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
46 enum sel_inos {
47 SEL_ROOT_INO = 2,
48 SEL_LOAD, /* load policy */
49 SEL_ENFORCE, /* get or set enforcing status */
50 SEL_CONTEXT, /* validate context */
51 SEL_ACCESS, /* compute access decision */
52 SEL_CREATE, /* compute create labeling decision */
53 SEL_RELABEL, /* compute relabeling decision */
54 SEL_USER, /* compute reachable user contexts */
55 SEL_POLICYVERS, /* return policy version for this kernel */
56 SEL_COMMIT_BOOLS, /* commit new boolean values */
57 SEL_MLS, /* return if MLS policy is enabled */
58 SEL_DISABLE, /* disable SELinux until next reboot */
59 SEL_MEMBER, /* compute polyinstantiation membership decision */
60 SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
61 SEL_COMPAT_NET, /* whether to use old compat network packet controls */
62 SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
63 SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
64 SEL_STATUS, /* export current status using mmap() */
65 SEL_POLICY, /* allow userspace to read the in kernel policy */
66 SEL_VALIDATE_TRANS, /* compute validatetrans decision */
67 SEL_INO_NEXT, /* The next inode number to use */
68 };
69
70 struct selinux_fs_info {
71 struct dentry *bool_dir;
72 unsigned int bool_num;
73 char **bool_pending_names;
74 int *bool_pending_values;
75 struct dentry *class_dir;
76 unsigned long last_class_ino;
77 bool policy_opened;
78 struct dentry *policycap_dir;
79 unsigned long last_ino;
80 struct super_block *sb;
81 };
82
selinux_fs_info_create(struct super_block * sb)83 static int selinux_fs_info_create(struct super_block *sb)
84 {
85 struct selinux_fs_info *fsi;
86
87 fsi = kzalloc(sizeof(*fsi), GFP_KERNEL);
88 if (!fsi)
89 return -ENOMEM;
90
91 fsi->last_ino = SEL_INO_NEXT - 1;
92 fsi->sb = sb;
93 sb->s_fs_info = fsi;
94 return 0;
95 }
96
selinux_fs_info_free(struct super_block * sb)97 static void selinux_fs_info_free(struct super_block *sb)
98 {
99 struct selinux_fs_info *fsi = sb->s_fs_info;
100 unsigned int i;
101
102 if (fsi) {
103 for (i = 0; i < fsi->bool_num; i++)
104 kfree(fsi->bool_pending_names[i]);
105 kfree(fsi->bool_pending_names);
106 kfree(fsi->bool_pending_values);
107 }
108 kfree(sb->s_fs_info);
109 sb->s_fs_info = NULL;
110 }
111
112 #define SEL_INITCON_INO_OFFSET 0x01000000
113 #define SEL_BOOL_INO_OFFSET 0x02000000
114 #define SEL_CLASS_INO_OFFSET 0x04000000
115 #define SEL_POLICYCAP_INO_OFFSET 0x08000000
116 #define SEL_INO_MASK 0x00ffffff
117
118 #define BOOL_DIR_NAME "booleans"
119 #define CLASS_DIR_NAME "class"
120 #define POLICYCAP_DIR_NAME "policy_capabilities"
121
122 #define TMPBUFLEN 12
sel_read_enforce(struct file * filp,char __user * buf,size_t count,loff_t * ppos)123 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
124 size_t count, loff_t *ppos)
125 {
126 char tmpbuf[TMPBUFLEN];
127 ssize_t length;
128
129 length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
130 enforcing_enabled());
131 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
132 }
133
134 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
sel_write_enforce(struct file * file,const char __user * buf,size_t count,loff_t * ppos)135 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
136 size_t count, loff_t *ppos)
137
138 {
139 char *page = NULL;
140 ssize_t length;
141 int scan_value;
142 bool old_value, new_value;
143
144 if (count >= PAGE_SIZE)
145 return -ENOMEM;
146
147 /* No partial writes. */
148 if (*ppos != 0)
149 return -EINVAL;
150
151 page = memdup_user_nul(buf, count);
152 if (IS_ERR(page))
153 return PTR_ERR(page);
154
155 length = -EINVAL;
156 if (sscanf(page, "%d", &scan_value) != 1)
157 goto out;
158
159 new_value = !!scan_value;
160
161 old_value = enforcing_enabled();
162 if (new_value != old_value) {
163 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
164 SECCLASS_SECURITY, SECURITY__SETENFORCE,
165 NULL);
166 if (length)
167 goto out;
168 audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
169 "enforcing=%d old_enforcing=%d auid=%u ses=%u"
170 " enabled=1 old-enabled=1 lsm=selinux res=1",
171 new_value, old_value,
172 from_kuid(&init_user_ns, audit_get_loginuid(current)),
173 audit_get_sessionid(current));
174 enforcing_set(new_value);
175 if (new_value)
176 avc_ss_reset(0);
177 selnl_notify_setenforce(new_value);
178 selinux_status_update_setenforce(new_value);
179 if (!new_value)
180 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
181
182 selinux_ima_measure_state();
183 }
184 length = count;
185 out:
186 kfree(page);
187 return length;
188 }
189 #else
190 #define sel_write_enforce NULL
191 #endif
192
193 static const struct file_operations sel_enforce_ops = {
194 .read = sel_read_enforce,
195 .write = sel_write_enforce,
196 .llseek = generic_file_llseek,
197 };
198
sel_read_handle_unknown(struct file * filp,char __user * buf,size_t count,loff_t * ppos)199 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
200 size_t count, loff_t *ppos)
201 {
202 char tmpbuf[TMPBUFLEN];
203 ssize_t length;
204 ino_t ino = file_inode(filp)->i_ino;
205 int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
206 security_get_reject_unknown() :
207 !security_get_allow_unknown();
208
209 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
210 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
211 }
212
213 static const struct file_operations sel_handle_unknown_ops = {
214 .read = sel_read_handle_unknown,
215 .llseek = generic_file_llseek,
216 };
217
sel_open_handle_status(struct inode * inode,struct file * filp)218 static int sel_open_handle_status(struct inode *inode, struct file *filp)
219 {
220 struct page *status = selinux_kernel_status_page();
221
222 if (!status)
223 return -ENOMEM;
224
225 filp->private_data = status;
226
227 return 0;
228 }
229
sel_read_handle_status(struct file * filp,char __user * buf,size_t count,loff_t * ppos)230 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
231 size_t count, loff_t *ppos)
232 {
233 struct page *status = filp->private_data;
234
235 BUG_ON(!status);
236
237 return simple_read_from_buffer(buf, count, ppos,
238 page_address(status),
239 sizeof(struct selinux_kernel_status));
240 }
241
sel_mmap_handle_status(struct file * filp,struct vm_area_struct * vma)242 static int sel_mmap_handle_status(struct file *filp,
243 struct vm_area_struct *vma)
244 {
245 struct page *status = filp->private_data;
246 unsigned long size = vma->vm_end - vma->vm_start;
247
248 BUG_ON(!status);
249
250 /* only allows one page from the head */
251 if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
252 return -EIO;
253 /* disallow writable mapping */
254 if (vma->vm_flags & VM_WRITE)
255 return -EPERM;
256 /* disallow mprotect() turns it into writable */
257 vm_flags_clear(vma, VM_MAYWRITE);
258
259 return remap_pfn_range(vma, vma->vm_start,
260 page_to_pfn(status),
261 size, vma->vm_page_prot);
262 }
263
264 static const struct file_operations sel_handle_status_ops = {
265 .open = sel_open_handle_status,
266 .read = sel_read_handle_status,
267 .mmap = sel_mmap_handle_status,
268 .llseek = generic_file_llseek,
269 };
270
sel_write_disable(struct file * file,const char __user * buf,size_t count,loff_t * ppos)271 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
272 size_t count, loff_t *ppos)
273
274 {
275 char *page;
276 ssize_t length;
277 int new_value;
278
279 if (count >= PAGE_SIZE)
280 return -ENOMEM;
281
282 /* No partial writes. */
283 if (*ppos != 0)
284 return -EINVAL;
285
286 page = memdup_user_nul(buf, count);
287 if (IS_ERR(page))
288 return PTR_ERR(page);
289
290 if (sscanf(page, "%d", &new_value) != 1) {
291 length = -EINVAL;
292 goto out;
293 }
294 length = count;
295
296 if (new_value) {
297 pr_err("SELinux: https://github.com/SELinuxProject/selinux-kernel/wiki/DEPRECATE-runtime-disable\n");
298 pr_err("SELinux: Runtime disable is not supported, use selinux=0 on the kernel cmdline.\n");
299 }
300
301 out:
302 kfree(page);
303 return length;
304 }
305
306 static const struct file_operations sel_disable_ops = {
307 .write = sel_write_disable,
308 .llseek = generic_file_llseek,
309 };
310
sel_read_policyvers(struct file * filp,char __user * buf,size_t count,loff_t * ppos)311 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
312 size_t count, loff_t *ppos)
313 {
314 char tmpbuf[TMPBUFLEN];
315 ssize_t length;
316
317 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
318 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
319 }
320
321 static const struct file_operations sel_policyvers_ops = {
322 .read = sel_read_policyvers,
323 .llseek = generic_file_llseek,
324 };
325
326 /* declaration for sel_write_load */
327 static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
328 unsigned int *bool_num, char ***bool_pending_names,
329 int **bool_pending_values);
330 static int sel_make_classes(struct selinux_policy *newpolicy,
331 struct dentry *class_dir,
332 unsigned long *last_class_ino);
333
334 /* declaration for sel_make_class_dirs */
335 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
336 unsigned long *ino);
337
338 /* declaration for sel_make_policy_nodes */
339 static struct dentry *sel_make_swapover_dir(struct super_block *sb,
340 unsigned long *ino);
341
sel_read_mls(struct file * filp,char __user * buf,size_t count,loff_t * ppos)342 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
343 size_t count, loff_t *ppos)
344 {
345 char tmpbuf[TMPBUFLEN];
346 ssize_t length;
347
348 length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
349 security_mls_enabled());
350 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
351 }
352
353 static const struct file_operations sel_mls_ops = {
354 .read = sel_read_mls,
355 .llseek = generic_file_llseek,
356 };
357
358 struct policy_load_memory {
359 size_t len;
360 void *data;
361 };
362
sel_open_policy(struct inode * inode,struct file * filp)363 static int sel_open_policy(struct inode *inode, struct file *filp)
364 {
365 struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
366 struct policy_load_memory *plm = NULL;
367 int rc;
368
369 BUG_ON(filp->private_data);
370
371 mutex_lock(&selinux_state.policy_mutex);
372
373 rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
374 SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
375 if (rc)
376 goto err;
377
378 rc = -EBUSY;
379 if (fsi->policy_opened)
380 goto err;
381
382 rc = -ENOMEM;
383 plm = kzalloc(sizeof(*plm), GFP_KERNEL);
384 if (!plm)
385 goto err;
386
387 rc = security_read_policy(&plm->data, &plm->len);
388 if (rc)
389 goto err;
390
391 if ((size_t)i_size_read(inode) != plm->len) {
392 inode_lock(inode);
393 i_size_write(inode, plm->len);
394 inode_unlock(inode);
395 }
396
397 fsi->policy_opened = 1;
398
399 filp->private_data = plm;
400
401 mutex_unlock(&selinux_state.policy_mutex);
402
403 return 0;
404 err:
405 mutex_unlock(&selinux_state.policy_mutex);
406
407 if (plm)
408 vfree(plm->data);
409 kfree(plm);
410 return rc;
411 }
412
sel_release_policy(struct inode * inode,struct file * filp)413 static int sel_release_policy(struct inode *inode, struct file *filp)
414 {
415 struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
416 struct policy_load_memory *plm = filp->private_data;
417
418 BUG_ON(!plm);
419
420 fsi->policy_opened = 0;
421
422 vfree(plm->data);
423 kfree(plm);
424
425 return 0;
426 }
427
sel_read_policy(struct file * filp,char __user * buf,size_t count,loff_t * ppos)428 static ssize_t sel_read_policy(struct file *filp, char __user *buf,
429 size_t count, loff_t *ppos)
430 {
431 struct policy_load_memory *plm = filp->private_data;
432 int ret;
433
434 ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
435 SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
436 if (ret)
437 return ret;
438
439 return simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
440 }
441
sel_mmap_policy_fault(struct vm_fault * vmf)442 static vm_fault_t sel_mmap_policy_fault(struct vm_fault *vmf)
443 {
444 struct policy_load_memory *plm = vmf->vma->vm_file->private_data;
445 unsigned long offset;
446 struct page *page;
447
448 if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
449 return VM_FAULT_SIGBUS;
450
451 offset = vmf->pgoff << PAGE_SHIFT;
452 if (offset >= roundup(plm->len, PAGE_SIZE))
453 return VM_FAULT_SIGBUS;
454
455 page = vmalloc_to_page(plm->data + offset);
456 get_page(page);
457
458 vmf->page = page;
459
460 return 0;
461 }
462
463 static const struct vm_operations_struct sel_mmap_policy_ops = {
464 .fault = sel_mmap_policy_fault,
465 .page_mkwrite = sel_mmap_policy_fault,
466 };
467
sel_mmap_policy(struct file * filp,struct vm_area_struct * vma)468 static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
469 {
470 if (vma->vm_flags & VM_SHARED) {
471 /* do not allow mprotect to make mapping writable */
472 vm_flags_clear(vma, VM_MAYWRITE);
473
474 if (vma->vm_flags & VM_WRITE)
475 return -EACCES;
476 }
477
478 vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
479 vma->vm_ops = &sel_mmap_policy_ops;
480
481 return 0;
482 }
483
484 static const struct file_operations sel_policy_ops = {
485 .open = sel_open_policy,
486 .read = sel_read_policy,
487 .mmap = sel_mmap_policy,
488 .release = sel_release_policy,
489 .llseek = generic_file_llseek,
490 };
491
sel_remove_old_bool_data(unsigned int bool_num,char ** bool_names,int * bool_values)492 static void sel_remove_old_bool_data(unsigned int bool_num, char **bool_names,
493 int *bool_values)
494 {
495 u32 i;
496
497 /* bool_dir cleanup */
498 for (i = 0; i < bool_num; i++)
499 kfree(bool_names[i]);
500 kfree(bool_names);
501 kfree(bool_values);
502 }
503
sel_make_policy_nodes(struct selinux_fs_info * fsi,struct selinux_policy * newpolicy)504 static int sel_make_policy_nodes(struct selinux_fs_info *fsi,
505 struct selinux_policy *newpolicy)
506 {
507 int ret = 0;
508 struct dentry *tmp_parent, *tmp_bool_dir, *tmp_class_dir;
509 unsigned int bool_num = 0;
510 char **bool_names = NULL;
511 int *bool_values = NULL;
512 unsigned long tmp_ino = fsi->last_ino; /* Don't increment last_ino in this function */
513
514 tmp_parent = sel_make_swapover_dir(fsi->sb, &tmp_ino);
515 if (IS_ERR(tmp_parent))
516 return PTR_ERR(tmp_parent);
517
518 tmp_ino = fsi->bool_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
519 tmp_bool_dir = sel_make_dir(tmp_parent, BOOL_DIR_NAME, &tmp_ino);
520 if (IS_ERR(tmp_bool_dir)) {
521 ret = PTR_ERR(tmp_bool_dir);
522 goto out;
523 }
524
525 tmp_ino = fsi->class_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
526 tmp_class_dir = sel_make_dir(tmp_parent, CLASS_DIR_NAME, &tmp_ino);
527 if (IS_ERR(tmp_class_dir)) {
528 ret = PTR_ERR(tmp_class_dir);
529 goto out;
530 }
531
532 ret = sel_make_bools(newpolicy, tmp_bool_dir, &bool_num,
533 &bool_names, &bool_values);
534 if (ret)
535 goto out;
536
537 ret = sel_make_classes(newpolicy, tmp_class_dir,
538 &fsi->last_class_ino);
539 if (ret)
540 goto out;
541
542 lock_rename(tmp_parent, fsi->sb->s_root);
543
544 /* booleans */
545 d_exchange(tmp_bool_dir, fsi->bool_dir);
546
547 swap(fsi->bool_num, bool_num);
548 swap(fsi->bool_pending_names, bool_names);
549 swap(fsi->bool_pending_values, bool_values);
550
551 fsi->bool_dir = tmp_bool_dir;
552
553 /* classes */
554 d_exchange(tmp_class_dir, fsi->class_dir);
555 fsi->class_dir = tmp_class_dir;
556
557 unlock_rename(tmp_parent, fsi->sb->s_root);
558
559 out:
560 sel_remove_old_bool_data(bool_num, bool_names, bool_values);
561 /* Since the other temporary dirs are children of tmp_parent
562 * this will handle all the cleanup in the case of a failure before
563 * the swapover
564 */
565 simple_recursive_removal(tmp_parent, NULL);
566
567 return ret;
568 }
569
sel_write_load(struct file * file,const char __user * buf,size_t count,loff_t * ppos)570 static ssize_t sel_write_load(struct file *file, const char __user *buf,
571 size_t count, loff_t *ppos)
572
573 {
574 struct selinux_fs_info *fsi;
575 struct selinux_load_state load_state;
576 ssize_t length;
577 void *data = NULL;
578
579 /* no partial writes */
580 if (*ppos)
581 return -EINVAL;
582 /* no empty policies */
583 if (!count)
584 return -EINVAL;
585
586 mutex_lock(&selinux_state.policy_mutex);
587
588 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
589 SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
590 if (length)
591 goto out;
592
593 data = vmalloc(count);
594 if (!data) {
595 length = -ENOMEM;
596 goto out;
597 }
598 if (copy_from_user(data, buf, count) != 0) {
599 length = -EFAULT;
600 goto out;
601 }
602
603 length = security_load_policy(data, count, &load_state);
604 if (length) {
605 pr_warn_ratelimited("SELinux: failed to load policy\n");
606 goto out;
607 }
608 fsi = file_inode(file)->i_sb->s_fs_info;
609 length = sel_make_policy_nodes(fsi, load_state.policy);
610 if (length) {
611 pr_warn_ratelimited("SELinux: failed to initialize selinuxfs\n");
612 selinux_policy_cancel(&load_state);
613 goto out;
614 }
615
616 selinux_policy_commit(&load_state);
617 length = count;
618 audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
619 "auid=%u ses=%u lsm=selinux res=1",
620 from_kuid(&init_user_ns, audit_get_loginuid(current)),
621 audit_get_sessionid(current));
622
623 out:
624 mutex_unlock(&selinux_state.policy_mutex);
625 vfree(data);
626 return length;
627 }
628
629 static const struct file_operations sel_load_ops = {
630 .write = sel_write_load,
631 .llseek = generic_file_llseek,
632 };
633
sel_write_context(struct file * file,char * buf,size_t size)634 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
635 {
636 char *canon = NULL;
637 u32 sid, len;
638 ssize_t length;
639
640 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
641 SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
642 if (length)
643 goto out;
644
645 length = security_context_to_sid(buf, size, &sid, GFP_KERNEL);
646 if (length)
647 goto out;
648
649 length = security_sid_to_context(sid, &canon, &len);
650 if (length)
651 goto out;
652
653 length = -ERANGE;
654 if (len > SIMPLE_TRANSACTION_LIMIT) {
655 pr_err("SELinux: %s: context size (%u) exceeds "
656 "payload max\n", __func__, len);
657 goto out;
658 }
659
660 memcpy(buf, canon, len);
661 length = len;
662 out:
663 kfree(canon);
664 return length;
665 }
666
sel_read_checkreqprot(struct file * filp,char __user * buf,size_t count,loff_t * ppos)667 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
668 size_t count, loff_t *ppos)
669 {
670 char tmpbuf[TMPBUFLEN];
671 ssize_t length;
672
673 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
674 checkreqprot_get());
675 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
676 }
677
sel_write_checkreqprot(struct file * file,const char __user * buf,size_t count,loff_t * ppos)678 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
679 size_t count, loff_t *ppos)
680 {
681 char *page;
682 ssize_t length;
683 unsigned int new_value;
684
685 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
686 SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
687 NULL);
688 if (length)
689 return length;
690
691 if (count >= PAGE_SIZE)
692 return -ENOMEM;
693
694 /* No partial writes. */
695 if (*ppos != 0)
696 return -EINVAL;
697
698 page = memdup_user_nul(buf, count);
699 if (IS_ERR(page))
700 return PTR_ERR(page);
701
702 if (sscanf(page, "%u", &new_value) != 1) {
703 length = -EINVAL;
704 goto out;
705 }
706 length = count;
707
708 if (new_value) {
709 char comm[sizeof(current->comm)];
710
711 memcpy(comm, current->comm, sizeof(comm));
712 pr_err("SELinux: %s (%d) set checkreqprot to 1. This is no longer supported.\n",
713 comm, current->pid);
714 }
715
716 selinux_ima_measure_state();
717
718 out:
719 kfree(page);
720 return length;
721 }
722 static const struct file_operations sel_checkreqprot_ops = {
723 .read = sel_read_checkreqprot,
724 .write = sel_write_checkreqprot,
725 .llseek = generic_file_llseek,
726 };
727
sel_write_validatetrans(struct file * file,const char __user * buf,size_t count,loff_t * ppos)728 static ssize_t sel_write_validatetrans(struct file *file,
729 const char __user *buf,
730 size_t count, loff_t *ppos)
731 {
732 char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
733 char *req = NULL;
734 u32 osid, nsid, tsid;
735 u16 tclass;
736 int rc;
737
738 rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
739 SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
740 if (rc)
741 goto out;
742
743 rc = -ENOMEM;
744 if (count >= PAGE_SIZE)
745 goto out;
746
747 /* No partial writes. */
748 rc = -EINVAL;
749 if (*ppos != 0)
750 goto out;
751
752 req = memdup_user_nul(buf, count);
753 if (IS_ERR(req)) {
754 rc = PTR_ERR(req);
755 req = NULL;
756 goto out;
757 }
758
759 rc = -ENOMEM;
760 oldcon = kzalloc(count + 1, GFP_KERNEL);
761 if (!oldcon)
762 goto out;
763
764 newcon = kzalloc(count + 1, GFP_KERNEL);
765 if (!newcon)
766 goto out;
767
768 taskcon = kzalloc(count + 1, GFP_KERNEL);
769 if (!taskcon)
770 goto out;
771
772 rc = -EINVAL;
773 if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
774 goto out;
775
776 rc = security_context_str_to_sid(oldcon, &osid, GFP_KERNEL);
777 if (rc)
778 goto out;
779
780 rc = security_context_str_to_sid(newcon, &nsid, GFP_KERNEL);
781 if (rc)
782 goto out;
783
784 rc = security_context_str_to_sid(taskcon, &tsid, GFP_KERNEL);
785 if (rc)
786 goto out;
787
788 rc = security_validate_transition_user(osid, nsid, tsid, tclass);
789 if (!rc)
790 rc = count;
791 out:
792 kfree(req);
793 kfree(oldcon);
794 kfree(newcon);
795 kfree(taskcon);
796 return rc;
797 }
798
799 static const struct file_operations sel_transition_ops = {
800 .write = sel_write_validatetrans,
801 .llseek = generic_file_llseek,
802 };
803
804 /*
805 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
806 */
807 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
808 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
809 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
810 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
811 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
812
813 static ssize_t (*const write_op[])(struct file *, char *, size_t) = {
814 [SEL_ACCESS] = sel_write_access,
815 [SEL_CREATE] = sel_write_create,
816 [SEL_RELABEL] = sel_write_relabel,
817 [SEL_USER] = sel_write_user,
818 [SEL_MEMBER] = sel_write_member,
819 [SEL_CONTEXT] = sel_write_context,
820 };
821
selinux_transaction_write(struct file * file,const char __user * buf,size_t size,loff_t * pos)822 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
823 {
824 ino_t ino = file_inode(file)->i_ino;
825 char *data;
826 ssize_t rv;
827
828 if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
829 return -EINVAL;
830
831 data = simple_transaction_get(file, buf, size);
832 if (IS_ERR(data))
833 return PTR_ERR(data);
834
835 rv = write_op[ino](file, data, size);
836 if (rv > 0) {
837 simple_transaction_set(file, rv);
838 rv = size;
839 }
840 return rv;
841 }
842
843 static const struct file_operations transaction_ops = {
844 .write = selinux_transaction_write,
845 .read = simple_transaction_read,
846 .release = simple_transaction_release,
847 .llseek = generic_file_llseek,
848 };
849
850 /*
851 * payload - write methods
852 * If the method has a response, the response should be put in buf,
853 * and the length returned. Otherwise return 0 or and -error.
854 */
855
sel_write_access(struct file * file,char * buf,size_t size)856 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
857 {
858 char *scon = NULL, *tcon = NULL;
859 u32 ssid, tsid;
860 u16 tclass;
861 struct av_decision avd;
862 ssize_t length;
863
864 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
865 SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
866 if (length)
867 goto out;
868
869 length = -ENOMEM;
870 scon = kzalloc(size + 1, GFP_KERNEL);
871 if (!scon)
872 goto out;
873
874 length = -ENOMEM;
875 tcon = kzalloc(size + 1, GFP_KERNEL);
876 if (!tcon)
877 goto out;
878
879 length = -EINVAL;
880 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
881 goto out;
882
883 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
884 if (length)
885 goto out;
886
887 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
888 if (length)
889 goto out;
890
891 security_compute_av_user(ssid, tsid, tclass, &avd);
892
893 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
894 "%x %x %x %x %u %x",
895 avd.allowed, 0xffffffff,
896 avd.auditallow, avd.auditdeny,
897 avd.seqno, avd.flags);
898 out:
899 kfree(tcon);
900 kfree(scon);
901 return length;
902 }
903
sel_write_create(struct file * file,char * buf,size_t size)904 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
905 {
906 char *scon = NULL, *tcon = NULL;
907 char *namebuf = NULL, *objname = NULL;
908 u32 ssid, tsid, newsid;
909 u16 tclass;
910 ssize_t length;
911 char *newcon = NULL;
912 u32 len;
913 int nargs;
914
915 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
916 SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
917 NULL);
918 if (length)
919 goto out;
920
921 length = -ENOMEM;
922 scon = kzalloc(size + 1, GFP_KERNEL);
923 if (!scon)
924 goto out;
925
926 length = -ENOMEM;
927 tcon = kzalloc(size + 1, GFP_KERNEL);
928 if (!tcon)
929 goto out;
930
931 length = -ENOMEM;
932 namebuf = kzalloc(size + 1, GFP_KERNEL);
933 if (!namebuf)
934 goto out;
935
936 length = -EINVAL;
937 nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
938 if (nargs < 3 || nargs > 4)
939 goto out;
940 if (nargs == 4) {
941 /*
942 * If and when the name of new object to be queried contains
943 * either whitespace or multibyte characters, they shall be
944 * encoded based on the percentage-encoding rule.
945 * If not encoded, the sscanf logic picks up only left-half
946 * of the supplied name; split by a whitespace unexpectedly.
947 */
948 char *r, *w;
949 int c1, c2;
950
951 r = w = namebuf;
952 do {
953 c1 = *r++;
954 if (c1 == '+')
955 c1 = ' ';
956 else if (c1 == '%') {
957 c1 = hex_to_bin(*r++);
958 if (c1 < 0)
959 goto out;
960 c2 = hex_to_bin(*r++);
961 if (c2 < 0)
962 goto out;
963 c1 = (c1 << 4) | c2;
964 }
965 *w++ = c1;
966 } while (c1 != '\0');
967
968 objname = namebuf;
969 }
970
971 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
972 if (length)
973 goto out;
974
975 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
976 if (length)
977 goto out;
978
979 length = security_transition_sid_user(ssid, tsid, tclass,
980 objname, &newsid);
981 if (length)
982 goto out;
983
984 length = security_sid_to_context(newsid, &newcon, &len);
985 if (length)
986 goto out;
987
988 length = -ERANGE;
989 if (len > SIMPLE_TRANSACTION_LIMIT) {
990 pr_err("SELinux: %s: context size (%u) exceeds "
991 "payload max\n", __func__, len);
992 goto out;
993 }
994
995 memcpy(buf, newcon, len);
996 length = len;
997 out:
998 kfree(newcon);
999 kfree(namebuf);
1000 kfree(tcon);
1001 kfree(scon);
1002 return length;
1003 }
1004
sel_write_relabel(struct file * file,char * buf,size_t size)1005 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
1006 {
1007 char *scon = NULL, *tcon = NULL;
1008 u32 ssid, tsid, newsid;
1009 u16 tclass;
1010 ssize_t length;
1011 char *newcon = NULL;
1012 u32 len;
1013
1014 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1015 SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
1016 NULL);
1017 if (length)
1018 goto out;
1019
1020 length = -ENOMEM;
1021 scon = kzalloc(size + 1, GFP_KERNEL);
1022 if (!scon)
1023 goto out;
1024
1025 length = -ENOMEM;
1026 tcon = kzalloc(size + 1, GFP_KERNEL);
1027 if (!tcon)
1028 goto out;
1029
1030 length = -EINVAL;
1031 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1032 goto out;
1033
1034 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
1035 if (length)
1036 goto out;
1037
1038 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
1039 if (length)
1040 goto out;
1041
1042 length = security_change_sid(ssid, tsid, tclass, &newsid);
1043 if (length)
1044 goto out;
1045
1046 length = security_sid_to_context(newsid, &newcon, &len);
1047 if (length)
1048 goto out;
1049
1050 length = -ERANGE;
1051 if (len > SIMPLE_TRANSACTION_LIMIT)
1052 goto out;
1053
1054 memcpy(buf, newcon, len);
1055 length = len;
1056 out:
1057 kfree(newcon);
1058 kfree(tcon);
1059 kfree(scon);
1060 return length;
1061 }
1062
sel_write_user(struct file * file,char * buf,size_t size)1063 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
1064 {
1065 char *con = NULL, *user = NULL, *ptr;
1066 u32 sid, *sids = NULL;
1067 ssize_t length;
1068 char *newcon;
1069 int rc;
1070 u32 i, len, nsids;
1071
1072 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1073 SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
1074 NULL);
1075 if (length)
1076 goto out;
1077
1078 length = -ENOMEM;
1079 con = kzalloc(size + 1, GFP_KERNEL);
1080 if (!con)
1081 goto out;
1082
1083 length = -ENOMEM;
1084 user = kzalloc(size + 1, GFP_KERNEL);
1085 if (!user)
1086 goto out;
1087
1088 length = -EINVAL;
1089 if (sscanf(buf, "%s %s", con, user) != 2)
1090 goto out;
1091
1092 length = security_context_str_to_sid(con, &sid, GFP_KERNEL);
1093 if (length)
1094 goto out;
1095
1096 length = security_get_user_sids(sid, user, &sids, &nsids);
1097 if (length)
1098 goto out;
1099
1100 length = sprintf(buf, "%u", nsids) + 1;
1101 ptr = buf + length;
1102 for (i = 0; i < nsids; i++) {
1103 rc = security_sid_to_context(sids[i], &newcon, &len);
1104 if (rc) {
1105 length = rc;
1106 goto out;
1107 }
1108 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1109 kfree(newcon);
1110 length = -ERANGE;
1111 goto out;
1112 }
1113 memcpy(ptr, newcon, len);
1114 kfree(newcon);
1115 ptr += len;
1116 length += len;
1117 }
1118 out:
1119 kfree(sids);
1120 kfree(user);
1121 kfree(con);
1122 return length;
1123 }
1124
sel_write_member(struct file * file,char * buf,size_t size)1125 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1126 {
1127 char *scon = NULL, *tcon = NULL;
1128 u32 ssid, tsid, newsid;
1129 u16 tclass;
1130 ssize_t length;
1131 char *newcon = NULL;
1132 u32 len;
1133
1134 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1135 SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
1136 NULL);
1137 if (length)
1138 goto out;
1139
1140 length = -ENOMEM;
1141 scon = kzalloc(size + 1, GFP_KERNEL);
1142 if (!scon)
1143 goto out;
1144
1145 length = -ENOMEM;
1146 tcon = kzalloc(size + 1, GFP_KERNEL);
1147 if (!tcon)
1148 goto out;
1149
1150 length = -EINVAL;
1151 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1152 goto out;
1153
1154 length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
1155 if (length)
1156 goto out;
1157
1158 length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
1159 if (length)
1160 goto out;
1161
1162 length = security_member_sid(ssid, tsid, tclass, &newsid);
1163 if (length)
1164 goto out;
1165
1166 length = security_sid_to_context(newsid, &newcon, &len);
1167 if (length)
1168 goto out;
1169
1170 length = -ERANGE;
1171 if (len > SIMPLE_TRANSACTION_LIMIT) {
1172 pr_err("SELinux: %s: context size (%u) exceeds "
1173 "payload max\n", __func__, len);
1174 goto out;
1175 }
1176
1177 memcpy(buf, newcon, len);
1178 length = len;
1179 out:
1180 kfree(newcon);
1181 kfree(tcon);
1182 kfree(scon);
1183 return length;
1184 }
1185
sel_make_inode(struct super_block * sb,umode_t mode)1186 static struct inode *sel_make_inode(struct super_block *sb, umode_t mode)
1187 {
1188 struct inode *ret = new_inode(sb);
1189
1190 if (ret) {
1191 ret->i_mode = mode;
1192 simple_inode_init_ts(ret);
1193 }
1194 return ret;
1195 }
1196
sel_read_bool(struct file * filep,char __user * buf,size_t count,loff_t * ppos)1197 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1198 size_t count, loff_t *ppos)
1199 {
1200 struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1201 char *page = NULL;
1202 ssize_t length;
1203 ssize_t ret;
1204 int cur_enforcing;
1205 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1206 const char *name = filep->f_path.dentry->d_name.name;
1207
1208 mutex_lock(&selinux_state.policy_mutex);
1209
1210 ret = -EINVAL;
1211 if (index >= fsi->bool_num || strcmp(name,
1212 fsi->bool_pending_names[index]))
1213 goto out_unlock;
1214
1215 ret = -ENOMEM;
1216 page = (char *)get_zeroed_page(GFP_KERNEL);
1217 if (!page)
1218 goto out_unlock;
1219
1220 cur_enforcing = security_get_bool_value(index);
1221 if (cur_enforcing < 0) {
1222 ret = cur_enforcing;
1223 goto out_unlock;
1224 }
1225 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1226 fsi->bool_pending_values[index]);
1227 mutex_unlock(&selinux_state.policy_mutex);
1228 ret = simple_read_from_buffer(buf, count, ppos, page, length);
1229 out_free:
1230 free_page((unsigned long)page);
1231 return ret;
1232
1233 out_unlock:
1234 mutex_unlock(&selinux_state.policy_mutex);
1235 goto out_free;
1236 }
1237
sel_write_bool(struct file * filep,const char __user * buf,size_t count,loff_t * ppos)1238 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1239 size_t count, loff_t *ppos)
1240 {
1241 struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1242 char *page = NULL;
1243 ssize_t length;
1244 int new_value;
1245 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1246 const char *name = filep->f_path.dentry->d_name.name;
1247
1248 if (count >= PAGE_SIZE)
1249 return -ENOMEM;
1250
1251 /* No partial writes. */
1252 if (*ppos != 0)
1253 return -EINVAL;
1254
1255 page = memdup_user_nul(buf, count);
1256 if (IS_ERR(page))
1257 return PTR_ERR(page);
1258
1259 mutex_lock(&selinux_state.policy_mutex);
1260
1261 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1262 SECCLASS_SECURITY, SECURITY__SETBOOL,
1263 NULL);
1264 if (length)
1265 goto out;
1266
1267 length = -EINVAL;
1268 if (index >= fsi->bool_num || strcmp(name,
1269 fsi->bool_pending_names[index]))
1270 goto out;
1271
1272 length = -EINVAL;
1273 if (sscanf(page, "%d", &new_value) != 1)
1274 goto out;
1275
1276 if (new_value)
1277 new_value = 1;
1278
1279 fsi->bool_pending_values[index] = new_value;
1280 length = count;
1281
1282 out:
1283 mutex_unlock(&selinux_state.policy_mutex);
1284 kfree(page);
1285 return length;
1286 }
1287
1288 static const struct file_operations sel_bool_ops = {
1289 .read = sel_read_bool,
1290 .write = sel_write_bool,
1291 .llseek = generic_file_llseek,
1292 };
1293
sel_commit_bools_write(struct file * filep,const char __user * buf,size_t count,loff_t * ppos)1294 static ssize_t sel_commit_bools_write(struct file *filep,
1295 const char __user *buf,
1296 size_t count, loff_t *ppos)
1297 {
1298 struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1299 char *page = NULL;
1300 ssize_t length;
1301 int new_value;
1302
1303 if (count >= PAGE_SIZE)
1304 return -ENOMEM;
1305
1306 /* No partial writes. */
1307 if (*ppos != 0)
1308 return -EINVAL;
1309
1310 page = memdup_user_nul(buf, count);
1311 if (IS_ERR(page))
1312 return PTR_ERR(page);
1313
1314 mutex_lock(&selinux_state.policy_mutex);
1315
1316 length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1317 SECCLASS_SECURITY, SECURITY__SETBOOL,
1318 NULL);
1319 if (length)
1320 goto out;
1321
1322 length = -EINVAL;
1323 if (sscanf(page, "%d", &new_value) != 1)
1324 goto out;
1325
1326 length = 0;
1327 if (new_value && fsi->bool_pending_values)
1328 length = security_set_bools(fsi->bool_num,
1329 fsi->bool_pending_values);
1330
1331 if (!length)
1332 length = count;
1333
1334 out:
1335 mutex_unlock(&selinux_state.policy_mutex);
1336 kfree(page);
1337 return length;
1338 }
1339
1340 static const struct file_operations sel_commit_bools_ops = {
1341 .write = sel_commit_bools_write,
1342 .llseek = generic_file_llseek,
1343 };
1344
sel_make_bools(struct selinux_policy * newpolicy,struct dentry * bool_dir,unsigned int * bool_num,char *** bool_pending_names,int ** bool_pending_values)1345 static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
1346 unsigned int *bool_num, char ***bool_pending_names,
1347 int **bool_pending_values)
1348 {
1349 int ret;
1350 char **names, *page;
1351 u32 i, num;
1352
1353 page = (char *)get_zeroed_page(GFP_KERNEL);
1354 if (!page)
1355 return -ENOMEM;
1356
1357 ret = security_get_bools(newpolicy, &num, &names, bool_pending_values);
1358 if (ret)
1359 goto out;
1360
1361 *bool_num = num;
1362 *bool_pending_names = names;
1363
1364 for (i = 0; i < num; i++) {
1365 struct dentry *dentry;
1366 struct inode *inode;
1367 struct inode_security_struct *isec;
1368 ssize_t len;
1369 u32 sid;
1370
1371 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1372 if (len >= PAGE_SIZE) {
1373 ret = -ENAMETOOLONG;
1374 break;
1375 }
1376 dentry = d_alloc_name(bool_dir, names[i]);
1377 if (!dentry) {
1378 ret = -ENOMEM;
1379 break;
1380 }
1381
1382 inode = sel_make_inode(bool_dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1383 if (!inode) {
1384 dput(dentry);
1385 ret = -ENOMEM;
1386 break;
1387 }
1388
1389 isec = selinux_inode(inode);
1390 ret = selinux_policy_genfs_sid(newpolicy, "selinuxfs", page,
1391 SECCLASS_FILE, &sid);
1392 if (ret) {
1393 pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
1394 page);
1395 sid = SECINITSID_SECURITY;
1396 }
1397
1398 isec->sid = sid;
1399 isec->initialized = LABEL_INITIALIZED;
1400 inode->i_fop = &sel_bool_ops;
1401 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1402 d_add(dentry, inode);
1403 }
1404 out:
1405 free_page((unsigned long)page);
1406 return ret;
1407 }
1408
sel_read_avc_cache_threshold(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1409 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1410 size_t count, loff_t *ppos)
1411 {
1412 char tmpbuf[TMPBUFLEN];
1413 ssize_t length;
1414
1415 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1416 avc_get_cache_threshold());
1417 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1418 }
1419
sel_write_avc_cache_threshold(struct file * file,const char __user * buf,size_t count,loff_t * ppos)1420 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1421 const char __user *buf,
1422 size_t count, loff_t *ppos)
1423
1424 {
1425 char *page;
1426 ssize_t ret;
1427 unsigned int new_value;
1428
1429 ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1430 SECCLASS_SECURITY, SECURITY__SETSECPARAM,
1431 NULL);
1432 if (ret)
1433 return ret;
1434
1435 if (count >= PAGE_SIZE)
1436 return -ENOMEM;
1437
1438 /* No partial writes. */
1439 if (*ppos != 0)
1440 return -EINVAL;
1441
1442 page = memdup_user_nul(buf, count);
1443 if (IS_ERR(page))
1444 return PTR_ERR(page);
1445
1446 ret = -EINVAL;
1447 if (sscanf(page, "%u", &new_value) != 1)
1448 goto out;
1449
1450 avc_set_cache_threshold(new_value);
1451
1452 ret = count;
1453 out:
1454 kfree(page);
1455 return ret;
1456 }
1457
sel_read_avc_hash_stats(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1458 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1459 size_t count, loff_t *ppos)
1460 {
1461 char *page;
1462 ssize_t length;
1463
1464 page = (char *)__get_free_page(GFP_KERNEL);
1465 if (!page)
1466 return -ENOMEM;
1467
1468 length = avc_get_hash_stats(page);
1469 if (length >= 0)
1470 length = simple_read_from_buffer(buf, count, ppos, page, length);
1471 free_page((unsigned long)page);
1472
1473 return length;
1474 }
1475
sel_read_sidtab_hash_stats(struct file * filp,char __user * buf,size_t count,loff_t * ppos)1476 static ssize_t sel_read_sidtab_hash_stats(struct file *filp, char __user *buf,
1477 size_t count, loff_t *ppos)
1478 {
1479 char *page;
1480 ssize_t length;
1481
1482 page = (char *)__get_free_page(GFP_KERNEL);
1483 if (!page)
1484 return -ENOMEM;
1485
1486 length = security_sidtab_hash_stats(page);
1487 if (length >= 0)
1488 length = simple_read_from_buffer(buf, count, ppos, page,
1489 length);
1490 free_page((unsigned long)page);
1491
1492 return length;
1493 }
1494
1495 static const struct file_operations sel_sidtab_hash_stats_ops = {
1496 .read = sel_read_sidtab_hash_stats,
1497 .llseek = generic_file_llseek,
1498 };
1499
1500 static const struct file_operations sel_avc_cache_threshold_ops = {
1501 .read = sel_read_avc_cache_threshold,
1502 .write = sel_write_avc_cache_threshold,
1503 .llseek = generic_file_llseek,
1504 };
1505
1506 static const struct file_operations sel_avc_hash_stats_ops = {
1507 .read = sel_read_avc_hash_stats,
1508 .llseek = generic_file_llseek,
1509 };
1510
1511 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
sel_avc_get_stat_idx(loff_t * idx)1512 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1513 {
1514 int cpu;
1515
1516 for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1517 if (!cpu_possible(cpu))
1518 continue;
1519 *idx = cpu + 1;
1520 return &per_cpu(avc_cache_stats, cpu);
1521 }
1522 (*idx)++;
1523 return NULL;
1524 }
1525
sel_avc_stats_seq_start(struct seq_file * seq,loff_t * pos)1526 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1527 {
1528 loff_t n = *pos - 1;
1529
1530 if (*pos == 0)
1531 return SEQ_START_TOKEN;
1532
1533 return sel_avc_get_stat_idx(&n);
1534 }
1535
sel_avc_stats_seq_next(struct seq_file * seq,void * v,loff_t * pos)1536 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1537 {
1538 return sel_avc_get_stat_idx(pos);
1539 }
1540
sel_avc_stats_seq_show(struct seq_file * seq,void * v)1541 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1542 {
1543 struct avc_cache_stats *st = v;
1544
1545 if (v == SEQ_START_TOKEN) {
1546 seq_puts(seq,
1547 "lookups hits misses allocations reclaims frees\n");
1548 } else {
1549 unsigned int lookups = st->lookups;
1550 unsigned int misses = st->misses;
1551 unsigned int hits = lookups - misses;
1552 seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1553 hits, misses, st->allocations,
1554 st->reclaims, st->frees);
1555 }
1556 return 0;
1557 }
1558
sel_avc_stats_seq_stop(struct seq_file * seq,void * v)1559 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1560 { }
1561
1562 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1563 .start = sel_avc_stats_seq_start,
1564 .next = sel_avc_stats_seq_next,
1565 .show = sel_avc_stats_seq_show,
1566 .stop = sel_avc_stats_seq_stop,
1567 };
1568
sel_open_avc_cache_stats(struct inode * inode,struct file * file)1569 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1570 {
1571 return seq_open(file, &sel_avc_cache_stats_seq_ops);
1572 }
1573
1574 static const struct file_operations sel_avc_cache_stats_ops = {
1575 .open = sel_open_avc_cache_stats,
1576 .read = seq_read,
1577 .llseek = seq_lseek,
1578 .release = seq_release,
1579 };
1580 #endif
1581
sel_make_avc_files(struct dentry * dir)1582 static int sel_make_avc_files(struct dentry *dir)
1583 {
1584 struct super_block *sb = dir->d_sb;
1585 struct selinux_fs_info *fsi = sb->s_fs_info;
1586 unsigned int i;
1587 static const struct tree_descr files[] = {
1588 { "cache_threshold",
1589 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1590 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1591 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1592 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1593 #endif
1594 };
1595
1596 for (i = 0; i < ARRAY_SIZE(files); i++) {
1597 struct inode *inode;
1598 struct dentry *dentry;
1599
1600 dentry = d_alloc_name(dir, files[i].name);
1601 if (!dentry)
1602 return -ENOMEM;
1603
1604 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1605 if (!inode) {
1606 dput(dentry);
1607 return -ENOMEM;
1608 }
1609
1610 inode->i_fop = files[i].ops;
1611 inode->i_ino = ++fsi->last_ino;
1612 d_add(dentry, inode);
1613 }
1614
1615 return 0;
1616 }
1617
sel_make_ss_files(struct dentry * dir)1618 static int sel_make_ss_files(struct dentry *dir)
1619 {
1620 struct super_block *sb = dir->d_sb;
1621 struct selinux_fs_info *fsi = sb->s_fs_info;
1622 unsigned int i;
1623 static const struct tree_descr files[] = {
1624 { "sidtab_hash_stats", &sel_sidtab_hash_stats_ops, S_IRUGO },
1625 };
1626
1627 for (i = 0; i < ARRAY_SIZE(files); i++) {
1628 struct inode *inode;
1629 struct dentry *dentry;
1630
1631 dentry = d_alloc_name(dir, files[i].name);
1632 if (!dentry)
1633 return -ENOMEM;
1634
1635 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1636 if (!inode) {
1637 dput(dentry);
1638 return -ENOMEM;
1639 }
1640
1641 inode->i_fop = files[i].ops;
1642 inode->i_ino = ++fsi->last_ino;
1643 d_add(dentry, inode);
1644 }
1645
1646 return 0;
1647 }
1648
sel_read_initcon(struct file * file,char __user * buf,size_t count,loff_t * ppos)1649 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1650 size_t count, loff_t *ppos)
1651 {
1652 char *con;
1653 u32 sid, len;
1654 ssize_t ret;
1655
1656 sid = file_inode(file)->i_ino&SEL_INO_MASK;
1657 ret = security_sid_to_context(sid, &con, &len);
1658 if (ret)
1659 return ret;
1660
1661 ret = simple_read_from_buffer(buf, count, ppos, con, len);
1662 kfree(con);
1663 return ret;
1664 }
1665
1666 static const struct file_operations sel_initcon_ops = {
1667 .read = sel_read_initcon,
1668 .llseek = generic_file_llseek,
1669 };
1670
sel_make_initcon_files(struct dentry * dir)1671 static int sel_make_initcon_files(struct dentry *dir)
1672 {
1673 unsigned int i;
1674
1675 for (i = 1; i <= SECINITSID_NUM; i++) {
1676 struct inode *inode;
1677 struct dentry *dentry;
1678 const char *s = security_get_initial_sid_context(i);
1679
1680 if (!s)
1681 continue;
1682 dentry = d_alloc_name(dir, s);
1683 if (!dentry)
1684 return -ENOMEM;
1685
1686 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1687 if (!inode) {
1688 dput(dentry);
1689 return -ENOMEM;
1690 }
1691
1692 inode->i_fop = &sel_initcon_ops;
1693 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1694 d_add(dentry, inode);
1695 }
1696
1697 return 0;
1698 }
1699
sel_class_to_ino(u16 class)1700 static inline unsigned long sel_class_to_ino(u16 class)
1701 {
1702 return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1703 }
1704
sel_ino_to_class(unsigned long ino)1705 static inline u16 sel_ino_to_class(unsigned long ino)
1706 {
1707 return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1708 }
1709
sel_perm_to_ino(u16 class,u32 perm)1710 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1711 {
1712 return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1713 }
1714
sel_ino_to_perm(unsigned long ino)1715 static inline u32 sel_ino_to_perm(unsigned long ino)
1716 {
1717 return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1718 }
1719
sel_read_class(struct file * file,char __user * buf,size_t count,loff_t * ppos)1720 static ssize_t sel_read_class(struct file *file, char __user *buf,
1721 size_t count, loff_t *ppos)
1722 {
1723 unsigned long ino = file_inode(file)->i_ino;
1724 char res[TMPBUFLEN];
1725 ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1726 return simple_read_from_buffer(buf, count, ppos, res, len);
1727 }
1728
1729 static const struct file_operations sel_class_ops = {
1730 .read = sel_read_class,
1731 .llseek = generic_file_llseek,
1732 };
1733
sel_read_perm(struct file * file,char __user * buf,size_t count,loff_t * ppos)1734 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1735 size_t count, loff_t *ppos)
1736 {
1737 unsigned long ino = file_inode(file)->i_ino;
1738 char res[TMPBUFLEN];
1739 ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1740 return simple_read_from_buffer(buf, count, ppos, res, len);
1741 }
1742
1743 static const struct file_operations sel_perm_ops = {
1744 .read = sel_read_perm,
1745 .llseek = generic_file_llseek,
1746 };
1747
sel_read_policycap(struct file * file,char __user * buf,size_t count,loff_t * ppos)1748 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1749 size_t count, loff_t *ppos)
1750 {
1751 int value;
1752 char tmpbuf[TMPBUFLEN];
1753 ssize_t length;
1754 unsigned long i_ino = file_inode(file)->i_ino;
1755
1756 value = security_policycap_supported(i_ino & SEL_INO_MASK);
1757 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1758
1759 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1760 }
1761
1762 static const struct file_operations sel_policycap_ops = {
1763 .read = sel_read_policycap,
1764 .llseek = generic_file_llseek,
1765 };
1766
sel_make_perm_files(struct selinux_policy * newpolicy,char * objclass,int classvalue,struct dentry * dir)1767 static int sel_make_perm_files(struct selinux_policy *newpolicy,
1768 char *objclass, int classvalue,
1769 struct dentry *dir)
1770 {
1771 u32 i, nperms;
1772 int rc;
1773 char **perms;
1774
1775 rc = security_get_permissions(newpolicy, objclass, &perms, &nperms);
1776 if (rc)
1777 return rc;
1778
1779 for (i = 0; i < nperms; i++) {
1780 struct inode *inode;
1781 struct dentry *dentry;
1782
1783 rc = -ENOMEM;
1784 dentry = d_alloc_name(dir, perms[i]);
1785 if (!dentry)
1786 goto out;
1787
1788 rc = -ENOMEM;
1789 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1790 if (!inode) {
1791 dput(dentry);
1792 goto out;
1793 }
1794
1795 inode->i_fop = &sel_perm_ops;
1796 /* i+1 since perm values are 1-indexed */
1797 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1798 d_add(dentry, inode);
1799 }
1800 rc = 0;
1801 out:
1802 for (i = 0; i < nperms; i++)
1803 kfree(perms[i]);
1804 kfree(perms);
1805 return rc;
1806 }
1807
sel_make_class_dir_entries(struct selinux_policy * newpolicy,char * classname,int index,struct dentry * dir)1808 static int sel_make_class_dir_entries(struct selinux_policy *newpolicy,
1809 char *classname, int index,
1810 struct dentry *dir)
1811 {
1812 struct super_block *sb = dir->d_sb;
1813 struct selinux_fs_info *fsi = sb->s_fs_info;
1814 struct dentry *dentry = NULL;
1815 struct inode *inode = NULL;
1816
1817 dentry = d_alloc_name(dir, "index");
1818 if (!dentry)
1819 return -ENOMEM;
1820
1821 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1822 if (!inode) {
1823 dput(dentry);
1824 return -ENOMEM;
1825 }
1826
1827 inode->i_fop = &sel_class_ops;
1828 inode->i_ino = sel_class_to_ino(index);
1829 d_add(dentry, inode);
1830
1831 dentry = sel_make_dir(dir, "perms", &fsi->last_class_ino);
1832 if (IS_ERR(dentry))
1833 return PTR_ERR(dentry);
1834
1835 return sel_make_perm_files(newpolicy, classname, index, dentry);
1836 }
1837
sel_make_classes(struct selinux_policy * newpolicy,struct dentry * class_dir,unsigned long * last_class_ino)1838 static int sel_make_classes(struct selinux_policy *newpolicy,
1839 struct dentry *class_dir,
1840 unsigned long *last_class_ino)
1841 {
1842 u32 i, nclasses;
1843 int rc;
1844 char **classes;
1845
1846 rc = security_get_classes(newpolicy, &classes, &nclasses);
1847 if (rc)
1848 return rc;
1849
1850 /* +2 since classes are 1-indexed */
1851 *last_class_ino = sel_class_to_ino(nclasses + 2);
1852
1853 for (i = 0; i < nclasses; i++) {
1854 struct dentry *class_name_dir;
1855
1856 class_name_dir = sel_make_dir(class_dir, classes[i],
1857 last_class_ino);
1858 if (IS_ERR(class_name_dir)) {
1859 rc = PTR_ERR(class_name_dir);
1860 goto out;
1861 }
1862
1863 /* i+1 since class values are 1-indexed */
1864 rc = sel_make_class_dir_entries(newpolicy, classes[i], i + 1,
1865 class_name_dir);
1866 if (rc)
1867 goto out;
1868 }
1869 rc = 0;
1870 out:
1871 for (i = 0; i < nclasses; i++)
1872 kfree(classes[i]);
1873 kfree(classes);
1874 return rc;
1875 }
1876
sel_make_policycap(struct selinux_fs_info * fsi)1877 static int sel_make_policycap(struct selinux_fs_info *fsi)
1878 {
1879 unsigned int iter;
1880 struct dentry *dentry = NULL;
1881 struct inode *inode = NULL;
1882
1883 for (iter = 0; iter <= POLICYDB_CAP_MAX; iter++) {
1884 if (iter < ARRAY_SIZE(selinux_policycap_names))
1885 dentry = d_alloc_name(fsi->policycap_dir,
1886 selinux_policycap_names[iter]);
1887 else
1888 dentry = d_alloc_name(fsi->policycap_dir, "unknown");
1889
1890 if (dentry == NULL)
1891 return -ENOMEM;
1892
1893 inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
1894 if (inode == NULL) {
1895 dput(dentry);
1896 return -ENOMEM;
1897 }
1898
1899 inode->i_fop = &sel_policycap_ops;
1900 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1901 d_add(dentry, inode);
1902 }
1903
1904 return 0;
1905 }
1906
sel_make_dir(struct dentry * dir,const char * name,unsigned long * ino)1907 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1908 unsigned long *ino)
1909 {
1910 struct dentry *dentry = d_alloc_name(dir, name);
1911 struct inode *inode;
1912
1913 if (!dentry)
1914 return ERR_PTR(-ENOMEM);
1915
1916 inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1917 if (!inode) {
1918 dput(dentry);
1919 return ERR_PTR(-ENOMEM);
1920 }
1921
1922 inode->i_op = &simple_dir_inode_operations;
1923 inode->i_fop = &simple_dir_operations;
1924 inode->i_ino = ++(*ino);
1925 /* directory inodes start off with i_nlink == 2 (for "." entry) */
1926 inc_nlink(inode);
1927 d_add(dentry, inode);
1928 /* bump link count on parent directory, too */
1929 inc_nlink(d_inode(dir));
1930
1931 return dentry;
1932 }
1933
reject_all(struct mnt_idmap * idmap,struct inode * inode,int mask)1934 static int reject_all(struct mnt_idmap *idmap, struct inode *inode, int mask)
1935 {
1936 return -EPERM; // no access for anyone, root or no root.
1937 }
1938
1939 static const struct inode_operations swapover_dir_inode_operations = {
1940 .lookup = simple_lookup,
1941 .permission = reject_all,
1942 };
1943
sel_make_swapover_dir(struct super_block * sb,unsigned long * ino)1944 static struct dentry *sel_make_swapover_dir(struct super_block *sb,
1945 unsigned long *ino)
1946 {
1947 struct dentry *dentry = d_alloc_name(sb->s_root, ".swapover");
1948 struct inode *inode;
1949
1950 if (!dentry)
1951 return ERR_PTR(-ENOMEM);
1952
1953 inode = sel_make_inode(sb, S_IFDIR);
1954 if (!inode) {
1955 dput(dentry);
1956 return ERR_PTR(-ENOMEM);
1957 }
1958
1959 inode->i_op = &swapover_dir_inode_operations;
1960 inode->i_ino = ++(*ino);
1961 /* directory inodes start off with i_nlink == 2 (for "." entry) */
1962 inc_nlink(inode);
1963 inode_lock(sb->s_root->d_inode);
1964 d_add(dentry, inode);
1965 inc_nlink(sb->s_root->d_inode);
1966 inode_unlock(sb->s_root->d_inode);
1967 return dentry;
1968 }
1969
1970 #define NULL_FILE_NAME "null"
1971
sel_fill_super(struct super_block * sb,struct fs_context * fc)1972 static int sel_fill_super(struct super_block *sb, struct fs_context *fc)
1973 {
1974 struct selinux_fs_info *fsi;
1975 int ret;
1976 struct dentry *dentry;
1977 struct inode *inode;
1978 struct inode_security_struct *isec;
1979
1980 static const struct tree_descr selinux_files[] = {
1981 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1982 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1983 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1984 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1985 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1986 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1987 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1988 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1989 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1990 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1991 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1992 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1993 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1994 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1995 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1996 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1997 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
1998 [SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
1999 S_IWUGO},
2000 /* last one */ {""}
2001 };
2002
2003 ret = selinux_fs_info_create(sb);
2004 if (ret)
2005 goto err;
2006
2007 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
2008 if (ret)
2009 goto err;
2010
2011 fsi = sb->s_fs_info;
2012 fsi->bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &fsi->last_ino);
2013 if (IS_ERR(fsi->bool_dir)) {
2014 ret = PTR_ERR(fsi->bool_dir);
2015 fsi->bool_dir = NULL;
2016 goto err;
2017 }
2018
2019 ret = -ENOMEM;
2020 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
2021 if (!dentry)
2022 goto err;
2023
2024 ret = -ENOMEM;
2025 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
2026 if (!inode) {
2027 dput(dentry);
2028 goto err;
2029 }
2030
2031 inode->i_ino = ++fsi->last_ino;
2032 isec = selinux_inode(inode);
2033 isec->sid = SECINITSID_DEVNULL;
2034 isec->sclass = SECCLASS_CHR_FILE;
2035 isec->initialized = LABEL_INITIALIZED;
2036
2037 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
2038 d_add(dentry, inode);
2039
2040 dentry = sel_make_dir(sb->s_root, "avc", &fsi->last_ino);
2041 if (IS_ERR(dentry)) {
2042 ret = PTR_ERR(dentry);
2043 goto err;
2044 }
2045
2046 ret = sel_make_avc_files(dentry);
2047 if (ret)
2048 goto err;
2049
2050 dentry = sel_make_dir(sb->s_root, "ss", &fsi->last_ino);
2051 if (IS_ERR(dentry)) {
2052 ret = PTR_ERR(dentry);
2053 goto err;
2054 }
2055
2056 ret = sel_make_ss_files(dentry);
2057 if (ret)
2058 goto err;
2059
2060 dentry = sel_make_dir(sb->s_root, "initial_contexts", &fsi->last_ino);
2061 if (IS_ERR(dentry)) {
2062 ret = PTR_ERR(dentry);
2063 goto err;
2064 }
2065
2066 ret = sel_make_initcon_files(dentry);
2067 if (ret)
2068 goto err;
2069
2070 fsi->class_dir = sel_make_dir(sb->s_root, CLASS_DIR_NAME, &fsi->last_ino);
2071 if (IS_ERR(fsi->class_dir)) {
2072 ret = PTR_ERR(fsi->class_dir);
2073 fsi->class_dir = NULL;
2074 goto err;
2075 }
2076
2077 fsi->policycap_dir = sel_make_dir(sb->s_root, POLICYCAP_DIR_NAME,
2078 &fsi->last_ino);
2079 if (IS_ERR(fsi->policycap_dir)) {
2080 ret = PTR_ERR(fsi->policycap_dir);
2081 fsi->policycap_dir = NULL;
2082 goto err;
2083 }
2084
2085 ret = sel_make_policycap(fsi);
2086 if (ret) {
2087 pr_err("SELinux: failed to load policy capabilities\n");
2088 goto err;
2089 }
2090
2091 return 0;
2092 err:
2093 pr_err("SELinux: %s: failed while creating inodes\n",
2094 __func__);
2095
2096 selinux_fs_info_free(sb);
2097
2098 return ret;
2099 }
2100
sel_get_tree(struct fs_context * fc)2101 static int sel_get_tree(struct fs_context *fc)
2102 {
2103 return get_tree_single(fc, sel_fill_super);
2104 }
2105
2106 static const struct fs_context_operations sel_context_ops = {
2107 .get_tree = sel_get_tree,
2108 };
2109
sel_init_fs_context(struct fs_context * fc)2110 static int sel_init_fs_context(struct fs_context *fc)
2111 {
2112 fc->ops = &sel_context_ops;
2113 return 0;
2114 }
2115
sel_kill_sb(struct super_block * sb)2116 static void sel_kill_sb(struct super_block *sb)
2117 {
2118 selinux_fs_info_free(sb);
2119 kill_litter_super(sb);
2120 }
2121
2122 static struct file_system_type sel_fs_type = {
2123 .name = "selinuxfs",
2124 .init_fs_context = sel_init_fs_context,
2125 .kill_sb = sel_kill_sb,
2126 };
2127
2128 struct path selinux_null __ro_after_init;
2129
init_sel_fs(void)2130 static int __init init_sel_fs(void)
2131 {
2132 struct qstr null_name = QSTR_INIT(NULL_FILE_NAME,
2133 sizeof(NULL_FILE_NAME)-1);
2134 int err;
2135
2136 if (!selinux_enabled_boot)
2137 return 0;
2138
2139 err = sysfs_create_mount_point(fs_kobj, "selinux");
2140 if (err)
2141 return err;
2142
2143 err = register_filesystem(&sel_fs_type);
2144 if (err) {
2145 sysfs_remove_mount_point(fs_kobj, "selinux");
2146 return err;
2147 }
2148
2149 selinux_null.mnt = kern_mount(&sel_fs_type);
2150 if (IS_ERR(selinux_null.mnt)) {
2151 pr_err("selinuxfs: could not mount!\n");
2152 err = PTR_ERR(selinux_null.mnt);
2153 selinux_null.mnt = NULL;
2154 return err;
2155 }
2156
2157 selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root,
2158 &null_name);
2159 if (IS_ERR(selinux_null.dentry)) {
2160 pr_err("selinuxfs: could not lookup null!\n");
2161 err = PTR_ERR(selinux_null.dentry);
2162 selinux_null.dentry = NULL;
2163 return err;
2164 }
2165
2166 /*
2167 * Try to pre-allocate the status page, so the sequence number of the
2168 * initial policy load can be stored.
2169 */
2170 (void) selinux_kernel_status_page();
2171
2172 return err;
2173 }
2174
2175 __initcall(init_sel_fs);
2176