2 * This program is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU General Public License as
4 * published by the Free Software Foundation, version 2 of the
8 #include <linux/export.h>
9 #include <linux/nsproxy.h>
10 #include <linux/slab.h>
11 #include <linux/user_namespace.h>
12 #include <linux/proc_ns.h>
13 #include <linux/highuid.h>
14 #include <linux/cred.h>
15 #include <linux/securebits.h>
16 #include <linux/keyctl.h>
17 #include <linux/key-type.h>
18 #include <keys/user-type.h>
19 #include <linux/seq_file.h>
21 #include <linux/uaccess.h>
22 #include <linux/ctype.h>
23 #include <linux/projid.h>
24 #include <linux/fs_struct.h>
26 static struct kmem_cache
*user_ns_cachep __read_mostly
;
28 static bool new_idmap_permitted(const struct file
*file
,
29 struct user_namespace
*ns
, int cap_setid
,
30 struct uid_gid_map
*map
);
32 static void set_cred_user_ns(struct cred
*cred
, struct user_namespace
*user_ns
)
34 /* Start with the same capabilities as init but useless for doing
35 * anything as the capabilities are bound to the new user namespace.
37 cred
->securebits
= SECUREBITS_DEFAULT
;
38 cred
->cap_inheritable
= CAP_EMPTY_SET
;
39 cred
->cap_permitted
= CAP_FULL_SET
;
40 cred
->cap_effective
= CAP_FULL_SET
;
41 cred
->cap_bset
= CAP_FULL_SET
;
43 key_put(cred
->request_key_auth
);
44 cred
->request_key_auth
= NULL
;
46 /* tgcred will be cleared in our caller bc CLONE_THREAD won't be set */
47 cred
->user_ns
= user_ns
;
51 * Create a new user namespace, deriving the creator from the user in the
52 * passed credentials, and replacing that user with the new root user for the
55 * This is called by copy_creds(), which will finish setting the target task's
58 int create_user_ns(struct cred
*new)
60 struct user_namespace
*ns
, *parent_ns
= new->user_ns
;
61 kuid_t owner
= new->euid
;
62 kgid_t group
= new->egid
;
65 if (parent_ns
->level
> 32)
69 * Verify that we can not violate the policy of which files
70 * may be accessed that is specified by the root directory,
71 * by verifing that the root directory is at the root of the
72 * mount namespace which allows all files to be accessed.
74 if (current_chrooted())
77 /* The creator needs a mapping in the parent user namespace
78 * or else we won't be able to reasonably tell userspace who
79 * created a user_namespace.
81 if (!kuid_has_mapping(parent_ns
, owner
) ||
82 !kgid_has_mapping(parent_ns
, group
))
85 ns
= kmem_cache_zalloc(user_ns_cachep
, GFP_KERNEL
);
89 ret
= proc_alloc_inum(&ns
->proc_inum
);
91 kmem_cache_free(user_ns_cachep
, ns
);
95 atomic_set(&ns
->count
, 1);
96 /* Leave the new->user_ns reference with the new user namespace. */
97 ns
->parent
= parent_ns
;
98 ns
->level
= parent_ns
->level
+ 1;
102 set_cred_user_ns(new, ns
);
104 update_mnt_policy(ns
);
109 int unshare_userns(unsigned long unshare_flags
, struct cred
**new_cred
)
114 if (!(unshare_flags
& CLONE_NEWUSER
))
117 cred
= prepare_creds();
119 err
= create_user_ns(cred
);
129 void free_user_ns(struct user_namespace
*ns
)
131 struct user_namespace
*parent
;
135 proc_free_inum(ns
->proc_inum
);
136 kmem_cache_free(user_ns_cachep
, ns
);
138 } while (atomic_dec_and_test(&parent
->count
));
140 EXPORT_SYMBOL(free_user_ns
);
142 static u32
map_id_range_down(struct uid_gid_map
*map
, u32 id
, u32 count
)
144 unsigned idx
, extents
;
145 u32 first
, last
, id2
;
147 id2
= id
+ count
- 1;
149 /* Find the matching extent */
150 extents
= map
->nr_extents
;
151 smp_read_barrier_depends();
152 for (idx
= 0; idx
< extents
; idx
++) {
153 first
= map
->extent
[idx
].first
;
154 last
= first
+ map
->extent
[idx
].count
- 1;
155 if (id
>= first
&& id
<= last
&&
156 (id2
>= first
&& id2
<= last
))
159 /* Map the id or note failure */
161 id
= (id
- first
) + map
->extent
[idx
].lower_first
;
168 static u32
map_id_down(struct uid_gid_map
*map
, u32 id
)
170 unsigned idx
, extents
;
173 /* Find the matching extent */
174 extents
= map
->nr_extents
;
175 smp_read_barrier_depends();
176 for (idx
= 0; idx
< extents
; idx
++) {
177 first
= map
->extent
[idx
].first
;
178 last
= first
+ map
->extent
[idx
].count
- 1;
179 if (id
>= first
&& id
<= last
)
182 /* Map the id or note failure */
184 id
= (id
- first
) + map
->extent
[idx
].lower_first
;
191 static u32
map_id_up(struct uid_gid_map
*map
, u32 id
)
193 unsigned idx
, extents
;
196 /* Find the matching extent */
197 extents
= map
->nr_extents
;
198 smp_read_barrier_depends();
199 for (idx
= 0; idx
< extents
; idx
++) {
200 first
= map
->extent
[idx
].lower_first
;
201 last
= first
+ map
->extent
[idx
].count
- 1;
202 if (id
>= first
&& id
<= last
)
205 /* Map the id or note failure */
207 id
= (id
- first
) + map
->extent
[idx
].first
;
215 * make_kuid - Map a user-namespace uid pair into a kuid.
216 * @ns: User namespace that the uid is in
217 * @uid: User identifier
219 * Maps a user-namespace uid pair into a kernel internal kuid,
220 * and returns that kuid.
222 * When there is no mapping defined for the user-namespace uid
223 * pair INVALID_UID is returned. Callers are expected to test
224 * for and handle handle INVALID_UID being returned. INVALID_UID
225 * may be tested for using uid_valid().
227 kuid_t
make_kuid(struct user_namespace
*ns
, uid_t uid
)
229 /* Map the uid to a global kernel uid */
230 return KUIDT_INIT(map_id_down(&ns
->uid_map
, uid
));
232 EXPORT_SYMBOL(make_kuid
);
235 * from_kuid - Create a uid from a kuid user-namespace pair.
236 * @targ: The user namespace we want a uid in.
237 * @kuid: The kernel internal uid to start with.
239 * Map @kuid into the user-namespace specified by @targ and
240 * return the resulting uid.
242 * There is always a mapping into the initial user_namespace.
244 * If @kuid has no mapping in @targ (uid_t)-1 is returned.
246 uid_t
from_kuid(struct user_namespace
*targ
, kuid_t kuid
)
248 /* Map the uid from a global kernel uid */
249 return map_id_up(&targ
->uid_map
, __kuid_val(kuid
));
251 EXPORT_SYMBOL(from_kuid
);
254 * from_kuid_munged - Create a uid from a kuid user-namespace pair.
255 * @targ: The user namespace we want a uid in.
256 * @kuid: The kernel internal uid to start with.
258 * Map @kuid into the user-namespace specified by @targ and
259 * return the resulting uid.
261 * There is always a mapping into the initial user_namespace.
263 * Unlike from_kuid from_kuid_munged never fails and always
264 * returns a valid uid. This makes from_kuid_munged appropriate
265 * for use in syscalls like stat and getuid where failing the
266 * system call and failing to provide a valid uid are not an
269 * If @kuid has no mapping in @targ overflowuid is returned.
271 uid_t
from_kuid_munged(struct user_namespace
*targ
, kuid_t kuid
)
274 uid
= from_kuid(targ
, kuid
);
276 if (uid
== (uid_t
) -1)
280 EXPORT_SYMBOL(from_kuid_munged
);
283 * make_kgid - Map a user-namespace gid pair into a kgid.
284 * @ns: User namespace that the gid is in
285 * @uid: group identifier
287 * Maps a user-namespace gid pair into a kernel internal kgid,
288 * and returns that kgid.
290 * When there is no mapping defined for the user-namespace gid
291 * pair INVALID_GID is returned. Callers are expected to test
292 * for and handle INVALID_GID being returned. INVALID_GID may be
293 * tested for using gid_valid().
295 kgid_t
make_kgid(struct user_namespace
*ns
, gid_t gid
)
297 /* Map the gid to a global kernel gid */
298 return KGIDT_INIT(map_id_down(&ns
->gid_map
, gid
));
300 EXPORT_SYMBOL(make_kgid
);
303 * from_kgid - Create a gid from a kgid user-namespace pair.
304 * @targ: The user namespace we want a gid in.
305 * @kgid: The kernel internal gid to start with.
307 * Map @kgid into the user-namespace specified by @targ and
308 * return the resulting gid.
310 * There is always a mapping into the initial user_namespace.
312 * If @kgid has no mapping in @targ (gid_t)-1 is returned.
314 gid_t
from_kgid(struct user_namespace
*targ
, kgid_t kgid
)
316 /* Map the gid from a global kernel gid */
317 return map_id_up(&targ
->gid_map
, __kgid_val(kgid
));
319 EXPORT_SYMBOL(from_kgid
);
322 * from_kgid_munged - Create a gid from a kgid user-namespace pair.
323 * @targ: The user namespace we want a gid in.
324 * @kgid: The kernel internal gid to start with.
326 * Map @kgid into the user-namespace specified by @targ and
327 * return the resulting gid.
329 * There is always a mapping into the initial user_namespace.
331 * Unlike from_kgid from_kgid_munged never fails and always
332 * returns a valid gid. This makes from_kgid_munged appropriate
333 * for use in syscalls like stat and getgid where failing the
334 * system call and failing to provide a valid gid are not options.
336 * If @kgid has no mapping in @targ overflowgid is returned.
338 gid_t
from_kgid_munged(struct user_namespace
*targ
, kgid_t kgid
)
341 gid
= from_kgid(targ
, kgid
);
343 if (gid
== (gid_t
) -1)
347 EXPORT_SYMBOL(from_kgid_munged
);
350 * make_kprojid - Map a user-namespace projid pair into a kprojid.
351 * @ns: User namespace that the projid is in
352 * @projid: Project identifier
354 * Maps a user-namespace uid pair into a kernel internal kuid,
355 * and returns that kuid.
357 * When there is no mapping defined for the user-namespace projid
358 * pair INVALID_PROJID is returned. Callers are expected to test
359 * for and handle handle INVALID_PROJID being returned. INVALID_PROJID
360 * may be tested for using projid_valid().
362 kprojid_t
make_kprojid(struct user_namespace
*ns
, projid_t projid
)
364 /* Map the uid to a global kernel uid */
365 return KPROJIDT_INIT(map_id_down(&ns
->projid_map
, projid
));
367 EXPORT_SYMBOL(make_kprojid
);
370 * from_kprojid - Create a projid from a kprojid user-namespace pair.
371 * @targ: The user namespace we want a projid in.
372 * @kprojid: The kernel internal project identifier to start with.
374 * Map @kprojid into the user-namespace specified by @targ and
375 * return the resulting projid.
377 * There is always a mapping into the initial user_namespace.
379 * If @kprojid has no mapping in @targ (projid_t)-1 is returned.
381 projid_t
from_kprojid(struct user_namespace
*targ
, kprojid_t kprojid
)
383 /* Map the uid from a global kernel uid */
384 return map_id_up(&targ
->projid_map
, __kprojid_val(kprojid
));
386 EXPORT_SYMBOL(from_kprojid
);
389 * from_kprojid_munged - Create a projiid from a kprojid user-namespace pair.
390 * @targ: The user namespace we want a projid in.
391 * @kprojid: The kernel internal projid to start with.
393 * Map @kprojid into the user-namespace specified by @targ and
394 * return the resulting projid.
396 * There is always a mapping into the initial user_namespace.
398 * Unlike from_kprojid from_kprojid_munged never fails and always
399 * returns a valid projid. This makes from_kprojid_munged
400 * appropriate for use in syscalls like stat and where
401 * failing the system call and failing to provide a valid projid are
404 * If @kprojid has no mapping in @targ OVERFLOW_PROJID is returned.
406 projid_t
from_kprojid_munged(struct user_namespace
*targ
, kprojid_t kprojid
)
409 projid
= from_kprojid(targ
, kprojid
);
411 if (projid
== (projid_t
) -1)
412 projid
= OVERFLOW_PROJID
;
415 EXPORT_SYMBOL(from_kprojid_munged
);
418 static int uid_m_show(struct seq_file
*seq
, void *v
)
420 struct user_namespace
*ns
= seq
->private;
421 struct uid_gid_extent
*extent
= v
;
422 struct user_namespace
*lower_ns
;
425 lower_ns
= seq_user_ns(seq
);
426 if ((lower_ns
== ns
) && lower_ns
->parent
)
427 lower_ns
= lower_ns
->parent
;
429 lower
= from_kuid(lower_ns
, KUIDT_INIT(extent
->lower_first
));
431 seq_printf(seq
, "%10u %10u %10u\n",
439 static int gid_m_show(struct seq_file
*seq
, void *v
)
441 struct user_namespace
*ns
= seq
->private;
442 struct uid_gid_extent
*extent
= v
;
443 struct user_namespace
*lower_ns
;
446 lower_ns
= seq_user_ns(seq
);
447 if ((lower_ns
== ns
) && lower_ns
->parent
)
448 lower_ns
= lower_ns
->parent
;
450 lower
= from_kgid(lower_ns
, KGIDT_INIT(extent
->lower_first
));
452 seq_printf(seq
, "%10u %10u %10u\n",
460 static int projid_m_show(struct seq_file
*seq
, void *v
)
462 struct user_namespace
*ns
= seq
->private;
463 struct uid_gid_extent
*extent
= v
;
464 struct user_namespace
*lower_ns
;
467 lower_ns
= seq_user_ns(seq
);
468 if ((lower_ns
== ns
) && lower_ns
->parent
)
469 lower_ns
= lower_ns
->parent
;
471 lower
= from_kprojid(lower_ns
, KPROJIDT_INIT(extent
->lower_first
));
473 seq_printf(seq
, "%10u %10u %10u\n",
481 static void *m_start(struct seq_file
*seq
, loff_t
*ppos
, struct uid_gid_map
*map
)
483 struct uid_gid_extent
*extent
= NULL
;
486 if (pos
< map
->nr_extents
)
487 extent
= &map
->extent
[pos
];
492 static void *uid_m_start(struct seq_file
*seq
, loff_t
*ppos
)
494 struct user_namespace
*ns
= seq
->private;
496 return m_start(seq
, ppos
, &ns
->uid_map
);
499 static void *gid_m_start(struct seq_file
*seq
, loff_t
*ppos
)
501 struct user_namespace
*ns
= seq
->private;
503 return m_start(seq
, ppos
, &ns
->gid_map
);
506 static void *projid_m_start(struct seq_file
*seq
, loff_t
*ppos
)
508 struct user_namespace
*ns
= seq
->private;
510 return m_start(seq
, ppos
, &ns
->projid_map
);
513 static void *m_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
516 return seq
->op
->start(seq
, pos
);
519 static void m_stop(struct seq_file
*seq
, void *v
)
524 struct seq_operations proc_uid_seq_operations
= {
525 .start
= uid_m_start
,
531 struct seq_operations proc_gid_seq_operations
= {
532 .start
= gid_m_start
,
538 struct seq_operations proc_projid_seq_operations
= {
539 .start
= projid_m_start
,
542 .show
= projid_m_show
,
545 static bool mappings_overlap(struct uid_gid_map
*new_map
, struct uid_gid_extent
*extent
)
547 u32 upper_first
, lower_first
, upper_last
, lower_last
;
550 upper_first
= extent
->first
;
551 lower_first
= extent
->lower_first
;
552 upper_last
= upper_first
+ extent
->count
- 1;
553 lower_last
= lower_first
+ extent
->count
- 1;
555 for (idx
= 0; idx
< new_map
->nr_extents
; idx
++) {
556 u32 prev_upper_first
, prev_lower_first
;
557 u32 prev_upper_last
, prev_lower_last
;
558 struct uid_gid_extent
*prev
;
560 prev
= &new_map
->extent
[idx
];
562 prev_upper_first
= prev
->first
;
563 prev_lower_first
= prev
->lower_first
;
564 prev_upper_last
= prev_upper_first
+ prev
->count
- 1;
565 prev_lower_last
= prev_lower_first
+ prev
->count
- 1;
567 /* Does the upper range intersect a previous extent? */
568 if ((prev_upper_first
<= upper_last
) &&
569 (prev_upper_last
>= upper_first
))
572 /* Does the lower range intersect a previous extent? */
573 if ((prev_lower_first
<= lower_last
) &&
574 (prev_lower_last
>= lower_first
))
581 static DEFINE_MUTEX(id_map_mutex
);
583 static ssize_t
map_write(struct file
*file
, const char __user
*buf
,
584 size_t count
, loff_t
*ppos
,
586 struct uid_gid_map
*map
,
587 struct uid_gid_map
*parent_map
)
589 struct seq_file
*seq
= file
->private_data
;
590 struct user_namespace
*ns
= seq
->private;
591 struct uid_gid_map new_map
;
593 struct uid_gid_extent
*extent
= NULL
;
594 unsigned long page
= 0;
595 char *kbuf
, *pos
, *next_line
;
596 ssize_t ret
= -EINVAL
;
599 * The id_map_mutex serializes all writes to any given map.
601 * Any map is only ever written once.
603 * An id map fits within 1 cache line on most architectures.
605 * On read nothing needs to be done unless you are on an
606 * architecture with a crazy cache coherency model like alpha.
608 * There is a one time data dependency between reading the
609 * count of the extents and the values of the extents. The
610 * desired behavior is to see the values of the extents that
611 * were written before the count of the extents.
613 * To achieve this smp_wmb() is used on guarantee the write
614 * order and smp_read_barrier_depends() is guaranteed that we
615 * don't have crazy architectures returning stale data.
618 mutex_lock(&id_map_mutex
);
621 /* Only allow one successful write to the map */
622 if (map
->nr_extents
!= 0)
626 * Adjusting namespace settings requires capabilities on the target.
628 if (cap_valid(cap_setid
) && !file_ns_capable(file
, ns
, CAP_SYS_ADMIN
))
633 page
= __get_free_page(GFP_TEMPORARY
);
634 kbuf
= (char *) page
;
638 /* Only allow <= page size writes at the beginning of the file */
640 if ((*ppos
!= 0) || (count
>= PAGE_SIZE
))
643 /* Slurp in the user data */
645 if (copy_from_user(kbuf
, buf
, count
))
649 /* Parse the user data */
652 new_map
.nr_extents
= 0;
653 for (;pos
; pos
= next_line
) {
654 extent
= &new_map
.extent
[new_map
.nr_extents
];
656 /* Find the end of line and ensure I don't look past it */
657 next_line
= strchr(pos
, '\n');
661 if (*next_line
== '\0')
665 pos
= skip_spaces(pos
);
666 extent
->first
= simple_strtoul(pos
, &pos
, 10);
670 pos
= skip_spaces(pos
);
671 extent
->lower_first
= simple_strtoul(pos
, &pos
, 10);
675 pos
= skip_spaces(pos
);
676 extent
->count
= simple_strtoul(pos
, &pos
, 10);
677 if (*pos
&& !isspace(*pos
))
680 /* Verify there is not trailing junk on the line */
681 pos
= skip_spaces(pos
);
685 /* Verify we have been given valid starting values */
686 if ((extent
->first
== (u32
) -1) ||
687 (extent
->lower_first
== (u32
) -1 ))
690 /* Verify count is not zero and does not cause the extent to wrap */
691 if ((extent
->first
+ extent
->count
) <= extent
->first
)
693 if ((extent
->lower_first
+ extent
->count
) <= extent
->lower_first
)
696 /* Do the ranges in extent overlap any previous extents? */
697 if (mappings_overlap(&new_map
, extent
))
700 new_map
.nr_extents
++;
702 /* Fail if the file contains too many extents */
703 if ((new_map
.nr_extents
== UID_GID_MAP_MAX_EXTENTS
) &&
707 /* Be very certaint the new map actually exists */
708 if (new_map
.nr_extents
== 0)
712 /* Validate the user is allowed to use user id's mapped to. */
713 if (!new_idmap_permitted(file
, ns
, cap_setid
, &new_map
))
716 /* Map the lower ids from the parent user namespace to the
717 * kernel global id space.
719 for (idx
= 0; idx
< new_map
.nr_extents
; idx
++) {
721 extent
= &new_map
.extent
[idx
];
723 lower_first
= map_id_range_down(parent_map
,
727 /* Fail if we can not map the specified extent to
728 * the kernel global id space.
730 if (lower_first
== (u32
) -1)
733 extent
->lower_first
= lower_first
;
736 /* Install the map */
737 memcpy(map
->extent
, new_map
.extent
,
738 new_map
.nr_extents
*sizeof(new_map
.extent
[0]));
740 map
->nr_extents
= new_map
.nr_extents
;
745 mutex_unlock(&id_map_mutex
);
751 ssize_t
proc_uid_map_write(struct file
*file
, const char __user
*buf
, size_t size
, loff_t
*ppos
)
753 struct seq_file
*seq
= file
->private_data
;
754 struct user_namespace
*ns
= seq
->private;
755 struct user_namespace
*seq_ns
= seq_user_ns(seq
);
760 if ((seq_ns
!= ns
) && (seq_ns
!= ns
->parent
))
763 return map_write(file
, buf
, size
, ppos
, CAP_SETUID
,
764 &ns
->uid_map
, &ns
->parent
->uid_map
);
767 ssize_t
proc_gid_map_write(struct file
*file
, const char __user
*buf
, size_t size
, loff_t
*ppos
)
769 struct seq_file
*seq
= file
->private_data
;
770 struct user_namespace
*ns
= seq
->private;
771 struct user_namespace
*seq_ns
= seq_user_ns(seq
);
776 if ((seq_ns
!= ns
) && (seq_ns
!= ns
->parent
))
779 return map_write(file
, buf
, size
, ppos
, CAP_SETGID
,
780 &ns
->gid_map
, &ns
->parent
->gid_map
);
783 ssize_t
proc_projid_map_write(struct file
*file
, const char __user
*buf
, size_t size
, loff_t
*ppos
)
785 struct seq_file
*seq
= file
->private_data
;
786 struct user_namespace
*ns
= seq
->private;
787 struct user_namespace
*seq_ns
= seq_user_ns(seq
);
792 if ((seq_ns
!= ns
) && (seq_ns
!= ns
->parent
))
795 /* Anyone can set any valid project id no capability needed */
796 return map_write(file
, buf
, size
, ppos
, -1,
797 &ns
->projid_map
, &ns
->parent
->projid_map
);
800 static bool new_idmap_permitted(const struct file
*file
,
801 struct user_namespace
*ns
, int cap_setid
,
802 struct uid_gid_map
*new_map
)
804 /* Allow mapping to your own filesystem ids */
805 if ((new_map
->nr_extents
== 1) && (new_map
->extent
[0].count
== 1)) {
806 u32 id
= new_map
->extent
[0].lower_first
;
807 if (cap_setid
== CAP_SETUID
) {
808 kuid_t uid
= make_kuid(ns
->parent
, id
);
809 if (uid_eq(uid
, file
->f_cred
->fsuid
))
812 else if (cap_setid
== CAP_SETGID
) {
813 kgid_t gid
= make_kgid(ns
->parent
, id
);
814 if (gid_eq(gid
, file
->f_cred
->fsgid
))
819 /* Allow anyone to set a mapping that doesn't require privilege */
820 if (!cap_valid(cap_setid
))
823 /* Allow the specified ids if we have the appropriate capability
824 * (CAP_SETUID or CAP_SETGID) over the parent user namespace.
825 * And the opener of the id file also had the approprpiate capability.
827 if (ns_capable(ns
->parent
, cap_setid
) &&
828 file_ns_capable(file
, ns
->parent
, cap_setid
))
834 static void *userns_get(struct task_struct
*task
)
836 struct user_namespace
*user_ns
;
839 user_ns
= get_user_ns(__task_cred(task
)->user_ns
);
845 static void userns_put(void *ns
)
850 static int userns_install(struct nsproxy
*nsproxy
, void *ns
)
852 struct user_namespace
*user_ns
= ns
;
855 /* Don't allow gaining capabilities by reentering
856 * the same user namespace.
858 if (user_ns
== current_user_ns())
861 /* Threaded processes may not enter a different user namespace */
862 if (atomic_read(¤t
->mm
->mm_users
) > 1)
865 if (current
->fs
->users
!= 1)
868 if (!ns_capable(user_ns
, CAP_SYS_ADMIN
))
871 cred
= prepare_creds();
875 put_user_ns(cred
->user_ns
);
876 set_cred_user_ns(cred
, get_user_ns(user_ns
));
878 return commit_creds(cred
);
881 static unsigned int userns_inum(void *ns
)
883 struct user_namespace
*user_ns
= ns
;
884 return user_ns
->proc_inum
;
887 const struct proc_ns_operations userns_operations
= {
889 .type
= CLONE_NEWUSER
,
892 .install
= userns_install
,
896 static __init
int user_namespaces_init(void)
898 user_ns_cachep
= KMEM_CACHE(user_namespace
, SLAB_PANIC
);
901 module_init(user_namespaces_init
);