1745 return 0;
1746}
1747
1748static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1749 size_t count, loff_t *ppos)
1750{
1751 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1752 char *con;
1753 u32 sid, len;
1754 ssize_t ret;
1755
1756 sid = file_inode(file)->i_ino&SEL_INO_MASK;
1757 ret = security_sid_to_context(fsi->state, sid, &con, &len);
1758 if (ret)
1759 return ret;
1760
1761 ret = simple_read_from_buffer(buf, count, ppos, con, len);
1762 kfree(con);
1763 return ret;
1764}
1765
1766static const struct file_operations sel_initcon_ops = {
1767 .read = sel_read_initcon,
1768 .llseek = generic_file_llseek,
1769};
1770
1771static int sel_make_initcon_files(struct dentry *dir)
1772{
1773 int i;
1774
1775 for (i = 1; i <= SECINITSID_NUM; i++) {
1776 struct inode *inode;
1777 struct dentry *dentry;
1778 const char *s = security_get_initial_sid_context(i);
1779
1780 if (!s)
1781 continue;
1782 dentry = d_alloc_name(dir, s);
1783 if (!dentry)
1784 return -ENOMEM;
1785
1786 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1787 if (!inode) {
1788 dput(dentry);
1789 return -ENOMEM;
1790 }
1791
1792 inode->i_fop = &sel_initcon_ops;
1793 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1794 d_add(dentry, inode);
1795 }
1796
1797 return 0;
1798}
1799
1800static inline unsigned long sel_class_to_ino(u16 class)
1801{
1802 return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1803}
1804
1805static inline u16 sel_ino_to_class(unsigned long ino)
1806{
1807 return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1808}
1809
1810static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1811{
1812 return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1813}
1814
1815static inline u32 sel_ino_to_perm(unsigned long ino)
1816{
1817 return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1818}
1819
1820static ssize_t sel_read_class(struct file *file, char __user *buf,
1821 size_t count, loff_t *ppos)
1822{
1823 unsigned long ino = file_inode(file)->i_ino;
1824 char res[TMPBUFLEN];
1825 ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1826 return simple_read_from_buffer(buf, count, ppos, res, len);
1827}
1828
1829static const struct file_operations sel_class_ops = {
1830 .read = sel_read_class,
1831 .llseek = generic_file_llseek,
1832};
1833
1834static ssize_t sel_read_perm(struct file *file, char __user *buf,
1835 size_t count, loff_t *ppos)
1836{
1837 unsigned long ino = file_inode(file)->i_ino;
1838 char res[TMPBUFLEN];
1839 ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1840 return simple_read_from_buffer(buf, count, ppos, res, len);
1841}
1842
1843static const struct file_operations sel_perm_ops = {
1844 .read = sel_read_perm,
1845 .llseek = generic_file_llseek,
1846};
1847
1848static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1849 size_t count, loff_t *ppos)
1850{
1851 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1852 int value;
1853 char tmpbuf[TMPBUFLEN];
1854 ssize_t length;
1855 unsigned long i_ino = file_inode(file)->i_ino;
1856
1857 value = security_policycap_supported(fsi->state, i_ino & SEL_INO_MASK);
1858 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1859
1860 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1861}
1862
1863static const struct file_operations sel_policycap_ops = {
1864 .read = sel_read_policycap,
1865 .llseek = generic_file_llseek,
1866};
1867
1868static int sel_make_perm_files(struct selinux_policy *newpolicy,
1869 char *objclass, int classvalue,
1870 struct dentry *dir)
1871{
1872 int i, rc, nperms;
1873 char **perms;
1874
1875 rc = security_get_permissions(newpolicy, objclass, &perms, &nperms);
1876 if (rc)
1877 return rc;
1878
1879 for (i = 0; i < nperms; i++) {
1880 struct inode *inode;
1881 struct dentry *dentry;
1882
1883 rc = -ENOMEM;
1884 dentry = d_alloc_name(dir, perms[i]);
1885 if (!dentry)
1886 goto out;
1887
1888 rc = -ENOMEM;
1889 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1890 if (!inode) {
1891 dput(dentry);
1892 goto out;
1893 }
1894
1895 inode->i_fop = &sel_perm_ops;
1896 /* i+1 since perm values are 1-indexed */
1897 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1898 d_add(dentry, inode);
1899 }
1900 rc = 0;
1901out:
1902 for (i = 0; i < nperms; i++)
1903 kfree(perms[i]);
1904 kfree(perms);
1905 return rc;
1906}
1907
1908static int sel_make_class_dir_entries(struct selinux_policy *newpolicy,
1909 char *classname, int index,
1910 struct dentry *dir)
1911{
1912 struct super_block *sb = dir->d_sb;
1913 struct selinux_fs_info *fsi = sb->s_fs_info;
1914 struct dentry *dentry = NULL;
1915 struct inode *inode = NULL;
1916 int rc;
1917
1918 dentry = d_alloc_name(dir, "index");
1919 if (!dentry)
1920 return -ENOMEM;
1921
1922 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1923 if (!inode) {
1924 dput(dentry);
1925 return -ENOMEM;
1926 }
1927
1928 inode->i_fop = &sel_class_ops;
1929 inode->i_ino = sel_class_to_ino(index);
1930 d_add(dentry, inode);
1931
1932 dentry = sel_make_dir(dir, "perms", &fsi->last_class_ino);
1933 if (IS_ERR(dentry))
1934 return PTR_ERR(dentry);
1935
1936 rc = sel_make_perm_files(newpolicy, classname, index, dentry);
1937
1938 return rc;
1939}
1940
1941static int sel_make_classes(struct selinux_policy *newpolicy,
1942 struct dentry *class_dir,
1943 unsigned long *last_class_ino)
1944{
1945
1946 int rc, nclasses, i;
1947 char **classes;
1948
1949 rc = security_get_classes(newpolicy, &classes, &nclasses);
1950 if (rc)
1951 return rc;
1952
1953 /* +2 since classes are 1-indexed */
1954 *last_class_ino = sel_class_to_ino(nclasses + 2);
1955
1956 for (i = 0; i < nclasses; i++) {
1957 struct dentry *class_name_dir;
1958
1959 class_name_dir = sel_make_dir(class_dir, classes[i],
1960 last_class_ino);
1961 if (IS_ERR(class_name_dir)) {
1962 rc = PTR_ERR(class_name_dir);
1963 goto out;
1964 }
1965
1966 /* i+1 since class values are 1-indexed */
1967 rc = sel_make_class_dir_entries(newpolicy, classes[i], i + 1,
1968 class_name_dir);
1969 if (rc)
1970 goto out;
1971 }
1972 rc = 0;
1973out:
1974 for (i = 0; i < nclasses; i++)
1975 kfree(classes[i]);
1976 kfree(classes);
1977 return rc;
1978}
1979
1980static int sel_make_policycap(struct selinux_fs_info *fsi)
1981{
1982 unsigned int iter;
1983 struct dentry *dentry = NULL;
1984 struct inode *inode = NULL;
1985
1986 for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1987 if (iter < ARRAY_SIZE(selinux_policycap_names))
1988 dentry = d_alloc_name(fsi->policycap_dir,
1989 selinux_policycap_names[iter]);
1990 else
1991 dentry = d_alloc_name(fsi->policycap_dir, "unknown");
1992
1993 if (dentry == NULL)
1994 return -ENOMEM;
1995
1996 inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
1997 if (inode == NULL) {
1998 dput(dentry);
1999 return -ENOMEM;
2000 }
2001
2002 inode->i_fop = &sel_policycap_ops;
2003 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
2004 d_add(dentry, inode);
2005 }
2006
2007 return 0;
2008}
2009
2010static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
2011 unsigned long *ino)
2012{
2013 struct dentry *dentry = d_alloc_name(dir, name);
2014 struct inode *inode;
2015
2016 if (!dentry)
2017 return ERR_PTR(-ENOMEM);
2018
2019 inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
2020 if (!inode) {
2021 dput(dentry);
2022 return ERR_PTR(-ENOMEM);
2023 }
2024
2025 inode->i_op = &simple_dir_inode_operations;
2026 inode->i_fop = &simple_dir_operations;
2027 inode->i_ino = ++(*ino);
2028 /* directory inodes start off with i_nlink == 2 (for "." entry) */
2029 inc_nlink(inode);
2030 d_add(dentry, inode);
2031 /* bump link count on parent directory, too */
2032 inc_nlink(d_inode(dir));
2033
2034 return dentry;
2035}
2036
2037static struct dentry *sel_make_disconnected_dir(struct super_block *sb,
2038 unsigned long *ino)
2039{
2040 struct inode *inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
2041
2042 if (!inode)
2043 return ERR_PTR(-ENOMEM);
2044
2045 inode->i_op = &simple_dir_inode_operations;
2046 inode->i_fop = &simple_dir_operations;
2047 inode->i_ino = ++(*ino);
2048 /* directory inodes start off with i_nlink == 2 (for "." entry) */
2049 inc_nlink(inode);
2050 return d_obtain_alias(inode);
2051}
2052
2053#define NULL_FILE_NAME "null"
2054
2055static int sel_fill_super(struct super_block *sb, struct fs_context *fc)
2056{
2057 struct selinux_fs_info *fsi;
2058 int ret;
2059 struct dentry *dentry;
2060 struct inode *inode;
2061 struct inode_security_struct *isec;
2062
2063 static const struct tree_descr selinux_files[] = {
2064 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
2065 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
2066 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
2067 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
2068 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
2069 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
2070 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
2071 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
2072 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
2073 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
2074 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
2075 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
2076 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
2077 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
2078 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
2079 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
2080 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
2081 [SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
2082 S_IWUGO},
2083 /* last one */ {""}
2084 };
2085
2086 ret = selinux_fs_info_create(sb);
2087 if (ret)
2088 goto err;
2089
2090 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
2091 if (ret)
2092 goto err;
2093
2094 fsi = sb->s_fs_info;
2095 fsi->bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &fsi->last_ino);
2096 if (IS_ERR(fsi->bool_dir)) {
2097 ret = PTR_ERR(fsi->bool_dir);
2098 fsi->bool_dir = NULL;
2099 goto err;
2100 }
2101
2102 ret = -ENOMEM;
2103 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
2104 if (!dentry)
2105 goto err;
2106
2107 ret = -ENOMEM;
2108 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
2109 if (!inode) {
2110 dput(dentry);
2111 goto err;
2112 }
2113
2114 inode->i_ino = ++fsi->last_ino;
2115 isec = selinux_inode(inode);
2116 isec->sid = SECINITSID_DEVNULL;
2117 isec->sclass = SECCLASS_CHR_FILE;
2118 isec->initialized = LABEL_INITIALIZED;
2119
2120 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
2121 d_add(dentry, inode);
2122
2123 dentry = sel_make_dir(sb->s_root, "avc", &fsi->last_ino);
2124 if (IS_ERR(dentry)) {
2125 ret = PTR_ERR(dentry);
2126 goto err;
2127 }
2128
2129 ret = sel_make_avc_files(dentry);
2130
2131 dentry = sel_make_dir(sb->s_root, "ss", &fsi->last_ino);
2132 if (IS_ERR(dentry)) {
2133 ret = PTR_ERR(dentry);
2134 goto err;
2135 }
2136
2137 ret = sel_make_ss_files(dentry);
2138 if (ret)
2139 goto err;
2140
2141 dentry = sel_make_dir(sb->s_root, "initial_contexts", &fsi->last_ino);
2142 if (IS_ERR(dentry)) {
2143 ret = PTR_ERR(dentry);
2144 goto err;
2145 }
2146
2147 ret = sel_make_initcon_files(dentry);
2148 if (ret)
2149 goto err;
2150
2151 fsi->class_dir = sel_make_dir(sb->s_root, CLASS_DIR_NAME, &fsi->last_ino);
2152 if (IS_ERR(fsi->class_dir)) {
2153 ret = PTR_ERR(fsi->class_dir);
2154 fsi->class_dir = NULL;
2155 goto err;
2156 }
2157
2158 fsi->policycap_dir = sel_make_dir(sb->s_root, POLICYCAP_DIR_NAME,
2159 &fsi->last_ino);
2160 if (IS_ERR(fsi->policycap_dir)) {
2161 ret = PTR_ERR(fsi->policycap_dir);
2162 fsi->policycap_dir = NULL;
2163 goto err;
2164 }
2165
2166 ret = sel_make_policycap(fsi);
2167 if (ret) {
2168 pr_err("SELinux: failed to load policy capabilities\n");
2169 goto err;
2170 }
2171
2172 return 0;
2173err:
2174 pr_err("SELinux: %s: failed while creating inodes\n",
2175 __func__);
2176
2177 selinux_fs_info_free(sb);
2178
2179 return ret;
2180}
2181
2182static int sel_get_tree(struct fs_context *fc)
2183{
2184 return get_tree_single(fc, sel_fill_super);
2185}
2186
2187static const struct fs_context_operations sel_context_ops = {
2188 .get_tree = sel_get_tree,
2189};
2190
2191static int sel_init_fs_context(struct fs_context *fc)
2192{
2193 fc->ops = &sel_context_ops;
2194 return 0;
2195}
2196
2197static void sel_kill_sb(struct super_block *sb)
2198{
2199 selinux_fs_info_free(sb);
2200 kill_litter_super(sb);
2201}
2202
2203static struct file_system_type sel_fs_type = {
2204 .name = "selinuxfs",
2205 .init_fs_context = sel_init_fs_context,
2206 .kill_sb = sel_kill_sb,
2207};
2208
2209static struct vfsmount *selinuxfs_mount __ro_after_init;
2210struct path selinux_null __ro_after_init;
2211
2212static int __init init_sel_fs(void)
2213{
2214 struct qstr null_name = QSTR_INIT(NULL_FILE_NAME,
2215 sizeof(NULL_FILE_NAME)-1);
2216 int err;
2217
2218 if (!selinux_enabled_boot)
2219 return 0;
2220
2221 err = sysfs_create_mount_point(fs_kobj, "selinux");
2222 if (err)
2223 return err;
2224
2225 err = register_filesystem(&sel_fs_type);
2226 if (err) {
2227 sysfs_remove_mount_point(fs_kobj, "selinux");
2228 return err;
2229 }
2230
2231 selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type);
2232 if (IS_ERR(selinuxfs_mount)) {
2233 pr_err("selinuxfs: could not mount!\n");
2234 err = PTR_ERR(selinuxfs_mount);
2235 selinuxfs_mount = NULL;
2236 }
2237 selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root,
2238 &null_name);
2239 if (IS_ERR(selinux_null.dentry)) {
2240 pr_err("selinuxfs: could not lookup null!\n");
2241 err = PTR_ERR(selinux_null.dentry);
2242 selinux_null.dentry = NULL;
2243 }
2244
2245 return err;
2246}
2247
2248__initcall(init_sel_fs);
2249
2250#ifdef CONFIG_SECURITY_SELINUX_DISABLE
2251void exit_sel_fs(void)
2252{
2253 sysfs_remove_mount_point(fs_kobj, "selinux");
2254 dput(selinux_null.dentry);
2255 kern_unmount(selinuxfs_mount);
2256 unregister_filesystem(&sel_fs_type);
2257}
2258#endif