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1/*
2 * AppArmor security module
3 *
4 * This file contains AppArmor LSM hooks.
5 *
6 * Copyright (C) 1998-2008 Novell/SUSE
7 * Copyright 2009-2010 Canonical Ltd.
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation, version 2 of the
12 * License.
13 */
14
15#include <linux/security.h>
16#include <linux/moduleparam.h>
17#include <linux/mm.h>
18#include <linux/mman.h>
19#include <linux/mount.h>
20#include <linux/namei.h>
21#include <linux/ptrace.h>
22#include <linux/ctype.h>
23#include <linux/sysctl.h>
24#include <linux/audit.h>
25#include <linux/user_namespace.h>
26#include <net/sock.h>
27
28#include "include/apparmor.h"
29#include "include/apparmorfs.h"
30#include "include/audit.h"
31#include "include/capability.h"
32#include "include/context.h"
33#include "include/file.h"
34#include "include/ipc.h"
35#include "include/path.h"
36#include "include/policy.h"
37#include "include/procattr.h"
38
39/* Flag indicating whether initialization completed */
40int apparmor_initialized __initdata;
41
42/*
43 * LSM hook functions
44 */
45
46/*
47 * free the associated aa_task_cxt and put its profiles
48 */
49static void apparmor_cred_free(struct cred *cred)
50{
51 aa_free_task_context(cred_cxt(cred));
52 cred_cxt(cred) = NULL;
53}
54
55/*
56 * allocate the apparmor part of blank credentials
57 */
58static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
59{
60 /* freed by apparmor_cred_free */
61 struct aa_task_cxt *cxt = aa_alloc_task_context(gfp);
62 if (!cxt)
63 return -ENOMEM;
64
65 cred_cxt(cred) = cxt;
66 return 0;
67}
68
69/*
70 * prepare new aa_task_cxt for modification by prepare_cred block
71 */
72static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
73 gfp_t gfp)
74{
75 /* freed by apparmor_cred_free */
76 struct aa_task_cxt *cxt = aa_alloc_task_context(gfp);
77 if (!cxt)
78 return -ENOMEM;
79
80 aa_dup_task_context(cxt, cred_cxt(old));
81 cred_cxt(new) = cxt;
82 return 0;
83}
84
85/*
86 * transfer the apparmor data to a blank set of creds
87 */
88static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
89{
90 const struct aa_task_cxt *old_cxt = cred_cxt(old);
91 struct aa_task_cxt *new_cxt = cred_cxt(new);
92
93 aa_dup_task_context(new_cxt, old_cxt);
94}
95
96static int apparmor_ptrace_access_check(struct task_struct *child,
97 unsigned int mode)
98{
99 int error = cap_ptrace_access_check(child, mode);
100 if (error)
101 return error;
102
103 return aa_ptrace(current, child, mode);
104}
105
106static int apparmor_ptrace_traceme(struct task_struct *parent)
107{
108 int error = cap_ptrace_traceme(parent);
109 if (error)
110 return error;
111
112 return aa_ptrace(parent, current, PTRACE_MODE_ATTACH);
113}
114
115/* Derived from security/commoncap.c:cap_capget */
116static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
117 kernel_cap_t *inheritable, kernel_cap_t *permitted)
118{
119 struct aa_profile *profile;
120 const struct cred *cred;
121
122 rcu_read_lock();
123 cred = __task_cred(target);
124 profile = aa_cred_profile(cred);
125
126 *effective = cred->cap_effective;
127 *inheritable = cred->cap_inheritable;
128 *permitted = cred->cap_permitted;
129
130 if (!unconfined(profile) && !COMPLAIN_MODE(profile)) {
131 *effective = cap_intersect(*effective, profile->caps.allow);
132 *permitted = cap_intersect(*permitted, profile->caps.allow);
133 }
134 rcu_read_unlock();
135
136 return 0;
137}
138
139static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
140 int cap, int audit)
141{
142 struct aa_profile *profile;
143 /* cap_capable returns 0 on success, else -EPERM */
144 int error = cap_capable(cred, ns, cap, audit);
145 if (!error) {
146 profile = aa_cred_profile(cred);
147 if (!unconfined(profile))
148 error = aa_capable(profile, cap, audit);
149 }
150 return error;
151}
152
153/**
154 * common_perm - basic common permission check wrapper fn for paths
155 * @op: operation being checked
156 * @path: path to check permission of (NOT NULL)
157 * @mask: requested permissions mask
158 * @cond: conditional info for the permission request (NOT NULL)
159 *
160 * Returns: %0 else error code if error or permission denied
161 */
162static int common_perm(int op, struct path *path, u32 mask,
163 struct path_cond *cond)
164{
165 struct aa_profile *profile;
166 int error = 0;
167
168 profile = __aa_current_profile();
169 if (!unconfined(profile))
170 error = aa_path_perm(op, profile, path, 0, mask, cond);
171
172 return error;
173}
174
175/**
176 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
177 * @op: operation being checked
178 * @dir: directory of the dentry (NOT NULL)
179 * @dentry: dentry to check (NOT NULL)
180 * @mask: requested permissions mask
181 * @cond: conditional info for the permission request (NOT NULL)
182 *
183 * Returns: %0 else error code if error or permission denied
184 */
185static int common_perm_dir_dentry(int op, struct path *dir,
186 struct dentry *dentry, u32 mask,
187 struct path_cond *cond)
188{
189 struct path path = { dir->mnt, dentry };
190
191 return common_perm(op, &path, mask, cond);
192}
193
194/**
195 * common_perm_mnt_dentry - common permission wrapper when mnt, dentry
196 * @op: operation being checked
197 * @mnt: mount point of dentry (NOT NULL)
198 * @dentry: dentry to check (NOT NULL)
199 * @mask: requested permissions mask
200 *
201 * Returns: %0 else error code if error or permission denied
202 */
203static int common_perm_mnt_dentry(int op, struct vfsmount *mnt,
204 struct dentry *dentry, u32 mask)
205{
206 struct path path = { mnt, dentry };
207 struct path_cond cond = { dentry->d_inode->i_uid,
208 dentry->d_inode->i_mode
209 };
210
211 return common_perm(op, &path, mask, &cond);
212}
213
214/**
215 * common_perm_rm - common permission wrapper for operations doing rm
216 * @op: operation being checked
217 * @dir: directory that the dentry is in (NOT NULL)
218 * @dentry: dentry being rm'd (NOT NULL)
219 * @mask: requested permission mask
220 *
221 * Returns: %0 else error code if error or permission denied
222 */
223static int common_perm_rm(int op, struct path *dir,
224 struct dentry *dentry, u32 mask)
225{
226 struct inode *inode = dentry->d_inode;
227 struct path_cond cond = { };
228
229 if (!inode || !dir->mnt || !mediated_filesystem(inode))
230 return 0;
231
232 cond.uid = inode->i_uid;
233 cond.mode = inode->i_mode;
234
235 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
236}
237
238/**
239 * common_perm_create - common permission wrapper for operations doing create
240 * @op: operation being checked
241 * @dir: directory that dentry will be created in (NOT NULL)
242 * @dentry: dentry to create (NOT NULL)
243 * @mask: request permission mask
244 * @mode: created file mode
245 *
246 * Returns: %0 else error code if error or permission denied
247 */
248static int common_perm_create(int op, struct path *dir, struct dentry *dentry,
249 u32 mask, umode_t mode)
250{
251 struct path_cond cond = { current_fsuid(), mode };
252
253 if (!dir->mnt || !mediated_filesystem(dir->dentry->d_inode))
254 return 0;
255
256 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
257}
258
259static int apparmor_path_unlink(struct path *dir, struct dentry *dentry)
260{
261 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
262}
263
264static int apparmor_path_mkdir(struct path *dir, struct dentry *dentry,
265 umode_t mode)
266{
267 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
268 S_IFDIR);
269}
270
271static int apparmor_path_rmdir(struct path *dir, struct dentry *dentry)
272{
273 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
274}
275
276static int apparmor_path_mknod(struct path *dir, struct dentry *dentry,
277 umode_t mode, unsigned int dev)
278{
279 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
280}
281
282static int apparmor_path_truncate(struct path *path)
283{
284 struct path_cond cond = { path->dentry->d_inode->i_uid,
285 path->dentry->d_inode->i_mode
286 };
287
288 if (!path->mnt || !mediated_filesystem(path->dentry->d_inode))
289 return 0;
290
291 return common_perm(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE,
292 &cond);
293}
294
295static int apparmor_path_symlink(struct path *dir, struct dentry *dentry,
296 const char *old_name)
297{
298 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
299 S_IFLNK);
300}
301
302static int apparmor_path_link(struct dentry *old_dentry, struct path *new_dir,
303 struct dentry *new_dentry)
304{
305 struct aa_profile *profile;
306 int error = 0;
307
308 if (!mediated_filesystem(old_dentry->d_inode))
309 return 0;
310
311 profile = aa_current_profile();
312 if (!unconfined(profile))
313 error = aa_path_link(profile, old_dentry, new_dir, new_dentry);
314 return error;
315}
316
317static int apparmor_path_rename(struct path *old_dir, struct dentry *old_dentry,
318 struct path *new_dir, struct dentry *new_dentry)
319{
320 struct aa_profile *profile;
321 int error = 0;
322
323 if (!mediated_filesystem(old_dentry->d_inode))
324 return 0;
325
326 profile = aa_current_profile();
327 if (!unconfined(profile)) {
328 struct path old_path = { old_dir->mnt, old_dentry };
329 struct path new_path = { new_dir->mnt, new_dentry };
330 struct path_cond cond = { old_dentry->d_inode->i_uid,
331 old_dentry->d_inode->i_mode
332 };
333
334 error = aa_path_perm(OP_RENAME_SRC, profile, &old_path, 0,
335 MAY_READ | AA_MAY_META_READ | MAY_WRITE |
336 AA_MAY_META_WRITE | AA_MAY_DELETE,
337 &cond);
338 if (!error)
339 error = aa_path_perm(OP_RENAME_DEST, profile, &new_path,
340 0, MAY_WRITE | AA_MAY_META_WRITE |
341 AA_MAY_CREATE, &cond);
342
343 }
344 return error;
345}
346
347static int apparmor_path_chmod(struct path *path, umode_t mode)
348{
349 if (!mediated_filesystem(path->dentry->d_inode))
350 return 0;
351
352 return common_perm_mnt_dentry(OP_CHMOD, path->mnt, path->dentry, AA_MAY_CHMOD);
353}
354
355static int apparmor_path_chown(struct path *path, kuid_t uid, kgid_t gid)
356{
357 struct path_cond cond = { path->dentry->d_inode->i_uid,
358 path->dentry->d_inode->i_mode
359 };
360
361 if (!mediated_filesystem(path->dentry->d_inode))
362 return 0;
363
364 return common_perm(OP_CHOWN, path, AA_MAY_CHOWN, &cond);
365}
366
367static int apparmor_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
368{
369 if (!mediated_filesystem(dentry->d_inode))
370 return 0;
371
372 return common_perm_mnt_dentry(OP_GETATTR, mnt, dentry,
373 AA_MAY_META_READ);
374}
375
376static int apparmor_file_open(struct file *file, const struct cred *cred)
377{
378 struct aa_file_cxt *fcxt = file->f_security;
379 struct aa_profile *profile;
380 int error = 0;
381
382 if (!mediated_filesystem(file_inode(file)))
383 return 0;
384
385 /* If in exec, permission is handled by bprm hooks.
386 * Cache permissions granted by the previous exec check, with
387 * implicit read and executable mmap which are required to
388 * actually execute the image.
389 */
390 if (current->in_execve) {
391 fcxt->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
392 return 0;
393 }
394
395 profile = aa_cred_profile(cred);
396 if (!unconfined(profile)) {
397 struct inode *inode = file_inode(file);
398 struct path_cond cond = { inode->i_uid, inode->i_mode };
399
400 error = aa_path_perm(OP_OPEN, profile, &file->f_path, 0,
401 aa_map_file_to_perms(file), &cond);
402 /* todo cache full allowed permissions set and state */
403 fcxt->allow = aa_map_file_to_perms(file);
404 }
405
406 return error;
407}
408
409static int apparmor_file_alloc_security(struct file *file)
410{
411 /* freed by apparmor_file_free_security */
412 file->f_security = aa_alloc_file_context(GFP_KERNEL);
413 if (!file->f_security)
414 return -ENOMEM;
415 return 0;
416
417}
418
419static void apparmor_file_free_security(struct file *file)
420{
421 struct aa_file_cxt *cxt = file->f_security;
422
423 aa_free_file_context(cxt);
424}
425
426static int common_file_perm(int op, struct file *file, u32 mask)
427{
428 struct aa_file_cxt *fcxt = file->f_security;
429 struct aa_profile *profile, *fprofile = aa_cred_profile(file->f_cred);
430 int error = 0;
431
432 BUG_ON(!fprofile);
433
434 if (!file->f_path.mnt ||
435 !mediated_filesystem(file_inode(file)))
436 return 0;
437
438 profile = __aa_current_profile();
439
440 /* revalidate access, if task is unconfined, or the cached cred
441 * doesn't match or if the request is for more permissions than
442 * was granted.
443 *
444 * Note: the test for !unconfined(fprofile) is to handle file
445 * delegation from unconfined tasks
446 */
447 if (!unconfined(profile) && !unconfined(fprofile) &&
448 ((fprofile != profile) || (mask & ~fcxt->allow)))
449 error = aa_file_perm(op, profile, file, mask);
450
451 return error;
452}
453
454static int apparmor_file_permission(struct file *file, int mask)
455{
456 return common_file_perm(OP_FPERM, file, mask);
457}
458
459static int apparmor_file_lock(struct file *file, unsigned int cmd)
460{
461 u32 mask = AA_MAY_LOCK;
462
463 if (cmd == F_WRLCK)
464 mask |= MAY_WRITE;
465
466 return common_file_perm(OP_FLOCK, file, mask);
467}
468
469static int common_mmap(int op, struct file *file, unsigned long prot,
470 unsigned long flags)
471{
472 int mask = 0;
473
474 if (!file || !file->f_security)
475 return 0;
476
477 if (prot & PROT_READ)
478 mask |= MAY_READ;
479 /*
480 * Private mappings don't require write perms since they don't
481 * write back to the files
482 */
483 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
484 mask |= MAY_WRITE;
485 if (prot & PROT_EXEC)
486 mask |= AA_EXEC_MMAP;
487
488 return common_file_perm(op, file, mask);
489}
490
491static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
492 unsigned long prot, unsigned long flags)
493{
494 return common_mmap(OP_FMMAP, file, prot, flags);
495}
496
497static int apparmor_file_mprotect(struct vm_area_struct *vma,
498 unsigned long reqprot, unsigned long prot)
499{
500 return common_mmap(OP_FMPROT, vma->vm_file, prot,
501 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
502}
503
504static int apparmor_getprocattr(struct task_struct *task, char *name,
505 char **value)
506{
507 int error = -ENOENT;
508 /* released below */
509 const struct cred *cred = get_task_cred(task);
510 struct aa_task_cxt *cxt = cred_cxt(cred);
511 struct aa_profile *profile = NULL;
512
513 if (strcmp(name, "current") == 0)
514 profile = aa_get_newest_profile(cxt->profile);
515 else if (strcmp(name, "prev") == 0 && cxt->previous)
516 profile = aa_get_newest_profile(cxt->previous);
517 else if (strcmp(name, "exec") == 0 && cxt->onexec)
518 profile = aa_get_newest_profile(cxt->onexec);
519 else
520 error = -EINVAL;
521
522 if (profile)
523 error = aa_getprocattr(profile, value);
524
525 aa_put_profile(profile);
526 put_cred(cred);
527
528 return error;
529}
530
531static int apparmor_setprocattr(struct task_struct *task, char *name,
532 void *value, size_t size)
533{
534 struct common_audit_data sa;
535 struct apparmor_audit_data aad = {0,};
536 char *command, *args = value;
537 size_t arg_size;
538 int error;
539
540 if (size == 0)
541 return -EINVAL;
542 /* args points to a PAGE_SIZE buffer, AppArmor requires that
543 * the buffer must be null terminated or have size <= PAGE_SIZE -1
544 * so that AppArmor can null terminate them
545 */
546 if (args[size - 1] != '\0') {
547 if (size == PAGE_SIZE)
548 return -EINVAL;
549 args[size] = '\0';
550 }
551
552 /* task can only write its own attributes */
553 if (current != task)
554 return -EACCES;
555
556 args = value;
557 args = strim(args);
558 command = strsep(&args, " ");
559 if (!args)
560 return -EINVAL;
561 args = skip_spaces(args);
562 if (!*args)
563 return -EINVAL;
564
565 arg_size = size - (args - (char *) value);
566 if (strcmp(name, "current") == 0) {
567 if (strcmp(command, "changehat") == 0) {
568 error = aa_setprocattr_changehat(args, arg_size,
569 !AA_DO_TEST);
570 } else if (strcmp(command, "permhat") == 0) {
571 error = aa_setprocattr_changehat(args, arg_size,
572 AA_DO_TEST);
573 } else if (strcmp(command, "changeprofile") == 0) {
574 error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
575 !AA_DO_TEST);
576 } else if (strcmp(command, "permprofile") == 0) {
577 error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
578 AA_DO_TEST);
579 } else
580 goto fail;
581 } else if (strcmp(name, "exec") == 0) {
582 if (strcmp(command, "exec") == 0)
583 error = aa_setprocattr_changeprofile(args, AA_ONEXEC,
584 !AA_DO_TEST);
585 else
586 goto fail;
587 } else
588 /* only support the "current" and "exec" process attributes */
589 return -EINVAL;
590
591 if (!error)
592 error = size;
593 return error;
594
595fail:
596 sa.type = LSM_AUDIT_DATA_NONE;
597 sa.aad = &aad;
598 aad.profile = aa_current_profile();
599 aad.op = OP_SETPROCATTR;
600 aad.info = name;
601 aad.error = -EINVAL;
602 aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
603 return -EINVAL;
604}
605
606static int apparmor_task_setrlimit(struct task_struct *task,
607 unsigned int resource, struct rlimit *new_rlim)
608{
609 struct aa_profile *profile = __aa_current_profile();
610 int error = 0;
611
612 if (!unconfined(profile))
613 error = aa_task_setrlimit(profile, task, resource, new_rlim);
614
615 return error;
616}
617
618static struct security_operations apparmor_ops = {
619 .name = "apparmor",
620
621 .ptrace_access_check = apparmor_ptrace_access_check,
622 .ptrace_traceme = apparmor_ptrace_traceme,
623 .capget = apparmor_capget,
624 .capable = apparmor_capable,
625
626 .path_link = apparmor_path_link,
627 .path_unlink = apparmor_path_unlink,
628 .path_symlink = apparmor_path_symlink,
629 .path_mkdir = apparmor_path_mkdir,
630 .path_rmdir = apparmor_path_rmdir,
631 .path_mknod = apparmor_path_mknod,
632 .path_rename = apparmor_path_rename,
633 .path_chmod = apparmor_path_chmod,
634 .path_chown = apparmor_path_chown,
635 .path_truncate = apparmor_path_truncate,
636 .inode_getattr = apparmor_inode_getattr,
637
638 .file_open = apparmor_file_open,
639 .file_permission = apparmor_file_permission,
640 .file_alloc_security = apparmor_file_alloc_security,
641 .file_free_security = apparmor_file_free_security,
642 .mmap_file = apparmor_mmap_file,
643 .mmap_addr = cap_mmap_addr,
644 .file_mprotect = apparmor_file_mprotect,
645 .file_lock = apparmor_file_lock,
646
647 .getprocattr = apparmor_getprocattr,
648 .setprocattr = apparmor_setprocattr,
649
650 .cred_alloc_blank = apparmor_cred_alloc_blank,
651 .cred_free = apparmor_cred_free,
652 .cred_prepare = apparmor_cred_prepare,
653 .cred_transfer = apparmor_cred_transfer,
654
655 .bprm_set_creds = apparmor_bprm_set_creds,
656 .bprm_committing_creds = apparmor_bprm_committing_creds,
657 .bprm_committed_creds = apparmor_bprm_committed_creds,
658 .bprm_secureexec = apparmor_bprm_secureexec,
659
660 .task_setrlimit = apparmor_task_setrlimit,
661};
662
663/*
664 * AppArmor sysfs module parameters
665 */
666
667static int param_set_aabool(const char *val, const struct kernel_param *kp);
668static int param_get_aabool(char *buffer, const struct kernel_param *kp);
669#define param_check_aabool param_check_bool
670static struct kernel_param_ops param_ops_aabool = {
671 .flags = KERNEL_PARAM_FL_NOARG,
672 .set = param_set_aabool,
673 .get = param_get_aabool
674};
675
676static int param_set_aauint(const char *val, const struct kernel_param *kp);
677static int param_get_aauint(char *buffer, const struct kernel_param *kp);
678#define param_check_aauint param_check_uint
679static struct kernel_param_ops param_ops_aauint = {
680 .set = param_set_aauint,
681 .get = param_get_aauint
682};
683
684static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
685static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
686#define param_check_aalockpolicy param_check_bool
687static struct kernel_param_ops param_ops_aalockpolicy = {
688 .flags = KERNEL_PARAM_FL_NOARG,
689 .set = param_set_aalockpolicy,
690 .get = param_get_aalockpolicy
691};
692
693static int param_set_audit(const char *val, struct kernel_param *kp);
694static int param_get_audit(char *buffer, struct kernel_param *kp);
695
696static int param_set_mode(const char *val, struct kernel_param *kp);
697static int param_get_mode(char *buffer, struct kernel_param *kp);
698
699/* Flag values, also controllable via /sys/module/apparmor/parameters
700 * We define special types as we want to do additional mediation.
701 */
702
703/* AppArmor global enforcement switch - complain, enforce, kill */
704enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
705module_param_call(mode, param_set_mode, param_get_mode,
706 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
707
708/* Debug mode */
709bool aa_g_debug;
710module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
711
712/* Audit mode */
713enum audit_mode aa_g_audit;
714module_param_call(audit, param_set_audit, param_get_audit,
715 &aa_g_audit, S_IRUSR | S_IWUSR);
716
717/* Determines if audit header is included in audited messages. This
718 * provides more context if the audit daemon is not running
719 */
720bool aa_g_audit_header = 1;
721module_param_named(audit_header, aa_g_audit_header, aabool,
722 S_IRUSR | S_IWUSR);
723
724/* lock out loading/removal of policy
725 * TODO: add in at boot loading of policy, which is the only way to
726 * load policy, if lock_policy is set
727 */
728bool aa_g_lock_policy;
729module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
730 S_IRUSR | S_IWUSR);
731
732/* Syscall logging mode */
733bool aa_g_logsyscall;
734module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
735
736/* Maximum pathname length before accesses will start getting rejected */
737unsigned int aa_g_path_max = 2 * PATH_MAX;
738module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR | S_IWUSR);
739
740/* Determines how paranoid loading of policy is and how much verification
741 * on the loaded policy is done.
742 */
743bool aa_g_paranoid_load = 1;
744module_param_named(paranoid_load, aa_g_paranoid_load, aabool,
745 S_IRUSR | S_IWUSR);
746
747/* Boot time disable flag */
748static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
749module_param_named(enabled, apparmor_enabled, bool, S_IRUGO);
750
751static int __init apparmor_enabled_setup(char *str)
752{
753 unsigned long enabled;
754 int error = kstrtoul(str, 0, &enabled);
755 if (!error)
756 apparmor_enabled = enabled ? 1 : 0;
757 return 1;
758}
759
760__setup("apparmor=", apparmor_enabled_setup);
761
762/* set global flag turning off the ability to load policy */
763static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
764{
765 if (!capable(CAP_MAC_ADMIN))
766 return -EPERM;
767 if (aa_g_lock_policy)
768 return -EACCES;
769 return param_set_bool(val, kp);
770}
771
772static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
773{
774 if (!capable(CAP_MAC_ADMIN))
775 return -EPERM;
776 return param_get_bool(buffer, kp);
777}
778
779static int param_set_aabool(const char *val, const struct kernel_param *kp)
780{
781 if (!capable(CAP_MAC_ADMIN))
782 return -EPERM;
783 return param_set_bool(val, kp);
784}
785
786static int param_get_aabool(char *buffer, const struct kernel_param *kp)
787{
788 if (!capable(CAP_MAC_ADMIN))
789 return -EPERM;
790 return param_get_bool(buffer, kp);
791}
792
793static int param_set_aauint(const char *val, const struct kernel_param *kp)
794{
795 if (!capable(CAP_MAC_ADMIN))
796 return -EPERM;
797 return param_set_uint(val, kp);
798}
799
800static int param_get_aauint(char *buffer, const struct kernel_param *kp)
801{
802 if (!capable(CAP_MAC_ADMIN))
803 return -EPERM;
804 return param_get_uint(buffer, kp);
805}
806
807static int param_get_audit(char *buffer, struct kernel_param *kp)
808{
809 if (!capable(CAP_MAC_ADMIN))
810 return -EPERM;
811
812 if (!apparmor_enabled)
813 return -EINVAL;
814
815 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
816}
817
818static int param_set_audit(const char *val, struct kernel_param *kp)
819{
820 int i;
821 if (!capable(CAP_MAC_ADMIN))
822 return -EPERM;
823
824 if (!apparmor_enabled)
825 return -EINVAL;
826
827 if (!val)
828 return -EINVAL;
829
830 for (i = 0; i < AUDIT_MAX_INDEX; i++) {
831 if (strcmp(val, audit_mode_names[i]) == 0) {
832 aa_g_audit = i;
833 return 0;
834 }
835 }
836
837 return -EINVAL;
838}
839
840static int param_get_mode(char *buffer, struct kernel_param *kp)
841{
842 if (!capable(CAP_MAC_ADMIN))
843 return -EPERM;
844
845 if (!apparmor_enabled)
846 return -EINVAL;
847
848 return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
849}
850
851static int param_set_mode(const char *val, struct kernel_param *kp)
852{
853 int i;
854 if (!capable(CAP_MAC_ADMIN))
855 return -EPERM;
856
857 if (!apparmor_enabled)
858 return -EINVAL;
859
860 if (!val)
861 return -EINVAL;
862
863 for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) {
864 if (strcmp(val, aa_profile_mode_names[i]) == 0) {
865 aa_g_profile_mode = i;
866 return 0;
867 }
868 }
869
870 return -EINVAL;
871}
872
873/*
874 * AppArmor init functions
875 */
876
877/**
878 * set_init_cxt - set a task context and profile on the first task.
879 *
880 * TODO: allow setting an alternate profile than unconfined
881 */
882static int __init set_init_cxt(void)
883{
884 struct cred *cred = (struct cred *)current->real_cred;
885 struct aa_task_cxt *cxt;
886
887 cxt = aa_alloc_task_context(GFP_KERNEL);
888 if (!cxt)
889 return -ENOMEM;
890
891 cxt->profile = aa_get_profile(root_ns->unconfined);
892 cred_cxt(cred) = cxt;
893
894 return 0;
895}
896
897static int __init apparmor_init(void)
898{
899 int error;
900
901 if (!apparmor_enabled || !security_module_enable(&apparmor_ops)) {
902 aa_info_message("AppArmor disabled by boot time parameter");
903 apparmor_enabled = 0;
904 return 0;
905 }
906
907 error = aa_alloc_root_ns();
908 if (error) {
909 AA_ERROR("Unable to allocate default profile namespace\n");
910 goto alloc_out;
911 }
912
913 error = set_init_cxt();
914 if (error) {
915 AA_ERROR("Failed to set context on init task\n");
916 goto register_security_out;
917 }
918
919 error = register_security(&apparmor_ops);
920 if (error) {
921 struct cred *cred = (struct cred *)current->real_cred;
922 aa_free_task_context(cred_cxt(cred));
923 cred_cxt(cred) = NULL;
924 AA_ERROR("Unable to register AppArmor\n");
925 goto register_security_out;
926 }
927
928 /* Report that AppArmor successfully initialized */
929 apparmor_initialized = 1;
930 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
931 aa_info_message("AppArmor initialized: complain mode enabled");
932 else if (aa_g_profile_mode == APPARMOR_KILL)
933 aa_info_message("AppArmor initialized: kill mode enabled");
934 else
935 aa_info_message("AppArmor initialized");
936
937 return error;
938
939register_security_out:
940 aa_free_root_ns();
941
942alloc_out:
943 aa_destroy_aafs();
944
945 apparmor_enabled = 0;
946 return error;
947}
948
949security_initcall(apparmor_init);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor LSM hooks.
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 */
10
11#include <linux/lsm_hooks.h>
12#include <linux/moduleparam.h>
13#include <linux/mm.h>
14#include <linux/mman.h>
15#include <linux/mount.h>
16#include <linux/namei.h>
17#include <linux/ptrace.h>
18#include <linux/ctype.h>
19#include <linux/sysctl.h>
20#include <linux/audit.h>
21#include <linux/user_namespace.h>
22#include <linux/netfilter_ipv4.h>
23#include <linux/netfilter_ipv6.h>
24#include <linux/zstd.h>
25#include <net/sock.h>
26#include <uapi/linux/mount.h>
27#include <uapi/linux/lsm.h>
28
29#include "include/apparmor.h"
30#include "include/apparmorfs.h"
31#include "include/audit.h"
32#include "include/capability.h"
33#include "include/cred.h"
34#include "include/file.h"
35#include "include/ipc.h"
36#include "include/net.h"
37#include "include/path.h"
38#include "include/label.h"
39#include "include/policy.h"
40#include "include/policy_ns.h"
41#include "include/procattr.h"
42#include "include/mount.h"
43#include "include/secid.h"
44
45/* Flag indicating whether initialization completed */
46int apparmor_initialized;
47
48union aa_buffer {
49 struct list_head list;
50 DECLARE_FLEX_ARRAY(char, buffer);
51};
52
53struct aa_local_cache {
54 unsigned int hold;
55 unsigned int count;
56 struct list_head head;
57};
58
59#define RESERVE_COUNT 2
60static int reserve_count = RESERVE_COUNT;
61static int buffer_count;
62
63static LIST_HEAD(aa_global_buffers);
64static DEFINE_SPINLOCK(aa_buffers_lock);
65static DEFINE_PER_CPU(struct aa_local_cache, aa_local_buffers);
66
67/*
68 * LSM hook functions
69 */
70
71/*
72 * put the associated labels
73 */
74static void apparmor_cred_free(struct cred *cred)
75{
76 aa_put_label(cred_label(cred));
77 set_cred_label(cred, NULL);
78}
79
80/*
81 * allocate the apparmor part of blank credentials
82 */
83static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
84{
85 set_cred_label(cred, NULL);
86 return 0;
87}
88
89/*
90 * prepare new cred label for modification by prepare_cred block
91 */
92static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
93 gfp_t gfp)
94{
95 set_cred_label(new, aa_get_newest_label(cred_label(old)));
96 return 0;
97}
98
99/*
100 * transfer the apparmor data to a blank set of creds
101 */
102static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
103{
104 set_cred_label(new, aa_get_newest_label(cred_label(old)));
105}
106
107static void apparmor_task_free(struct task_struct *task)
108{
109
110 aa_free_task_ctx(task_ctx(task));
111}
112
113static int apparmor_task_alloc(struct task_struct *task,
114 unsigned long clone_flags)
115{
116 struct aa_task_ctx *new = task_ctx(task);
117
118 aa_dup_task_ctx(new, task_ctx(current));
119
120 return 0;
121}
122
123static int apparmor_ptrace_access_check(struct task_struct *child,
124 unsigned int mode)
125{
126 struct aa_label *tracer, *tracee;
127 const struct cred *cred;
128 int error;
129
130 cred = get_task_cred(child);
131 tracee = cred_label(cred); /* ref count on cred */
132 tracer = __begin_current_label_crit_section();
133 error = aa_may_ptrace(current_cred(), tracer, cred, tracee,
134 (mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
135 : AA_PTRACE_TRACE);
136 __end_current_label_crit_section(tracer);
137 put_cred(cred);
138
139 return error;
140}
141
142static int apparmor_ptrace_traceme(struct task_struct *parent)
143{
144 struct aa_label *tracer, *tracee;
145 const struct cred *cred;
146 int error;
147
148 tracee = __begin_current_label_crit_section();
149 cred = get_task_cred(parent);
150 tracer = cred_label(cred); /* ref count on cred */
151 error = aa_may_ptrace(cred, tracer, current_cred(), tracee,
152 AA_PTRACE_TRACE);
153 put_cred(cred);
154 __end_current_label_crit_section(tracee);
155
156 return error;
157}
158
159/* Derived from security/commoncap.c:cap_capget */
160static int apparmor_capget(const struct task_struct *target, kernel_cap_t *effective,
161 kernel_cap_t *inheritable, kernel_cap_t *permitted)
162{
163 struct aa_label *label;
164 const struct cred *cred;
165
166 rcu_read_lock();
167 cred = __task_cred(target);
168 label = aa_get_newest_cred_label(cred);
169
170 /*
171 * cap_capget is stacked ahead of this and will
172 * initialize effective and permitted.
173 */
174 if (!unconfined(label)) {
175 struct aa_profile *profile;
176 struct label_it i;
177
178 label_for_each_confined(i, label, profile) {
179 struct aa_ruleset *rules;
180 if (COMPLAIN_MODE(profile))
181 continue;
182 rules = list_first_entry(&profile->rules,
183 typeof(*rules), list);
184 *effective = cap_intersect(*effective,
185 rules->caps.allow);
186 *permitted = cap_intersect(*permitted,
187 rules->caps.allow);
188 }
189 }
190 rcu_read_unlock();
191 aa_put_label(label);
192
193 return 0;
194}
195
196static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
197 int cap, unsigned int opts)
198{
199 struct aa_label *label;
200 int error = 0;
201
202 label = aa_get_newest_cred_label(cred);
203 if (!unconfined(label))
204 error = aa_capable(cred, label, cap, opts);
205 aa_put_label(label);
206
207 return error;
208}
209
210/**
211 * common_perm - basic common permission check wrapper fn for paths
212 * @op: operation being checked
213 * @path: path to check permission of (NOT NULL)
214 * @mask: requested permissions mask
215 * @cond: conditional info for the permission request (NOT NULL)
216 *
217 * Returns: %0 else error code if error or permission denied
218 */
219static int common_perm(const char *op, const struct path *path, u32 mask,
220 struct path_cond *cond)
221{
222 struct aa_label *label;
223 int error = 0;
224
225 label = __begin_current_label_crit_section();
226 if (!unconfined(label))
227 error = aa_path_perm(op, current_cred(), label, path, 0, mask,
228 cond);
229 __end_current_label_crit_section(label);
230
231 return error;
232}
233
234/**
235 * common_perm_cond - common permission wrapper around inode cond
236 * @op: operation being checked
237 * @path: location to check (NOT NULL)
238 * @mask: requested permissions mask
239 *
240 * Returns: %0 else error code if error or permission denied
241 */
242static int common_perm_cond(const char *op, const struct path *path, u32 mask)
243{
244 vfsuid_t vfsuid = i_uid_into_vfsuid(mnt_idmap(path->mnt),
245 d_backing_inode(path->dentry));
246 struct path_cond cond = {
247 vfsuid_into_kuid(vfsuid),
248 d_backing_inode(path->dentry)->i_mode
249 };
250
251 if (!path_mediated_fs(path->dentry))
252 return 0;
253
254 return common_perm(op, path, mask, &cond);
255}
256
257/**
258 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
259 * @op: operation being checked
260 * @dir: directory of the dentry (NOT NULL)
261 * @dentry: dentry to check (NOT NULL)
262 * @mask: requested permissions mask
263 * @cond: conditional info for the permission request (NOT NULL)
264 *
265 * Returns: %0 else error code if error or permission denied
266 */
267static int common_perm_dir_dentry(const char *op, const struct path *dir,
268 struct dentry *dentry, u32 mask,
269 struct path_cond *cond)
270{
271 struct path path = { .mnt = dir->mnt, .dentry = dentry };
272
273 return common_perm(op, &path, mask, cond);
274}
275
276/**
277 * common_perm_rm - common permission wrapper for operations doing rm
278 * @op: operation being checked
279 * @dir: directory that the dentry is in (NOT NULL)
280 * @dentry: dentry being rm'd (NOT NULL)
281 * @mask: requested permission mask
282 *
283 * Returns: %0 else error code if error or permission denied
284 */
285static int common_perm_rm(const char *op, const struct path *dir,
286 struct dentry *dentry, u32 mask)
287{
288 struct inode *inode = d_backing_inode(dentry);
289 struct path_cond cond = { };
290 vfsuid_t vfsuid;
291
292 if (!inode || !path_mediated_fs(dentry))
293 return 0;
294
295 vfsuid = i_uid_into_vfsuid(mnt_idmap(dir->mnt), inode);
296 cond.uid = vfsuid_into_kuid(vfsuid);
297 cond.mode = inode->i_mode;
298
299 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
300}
301
302/**
303 * common_perm_create - common permission wrapper for operations doing create
304 * @op: operation being checked
305 * @dir: directory that dentry will be created in (NOT NULL)
306 * @dentry: dentry to create (NOT NULL)
307 * @mask: request permission mask
308 * @mode: created file mode
309 *
310 * Returns: %0 else error code if error or permission denied
311 */
312static int common_perm_create(const char *op, const struct path *dir,
313 struct dentry *dentry, u32 mask, umode_t mode)
314{
315 struct path_cond cond = { current_fsuid(), mode };
316
317 if (!path_mediated_fs(dir->dentry))
318 return 0;
319
320 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
321}
322
323static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
324{
325 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
326}
327
328static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
329 umode_t mode)
330{
331 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
332 S_IFDIR);
333}
334
335static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
336{
337 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
338}
339
340static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
341 umode_t mode, unsigned int dev)
342{
343 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
344}
345
346static int apparmor_path_truncate(const struct path *path)
347{
348 return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
349}
350
351static int apparmor_file_truncate(struct file *file)
352{
353 return apparmor_path_truncate(&file->f_path);
354}
355
356static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
357 const char *old_name)
358{
359 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
360 S_IFLNK);
361}
362
363static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
364 struct dentry *new_dentry)
365{
366 struct aa_label *label;
367 int error = 0;
368
369 if (!path_mediated_fs(old_dentry))
370 return 0;
371
372 label = begin_current_label_crit_section();
373 if (!unconfined(label))
374 error = aa_path_link(current_cred(), label, old_dentry, new_dir,
375 new_dentry);
376 end_current_label_crit_section(label);
377
378 return error;
379}
380
381static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
382 const struct path *new_dir, struct dentry *new_dentry,
383 const unsigned int flags)
384{
385 struct aa_label *label;
386 int error = 0;
387
388 if (!path_mediated_fs(old_dentry))
389 return 0;
390 if ((flags & RENAME_EXCHANGE) && !path_mediated_fs(new_dentry))
391 return 0;
392
393 label = begin_current_label_crit_section();
394 if (!unconfined(label)) {
395 struct mnt_idmap *idmap = mnt_idmap(old_dir->mnt);
396 vfsuid_t vfsuid;
397 struct path old_path = { .mnt = old_dir->mnt,
398 .dentry = old_dentry };
399 struct path new_path = { .mnt = new_dir->mnt,
400 .dentry = new_dentry };
401 struct path_cond cond = {
402 .mode = d_backing_inode(old_dentry)->i_mode
403 };
404 vfsuid = i_uid_into_vfsuid(idmap, d_backing_inode(old_dentry));
405 cond.uid = vfsuid_into_kuid(vfsuid);
406
407 if (flags & RENAME_EXCHANGE) {
408 struct path_cond cond_exchange = {
409 .mode = d_backing_inode(new_dentry)->i_mode,
410 };
411 vfsuid = i_uid_into_vfsuid(idmap, d_backing_inode(old_dentry));
412 cond_exchange.uid = vfsuid_into_kuid(vfsuid);
413
414 error = aa_path_perm(OP_RENAME_SRC, current_cred(),
415 label, &new_path, 0,
416 MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
417 AA_MAY_SETATTR | AA_MAY_DELETE,
418 &cond_exchange);
419 if (!error)
420 error = aa_path_perm(OP_RENAME_DEST, current_cred(),
421 label, &old_path,
422 0, MAY_WRITE | AA_MAY_SETATTR |
423 AA_MAY_CREATE, &cond_exchange);
424 }
425
426 if (!error)
427 error = aa_path_perm(OP_RENAME_SRC, current_cred(),
428 label, &old_path, 0,
429 MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
430 AA_MAY_SETATTR | AA_MAY_DELETE,
431 &cond);
432 if (!error)
433 error = aa_path_perm(OP_RENAME_DEST, current_cred(),
434 label, &new_path,
435 0, MAY_WRITE | AA_MAY_SETATTR |
436 AA_MAY_CREATE, &cond);
437
438 }
439 end_current_label_crit_section(label);
440
441 return error;
442}
443
444static int apparmor_path_chmod(const struct path *path, umode_t mode)
445{
446 return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
447}
448
449static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
450{
451 return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
452}
453
454static int apparmor_inode_getattr(const struct path *path)
455{
456 return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
457}
458
459static int apparmor_file_open(struct file *file)
460{
461 struct aa_file_ctx *fctx = file_ctx(file);
462 struct aa_label *label;
463 int error = 0;
464
465 if (!path_mediated_fs(file->f_path.dentry))
466 return 0;
467
468 /* If in exec, permission is handled by bprm hooks.
469 * Cache permissions granted by the previous exec check, with
470 * implicit read and executable mmap which are required to
471 * actually execute the image.
472 *
473 * Illogically, FMODE_EXEC is in f_flags, not f_mode.
474 */
475 if (file->f_flags & __FMODE_EXEC) {
476 fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
477 return 0;
478 }
479
480 label = aa_get_newest_cred_label(file->f_cred);
481 if (!unconfined(label)) {
482 struct mnt_idmap *idmap = file_mnt_idmap(file);
483 struct inode *inode = file_inode(file);
484 vfsuid_t vfsuid;
485 struct path_cond cond = {
486 .mode = inode->i_mode,
487 };
488 vfsuid = i_uid_into_vfsuid(idmap, inode);
489 cond.uid = vfsuid_into_kuid(vfsuid);
490
491 error = aa_path_perm(OP_OPEN, file->f_cred,
492 label, &file->f_path, 0,
493 aa_map_file_to_perms(file), &cond);
494 /* todo cache full allowed permissions set and state */
495 fctx->allow = aa_map_file_to_perms(file);
496 }
497 aa_put_label(label);
498
499 return error;
500}
501
502static int apparmor_file_alloc_security(struct file *file)
503{
504 struct aa_file_ctx *ctx = file_ctx(file);
505 struct aa_label *label = begin_current_label_crit_section();
506
507 spin_lock_init(&ctx->lock);
508 rcu_assign_pointer(ctx->label, aa_get_label(label));
509 end_current_label_crit_section(label);
510 return 0;
511}
512
513static void apparmor_file_free_security(struct file *file)
514{
515 struct aa_file_ctx *ctx = file_ctx(file);
516
517 if (ctx)
518 aa_put_label(rcu_access_pointer(ctx->label));
519}
520
521static int common_file_perm(const char *op, struct file *file, u32 mask,
522 bool in_atomic)
523{
524 struct aa_label *label;
525 int error = 0;
526
527 /* don't reaudit files closed during inheritance */
528 if (file->f_path.dentry == aa_null.dentry)
529 return -EACCES;
530
531 label = __begin_current_label_crit_section();
532 error = aa_file_perm(op, current_cred(), label, file, mask, in_atomic);
533 __end_current_label_crit_section(label);
534
535 return error;
536}
537
538static int apparmor_file_receive(struct file *file)
539{
540 return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file),
541 false);
542}
543
544static int apparmor_file_permission(struct file *file, int mask)
545{
546 return common_file_perm(OP_FPERM, file, mask, false);
547}
548
549static int apparmor_file_lock(struct file *file, unsigned int cmd)
550{
551 u32 mask = AA_MAY_LOCK;
552
553 if (cmd == F_WRLCK)
554 mask |= MAY_WRITE;
555
556 return common_file_perm(OP_FLOCK, file, mask, false);
557}
558
559static int common_mmap(const char *op, struct file *file, unsigned long prot,
560 unsigned long flags, bool in_atomic)
561{
562 int mask = 0;
563
564 if (!file || !file_ctx(file))
565 return 0;
566
567 if (prot & PROT_READ)
568 mask |= MAY_READ;
569 /*
570 * Private mappings don't require write perms since they don't
571 * write back to the files
572 */
573 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
574 mask |= MAY_WRITE;
575 if (prot & PROT_EXEC)
576 mask |= AA_EXEC_MMAP;
577
578 return common_file_perm(op, file, mask, in_atomic);
579}
580
581static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
582 unsigned long prot, unsigned long flags)
583{
584 return common_mmap(OP_FMMAP, file, prot, flags, GFP_ATOMIC);
585}
586
587static int apparmor_file_mprotect(struct vm_area_struct *vma,
588 unsigned long reqprot, unsigned long prot)
589{
590 return common_mmap(OP_FMPROT, vma->vm_file, prot,
591 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0,
592 false);
593}
594
595#ifdef CONFIG_IO_URING
596static const char *audit_uring_mask(u32 mask)
597{
598 if (mask & AA_MAY_CREATE_SQPOLL)
599 return "sqpoll";
600 if (mask & AA_MAY_OVERRIDE_CRED)
601 return "override_creds";
602 return "";
603}
604
605static void audit_uring_cb(struct audit_buffer *ab, void *va)
606{
607 struct apparmor_audit_data *ad = aad_of_va(va);
608
609 if (ad->request & AA_URING_PERM_MASK) {
610 audit_log_format(ab, " requested=\"%s\"",
611 audit_uring_mask(ad->request));
612 if (ad->denied & AA_URING_PERM_MASK) {
613 audit_log_format(ab, " denied=\"%s\"",
614 audit_uring_mask(ad->denied));
615 }
616 }
617 if (ad->uring.target) {
618 audit_log_format(ab, " tcontext=");
619 aa_label_xaudit(ab, labels_ns(ad->subj_label),
620 ad->uring.target,
621 FLAGS_NONE, GFP_ATOMIC);
622 }
623}
624
625static int profile_uring(struct aa_profile *profile, u32 request,
626 struct aa_label *new, int cap,
627 struct apparmor_audit_data *ad)
628{
629 unsigned int state;
630 struct aa_ruleset *rules;
631 int error = 0;
632
633 AA_BUG(!profile);
634
635 rules = list_first_entry(&profile->rules, typeof(*rules), list);
636 state = RULE_MEDIATES(rules, AA_CLASS_IO_URING);
637 if (state) {
638 struct aa_perms perms = { };
639
640 if (new) {
641 aa_label_match(profile, rules, new, state,
642 false, request, &perms);
643 } else {
644 perms = *aa_lookup_perms(rules->policy, state);
645 }
646 aa_apply_modes_to_perms(profile, &perms);
647 error = aa_check_perms(profile, &perms, request, ad,
648 audit_uring_cb);
649 }
650
651 return error;
652}
653
654/**
655 * apparmor_uring_override_creds - check the requested cred override
656 * @new: the target creds
657 *
658 * Check to see if the current task is allowed to override it's credentials
659 * to service an io_uring operation.
660 */
661static int apparmor_uring_override_creds(const struct cred *new)
662{
663 struct aa_profile *profile;
664 struct aa_label *label;
665 int error;
666 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_IO_URING,
667 OP_URING_OVERRIDE);
668
669 ad.uring.target = cred_label(new);
670 label = __begin_current_label_crit_section();
671 error = fn_for_each(label, profile,
672 profile_uring(profile, AA_MAY_OVERRIDE_CRED,
673 cred_label(new), CAP_SYS_ADMIN, &ad));
674 __end_current_label_crit_section(label);
675
676 return error;
677}
678
679/**
680 * apparmor_uring_sqpoll - check if a io_uring polling thread can be created
681 *
682 * Check to see if the current task is allowed to create a new io_uring
683 * kernel polling thread.
684 */
685static int apparmor_uring_sqpoll(void)
686{
687 struct aa_profile *profile;
688 struct aa_label *label;
689 int error;
690 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_IO_URING,
691 OP_URING_SQPOLL);
692
693 label = __begin_current_label_crit_section();
694 error = fn_for_each(label, profile,
695 profile_uring(profile, AA_MAY_CREATE_SQPOLL,
696 NULL, CAP_SYS_ADMIN, &ad));
697 __end_current_label_crit_section(label);
698
699 return error;
700}
701#endif /* CONFIG_IO_URING */
702
703static int apparmor_sb_mount(const char *dev_name, const struct path *path,
704 const char *type, unsigned long flags, void *data)
705{
706 struct aa_label *label;
707 int error = 0;
708
709 /* Discard magic */
710 if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
711 flags &= ~MS_MGC_MSK;
712
713 flags &= ~AA_MS_IGNORE_MASK;
714
715 label = __begin_current_label_crit_section();
716 if (!unconfined(label)) {
717 if (flags & MS_REMOUNT)
718 error = aa_remount(current_cred(), label, path, flags,
719 data);
720 else if (flags & MS_BIND)
721 error = aa_bind_mount(current_cred(), label, path,
722 dev_name, flags);
723 else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
724 MS_UNBINDABLE))
725 error = aa_mount_change_type(current_cred(), label,
726 path, flags);
727 else if (flags & MS_MOVE)
728 error = aa_move_mount_old(current_cred(), label, path,
729 dev_name);
730 else
731 error = aa_new_mount(current_cred(), label, dev_name,
732 path, type, flags, data);
733 }
734 __end_current_label_crit_section(label);
735
736 return error;
737}
738
739static int apparmor_move_mount(const struct path *from_path,
740 const struct path *to_path)
741{
742 struct aa_label *label;
743 int error = 0;
744
745 label = __begin_current_label_crit_section();
746 if (!unconfined(label))
747 error = aa_move_mount(current_cred(), label, from_path,
748 to_path);
749 __end_current_label_crit_section(label);
750
751 return error;
752}
753
754static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
755{
756 struct aa_label *label;
757 int error = 0;
758
759 label = __begin_current_label_crit_section();
760 if (!unconfined(label))
761 error = aa_umount(current_cred(), label, mnt, flags);
762 __end_current_label_crit_section(label);
763
764 return error;
765}
766
767static int apparmor_sb_pivotroot(const struct path *old_path,
768 const struct path *new_path)
769{
770 struct aa_label *label;
771 int error = 0;
772
773 label = aa_get_current_label();
774 if (!unconfined(label))
775 error = aa_pivotroot(current_cred(), label, old_path, new_path);
776 aa_put_label(label);
777
778 return error;
779}
780
781static int apparmor_getselfattr(unsigned int attr, struct lsm_ctx __user *lx,
782 size_t *size, u32 flags)
783{
784 int error = -ENOENT;
785 struct aa_task_ctx *ctx = task_ctx(current);
786 struct aa_label *label = NULL;
787 char *value = NULL;
788
789 switch (attr) {
790 case LSM_ATTR_CURRENT:
791 label = aa_get_newest_label(cred_label(current_cred()));
792 break;
793 case LSM_ATTR_PREV:
794 if (ctx->previous)
795 label = aa_get_newest_label(ctx->previous);
796 break;
797 case LSM_ATTR_EXEC:
798 if (ctx->onexec)
799 label = aa_get_newest_label(ctx->onexec);
800 break;
801 default:
802 error = -EOPNOTSUPP;
803 break;
804 }
805
806 if (label) {
807 error = aa_getprocattr(label, &value, false);
808 if (error > 0)
809 error = lsm_fill_user_ctx(lx, size, value, error,
810 LSM_ID_APPARMOR, 0);
811 kfree(value);
812 }
813
814 aa_put_label(label);
815
816 if (error < 0)
817 return error;
818 return 1;
819}
820
821static int apparmor_getprocattr(struct task_struct *task, const char *name,
822 char **value)
823{
824 int error = -ENOENT;
825 /* released below */
826 const struct cred *cred = get_task_cred(task);
827 struct aa_task_ctx *ctx = task_ctx(current);
828 struct aa_label *label = NULL;
829
830 if (strcmp(name, "current") == 0)
831 label = aa_get_newest_label(cred_label(cred));
832 else if (strcmp(name, "prev") == 0 && ctx->previous)
833 label = aa_get_newest_label(ctx->previous);
834 else if (strcmp(name, "exec") == 0 && ctx->onexec)
835 label = aa_get_newest_label(ctx->onexec);
836 else
837 error = -EINVAL;
838
839 if (label)
840 error = aa_getprocattr(label, value, true);
841
842 aa_put_label(label);
843 put_cred(cred);
844
845 return error;
846}
847
848static int do_setattr(u64 attr, void *value, size_t size)
849{
850 char *command, *largs = NULL, *args = value;
851 size_t arg_size;
852 int error;
853 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_NONE,
854 OP_SETPROCATTR);
855
856 if (size == 0)
857 return -EINVAL;
858
859 /* AppArmor requires that the buffer must be null terminated atm */
860 if (args[size - 1] != '\0') {
861 /* null terminate */
862 largs = args = kmalloc(size + 1, GFP_KERNEL);
863 if (!args)
864 return -ENOMEM;
865 memcpy(args, value, size);
866 args[size] = '\0';
867 }
868
869 error = -EINVAL;
870 args = strim(args);
871 command = strsep(&args, " ");
872 if (!args)
873 goto out;
874 args = skip_spaces(args);
875 if (!*args)
876 goto out;
877
878 arg_size = size - (args - (largs ? largs : (char *) value));
879 if (attr == LSM_ATTR_CURRENT) {
880 if (strcmp(command, "changehat") == 0) {
881 error = aa_setprocattr_changehat(args, arg_size,
882 AA_CHANGE_NOFLAGS);
883 } else if (strcmp(command, "permhat") == 0) {
884 error = aa_setprocattr_changehat(args, arg_size,
885 AA_CHANGE_TEST);
886 } else if (strcmp(command, "changeprofile") == 0) {
887 error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
888 } else if (strcmp(command, "permprofile") == 0) {
889 error = aa_change_profile(args, AA_CHANGE_TEST);
890 } else if (strcmp(command, "stack") == 0) {
891 error = aa_change_profile(args, AA_CHANGE_STACK);
892 } else
893 goto fail;
894 } else if (attr == LSM_ATTR_EXEC) {
895 if (strcmp(command, "exec") == 0)
896 error = aa_change_profile(args, AA_CHANGE_ONEXEC);
897 else if (strcmp(command, "stack") == 0)
898 error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
899 AA_CHANGE_STACK));
900 else
901 goto fail;
902 } else
903 /* only support the "current" and "exec" process attributes */
904 goto fail;
905
906 if (!error)
907 error = size;
908out:
909 kfree(largs);
910 return error;
911
912fail:
913 ad.subj_label = begin_current_label_crit_section();
914 if (attr == LSM_ATTR_CURRENT)
915 ad.info = "current";
916 else if (attr == LSM_ATTR_EXEC)
917 ad.info = "exec";
918 else
919 ad.info = "invalid";
920 ad.error = error = -EINVAL;
921 aa_audit_msg(AUDIT_APPARMOR_DENIED, &ad, NULL);
922 end_current_label_crit_section(ad.subj_label);
923 goto out;
924}
925
926static int apparmor_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
927 size_t size, u32 flags)
928{
929 int rc;
930
931 if (attr != LSM_ATTR_CURRENT && attr != LSM_ATTR_EXEC)
932 return -EOPNOTSUPP;
933
934 rc = do_setattr(attr, ctx->ctx, ctx->ctx_len);
935 if (rc > 0)
936 return 0;
937 return rc;
938}
939
940static int apparmor_setprocattr(const char *name, void *value,
941 size_t size)
942{
943 int attr = lsm_name_to_attr(name);
944
945 if (attr)
946 return do_setattr(attr, value, size);
947 return -EINVAL;
948}
949
950/**
951 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
952 * @bprm: binprm for the exec (NOT NULL)
953 */
954static void apparmor_bprm_committing_creds(const struct linux_binprm *bprm)
955{
956 struct aa_label *label = aa_current_raw_label();
957 struct aa_label *new_label = cred_label(bprm->cred);
958
959 /* bail out if unconfined or not changing profile */
960 if ((new_label->proxy == label->proxy) ||
961 (unconfined(new_label)))
962 return;
963
964 aa_inherit_files(bprm->cred, current->files);
965
966 current->pdeath_signal = 0;
967
968 /* reset soft limits and set hard limits for the new label */
969 __aa_transition_rlimits(label, new_label);
970}
971
972/**
973 * apparmor_bprm_committed_creds() - do cleanup after new creds committed
974 * @bprm: binprm for the exec (NOT NULL)
975 */
976static void apparmor_bprm_committed_creds(const struct linux_binprm *bprm)
977{
978 /* clear out temporary/transitional state from the context */
979 aa_clear_task_ctx_trans(task_ctx(current));
980
981 return;
982}
983
984static void apparmor_current_getsecid_subj(u32 *secid)
985{
986 struct aa_label *label = __begin_current_label_crit_section();
987 *secid = label->secid;
988 __end_current_label_crit_section(label);
989}
990
991static void apparmor_task_getsecid_obj(struct task_struct *p, u32 *secid)
992{
993 struct aa_label *label = aa_get_task_label(p);
994 *secid = label->secid;
995 aa_put_label(label);
996}
997
998static int apparmor_task_setrlimit(struct task_struct *task,
999 unsigned int resource, struct rlimit *new_rlim)
1000{
1001 struct aa_label *label = __begin_current_label_crit_section();
1002 int error = 0;
1003
1004 if (!unconfined(label))
1005 error = aa_task_setrlimit(current_cred(), label, task,
1006 resource, new_rlim);
1007 __end_current_label_crit_section(label);
1008
1009 return error;
1010}
1011
1012static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo *info,
1013 int sig, const struct cred *cred)
1014{
1015 const struct cred *tc;
1016 struct aa_label *cl, *tl;
1017 int error;
1018
1019 tc = get_task_cred(target);
1020 tl = aa_get_newest_cred_label(tc);
1021 if (cred) {
1022 /*
1023 * Dealing with USB IO specific behavior
1024 */
1025 cl = aa_get_newest_cred_label(cred);
1026 error = aa_may_signal(cred, cl, tc, tl, sig);
1027 aa_put_label(cl);
1028 } else {
1029 cl = __begin_current_label_crit_section();
1030 error = aa_may_signal(current_cred(), cl, tc, tl, sig);
1031 __end_current_label_crit_section(cl);
1032 }
1033 aa_put_label(tl);
1034 put_cred(tc);
1035
1036 return error;
1037}
1038
1039static int apparmor_userns_create(const struct cred *cred)
1040{
1041 struct aa_label *label;
1042 struct aa_profile *profile;
1043 int error = 0;
1044 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_TASK, AA_CLASS_NS,
1045 OP_USERNS_CREATE);
1046
1047 ad.subj_cred = current_cred();
1048
1049 label = begin_current_label_crit_section();
1050 if (!unconfined(label)) {
1051 error = fn_for_each(label, profile,
1052 aa_profile_ns_perm(profile, &ad,
1053 AA_USERNS_CREATE));
1054 }
1055 end_current_label_crit_section(label);
1056
1057 return error;
1058}
1059
1060static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
1061{
1062 struct aa_sk_ctx *ctx;
1063
1064 ctx = kzalloc(sizeof(*ctx), flags);
1065 if (!ctx)
1066 return -ENOMEM;
1067
1068 sk->sk_security = ctx;
1069
1070 return 0;
1071}
1072
1073static void apparmor_sk_free_security(struct sock *sk)
1074{
1075 struct aa_sk_ctx *ctx = aa_sock(sk);
1076
1077 sk->sk_security = NULL;
1078 aa_put_label(ctx->label);
1079 aa_put_label(ctx->peer);
1080 kfree(ctx);
1081}
1082
1083/**
1084 * apparmor_sk_clone_security - clone the sk_security field
1085 * @sk: sock to have security cloned
1086 * @newsk: sock getting clone
1087 */
1088static void apparmor_sk_clone_security(const struct sock *sk,
1089 struct sock *newsk)
1090{
1091 struct aa_sk_ctx *ctx = aa_sock(sk);
1092 struct aa_sk_ctx *new = aa_sock(newsk);
1093
1094 if (new->label)
1095 aa_put_label(new->label);
1096 new->label = aa_get_label(ctx->label);
1097
1098 if (new->peer)
1099 aa_put_label(new->peer);
1100 new->peer = aa_get_label(ctx->peer);
1101}
1102
1103static int apparmor_socket_create(int family, int type, int protocol, int kern)
1104{
1105 struct aa_label *label;
1106 int error = 0;
1107
1108 AA_BUG(in_interrupt());
1109
1110 label = begin_current_label_crit_section();
1111 if (!(kern || unconfined(label)))
1112 error = af_select(family,
1113 create_perm(label, family, type, protocol),
1114 aa_af_perm(current_cred(), label,
1115 OP_CREATE, AA_MAY_CREATE,
1116 family, type, protocol));
1117 end_current_label_crit_section(label);
1118
1119 return error;
1120}
1121
1122/**
1123 * apparmor_socket_post_create - setup the per-socket security struct
1124 * @sock: socket that is being setup
1125 * @family: family of socket being created
1126 * @type: type of the socket
1127 * @ptotocol: protocol of the socket
1128 * @kern: socket is a special kernel socket
1129 *
1130 * Note:
1131 * - kernel sockets labeled kernel_t used to use unconfined
1132 * - socket may not have sk here if created with sock_create_lite or
1133 * sock_alloc. These should be accept cases which will be handled in
1134 * sock_graft.
1135 */
1136static int apparmor_socket_post_create(struct socket *sock, int family,
1137 int type, int protocol, int kern)
1138{
1139 struct aa_label *label;
1140
1141 if (kern) {
1142 label = aa_get_label(kernel_t);
1143 } else
1144 label = aa_get_current_label();
1145
1146 if (sock->sk) {
1147 struct aa_sk_ctx *ctx = aa_sock(sock->sk);
1148
1149 aa_put_label(ctx->label);
1150 ctx->label = aa_get_label(label);
1151 }
1152 aa_put_label(label);
1153
1154 return 0;
1155}
1156
1157static int apparmor_socket_bind(struct socket *sock,
1158 struct sockaddr *address, int addrlen)
1159{
1160 AA_BUG(!sock);
1161 AA_BUG(!sock->sk);
1162 AA_BUG(!address);
1163 AA_BUG(in_interrupt());
1164
1165 return af_select(sock->sk->sk_family,
1166 bind_perm(sock, address, addrlen),
1167 aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk));
1168}
1169
1170static int apparmor_socket_connect(struct socket *sock,
1171 struct sockaddr *address, int addrlen)
1172{
1173 AA_BUG(!sock);
1174 AA_BUG(!sock->sk);
1175 AA_BUG(!address);
1176 AA_BUG(in_interrupt());
1177
1178 return af_select(sock->sk->sk_family,
1179 connect_perm(sock, address, addrlen),
1180 aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk));
1181}
1182
1183static int apparmor_socket_listen(struct socket *sock, int backlog)
1184{
1185 AA_BUG(!sock);
1186 AA_BUG(!sock->sk);
1187 AA_BUG(in_interrupt());
1188
1189 return af_select(sock->sk->sk_family,
1190 listen_perm(sock, backlog),
1191 aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk));
1192}
1193
1194/*
1195 * Note: while @newsock is created and has some information, the accept
1196 * has not been done.
1197 */
1198static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
1199{
1200 AA_BUG(!sock);
1201 AA_BUG(!sock->sk);
1202 AA_BUG(!newsock);
1203 AA_BUG(in_interrupt());
1204
1205 return af_select(sock->sk->sk_family,
1206 accept_perm(sock, newsock),
1207 aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk));
1208}
1209
1210static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
1211 struct msghdr *msg, int size)
1212{
1213 AA_BUG(!sock);
1214 AA_BUG(!sock->sk);
1215 AA_BUG(!msg);
1216 AA_BUG(in_interrupt());
1217
1218 return af_select(sock->sk->sk_family,
1219 msg_perm(op, request, sock, msg, size),
1220 aa_sk_perm(op, request, sock->sk));
1221}
1222
1223static int apparmor_socket_sendmsg(struct socket *sock,
1224 struct msghdr *msg, int size)
1225{
1226 return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
1227}
1228
1229static int apparmor_socket_recvmsg(struct socket *sock,
1230 struct msghdr *msg, int size, int flags)
1231{
1232 return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
1233}
1234
1235/* revaliation, get/set attr, shutdown */
1236static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
1237{
1238 AA_BUG(!sock);
1239 AA_BUG(!sock->sk);
1240 AA_BUG(in_interrupt());
1241
1242 return af_select(sock->sk->sk_family,
1243 sock_perm(op, request, sock),
1244 aa_sk_perm(op, request, sock->sk));
1245}
1246
1247static int apparmor_socket_getsockname(struct socket *sock)
1248{
1249 return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
1250}
1251
1252static int apparmor_socket_getpeername(struct socket *sock)
1253{
1254 return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
1255}
1256
1257/* revaliation, get/set attr, opt */
1258static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
1259 int level, int optname)
1260{
1261 AA_BUG(!sock);
1262 AA_BUG(!sock->sk);
1263 AA_BUG(in_interrupt());
1264
1265 return af_select(sock->sk->sk_family,
1266 opt_perm(op, request, sock, level, optname),
1267 aa_sk_perm(op, request, sock->sk));
1268}
1269
1270static int apparmor_socket_getsockopt(struct socket *sock, int level,
1271 int optname)
1272{
1273 return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
1274 level, optname);
1275}
1276
1277static int apparmor_socket_setsockopt(struct socket *sock, int level,
1278 int optname)
1279{
1280 return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
1281 level, optname);
1282}
1283
1284static int apparmor_socket_shutdown(struct socket *sock, int how)
1285{
1286 return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
1287}
1288
1289#ifdef CONFIG_NETWORK_SECMARK
1290/**
1291 * apparmor_socket_sock_rcv_skb - check perms before associating skb to sk
1292 * @sk: sk to associate @skb with
1293 * @skb: skb to check for perms
1294 *
1295 * Note: can not sleep may be called with locks held
1296 *
1297 * dont want protocol specific in __skb_recv_datagram()
1298 * to deny an incoming connection socket_sock_rcv_skb()
1299 */
1300static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
1301{
1302 struct aa_sk_ctx *ctx = aa_sock(sk);
1303
1304 if (!skb->secmark)
1305 return 0;
1306
1307 return apparmor_secmark_check(ctx->label, OP_RECVMSG, AA_MAY_RECEIVE,
1308 skb->secmark, sk);
1309}
1310#endif
1311
1312
1313static struct aa_label *sk_peer_label(struct sock *sk)
1314{
1315 struct aa_sk_ctx *ctx = aa_sock(sk);
1316
1317 if (ctx->peer)
1318 return ctx->peer;
1319
1320 return ERR_PTR(-ENOPROTOOPT);
1321}
1322
1323/**
1324 * apparmor_socket_getpeersec_stream - get security context of peer
1325 * @sock: socket that we are trying to get the peer context of
1326 * @optval: output - buffer to copy peer name to
1327 * @optlen: output - size of copied name in @optval
1328 * @len: size of @optval buffer
1329 * Returns: 0 on success, -errno of failure
1330 *
1331 * Note: for tcp only valid if using ipsec or cipso on lan
1332 */
1333static int apparmor_socket_getpeersec_stream(struct socket *sock,
1334 sockptr_t optval, sockptr_t optlen,
1335 unsigned int len)
1336{
1337 char *name = NULL;
1338 int slen, error = 0;
1339 struct aa_label *label;
1340 struct aa_label *peer;
1341
1342 label = begin_current_label_crit_section();
1343 peer = sk_peer_label(sock->sk);
1344 if (IS_ERR(peer)) {
1345 error = PTR_ERR(peer);
1346 goto done;
1347 }
1348 slen = aa_label_asxprint(&name, labels_ns(label), peer,
1349 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
1350 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
1351 /* don't include terminating \0 in slen, it breaks some apps */
1352 if (slen < 0) {
1353 error = -ENOMEM;
1354 goto done;
1355 }
1356 if (slen > len) {
1357 error = -ERANGE;
1358 goto done_len;
1359 }
1360
1361 if (copy_to_sockptr(optval, name, slen))
1362 error = -EFAULT;
1363done_len:
1364 if (copy_to_sockptr(optlen, &slen, sizeof(slen)))
1365 error = -EFAULT;
1366done:
1367 end_current_label_crit_section(label);
1368 kfree(name);
1369 return error;
1370}
1371
1372/**
1373 * apparmor_socket_getpeersec_dgram - get security label of packet
1374 * @sock: the peer socket
1375 * @skb: packet data
1376 * @secid: pointer to where to put the secid of the packet
1377 *
1378 * Sets the netlabel socket state on sk from parent
1379 */
1380static int apparmor_socket_getpeersec_dgram(struct socket *sock,
1381 struct sk_buff *skb, u32 *secid)
1382
1383{
1384 /* TODO: requires secid support */
1385 return -ENOPROTOOPT;
1386}
1387
1388/**
1389 * apparmor_sock_graft - Initialize newly created socket
1390 * @sk: child sock
1391 * @parent: parent socket
1392 *
1393 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
1394 * just set sk security information off of current creating process label
1395 * Labeling of sk for accept case - probably should be sock based
1396 * instead of task, because of the case where an implicitly labeled
1397 * socket is shared by different tasks.
1398 */
1399static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
1400{
1401 struct aa_sk_ctx *ctx = aa_sock(sk);
1402
1403 if (!ctx->label)
1404 ctx->label = aa_get_current_label();
1405}
1406
1407#ifdef CONFIG_NETWORK_SECMARK
1408static int apparmor_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
1409 struct request_sock *req)
1410{
1411 struct aa_sk_ctx *ctx = aa_sock(sk);
1412
1413 if (!skb->secmark)
1414 return 0;
1415
1416 return apparmor_secmark_check(ctx->label, OP_CONNECT, AA_MAY_CONNECT,
1417 skb->secmark, sk);
1418}
1419#endif
1420
1421/*
1422 * The cred blob is a pointer to, not an instance of, an aa_label.
1423 */
1424struct lsm_blob_sizes apparmor_blob_sizes __ro_after_init = {
1425 .lbs_cred = sizeof(struct aa_label *),
1426 .lbs_file = sizeof(struct aa_file_ctx),
1427 .lbs_task = sizeof(struct aa_task_ctx),
1428};
1429
1430static const struct lsm_id apparmor_lsmid = {
1431 .name = "apparmor",
1432 .id = LSM_ID_APPARMOR,
1433};
1434
1435static struct security_hook_list apparmor_hooks[] __ro_after_init = {
1436 LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
1437 LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
1438 LSM_HOOK_INIT(capget, apparmor_capget),
1439 LSM_HOOK_INIT(capable, apparmor_capable),
1440
1441 LSM_HOOK_INIT(move_mount, apparmor_move_mount),
1442 LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
1443 LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
1444 LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
1445
1446 LSM_HOOK_INIT(path_link, apparmor_path_link),
1447 LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
1448 LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
1449 LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
1450 LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
1451 LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
1452 LSM_HOOK_INIT(path_rename, apparmor_path_rename),
1453 LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
1454 LSM_HOOK_INIT(path_chown, apparmor_path_chown),
1455 LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
1456 LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
1457
1458 LSM_HOOK_INIT(file_open, apparmor_file_open),
1459 LSM_HOOK_INIT(file_receive, apparmor_file_receive),
1460 LSM_HOOK_INIT(file_permission, apparmor_file_permission),
1461 LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
1462 LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
1463 LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
1464 LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
1465 LSM_HOOK_INIT(file_lock, apparmor_file_lock),
1466 LSM_HOOK_INIT(file_truncate, apparmor_file_truncate),
1467
1468 LSM_HOOK_INIT(getselfattr, apparmor_getselfattr),
1469 LSM_HOOK_INIT(setselfattr, apparmor_setselfattr),
1470 LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
1471 LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
1472
1473 LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
1474 LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
1475 LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
1476
1477 LSM_HOOK_INIT(socket_create, apparmor_socket_create),
1478 LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
1479 LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
1480 LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
1481 LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
1482 LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
1483 LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
1484 LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
1485 LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
1486 LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
1487 LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
1488 LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
1489 LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
1490#ifdef CONFIG_NETWORK_SECMARK
1491 LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
1492#endif
1493 LSM_HOOK_INIT(socket_getpeersec_stream,
1494 apparmor_socket_getpeersec_stream),
1495 LSM_HOOK_INIT(socket_getpeersec_dgram,
1496 apparmor_socket_getpeersec_dgram),
1497 LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
1498#ifdef CONFIG_NETWORK_SECMARK
1499 LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request),
1500#endif
1501
1502 LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
1503 LSM_HOOK_INIT(cred_free, apparmor_cred_free),
1504 LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
1505 LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
1506
1507 LSM_HOOK_INIT(bprm_creds_for_exec, apparmor_bprm_creds_for_exec),
1508 LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
1509 LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
1510
1511 LSM_HOOK_INIT(task_free, apparmor_task_free),
1512 LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
1513 LSM_HOOK_INIT(current_getsecid_subj, apparmor_current_getsecid_subj),
1514 LSM_HOOK_INIT(task_getsecid_obj, apparmor_task_getsecid_obj),
1515 LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
1516 LSM_HOOK_INIT(task_kill, apparmor_task_kill),
1517 LSM_HOOK_INIT(userns_create, apparmor_userns_create),
1518
1519#ifdef CONFIG_AUDIT
1520 LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init),
1521 LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known),
1522 LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match),
1523 LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free),
1524#endif
1525
1526 LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
1527 LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
1528 LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
1529
1530#ifdef CONFIG_IO_URING
1531 LSM_HOOK_INIT(uring_override_creds, apparmor_uring_override_creds),
1532 LSM_HOOK_INIT(uring_sqpoll, apparmor_uring_sqpoll),
1533#endif
1534};
1535
1536/*
1537 * AppArmor sysfs module parameters
1538 */
1539
1540static int param_set_aabool(const char *val, const struct kernel_param *kp);
1541static int param_get_aabool(char *buffer, const struct kernel_param *kp);
1542#define param_check_aabool param_check_bool
1543static const struct kernel_param_ops param_ops_aabool = {
1544 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1545 .set = param_set_aabool,
1546 .get = param_get_aabool
1547};
1548
1549static int param_set_aauint(const char *val, const struct kernel_param *kp);
1550static int param_get_aauint(char *buffer, const struct kernel_param *kp);
1551#define param_check_aauint param_check_uint
1552static const struct kernel_param_ops param_ops_aauint = {
1553 .set = param_set_aauint,
1554 .get = param_get_aauint
1555};
1556
1557static int param_set_aacompressionlevel(const char *val,
1558 const struct kernel_param *kp);
1559static int param_get_aacompressionlevel(char *buffer,
1560 const struct kernel_param *kp);
1561#define param_check_aacompressionlevel param_check_int
1562static const struct kernel_param_ops param_ops_aacompressionlevel = {
1563 .set = param_set_aacompressionlevel,
1564 .get = param_get_aacompressionlevel
1565};
1566
1567static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
1568static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
1569#define param_check_aalockpolicy param_check_bool
1570static const struct kernel_param_ops param_ops_aalockpolicy = {
1571 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1572 .set = param_set_aalockpolicy,
1573 .get = param_get_aalockpolicy
1574};
1575
1576static int param_set_audit(const char *val, const struct kernel_param *kp);
1577static int param_get_audit(char *buffer, const struct kernel_param *kp);
1578
1579static int param_set_mode(const char *val, const struct kernel_param *kp);
1580static int param_get_mode(char *buffer, const struct kernel_param *kp);
1581
1582/* Flag values, also controllable via /sys/module/apparmor/parameters
1583 * We define special types as we want to do additional mediation.
1584 */
1585
1586/* AppArmor global enforcement switch - complain, enforce, kill */
1587enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
1588module_param_call(mode, param_set_mode, param_get_mode,
1589 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
1590
1591/* whether policy verification hashing is enabled */
1592bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
1593#ifdef CONFIG_SECURITY_APPARMOR_HASH
1594module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
1595#endif
1596
1597/* whether policy exactly as loaded is retained for debug and checkpointing */
1598bool aa_g_export_binary = IS_ENABLED(CONFIG_SECURITY_APPARMOR_EXPORT_BINARY);
1599#ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY
1600module_param_named(export_binary, aa_g_export_binary, aabool, 0600);
1601#endif
1602
1603/* policy loaddata compression level */
1604int aa_g_rawdata_compression_level = AA_DEFAULT_CLEVEL;
1605module_param_named(rawdata_compression_level, aa_g_rawdata_compression_level,
1606 aacompressionlevel, 0400);
1607
1608/* Debug mode */
1609bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
1610module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
1611
1612/* Audit mode */
1613enum audit_mode aa_g_audit;
1614module_param_call(audit, param_set_audit, param_get_audit,
1615 &aa_g_audit, S_IRUSR | S_IWUSR);
1616
1617/* Determines if audit header is included in audited messages. This
1618 * provides more context if the audit daemon is not running
1619 */
1620bool aa_g_audit_header = true;
1621module_param_named(audit_header, aa_g_audit_header, aabool,
1622 S_IRUSR | S_IWUSR);
1623
1624/* lock out loading/removal of policy
1625 * TODO: add in at boot loading of policy, which is the only way to
1626 * load policy, if lock_policy is set
1627 */
1628bool aa_g_lock_policy;
1629module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
1630 S_IRUSR | S_IWUSR);
1631
1632/* Syscall logging mode */
1633bool aa_g_logsyscall;
1634module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
1635
1636/* Maximum pathname length before accesses will start getting rejected */
1637unsigned int aa_g_path_max = 2 * PATH_MAX;
1638module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
1639
1640/* Determines how paranoid loading of policy is and how much verification
1641 * on the loaded policy is done.
1642 * DEPRECATED: read only as strict checking of load is always done now
1643 * that none root users (user namespaces) can load policy.
1644 */
1645bool aa_g_paranoid_load = IS_ENABLED(CONFIG_SECURITY_APPARMOR_PARANOID_LOAD);
1646module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
1647
1648static int param_get_aaintbool(char *buffer, const struct kernel_param *kp);
1649static int param_set_aaintbool(const char *val, const struct kernel_param *kp);
1650#define param_check_aaintbool param_check_int
1651static const struct kernel_param_ops param_ops_aaintbool = {
1652 .set = param_set_aaintbool,
1653 .get = param_get_aaintbool
1654};
1655/* Boot time disable flag */
1656static int apparmor_enabled __ro_after_init = 1;
1657module_param_named(enabled, apparmor_enabled, aaintbool, 0444);
1658
1659static int __init apparmor_enabled_setup(char *str)
1660{
1661 unsigned long enabled;
1662 int error = kstrtoul(str, 0, &enabled);
1663 if (!error)
1664 apparmor_enabled = enabled ? 1 : 0;
1665 return 1;
1666}
1667
1668__setup("apparmor=", apparmor_enabled_setup);
1669
1670/* set global flag turning off the ability to load policy */
1671static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
1672{
1673 if (!apparmor_enabled)
1674 return -EINVAL;
1675 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
1676 return -EPERM;
1677 return param_set_bool(val, kp);
1678}
1679
1680static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
1681{
1682 if (!apparmor_enabled)
1683 return -EINVAL;
1684 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1685 return -EPERM;
1686 return param_get_bool(buffer, kp);
1687}
1688
1689static int param_set_aabool(const char *val, const struct kernel_param *kp)
1690{
1691 if (!apparmor_enabled)
1692 return -EINVAL;
1693 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
1694 return -EPERM;
1695 return param_set_bool(val, kp);
1696}
1697
1698static int param_get_aabool(char *buffer, const struct kernel_param *kp)
1699{
1700 if (!apparmor_enabled)
1701 return -EINVAL;
1702 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1703 return -EPERM;
1704 return param_get_bool(buffer, kp);
1705}
1706
1707static int param_set_aauint(const char *val, const struct kernel_param *kp)
1708{
1709 int error;
1710
1711 if (!apparmor_enabled)
1712 return -EINVAL;
1713 /* file is ro but enforce 2nd line check */
1714 if (apparmor_initialized)
1715 return -EPERM;
1716
1717 error = param_set_uint(val, kp);
1718 aa_g_path_max = max_t(uint32_t, aa_g_path_max, sizeof(union aa_buffer));
1719 pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
1720
1721 return error;
1722}
1723
1724static int param_get_aauint(char *buffer, const struct kernel_param *kp)
1725{
1726 if (!apparmor_enabled)
1727 return -EINVAL;
1728 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1729 return -EPERM;
1730 return param_get_uint(buffer, kp);
1731}
1732
1733/* Can only be set before AppArmor is initialized (i.e. on boot cmdline). */
1734static int param_set_aaintbool(const char *val, const struct kernel_param *kp)
1735{
1736 struct kernel_param kp_local;
1737 bool value;
1738 int error;
1739
1740 if (apparmor_initialized)
1741 return -EPERM;
1742
1743 /* Create local copy, with arg pointing to bool type. */
1744 value = !!*((int *)kp->arg);
1745 memcpy(&kp_local, kp, sizeof(kp_local));
1746 kp_local.arg = &value;
1747
1748 error = param_set_bool(val, &kp_local);
1749 if (!error)
1750 *((int *)kp->arg) = *((bool *)kp_local.arg);
1751 return error;
1752}
1753
1754/*
1755 * To avoid changing /sys/module/apparmor/parameters/enabled from Y/N to
1756 * 1/0, this converts the "int that is actually bool" back to bool for
1757 * display in the /sys filesystem, while keeping it "int" for the LSM
1758 * infrastructure.
1759 */
1760static int param_get_aaintbool(char *buffer, const struct kernel_param *kp)
1761{
1762 struct kernel_param kp_local;
1763 bool value;
1764
1765 /* Create local copy, with arg pointing to bool type. */
1766 value = !!*((int *)kp->arg);
1767 memcpy(&kp_local, kp, sizeof(kp_local));
1768 kp_local.arg = &value;
1769
1770 return param_get_bool(buffer, &kp_local);
1771}
1772
1773static int param_set_aacompressionlevel(const char *val,
1774 const struct kernel_param *kp)
1775{
1776 int error;
1777
1778 if (!apparmor_enabled)
1779 return -EINVAL;
1780 if (apparmor_initialized)
1781 return -EPERM;
1782
1783 error = param_set_int(val, kp);
1784
1785 aa_g_rawdata_compression_level = clamp(aa_g_rawdata_compression_level,
1786 AA_MIN_CLEVEL, AA_MAX_CLEVEL);
1787 pr_info("AppArmor: policy rawdata compression level set to %d\n",
1788 aa_g_rawdata_compression_level);
1789
1790 return error;
1791}
1792
1793static int param_get_aacompressionlevel(char *buffer,
1794 const struct kernel_param *kp)
1795{
1796 if (!apparmor_enabled)
1797 return -EINVAL;
1798 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1799 return -EPERM;
1800 return param_get_int(buffer, kp);
1801}
1802
1803static int param_get_audit(char *buffer, const struct kernel_param *kp)
1804{
1805 if (!apparmor_enabled)
1806 return -EINVAL;
1807 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1808 return -EPERM;
1809 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
1810}
1811
1812static int param_set_audit(const char *val, const struct kernel_param *kp)
1813{
1814 int i;
1815
1816 if (!apparmor_enabled)
1817 return -EINVAL;
1818 if (!val)
1819 return -EINVAL;
1820 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
1821 return -EPERM;
1822
1823 i = match_string(audit_mode_names, AUDIT_MAX_INDEX, val);
1824 if (i < 0)
1825 return -EINVAL;
1826
1827 aa_g_audit = i;
1828 return 0;
1829}
1830
1831static int param_get_mode(char *buffer, const struct kernel_param *kp)
1832{
1833 if (!apparmor_enabled)
1834 return -EINVAL;
1835 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1836 return -EPERM;
1837
1838 return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
1839}
1840
1841static int param_set_mode(const char *val, const struct kernel_param *kp)
1842{
1843 int i;
1844
1845 if (!apparmor_enabled)
1846 return -EINVAL;
1847 if (!val)
1848 return -EINVAL;
1849 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
1850 return -EPERM;
1851
1852 i = match_string(aa_profile_mode_names, APPARMOR_MODE_NAMES_MAX_INDEX,
1853 val);
1854 if (i < 0)
1855 return -EINVAL;
1856
1857 aa_g_profile_mode = i;
1858 return 0;
1859}
1860
1861char *aa_get_buffer(bool in_atomic)
1862{
1863 union aa_buffer *aa_buf;
1864 struct aa_local_cache *cache;
1865 bool try_again = true;
1866 gfp_t flags = (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
1867
1868 /* use per cpu cached buffers first */
1869 cache = get_cpu_ptr(&aa_local_buffers);
1870 if (!list_empty(&cache->head)) {
1871 aa_buf = list_first_entry(&cache->head, union aa_buffer, list);
1872 list_del(&aa_buf->list);
1873 cache->hold--;
1874 cache->count--;
1875 put_cpu_ptr(&aa_local_buffers);
1876 return &aa_buf->buffer[0];
1877 }
1878 put_cpu_ptr(&aa_local_buffers);
1879
1880 if (!spin_trylock(&aa_buffers_lock)) {
1881 cache = get_cpu_ptr(&aa_local_buffers);
1882 cache->hold += 1;
1883 put_cpu_ptr(&aa_local_buffers);
1884 spin_lock(&aa_buffers_lock);
1885 } else {
1886 cache = get_cpu_ptr(&aa_local_buffers);
1887 put_cpu_ptr(&aa_local_buffers);
1888 }
1889retry:
1890 if (buffer_count > reserve_count ||
1891 (in_atomic && !list_empty(&aa_global_buffers))) {
1892 aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
1893 list);
1894 list_del(&aa_buf->list);
1895 buffer_count--;
1896 spin_unlock(&aa_buffers_lock);
1897 return aa_buf->buffer;
1898 }
1899 if (in_atomic) {
1900 /*
1901 * out of reserve buffers and in atomic context so increase
1902 * how many buffers to keep in reserve
1903 */
1904 reserve_count++;
1905 flags = GFP_ATOMIC;
1906 }
1907 spin_unlock(&aa_buffers_lock);
1908
1909 if (!in_atomic)
1910 might_sleep();
1911 aa_buf = kmalloc(aa_g_path_max, flags);
1912 if (!aa_buf) {
1913 if (try_again) {
1914 try_again = false;
1915 spin_lock(&aa_buffers_lock);
1916 goto retry;
1917 }
1918 pr_warn_once("AppArmor: Failed to allocate a memory buffer.\n");
1919 return NULL;
1920 }
1921 return aa_buf->buffer;
1922}
1923
1924void aa_put_buffer(char *buf)
1925{
1926 union aa_buffer *aa_buf;
1927 struct aa_local_cache *cache;
1928
1929 if (!buf)
1930 return;
1931 aa_buf = container_of(buf, union aa_buffer, buffer[0]);
1932
1933 cache = get_cpu_ptr(&aa_local_buffers);
1934 if (!cache->hold) {
1935 put_cpu_ptr(&aa_local_buffers);
1936
1937 if (spin_trylock(&aa_buffers_lock)) {
1938 /* put back on global list */
1939 list_add(&aa_buf->list, &aa_global_buffers);
1940 buffer_count++;
1941 spin_unlock(&aa_buffers_lock);
1942 cache = get_cpu_ptr(&aa_local_buffers);
1943 put_cpu_ptr(&aa_local_buffers);
1944 return;
1945 }
1946 /* contention on global list, fallback to percpu */
1947 cache = get_cpu_ptr(&aa_local_buffers);
1948 cache->hold += 1;
1949 }
1950
1951 /* cache in percpu list */
1952 list_add(&aa_buf->list, &cache->head);
1953 cache->count++;
1954 put_cpu_ptr(&aa_local_buffers);
1955}
1956
1957/*
1958 * AppArmor init functions
1959 */
1960
1961/**
1962 * set_init_ctx - set a task context and profile on the first task.
1963 *
1964 * TODO: allow setting an alternate profile than unconfined
1965 */
1966static int __init set_init_ctx(void)
1967{
1968 struct cred *cred = (__force struct cred *)current->real_cred;
1969
1970 set_cred_label(cred, aa_get_label(ns_unconfined(root_ns)));
1971
1972 return 0;
1973}
1974
1975static void destroy_buffers(void)
1976{
1977 union aa_buffer *aa_buf;
1978
1979 spin_lock(&aa_buffers_lock);
1980 while (!list_empty(&aa_global_buffers)) {
1981 aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
1982 list);
1983 list_del(&aa_buf->list);
1984 spin_unlock(&aa_buffers_lock);
1985 kfree(aa_buf);
1986 spin_lock(&aa_buffers_lock);
1987 }
1988 spin_unlock(&aa_buffers_lock);
1989}
1990
1991static int __init alloc_buffers(void)
1992{
1993 union aa_buffer *aa_buf;
1994 int i, num;
1995
1996 /*
1997 * per cpu set of cached allocated buffers used to help reduce
1998 * lock contention
1999 */
2000 for_each_possible_cpu(i) {
2001 per_cpu(aa_local_buffers, i).hold = 0;
2002 per_cpu(aa_local_buffers, i).count = 0;
2003 INIT_LIST_HEAD(&per_cpu(aa_local_buffers, i).head);
2004 }
2005 /*
2006 * A function may require two buffers at once. Usually the buffers are
2007 * used for a short period of time and are shared. On UP kernel buffers
2008 * two should be enough, with more CPUs it is possible that more
2009 * buffers will be used simultaneously. The preallocated pool may grow.
2010 * This preallocation has also the side-effect that AppArmor will be
2011 * disabled early at boot if aa_g_path_max is extremly high.
2012 */
2013 if (num_online_cpus() > 1)
2014 num = 4 + RESERVE_COUNT;
2015 else
2016 num = 2 + RESERVE_COUNT;
2017
2018 for (i = 0; i < num; i++) {
2019
2020 aa_buf = kmalloc(aa_g_path_max, GFP_KERNEL |
2021 __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
2022 if (!aa_buf) {
2023 destroy_buffers();
2024 return -ENOMEM;
2025 }
2026 aa_put_buffer(aa_buf->buffer);
2027 }
2028 return 0;
2029}
2030
2031#ifdef CONFIG_SYSCTL
2032static int apparmor_dointvec(struct ctl_table *table, int write,
2033 void *buffer, size_t *lenp, loff_t *ppos)
2034{
2035 if (!aa_current_policy_admin_capable(NULL))
2036 return -EPERM;
2037 if (!apparmor_enabled)
2038 return -EINVAL;
2039
2040 return proc_dointvec(table, write, buffer, lenp, ppos);
2041}
2042
2043static struct ctl_table apparmor_sysctl_table[] = {
2044#ifdef CONFIG_USER_NS
2045 {
2046 .procname = "unprivileged_userns_apparmor_policy",
2047 .data = &unprivileged_userns_apparmor_policy,
2048 .maxlen = sizeof(int),
2049 .mode = 0600,
2050 .proc_handler = apparmor_dointvec,
2051 },
2052#endif /* CONFIG_USER_NS */
2053 {
2054 .procname = "apparmor_display_secid_mode",
2055 .data = &apparmor_display_secid_mode,
2056 .maxlen = sizeof(int),
2057 .mode = 0600,
2058 .proc_handler = apparmor_dointvec,
2059 },
2060 {
2061 .procname = "apparmor_restrict_unprivileged_unconfined",
2062 .data = &aa_unprivileged_unconfined_restricted,
2063 .maxlen = sizeof(int),
2064 .mode = 0600,
2065 .proc_handler = apparmor_dointvec,
2066 },
2067 { }
2068};
2069
2070static int __init apparmor_init_sysctl(void)
2071{
2072 return register_sysctl("kernel", apparmor_sysctl_table) ? 0 : -ENOMEM;
2073}
2074#else
2075static inline int apparmor_init_sysctl(void)
2076{
2077 return 0;
2078}
2079#endif /* CONFIG_SYSCTL */
2080
2081#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
2082static unsigned int apparmor_ip_postroute(void *priv,
2083 struct sk_buff *skb,
2084 const struct nf_hook_state *state)
2085{
2086 struct aa_sk_ctx *ctx;
2087 struct sock *sk;
2088
2089 if (!skb->secmark)
2090 return NF_ACCEPT;
2091
2092 sk = skb_to_full_sk(skb);
2093 if (sk == NULL)
2094 return NF_ACCEPT;
2095
2096 ctx = aa_sock(sk);
2097 if (!apparmor_secmark_check(ctx->label, OP_SENDMSG, AA_MAY_SEND,
2098 skb->secmark, sk))
2099 return NF_ACCEPT;
2100
2101 return NF_DROP_ERR(-ECONNREFUSED);
2102
2103}
2104
2105static const struct nf_hook_ops apparmor_nf_ops[] = {
2106 {
2107 .hook = apparmor_ip_postroute,
2108 .pf = NFPROTO_IPV4,
2109 .hooknum = NF_INET_POST_ROUTING,
2110 .priority = NF_IP_PRI_SELINUX_FIRST,
2111 },
2112#if IS_ENABLED(CONFIG_IPV6)
2113 {
2114 .hook = apparmor_ip_postroute,
2115 .pf = NFPROTO_IPV6,
2116 .hooknum = NF_INET_POST_ROUTING,
2117 .priority = NF_IP6_PRI_SELINUX_FIRST,
2118 },
2119#endif
2120};
2121
2122static int __net_init apparmor_nf_register(struct net *net)
2123{
2124 return nf_register_net_hooks(net, apparmor_nf_ops,
2125 ARRAY_SIZE(apparmor_nf_ops));
2126}
2127
2128static void __net_exit apparmor_nf_unregister(struct net *net)
2129{
2130 nf_unregister_net_hooks(net, apparmor_nf_ops,
2131 ARRAY_SIZE(apparmor_nf_ops));
2132}
2133
2134static struct pernet_operations apparmor_net_ops = {
2135 .init = apparmor_nf_register,
2136 .exit = apparmor_nf_unregister,
2137};
2138
2139static int __init apparmor_nf_ip_init(void)
2140{
2141 int err;
2142
2143 if (!apparmor_enabled)
2144 return 0;
2145
2146 err = register_pernet_subsys(&apparmor_net_ops);
2147 if (err)
2148 panic("Apparmor: register_pernet_subsys: error %d\n", err);
2149
2150 return 0;
2151}
2152__initcall(apparmor_nf_ip_init);
2153#endif
2154
2155static char nulldfa_src[] = {
2156 #include "nulldfa.in"
2157};
2158static struct aa_dfa *nulldfa;
2159
2160static char stacksplitdfa_src[] = {
2161 #include "stacksplitdfa.in"
2162};
2163struct aa_dfa *stacksplitdfa;
2164struct aa_policydb *nullpdb;
2165
2166static int __init aa_setup_dfa_engine(void)
2167{
2168 int error = -ENOMEM;
2169
2170 nullpdb = aa_alloc_pdb(GFP_KERNEL);
2171 if (!nullpdb)
2172 return -ENOMEM;
2173
2174 nulldfa = aa_dfa_unpack(nulldfa_src, sizeof(nulldfa_src),
2175 TO_ACCEPT1_FLAG(YYTD_DATA32) |
2176 TO_ACCEPT2_FLAG(YYTD_DATA32));
2177 if (IS_ERR(nulldfa)) {
2178 error = PTR_ERR(nulldfa);
2179 goto fail;
2180 }
2181 nullpdb->dfa = aa_get_dfa(nulldfa);
2182 nullpdb->perms = kcalloc(2, sizeof(struct aa_perms), GFP_KERNEL);
2183 if (!nullpdb->perms)
2184 goto fail;
2185 nullpdb->size = 2;
2186
2187 stacksplitdfa = aa_dfa_unpack(stacksplitdfa_src,
2188 sizeof(stacksplitdfa_src),
2189 TO_ACCEPT1_FLAG(YYTD_DATA32) |
2190 TO_ACCEPT2_FLAG(YYTD_DATA32));
2191 if (IS_ERR(stacksplitdfa)) {
2192 error = PTR_ERR(stacksplitdfa);
2193 goto fail;
2194 }
2195
2196 return 0;
2197
2198fail:
2199 aa_put_pdb(nullpdb);
2200 aa_put_dfa(nulldfa);
2201 nullpdb = NULL;
2202 nulldfa = NULL;
2203 stacksplitdfa = NULL;
2204
2205 return error;
2206}
2207
2208static void __init aa_teardown_dfa_engine(void)
2209{
2210 aa_put_dfa(stacksplitdfa);
2211 aa_put_dfa(nulldfa);
2212 aa_put_pdb(nullpdb);
2213 nullpdb = NULL;
2214 stacksplitdfa = NULL;
2215 nulldfa = NULL;
2216}
2217
2218static int __init apparmor_init(void)
2219{
2220 int error;
2221
2222 error = aa_setup_dfa_engine();
2223 if (error) {
2224 AA_ERROR("Unable to setup dfa engine\n");
2225 goto alloc_out;
2226 }
2227
2228 error = aa_alloc_root_ns();
2229 if (error) {
2230 AA_ERROR("Unable to allocate default profile namespace\n");
2231 goto alloc_out;
2232 }
2233
2234 error = apparmor_init_sysctl();
2235 if (error) {
2236 AA_ERROR("Unable to register sysctls\n");
2237 goto alloc_out;
2238
2239 }
2240
2241 error = alloc_buffers();
2242 if (error) {
2243 AA_ERROR("Unable to allocate work buffers\n");
2244 goto alloc_out;
2245 }
2246
2247 error = set_init_ctx();
2248 if (error) {
2249 AA_ERROR("Failed to set context on init task\n");
2250 aa_free_root_ns();
2251 goto buffers_out;
2252 }
2253 security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
2254 &apparmor_lsmid);
2255
2256 /* Report that AppArmor successfully initialized */
2257 apparmor_initialized = 1;
2258 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
2259 aa_info_message("AppArmor initialized: complain mode enabled");
2260 else if (aa_g_profile_mode == APPARMOR_KILL)
2261 aa_info_message("AppArmor initialized: kill mode enabled");
2262 else
2263 aa_info_message("AppArmor initialized");
2264
2265 return error;
2266
2267buffers_out:
2268 destroy_buffers();
2269alloc_out:
2270 aa_destroy_aafs();
2271 aa_teardown_dfa_engine();
2272
2273 apparmor_enabled = false;
2274 return error;
2275}
2276
2277DEFINE_LSM(apparmor) = {
2278 .name = "apparmor",
2279 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
2280 .enabled = &apparmor_enabled,
2281 .blobs = &apparmor_blob_sizes,
2282 .init = apparmor_init,
2283};