1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Task credentials management - see Documentation/security/credentials.rst
4 * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
7 #include <linux/export.h>
8 #include <linux/cred.h>
9 #include <linux/slab.h>
10 #include <linux/sched.h>
11 #include <linux/sched/coredump.h>
12 #include <linux/key.h>
13 #include <linux/keyctl.h>
14 #include <linux/init_task.h>
15 #include <linux/security.h>
16 #include <linux/binfmts.h>
17 #include <linux/cn_proc.h>
18 #include <linux/uidgid.h>
21 #define kdebug(FMT, ...) \
22 printk("[%-5.5s%5u] " FMT "\n", \
23 current->comm, current->pid, ##__VA_ARGS__)
25 #define kdebug(FMT, ...) \
28 no_printk("[%-5.5s%5u] " FMT "\n", \
29 current->comm, current->pid, ##__VA_ARGS__); \
33 static struct kmem_cache
*cred_jar
;
35 /* init to 2 - one for init_task, one to ensure it is never freed */
36 struct group_info init_groups
= { .usage
= ATOMIC_INIT(2) };
39 * The initial credentials for the initial task
41 struct cred init_cred
= {
42 .usage
= ATOMIC_INIT(4),
43 #ifdef CONFIG_DEBUG_CREDENTIALS
44 .subscribers
= ATOMIC_INIT(2),
47 .uid
= GLOBAL_ROOT_UID
,
48 .gid
= GLOBAL_ROOT_GID
,
49 .suid
= GLOBAL_ROOT_UID
,
50 .sgid
= GLOBAL_ROOT_GID
,
51 .euid
= GLOBAL_ROOT_UID
,
52 .egid
= GLOBAL_ROOT_GID
,
53 .fsuid
= GLOBAL_ROOT_UID
,
54 .fsgid
= GLOBAL_ROOT_GID
,
55 .securebits
= SECUREBITS_DEFAULT
,
56 .cap_inheritable
= CAP_EMPTY_SET
,
57 .cap_permitted
= CAP_FULL_SET
,
58 .cap_effective
= CAP_FULL_SET
,
59 .cap_bset
= CAP_FULL_SET
,
61 .user_ns
= &init_user_ns
,
62 .group_info
= &init_groups
,
65 static inline void set_cred_subscribers(struct cred
*cred
, int n
)
67 #ifdef CONFIG_DEBUG_CREDENTIALS
68 atomic_set(&cred
->subscribers
, n
);
72 static inline int read_cred_subscribers(const struct cred
*cred
)
74 #ifdef CONFIG_DEBUG_CREDENTIALS
75 return atomic_read(&cred
->subscribers
);
81 static inline void alter_cred_subscribers(const struct cred
*_cred
, int n
)
83 #ifdef CONFIG_DEBUG_CREDENTIALS
84 struct cred
*cred
= (struct cred
*) _cred
;
86 atomic_add(n
, &cred
->subscribers
);
91 * The RCU callback to actually dispose of a set of credentials
93 static void put_cred_rcu(struct rcu_head
*rcu
)
95 struct cred
*cred
= container_of(rcu
, struct cred
, rcu
);
97 kdebug("put_cred_rcu(%p)", cred
);
99 #ifdef CONFIG_DEBUG_CREDENTIALS
100 if (cred
->magic
!= CRED_MAGIC_DEAD
||
101 atomic_read(&cred
->usage
) != 0 ||
102 read_cred_subscribers(cred
) != 0)
103 panic("CRED: put_cred_rcu() sees %p with"
104 " mag %x, put %p, usage %d, subscr %d\n",
105 cred
, cred
->magic
, cred
->put_addr
,
106 atomic_read(&cred
->usage
),
107 read_cred_subscribers(cred
));
109 if (atomic_read(&cred
->usage
) != 0)
110 panic("CRED: put_cred_rcu() sees %p with usage %d\n",
111 cred
, atomic_read(&cred
->usage
));
114 security_cred_free(cred
);
115 key_put(cred
->session_keyring
);
116 key_put(cred
->process_keyring
);
117 key_put(cred
->thread_keyring
);
118 key_put(cred
->request_key_auth
);
119 if (cred
->group_info
)
120 put_group_info(cred
->group_info
);
121 free_uid(cred
->user
);
122 put_user_ns(cred
->user_ns
);
123 kmem_cache_free(cred_jar
, cred
);
127 * __put_cred - Destroy a set of credentials
128 * @cred: The record to release
130 * Destroy a set of credentials on which no references remain.
132 void __put_cred(struct cred
*cred
)
134 kdebug("__put_cred(%p{%d,%d})", cred
,
135 atomic_read(&cred
->usage
),
136 read_cred_subscribers(cred
));
138 BUG_ON(atomic_read(&cred
->usage
) != 0);
139 #ifdef CONFIG_DEBUG_CREDENTIALS
140 BUG_ON(read_cred_subscribers(cred
) != 0);
141 cred
->magic
= CRED_MAGIC_DEAD
;
142 cred
->put_addr
= __builtin_return_address(0);
144 BUG_ON(cred
== current
->cred
);
145 BUG_ON(cred
== current
->real_cred
);
147 call_rcu(&cred
->rcu
, put_cred_rcu
);
149 EXPORT_SYMBOL(__put_cred
);
152 * Clean up a task's credentials when it exits
154 void exit_creds(struct task_struct
*tsk
)
158 kdebug("exit_creds(%u,%p,%p,{%d,%d})", tsk
->pid
, tsk
->real_cred
, tsk
->cred
,
159 atomic_read(&tsk
->cred
->usage
),
160 read_cred_subscribers(tsk
->cred
));
162 cred
= (struct cred
*) tsk
->real_cred
;
163 tsk
->real_cred
= NULL
;
164 validate_creds(cred
);
165 alter_cred_subscribers(cred
, -1);
168 cred
= (struct cred
*) tsk
->cred
;
170 validate_creds(cred
);
171 alter_cred_subscribers(cred
, -1);
174 #ifdef CONFIG_KEYS_REQUEST_CACHE
175 key_put(current
->cached_requested_key
);
176 current
->cached_requested_key
= NULL
;
181 * get_task_cred - Get another task's objective credentials
182 * @task: The task to query
184 * Get the objective credentials of a task, pinning them so that they can't go
185 * away. Accessing a task's credentials directly is not permitted.
187 * The caller must also make sure task doesn't get deleted, either by holding a
188 * ref on task or by holding tasklist_lock to prevent it from being unlinked.
190 const struct cred
*get_task_cred(struct task_struct
*task
)
192 const struct cred
*cred
;
197 cred
= __task_cred((task
));
199 } while (!get_cred_rcu(cred
));
204 EXPORT_SYMBOL(get_task_cred
);
207 * Allocate blank credentials, such that the credentials can be filled in at a
208 * later date without risk of ENOMEM.
210 struct cred
*cred_alloc_blank(void)
214 new = kmem_cache_zalloc(cred_jar
, GFP_KERNEL
);
218 atomic_set(&new->usage
, 1);
219 #ifdef CONFIG_DEBUG_CREDENTIALS
220 new->magic
= CRED_MAGIC
;
223 if (security_cred_alloc_blank(new, GFP_KERNEL
) < 0)
234 * prepare_creds - Prepare a new set of credentials for modification
236 * Prepare a new set of task credentials for modification. A task's creds
237 * shouldn't generally be modified directly, therefore this function is used to
238 * prepare a new copy, which the caller then modifies and then commits by
239 * calling commit_creds().
241 * Preparation involves making a copy of the objective creds for modification.
243 * Returns a pointer to the new creds-to-be if successful, NULL otherwise.
245 * Call commit_creds() or abort_creds() to clean up.
247 struct cred
*prepare_creds(void)
249 struct task_struct
*task
= current
;
250 const struct cred
*old
;
253 validate_process_creds();
255 new = kmem_cache_alloc(cred_jar
, GFP_KERNEL
);
259 kdebug("prepare_creds() alloc %p", new);
262 memcpy(new, old
, sizeof(struct cred
));
264 atomic_set(&new->usage
, 1);
265 set_cred_subscribers(new, 0);
266 get_group_info(new->group_info
);
268 get_user_ns(new->user_ns
);
271 key_get(new->session_keyring
);
272 key_get(new->process_keyring
);
273 key_get(new->thread_keyring
);
274 key_get(new->request_key_auth
);
277 #ifdef CONFIG_SECURITY
278 new->security
= NULL
;
281 if (security_prepare_creds(new, old
, GFP_KERNEL
) < 0)
290 EXPORT_SYMBOL(prepare_creds
);
293 * Prepare credentials for current to perform an execve()
294 * - The caller must hold ->cred_guard_mutex
296 struct cred
*prepare_exec_creds(void)
300 new = prepare_creds();
305 /* newly exec'd tasks don't get a thread keyring */
306 key_put(new->thread_keyring
);
307 new->thread_keyring
= NULL
;
309 /* inherit the session keyring; new process keyring */
310 key_put(new->process_keyring
);
311 new->process_keyring
= NULL
;
318 * Copy credentials for the new process created by fork()
320 * We share if we can, but under some circumstances we have to generate a new
323 * The new process gets the current process's subjective credentials as its
324 * objective and subjective credentials
326 int copy_creds(struct task_struct
*p
, unsigned long clone_flags
)
331 #ifdef CONFIG_KEYS_REQUEST_CACHE
332 p
->cached_requested_key
= NULL
;
337 !p
->cred
->thread_keyring
&&
339 clone_flags
& CLONE_THREAD
341 p
->real_cred
= get_cred(p
->cred
);
343 alter_cred_subscribers(p
->cred
, 2);
344 kdebug("share_creds(%p{%d,%d})",
345 p
->cred
, atomic_read(&p
->cred
->usage
),
346 read_cred_subscribers(p
->cred
));
347 atomic_inc(&p
->cred
->user
->processes
);
351 new = prepare_creds();
355 if (clone_flags
& CLONE_NEWUSER
) {
356 ret
= create_user_ns(new);
362 /* new threads get their own thread keyrings if their parent already
364 if (new->thread_keyring
) {
365 key_put(new->thread_keyring
);
366 new->thread_keyring
= NULL
;
367 if (clone_flags
& CLONE_THREAD
)
368 install_thread_keyring_to_cred(new);
371 /* The process keyring is only shared between the threads in a process;
372 * anything outside of those threads doesn't inherit.
374 if (!(clone_flags
& CLONE_THREAD
)) {
375 key_put(new->process_keyring
);
376 new->process_keyring
= NULL
;
380 atomic_inc(&new->user
->processes
);
381 p
->cred
= p
->real_cred
= get_cred(new);
382 alter_cred_subscribers(new, 2);
391 static bool cred_cap_issubset(const struct cred
*set
, const struct cred
*subset
)
393 const struct user_namespace
*set_ns
= set
->user_ns
;
394 const struct user_namespace
*subset_ns
= subset
->user_ns
;
396 /* If the two credentials are in the same user namespace see if
397 * the capabilities of subset are a subset of set.
399 if (set_ns
== subset_ns
)
400 return cap_issubset(subset
->cap_permitted
, set
->cap_permitted
);
402 /* The credentials are in a different user namespaces
403 * therefore one is a subset of the other only if a set is an
404 * ancestor of subset and set->euid is owner of subset or one
405 * of subsets ancestors.
407 for (;subset_ns
!= &init_user_ns
; subset_ns
= subset_ns
->parent
) {
408 if ((set_ns
== subset_ns
->parent
) &&
409 uid_eq(subset_ns
->owner
, set
->euid
))
417 * commit_creds - Install new credentials upon the current task
418 * @new: The credentials to be assigned
420 * Install a new set of credentials to the current task, using RCU to replace
421 * the old set. Both the objective and the subjective credentials pointers are
422 * updated. This function may not be called if the subjective credentials are
423 * in an overridden state.
425 * This function eats the caller's reference to the new credentials.
427 * Always returns 0 thus allowing this function to be tail-called at the end
428 * of, say, sys_setgid().
430 int commit_creds(struct cred
*new)
432 struct task_struct
*task
= current
;
433 const struct cred
*old
= task
->real_cred
;
435 kdebug("commit_creds(%p{%d,%d})", new,
436 atomic_read(&new->usage
),
437 read_cred_subscribers(new));
439 BUG_ON(task
->cred
!= old
);
440 #ifdef CONFIG_DEBUG_CREDENTIALS
441 BUG_ON(read_cred_subscribers(old
) < 2);
445 BUG_ON(atomic_read(&new->usage
) < 1);
447 get_cred(new); /* we will require a ref for the subj creds too */
449 /* dumpability changes */
450 if (!uid_eq(old
->euid
, new->euid
) ||
451 !gid_eq(old
->egid
, new->egid
) ||
452 !uid_eq(old
->fsuid
, new->fsuid
) ||
453 !gid_eq(old
->fsgid
, new->fsgid
) ||
454 !cred_cap_issubset(old
, new)) {
456 set_dumpable(task
->mm
, suid_dumpable
);
457 task
->pdeath_signal
= 0;
459 * If a task drops privileges and becomes nondumpable,
460 * the dumpability change must become visible before
461 * the credential change; otherwise, a __ptrace_may_access()
462 * racing with this change may be able to attach to a task it
463 * shouldn't be able to attach to (as if the task had dropped
464 * privileges without becoming nondumpable).
465 * Pairs with a read barrier in __ptrace_may_access().
470 /* alter the thread keyring */
471 if (!uid_eq(new->fsuid
, old
->fsuid
))
472 key_fsuid_changed(new);
473 if (!gid_eq(new->fsgid
, old
->fsgid
))
474 key_fsgid_changed(new);
477 * RLIMIT_NPROC limits on user->processes have already been checked
480 alter_cred_subscribers(new, 2);
481 if (new->user
!= old
->user
)
482 atomic_inc(&new->user
->processes
);
483 rcu_assign_pointer(task
->real_cred
, new);
484 rcu_assign_pointer(task
->cred
, new);
485 if (new->user
!= old
->user
)
486 atomic_dec(&old
->user
->processes
);
487 alter_cred_subscribers(old
, -2);
489 /* send notifications */
490 if (!uid_eq(new->uid
, old
->uid
) ||
491 !uid_eq(new->euid
, old
->euid
) ||
492 !uid_eq(new->suid
, old
->suid
) ||
493 !uid_eq(new->fsuid
, old
->fsuid
))
494 proc_id_connector(task
, PROC_EVENT_UID
);
496 if (!gid_eq(new->gid
, old
->gid
) ||
497 !gid_eq(new->egid
, old
->egid
) ||
498 !gid_eq(new->sgid
, old
->sgid
) ||
499 !gid_eq(new->fsgid
, old
->fsgid
))
500 proc_id_connector(task
, PROC_EVENT_GID
);
502 /* release the old obj and subj refs both */
507 EXPORT_SYMBOL(commit_creds
);
510 * abort_creds - Discard a set of credentials and unlock the current task
511 * @new: The credentials that were going to be applied
513 * Discard a set of credentials that were under construction and unlock the
516 void abort_creds(struct cred
*new)
518 kdebug("abort_creds(%p{%d,%d})", new,
519 atomic_read(&new->usage
),
520 read_cred_subscribers(new));
522 #ifdef CONFIG_DEBUG_CREDENTIALS
523 BUG_ON(read_cred_subscribers(new) != 0);
525 BUG_ON(atomic_read(&new->usage
) < 1);
528 EXPORT_SYMBOL(abort_creds
);
531 * override_creds - Override the current process's subjective credentials
532 * @new: The credentials to be assigned
534 * Install a set of temporary override subjective credentials on the current
535 * process, returning the old set for later reversion.
537 const struct cred
*override_creds(const struct cred
*new)
539 const struct cred
*old
= current
->cred
;
541 kdebug("override_creds(%p{%d,%d})", new,
542 atomic_read(&new->usage
),
543 read_cred_subscribers(new));
548 alter_cred_subscribers(new, 1);
549 rcu_assign_pointer(current
->cred
, new);
550 alter_cred_subscribers(old
, -1);
552 kdebug("override_creds() = %p{%d,%d}", old
,
553 atomic_read(&old
->usage
),
554 read_cred_subscribers(old
));
557 EXPORT_SYMBOL(override_creds
);
560 * revert_creds - Revert a temporary subjective credentials override
561 * @old: The credentials to be restored
563 * Revert a temporary set of override subjective credentials to an old set,
564 * discarding the override set.
566 void revert_creds(const struct cred
*old
)
568 const struct cred
*override
= current
->cred
;
570 kdebug("revert_creds(%p{%d,%d})", old
,
571 atomic_read(&old
->usage
),
572 read_cred_subscribers(old
));
575 validate_creds(override
);
576 alter_cred_subscribers(old
, 1);
577 rcu_assign_pointer(current
->cred
, old
);
578 alter_cred_subscribers(override
, -1);
581 EXPORT_SYMBOL(revert_creds
);
584 * cred_fscmp - Compare two credentials with respect to filesystem access.
585 * @a: The first credential
586 * @b: The second credential
588 * cred_cmp() will return zero if both credentials have the same
589 * fsuid, fsgid, and supplementary groups. That is, if they will both
590 * provide the same access to files based on mode/uid/gid.
591 * If the credentials are different, then either -1 or 1 will
592 * be returned depending on whether @a comes before or after @b
593 * respectively in an arbitrary, but stable, ordering of credentials.
595 * Return: -1, 0, or 1 depending on comparison
597 int cred_fscmp(const struct cred
*a
, const struct cred
*b
)
599 struct group_info
*ga
, *gb
;
604 if (uid_lt(a
->fsuid
, b
->fsuid
))
606 if (uid_gt(a
->fsuid
, b
->fsuid
))
609 if (gid_lt(a
->fsgid
, b
->fsgid
))
611 if (gid_gt(a
->fsgid
, b
->fsgid
))
622 if (ga
->ngroups
< gb
->ngroups
)
624 if (ga
->ngroups
> gb
->ngroups
)
627 for (g
= 0; g
< ga
->ngroups
; g
++) {
628 if (gid_lt(ga
->gid
[g
], gb
->gid
[g
]))
630 if (gid_gt(ga
->gid
[g
], gb
->gid
[g
]))
635 EXPORT_SYMBOL(cred_fscmp
);
638 * initialise the credentials stuff
640 void __init
cred_init(void)
642 /* allocate a slab in which we can store credentials */
643 cred_jar
= kmem_cache_create("cred_jar", sizeof(struct cred
), 0,
644 SLAB_HWCACHE_ALIGN
|SLAB_PANIC
|SLAB_ACCOUNT
, NULL
);
648 * prepare_kernel_cred - Prepare a set of credentials for a kernel service
649 * @daemon: A userspace daemon to be used as a reference
651 * Prepare a set of credentials for a kernel service. This can then be used to
652 * override a task's own credentials so that work can be done on behalf of that
653 * task that requires a different subjective context.
655 * @daemon is used to provide a base for the security record, but can be NULL.
656 * If @daemon is supplied, then the security data will be derived from that;
657 * otherwise they'll be set to 0 and no groups, full capabilities and no keys.
659 * The caller may change these controls afterwards if desired.
661 * Returns the new credentials or NULL if out of memory.
663 * Does not take, and does not return holding current->cred_replace_mutex.
665 struct cred
*prepare_kernel_cred(struct task_struct
*daemon
)
667 const struct cred
*old
;
670 new = kmem_cache_alloc(cred_jar
, GFP_KERNEL
);
674 kdebug("prepare_kernel_cred() alloc %p", new);
677 old
= get_task_cred(daemon
);
679 old
= get_cred(&init_cred
);
684 atomic_set(&new->usage
, 1);
685 set_cred_subscribers(new, 0);
687 get_user_ns(new->user_ns
);
688 get_group_info(new->group_info
);
691 new->session_keyring
= NULL
;
692 new->process_keyring
= NULL
;
693 new->thread_keyring
= NULL
;
694 new->request_key_auth
= NULL
;
695 new->jit_keyring
= KEY_REQKEY_DEFL_THREAD_KEYRING
;
698 #ifdef CONFIG_SECURITY
699 new->security
= NULL
;
701 if (security_prepare_creds(new, old
, GFP_KERNEL
) < 0)
713 EXPORT_SYMBOL(prepare_kernel_cred
);
716 * set_security_override - Set the security ID in a set of credentials
717 * @new: The credentials to alter
718 * @secid: The LSM security ID to set
720 * Set the LSM security ID in a set of credentials so that the subjective
721 * security is overridden when an alternative set of credentials is used.
723 int set_security_override(struct cred
*new, u32 secid
)
725 return security_kernel_act_as(new, secid
);
727 EXPORT_SYMBOL(set_security_override
);
730 * set_security_override_from_ctx - Set the security ID in a set of credentials
731 * @new: The credentials to alter
732 * @secctx: The LSM security context to generate the security ID from.
734 * Set the LSM security ID in a set of credentials so that the subjective
735 * security is overridden when an alternative set of credentials is used. The
736 * security ID is specified in string form as a security context to be
737 * interpreted by the LSM.
739 int set_security_override_from_ctx(struct cred
*new, const char *secctx
)
744 ret
= security_secctx_to_secid(secctx
, strlen(secctx
), &secid
);
748 return set_security_override(new, secid
);
750 EXPORT_SYMBOL(set_security_override_from_ctx
);
753 * set_create_files_as - Set the LSM file create context in a set of credentials
754 * @new: The credentials to alter
755 * @inode: The inode to take the context from
757 * Change the LSM file creation context in a set of credentials to be the same
758 * as the object context of the specified inode, so that the new inodes have
759 * the same MAC context as that inode.
761 int set_create_files_as(struct cred
*new, struct inode
*inode
)
763 if (!uid_valid(inode
->i_uid
) || !gid_valid(inode
->i_gid
))
765 new->fsuid
= inode
->i_uid
;
766 new->fsgid
= inode
->i_gid
;
767 return security_kernel_create_files_as(new, inode
);
769 EXPORT_SYMBOL(set_create_files_as
);
771 #ifdef CONFIG_DEBUG_CREDENTIALS
773 bool creds_are_invalid(const struct cred
*cred
)
775 if (cred
->magic
!= CRED_MAGIC
)
779 EXPORT_SYMBOL(creds_are_invalid
);
782 * dump invalid credentials
784 static void dump_invalid_creds(const struct cred
*cred
, const char *label
,
785 const struct task_struct
*tsk
)
787 printk(KERN_ERR
"CRED: %s credentials: %p %s%s%s\n",
789 cred
== &init_cred
? "[init]" : "",
790 cred
== tsk
->real_cred
? "[real]" : "",
791 cred
== tsk
->cred
? "[eff]" : "");
792 printk(KERN_ERR
"CRED: ->magic=%x, put_addr=%p\n",
793 cred
->magic
, cred
->put_addr
);
794 printk(KERN_ERR
"CRED: ->usage=%d, subscr=%d\n",
795 atomic_read(&cred
->usage
),
796 read_cred_subscribers(cred
));
797 printk(KERN_ERR
"CRED: ->*uid = { %d,%d,%d,%d }\n",
798 from_kuid_munged(&init_user_ns
, cred
->uid
),
799 from_kuid_munged(&init_user_ns
, cred
->euid
),
800 from_kuid_munged(&init_user_ns
, cred
->suid
),
801 from_kuid_munged(&init_user_ns
, cred
->fsuid
));
802 printk(KERN_ERR
"CRED: ->*gid = { %d,%d,%d,%d }\n",
803 from_kgid_munged(&init_user_ns
, cred
->gid
),
804 from_kgid_munged(&init_user_ns
, cred
->egid
),
805 from_kgid_munged(&init_user_ns
, cred
->sgid
),
806 from_kgid_munged(&init_user_ns
, cred
->fsgid
));
807 #ifdef CONFIG_SECURITY
808 printk(KERN_ERR
"CRED: ->security is %p\n", cred
->security
);
809 if ((unsigned long) cred
->security
>= PAGE_SIZE
&&
810 (((unsigned long) cred
->security
& 0xffffff00) !=
811 (POISON_FREE
<< 24 | POISON_FREE
<< 16 | POISON_FREE
<< 8)))
812 printk(KERN_ERR
"CRED: ->security {%x, %x}\n",
813 ((u32
*)cred
->security
)[0],
814 ((u32
*)cred
->security
)[1]);
819 * report use of invalid credentials
821 void __invalid_creds(const struct cred
*cred
, const char *file
, unsigned line
)
823 printk(KERN_ERR
"CRED: Invalid credentials\n");
824 printk(KERN_ERR
"CRED: At %s:%u\n", file
, line
);
825 dump_invalid_creds(cred
, "Specified", current
);
828 EXPORT_SYMBOL(__invalid_creds
);
831 * check the credentials on a process
833 void __validate_process_creds(struct task_struct
*tsk
,
834 const char *file
, unsigned line
)
836 if (tsk
->cred
== tsk
->real_cred
) {
837 if (unlikely(read_cred_subscribers(tsk
->cred
) < 2 ||
838 creds_are_invalid(tsk
->cred
)))
841 if (unlikely(read_cred_subscribers(tsk
->real_cred
) < 1 ||
842 read_cred_subscribers(tsk
->cred
) < 1 ||
843 creds_are_invalid(tsk
->real_cred
) ||
844 creds_are_invalid(tsk
->cred
)))
850 printk(KERN_ERR
"CRED: Invalid process credentials\n");
851 printk(KERN_ERR
"CRED: At %s:%u\n", file
, line
);
853 dump_invalid_creds(tsk
->real_cred
, "Real", tsk
);
854 if (tsk
->cred
!= tsk
->real_cred
)
855 dump_invalid_creds(tsk
->cred
, "Effective", tsk
);
857 printk(KERN_ERR
"CRED: Effective creds == Real creds\n");
860 EXPORT_SYMBOL(__validate_process_creds
);
863 * check creds for do_exit()
865 void validate_creds_for_do_exit(struct task_struct
*tsk
)
867 kdebug("validate_creds_for_do_exit(%p,%p{%d,%d})",
868 tsk
->real_cred
, tsk
->cred
,
869 atomic_read(&tsk
->cred
->usage
),
870 read_cred_subscribers(tsk
->cred
));
872 __validate_process_creds(tsk
, __FILE__
, __LINE__
);
875 #endif /* CONFIG_DEBUG_CREDENTIALS */