projects/linux·blob v6.4-rc2 · refs

2875 lines · 67.6 KiB

1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/kernel/sys.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 */
7
8#include <linux/export.h>
9#include <linux/mm.h>
10#include <linux/mm_inline.h>
11#include <linux/utsname.h>
12#include <linux/mman.h>
13#include <linux/reboot.h>
14#include <linux/prctl.h>
15#include <linux/highuid.h>
16#include <linux/fs.h>
17#include <linux/kmod.h>
18#include <linux/ksm.h>
19#include <linux/perf_event.h>
20#include <linux/resource.h>
21#include <linux/kernel.h>
22#include <linux/workqueue.h>
23#include <linux/capability.h>
24#include <linux/device.h>
25#include <linux/key.h>
26#include <linux/times.h>
27#include <linux/posix-timers.h>
28#include <linux/security.h>
29#include <linux/random.h>
30#include <linux/suspend.h>
31#include <linux/tty.h>
32#include <linux/signal.h>
33#include <linux/cn_proc.h>
34#include <linux/getcpu.h>
35#include <linux/task_io_accounting_ops.h>
36#include <linux/seccomp.h>
37#include <linux/cpu.h>
38#include <linux/personality.h>
39#include <linux/ptrace.h>
40#include <linux/fs_struct.h>
41#include <linux/file.h>
42#include <linux/mount.h>
43#include <linux/gfp.h>
44#include <linux/syscore_ops.h>
45#include <linux/version.h>
46#include <linux/ctype.h>
47#include <linux/syscall_user_dispatch.h>
48
49#include <linux/compat.h>
50#include <linux/syscalls.h>
51#include <linux/kprobes.h>
52#include <linux/user_namespace.h>
53#include <linux/time_namespace.h>
54#include <linux/binfmts.h>
55
56#include <linux/sched.h>
57#include <linux/sched/autogroup.h>
58#include <linux/sched/loadavg.h>
59#include <linux/sched/stat.h>
60#include <linux/sched/mm.h>
61#include <linux/sched/coredump.h>
62#include <linux/sched/task.h>
63#include <linux/sched/cputime.h>
64#include <linux/rcupdate.h>
65#include <linux/uidgid.h>
66#include <linux/cred.h>
67
68#include <linux/nospec.h>
69
70#include <linux/kmsg_dump.h>
71/* Move somewhere else to avoid recompiling? */
72#include <generated/utsrelease.h>
73
74#include <linux/uaccess.h>
75#include <asm/io.h>
76#include <asm/unistd.h>
77
78#include "uid16.h"
79
80#ifndef SET_UNALIGN_CTL
81# define SET_UNALIGN_CTL(a, b) (-EINVAL)
82#endif
83#ifndef GET_UNALIGN_CTL
84# define GET_UNALIGN_CTL(a, b) (-EINVAL)
85#endif
86#ifndef SET_FPEMU_CTL
87# define SET_FPEMU_CTL(a, b) (-EINVAL)
88#endif
89#ifndef GET_FPEMU_CTL
90# define GET_FPEMU_CTL(a, b) (-EINVAL)
91#endif
92#ifndef SET_FPEXC_CTL
93# define SET_FPEXC_CTL(a, b) (-EINVAL)
94#endif
95#ifndef GET_FPEXC_CTL
96# define GET_FPEXC_CTL(a, b) (-EINVAL)
97#endif
98#ifndef GET_ENDIAN
99# define GET_ENDIAN(a, b) (-EINVAL)
100#endif
101#ifndef SET_ENDIAN
102# define SET_ENDIAN(a, b) (-EINVAL)
103#endif
104#ifndef GET_TSC_CTL
105# define GET_TSC_CTL(a) (-EINVAL)
106#endif
107#ifndef SET_TSC_CTL
108# define SET_TSC_CTL(a) (-EINVAL)
109#endif
110#ifndef GET_FP_MODE
111# define GET_FP_MODE(a) (-EINVAL)
112#endif
113#ifndef SET_FP_MODE
114# define SET_FP_MODE(a,b) (-EINVAL)
115#endif
116#ifndef SVE_SET_VL
117# define SVE_SET_VL(a) (-EINVAL)
118#endif
119#ifndef SVE_GET_VL
120# define SVE_GET_VL() (-EINVAL)
121#endif
122#ifndef SME_SET_VL
123# define SME_SET_VL(a) (-EINVAL)
124#endif
125#ifndef SME_GET_VL
126# define SME_GET_VL() (-EINVAL)
127#endif
128#ifndef PAC_RESET_KEYS
129# define PAC_RESET_KEYS(a, b) (-EINVAL)
130#endif
131#ifndef PAC_SET_ENABLED_KEYS
132# define PAC_SET_ENABLED_KEYS(a, b, c) (-EINVAL)
133#endif
134#ifndef PAC_GET_ENABLED_KEYS
135# define PAC_GET_ENABLED_KEYS(a) (-EINVAL)
136#endif
137#ifndef SET_TAGGED_ADDR_CTRL
138# define SET_TAGGED_ADDR_CTRL(a) (-EINVAL)
139#endif
140#ifndef GET_TAGGED_ADDR_CTRL
141# define GET_TAGGED_ADDR_CTRL() (-EINVAL)
142#endif
143
144/*
145 * this is where the system-wide overflow UID and GID are defined, for
146 * architectures that now have 32-bit UID/GID but didn't in the past
147 */
148
149int overflowuid = DEFAULT_OVERFLOWUID;
150int overflowgid = DEFAULT_OVERFLOWGID;
151
152EXPORT_SYMBOL(overflowuid);
153EXPORT_SYMBOL(overflowgid);
154
155/*
156 * the same as above, but for filesystems which can only store a 16-bit
157 * UID and GID. as such, this is needed on all architectures
158 */
159
160int fs_overflowuid = DEFAULT_FS_OVERFLOWUID;
161int fs_overflowgid = DEFAULT_FS_OVERFLOWGID;
162
163EXPORT_SYMBOL(fs_overflowuid);
164EXPORT_SYMBOL(fs_overflowgid);
165
166/*
167 * Returns true if current's euid is same as p's uid or euid,
168 * or has CAP_SYS_NICE to p's user_ns.
169 *
170 * Called with rcu_read_lock, creds are safe
171 */
172static bool set_one_prio_perm(struct task_struct *p)
173{
174 const struct cred *cred = current_cred(), *pcred = __task_cred(p);
175
176 if (uid_eq(pcred->uid, cred->euid) ||
177 uid_eq(pcred->euid, cred->euid))
178 return true;
179 if (ns_capable(pcred->user_ns, CAP_SYS_NICE))
180 return true;
181 return false;
182}
183
184/*
185 * set the priority of a task
186 * - the caller must hold the RCU read lock
187 */
188static int set_one_prio(struct task_struct *p, int niceval, int error)
189{
190 int no_nice;
191
192 if (!set_one_prio_perm(p)) {
193 error = -EPERM;
194 goto out;
195 }
196 if (niceval < task_nice(p) && !can_nice(p, niceval)) {
197 error = -EACCES;
198 goto out;
199 }
200 no_nice = security_task_setnice(p, niceval);
201 if (no_nice) {
202 error = no_nice;
203 goto out;
204 }
205 if (error == -ESRCH)
206 error = 0;
207 set_user_nice(p, niceval);
208out:
209 return error;
210}
211
212SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
213{
214 struct task_struct *g, *p;
215 struct user_struct *user;
216 const struct cred *cred = current_cred();
217 int error = -EINVAL;
218 struct pid *pgrp;
219 kuid_t uid;
220
221 if (which > PRIO_USER || which < PRIO_PROCESS)
222 goto out;
223
224 /* normalize: avoid signed division (rounding problems) */
225 error = -ESRCH;
226 if (niceval < MIN_NICE)
227 niceval = MIN_NICE;
228 if (niceval > MAX_NICE)
229 niceval = MAX_NICE;
230
231 rcu_read_lock();
232 switch (which) {
233 case PRIO_PROCESS:
234 if (who)
235 p = find_task_by_vpid(who);
236 else
237 p = current;
238 if (p)
239 error = set_one_prio(p, niceval, error);
240 break;
241 case PRIO_PGRP:
242 if (who)
243 pgrp = find_vpid(who);
244 else
245 pgrp = task_pgrp(current);
246 read_lock(&tasklist_lock);
247 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
248 error = set_one_prio(p, niceval, error);
249 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
250 read_unlock(&tasklist_lock);
251 break;
252 case PRIO_USER:
253 uid = make_kuid(cred->user_ns, who);
254 user = cred->user;
255 if (!who)
256 uid = cred->uid;
257 else if (!uid_eq(uid, cred->uid)) {
258 user = find_user(uid);
259 if (!user)
260 goto out_unlock; /* No processes for this user */
261 }
262 for_each_process_thread(g, p) {
263 if (uid_eq(task_uid(p), uid) && task_pid_vnr(p))
264 error = set_one_prio(p, niceval, error);
265 }
266 if (!uid_eq(uid, cred->uid))
267 free_uid(user); /* For find_user() */
268 break;
269 }
270out_unlock:
271 rcu_read_unlock();
272out:
273 return error;
274}
275
276/*
277 * Ugh. To avoid negative return values, "getpriority()" will
278 * not return the normal nice-value, but a negated value that
279 * has been offset by 20 (ie it returns 40..1 instead of -20..19)
280 * to stay compatible.
281 */
282SYSCALL_DEFINE2(getpriority, int, which, int, who)
283{
284 struct task_struct *g, *p;
285 struct user_struct *user;
286 const struct cred *cred = current_cred();
287 long niceval, retval = -ESRCH;
288 struct pid *pgrp;
289 kuid_t uid;
290
291 if (which > PRIO_USER || which < PRIO_PROCESS)
292 return -EINVAL;
293
294 rcu_read_lock();
295 switch (which) {
296 case PRIO_PROCESS:
297 if (who)
298 p = find_task_by_vpid(who);
299 else
300 p = current;
301 if (p) {
302 niceval = nice_to_rlimit(task_nice(p));
303 if (niceval > retval)
304 retval = niceval;
305 }
306 break;
307 case PRIO_PGRP:
308 if (who)
309 pgrp = find_vpid(who);
310 else
311 pgrp = task_pgrp(current);
312 read_lock(&tasklist_lock);
313 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
314 niceval = nice_to_rlimit(task_nice(p));
315 if (niceval > retval)
316 retval = niceval;
317 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
318 read_unlock(&tasklist_lock);
319 break;
320 case PRIO_USER:
321 uid = make_kuid(cred->user_ns, who);
322 user = cred->user;
323 if (!who)
324 uid = cred->uid;
325 else if (!uid_eq(uid, cred->uid)) {
326 user = find_user(uid);
327 if (!user)
328 goto out_unlock; /* No processes for this user */
329 }
330 for_each_process_thread(g, p) {
331 if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) {
332 niceval = nice_to_rlimit(task_nice(p));
333 if (niceval > retval)
334 retval = niceval;
335 }
336 }
337 if (!uid_eq(uid, cred->uid))
338 free_uid(user); /* for find_user() */
339 break;
340 }
341out_unlock:
342 rcu_read_unlock();
343
344 return retval;
345}
346
347/*
348 * Unprivileged users may change the real gid to the effective gid
349 * or vice versa. (BSD-style)
350 *
351 * If you set the real gid at all, or set the effective gid to a value not
352 * equal to the real gid, then the saved gid is set to the new effective gid.
353 *
354 * This makes it possible for a setgid program to completely drop its
355 * privileges, which is often a useful assertion to make when you are doing
356 * a security audit over a program.
357 *
358 * The general idea is that a program which uses just setregid() will be
359 * 100% compatible with BSD. A program which uses just setgid() will be
360 * 100% compatible with POSIX with saved IDs.
361 *
362 * SMP: There are not races, the GIDs are checked only by filesystem
363 * operations (as far as semantic preservation is concerned).
364 */
365#ifdef CONFIG_MULTIUSER
366long __sys_setregid(gid_t rgid, gid_t egid)
367{
368 struct user_namespace *ns = current_user_ns();
369 const struct cred *old;
370 struct cred *new;
371 int retval;
372 kgid_t krgid, kegid;
373
374 krgid = make_kgid(ns, rgid);
375 kegid = make_kgid(ns, egid);
376
377 if ((rgid != (gid_t) -1) && !gid_valid(krgid))
378 return -EINVAL;
379 if ((egid != (gid_t) -1) && !gid_valid(kegid))
380 return -EINVAL;
381
382 new = prepare_creds();
383 if (!new)
384 return -ENOMEM;
385 old = current_cred();
386
387 retval = -EPERM;
388 if (rgid != (gid_t) -1) {
389 if (gid_eq(old->gid, krgid) ||
390 gid_eq(old->egid, krgid) ||
391 ns_capable_setid(old->user_ns, CAP_SETGID))
392 new->gid = krgid;
393 else
394 goto error;
395 }
396 if (egid != (gid_t) -1) {
397 if (gid_eq(old->gid, kegid) ||
398 gid_eq(old->egid, kegid) ||
399 gid_eq(old->sgid, kegid) ||
400 ns_capable_setid(old->user_ns, CAP_SETGID))
401 new->egid = kegid;
402 else
403 goto error;
404 }
405
406 if (rgid != (gid_t) -1 ||
407 (egid != (gid_t) -1 && !gid_eq(kegid, old->gid)))
408 new->sgid = new->egid;
409 new->fsgid = new->egid;
410
411 retval = security_task_fix_setgid(new, old, LSM_SETID_RE);
412 if (retval < 0)
413 goto error;
414
415 return commit_creds(new);
416
417error:
418 abort_creds(new);
419 return retval;
420}
421
422SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
423{
424 return __sys_setregid(rgid, egid);
425}
426
427/*
428 * setgid() is implemented like SysV w/ SAVED_IDS
429 *
430 * SMP: Same implicit races as above.
431 */
432long __sys_setgid(gid_t gid)
433{
434 struct user_namespace *ns = current_user_ns();
435 const struct cred *old;
436 struct cred *new;
437 int retval;
438 kgid_t kgid;
439
440 kgid = make_kgid(ns, gid);
441 if (!gid_valid(kgid))
442 return -EINVAL;
443
444 new = prepare_creds();
445 if (!new)
446 return -ENOMEM;
447 old = current_cred();
448
449 retval = -EPERM;
450 if (ns_capable_setid(old->user_ns, CAP_SETGID))
451 new->gid = new->egid = new->sgid = new->fsgid = kgid;
452 else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid))
453 new->egid = new->fsgid = kgid;
454 else
455 goto error;
456
457 retval = security_task_fix_setgid(new, old, LSM_SETID_ID);
458 if (retval < 0)
459 goto error;
460
461 return commit_creds(new);
462
463error:
464 abort_creds(new);
465 return retval;
466}
467
468SYSCALL_DEFINE1(setgid, gid_t, gid)
469{
470 return __sys_setgid(gid);
471}
472
473/*
474 * change the user struct in a credentials set to match the new UID
475 */
476static int set_user(struct cred *new)
477{
478 struct user_struct *new_user;
479
480 new_user = alloc_uid(new->uid);
481 if (!new_user)
482 return -EAGAIN;
483
484 free_uid(new->user);
485 new->user = new_user;
486 return 0;
487}
488
489static void flag_nproc_exceeded(struct cred *new)
490{
491 if (new->ucounts == current_ucounts())
492 return;
493
494 /*
495 * We don't fail in case of NPROC limit excess here because too many
496 * poorly written programs don't check set*uid() return code, assuming
497 * it never fails if called by root. We may still enforce NPROC limit
498 * for programs doing set*uid()+execve() by harmlessly deferring the
499 * failure to the execve() stage.
500 */
501 if (is_rlimit_overlimit(new->ucounts, UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC)) &&
502 new->user != INIT_USER)
503 current->flags |= PF_NPROC_EXCEEDED;
504 else
505 current->flags &= ~PF_NPROC_EXCEEDED;
506}
507
508/*
509 * Unprivileged users may change the real uid to the effective uid
510 * or vice versa. (BSD-style)
511 *
512 * If you set the real uid at all, or set the effective uid to a value not
513 * equal to the real uid, then the saved uid is set to the new effective uid.
514 *
515 * This makes it possible for a setuid program to completely drop its
516 * privileges, which is often a useful assertion to make when you are doing
517 * a security audit over a program.
518 *
519 * The general idea is that a program which uses just setreuid() will be
520 * 100% compatible with BSD. A program which uses just setuid() will be
521 * 100% compatible with POSIX with saved IDs.
522 */
523long __sys_setreuid(uid_t ruid, uid_t euid)
524{
525 struct user_namespace *ns = current_user_ns();
526 const struct cred *old;
527 struct cred *new;
528 int retval;
529 kuid_t kruid, keuid;
530
531 kruid = make_kuid(ns, ruid);
532 keuid = make_kuid(ns, euid);
533
534 if ((ruid != (uid_t) -1) && !uid_valid(kruid))
535 return -EINVAL;
536 if ((euid != (uid_t) -1) && !uid_valid(keuid))
537 return -EINVAL;
538
539 new = prepare_creds();
540 if (!new)
541 return -ENOMEM;
542 old = current_cred();
543
544 retval = -EPERM;
545 if (ruid != (uid_t) -1) {
546 new->uid = kruid;
547 if (!uid_eq(old->uid, kruid) &&
548 !uid_eq(old->euid, kruid) &&
549 !ns_capable_setid(old->user_ns, CAP_SETUID))
550 goto error;
551 }
552
553 if (euid != (uid_t) -1) {
554 new->euid = keuid;
555 if (!uid_eq(old->uid, keuid) &&
556 !uid_eq(old->euid, keuid) &&
557 !uid_eq(old->suid, keuid) &&
558 !ns_capable_setid(old->user_ns, CAP_SETUID))
559 goto error;
560 }
561
562 if (!uid_eq(new->uid, old->uid)) {
563 retval = set_user(new);
564 if (retval < 0)
565 goto error;
566 }
567 if (ruid != (uid_t) -1 ||
568 (euid != (uid_t) -1 && !uid_eq(keuid, old->uid)))
569 new->suid = new->euid;
570 new->fsuid = new->euid;
571
572 retval = security_task_fix_setuid(new, old, LSM_SETID_RE);
573 if (retval < 0)
574 goto error;
575
576 retval = set_cred_ucounts(new);
577 if (retval < 0)
578 goto error;
579
580 flag_nproc_exceeded(new);
581 return commit_creds(new);
582
583error:
584 abort_creds(new);
585 return retval;
586}
587
588SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
589{
590 return __sys_setreuid(ruid, euid);
591}
592
593/*
594 * setuid() is implemented like SysV with SAVED_IDS
595 *
596 * Note that SAVED_ID's is deficient in that a setuid root program
597 * like sendmail, for example, cannot set its uid to be a normal
598 * user and then switch back, because if you're root, setuid() sets
599 * the saved uid too. If you don't like this, blame the bright people
600 * in the POSIX committee and/or USG. Note that the BSD-style setreuid()
601 * will allow a root program to temporarily drop privileges and be able to
602 * regain them by swapping the real and effective uid.
603 */
604long __sys_setuid(uid_t uid)
605{
606 struct user_namespace *ns = current_user_ns();
607 const struct cred *old;
608 struct cred *new;
609 int retval;
610 kuid_t kuid;
611
612 kuid = make_kuid(ns, uid);
613 if (!uid_valid(kuid))
614 return -EINVAL;
615
616 new = prepare_creds();
617 if (!new)
618 return -ENOMEM;
619 old = current_cred();
620
621 retval = -EPERM;
622 if (ns_capable_setid(old->user_ns, CAP_SETUID)) {
623 new->suid = new->uid = kuid;
624 if (!uid_eq(kuid, old->uid)) {
625 retval = set_user(new);
626 if (retval < 0)
627 goto error;
628 }
629 } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) {
630 goto error;
631 }
632
633 new->fsuid = new->euid = kuid;
634
635 retval = security_task_fix_setuid(new, old, LSM_SETID_ID);
636 if (retval < 0)
637 goto error;
638
639 retval = set_cred_ucounts(new);
640 if (retval < 0)
641 goto error;
642
643 flag_nproc_exceeded(new);
644 return commit_creds(new);
645
646error:
647 abort_creds(new);
648 return retval;
649}
650
651SYSCALL_DEFINE1(setuid, uid_t, uid)
652{
653 return __sys_setuid(uid);
654}
655
656
657/*
658 * This function implements a generic ability to update ruid, euid,
659 * and suid. This allows you to implement the 4.4 compatible seteuid().
660 */
661long __sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
662{
663 struct user_namespace *ns = current_user_ns();
664 const struct cred *old;
665 struct cred *new;
666 int retval;
667 kuid_t kruid, keuid, ksuid;
668 bool ruid_new, euid_new, suid_new;
669
670 kruid = make_kuid(ns, ruid);
671 keuid = make_kuid(ns, euid);
672 ksuid = make_kuid(ns, suid);
673
674 if ((ruid != (uid_t) -1) && !uid_valid(kruid))
675 return -EINVAL;
676
677 if ((euid != (uid_t) -1) && !uid_valid(keuid))
678 return -EINVAL;
679
680 if ((suid != (uid_t) -1) && !uid_valid(ksuid))
681 return -EINVAL;
682
683 old = current_cred();
684
685 /* check for no-op */
686 if ((ruid == (uid_t) -1 || uid_eq(kruid, old->uid)) &&
687 (euid == (uid_t) -1 || (uid_eq(keuid, old->euid) &&
688 uid_eq(keuid, old->fsuid))) &&
689 (suid == (uid_t) -1 || uid_eq(ksuid, old->suid)))
690 return 0;
691
692 ruid_new = ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) &&
693 !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid);
694 euid_new = euid != (uid_t) -1 && !uid_eq(keuid, old->uid) &&
695 !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid);
696 suid_new = suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) &&
697 !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid);
698 if ((ruid_new || euid_new || suid_new) &&
699 !ns_capable_setid(old->user_ns, CAP_SETUID))
700 return -EPERM;
701
702 new = prepare_creds();
703 if (!new)
704 return -ENOMEM;
705
706 if (ruid != (uid_t) -1) {
707 new->uid = kruid;
708 if (!uid_eq(kruid, old->uid)) {
709 retval = set_user(new);
710 if (retval < 0)
711 goto error;
712 }
713 }
714 if (euid != (uid_t) -1)
715 new->euid = keuid;
716 if (suid != (uid_t) -1)
717 new->suid = ksuid;
718 new->fsuid = new->euid;
719
720 retval = security_task_fix_setuid(new, old, LSM_SETID_RES);
721 if (retval < 0)
722 goto error;
723
724 retval = set_cred_ucounts(new);
725 if (retval < 0)
726 goto error;
727
728 flag_nproc_exceeded(new);
729 return commit_creds(new);
730
731error:
732 abort_creds(new);
733 return retval;
734}
735
736SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid)
737{
738 return __sys_setresuid(ruid, euid, suid);
739}
740
741SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp)
742{
743 const struct cred *cred = current_cred();
744 int retval;
745 uid_t ruid, euid, suid;
746
747 ruid = from_kuid_munged(cred->user_ns, cred->uid);
748 euid = from_kuid_munged(cred->user_ns, cred->euid);
749 suid = from_kuid_munged(cred->user_ns, cred->suid);
750
751 retval = put_user(ruid, ruidp);
752 if (!retval) {
753 retval = put_user(euid, euidp);
754 if (!retval)
755 return put_user(suid, suidp);
756 }
757 return retval;
758}
759
760/*
761 * Same as above, but for rgid, egid, sgid.
762 */
763long __sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
764{
765 struct user_namespace *ns = current_user_ns();
766 const struct cred *old;
767 struct cred *new;
768 int retval;
769 kgid_t krgid, kegid, ksgid;
770 bool rgid_new, egid_new, sgid_new;
771
772 krgid = make_kgid(ns, rgid);
773 kegid = make_kgid(ns, egid);
774 ksgid = make_kgid(ns, sgid);
775
776 if ((rgid != (gid_t) -1) && !gid_valid(krgid))
777 return -EINVAL;
778 if ((egid != (gid_t) -1) && !gid_valid(kegid))
779 return -EINVAL;
780 if ((sgid != (gid_t) -1) && !gid_valid(ksgid))
781 return -EINVAL;
782
783 old = current_cred();
784
785 /* check for no-op */
786 if ((rgid == (gid_t) -1 || gid_eq(krgid, old->gid)) &&
787 (egid == (gid_t) -1 || (gid_eq(kegid, old->egid) &&
788 gid_eq(kegid, old->fsgid))) &&
789 (sgid == (gid_t) -1 || gid_eq(ksgid, old->sgid)))
790 return 0;
791
792 rgid_new = rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) &&
793 !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid);
794 egid_new = egid != (gid_t) -1 && !gid_eq(kegid, old->gid) &&
795 !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid);
796 sgid_new = sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) &&
797 !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid);
798 if ((rgid_new || egid_new || sgid_new) &&
799 !ns_capable_setid(old->user_ns, CAP_SETGID))
800 return -EPERM;
801
802 new = prepare_creds();
803 if (!new)
804 return -ENOMEM;
805
806 if (rgid != (gid_t) -1)
807 new->gid = krgid;
808 if (egid != (gid_t) -1)
809 new->egid = kegid;
810 if (sgid != (gid_t) -1)
811 new->sgid = ksgid;
812 new->fsgid = new->egid;
813
814 retval = security_task_fix_setgid(new, old, LSM_SETID_RES);
815 if (retval < 0)
816 goto error;
817
818 return commit_creds(new);
819
820error:
821 abort_creds(new);
822 return retval;
823}
824
825SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid)
826{
827 return __sys_setresgid(rgid, egid, sgid);
828}
829
830SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp)
831{
832 const struct cred *cred = current_cred();
833 int retval;
834 gid_t rgid, egid, sgid;
835
836 rgid = from_kgid_munged(cred->user_ns, cred->gid);
837 egid = from_kgid_munged(cred->user_ns, cred->egid);
838 sgid = from_kgid_munged(cred->user_ns, cred->sgid);
839
840 retval = put_user(rgid, rgidp);
841 if (!retval) {
842 retval = put_user(egid, egidp);
843 if (!retval)
844 retval = put_user(sgid, sgidp);
845 }
846
847 return retval;
848}
849
850
851/*
852 * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This
853 * is used for "access()" and for the NFS daemon (letting nfsd stay at
854 * whatever uid it wants to). It normally shadows "euid", except when
855 * explicitly set by setfsuid() or for access..
856 */
857long __sys_setfsuid(uid_t uid)
858{
859 const struct cred *old;
860 struct cred *new;
861 uid_t old_fsuid;
862 kuid_t kuid;
863
864 old = current_cred();
865 old_fsuid = from_kuid_munged(old->user_ns, old->fsuid);
866
867 kuid = make_kuid(old->user_ns, uid);
868 if (!uid_valid(kuid))
869 return old_fsuid;
870
871 new = prepare_creds();
872 if (!new)
873 return old_fsuid;
874
875 if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) ||
876 uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) ||
877 ns_capable_setid(old->user_ns, CAP_SETUID)) {
878 if (!uid_eq(kuid, old->fsuid)) {
879 new->fsuid = kuid;
880 if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0)
881 goto change_okay;
882 }
883 }
884
885 abort_creds(new);
886 return old_fsuid;
887
888change_okay:
889 commit_creds(new);
890 return old_fsuid;
891}
892
893SYSCALL_DEFINE1(setfsuid, uid_t, uid)
894{
895 return __sys_setfsuid(uid);
896}
897
898/*
899 * Samma på svenska..
900 */
901long __sys_setfsgid(gid_t gid)
902{
903 const struct cred *old;
904 struct cred *new;
905 gid_t old_fsgid;
906 kgid_t kgid;
907
908 old = current_cred();
909 old_fsgid = from_kgid_munged(old->user_ns, old->fsgid);
910
911 kgid = make_kgid(old->user_ns, gid);
912 if (!gid_valid(kgid))
913 return old_fsgid;
914
915 new = prepare_creds();
916 if (!new)
917 return old_fsgid;
918
919 if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) ||
920 gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) ||
921 ns_capable_setid(old->user_ns, CAP_SETGID)) {
922 if (!gid_eq(kgid, old->fsgid)) {
923 new->fsgid = kgid;
924 if (security_task_fix_setgid(new,old,LSM_SETID_FS) == 0)
925 goto change_okay;
926 }
927 }
928
929 abort_creds(new);
930 return old_fsgid;
931
932change_okay:
933 commit_creds(new);
934 return old_fsgid;
935}
936
937SYSCALL_DEFINE1(setfsgid, gid_t, gid)
938{
939 return __sys_setfsgid(gid);
940}
941#endif /* CONFIG_MULTIUSER */
942
943/**
944 * sys_getpid - return the thread group id of the current process
945 *
946 * Note, despite the name, this returns the tgid not the pid. The tgid and
947 * the pid are identical unless CLONE_THREAD was specified on clone() in
948 * which case the tgid is the same in all threads of the same group.
949 *
950 * This is SMP safe as current->tgid does not change.
951 */
952SYSCALL_DEFINE0(getpid)
953{
954 return task_tgid_vnr(current);
955}
956
957/* Thread ID - the internal kernel "pid" */
958SYSCALL_DEFINE0(gettid)
959{
960 return task_pid_vnr(current);
961}
962
963/*
964 * Accessing ->real_parent is not SMP-safe, it could
965 * change from under us. However, we can use a stale
966 * value of ->real_parent under rcu_read_lock(), see
967 * release_task()->call_rcu(delayed_put_task_struct).
968 */
969SYSCALL_DEFINE0(getppid)
970{
971 int pid;
972
973 rcu_read_lock();
974 pid = task_tgid_vnr(rcu_dereference(current->real_parent));
975 rcu_read_unlock();
976
977 return pid;
978}
979
980SYSCALL_DEFINE0(getuid)
981{
982 /* Only we change this so SMP safe */
983 return from_kuid_munged(current_user_ns(), current_uid());
984}
985
986SYSCALL_DEFINE0(geteuid)
987{
988 /* Only we change this so SMP safe */
989 return from_kuid_munged(current_user_ns(), current_euid());
990}
991
992SYSCALL_DEFINE0(getgid)
993{
994 /* Only we change this so SMP safe */
995 return from_kgid_munged(current_user_ns(), current_gid());
996}
997
998SYSCALL_DEFINE0(getegid)
999{
1000 /* Only we change this so SMP safe */
1001 return from_kgid_munged(current_user_ns(), current_egid());
1002}
1003
1004static void do_sys_times(struct tms *tms)
1005{
1006 u64 tgutime, tgstime, cutime, cstime;
1007
1008 thread_group_cputime_adjusted(current, &tgutime, &tgstime);
1009 cutime = current->signal->cutime;
1010 cstime = current->signal->cstime;
1011 tms->tms_utime = nsec_to_clock_t(tgutime);
1012 tms->tms_stime = nsec_to_clock_t(tgstime);
1013 tms->tms_cutime = nsec_to_clock_t(cutime);
1014 tms->tms_cstime = nsec_to_clock_t(cstime);
1015}
1016
1017SYSCALL_DEFINE1(times, struct tms __user *, tbuf)
1018{
1019 if (tbuf) {
1020 struct tms tmp;
1021
1022 do_sys_times(&tmp);
1023 if (copy_to_user(tbuf, &tmp, sizeof(struct tms)))
1024 return -EFAULT;
1025 }
1026 force_successful_syscall_return();
1027 return (long) jiffies_64_to_clock_t(get_jiffies_64());
1028}
1029
1030#ifdef CONFIG_COMPAT
1031static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
1032{
1033 return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
1034}
1035
1036COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
1037{
1038 if (tbuf) {
1039 struct tms tms;
1040 struct compat_tms tmp;
1041
1042 do_sys_times(&tms);
1043 /* Convert our struct tms to the compat version. */
1044 tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
1045 tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
1046 tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
1047 tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
1048 if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
1049 return -EFAULT;
1050 }
1051 force_successful_syscall_return();
1052 return compat_jiffies_to_clock_t(jiffies);
1053}
1054#endif
1055
1056/*
1057 * This needs some heavy checking ...
1058 * I just haven't the stomach for it. I also don't fully
1059 * understand sessions/pgrp etc. Let somebody who does explain it.
1060 *
1061 * OK, I think I have the protection semantics right.... this is really
1062 * only important on a multi-user system anyway, to make sure one user
1063 * can't send a signal to a process owned by another. -TYT, 12/12/91
1064 *
1065 * !PF_FORKNOEXEC check to conform completely to POSIX.
1066 */
1067SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid)
1068{
1069 struct task_struct *p;
1070 struct task_struct *group_leader = current->group_leader;
1071 struct pid *pgrp;
1072 int err;
1073
1074 if (!pid)
1075 pid = task_pid_vnr(group_leader);
1076 if (!pgid)
1077 pgid = pid;
1078 if (pgid < 0)
1079 return -EINVAL;
1080 rcu_read_lock();
1081
1082 /* From this point forward we keep holding onto the tasklist lock
1083 * so that our parent does not change from under us. -DaveM
1084 */
1085 write_lock_irq(&tasklist_lock);
1086
1087 err = -ESRCH;
1088 p = find_task_by_vpid(pid);
1089 if (!p)
1090 goto out;
1091
1092 err = -EINVAL;
1093 if (!thread_group_leader(p))
1094 goto out;
1095
1096 if (same_thread_group(p->real_parent, group_leader)) {
1097 err = -EPERM;
1098 if (task_session(p) != task_session(group_leader))
1099 goto out;
1100 err = -EACCES;
1101 if (!(p->flags & PF_FORKNOEXEC))
1102 goto out;
1103 } else {
1104 err = -ESRCH;
1105 if (p != group_leader)
1106 goto out;
1107 }
1108
1109 err = -EPERM;
1110 if (p->signal->leader)
1111 goto out;
1112
1113 pgrp = task_pid(p);
1114 if (pgid != pid) {
1115 struct task_struct *g;
1116
1117 pgrp = find_vpid(pgid);
1118 g = pid_task(pgrp, PIDTYPE_PGID);
1119 if (!g || task_session(g) != task_session(group_leader))
1120 goto out;
1121 }
1122
1123 err = security_task_setpgid(p, pgid);
1124 if (err)
1125 goto out;
1126
1127 if (task_pgrp(p) != pgrp)
1128 change_pid(p, PIDTYPE_PGID, pgrp);
1129
1130 err = 0;
1131out:
1132 /* All paths lead to here, thus we are safe. -DaveM */
1133 write_unlock_irq(&tasklist_lock);
1134 rcu_read_unlock();
1135 return err;
1136}
1137
1138static int do_getpgid(pid_t pid)
1139{
1140 struct task_struct *p;
1141 struct pid *grp;
1142 int retval;
1143
1144 rcu_read_lock();
1145 if (!pid)
1146 grp = task_pgrp(current);
1147 else {
1148 retval = -ESRCH;
1149 p = find_task_by_vpid(pid);
1150 if (!p)
1151 goto out;
1152 grp = task_pgrp(p);
1153 if (!grp)
1154 goto out;
1155
1156 retval = security_task_getpgid(p);
1157 if (retval)
1158 goto out;
1159 }
1160 retval = pid_vnr(grp);
1161out:
1162 rcu_read_unlock();
1163 return retval;
1164}
1165
1166SYSCALL_DEFINE1(getpgid, pid_t, pid)
1167{
1168 return do_getpgid(pid);
1169}
1170
1171#ifdef __ARCH_WANT_SYS_GETPGRP
1172
1173SYSCALL_DEFINE0(getpgrp)
1174{
1175 return do_getpgid(0);
1176}
1177
1178#endif
1179
1180SYSCALL_DEFINE1(getsid, pid_t, pid)
1181{
1182 struct task_struct *p;
1183 struct pid *sid;
1184 int retval;
1185
1186 rcu_read_lock();
1187 if (!pid)
1188 sid = task_session(current);
1189 else {
1190 retval = -ESRCH;
1191 p = find_task_by_vpid(pid);
1192 if (!p)
1193 goto out;
1194 sid = task_session(p);
1195 if (!sid)
1196 goto out;
1197
1198 retval = security_task_getsid(p);
1199 if (retval)
1200 goto out;
1201 }
1202 retval = pid_vnr(sid);
1203out:
1204 rcu_read_unlock();
1205 return retval;
1206}
1207
1208static void set_special_pids(struct pid *pid)
1209{
1210 struct task_struct *curr = current->group_leader;
1211
1212 if (task_session(curr) != pid)
1213 change_pid(curr, PIDTYPE_SID, pid);
1214
1215 if (task_pgrp(curr) != pid)
1216 change_pid(curr, PIDTYPE_PGID, pid);
1217}
1218
1219int ksys_setsid(void)
1220{
1221 struct task_struct *group_leader = current->group_leader;
1222 struct pid *sid = task_pid(group_leader);
1223 pid_t session = pid_vnr(sid);
1224 int err = -EPERM;
1225
1226 write_lock_irq(&tasklist_lock);
1227 /* Fail if I am already a session leader */
1228 if (group_leader->signal->leader)
1229 goto out;
1230
1231 /* Fail if a process group id already exists that equals the
1232 * proposed session id.
1233 */
1234 if (pid_task(sid, PIDTYPE_PGID))
1235 goto out;
1236
1237 group_leader->signal->leader = 1;
1238 set_special_pids(sid);
1239
1240 proc_clear_tty(group_leader);
1241
1242 err = session;
1243out:
1244 write_unlock_irq(&tasklist_lock);
1245 if (err > 0) {
1246 proc_sid_connector(group_leader);
1247 sched_autogroup_create_attach(group_leader);
1248 }
1249 return err;
1250}
1251
1252SYSCALL_DEFINE0(setsid)
1253{
1254 return ksys_setsid();
1255}
1256
1257DECLARE_RWSEM(uts_sem);
1258
1259#ifdef COMPAT_UTS_MACHINE
1260#define override_architecture(name) \
1261 (personality(current->personality) == PER_LINUX32 && \
1262 copy_to_user(name->machine, COMPAT_UTS_MACHINE, \
1263 sizeof(COMPAT_UTS_MACHINE)))
1264#else
1265#define override_architecture(name) 0
1266#endif
1267
1268/*
1269 * Work around broken programs that cannot handle "Linux 3.0".
1270 * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
1271 * And we map 4.x and later versions to 2.6.60+x, so 4.0/5.0/6.0/... would be
1272 * 2.6.60.
1273 */
1274static int override_release(char __user *release, size_t len)
1275{
1276 int ret = 0;
1277
1278 if (current->personality & UNAME26) {
1279 const char *rest = UTS_RELEASE;
1280 char buf[65] = { 0 };
1281 int ndots = 0;
1282 unsigned v;
1283 size_t copy;
1284
1285 while (*rest) {
1286 if (*rest == '.' && ++ndots >= 3)
1287 break;
1288 if (!isdigit(*rest) && *rest != '.')
1289 break;
1290 rest++;
1291 }
1292 v = LINUX_VERSION_PATCHLEVEL + 60;
1293 copy = clamp_t(size_t, len, 1, sizeof(buf));
1294 copy = scnprintf(buf, copy, "2.6.%u%s", v, rest);
1295 ret = copy_to_user(release, buf, copy + 1);
1296 }
1297 return ret;
1298}
1299
1300SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
1301{
1302 struct new_utsname tmp;
1303
1304 down_read(&uts_sem);
1305 memcpy(&tmp, utsname(), sizeof(tmp));
1306 up_read(&uts_sem);
1307 if (copy_to_user(name, &tmp, sizeof(tmp)))
1308 return -EFAULT;
1309
1310 if (override_release(name->release, sizeof(name->release)))
1311 return -EFAULT;
1312 if (override_architecture(name))
1313 return -EFAULT;
1314 return 0;
1315}
1316
1317#ifdef __ARCH_WANT_SYS_OLD_UNAME
1318/*
1319 * Old cruft
1320 */
1321SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
1322{
1323 struct old_utsname tmp;
1324
1325 if (!name)
1326 return -EFAULT;
1327
1328 down_read(&uts_sem);
1329 memcpy(&tmp, utsname(), sizeof(tmp));
1330 up_read(&uts_sem);
1331 if (copy_to_user(name, &tmp, sizeof(tmp)))
1332 return -EFAULT;
1333
1334 if (override_release(name->release, sizeof(name->release)))
1335 return -EFAULT;
1336 if (override_architecture(name))
1337 return -EFAULT;
1338 return 0;
1339}
1340
1341SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
1342{
1343 struct oldold_utsname tmp;
1344
1345 if (!name)
1346 return -EFAULT;
1347
1348 memset(&tmp, 0, sizeof(tmp));
1349
1350 down_read(&uts_sem);
1351 memcpy(&tmp.sysname, &utsname()->sysname, __OLD_UTS_LEN);
1352 memcpy(&tmp.nodename, &utsname()->nodename, __OLD_UTS_LEN);
1353 memcpy(&tmp.release, &utsname()->release, __OLD_UTS_LEN);
1354 memcpy(&tmp.version, &utsname()->version, __OLD_UTS_LEN);
1355 memcpy(&tmp.machine, &utsname()->machine, __OLD_UTS_LEN);
1356 up_read(&uts_sem);
1357 if (copy_to_user(name, &tmp, sizeof(tmp)))
1358 return -EFAULT;
1359
1360 if (override_architecture(name))
1361 return -EFAULT;
1362 if (override_release(name->release, sizeof(name->release)))
1363 return -EFAULT;
1364 return 0;
1365}
1366#endif
1367
1368SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
1369{
1370 int errno;
1371 char tmp[__NEW_UTS_LEN];
1372
1373 if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1374 return -EPERM;
1375
1376 if (len < 0 || len > __NEW_UTS_LEN)
1377 return -EINVAL;
1378 errno = -EFAULT;
1379 if (!copy_from_user(tmp, name, len)) {
1380 struct new_utsname *u;
1381
1382 add_device_randomness(tmp, len);
1383 down_write(&uts_sem);
1384 u = utsname();
1385 memcpy(u->nodename, tmp, len);
1386 memset(u->nodename + len, 0, sizeof(u->nodename) - len);
1387 errno = 0;
1388 uts_proc_notify(UTS_PROC_HOSTNAME);
1389 up_write(&uts_sem);
1390 }
1391 return errno;
1392}
1393
1394#ifdef __ARCH_WANT_SYS_GETHOSTNAME
1395
1396SYSCALL_DEFINE2(gethostname, char __user *, name, int, len)
1397{
1398 int i;
1399 struct new_utsname *u;
1400 char tmp[__NEW_UTS_LEN + 1];
1401
1402 if (len < 0)
1403 return -EINVAL;
1404 down_read(&uts_sem);
1405 u = utsname();
1406 i = 1 + strlen(u->nodename);
1407 if (i > len)
1408 i = len;
1409 memcpy(tmp, u->nodename, i);
1410 up_read(&uts_sem);
1411 if (copy_to_user(name, tmp, i))
1412 return -EFAULT;
1413 return 0;
1414}
1415
1416#endif
1417
1418/*
1419 * Only setdomainname; getdomainname can be implemented by calling
1420 * uname()
1421 */
1422SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len)
1423{
1424 int errno;
1425 char tmp[__NEW_UTS_LEN];
1426
1427 if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1428 return -EPERM;
1429 if (len < 0 || len > __NEW_UTS_LEN)
1430 return -EINVAL;
1431
1432 errno = -EFAULT;
1433 if (!copy_from_user(tmp, name, len)) {
1434 struct new_utsname *u;
1435
1436 add_device_randomness(tmp, len);
1437 down_write(&uts_sem);
1438 u = utsname();
1439 memcpy(u->domainname, tmp, len);
1440 memset(u->domainname + len, 0, sizeof(u->domainname) - len);
1441 errno = 0;
1442 uts_proc_notify(UTS_PROC_DOMAINNAME);
1443 up_write(&uts_sem);
1444 }
1445 return errno;
1446}
1447
1448/* make sure you are allowed to change @tsk limits before calling this */
1449static int do_prlimit(struct task_struct *tsk, unsigned int resource,
1450 struct rlimit *new_rlim, struct rlimit *old_rlim)
1451{
1452 struct rlimit *rlim;
1453 int retval = 0;
1454
1455 if (resource >= RLIM_NLIMITS)
1456 return -EINVAL;
1457 resource = array_index_nospec(resource, RLIM_NLIMITS);
1458
1459 if (new_rlim) {
1460 if (new_rlim->rlim_cur > new_rlim->rlim_max)
1461 return -EINVAL;
1462 if (resource == RLIMIT_NOFILE &&
1463 new_rlim->rlim_max > sysctl_nr_open)
1464 return -EPERM;
1465 }
1466
1467 /* Holding a refcount on tsk protects tsk->signal from disappearing. */
1468 rlim = tsk->signal->rlim + resource;
1469 task_lock(tsk->group_leader);
1470 if (new_rlim) {
1471 /*
1472 * Keep the capable check against init_user_ns until cgroups can
1473 * contain all limits.
1474 */
1475 if (new_rlim->rlim_max > rlim->rlim_max &&
1476 !capable(CAP_SYS_RESOURCE))
1477 retval = -EPERM;
1478 if (!retval)
1479 retval = security_task_setrlimit(tsk, resource, new_rlim);
1480 }
1481 if (!retval) {
1482 if (old_rlim)
1483 *old_rlim = *rlim;
1484 if (new_rlim)
1485 *rlim = *new_rlim;
1486 }
1487 task_unlock(tsk->group_leader);
1488
1489 /*
1490 * RLIMIT_CPU handling. Arm the posix CPU timer if the limit is not
1491 * infinite. In case of RLIM_INFINITY the posix CPU timer code
1492 * ignores the rlimit.
1493 */
1494 if (!retval && new_rlim && resource == RLIMIT_CPU &&
1495 new_rlim->rlim_cur != RLIM_INFINITY &&
1496 IS_ENABLED(CONFIG_POSIX_TIMERS)) {
1497 /*
1498 * update_rlimit_cpu can fail if the task is exiting, but there
1499 * may be other tasks in the thread group that are not exiting,
1500 * and they need their cpu timers adjusted.
1501 *
1502 * The group_leader is the last task to be released, so if we
1503 * cannot update_rlimit_cpu on it, then the entire process is
1504 * exiting and we do not need to update at all.
1505 */
1506 update_rlimit_cpu(tsk->group_leader, new_rlim->rlim_cur);
1507 }
1508
1509 return retval;
1510}
1511
1512SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1513{
1514 struct rlimit value;
1515 int ret;
1516
1517 ret = do_prlimit(current, resource, NULL, &value);
1518 if (!ret)
1519 ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0;
1520
1521 return ret;
1522}
1523
1524#ifdef CONFIG_COMPAT
1525
1526COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
1527 struct compat_rlimit __user *, rlim)
1528{
1529 struct rlimit r;
1530 struct compat_rlimit r32;
1531
1532 if (copy_from_user(&r32, rlim, sizeof(struct compat_rlimit)))
1533 return -EFAULT;
1534
1535 if (r32.rlim_cur == COMPAT_RLIM_INFINITY)
1536 r.rlim_cur = RLIM_INFINITY;
1537 else
1538 r.rlim_cur = r32.rlim_cur;
1539 if (r32.rlim_max == COMPAT_RLIM_INFINITY)
1540 r.rlim_max = RLIM_INFINITY;
1541 else
1542 r.rlim_max = r32.rlim_max;
1543 return do_prlimit(current, resource, &r, NULL);
1544}
1545
1546COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
1547 struct compat_rlimit __user *, rlim)
1548{
1549 struct rlimit r;
1550 int ret;
1551
1552 ret = do_prlimit(current, resource, NULL, &r);
1553 if (!ret) {
1554 struct compat_rlimit r32;
1555 if (r.rlim_cur > COMPAT_RLIM_INFINITY)
1556 r32.rlim_cur = COMPAT_RLIM_INFINITY;
1557 else
1558 r32.rlim_cur = r.rlim_cur;
1559 if (r.rlim_max > COMPAT_RLIM_INFINITY)
1560 r32.rlim_max = COMPAT_RLIM_INFINITY;
1561 else
1562 r32.rlim_max = r.rlim_max;
1563
1564 if (copy_to_user(rlim, &r32, sizeof(struct compat_rlimit)))
1565 return -EFAULT;
1566 }
1567 return ret;
1568}
1569
1570#endif
1571
1572#ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
1573
1574/*
1575 * Back compatibility for getrlimit. Needed for some apps.
1576 */
1577SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1578 struct rlimit __user *, rlim)
1579{
1580 struct rlimit x;
1581 if (resource >= RLIM_NLIMITS)
1582 return -EINVAL;
1583
1584 resource = array_index_nospec(resource, RLIM_NLIMITS);
1585 task_lock(current->group_leader);
1586 x = current->signal->rlim[resource];
1587 task_unlock(current->group_leader);
1588 if (x.rlim_cur > 0x7FFFFFFF)
1589 x.rlim_cur = 0x7FFFFFFF;
1590 if (x.rlim_max > 0x7FFFFFFF)
1591 x.rlim_max = 0x7FFFFFFF;
1592 return copy_to_user(rlim, &x, sizeof(x)) ? -EFAULT : 0;
1593}
1594
1595#ifdef CONFIG_COMPAT
1596COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1597 struct compat_rlimit __user *, rlim)
1598{
1599 struct rlimit r;
1600
1601 if (resource >= RLIM_NLIMITS)
1602 return -EINVAL;
1603
1604 resource = array_index_nospec(resource, RLIM_NLIMITS);
1605 task_lock(current->group_leader);
1606 r = current->signal->rlim[resource];
1607 task_unlock(current->group_leader);
1608 if (r.rlim_cur > 0x7FFFFFFF)
1609 r.rlim_cur = 0x7FFFFFFF;
1610 if (r.rlim_max > 0x7FFFFFFF)
1611 r.rlim_max = 0x7FFFFFFF;
1612
1613 if (put_user(r.rlim_cur, &rlim->rlim_cur) ||
1614 put_user(r.rlim_max, &rlim->rlim_max))
1615 return -EFAULT;
1616 return 0;
1617}
1618#endif
1619
1620#endif
1621
1622static inline bool rlim64_is_infinity(__u64 rlim64)
1623{
1624#if BITS_PER_LONG < 64
1625 return rlim64 >= ULONG_MAX;
1626#else
1627 return rlim64 == RLIM64_INFINITY;
1628#endif
1629}
1630
1631static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64)
1632{
1633 if (rlim->rlim_cur == RLIM_INFINITY)
1634 rlim64->rlim_cur = RLIM64_INFINITY;
1635 else
1636 rlim64->rlim_cur = rlim->rlim_cur;
1637 if (rlim->rlim_max == RLIM_INFINITY)
1638 rlim64->rlim_max = RLIM64_INFINITY;
1639 else
1640 rlim64->rlim_max = rlim->rlim_max;
1641}
1642
1643static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim)
1644{
1645 if (rlim64_is_infinity(rlim64->rlim_cur))
1646 rlim->rlim_cur = RLIM_INFINITY;
1647 else
1648 rlim->rlim_cur = (unsigned long)rlim64->rlim_cur;
1649 if (rlim64_is_infinity(rlim64->rlim_max))
1650 rlim->rlim_max = RLIM_INFINITY;
1651 else
1652 rlim->rlim_max = (unsigned long)rlim64->rlim_max;
1653}
1654
1655/* rcu lock must be held */
1656static int check_prlimit_permission(struct task_struct *task,
1657 unsigned int flags)
1658{
1659 const struct cred *cred = current_cred(), *tcred;
1660 bool id_match;
1661
1662 if (current == task)
1663 return 0;
1664
1665 tcred = __task_cred(task);
1666 id_match = (uid_eq(cred->uid, tcred->euid) &&
1667 uid_eq(cred->uid, tcred->suid) &&
1668 uid_eq(cred->uid, tcred->uid) &&
1669 gid_eq(cred->gid, tcred->egid) &&
1670 gid_eq(cred->gid, tcred->sgid) &&
1671 gid_eq(cred->gid, tcred->gid));
1672 if (!id_match && !ns_capable(tcred->user_ns, CAP_SYS_RESOURCE))
1673 return -EPERM;
1674
1675 return security_task_prlimit(cred, tcred, flags);
1676}
1677
1678SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource,
1679 const struct rlimit64 __user *, new_rlim,
1680 struct rlimit64 __user *, old_rlim)
1681{
1682 struct rlimit64 old64, new64;
1683 struct rlimit old, new;
1684 struct task_struct *tsk;
1685 unsigned int checkflags = 0;
1686 int ret;
1687
1688 if (old_rlim)
1689 checkflags |= LSM_PRLIMIT_READ;
1690
1691 if (new_rlim) {
1692 if (copy_from_user(&new64, new_rlim, sizeof(new64)))
1693 return -EFAULT;
1694 rlim64_to_rlim(&new64, &new);
1695 checkflags |= LSM_PRLIMIT_WRITE;
1696 }
1697
1698 rcu_read_lock();
1699 tsk = pid ? find_task_by_vpid(pid) : current;
1700 if (!tsk) {
1701 rcu_read_unlock();
1702 return -ESRCH;
1703 }
1704 ret = check_prlimit_permission(tsk, checkflags);
1705 if (ret) {
1706 rcu_read_unlock();
1707 return ret;
1708 }
1709 get_task_struct(tsk);
1710 rcu_read_unlock();
1711
1712 ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL,
1713 old_rlim ? &old : NULL);
1714
1715 if (!ret && old_rlim) {
1716 rlim_to_rlim64(&old, &old64);
1717 if (copy_to_user(old_rlim, &old64, sizeof(old64)))
1718 ret = -EFAULT;
1719 }
1720
1721 put_task_struct(tsk);
1722 return ret;
1723}
1724
1725SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1726{
1727 struct rlimit new_rlim;
1728
1729 if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
1730 return -EFAULT;
1731 return do_prlimit(current, resource, &new_rlim, NULL);
1732}
1733
1734/*
1735 * It would make sense to put struct rusage in the task_struct,
1736 * except that would make the task_struct be *really big*. After
1737 * task_struct gets moved into malloc'ed memory, it would
1738 * make sense to do this. It will make moving the rest of the information
1739 * a lot simpler! (Which we're not doing right now because we're not
1740 * measuring them yet).
1741 *
1742 * When sampling multiple threads for RUSAGE_SELF, under SMP we might have
1743 * races with threads incrementing their own counters. But since word
1744 * reads are atomic, we either get new values or old values and we don't
1745 * care which for the sums. We always take the siglock to protect reading
1746 * the c* fields from p->signal from races with exit.c updating those
1747 * fields when reaping, so a sample either gets all the additions of a
1748 * given child after it's reaped, or none so this sample is before reaping.
1749 *
1750 * Locking:
1751 * We need to take the siglock for CHILDEREN, SELF and BOTH
1752 * for the cases current multithreaded, non-current single threaded
1753 * non-current multithreaded. Thread traversal is now safe with
1754 * the siglock held.
1755 * Strictly speaking, we donot need to take the siglock if we are current and
1756 * single threaded, as no one else can take our signal_struct away, no one
1757 * else can reap the children to update signal->c* counters, and no one else
1758 * can race with the signal-> fields. If we do not take any lock, the
1759 * signal-> fields could be read out of order while another thread was just
1760 * exiting. So we should place a read memory barrier when we avoid the lock.
1761 * On the writer side, write memory barrier is implied in __exit_signal
1762 * as __exit_signal releases the siglock spinlock after updating the signal->
1763 * fields. But we don't do this yet to keep things simple.
1764 *
1765 */
1766
1767static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r)
1768{
1769 r->ru_nvcsw += t->nvcsw;
1770 r->ru_nivcsw += t->nivcsw;
1771 r->ru_minflt += t->min_flt;
1772 r->ru_majflt += t->maj_flt;
1773 r->ru_inblock += task_io_get_inblock(t);
1774 r->ru_oublock += task_io_get_oublock(t);
1775}
1776
1777void getrusage(struct task_struct *p, int who, struct rusage *r)
1778{
1779 struct task_struct *t;
1780 unsigned long flags;
1781 u64 tgutime, tgstime, utime, stime;
1782 unsigned long maxrss = 0;
1783
1784 memset((char *)r, 0, sizeof (*r));
1785 utime = stime = 0;
1786
1787 if (who == RUSAGE_THREAD) {
1788 task_cputime_adjusted(current, &utime, &stime);
1789 accumulate_thread_rusage(p, r);
1790 maxrss = p->signal->maxrss;
1791 goto out;
1792 }
1793
1794 if (!lock_task_sighand(p, &flags))
1795 return;
1796
1797 switch (who) {
1798 case RUSAGE_BOTH:
1799 case RUSAGE_CHILDREN:
1800 utime = p->signal->cutime;
1801 stime = p->signal->cstime;
1802 r->ru_nvcsw = p->signal->cnvcsw;
1803 r->ru_nivcsw = p->signal->cnivcsw;
1804 r->ru_minflt = p->signal->cmin_flt;
1805 r->ru_majflt = p->signal->cmaj_flt;
1806 r->ru_inblock = p->signal->cinblock;
1807 r->ru_oublock = p->signal->coublock;
1808 maxrss = p->signal->cmaxrss;
1809
1810 if (who == RUSAGE_CHILDREN)
1811 break;
1812 fallthrough;
1813
1814 case RUSAGE_SELF:
1815 thread_group_cputime_adjusted(p, &tgutime, &tgstime);
1816 utime += tgutime;
1817 stime += tgstime;
1818 r->ru_nvcsw += p->signal->nvcsw;
1819 r->ru_nivcsw += p->signal->nivcsw;
1820 r->ru_minflt += p->signal->min_flt;
1821 r->ru_majflt += p->signal->maj_flt;
1822 r->ru_inblock += p->signal->inblock;
1823 r->ru_oublock += p->signal->oublock;
1824 if (maxrss < p->signal->maxrss)
1825 maxrss = p->signal->maxrss;
1826 t = p;
1827 do {
1828 accumulate_thread_rusage(t, r);
1829 } while_each_thread(p, t);
1830 break;
1831
1832 default:
1833 BUG();
1834 }
1835 unlock_task_sighand(p, &flags);
1836
1837out:
1838 r->ru_utime = ns_to_kernel_old_timeval(utime);
1839 r->ru_stime = ns_to_kernel_old_timeval(stime);
1840
1841 if (who != RUSAGE_CHILDREN) {
1842 struct mm_struct *mm = get_task_mm(p);
1843
1844 if (mm) {
1845 setmax_mm_hiwater_rss(&maxrss, mm);
1846 mmput(mm);
1847 }
1848 }
1849 r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */
1850}
1851
1852SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru)
1853{
1854 struct rusage r;
1855
1856 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1857 who != RUSAGE_THREAD)
1858 return -EINVAL;
1859
1860 getrusage(current, who, &r);
1861 return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
1862}
1863
1864#ifdef CONFIG_COMPAT
1865COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru)
1866{
1867 struct rusage r;
1868
1869 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1870 who != RUSAGE_THREAD)
1871 return -EINVAL;
1872
1873 getrusage(current, who, &r);
1874 return put_compat_rusage(&r, ru);
1875}
1876#endif
1877
1878SYSCALL_DEFINE1(umask, int, mask)
1879{
1880 mask = xchg(&current->fs->umask, mask & S_IRWXUGO);
1881 return mask;
1882}
1883
1884static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
1885{
1886 struct fd exe;
1887 struct inode *inode;
1888 int err;
1889
1890 exe = fdget(fd);
1891 if (!exe.file)
1892 return -EBADF;
1893
1894 inode = file_inode(exe.file);
1895
1896 /*
1897 * Because the original mm->exe_file points to executable file, make
1898 * sure that this one is executable as well, to avoid breaking an
1899 * overall picture.
1900 */
1901 err = -EACCES;
1902 if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path))
1903 goto exit;
1904
1905 err = file_permission(exe.file, MAY_EXEC);
1906 if (err)
1907 goto exit;
1908
1909 err = replace_mm_exe_file(mm, exe.file);
1910exit:
1911 fdput(exe);
1912 return err;
1913}
1914
1915/*
1916 * Check arithmetic relations of passed addresses.
1917 *
1918 * WARNING: we don't require any capability here so be very careful
1919 * in what is allowed for modification from userspace.
1920 */
1921static int validate_prctl_map_addr(struct prctl_mm_map *prctl_map)
1922{
1923 unsigned long mmap_max_addr = TASK_SIZE;
1924 int error = -EINVAL, i;
1925
1926 static const unsigned char offsets[] = {
1927 offsetof(struct prctl_mm_map, start_code),
1928 offsetof(struct prctl_mm_map, end_code),
1929 offsetof(struct prctl_mm_map, start_data),
1930 offsetof(struct prctl_mm_map, end_data),
1931 offsetof(struct prctl_mm_map, start_brk),
1932 offsetof(struct prctl_mm_map, brk),
1933 offsetof(struct prctl_mm_map, start_stack),
1934 offsetof(struct prctl_mm_map, arg_start),
1935 offsetof(struct prctl_mm_map, arg_end),
1936 offsetof(struct prctl_mm_map, env_start),
1937 offsetof(struct prctl_mm_map, env_end),
1938 };
1939
1940 /*
1941 * Make sure the members are not somewhere outside
1942 * of allowed address space.
1943 */
1944 for (i = 0; i < ARRAY_SIZE(offsets); i++) {
1945 u64 val = *(u64 *)((char *)prctl_map + offsets[i]);
1946
1947 if ((unsigned long)val >= mmap_max_addr ||
1948 (unsigned long)val < mmap_min_addr)
1949 goto out;
1950 }
1951
1952 /*
1953 * Make sure the pairs are ordered.
1954 */
1955#define __prctl_check_order(__m1, __op, __m2) \
1956 ((unsigned long)prctl_map->__m1 __op \
1957 (unsigned long)prctl_map->__m2) ? 0 : -EINVAL
1958 error = __prctl_check_order(start_code, <, end_code);
1959 error |= __prctl_check_order(start_data,<=, end_data);
1960 error |= __prctl_check_order(start_brk, <=, brk);
1961 error |= __prctl_check_order(arg_start, <=, arg_end);
1962 error |= __prctl_check_order(env_start, <=, env_end);
1963 if (error)
1964 goto out;
1965#undef __prctl_check_order
1966
1967 error = -EINVAL;
1968
1969 /*
1970 * Neither we should allow to override limits if they set.
1971 */
1972 if (check_data_rlimit(rlimit(RLIMIT_DATA), prctl_map->brk,
1973 prctl_map->start_brk, prctl_map->end_data,
1974 prctl_map->start_data))
1975 goto out;
1976
1977 error = 0;
1978out:
1979 return error;
1980}
1981
1982#ifdef CONFIG_CHECKPOINT_RESTORE
1983static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size)
1984{
1985 struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, };
1986 unsigned long user_auxv[AT_VECTOR_SIZE];
1987 struct mm_struct *mm = current->mm;
1988 int error;
1989
1990 BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
1991 BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256);
1992
1993 if (opt == PR_SET_MM_MAP_SIZE)
1994 return put_user((unsigned int)sizeof(prctl_map),
1995 (unsigned int __user *)addr);
1996
1997 if (data_size != sizeof(prctl_map))
1998 return -EINVAL;
1999
2000 if (copy_from_user(&prctl_map, addr, sizeof(prctl_map)))
2001 return -EFAULT;
2002
2003 error = validate_prctl_map_addr(&prctl_map);
2004 if (error)
2005 return error;
2006
2007 if (prctl_map.auxv_size) {
2008 /*
2009 * Someone is trying to cheat the auxv vector.
2010 */
2011 if (!prctl_map.auxv ||
2012 prctl_map.auxv_size > sizeof(mm->saved_auxv))
2013 return -EINVAL;
2014
2015 memset(user_auxv, 0, sizeof(user_auxv));
2016 if (copy_from_user(user_auxv,
2017 (const void __user *)prctl_map.auxv,
2018 prctl_map.auxv_size))
2019 return -EFAULT;
2020
2021 /* Last entry must be AT_NULL as specification requires */
2022 user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL;
2023 user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL;
2024 }
2025
2026 if (prctl_map.exe_fd != (u32)-1) {
2027 /*
2028 * Check if the current user is checkpoint/restore capable.
2029 * At the time of this writing, it checks for CAP_SYS_ADMIN
2030 * or CAP_CHECKPOINT_RESTORE.
2031 * Note that a user with access to ptrace can masquerade an
2032 * arbitrary program as any executable, even setuid ones.
2033 * This may have implications in the tomoyo subsystem.
2034 */
2035 if (!checkpoint_restore_ns_capable(current_user_ns()))
2036 return -EPERM;
2037
2038 error = prctl_set_mm_exe_file(mm, prctl_map.exe_fd);
2039 if (error)
2040 return error;
2041 }
2042
2043 /*
2044 * arg_lock protects concurrent updates but we still need mmap_lock for
2045 * read to exclude races with sys_brk.
2046 */
2047 mmap_read_lock(mm);
2048
2049 /*
2050 * We don't validate if these members are pointing to
2051 * real present VMAs because application may have correspond
2052 * VMAs already unmapped and kernel uses these members for statistics
2053 * output in procfs mostly, except
2054 *
2055 * - @start_brk/@brk which are used in do_brk_flags but kernel lookups
2056 * for VMAs when updating these members so anything wrong written
2057 * here cause kernel to swear at userspace program but won't lead
2058 * to any problem in kernel itself
2059 */
2060
2061 spin_lock(&mm->arg_lock);
2062 mm->start_code = prctl_map.start_code;
2063 mm->end_code = prctl_map.end_code;
2064 mm->start_data = prctl_map.start_data;
2065 mm->end_data = prctl_map.end_data;
2066 mm->start_brk = prctl_map.start_brk;
2067 mm->brk = prctl_map.brk;
2068 mm->start_stack = prctl_map.start_stack;
2069 mm->arg_start = prctl_map.arg_start;
2070 mm->arg_end = prctl_map.arg_end;
2071 mm->env_start = prctl_map.env_start;
2072 mm->env_end = prctl_map.env_end;
2073 spin_unlock(&mm->arg_lock);
2074
2075 /*
2076 * Note this update of @saved_auxv is lockless thus
2077 * if someone reads this member in procfs while we're
2078 * updating -- it may get partly updated results. It's
2079 * known and acceptable trade off: we leave it as is to
2080 * not introduce additional locks here making the kernel
2081 * more complex.
2082 */
2083 if (prctl_map.auxv_size)
2084 memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv));
2085
2086 mmap_read_unlock(mm);
2087 return 0;
2088}
2089#endif /* CONFIG_CHECKPOINT_RESTORE */
2090
2091static int prctl_set_auxv(struct mm_struct *mm, unsigned long addr,
2092 unsigned long len)
2093{
2094 /*
2095 * This doesn't move the auxiliary vector itself since it's pinned to
2096 * mm_struct, but it permits filling the vector with new values. It's
2097 * up to the caller to provide sane values here, otherwise userspace
2098 * tools which use this vector might be unhappy.
2099 */
2100 unsigned long user_auxv[AT_VECTOR_SIZE] = {};
2101
2102 if (len > sizeof(user_auxv))
2103 return -EINVAL;
2104
2105 if (copy_from_user(user_auxv, (const void __user *)addr, len))
2106 return -EFAULT;
2107
2108 /* Make sure the last entry is always AT_NULL */
2109 user_auxv[AT_VECTOR_SIZE - 2] = 0;
2110 user_auxv[AT_VECTOR_SIZE - 1] = 0;
2111
2112 BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
2113
2114 task_lock(current);
2115 memcpy(mm->saved_auxv, user_auxv, len);
2116 task_unlock(current);
2117
2118 return 0;
2119}
2120
2121static int prctl_set_mm(int opt, unsigned long addr,
2122 unsigned long arg4, unsigned long arg5)
2123{
2124 struct mm_struct *mm = current->mm;
2125 struct prctl_mm_map prctl_map = {
2126 .auxv = NULL,
2127 .auxv_size = 0,
2128 .exe_fd = -1,
2129 };
2130 struct vm_area_struct *vma;
2131 int error;
2132
2133 if (arg5 || (arg4 && (opt != PR_SET_MM_AUXV &&
2134 opt != PR_SET_MM_MAP &&
2135 opt != PR_SET_MM_MAP_SIZE)))
2136 return -EINVAL;
2137
2138#ifdef CONFIG_CHECKPOINT_RESTORE
2139 if (opt == PR_SET_MM_MAP || opt == PR_SET_MM_MAP_SIZE)
2140 return prctl_set_mm_map(opt, (const void __user *)addr, arg4);
2141#endif
2142
2143 if (!capable(CAP_SYS_RESOURCE))
2144 return -EPERM;
2145
2146 if (opt == PR_SET_MM_EXE_FILE)
2147 return prctl_set_mm_exe_file(mm, (unsigned int)addr);
2148
2149 if (opt == PR_SET_MM_AUXV)
2150 return prctl_set_auxv(mm, addr, arg4);
2151
2152 if (addr >= TASK_SIZE || addr < mmap_min_addr)
2153 return -EINVAL;
2154
2155 error = -EINVAL;
2156
2157 /*
2158 * arg_lock protects concurrent updates of arg boundaries, we need
2159 * mmap_lock for a) concurrent sys_brk, b) finding VMA for addr
2160 * validation.
2161 */
2162 mmap_read_lock(mm);
2163 vma = find_vma(mm, addr);
2164
2165 spin_lock(&mm->arg_lock);
2166 prctl_map.start_code = mm->start_code;
2167 prctl_map.end_code = mm->end_code;
2168 prctl_map.start_data = mm->start_data;
2169 prctl_map.end_data = mm->end_data;
2170 prctl_map.start_brk = mm->start_brk;
2171 prctl_map.brk = mm->brk;
2172 prctl_map.start_stack = mm->start_stack;
2173 prctl_map.arg_start = mm->arg_start;
2174 prctl_map.arg_end = mm->arg_end;
2175 prctl_map.env_start = mm->env_start;
2176 prctl_map.env_end = mm->env_end;
2177
2178 switch (opt) {
2179 case PR_SET_MM_START_CODE:
2180 prctl_map.start_code = addr;
2181 break;
2182 case PR_SET_MM_END_CODE:
2183 prctl_map.end_code = addr;
2184 break;
2185 case PR_SET_MM_START_DATA:
2186 prctl_map.start_data = addr;
2187 break;
2188 case PR_SET_MM_END_DATA:
2189 prctl_map.end_data = addr;
2190 break;
2191 case PR_SET_MM_START_STACK:
2192 prctl_map.start_stack = addr;
2193 break;
2194 case PR_SET_MM_START_BRK:
2195 prctl_map.start_brk = addr;
2196 break;
2197 case PR_SET_MM_BRK:
2198 prctl_map.brk = addr;
2199 break;
2200 case PR_SET_MM_ARG_START:
2201 prctl_map.arg_start = addr;
2202 break;
2203 case PR_SET_MM_ARG_END:
2204 prctl_map.arg_end = addr;
2205 break;
2206 case PR_SET_MM_ENV_START:
2207 prctl_map.env_start = addr;
2208 break;
2209 case PR_SET_MM_ENV_END:
2210 prctl_map.env_end = addr;
2211 break;
2212 default:
2213 goto out;
2214 }
2215
2216 error = validate_prctl_map_addr(&prctl_map);
2217 if (error)
2218 goto out;
2219
2220 switch (opt) {
2221 /*
2222 * If command line arguments and environment
2223 * are placed somewhere else on stack, we can
2224 * set them up here, ARG_START/END to setup
2225 * command line arguments and ENV_START/END
2226 * for environment.
2227 */
2228 case PR_SET_MM_START_STACK:
2229 case PR_SET_MM_ARG_START:
2230 case PR_SET_MM_ARG_END:
2231 case PR_SET_MM_ENV_START:
2232 case PR_SET_MM_ENV_END:
2233 if (!vma) {
2234 error = -EFAULT;
2235 goto out;
2236 }
2237 }
2238
2239 mm->start_code = prctl_map.start_code;
2240 mm->end_code = prctl_map.end_code;
2241 mm->start_data = prctl_map.start_data;
2242 mm->end_data = prctl_map.end_data;
2243 mm->start_brk = prctl_map.start_brk;
2244 mm->brk = prctl_map.brk;
2245 mm->start_stack = prctl_map.start_stack;
2246 mm->arg_start = prctl_map.arg_start;
2247 mm->arg_end = prctl_map.arg_end;
2248 mm->env_start = prctl_map.env_start;
2249 mm->env_end = prctl_map.env_end;
2250
2251 error = 0;
2252out:
2253 spin_unlock(&mm->arg_lock);
2254 mmap_read_unlock(mm);
2255 return error;
2256}
2257
2258#ifdef CONFIG_CHECKPOINT_RESTORE
2259static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr)
2260{
2261 return put_user(me->clear_child_tid, tid_addr);
2262}
2263#else
2264static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr)
2265{
2266 return -EINVAL;
2267}
2268#endif
2269
2270static int propagate_has_child_subreaper(struct task_struct *p, void *data)
2271{
2272 /*
2273 * If task has has_child_subreaper - all its descendants
2274 * already have these flag too and new descendants will
2275 * inherit it on fork, skip them.
2276 *
2277 * If we've found child_reaper - skip descendants in
2278 * it's subtree as they will never get out pidns.
2279 */
2280 if (p->signal->has_child_subreaper ||
2281 is_child_reaper(task_pid(p)))
2282 return 0;
2283
2284 p->signal->has_child_subreaper = 1;
2285 return 1;
2286}
2287
2288int __weak arch_prctl_spec_ctrl_get(struct task_struct *t, unsigned long which)
2289{
2290 return -EINVAL;
2291}
2292
2293int __weak arch_prctl_spec_ctrl_set(struct task_struct *t, unsigned long which,
2294 unsigned long ctrl)
2295{
2296 return -EINVAL;
2297}
2298
2299#define PR_IO_FLUSHER (PF_MEMALLOC_NOIO | PF_LOCAL_THROTTLE)
2300
2301#ifdef CONFIG_ANON_VMA_NAME
2302
2303#define ANON_VMA_NAME_MAX_LEN 80
2304#define ANON_VMA_NAME_INVALID_CHARS "\\`$[]"
2305
2306static inline bool is_valid_name_char(char ch)
2307{
2308 /* printable ascii characters, excluding ANON_VMA_NAME_INVALID_CHARS */
2309 return ch > 0x1f && ch < 0x7f &&
2310 !strchr(ANON_VMA_NAME_INVALID_CHARS, ch);
2311}
2312
2313static int prctl_set_vma(unsigned long opt, unsigned long addr,
2314 unsigned long size, unsigned long arg)
2315{
2316 struct mm_struct *mm = current->mm;
2317 const char __user *uname;
2318 struct anon_vma_name *anon_name = NULL;
2319 int error;
2320
2321 switch (opt) {
2322 case PR_SET_VMA_ANON_NAME:
2323 uname = (const char __user *)arg;
2324 if (uname) {
2325 char *name, *pch;
2326
2327 name = strndup_user(uname, ANON_VMA_NAME_MAX_LEN);
2328 if (IS_ERR(name))
2329 return PTR_ERR(name);
2330
2331 for (pch = name; *pch != '\0'; pch++) {
2332 if (!is_valid_name_char(*pch)) {
2333 kfree(name);
2334 return -EINVAL;
2335 }
2336 }
2337 /* anon_vma has its own copy */
2338 anon_name = anon_vma_name_alloc(name);
2339 kfree(name);
2340 if (!anon_name)
2341 return -ENOMEM;
2342
2343 }
2344
2345 mmap_write_lock(mm);
2346 error = madvise_set_anon_name(mm, addr, size, anon_name);
2347 mmap_write_unlock(mm);
2348 anon_vma_name_put(anon_name);
2349 break;
2350 default:
2351 error = -EINVAL;
2352 }
2353
2354 return error;
2355}
2356
2357#else /* CONFIG_ANON_VMA_NAME */
2358static int prctl_set_vma(unsigned long opt, unsigned long start,
2359 unsigned long size, unsigned long arg)
2360{
2361 return -EINVAL;
2362}
2363#endif /* CONFIG_ANON_VMA_NAME */
2364
2365static inline int prctl_set_mdwe(unsigned long bits, unsigned long arg3,
2366 unsigned long arg4, unsigned long arg5)
2367{
2368 if (arg3 || arg4 || arg5)
2369 return -EINVAL;
2370
2371 if (bits & ~(PR_MDWE_REFUSE_EXEC_GAIN))
2372 return -EINVAL;
2373
2374 if (bits & PR_MDWE_REFUSE_EXEC_GAIN)
2375 set_bit(MMF_HAS_MDWE, &current->mm->flags);
2376 else if (test_bit(MMF_HAS_MDWE, &current->mm->flags))
2377 return -EPERM; /* Cannot unset the flag */
2378
2379 return 0;
2380}
2381
2382static inline int prctl_get_mdwe(unsigned long arg2, unsigned long arg3,
2383 unsigned long arg4, unsigned long arg5)
2384{
2385 if (arg2 || arg3 || arg4 || arg5)
2386 return -EINVAL;
2387
2388 return test_bit(MMF_HAS_MDWE, &current->mm->flags) ?
2389 PR_MDWE_REFUSE_EXEC_GAIN : 0;
2390}
2391
2392static int prctl_get_auxv(void __user *addr, unsigned long len)
2393{
2394 struct mm_struct *mm = current->mm;
2395 unsigned long size = min_t(unsigned long, sizeof(mm->saved_auxv), len);
2396
2397 if (size && copy_to_user(addr, mm->saved_auxv, size))
2398 return -EFAULT;
2399 return sizeof(mm->saved_auxv);
2400}
2401
2402SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
2403 unsigned long, arg4, unsigned long, arg5)
2404{
2405 struct task_struct *me = current;
2406 unsigned char comm[sizeof(me->comm)];
2407 long error;
2408
2409 error = security_task_prctl(option, arg2, arg3, arg4, arg5);
2410 if (error != -ENOSYS)
2411 return error;
2412
2413 error = 0;
2414 switch (option) {
2415 case PR_SET_PDEATHSIG:
2416 if (!valid_signal(arg2)) {
2417 error = -EINVAL;
2418 break;
2419 }
2420 me->pdeath_signal = arg2;
2421 break;
2422 case PR_GET_PDEATHSIG:
2423 error = put_user(me->pdeath_signal, (int __user *)arg2);
2424 break;
2425 case PR_GET_DUMPABLE:
2426 error = get_dumpable(me->mm);
2427 break;
2428 case PR_SET_DUMPABLE:
2429 if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) {
2430 error = -EINVAL;
2431 break;
2432 }
2433 set_dumpable(me->mm, arg2);
2434 break;
2435
2436 case PR_SET_UNALIGN:
2437 error = SET_UNALIGN_CTL(me, arg2);
2438 break;
2439 case PR_GET_UNALIGN:
2440 error = GET_UNALIGN_CTL(me, arg2);
2441 break;
2442 case PR_SET_FPEMU:
2443 error = SET_FPEMU_CTL(me, arg2);
2444 break;
2445 case PR_GET_FPEMU:
2446 error = GET_FPEMU_CTL(me, arg2);
2447 break;
2448 case PR_SET_FPEXC:
2449 error = SET_FPEXC_CTL(me, arg2);
2450 break;
2451 case PR_GET_FPEXC:
2452 error = GET_FPEXC_CTL(me, arg2);
2453 break;
2454 case PR_GET_TIMING:
2455 error = PR_TIMING_STATISTICAL;
2456 break;
2457 case PR_SET_TIMING:
2458 if (arg2 != PR_TIMING_STATISTICAL)
2459 error = -EINVAL;
2460 break;
2461 case PR_SET_NAME:
2462 comm[sizeof(me->comm) - 1] = 0;
2463 if (strncpy_from_user(comm, (char __user *)arg2,
2464 sizeof(me->comm) - 1) < 0)
2465 return -EFAULT;
2466 set_task_comm(me, comm);
2467 proc_comm_connector(me);
2468 break;
2469 case PR_GET_NAME:
2470 get_task_comm(comm, me);
2471 if (copy_to_user((char __user *)arg2, comm, sizeof(comm)))
2472 return -EFAULT;
2473 break;
2474 case PR_GET_ENDIAN:
2475 error = GET_ENDIAN(me, arg2);
2476 break;
2477 case PR_SET_ENDIAN:
2478 error = SET_ENDIAN(me, arg2);
2479 break;
2480 case PR_GET_SECCOMP:
2481 error = prctl_get_seccomp();
2482 break;
2483 case PR_SET_SECCOMP:
2484 error = prctl_set_seccomp(arg2, (char __user *)arg3);
2485 break;
2486 case PR_GET_TSC:
2487 error = GET_TSC_CTL(arg2);
2488 break;
2489 case PR_SET_TSC:
2490 error = SET_TSC_CTL(arg2);
2491 break;
2492 case PR_TASK_PERF_EVENTS_DISABLE:
2493 error = perf_event_task_disable();
2494 break;
2495 case PR_TASK_PERF_EVENTS_ENABLE:
2496 error = perf_event_task_enable();
2497 break;
2498 case PR_GET_TIMERSLACK:
2499 if (current->timer_slack_ns > ULONG_MAX)
2500 error = ULONG_MAX;
2501 else
2502 error = current->timer_slack_ns;
2503 break;
2504 case PR_SET_TIMERSLACK:
2505 if (arg2 <= 0)
2506 current->timer_slack_ns =
2507 current->default_timer_slack_ns;
2508 else
2509 current->timer_slack_ns = arg2;
2510 break;
2511 case PR_MCE_KILL:
2512 if (arg4 | arg5)
2513 return -EINVAL;
2514 switch (arg2) {
2515 case PR_MCE_KILL_CLEAR:
2516 if (arg3 != 0)
2517 return -EINVAL;
2518 current->flags &= ~PF_MCE_PROCESS;
2519 break;
2520 case PR_MCE_KILL_SET:
2521 current->flags |= PF_MCE_PROCESS;
2522 if (arg3 == PR_MCE_KILL_EARLY)
2523 current->flags |= PF_MCE_EARLY;
2524 else if (arg3 == PR_MCE_KILL_LATE)
2525 current->flags &= ~PF_MCE_EARLY;
2526 else if (arg3 == PR_MCE_KILL_DEFAULT)
2527 current->flags &=
2528 ~(PF_MCE_EARLY|PF_MCE_PROCESS);
2529 else
2530 return -EINVAL;
2531 break;
2532 case PR_GET_AUXV:
2533 if (arg4 || arg5)
2534 return -EINVAL;
2535 error = prctl_get_auxv((void __user *)arg2, arg3);
2536 break;
2537 default:
2538 return -EINVAL;
2539 }
2540 break;
2541 case PR_MCE_KILL_GET:
2542 if (arg2 | arg3 | arg4 | arg5)
2543 return -EINVAL;
2544 if (current->flags & PF_MCE_PROCESS)
2545 error = (current->flags & PF_MCE_EARLY) ?
2546 PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE;
2547 else
2548 error = PR_MCE_KILL_DEFAULT;
2549 break;
2550 case PR_SET_MM:
2551 error = prctl_set_mm(arg2, arg3, arg4, arg5);
2552 break;
2553 case PR_GET_TID_ADDRESS:
2554 error = prctl_get_tid_address(me, (int __user * __user *)arg2);
2555 break;
2556 case PR_SET_CHILD_SUBREAPER:
2557 me->signal->is_child_subreaper = !!arg2;
2558 if (!arg2)
2559 break;
2560
2561 walk_process_tree(me, propagate_has_child_subreaper, NULL);
2562 break;
2563 case PR_GET_CHILD_SUBREAPER:
2564 error = put_user(me->signal->is_child_subreaper,
2565 (int __user *)arg2);
2566 break;
2567 case PR_SET_NO_NEW_PRIVS:
2568 if (arg2 != 1 || arg3 || arg4 || arg5)
2569 return -EINVAL;
2570
2571 task_set_no_new_privs(current);
2572 break;
2573 case PR_GET_NO_NEW_PRIVS:
2574 if (arg2 || arg3 || arg4 || arg5)
2575 return -EINVAL;
2576 return task_no_new_privs(current) ? 1 : 0;
2577 case PR_GET_THP_DISABLE:
2578 if (arg2 || arg3 || arg4 || arg5)
2579 return -EINVAL;
2580 error = !!test_bit(MMF_DISABLE_THP, &me->mm->flags);
2581 break;
2582 case PR_SET_THP_DISABLE:
2583 if (arg3 || arg4 || arg5)
2584 return -EINVAL;
2585 if (mmap_write_lock_killable(me->mm))
2586 return -EINTR;
2587 if (arg2)
2588 set_bit(MMF_DISABLE_THP, &me->mm->flags);
2589 else
2590 clear_bit(MMF_DISABLE_THP, &me->mm->flags);
2591 mmap_write_unlock(me->mm);
2592 break;
2593 case PR_MPX_ENABLE_MANAGEMENT:
2594 case PR_MPX_DISABLE_MANAGEMENT:
2595 /* No longer implemented: */
2596 return -EINVAL;
2597 case PR_SET_FP_MODE:
2598 error = SET_FP_MODE(me, arg2);
2599 break;
2600 case PR_GET_FP_MODE:
2601 error = GET_FP_MODE(me);
2602 break;
2603 case PR_SVE_SET_VL:
2604 error = SVE_SET_VL(arg2);
2605 break;
2606 case PR_SVE_GET_VL:
2607 error = SVE_GET_VL();
2608 break;
2609 case PR_SME_SET_VL:
2610 error = SME_SET_VL(arg2);
2611 break;
2612 case PR_SME_GET_VL:
2613 error = SME_GET_VL();
2614 break;
2615 case PR_GET_SPECULATION_CTRL:
2616 if (arg3 || arg4 || arg5)
2617 return -EINVAL;
2618 error = arch_prctl_spec_ctrl_get(me, arg2);
2619 break;
2620 case PR_SET_SPECULATION_CTRL:
2621 if (arg4 || arg5)
2622 return -EINVAL;
2623 error = arch_prctl_spec_ctrl_set(me, arg2, arg3);
2624 break;
2625 case PR_PAC_RESET_KEYS:
2626 if (arg3 || arg4 || arg5)
2627 return -EINVAL;
2628 error = PAC_RESET_KEYS(me, arg2);
2629 break;
2630 case PR_PAC_SET_ENABLED_KEYS:
2631 if (arg4 || arg5)
2632 return -EINVAL;
2633 error = PAC_SET_ENABLED_KEYS(me, arg2, arg3);
2634 break;
2635 case PR_PAC_GET_ENABLED_KEYS:
2636 if (arg2 || arg3 || arg4 || arg5)
2637 return -EINVAL;
2638 error = PAC_GET_ENABLED_KEYS(me);
2639 break;
2640 case PR_SET_TAGGED_ADDR_CTRL:
2641 if (arg3 || arg4 || arg5)
2642 return -EINVAL;
2643 error = SET_TAGGED_ADDR_CTRL(arg2);
2644 break;
2645 case PR_GET_TAGGED_ADDR_CTRL:
2646 if (arg2 || arg3 || arg4 || arg5)
2647 return -EINVAL;
2648 error = GET_TAGGED_ADDR_CTRL();
2649 break;
2650 case PR_SET_IO_FLUSHER:
2651 if (!capable(CAP_SYS_RESOURCE))
2652 return -EPERM;
2653
2654 if (arg3 || arg4 || arg5)
2655 return -EINVAL;
2656
2657 if (arg2 == 1)
2658 current->flags |= PR_IO_FLUSHER;
2659 else if (!arg2)
2660 current->flags &= ~PR_IO_FLUSHER;
2661 else
2662 return -EINVAL;
2663 break;
2664 case PR_GET_IO_FLUSHER:
2665 if (!capable(CAP_SYS_RESOURCE))
2666 return -EPERM;
2667
2668 if (arg2 || arg3 || arg4 || arg5)
2669 return -EINVAL;
2670
2671 error = (current->flags & PR_IO_FLUSHER) == PR_IO_FLUSHER;
2672 break;
2673 case PR_SET_SYSCALL_USER_DISPATCH:
2674 error = set_syscall_user_dispatch(arg2, arg3, arg4,
2675 (char __user *) arg5);
2676 break;
2677#ifdef CONFIG_SCHED_CORE
2678 case PR_SCHED_CORE:
2679 error = sched_core_share_pid(arg2, arg3, arg4, arg5);
2680 break;
2681#endif
2682 case PR_SET_MDWE:
2683 error = prctl_set_mdwe(arg2, arg3, arg4, arg5);
2684 break;
2685 case PR_GET_MDWE:
2686 error = prctl_get_mdwe(arg2, arg3, arg4, arg5);
2687 break;
2688 case PR_SET_VMA:
2689 error = prctl_set_vma(arg2, arg3, arg4, arg5);
2690 break;
2691#ifdef CONFIG_KSM
2692 case PR_SET_MEMORY_MERGE:
2693 if (arg3 || arg4 || arg5)
2694 return -EINVAL;
2695 if (mmap_write_lock_killable(me->mm))
2696 return -EINTR;
2697
2698 if (arg2)
2699 error = ksm_enable_merge_any(me->mm);
2700 else
2701 error = ksm_disable_merge_any(me->mm);
2702 mmap_write_unlock(me->mm);
2703 break;
2704 case PR_GET_MEMORY_MERGE:
2705 if (arg2 || arg3 || arg4 || arg5)
2706 return -EINVAL;
2707
2708 error = !!test_bit(MMF_VM_MERGE_ANY, &me->mm->flags);
2709 break;
2710#endif
2711 default:
2712 error = -EINVAL;
2713 break;
2714 }
2715 return error;
2716}
2717
2718SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
2719 struct getcpu_cache __user *, unused)
2720{
2721 int err = 0;
2722 int cpu = raw_smp_processor_id();
2723
2724 if (cpup)
2725 err |= put_user(cpu, cpup);
2726 if (nodep)
2727 err |= put_user(cpu_to_node(cpu), nodep);
2728 return err ? -EFAULT : 0;
2729}
2730
2731/**
2732 * do_sysinfo - fill in sysinfo struct
2733 * @info: pointer to buffer to fill
2734 */
2735static int do_sysinfo(struct sysinfo *info)
2736{
2737 unsigned long mem_total, sav_total;
2738 unsigned int mem_unit, bitcount;
2739 struct timespec64 tp;
2740
2741 memset(info, 0, sizeof(struct sysinfo));
2742
2743 ktime_get_boottime_ts64(&tp);
2744 timens_add_boottime(&tp);
2745 info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0);
2746
2747 get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT);
2748
2749 info->procs = nr_threads;
2750
2751 si_meminfo(info);
2752 si_swapinfo(info);
2753
2754 /*
2755 * If the sum of all the available memory (i.e. ram + swap)
2756 * is less than can be stored in a 32 bit unsigned long then
2757 * we can be binary compatible with 2.2.x kernels. If not,
2758 * well, in that case 2.2.x was broken anyways...
2759 *
2760 * -Erik Andersen <[email protected]>
2761 */
2762
2763 mem_total = info->totalram + info->totalswap;
2764 if (mem_total < info->totalram || mem_total < info->totalswap)
2765 goto out;
2766 bitcount = 0;
2767 mem_unit = info->mem_unit;
2768 while (mem_unit > 1) {
2769 bitcount++;
2770 mem_unit >>= 1;
2771 sav_total = mem_total;
2772 mem_total <<= 1;
2773 if (mem_total < sav_total)
2774 goto out;
2775 }
2776
2777 /*
2778 * If mem_total did not overflow, multiply all memory values by
2779 * info->mem_unit and set it to 1. This leaves things compatible
2780 * with 2.2.x, and also retains compatibility with earlier 2.4.x
2781 * kernels...
2782 */
2783
2784 info->mem_unit = 1;
2785 info->totalram <<= bitcount;
2786 info->freeram <<= bitcount;
2787 info->sharedram <<= bitcount;
2788 info->bufferram <<= bitcount;
2789 info->totalswap <<= bitcount;
2790 info->freeswap <<= bitcount;
2791 info->totalhigh <<= bitcount;
2792 info->freehigh <<= bitcount;
2793
2794out:
2795 return 0;
2796}
2797
2798SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info)
2799{
2800 struct sysinfo val;
2801
2802 do_sysinfo(&val);
2803
2804 if (copy_to_user(info, &val, sizeof(struct sysinfo)))
2805 return -EFAULT;
2806
2807 return 0;
2808}
2809
2810#ifdef CONFIG_COMPAT
2811struct compat_sysinfo {
2812 s32 uptime;
2813 u32 loads[3];
2814 u32 totalram;
2815 u32 freeram;
2816 u32 sharedram;
2817 u32 bufferram;
2818 u32 totalswap;
2819 u32 freeswap;
2820 u16 procs;
2821 u16 pad;
2822 u32 totalhigh;
2823 u32 freehigh;
2824 u32 mem_unit;
2825 char _f[20-2*sizeof(u32)-sizeof(int)];
2826};
2827
2828COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
2829{
2830 struct sysinfo s;
2831 struct compat_sysinfo s_32;
2832
2833 do_sysinfo(&s);
2834
2835 /* Check to see if any memory value is too large for 32-bit and scale
2836 * down if needed
2837 */
2838 if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) {
2839 int bitcount = 0;
2840
2841 while (s.mem_unit < PAGE_SIZE) {
2842 s.mem_unit <<= 1;
2843 bitcount++;
2844 }
2845
2846 s.totalram >>= bitcount;
2847 s.freeram >>= bitcount;
2848 s.sharedram >>= bitcount;
2849 s.bufferram >>= bitcount;
2850 s.totalswap >>= bitcount;
2851 s.freeswap >>= bitcount;
2852 s.totalhigh >>= bitcount;
2853 s.freehigh >>= bitcount;
2854 }
2855
2856 memset(&s_32, 0, sizeof(s_32));
2857 s_32.uptime = s.uptime;
2858 s_32.loads[0] = s.loads[0];
2859 s_32.loads[1] = s.loads[1];
2860 s_32.loads[2] = s.loads[2];
2861 s_32.totalram = s.totalram;
2862 s_32.freeram = s.freeram;
2863 s_32.sharedram = s.sharedram;
2864 s_32.bufferram = s.bufferram;
2865 s_32.totalswap = s.totalswap;
2866 s_32.freeswap = s.freeswap;
2867 s_32.procs = s.procs;
2868 s_32.totalhigh = s.totalhigh;
2869 s_32.freehigh = s.freehigh;
2870 s_32.mem_unit = s.mem_unit;
2871 if (copy_to_user(info, &s_32, sizeof(s_32)))
2872 return -EFAULT;
2873 return 0;
2874}
2875#endif /* CONFIG_COMPAT */