1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Task credentials management - see Documentation/security/credentials.rst
3 *
4 * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8 #define pr_fmt(fmt) "CRED: " fmt
9
10 #include <linux/export.h>
11 #include <linux/cred.h>
12 #include <linux/slab.h>
13 #include <linux/sched.h>
14 #include <linux/sched/coredump.h>
15 #include <linux/key.h>
16 #include <linux/keyctl.h>
17 #include <linux/init_task.h>
18 #include <linux/security.h>
19 #include <linux/binfmts.h>
20 #include <linux/cn_proc.h>
21 #include <linux/uidgid.h>
22
23 #if 0
24 #define kdebug(FMT, ...) \
25 printk("[%-5.5s%5u] " FMT "\n", \
26 current->comm, current->pid, ##__VA_ARGS__)
27 #else
28 #define kdebug(FMT, ...) \
29 do { \
30 if (0) \
31 no_printk("[%-5.5s%5u] " FMT "\n", \
32 current->comm, current->pid, ##__VA_ARGS__); \
33 } while (0)
34 #endif
35
36 static struct kmem_cache *cred_jar;
37
38 /* init to 2 - one for init_task, one to ensure it is never freed */
39 static struct group_info init_groups = { .usage = ATOMIC_INIT(2) };
40
41 /*
42 * The initial credentials for the initial task
43 */
44 struct cred init_cred = {
45 .usage = ATOMIC_INIT(4),
46 .uid = GLOBAL_ROOT_UID,
47 .gid = GLOBAL_ROOT_GID,
48 .suid = GLOBAL_ROOT_UID,
49 .sgid = GLOBAL_ROOT_GID,
50 .euid = GLOBAL_ROOT_UID,
51 .egid = GLOBAL_ROOT_GID,
52 .fsuid = GLOBAL_ROOT_UID,
53 .fsgid = GLOBAL_ROOT_GID,
54 .securebits = SECUREBITS_DEFAULT,
55 .cap_inheritable = CAP_EMPTY_SET,
56 .cap_permitted = CAP_FULL_SET,
57 .cap_effective = CAP_FULL_SET,
58 .cap_bset = CAP_FULL_SET,
59 .user = INIT_USER,
60 .user_ns = &init_user_ns,
61 .group_info = &init_groups,
62 .ucounts = &init_ucounts,
63 };
64
65 /*
66 * The RCU callback to actually dispose of a set of credentials
67 */
put_cred_rcu(struct rcu_head * rcu)68 static void put_cred_rcu(struct rcu_head *rcu)
69 {
70 struct cred *cred = container_of(rcu, struct cred, rcu);
71
72 kdebug("put_cred_rcu(%p)", cred);
73
74 if (atomic_long_read(&cred->usage) != 0)
75 panic("CRED: put_cred_rcu() sees %p with usage %ld\n",
76 cred, atomic_long_read(&cred->usage));
77
78 security_cred_free(cred);
79 key_put(cred->session_keyring);
80 key_put(cred->process_keyring);
81 key_put(cred->thread_keyring);
82 key_put(cred->request_key_auth);
83 if (cred->group_info)
84 put_group_info(cred->group_info);
85 free_uid(cred->user);
86 if (cred->ucounts)
87 put_ucounts(cred->ucounts);
88 put_user_ns(cred->user_ns);
89 kmem_cache_free(cred_jar, cred);
90 }
91
92 /**
93 * __put_cred - Destroy a set of credentials
94 * @cred: The record to release
95 *
96 * Destroy a set of credentials on which no references remain.
97 */
__put_cred(struct cred * cred)98 void __put_cred(struct cred *cred)
99 {
100 kdebug("__put_cred(%p{%ld})", cred,
101 atomic_long_read(&cred->usage));
102
103 BUG_ON(atomic_long_read(&cred->usage) != 0);
104 BUG_ON(cred == current->cred);
105 BUG_ON(cred == current->real_cred);
106
107 if (cred->non_rcu)
108 put_cred_rcu(&cred->rcu);
109 else
110 call_rcu(&cred->rcu, put_cred_rcu);
111 }
112 EXPORT_SYMBOL(__put_cred);
113
114 /*
115 * Clean up a task's credentials when it exits
116 */
exit_creds(struct task_struct * tsk)117 void exit_creds(struct task_struct *tsk)
118 {
119 struct cred *cred;
120
121 kdebug("exit_creds(%u,%p,%p,{%ld})", tsk->pid, tsk->real_cred, tsk->cred,
122 atomic_long_read(&tsk->cred->usage));
123
124 cred = (struct cred *) tsk->real_cred;
125 tsk->real_cred = NULL;
126 put_cred(cred);
127
128 cred = (struct cred *) tsk->cred;
129 tsk->cred = NULL;
130 put_cred(cred);
131
132 #ifdef CONFIG_KEYS_REQUEST_CACHE
133 key_put(tsk->cached_requested_key);
134 tsk->cached_requested_key = NULL;
135 #endif
136 }
137
138 /**
139 * get_task_cred - Get another task's objective credentials
140 * @task: The task to query
141 *
142 * Get the objective credentials of a task, pinning them so that they can't go
143 * away. Accessing a task's credentials directly is not permitted.
144 *
145 * The caller must also make sure task doesn't get deleted, either by holding a
146 * ref on task or by holding tasklist_lock to prevent it from being unlinked.
147 */
get_task_cred(struct task_struct * task)148 const struct cred *get_task_cred(struct task_struct *task)
149 {
150 const struct cred *cred;
151
152 rcu_read_lock();
153
154 do {
155 cred = __task_cred((task));
156 BUG_ON(!cred);
157 } while (!get_cred_rcu(cred));
158
159 rcu_read_unlock();
160 return cred;
161 }
162 EXPORT_SYMBOL(get_task_cred);
163
164 /*
165 * Allocate blank credentials, such that the credentials can be filled in at a
166 * later date without risk of ENOMEM.
167 */
cred_alloc_blank(void)168 struct cred *cred_alloc_blank(void)
169 {
170 struct cred *new;
171
172 new = kmem_cache_zalloc(cred_jar, GFP_KERNEL);
173 if (!new)
174 return NULL;
175
176 atomic_long_set(&new->usage, 1);
177 if (security_cred_alloc_blank(new, GFP_KERNEL_ACCOUNT) < 0)
178 goto error;
179
180 return new;
181
182 error:
183 abort_creds(new);
184 return NULL;
185 }
186
187 /**
188 * prepare_creds - Prepare a new set of credentials for modification
189 *
190 * Prepare a new set of task credentials for modification. A task's creds
191 * shouldn't generally be modified directly, therefore this function is used to
192 * prepare a new copy, which the caller then modifies and then commits by
193 * calling commit_creds().
194 *
195 * Preparation involves making a copy of the objective creds for modification.
196 *
197 * Returns a pointer to the new creds-to-be if successful, NULL otherwise.
198 *
199 * Call commit_creds() or abort_creds() to clean up.
200 */
prepare_creds(void)201 struct cred *prepare_creds(void)
202 {
203 struct task_struct *task = current;
204 const struct cred *old;
205 struct cred *new;
206
207 new = kmem_cache_alloc(cred_jar, GFP_KERNEL);
208 if (!new)
209 return NULL;
210
211 kdebug("prepare_creds() alloc %p", new);
212
213 old = task->cred;
214 memcpy(new, old, sizeof(struct cred));
215
216 new->non_rcu = 0;
217 atomic_long_set(&new->usage, 1);
218 get_group_info(new->group_info);
219 get_uid(new->user);
220 get_user_ns(new->user_ns);
221
222 #ifdef CONFIG_KEYS
223 key_get(new->session_keyring);
224 key_get(new->process_keyring);
225 key_get(new->thread_keyring);
226 key_get(new->request_key_auth);
227 #endif
228
229 #ifdef CONFIG_SECURITY
230 new->security = NULL;
231 #endif
232
233 new->ucounts = get_ucounts(new->ucounts);
234 if (!new->ucounts)
235 goto error;
236
237 if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
238 goto error;
239
240 return new;
241
242 error:
243 abort_creds(new);
244 return NULL;
245 }
246 EXPORT_SYMBOL(prepare_creds);
247
248 /*
249 * Prepare credentials for current to perform an execve()
250 * - The caller must hold ->cred_guard_mutex
251 */
prepare_exec_creds(void)252 struct cred *prepare_exec_creds(void)
253 {
254 struct cred *new;
255
256 new = prepare_creds();
257 if (!new)
258 return new;
259
260 #ifdef CONFIG_KEYS
261 /* newly exec'd tasks don't get a thread keyring */
262 key_put(new->thread_keyring);
263 new->thread_keyring = NULL;
264
265 /* inherit the session keyring; new process keyring */
266 key_put(new->process_keyring);
267 new->process_keyring = NULL;
268 #endif
269
270 new->suid = new->fsuid = new->euid;
271 new->sgid = new->fsgid = new->egid;
272
273 return new;
274 }
275
276 /*
277 * Copy credentials for the new process created by fork()
278 *
279 * We share if we can, but under some circumstances we have to generate a new
280 * set.
281 *
282 * The new process gets the current process's subjective credentials as its
283 * objective and subjective credentials
284 */
copy_creds(struct task_struct * p,unsigned long clone_flags)285 int copy_creds(struct task_struct *p, unsigned long clone_flags)
286 {
287 struct cred *new;
288 int ret;
289
290 #ifdef CONFIG_KEYS_REQUEST_CACHE
291 p->cached_requested_key = NULL;
292 #endif
293
294 if (
295 #ifdef CONFIG_KEYS
296 !p->cred->thread_keyring &&
297 #endif
298 clone_flags & CLONE_THREAD
299 ) {
300 p->real_cred = get_cred(p->cred);
301 get_cred(p->cred);
302 kdebug("share_creds(%p{%ld})",
303 p->cred, atomic_long_read(&p->cred->usage));
304 inc_rlimit_ucounts(task_ucounts(p), UCOUNT_RLIMIT_NPROC, 1);
305 return 0;
306 }
307
308 new = prepare_creds();
309 if (!new)
310 return -ENOMEM;
311
312 if (clone_flags & CLONE_NEWUSER) {
313 ret = create_user_ns(new);
314 if (ret < 0)
315 goto error_put;
316 ret = set_cred_ucounts(new);
317 if (ret < 0)
318 goto error_put;
319 }
320
321 #ifdef CONFIG_KEYS
322 /* new threads get their own thread keyrings if their parent already
323 * had one */
324 if (new->thread_keyring) {
325 key_put(new->thread_keyring);
326 new->thread_keyring = NULL;
327 if (clone_flags & CLONE_THREAD)
328 install_thread_keyring_to_cred(new);
329 }
330
331 /* The process keyring is only shared between the threads in a process;
332 * anything outside of those threads doesn't inherit.
333 */
334 if (!(clone_flags & CLONE_THREAD)) {
335 key_put(new->process_keyring);
336 new->process_keyring = NULL;
337 }
338 #endif
339
340 p->cred = p->real_cred = get_cred(new);
341 inc_rlimit_ucounts(task_ucounts(p), UCOUNT_RLIMIT_NPROC, 1);
342 return 0;
343
344 error_put:
345 put_cred(new);
346 return ret;
347 }
348
cred_cap_issubset(const struct cred * set,const struct cred * subset)349 static bool cred_cap_issubset(const struct cred *set, const struct cred *subset)
350 {
351 const struct user_namespace *set_ns = set->user_ns;
352 const struct user_namespace *subset_ns = subset->user_ns;
353
354 /* If the two credentials are in the same user namespace see if
355 * the capabilities of subset are a subset of set.
356 */
357 if (set_ns == subset_ns)
358 return cap_issubset(subset->cap_permitted, set->cap_permitted);
359
360 /* The credentials are in a different user namespaces
361 * therefore one is a subset of the other only if a set is an
362 * ancestor of subset and set->euid is owner of subset or one
363 * of subsets ancestors.
364 */
365 for (;subset_ns != &init_user_ns; subset_ns = subset_ns->parent) {
366 if ((set_ns == subset_ns->parent) &&
367 uid_eq(subset_ns->owner, set->euid))
368 return true;
369 }
370
371 return false;
372 }
373
374 /**
375 * commit_creds - Install new credentials upon the current task
376 * @new: The credentials to be assigned
377 *
378 * Install a new set of credentials to the current task, using RCU to replace
379 * the old set. Both the objective and the subjective credentials pointers are
380 * updated. This function may not be called if the subjective credentials are
381 * in an overridden state.
382 *
383 * This function eats the caller's reference to the new credentials.
384 *
385 * Always returns 0 thus allowing this function to be tail-called at the end
386 * of, say, sys_setgid().
387 */
commit_creds(struct cred * new)388 int commit_creds(struct cred *new)
389 {
390 struct task_struct *task = current;
391 const struct cred *old = task->real_cred;
392
393 kdebug("commit_creds(%p{%ld})", new,
394 atomic_long_read(&new->usage));
395
396 BUG_ON(task->cred != old);
397 BUG_ON(atomic_long_read(&new->usage) < 1);
398
399 get_cred(new); /* we will require a ref for the subj creds too */
400
401 /* dumpability changes */
402 if (!uid_eq(old->euid, new->euid) ||
403 !gid_eq(old->egid, new->egid) ||
404 !uid_eq(old->fsuid, new->fsuid) ||
405 !gid_eq(old->fsgid, new->fsgid) ||
406 !cred_cap_issubset(old, new)) {
407 if (task->mm)
408 set_dumpable(task->mm, suid_dumpable);
409 task->pdeath_signal = 0;
410 /*
411 * If a task drops privileges and becomes nondumpable,
412 * the dumpability change must become visible before
413 * the credential change; otherwise, a __ptrace_may_access()
414 * racing with this change may be able to attach to a task it
415 * shouldn't be able to attach to (as if the task had dropped
416 * privileges without becoming nondumpable).
417 * Pairs with a read barrier in __ptrace_may_access().
418 */
419 smp_wmb();
420 }
421
422 /* alter the thread keyring */
423 if (!uid_eq(new->fsuid, old->fsuid))
424 key_fsuid_changed(new);
425 if (!gid_eq(new->fsgid, old->fsgid))
426 key_fsgid_changed(new);
427
428 /* do it
429 * RLIMIT_NPROC limits on user->processes have already been checked
430 * in set_user().
431 */
432 if (new->user != old->user || new->user_ns != old->user_ns)
433 inc_rlimit_ucounts(new->ucounts, UCOUNT_RLIMIT_NPROC, 1);
434 rcu_assign_pointer(task->real_cred, new);
435 rcu_assign_pointer(task->cred, new);
436 if (new->user != old->user || new->user_ns != old->user_ns)
437 dec_rlimit_ucounts(old->ucounts, UCOUNT_RLIMIT_NPROC, 1);
438
439 /* send notifications */
440 if (!uid_eq(new->uid, old->uid) ||
441 !uid_eq(new->euid, old->euid) ||
442 !uid_eq(new->suid, old->suid) ||
443 !uid_eq(new->fsuid, old->fsuid))
444 proc_id_connector(task, PROC_EVENT_UID);
445
446 if (!gid_eq(new->gid, old->gid) ||
447 !gid_eq(new->egid, old->egid) ||
448 !gid_eq(new->sgid, old->sgid) ||
449 !gid_eq(new->fsgid, old->fsgid))
450 proc_id_connector(task, PROC_EVENT_GID);
451
452 /* release the old obj and subj refs both */
453 put_cred(old);
454 put_cred(old);
455 return 0;
456 }
457 EXPORT_SYMBOL(commit_creds);
458
459 /**
460 * abort_creds - Discard a set of credentials and unlock the current task
461 * @new: The credentials that were going to be applied
462 *
463 * Discard a set of credentials that were under construction and unlock the
464 * current task.
465 */
abort_creds(struct cred * new)466 void abort_creds(struct cred *new)
467 {
468 kdebug("abort_creds(%p{%ld})", new,
469 atomic_long_read(&new->usage));
470
471 BUG_ON(atomic_long_read(&new->usage) < 1);
472 put_cred(new);
473 }
474 EXPORT_SYMBOL(abort_creds);
475
476 /**
477 * override_creds - Override the current process's subjective credentials
478 * @new: The credentials to be assigned
479 *
480 * Install a set of temporary override subjective credentials on the current
481 * process, returning the old set for later reversion.
482 */
override_creds(const struct cred * new)483 const struct cred *override_creds(const struct cred *new)
484 {
485 const struct cred *old = current->cred;
486
487 kdebug("override_creds(%p{%ld})", new,
488 atomic_long_read(&new->usage));
489
490 /*
491 * NOTE! This uses 'get_new_cred()' rather than 'get_cred()'.
492 *
493 * That means that we do not clear the 'non_rcu' flag, since
494 * we are only installing the cred into the thread-synchronous
495 * '->cred' pointer, not the '->real_cred' pointer that is
496 * visible to other threads under RCU.
497 */
498 get_new_cred((struct cred *)new);
499 rcu_assign_pointer(current->cred, new);
500
501 kdebug("override_creds() = %p{%ld}", old,
502 atomic_long_read(&old->usage));
503 return old;
504 }
505 EXPORT_SYMBOL(override_creds);
506
507 /**
508 * revert_creds - Revert a temporary subjective credentials override
509 * @old: The credentials to be restored
510 *
511 * Revert a temporary set of override subjective credentials to an old set,
512 * discarding the override set.
513 */
revert_creds(const struct cred * old)514 void revert_creds(const struct cred *old)
515 {
516 const struct cred *override = current->cred;
517
518 kdebug("revert_creds(%p{%ld})", old,
519 atomic_long_read(&old->usage));
520
521 rcu_assign_pointer(current->cred, old);
522 put_cred(override);
523 }
524 EXPORT_SYMBOL(revert_creds);
525
526 /**
527 * cred_fscmp - Compare two credentials with respect to filesystem access.
528 * @a: The first credential
529 * @b: The second credential
530 *
531 * cred_cmp() will return zero if both credentials have the same
532 * fsuid, fsgid, and supplementary groups. That is, if they will both
533 * provide the same access to files based on mode/uid/gid.
534 * If the credentials are different, then either -1 or 1 will
535 * be returned depending on whether @a comes before or after @b
536 * respectively in an arbitrary, but stable, ordering of credentials.
537 *
538 * Return: -1, 0, or 1 depending on comparison
539 */
cred_fscmp(const struct cred * a,const struct cred * b)540 int cred_fscmp(const struct cred *a, const struct cred *b)
541 {
542 struct group_info *ga, *gb;
543 int g;
544
545 if (a == b)
546 return 0;
547 if (uid_lt(a->fsuid, b->fsuid))
548 return -1;
549 if (uid_gt(a->fsuid, b->fsuid))
550 return 1;
551
552 if (gid_lt(a->fsgid, b->fsgid))
553 return -1;
554 if (gid_gt(a->fsgid, b->fsgid))
555 return 1;
556
557 ga = a->group_info;
558 gb = b->group_info;
559 if (ga == gb)
560 return 0;
561 if (ga == NULL)
562 return -1;
563 if (gb == NULL)
564 return 1;
565 if (ga->ngroups < gb->ngroups)
566 return -1;
567 if (ga->ngroups > gb->ngroups)
568 return 1;
569
570 for (g = 0; g < ga->ngroups; g++) {
571 if (gid_lt(ga->gid[g], gb->gid[g]))
572 return -1;
573 if (gid_gt(ga->gid[g], gb->gid[g]))
574 return 1;
575 }
576 return 0;
577 }
578 EXPORT_SYMBOL(cred_fscmp);
579
set_cred_ucounts(struct cred * new)580 int set_cred_ucounts(struct cred *new)
581 {
582 struct ucounts *new_ucounts, *old_ucounts = new->ucounts;
583
584 /*
585 * This optimization is needed because alloc_ucounts() uses locks
586 * for table lookups.
587 */
588 if (old_ucounts->ns == new->user_ns && uid_eq(old_ucounts->uid, new->uid))
589 return 0;
590
591 if (!(new_ucounts = alloc_ucounts(new->user_ns, new->uid)))
592 return -EAGAIN;
593
594 new->ucounts = new_ucounts;
595 put_ucounts(old_ucounts);
596
597 return 0;
598 }
599
600 /*
601 * initialise the credentials stuff
602 */
cred_init(void)603 void __init cred_init(void)
604 {
605 /* allocate a slab in which we can store credentials */
606 cred_jar = kmem_cache_create("cred_jar", sizeof(struct cred), 0,
607 SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT, NULL);
608 }
609
610 /**
611 * prepare_kernel_cred - Prepare a set of credentials for a kernel service
612 * @daemon: A userspace daemon to be used as a reference
613 *
614 * Prepare a set of credentials for a kernel service. This can then be used to
615 * override a task's own credentials so that work can be done on behalf of that
616 * task that requires a different subjective context.
617 *
618 * @daemon is used to provide a base cred, with the security data derived from
619 * that; if this is "&init_task", they'll be set to 0, no groups, full
620 * capabilities, and no keys.
621 *
622 * The caller may change these controls afterwards if desired.
623 *
624 * Returns the new credentials or NULL if out of memory.
625 */
prepare_kernel_cred(struct task_struct * daemon)626 struct cred *prepare_kernel_cred(struct task_struct *daemon)
627 {
628 const struct cred *old;
629 struct cred *new;
630
631 if (WARN_ON_ONCE(!daemon))
632 return NULL;
633
634 new = kmem_cache_alloc(cred_jar, GFP_KERNEL);
635 if (!new)
636 return NULL;
637
638 kdebug("prepare_kernel_cred() alloc %p", new);
639
640 old = get_task_cred(daemon);
641
642 *new = *old;
643 new->non_rcu = 0;
644 atomic_long_set(&new->usage, 1);
645 get_uid(new->user);
646 get_user_ns(new->user_ns);
647 get_group_info(new->group_info);
648
649 #ifdef CONFIG_KEYS
650 new->session_keyring = NULL;
651 new->process_keyring = NULL;
652 new->thread_keyring = NULL;
653 new->request_key_auth = NULL;
654 new->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
655 #endif
656
657 #ifdef CONFIG_SECURITY
658 new->security = NULL;
659 #endif
660 new->ucounts = get_ucounts(new->ucounts);
661 if (!new->ucounts)
662 goto error;
663
664 if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
665 goto error;
666
667 put_cred(old);
668 return new;
669
670 error:
671 put_cred(new);
672 put_cred(old);
673 return NULL;
674 }
675 EXPORT_SYMBOL(prepare_kernel_cred);
676
677 /**
678 * set_security_override - Set the security ID in a set of credentials
679 * @new: The credentials to alter
680 * @secid: The LSM security ID to set
681 *
682 * Set the LSM security ID in a set of credentials so that the subjective
683 * security is overridden when an alternative set of credentials is used.
684 */
set_security_override(struct cred * new,u32 secid)685 int set_security_override(struct cred *new, u32 secid)
686 {
687 return security_kernel_act_as(new, secid);
688 }
689 EXPORT_SYMBOL(set_security_override);
690
691 /**
692 * set_security_override_from_ctx - Set the security ID in a set of credentials
693 * @new: The credentials to alter
694 * @secctx: The LSM security context to generate the security ID from.
695 *
696 * Set the LSM security ID in a set of credentials so that the subjective
697 * security is overridden when an alternative set of credentials is used. The
698 * security ID is specified in string form as a security context to be
699 * interpreted by the LSM.
700 */
set_security_override_from_ctx(struct cred * new,const char * secctx)701 int set_security_override_from_ctx(struct cred *new, const char *secctx)
702 {
703 u32 secid;
704 int ret;
705
706 ret = security_secctx_to_secid(secctx, strlen(secctx), &secid);
707 if (ret < 0)
708 return ret;
709
710 return set_security_override(new, secid);
711 }
712 EXPORT_SYMBOL(set_security_override_from_ctx);
713
714 /**
715 * set_create_files_as - Set the LSM file create context in a set of credentials
716 * @new: The credentials to alter
717 * @inode: The inode to take the context from
718 *
719 * Change the LSM file creation context in a set of credentials to be the same
720 * as the object context of the specified inode, so that the new inodes have
721 * the same MAC context as that inode.
722 */
set_create_files_as(struct cred * new,struct inode * inode)723 int set_create_files_as(struct cred *new, struct inode *inode)
724 {
725 if (!uid_valid(inode->i_uid) || !gid_valid(inode->i_gid))
726 return -EINVAL;
727 new->fsuid = inode->i_uid;
728 new->fsgid = inode->i_gid;
729 return security_kernel_create_files_as(new, inode);
730 }
731 EXPORT_SYMBOL(set_create_files_as);
732