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mm: unexport unmap_kernel_range_noflush
[thirdparty/linux.git] / kernel / sys.c
CommitLineData
b2441318 1// SPDX-License-Identifier: GPL-2.0
1da177e4
LT		 2/*
3 * linux/kernel/sys.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 */
7
9984de1a 8#include <linux/export.h>
1da177e4
LT		 9#include <linux/mm.h>
10#include <linux/utsname.h>
11#include <linux/mman.h>
1da177e4
LT		 12#include <linux/reboot.h>
13#include <linux/prctl.h>
1da177e4
LT		 14#include <linux/highuid.h>
15#include <linux/fs.h>
74da1ff7 16#include <linux/kmod.h>
cdd6c482 17#include <linux/perf_event.h>
3e88c553 18#include <linux/resource.h>
dc009d92 19#include <linux/kernel.h>
1da177e4 20#include <linux/workqueue.h>
c59ede7b 21#include <linux/capability.h>
1da177e4
LT		 22#include <linux/device.h>
23#include <linux/key.h>
24#include <linux/times.h>
25#include <linux/posix-timers.h>
26#include <linux/security.h>
27#include <linux/dcookies.h>
28#include <linux/suspend.h>
29#include <linux/tty.h>
7ed20e1a 30#include <linux/signal.h>
9f46080c 31#include <linux/cn_proc.h>
3cfc348b 32#include <linux/getcpu.h>
6eaeeaba 33#include <linux/task_io_accounting_ops.h>
1d9d02fe 34#include <linux/seccomp.h>
4047727e 35#include <linux/cpu.h>
e28cbf22 36#include <linux/personality.h>
e3d5a27d 37#include <linux/ptrace.h>
5ad4e53b 38#include <linux/fs_struct.h>
b32dfe37
CG		 39#include <linux/file.h>
40#include <linux/mount.h>
5a0e3ad6 41#include <linux/gfp.h>
40dc166c 42#include <linux/syscore_ops.h>
be27425d
AK		 43#include <linux/version.h>
44#include <linux/ctype.h>
1da177e4
LT		 45
46#include <linux/compat.h>
47#include <linux/syscalls.h>
00d7c05a 48#include <linux/kprobes.h>
acce292c 49#include <linux/user_namespace.h>
ecc421e0 50#include <linux/time_namespace.h>
7fe5e042 51#include <linux/binfmts.h>
1da177e4 52
4a22f166 53#include <linux/sched.h>
4eb5aaa3 54#include <linux/sched/autogroup.h>
4f17722c 55#include <linux/sched/loadavg.h>
03441a34 56#include <linux/sched/stat.h>
6e84f315 57#include <linux/sched/mm.h>
f7ccbae4 58#include <linux/sched/coredump.h>
29930025 59#include <linux/sched/task.h>
32ef5517 60#include <linux/sched/cputime.h>
4a22f166
SR		 61#include <linux/rcupdate.h>
62#include <linux/uidgid.h>
63#include <linux/cred.h>
64
b617cfc8
TG		 65#include <linux/nospec.h>
66
04c6862c 67#include <linux/kmsg_dump.h>
be27425d
AK		 68/* Move somewhere else to avoid recompiling? */
69#include <generated/utsrelease.h>
04c6862c 70
7c0f6ba6 71#include <linux/uaccess.h>
1da177e4
LT		 72#include <asm/io.h>
73#include <asm/unistd.h>
74
e530dca5
DB		 75#include "uid16.h"
76
1da177e4 77#ifndef SET_UNALIGN_CTL
ec94fc3d 78# define SET_UNALIGN_CTL(a, b) (-EINVAL)
1da177e4
LT		 79#endif
80#ifndef GET_UNALIGN_CTL
ec94fc3d 81# define GET_UNALIGN_CTL(a, b) (-EINVAL)
1da177e4
LT		 82#endif
83#ifndef SET_FPEMU_CTL
ec94fc3d 84# define SET_FPEMU_CTL(a, b) (-EINVAL)
1da177e4
LT		 85#endif
86#ifndef GET_FPEMU_CTL
ec94fc3d 87# define GET_FPEMU_CTL(a, b) (-EINVAL)
1da177e4
LT		 88#endif
89#ifndef SET_FPEXC_CTL
ec94fc3d 90# define SET_FPEXC_CTL(a, b) (-EINVAL)
1da177e4
LT		 91#endif
92#ifndef GET_FPEXC_CTL
ec94fc3d 93# define GET_FPEXC_CTL(a, b) (-EINVAL)
1da177e4 94#endif
651d765d 95#ifndef GET_ENDIAN
ec94fc3d 96# define GET_ENDIAN(a, b) (-EINVAL)
651d765d
AB		 97#endif
98#ifndef SET_ENDIAN
ec94fc3d 99# define SET_ENDIAN(a, b) (-EINVAL)
651d765d 100#endif
8fb402bc
EB		 101#ifndef GET_TSC_CTL
102# define GET_TSC_CTL(a) (-EINVAL)
103#endif
104#ifndef SET_TSC_CTL
105# define SET_TSC_CTL(a) (-EINVAL)
106#endif
9791554b
PB		 107#ifndef GET_FP_MODE
108# define GET_FP_MODE(a) (-EINVAL)
109#endif
110#ifndef SET_FP_MODE
111# define SET_FP_MODE(a,b) (-EINVAL)
112#endif
2d2123bc
DM		 113#ifndef SVE_SET_VL
114# define SVE_SET_VL(a) (-EINVAL)
115#endif
116#ifndef SVE_GET_VL
117# define SVE_GET_VL() (-EINVAL)
118#endif
ba830885
KM		 119#ifndef PAC_RESET_KEYS
120# define PAC_RESET_KEYS(a, b) (-EINVAL)
121#endif
63f0c603
CM		 122#ifndef SET_TAGGED_ADDR_CTRL
123# define SET_TAGGED_ADDR_CTRL(a) (-EINVAL)
124#endif
125#ifndef GET_TAGGED_ADDR_CTRL
126# define GET_TAGGED_ADDR_CTRL() (-EINVAL)
127#endif
1da177e4
LT		 128
129/*
130 * this is where the system-wide overflow UID and GID are defined, for
131 * architectures that now have 32-bit UID/GID but didn't in the past
132 */
133
134int overflowuid = DEFAULT_OVERFLOWUID;
135int overflowgid = DEFAULT_OVERFLOWGID;
136
1da177e4
LT		 137EXPORT_SYMBOL(overflowuid);
138EXPORT_SYMBOL(overflowgid);
1da177e4
LT		 139
140/*
141 * the same as above, but for filesystems which can only store a 16-bit
142 * UID and GID. as such, this is needed on all architectures
143 */
144
145int fs_overflowuid = DEFAULT_FS_OVERFLOWUID;
8b2770a4 146int fs_overflowgid = DEFAULT_FS_OVERFLOWGID;
1da177e4
LT		 147
148EXPORT_SYMBOL(fs_overflowuid);
149EXPORT_SYMBOL(fs_overflowgid);
150
fc832ad3
SH		 151/*
152 * Returns true if current's euid is same as p's uid or euid,
153 * or has CAP_SYS_NICE to p's user_ns.
154 *
155 * Called with rcu_read_lock, creds are safe
156 */
157static bool set_one_prio_perm(struct task_struct *p)
158{
159 const struct cred *cred = current_cred(), *pcred = __task_cred(p);
160
5af66203
EB		 161 if (uid_eq(pcred->uid, cred->euid) ||
162 uid_eq(pcred->euid, cred->euid))
fc832ad3 163 return true;
c4a4d603 164 if (ns_capable(pcred->user_ns, CAP_SYS_NICE))
fc832ad3
SH		 165 return true;
166 return false;
167}
168
c69e8d9c
DH		 169/*
170 * set the priority of a task
171 * - the caller must hold the RCU read lock
172 */
1da177e4
LT		 173static int set_one_prio(struct task_struct *p, int niceval, int error)
174{
175 int no_nice;
176
fc832ad3 177 if (!set_one_prio_perm(p)) {
1da177e4
LT		 178 error = -EPERM;
179 goto out;
180 }
e43379f1 181 if (niceval < task_nice(p) && !can_nice(p, niceval)) {
1da177e4
LT		 182 error = -EACCES;
183 goto out;
184 }
185 no_nice = security_task_setnice(p, niceval);
186 if (no_nice) {
187 error = no_nice;
188 goto out;
189 }
190 if (error == -ESRCH)
191 error = 0;
192 set_user_nice(p, niceval);
193out:
194 return error;
195}
196
754fe8d2 197SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
1da177e4
LT		 198{
199 struct task_struct *g, *p;
200 struct user_struct *user;
86a264ab 201 const struct cred *cred = current_cred();
1da177e4 202 int error = -EINVAL;
41487c65 203 struct pid *pgrp;
7b44ab97 204 kuid_t uid;
1da177e4 205
3e88c553 206 if (which > PRIO_USER || which < PRIO_PROCESS)
1da177e4
LT		 207 goto out;
208
209 /* normalize: avoid signed division (rounding problems) */
210 error = -ESRCH;
c4a4d2f4
DY		 211 if (niceval < MIN_NICE)
212 niceval = MIN_NICE;
213 if (niceval > MAX_NICE)
214 niceval = MAX_NICE;
1da177e4 215
d4581a23 216 rcu_read_lock();
1da177e4
LT		 217 read_lock(&tasklist_lock);
218 switch (which) {
ec94fc3d 219 case PRIO_PROCESS:
220 if (who)
221 p = find_task_by_vpid(who);
222 else
223 p = current;
224 if (p)
225 error = set_one_prio(p, niceval, error);
226 break;
227 case PRIO_PGRP:
228 if (who)
229 pgrp = find_vpid(who);
230 else
231 pgrp = task_pgrp(current);
232 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
233 error = set_one_prio(p, niceval, error);
234 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
235 break;
236 case PRIO_USER:
237 uid = make_kuid(cred->user_ns, who);
238 user = cred->user;
239 if (!who)
240 uid = cred->uid;
241 else if (!uid_eq(uid, cred->uid)) {
242 user = find_user(uid);
243 if (!user)
86a264ab 244 goto out_unlock; /* No processes for this user */
ec94fc3d 245 }
246 do_each_thread(g, p) {
8639b461 247 if (uid_eq(task_uid(p), uid) && task_pid_vnr(p))
ec94fc3d 248 error = set_one_prio(p, niceval, error);
249 } while_each_thread(g, p);
250 if (!uid_eq(uid, cred->uid))
251 free_uid(user); /* For find_user() */
252 break;
1da177e4
LT		 253 }
254out_unlock:
255 read_unlock(&tasklist_lock);
d4581a23 256 rcu_read_unlock();
1da177e4
LT		 257out:
258 return error;
259}
260
261/*
262 * Ugh. To avoid negative return values, "getpriority()" will
263 * not return the normal nice-value, but a negated value that
264 * has been offset by 20 (ie it returns 40..1 instead of -20..19)
265 * to stay compatible.
266 */
754fe8d2 267SYSCALL_DEFINE2(getpriority, int, which, int, who)
1da177e4
LT		 268{
269 struct task_struct *g, *p;
270 struct user_struct *user;
86a264ab 271 const struct cred *cred = current_cred();
1da177e4 272 long niceval, retval = -ESRCH;
41487c65 273 struct pid *pgrp;
7b44ab97 274 kuid_t uid;
1da177e4 275
3e88c553 276 if (which > PRIO_USER || which < PRIO_PROCESS)
1da177e4
LT		 277 return -EINVAL;
278
70118837 279 rcu_read_lock();
1da177e4
LT		 280 read_lock(&tasklist_lock);
281 switch (which) {
ec94fc3d 282 case PRIO_PROCESS:
283 if (who)
284 p = find_task_by_vpid(who);
285 else
286 p = current;
287 if (p) {
288 niceval = nice_to_rlimit(task_nice(p));
289 if (niceval > retval)
290 retval = niceval;
291 }
292 break;
293 case PRIO_PGRP:
294 if (who)
295 pgrp = find_vpid(who);
296 else
297 pgrp = task_pgrp(current);
298 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
299 niceval = nice_to_rlimit(task_nice(p));
300 if (niceval > retval)
301 retval = niceval;
302 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
303 break;
304 case PRIO_USER:
305 uid = make_kuid(cred->user_ns, who);
306 user = cred->user;
307 if (!who)
308 uid = cred->uid;
309 else if (!uid_eq(uid, cred->uid)) {
310 user = find_user(uid);
311 if (!user)
312 goto out_unlock; /* No processes for this user */
313 }
314 do_each_thread(g, p) {
8639b461 315 if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) {
7aa2c016 316 niceval = nice_to_rlimit(task_nice(p));
1da177e4
LT		 317 if (niceval > retval)
318 retval = niceval;
319 }
ec94fc3d 320 } while_each_thread(g, p);
321 if (!uid_eq(uid, cred->uid))
322 free_uid(user); /* for find_user() */
323 break;
1da177e4
LT		 324 }
325out_unlock:
326 read_unlock(&tasklist_lock);
70118837 327 rcu_read_unlock();
1da177e4
LT		 328
329 return retval;
330}
331
1da177e4
LT		 332/*
333 * Unprivileged users may change the real gid to the effective gid
334 * or vice versa. (BSD-style)
335 *
336 * If you set the real gid at all, or set the effective gid to a value not
337 * equal to the real gid, then the saved gid is set to the new effective gid.
338 *
339 * This makes it possible for a setgid program to completely drop its
340 * privileges, which is often a useful assertion to make when you are doing
341 * a security audit over a program.
342 *
343 * The general idea is that a program which uses just setregid() will be
344 * 100% compatible with BSD. A program which uses just setgid() will be
ec94fc3d 345 * 100% compatible with POSIX with saved IDs.
1da177e4
LT		 346 *
347 * SMP: There are not races, the GIDs are checked only by filesystem
348 * operations (as far as semantic preservation is concerned).
349 */
2813893f 350#ifdef CONFIG_MULTIUSER
e530dca5 351long __sys_setregid(gid_t rgid, gid_t egid)
1da177e4 352{
a29c33f4 353 struct user_namespace *ns = current_user_ns();
d84f4f99
DH		 354 const struct cred *old;
355 struct cred *new;
1da177e4 356 int retval;
a29c33f4
EB		 357 kgid_t krgid, kegid;
358
359 krgid = make_kgid(ns, rgid);
360 kegid = make_kgid(ns, egid);
361
362 if ((rgid != (gid_t) -1) && !gid_valid(krgid))
363 return -EINVAL;
364 if ((egid != (gid_t) -1) && !gid_valid(kegid))
365 return -EINVAL;
1da177e4 366
d84f4f99
DH		 367 new = prepare_creds();
368 if (!new)
369 return -ENOMEM;
370 old = current_cred();
371
d84f4f99 372 retval = -EPERM;
1da177e4 373 if (rgid != (gid_t) -1) {
a29c33f4
EB		 374 if (gid_eq(old->gid, krgid) ||
375 gid_eq(old->egid, krgid) ||
c7b96acf 376 ns_capable(old->user_ns, CAP_SETGID))
a29c33f4 377 new->gid = krgid;
1da177e4 378 else
d84f4f99 379 goto error;
1da177e4
LT		 380 }
381 if (egid != (gid_t) -1) {
a29c33f4
EB		 382 if (gid_eq(old->gid, kegid) ||
383 gid_eq(old->egid, kegid) ||
384 gid_eq(old->sgid, kegid) ||
c7b96acf 385 ns_capable(old->user_ns, CAP_SETGID))
a29c33f4 386 new->egid = kegid;
756184b7 387 else
d84f4f99 388 goto error;
1da177e4 389 }
d84f4f99 390
1da177e4 391 if (rgid != (gid_t) -1 ||
a29c33f4 392 (egid != (gid_t) -1 && !gid_eq(kegid, old->gid)))
d84f4f99
DH		 393 new->sgid = new->egid;
394 new->fsgid = new->egid;
395
396 return commit_creds(new);
397
398error:
399 abort_creds(new);
400 return retval;
1da177e4
LT		 401}
402
e530dca5
DB		 403SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
404{
405 return __sys_setregid(rgid, egid);
406}
407
1da177e4 408/*
ec94fc3d 409 * setgid() is implemented like SysV w/ SAVED_IDS
1da177e4
LT		 410 *
411 * SMP: Same implicit races as above.
412 */
e530dca5 413long __sys_setgid(gid_t gid)
1da177e4 414{
a29c33f4 415 struct user_namespace *ns = current_user_ns();
d84f4f99
DH		 416 const struct cred *old;
417 struct cred *new;
1da177e4 418 int retval;
a29c33f4
EB		 419 kgid_t kgid;
420
421 kgid = make_kgid(ns, gid);
422 if (!gid_valid(kgid))
423 return -EINVAL;
1da177e4 424
d84f4f99
DH		 425 new = prepare_creds();
426 if (!new)
427 return -ENOMEM;
428 old = current_cred();
429
d84f4f99 430 retval = -EPERM;
c7b96acf 431 if (ns_capable(old->user_ns, CAP_SETGID))
a29c33f4
EB		 432 new->gid = new->egid = new->sgid = new->fsgid = kgid;
433 else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid))
434 new->egid = new->fsgid = kgid;
1da177e4 435 else
d84f4f99 436 goto error;
1da177e4 437
d84f4f99
DH		 438 return commit_creds(new);
439
440error:
441 abort_creds(new);
442 return retval;
1da177e4 443}
54e99124 444
e530dca5
DB		 445SYSCALL_DEFINE1(setgid, gid_t, gid)
446{
447 return __sys_setgid(gid);
448}
449
d84f4f99
DH		 450/*
451 * change the user struct in a credentials set to match the new UID
452 */
453static int set_user(struct cred *new)
1da177e4
LT		 454{
455 struct user_struct *new_user;
456
078de5f7 457 new_user = alloc_uid(new->uid);
1da177e4
LT		 458 if (!new_user)
459 return -EAGAIN;
460
72fa5997
VK		 461 /*
462 * We don't fail in case of NPROC limit excess here because too many
463 * poorly written programs don't check set*uid() return code, assuming
464 * it never fails if called by root. We may still enforce NPROC limit
465 * for programs doing set*uid()+execve() by harmlessly deferring the
466 * failure to the execve() stage.
467 */
78d7d407 468 if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) &&
72fa5997
VK		 469 new_user != INIT_USER)
470 current->flags |= PF_NPROC_EXCEEDED;
471 else
472 current->flags &= ~PF_NPROC_EXCEEDED;
1da177e4 473
d84f4f99
DH		 474 free_uid(new->user);
475 new->user = new_user;
1da177e4
LT		 476 return 0;
477}
478
479/*
480 * Unprivileged users may change the real uid to the effective uid
481 * or vice versa. (BSD-style)
482 *
483 * If you set the real uid at all, or set the effective uid to a value not
484 * equal to the real uid, then the saved uid is set to the new effective uid.
485 *
486 * This makes it possible for a setuid program to completely drop its
487 * privileges, which is often a useful assertion to make when you are doing
488 * a security audit over a program.
489 *
490 * The general idea is that a program which uses just setreuid() will be
491 * 100% compatible with BSD. A program which uses just setuid() will be
ec94fc3d 492 * 100% compatible with POSIX with saved IDs.
1da177e4 493 */
e530dca5 494long __sys_setreuid(uid_t ruid, uid_t euid)
1da177e4 495{
a29c33f4 496 struct user_namespace *ns = current_user_ns();
d84f4f99
DH		 497 const struct cred *old;
498 struct cred *new;
1da177e4 499 int retval;
a29c33f4
EB		 500 kuid_t kruid, keuid;
501
502 kruid = make_kuid(ns, ruid);
503 keuid = make_kuid(ns, euid);
504
505 if ((ruid != (uid_t) -1) && !uid_valid(kruid))
506 return -EINVAL;
507 if ((euid != (uid_t) -1) && !uid_valid(keuid))
508 return -EINVAL;
1da177e4 509
d84f4f99
DH		 510 new = prepare_creds();
511 if (!new)
512 return -ENOMEM;
513 old = current_cred();
514
d84f4f99 515 retval = -EPERM;
1da177e4 516 if (ruid != (uid_t) -1) {
a29c33f4
EB		 517 new->uid = kruid;
518 if (!uid_eq(old->uid, kruid) &&
519 !uid_eq(old->euid, kruid) &&
40852275 520 !ns_capable_setid(old->user_ns, CAP_SETUID))
d84f4f99 521 goto error;
1da177e4
LT		 522 }
523
524 if (euid != (uid_t) -1) {
a29c33f4
EB		 525 new->euid = keuid;
526 if (!uid_eq(old->uid, keuid) &&
527 !uid_eq(old->euid, keuid) &&
528 !uid_eq(old->suid, keuid) &&
40852275 529 !ns_capable_setid(old->user_ns, CAP_SETUID))
d84f4f99 530 goto error;
1da177e4
LT		 531 }
532
a29c33f4 533 if (!uid_eq(new->uid, old->uid)) {
54e99124
DG		 534 retval = set_user(new);
535 if (retval < 0)
536 goto error;
537 }
1da177e4 538 if (ruid != (uid_t) -1 ||
a29c33f4 539 (euid != (uid_t) -1 && !uid_eq(keuid, old->uid)))
d84f4f99
DH		 540 new->suid = new->euid;
541 new->fsuid = new->euid;
1da177e4 542
d84f4f99
DH		 543 retval = security_task_fix_setuid(new, old, LSM_SETID_RE);
544 if (retval < 0)
545 goto error;
1da177e4 546
d84f4f99 547 return commit_creds(new);
1da177e4 548
d84f4f99
DH		 549error:
550 abort_creds(new);
551 return retval;
552}
ec94fc3d 553
e530dca5
DB		 554SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
555{
556 return __sys_setreuid(ruid, euid);
557}
558
1da177e4 559/*
ec94fc3d 560 * setuid() is implemented like SysV with SAVED_IDS
561 *
1da177e4 562 * Note that SAVED_ID's is deficient in that a setuid root program
ec94fc3d 563 * like sendmail, for example, cannot set its uid to be a normal
1da177e4
LT		 564 * user and then switch back, because if you're root, setuid() sets
565 * the saved uid too. If you don't like this, blame the bright people
566 * in the POSIX committee and/or USG. Note that the BSD-style setreuid()
567 * will allow a root program to temporarily drop privileges and be able to
ec94fc3d 568 * regain them by swapping the real and effective uid.
1da177e4 569 */
e530dca5 570long __sys_setuid(uid_t uid)
1da177e4 571{
a29c33f4 572 struct user_namespace *ns = current_user_ns();
d84f4f99
DH		 573 const struct cred *old;
574 struct cred *new;
1da177e4 575 int retval;
a29c33f4
EB		 576 kuid_t kuid;
577
578 kuid = make_kuid(ns, uid);
579 if (!uid_valid(kuid))
580 return -EINVAL;
1da177e4 581
d84f4f99
DH		 582 new = prepare_creds();
583 if (!new)
584 return -ENOMEM;
585 old = current_cred();
586
d84f4f99 587 retval = -EPERM;
40852275 588 if (ns_capable_setid(old->user_ns, CAP_SETUID)) {
a29c33f4
EB		 589 new->suid = new->uid = kuid;
590 if (!uid_eq(kuid, old->uid)) {
54e99124
DG		 591 retval = set_user(new);
592 if (retval < 0)
593 goto error;
d84f4f99 594 }
a29c33f4 595 } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) {
d84f4f99 596 goto error;
1da177e4 597 }
1da177e4 598
a29c33f4 599 new->fsuid = new->euid = kuid;
d84f4f99
DH		 600
601 retval = security_task_fix_setuid(new, old, LSM_SETID_ID);
602 if (retval < 0)
603 goto error;
1da177e4 604
d84f4f99 605 return commit_creds(new);
1da177e4 606
d84f4f99
DH		 607error:
608 abort_creds(new);
609 return retval;
1da177e4
LT		 610}
611
e530dca5
DB		 612SYSCALL_DEFINE1(setuid, uid_t, uid)
613{
614 return __sys_setuid(uid);
615}
616
1da177e4
LT		 617
618/*
619 * This function implements a generic ability to update ruid, euid,
620 * and suid. This allows you to implement the 4.4 compatible seteuid().
621 */
e530dca5 622long __sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
1da177e4 623{
a29c33f4 624 struct user_namespace *ns = current_user_ns();
d84f4f99
DH		 625 const struct cred *old;
626 struct cred *new;
1da177e4 627 int retval;
a29c33f4
EB		 628 kuid_t kruid, keuid, ksuid;
629
630 kruid = make_kuid(ns, ruid);
631 keuid = make_kuid(ns, euid);
632 ksuid = make_kuid(ns, suid);
633
634 if ((ruid != (uid_t) -1) && !uid_valid(kruid))
635 return -EINVAL;
636
637 if ((euid != (uid_t) -1) && !uid_valid(keuid))
638 return -EINVAL;
639
640 if ((suid != (uid_t) -1) && !uid_valid(ksuid))
641 return -EINVAL;
1da177e4 642
d84f4f99
DH		 643 new = prepare_creds();
644 if (!new)
645 return -ENOMEM;
646
d84f4f99 647 old = current_cred();
1da177e4 648
d84f4f99 649 retval = -EPERM;
40852275 650 if (!ns_capable_setid(old->user_ns, CAP_SETUID)) {
a29c33f4
EB		 651 if (ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) &&
652 !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid))
d84f4f99 653 goto error;
a29c33f4
EB		 654 if (euid != (uid_t) -1 && !uid_eq(keuid, old->uid) &&
655 !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid))
d84f4f99 656 goto error;
a29c33f4
EB		 657 if (suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) &&
658 !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid))
d84f4f99 659 goto error;
1da177e4 660 }
d84f4f99 661
1da177e4 662 if (ruid != (uid_t) -1) {
a29c33f4
EB		 663 new->uid = kruid;
664 if (!uid_eq(kruid, old->uid)) {
54e99124
DG		 665 retval = set_user(new);
666 if (retval < 0)
667 goto error;
668 }
1da177e4 669 }
d84f4f99 670 if (euid != (uid_t) -1)
a29c33f4 671 new->euid = keuid;
1da177e4 672 if (suid != (uid_t) -1)
a29c33f4 673 new->suid = ksuid;
d84f4f99 674 new->fsuid = new->euid;
1da177e4 675
d84f4f99
DH		 676 retval = security_task_fix_setuid(new, old, LSM_SETID_RES);
677 if (retval < 0)
678 goto error;
1da177e4 679
d84f4f99 680 return commit_creds(new);
1da177e4 681
d84f4f99
DH		 682error:
683 abort_creds(new);
684 return retval;
1da177e4
LT		 685}
686
e530dca5
DB		 687SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid)
688{
689 return __sys_setresuid(ruid, euid, suid);
690}
691
a29c33f4 692SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp)
1da177e4 693{
86a264ab 694 const struct cred *cred = current_cred();
1da177e4 695 int retval;
a29c33f4
EB		 696 uid_t ruid, euid, suid;
697
698 ruid = from_kuid_munged(cred->user_ns, cred->uid);
699 euid = from_kuid_munged(cred->user_ns, cred->euid);
700 suid = from_kuid_munged(cred->user_ns, cred->suid);
1da177e4 701
ec94fc3d 702 retval = put_user(ruid, ruidp);
703 if (!retval) {
704 retval = put_user(euid, euidp);
705 if (!retval)
706 return put_user(suid, suidp);
707 }
1da177e4
LT		 708 return retval;
709}
710
711/*
712 * Same as above, but for rgid, egid, sgid.
713 */
e530dca5 714long __sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
1da177e4 715{
a29c33f4 716 struct user_namespace *ns = current_user_ns();
d84f4f99
DH		 717 const struct cred *old;
718 struct cred *new;
1da177e4 719 int retval;
a29c33f4
EB		 720 kgid_t krgid, kegid, ksgid;
721
722 krgid = make_kgid(ns, rgid);
723 kegid = make_kgid(ns, egid);
724 ksgid = make_kgid(ns, sgid);
725
726 if ((rgid != (gid_t) -1) && !gid_valid(krgid))
727 return -EINVAL;
728 if ((egid != (gid_t) -1) && !gid_valid(kegid))
729 return -EINVAL;
730 if ((sgid != (gid_t) -1) && !gid_valid(ksgid))
731 return -EINVAL;
1da177e4 732
d84f4f99
DH		 733 new = prepare_creds();
734 if (!new)
735 return -ENOMEM;
736 old = current_cred();
737
d84f4f99 738 retval = -EPERM;
c7b96acf 739 if (!ns_capable(old->user_ns, CAP_SETGID)) {
a29c33f4
EB		 740 if (rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) &&
741 !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid))
d84f4f99 742 goto error;
a29c33f4
EB		 743 if (egid != (gid_t) -1 && !gid_eq(kegid, old->gid) &&
744 !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid))
d84f4f99 745 goto error;
a29c33f4
EB		 746 if (sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) &&
747 !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid))
d84f4f99 748 goto error;
1da177e4 749 }
d84f4f99 750
1da177e4 751 if (rgid != (gid_t) -1)
a29c33f4 752 new->gid = krgid;
d84f4f99 753 if (egid != (gid_t) -1)
a29c33f4 754 new->egid = kegid;
1da177e4 755 if (sgid != (gid_t) -1)
a29c33f4 756 new->sgid = ksgid;
d84f4f99 757 new->fsgid = new->egid;
1da177e4 758
d84f4f99
DH		 759 return commit_creds(new);
760
761error:
762 abort_creds(new);
763 return retval;
1da177e4
LT		 764}
765
e530dca5
DB		 766SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid)
767{
768 return __sys_setresgid(rgid, egid, sgid);
769}
770
a29c33f4 771SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp)
1da177e4 772{
86a264ab 773 const struct cred *cred = current_cred();
1da177e4 774 int retval;
a29c33f4
EB		 775 gid_t rgid, egid, sgid;
776
777 rgid = from_kgid_munged(cred->user_ns, cred->gid);
778 egid = from_kgid_munged(cred->user_ns, cred->egid);
779 sgid = from_kgid_munged(cred->user_ns, cred->sgid);
1da177e4 780
ec94fc3d 781 retval = put_user(rgid, rgidp);
782 if (!retval) {
783 retval = put_user(egid, egidp);
784 if (!retval)
785 retval = put_user(sgid, sgidp);
786 }
1da177e4
LT		 787
788 return retval;
789}
790
791
792/*
793 * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This
794 * is used for "access()" and for the NFS daemon (letting nfsd stay at
795 * whatever uid it wants to). It normally shadows "euid", except when
796 * explicitly set by setfsuid() or for access..
797 */
e530dca5 798long __sys_setfsuid(uid_t uid)
1da177e4 799{
d84f4f99
DH		 800 const struct cred *old;
801 struct cred *new;
802 uid_t old_fsuid;
a29c33f4
EB		 803 kuid_t kuid;
804
805 old = current_cred();
806 old_fsuid = from_kuid_munged(old->user_ns, old->fsuid);
807
808 kuid = make_kuid(old->user_ns, uid);
809 if (!uid_valid(kuid))
810 return old_fsuid;
1da177e4 811
d84f4f99
DH		 812 new = prepare_creds();
813 if (!new)
a29c33f4 814 return old_fsuid;
1da177e4 815
a29c33f4
EB		 816 if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) ||
817 uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) ||
40852275 818 ns_capable_setid(old->user_ns, CAP_SETUID)) {
a29c33f4
EB		 819 if (!uid_eq(kuid, old->fsuid)) {
820 new->fsuid = kuid;
d84f4f99
DH		 821 if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0)
822 goto change_okay;
1da177e4 823 }
1da177e4
LT		 824 }
825
d84f4f99
DH		 826 abort_creds(new);
827 return old_fsuid;
1da177e4 828
d84f4f99
DH		 829change_okay:
830 commit_creds(new);
1da177e4
LT		 831 return old_fsuid;
832}
833
e530dca5
DB		 834SYSCALL_DEFINE1(setfsuid, uid_t, uid)
835{
836 return __sys_setfsuid(uid);
837}
838
1da177e4 839/*
f42df9e6 840 * Samma på svenska..
1da177e4 841 */
e530dca5 842long __sys_setfsgid(gid_t gid)
1da177e4 843{
d84f4f99
DH		 844 const struct cred *old;
845 struct cred *new;
846 gid_t old_fsgid;
a29c33f4
EB		 847 kgid_t kgid;
848
849 old = current_cred();
850 old_fsgid = from_kgid_munged(old->user_ns, old->fsgid);
851
852 kgid = make_kgid(old->user_ns, gid);
853 if (!gid_valid(kgid))
854 return old_fsgid;
d84f4f99
DH		 855
856 new = prepare_creds();
857 if (!new)
a29c33f4 858 return old_fsgid;
1da177e4 859
a29c33f4
EB		 860 if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) ||
861 gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) ||
c7b96acf 862 ns_capable(old->user_ns, CAP_SETGID)) {
a29c33f4
EB		 863 if (!gid_eq(kgid, old->fsgid)) {
864 new->fsgid = kgid;
d84f4f99 865 goto change_okay;
1da177e4 866 }
1da177e4 867 }
d84f4f99 868
d84f4f99
DH		 869 abort_creds(new);
870 return old_fsgid;
871
872change_okay:
873 commit_creds(new);
1da177e4
LT		 874 return old_fsgid;
875}
e530dca5
DB		 876
877SYSCALL_DEFINE1(setfsgid, gid_t, gid)
878{
879 return __sys_setfsgid(gid);
880}
2813893f 881#endif /* CONFIG_MULTIUSER */
1da177e4 882
4a22f166
SR		 883/**
884 * sys_getpid - return the thread group id of the current process
885 *
886 * Note, despite the name, this returns the tgid not the pid. The tgid and
887 * the pid are identical unless CLONE_THREAD was specified on clone() in
888 * which case the tgid is the same in all threads of the same group.
889 *
890 * This is SMP safe as current->tgid does not change.
891 */
892SYSCALL_DEFINE0(getpid)
893{
894 return task_tgid_vnr(current);
895}
896
897/* Thread ID - the internal kernel "pid" */
898SYSCALL_DEFINE0(gettid)
899{
900 return task_pid_vnr(current);
901}
902
903/*
904 * Accessing ->real_parent is not SMP-safe, it could
905 * change from under us. However, we can use a stale
906 * value of ->real_parent under rcu_read_lock(), see
907 * release_task()->call_rcu(delayed_put_task_struct).
908 */
909SYSCALL_DEFINE0(getppid)
910{
911 int pid;
912
913 rcu_read_lock();
914 pid = task_tgid_vnr(rcu_dereference(current->real_parent));
915 rcu_read_unlock();
916
917 return pid;
918}
919
920SYSCALL_DEFINE0(getuid)
921{
922 /* Only we change this so SMP safe */
923 return from_kuid_munged(current_user_ns(), current_uid());
924}
925
926SYSCALL_DEFINE0(geteuid)
927{
928 /* Only we change this so SMP safe */
929 return from_kuid_munged(current_user_ns(), current_euid());
930}
931
932SYSCALL_DEFINE0(getgid)
933{
934 /* Only we change this so SMP safe */
935 return from_kgid_munged(current_user_ns(), current_gid());
936}
937
938SYSCALL_DEFINE0(getegid)
939{
940 /* Only we change this so SMP safe */
941 return from_kgid_munged(current_user_ns(), current_egid());
942}
943
ca2406ed 944static void do_sys_times(struct tms *tms)
f06febc9 945{
5613fda9 946 u64 tgutime, tgstime, cutime, cstime;
f06febc9 947
e80d0a1a 948 thread_group_cputime_adjusted(current, &tgutime, &tgstime);
f06febc9
FM		 949 cutime = current->signal->cutime;
950 cstime = current->signal->cstime;
5613fda9
FW		 951 tms->tms_utime = nsec_to_clock_t(tgutime);
952 tms->tms_stime = nsec_to_clock_t(tgstime);
953 tms->tms_cutime = nsec_to_clock_t(cutime);
954 tms->tms_cstime = nsec_to_clock_t(cstime);
f06febc9
FM		 955}
956
58fd3aa2 957SYSCALL_DEFINE1(times, struct tms __user *, tbuf)
1da177e4 958{
1da177e4
LT		 959 if (tbuf) {
960 struct tms tmp;
f06febc9
FM		 961
962 do_sys_times(&tmp);
1da177e4
LT		 963 if (copy_to_user(tbuf, &tmp, sizeof(struct tms)))
964 return -EFAULT;
965 }
e3d5a27d 966 force_successful_syscall_return();
1da177e4
LT		 967 return (long) jiffies_64_to_clock_t(get_jiffies_64());
968}
969
ca2406ed
AV		 970#ifdef CONFIG_COMPAT
971static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
972{
973 return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
974}
975
976COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
977{
978 if (tbuf) {
979 struct tms tms;
980 struct compat_tms tmp;
981
982 do_sys_times(&tms);
983 /* Convert our struct tms to the compat version. */
984 tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
985 tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
986 tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
987 tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
988 if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
989 return -EFAULT;
990 }
991 force_successful_syscall_return();
992 return compat_jiffies_to_clock_t(jiffies);
993}
994#endif
995
1da177e4
LT		 996/*
997 * This needs some heavy checking ...
998 * I just haven't the stomach for it. I also don't fully
999 * understand sessions/pgrp etc. Let somebody who does explain it.
1000 *
1001 * OK, I think I have the protection semantics right.... this is really
1002 * only important on a multi-user system anyway, to make sure one user
1003 * can't send a signal to a process owned by another. -TYT, 12/12/91
1004 *
98611e4e 1005 * !PF_FORKNOEXEC check to conform completely to POSIX.
1da177e4 1006 */
b290ebe2 1007SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid)
1da177e4
LT		 1008{
1009 struct task_struct *p;
ee0acf90 1010 struct task_struct *group_leader = current->group_leader;
4e021306
ON		 1011 struct pid *pgrp;
1012 int err;
1da177e4
LT		 1013
1014 if (!pid)
b488893a 1015 pid = task_pid_vnr(group_leader);
1da177e4
LT		 1016 if (!pgid)
1017 pgid = pid;
1018 if (pgid < 0)
1019 return -EINVAL;
950eaaca 1020 rcu_read_lock();
1da177e4
LT		 1021
1022 /* From this point forward we keep holding onto the tasklist lock
1023 * so that our parent does not change from under us. -DaveM
1024 */
1025 write_lock_irq(&tasklist_lock);
1026
1027 err = -ESRCH;
4e021306 1028 p = find_task_by_vpid(pid);
1da177e4
LT		 1029 if (!p)
1030 goto out;
1031
1032 err = -EINVAL;
1033 if (!thread_group_leader(p))
1034 goto out;
1035
4e021306 1036 if (same_thread_group(p->real_parent, group_leader)) {
1da177e4 1037 err = -EPERM;
41487c65 1038 if (task_session(p) != task_session(group_leader))
1da177e4
LT		 1039 goto out;
1040 err = -EACCES;
98611e4e 1041 if (!(p->flags & PF_FORKNOEXEC))
1da177e4
LT		 1042 goto out;
1043 } else {
1044 err = -ESRCH;
ee0acf90 1045 if (p != group_leader)
1da177e4
LT		 1046 goto out;
1047 }
1048
1049 err = -EPERM;
1050 if (p->signal->leader)
1051 goto out;
1052
4e021306 1053 pgrp = task_pid(p);
1da177e4 1054 if (pgid != pid) {
b488893a 1055 struct task_struct *g;
1da177e4 1056
4e021306
ON		 1057 pgrp = find_vpid(pgid);
1058 g = pid_task(pgrp, PIDTYPE_PGID);
41487c65 1059 if (!g || task_session(g) != task_session(group_leader))
f020bc46 1060 goto out;
1da177e4
LT		 1061 }
1062
1da177e4
LT		 1063 err = security_task_setpgid(p, pgid);
1064 if (err)
1065 goto out;
1066
1b0f7ffd 1067 if (task_pgrp(p) != pgrp)
83beaf3c 1068 change_pid(p, PIDTYPE_PGID, pgrp);
1da177e4
LT		 1069
1070 err = 0;
1071out:
1072 /* All paths lead to here, thus we are safe. -DaveM */
1073 write_unlock_irq(&tasklist_lock);
950eaaca 1074 rcu_read_unlock();
1da177e4
LT		 1075 return err;
1076}
1077
192c5807 1078static int do_getpgid(pid_t pid)
1da177e4 1079{
12a3de0a
ON		 1080 struct task_struct *p;
1081 struct pid *grp;
1082 int retval;
1083
1084 rcu_read_lock();
756184b7 1085 if (!pid)
12a3de0a 1086 grp = task_pgrp(current);
756184b7 1087 else {
1da177e4 1088 retval = -ESRCH;
12a3de0a
ON		 1089 p = find_task_by_vpid(pid);
1090 if (!p)
1091 goto out;
1092 grp = task_pgrp(p);
1093 if (!grp)
1094 goto out;
1095
1096 retval = security_task_getpgid(p);
1097 if (retval)
1098 goto out;
1da177e4 1099 }
12a3de0a
ON		 1100 retval = pid_vnr(grp);
1101out:
1102 rcu_read_unlock();
1103 return retval;
1da177e4
LT		 1104}
1105
192c5807
DB		 1106SYSCALL_DEFINE1(getpgid, pid_t, pid)
1107{
1108 return do_getpgid(pid);
1109}
1110
1da177e4
LT		 1111#ifdef __ARCH_WANT_SYS_GETPGRP
1112
dbf040d9 1113SYSCALL_DEFINE0(getpgrp)
1da177e4 1114{
192c5807 1115 return do_getpgid(0);
1da177e4
LT		 1116}
1117
1118#endif
1119
dbf040d9 1120SYSCALL_DEFINE1(getsid, pid_t, pid)
1da177e4 1121{
1dd768c0
ON		 1122 struct task_struct *p;
1123 struct pid *sid;
1124 int retval;
1125
1126 rcu_read_lock();
756184b7 1127 if (!pid)
1dd768c0 1128 sid = task_session(current);
756184b7 1129 else {
1da177e4 1130 retval = -ESRCH;
1dd768c0
ON		 1131 p = find_task_by_vpid(pid);
1132 if (!p)
1133 goto out;
1134 sid = task_session(p);
1135 if (!sid)
1136 goto out;
1137
1138 retval = security_task_getsid(p);
1139 if (retval)
1140 goto out;
1da177e4 1141 }
1dd768c0
ON		 1142 retval = pid_vnr(sid);
1143out:
1144 rcu_read_unlock();
1145 return retval;
1da177e4
LT		 1146}
1147
81dabb46
ON		 1148static void set_special_pids(struct pid *pid)
1149{
1150 struct task_struct *curr = current->group_leader;
1151
1152 if (task_session(curr) != pid)
1153 change_pid(curr, PIDTYPE_SID, pid);
1154
1155 if (task_pgrp(curr) != pid)
1156 change_pid(curr, PIDTYPE_PGID, pid);
1157}
1158
e2aaa9f4 1159int ksys_setsid(void)
1da177e4 1160{
e19f247a 1161 struct task_struct *group_leader = current->group_leader;
e4cc0a9c
ON		 1162 struct pid *sid = task_pid(group_leader);
1163 pid_t session = pid_vnr(sid);
1da177e4
LT		 1164 int err = -EPERM;
1165
1da177e4 1166 write_lock_irq(&tasklist_lock);
390e2ff0
EB		 1167 /* Fail if I am already a session leader */
1168 if (group_leader->signal->leader)
1169 goto out;
1170
430c6231
ON		 1171 /* Fail if a process group id already exists that equals the
1172 * proposed session id.
390e2ff0 1173 */
6806aac6 1174 if (pid_task(sid, PIDTYPE_PGID))
1da177e4
LT		 1175 goto out;
1176
e19f247a 1177 group_leader->signal->leader = 1;
81dabb46 1178 set_special_pids(sid);
24ec839c 1179
9c9f4ded 1180 proc_clear_tty(group_leader);
24ec839c 1181
e4cc0a9c 1182 err = session;
1da177e4
LT		 1183out:
1184 write_unlock_irq(&tasklist_lock);
5091faa4 1185 if (err > 0) {
0d0df599 1186 proc_sid_connector(group_leader);
5091faa4
MG		 1187 sched_autogroup_create_attach(group_leader);
1188 }
1da177e4
LT		 1189 return err;
1190}
1191
e2aaa9f4
DB		 1192SYSCALL_DEFINE0(setsid)
1193{
1194 return ksys_setsid();
1195}
1196
1da177e4
LT		 1197DECLARE_RWSEM(uts_sem);
1198
e28cbf22
CH		 1199#ifdef COMPAT_UTS_MACHINE
1200#define override_architecture(name) \
46da2766 1201 (personality(current->personality) == PER_LINUX32 && \
e28cbf22
CH		 1202 copy_to_user(name->machine, COMPAT_UTS_MACHINE, \
1203 sizeof(COMPAT_UTS_MACHINE)))
1204#else
1205#define override_architecture(name) 0
1206#endif
1207
be27425d
AK		 1208/*
1209 * Work around broken programs that cannot handle "Linux 3.0".
1210 * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
b7285b42
JN		 1211 * And we map 4.x and later versions to 2.6.60+x, so 4.0/5.0/6.0/... would be
1212 * 2.6.60.
be27425d 1213 */
2702b152 1214static int override_release(char __user *release, size_t len)
be27425d
AK		 1215{
1216 int ret = 0;
be27425d
AK		 1217
1218 if (current->personality & UNAME26) {
2702b152
KC		 1219 const char *rest = UTS_RELEASE;
1220 char buf[65] = { 0 };
be27425d
AK		 1221 int ndots = 0;
1222 unsigned v;
2702b152 1223 size_t copy;
be27425d
AK		 1224
1225 while (*rest) {
1226 if (*rest == '.' && ++ndots >= 3)
1227 break;
1228 if (!isdigit(*rest) && *rest != '.')
1229 break;
1230 rest++;
1231 }
39afb5ee 1232 v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 60;
31fd84b9 1233 copy = clamp_t(size_t, len, 1, sizeof(buf));
2702b152
KC		 1234 copy = scnprintf(buf, copy, "2.6.%u%s", v, rest);
1235 ret = copy_to_user(release, buf, copy + 1);
be27425d
AK		 1236 }
1237 return ret;
1238}
1239
e48fbb69 1240SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
1da177e4 1241{
42a0cc34 1242 struct new_utsname tmp;
1da177e4
LT		 1243
1244 down_read(&uts_sem);
42a0cc34 1245 memcpy(&tmp, utsname(), sizeof(tmp));
1da177e4 1246 up_read(&uts_sem);
42a0cc34
JH		 1247 if (copy_to_user(name, &tmp, sizeof(tmp)))
1248 return -EFAULT;
e28cbf22 1249
42a0cc34
JH		 1250 if (override_release(name->release, sizeof(name->release)))
1251 return -EFAULT;
1252 if (override_architecture(name))
1253 return -EFAULT;
1254 return 0;
1da177e4
LT		 1255}
1256
5cacdb4a
CH		 1257#ifdef __ARCH_WANT_SYS_OLD_UNAME
1258/*
1259 * Old cruft
1260 */
1261SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
1262{
42a0cc34 1263 struct old_utsname tmp;
5cacdb4a
CH		 1264
1265 if (!name)
1266 return -EFAULT;
1267
1268 down_read(&uts_sem);
42a0cc34 1269 memcpy(&tmp, utsname(), sizeof(tmp));
5cacdb4a 1270 up_read(&uts_sem);
42a0cc34
JH		 1271 if (copy_to_user(name, &tmp, sizeof(tmp)))
1272 return -EFAULT;
5cacdb4a 1273
42a0cc34
JH		 1274 if (override_release(name->release, sizeof(name->release)))
1275 return -EFAULT;
1276 if (override_architecture(name))
1277 return -EFAULT;
1278 return 0;
5cacdb4a
CH		 1279}
1280
1281SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
1282{
5e1aada0 1283 struct oldold_utsname tmp;
5cacdb4a
CH		 1284
1285 if (!name)
1286 return -EFAULT;
5cacdb4a 1287
5e1aada0
JP		 1288 memset(&tmp, 0, sizeof(tmp));
1289
5cacdb4a 1290 down_read(&uts_sem);
42a0cc34
JH		 1291 memcpy(&tmp.sysname, &utsname()->sysname, __OLD_UTS_LEN);
1292 memcpy(&tmp.nodename, &utsname()->nodename, __OLD_UTS_LEN);
1293 memcpy(&tmp.release, &utsname()->release, __OLD_UTS_LEN);
1294 memcpy(&tmp.version, &utsname()->version, __OLD_UTS_LEN);
1295 memcpy(&tmp.machine, &utsname()->machine, __OLD_UTS_LEN);
5cacdb4a 1296 up_read(&uts_sem);
42a0cc34
JH		 1297 if (copy_to_user(name, &tmp, sizeof(tmp)))
1298 return -EFAULT;
5cacdb4a 1299
42a0cc34
JH		 1300 if (override_architecture(name))
1301 return -EFAULT;
1302 if (override_release(name->release, sizeof(name->release)))
1303 return -EFAULT;
1304 return 0;
5cacdb4a
CH		 1305}
1306#endif
1307
5a8a82b1 1308SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
1da177e4
LT		 1309{
1310 int errno;
1311 char tmp[__NEW_UTS_LEN];
1312
bb96a6f5 1313 if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1da177e4 1314 return -EPERM;
fc832ad3 1315
1da177e4
LT		 1316 if (len < 0 || len > __NEW_UTS_LEN)
1317 return -EINVAL;
1da177e4
LT		 1318 errno = -EFAULT;
1319 if (!copy_from_user(tmp, name, len)) {
42a0cc34 1320 struct new_utsname *u;
9679e4dd 1321
42a0cc34
JH		 1322 down_write(&uts_sem);
1323 u = utsname();
9679e4dd
AM		 1324 memcpy(u->nodename, tmp, len);
1325 memset(u->nodename + len, 0, sizeof(u->nodename) - len);
1da177e4 1326 errno = 0;
499eea6b 1327 uts_proc_notify(UTS_PROC_HOSTNAME);
42a0cc34 1328 up_write(&uts_sem);
1da177e4 1329 }
1da177e4
LT		 1330 return errno;
1331}
1332
1333#ifdef __ARCH_WANT_SYS_GETHOSTNAME
1334
5a8a82b1 1335SYSCALL_DEFINE2(gethostname, char __user *, name, int, len)
1da177e4 1336{
42a0cc34 1337 int i;
9679e4dd 1338 struct new_utsname *u;
42a0cc34 1339 char tmp[__NEW_UTS_LEN + 1];
1da177e4
LT		 1340
1341 if (len < 0)
1342 return -EINVAL;
1343 down_read(&uts_sem);
9679e4dd
AM		 1344 u = utsname();
1345 i = 1 + strlen(u->nodename);
1da177e4
LT		 1346 if (i > len)
1347 i = len;
42a0cc34 1348 memcpy(tmp, u->nodename, i);
1da177e4 1349 up_read(&uts_sem);
42a0cc34
JH		 1350 if (copy_to_user(name, tmp, i))
1351 return -EFAULT;
1352 return 0;
1da177e4
LT		 1353}
1354
1355#endif
1356
1357/*
1358 * Only setdomainname; getdomainname can be implemented by calling
1359 * uname()
1360 */
5a8a82b1 1361SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len)
1da177e4
LT		 1362{
1363 int errno;
1364 char tmp[__NEW_UTS_LEN];
1365
fc832ad3 1366 if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1da177e4
LT		 1367 return -EPERM;
1368 if (len < 0 || len > __NEW_UTS_LEN)
1369 return -EINVAL;
1370
1da177e4
LT		 1371 errno = -EFAULT;
1372 if (!copy_from_user(tmp, name, len)) {
42a0cc34 1373 struct new_utsname *u;
9679e4dd 1374
42a0cc34
JH		 1375 down_write(&uts_sem);
1376 u = utsname();
9679e4dd
AM		 1377 memcpy(u->domainname, tmp, len);
1378 memset(u->domainname + len, 0, sizeof(u->domainname) - len);
1da177e4 1379 errno = 0;
499eea6b 1380 uts_proc_notify(UTS_PROC_DOMAINNAME);
42a0cc34 1381 up_write(&uts_sem);
1da177e4 1382 }
1da177e4
LT		 1383 return errno;
1384}
1385
e48fbb69 1386SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1da177e4 1387{
b9518345
JS		 1388 struct rlimit value;
1389 int ret;
1390
1391 ret = do_prlimit(current, resource, NULL, &value);
1392 if (!ret)
1393 ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0;
1394
1395 return ret;
1da177e4
LT		 1396}
1397
d9e968cb
AV		 1398#ifdef CONFIG_COMPAT
1399
1400COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
1401 struct compat_rlimit __user *, rlim)
1402{
1403 struct rlimit r;
1404 struct compat_rlimit r32;
1405
1406 if (copy_from_user(&r32, rlim, sizeof(struct compat_rlimit)))
1407 return -EFAULT;
1408
1409 if (r32.rlim_cur == COMPAT_RLIM_INFINITY)
1410 r.rlim_cur = RLIM_INFINITY;
1411 else
1412 r.rlim_cur = r32.rlim_cur;
1413 if (r32.rlim_max == COMPAT_RLIM_INFINITY)
1414 r.rlim_max = RLIM_INFINITY;
1415 else
1416 r.rlim_max = r32.rlim_max;
1417 return do_prlimit(current, resource, &r, NULL);
1418}
1419
1420COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
1421 struct compat_rlimit __user *, rlim)
1422{
1423 struct rlimit r;
1424 int ret;
1425
1426 ret = do_prlimit(current, resource, NULL, &r);
1427 if (!ret) {
58c7ffc0 1428 struct compat_rlimit r32;
d9e968cb
AV		 1429 if (r.rlim_cur > COMPAT_RLIM_INFINITY)
1430 r32.rlim_cur = COMPAT_RLIM_INFINITY;
1431 else
1432 r32.rlim_cur = r.rlim_cur;
1433 if (r.rlim_max > COMPAT_RLIM_INFINITY)
1434 r32.rlim_max = COMPAT_RLIM_INFINITY;
1435 else
1436 r32.rlim_max = r.rlim_max;
1437
1438 if (copy_to_user(rlim, &r32, sizeof(struct compat_rlimit)))
1439 return -EFAULT;
1440 }
1441 return ret;
1442}
1443
1444#endif
1445
1da177e4
LT		 1446#ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
1447
1448/*
1449 * Back compatibility for getrlimit. Needed for some apps.
1450 */
e48fbb69
HC		 1451SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1452 struct rlimit __user *, rlim)
1da177e4
LT		 1453{
1454 struct rlimit x;
1455 if (resource >= RLIM_NLIMITS)
1456 return -EINVAL;
1457
23d6aef7 1458 resource = array_index_nospec(resource, RLIM_NLIMITS);
1da177e4
LT		 1459 task_lock(current->group_leader);
1460 x = current->signal->rlim[resource];
1461 task_unlock(current->group_leader);
756184b7 1462 if (x.rlim_cur > 0x7FFFFFFF)
1da177e4 1463 x.rlim_cur = 0x7FFFFFFF;
756184b7 1464 if (x.rlim_max > 0x7FFFFFFF)
1da177e4 1465 x.rlim_max = 0x7FFFFFFF;
ec94fc3d 1466 return copy_to_user(rlim, &x, sizeof(x)) ? -EFAULT : 0;
1da177e4
LT		 1467}
1468
613763a1
AV		 1469#ifdef CONFIG_COMPAT
1470COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1471 struct compat_rlimit __user *, rlim)
1472{
1473 struct rlimit r;
1474
1475 if (resource >= RLIM_NLIMITS)
1476 return -EINVAL;
1477
23d6aef7 1478 resource = array_index_nospec(resource, RLIM_NLIMITS);
613763a1
AV		 1479 task_lock(current->group_leader);
1480 r = current->signal->rlim[resource];
1481 task_unlock(current->group_leader);
1482 if (r.rlim_cur > 0x7FFFFFFF)
1483 r.rlim_cur = 0x7FFFFFFF;
1484 if (r.rlim_max > 0x7FFFFFFF)
1485 r.rlim_max = 0x7FFFFFFF;
1486
1487 if (put_user(r.rlim_cur, &rlim->rlim_cur) ||
1488 put_user(r.rlim_max, &rlim->rlim_max))
1489 return -EFAULT;
1490 return 0;
1491}
1492#endif
1493
1da177e4
LT		 1494#endif
1495
c022a0ac
JS		 1496static inline bool rlim64_is_infinity(__u64 rlim64)
1497{
1498#if BITS_PER_LONG < 64
1499 return rlim64 >= ULONG_MAX;
1500#else
1501 return rlim64 == RLIM64_INFINITY;
1502#endif
1503}
1504
1505static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64)
1506{
1507 if (rlim->rlim_cur == RLIM_INFINITY)
1508 rlim64->rlim_cur = RLIM64_INFINITY;
1509 else
1510 rlim64->rlim_cur = rlim->rlim_cur;
1511 if (rlim->rlim_max == RLIM_INFINITY)
1512 rlim64->rlim_max = RLIM64_INFINITY;
1513 else
1514 rlim64->rlim_max = rlim->rlim_max;
1515}
1516
1517static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim)
1518{
1519 if (rlim64_is_infinity(rlim64->rlim_cur))
1520 rlim->rlim_cur = RLIM_INFINITY;
1521 else
1522 rlim->rlim_cur = (unsigned long)rlim64->rlim_cur;
1523 if (rlim64_is_infinity(rlim64->rlim_max))
1524 rlim->rlim_max = RLIM_INFINITY;
1525 else
1526 rlim->rlim_max = (unsigned long)rlim64->rlim_max;
1527}
1528
1c1e618d 1529/* make sure you are allowed to change @tsk limits before calling this */
5b41535a
JS		 1530int do_prlimit(struct task_struct *tsk, unsigned int resource,
1531 struct rlimit *new_rlim, struct rlimit *old_rlim)
1da177e4 1532{
5b41535a 1533 struct rlimit *rlim;
86f162f4 1534 int retval = 0;
1da177e4
LT		 1535
1536 if (resource >= RLIM_NLIMITS)
1537 return -EINVAL;
5b41535a
JS		 1538 if (new_rlim) {
1539 if (new_rlim->rlim_cur > new_rlim->rlim_max)
1540 return -EINVAL;
1541 if (resource == RLIMIT_NOFILE &&
1542 new_rlim->rlim_max > sysctl_nr_open)
1543 return -EPERM;
1544 }
1da177e4 1545
1c1e618d
JS		 1546 /* protect tsk->signal and tsk->sighand from disappearing */
1547 read_lock(&tasklist_lock);
1548 if (!tsk->sighand) {
1549 retval = -ESRCH;
1550 goto out;
1551 }
1552
5b41535a 1553 rlim = tsk->signal->rlim + resource;
86f162f4 1554 task_lock(tsk->group_leader);
5b41535a 1555 if (new_rlim) {
fc832ad3
SH		 1556 /* Keep the capable check against init_user_ns until
1557 cgroups can contain all limits */
5b41535a
JS		 1558 if (new_rlim->rlim_max > rlim->rlim_max &&
1559 !capable(CAP_SYS_RESOURCE))
1560 retval = -EPERM;
1561 if (!retval)
cad4ea54 1562 retval = security_task_setrlimit(tsk, resource, new_rlim);
5b41535a
JS		 1563 }
1564 if (!retval) {
1565 if (old_rlim)
1566 *old_rlim = *rlim;
1567 if (new_rlim)
1568 *rlim = *new_rlim;
9926e4c7 1569 }
7855c35d 1570 task_unlock(tsk->group_leader);
1da177e4 1571
d3561f78 1572 /*
24db4dd9
TG		 1573 * RLIMIT_CPU handling. Arm the posix CPU timer if the limit is not
1574 * infite. In case of RLIM_INFINITY the posix CPU timer code
1575 * ignores the rlimit.
d3561f78 1576 */
5b41535a 1577 if (!retval && new_rlim && resource == RLIMIT_CPU &&
baa73d9e
NP		 1578 new_rlim->rlim_cur != RLIM_INFINITY &&
1579 IS_ENABLED(CONFIG_POSIX_TIMERS))
5b41535a 1580 update_rlimit_cpu(tsk, new_rlim->rlim_cur);
ec9e16ba 1581out:
1c1e618d 1582 read_unlock(&tasklist_lock);
2fb9d268 1583 return retval;
1da177e4
LT		 1584}
1585
c022a0ac 1586/* rcu lock must be held */
791ec491
SS		 1587static int check_prlimit_permission(struct task_struct *task,
1588 unsigned int flags)
c022a0ac
JS		 1589{
1590 const struct cred *cred = current_cred(), *tcred;
791ec491 1591 bool id_match;
c022a0ac 1592
fc832ad3
SH		 1593 if (current == task)
1594 return 0;
c022a0ac 1595
fc832ad3 1596 tcred = __task_cred(task);
791ec491
SS		 1597 id_match = (uid_eq(cred->uid, tcred->euid) &&
1598 uid_eq(cred->uid, tcred->suid) &&
1599 uid_eq(cred->uid, tcred->uid) &&
1600 gid_eq(cred->gid, tcred->egid) &&
1601 gid_eq(cred->gid, tcred->sgid) &&
1602 gid_eq(cred->gid, tcred->gid));
1603 if (!id_match && !ns_capable(tcred->user_ns, CAP_SYS_RESOURCE))
1604 return -EPERM;
fc832ad3 1605
791ec491 1606 return security_task_prlimit(cred, tcred, flags);
c022a0ac
JS		 1607}
1608
1609SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource,
1610 const struct rlimit64 __user *, new_rlim,
1611 struct rlimit64 __user *, old_rlim)
1612{
1613 struct rlimit64 old64, new64;
1614 struct rlimit old, new;
1615 struct task_struct *tsk;
791ec491 1616 unsigned int checkflags = 0;
c022a0ac
JS		 1617 int ret;
1618
791ec491
SS		 1619 if (old_rlim)
1620 checkflags |= LSM_PRLIMIT_READ;
1621
c022a0ac
JS		 1622 if (new_rlim) {
1623 if (copy_from_user(&new64, new_rlim, sizeof(new64)))
1624 return -EFAULT;
1625 rlim64_to_rlim(&new64, &new);
791ec491 1626 checkflags |= LSM_PRLIMIT_WRITE;
c022a0ac
JS		 1627 }
1628
1629 rcu_read_lock();
1630 tsk = pid ? find_task_by_vpid(pid) : current;
1631 if (!tsk) {
1632 rcu_read_unlock();
1633 return -ESRCH;
1634 }
791ec491 1635 ret = check_prlimit_permission(tsk, checkflags);
c022a0ac
JS		 1636 if (ret) {
1637 rcu_read_unlock();
1638 return ret;
1639 }
1640 get_task_struct(tsk);
1641 rcu_read_unlock();
1642
1643 ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL,
1644 old_rlim ? &old : NULL);
1645
1646 if (!ret && old_rlim) {
1647 rlim_to_rlim64(&old, &old64);
1648 if (copy_to_user(old_rlim, &old64, sizeof(old64)))
1649 ret = -EFAULT;
1650 }
1651
1652 put_task_struct(tsk);
1653 return ret;
1654}
1655
7855c35d
JS		 1656SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1657{
1658 struct rlimit new_rlim;
1659
1660 if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
1661 return -EFAULT;
5b41535a 1662 return do_prlimit(current, resource, &new_rlim, NULL);
7855c35d
JS		 1663}
1664
1da177e4
LT		 1665/*
1666 * It would make sense to put struct rusage in the task_struct,
1667 * except that would make the task_struct be *really big*. After
1668 * task_struct gets moved into malloc'ed memory, it would
1669 * make sense to do this. It will make moving the rest of the information
1670 * a lot simpler! (Which we're not doing right now because we're not
1671 * measuring them yet).
1672 *
1da177e4
LT		 1673 * When sampling multiple threads for RUSAGE_SELF, under SMP we might have
1674 * races with threads incrementing their own counters. But since word
1675 * reads are atomic, we either get new values or old values and we don't
1676 * care which for the sums. We always take the siglock to protect reading
1677 * the c* fields from p->signal from races with exit.c updating those
1678 * fields when reaping, so a sample either gets all the additions of a
1679 * given child after it's reaped, or none so this sample is before reaping.
2dd0ebcd 1680 *
de047c1b
RT		 1681 * Locking:
1682 * We need to take the siglock for CHILDEREN, SELF and BOTH
1683 * for the cases current multithreaded, non-current single threaded
1684 * non-current multithreaded. Thread traversal is now safe with
1685 * the siglock held.
1686 * Strictly speaking, we donot need to take the siglock if we are current and
1687 * single threaded, as no one else can take our signal_struct away, no one
1688 * else can reap the children to update signal->c* counters, and no one else
1689 * can race with the signal-> fields. If we do not take any lock, the
1690 * signal-> fields could be read out of order while another thread was just
1691 * exiting. So we should place a read memory barrier when we avoid the lock.
1692 * On the writer side, write memory barrier is implied in __exit_signal
1693 * as __exit_signal releases the siglock spinlock after updating the signal->
1694 * fields. But we don't do this yet to keep things simple.
2dd0ebcd 1695 *
1da177e4
LT		 1696 */
1697
f06febc9 1698static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r)
679c9cd4 1699{
679c9cd4
SK		 1700 r->ru_nvcsw += t->nvcsw;
1701 r->ru_nivcsw += t->nivcsw;
1702 r->ru_minflt += t->min_flt;
1703 r->ru_majflt += t->maj_flt;
1704 r->ru_inblock += task_io_get_inblock(t);
1705 r->ru_oublock += task_io_get_oublock(t);
1706}
1707
ce72a16f 1708void getrusage(struct task_struct *p, int who, struct rusage *r)
1da177e4
LT		 1709{
1710 struct task_struct *t;
1711 unsigned long flags;
5613fda9 1712 u64 tgutime, tgstime, utime, stime;
1f10206c 1713 unsigned long maxrss = 0;
1da177e4 1714
ec94fc3d 1715 memset((char *)r, 0, sizeof (*r));
64861634 1716 utime = stime = 0;
1da177e4 1717
679c9cd4 1718 if (who == RUSAGE_THREAD) {
e80d0a1a 1719 task_cputime_adjusted(current, &utime, &stime);
f06febc9 1720 accumulate_thread_rusage(p, r);
1f10206c 1721 maxrss = p->signal->maxrss;
679c9cd4
SK		 1722 goto out;
1723 }
1724
d6cf723a 1725 if (!lock_task_sighand(p, &flags))
de047c1b 1726 return;
0f59cc4a 1727
1da177e4 1728 switch (who) {
ec94fc3d 1729 case RUSAGE_BOTH:
1730 case RUSAGE_CHILDREN:
1731 utime = p->signal->cutime;
1732 stime = p->signal->cstime;
1733 r->ru_nvcsw = p->signal->cnvcsw;
1734 r->ru_nivcsw = p->signal->cnivcsw;
1735 r->ru_minflt = p->signal->cmin_flt;
1736 r->ru_majflt = p->signal->cmaj_flt;
1737 r->ru_inblock = p->signal->cinblock;
1738 r->ru_oublock = p->signal->coublock;
1739 maxrss = p->signal->cmaxrss;
1740
1741 if (who == RUSAGE_CHILDREN)
1da177e4 1742 break;
21f63a5d 1743 /* fall through */
0f59cc4a 1744
ec94fc3d 1745 case RUSAGE_SELF:
1746 thread_group_cputime_adjusted(p, &tgutime, &tgstime);
1747 utime += tgutime;
1748 stime += tgstime;
1749 r->ru_nvcsw += p->signal->nvcsw;
1750 r->ru_nivcsw += p->signal->nivcsw;
1751 r->ru_minflt += p->signal->min_flt;
1752 r->ru_majflt += p->signal->maj_flt;
1753 r->ru_inblock += p->signal->inblock;
1754 r->ru_oublock += p->signal->oublock;
1755 if (maxrss < p->signal->maxrss)
1756 maxrss = p->signal->maxrss;
1757 t = p;
1758 do {
1759 accumulate_thread_rusage(t, r);
1760 } while_each_thread(p, t);
1761 break;
1762
1763 default:
1764 BUG();
1da177e4 1765 }
de047c1b 1766 unlock_task_sighand(p, &flags);
de047c1b 1767
679c9cd4 1768out:
bdd565f8
AB		 1769 r->ru_utime = ns_to_kernel_old_timeval(utime);
1770 r->ru_stime = ns_to_kernel_old_timeval(stime);
1f10206c
JP		 1771
1772 if (who != RUSAGE_CHILDREN) {
1773 struct mm_struct *mm = get_task_mm(p);
ec94fc3d 1774
1f10206c
JP		 1775 if (mm) {
1776 setmax_mm_hiwater_rss(&maxrss, mm);
1777 mmput(mm);
1778 }
1779 }
1780 r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */
1da177e4
LT		 1781}
1782
ce72a16f 1783SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru)
1da177e4
LT		 1784{
1785 struct rusage r;
ec94fc3d 1786
679c9cd4
SK		 1787 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1788 who != RUSAGE_THREAD)
1da177e4 1789 return -EINVAL;
ce72a16f
AV		 1790
1791 getrusage(current, who, &r);
1792 return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
1da177e4
LT		 1793}
1794
8d2d5c4a
AV		 1795#ifdef CONFIG_COMPAT
1796COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru)
1797{
1798 struct rusage r;
1799
1800 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1801 who != RUSAGE_THREAD)
1802 return -EINVAL;
1803
ce72a16f 1804 getrusage(current, who, &r);
8d2d5c4a
AV		 1805 return put_compat_rusage(&r, ru);
1806}
1807#endif
1808
e48fbb69 1809SYSCALL_DEFINE1(umask, int, mask)
1da177e4
LT		 1810{
1811 mask = xchg(&current->fs->umask, mask & S_IRWXUGO);
1812 return mask;
1813}
3b7391de 1814
6e399cd1 1815static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
b32dfe37 1816{
2903ff01 1817 struct fd exe;
6e399cd1 1818 struct file *old_exe, *exe_file;
496ad9aa 1819 struct inode *inode;
2903ff01 1820 int err;
b32dfe37 1821
2903ff01
AV		 1822 exe = fdget(fd);
1823 if (!exe.file)
b32dfe37
CG		 1824 return -EBADF;
1825
496ad9aa 1826 inode = file_inode(exe.file);
b32dfe37
CG		 1827
1828 /*
1829 * Because the original mm->exe_file points to executable file, make
1830 * sure that this one is executable as well, to avoid breaking an
1831 * overall picture.
1832 */
1833 err = -EACCES;
90f8572b 1834 if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path))
b32dfe37
CG		 1835 goto exit;
1836
496ad9aa 1837 err = inode_permission(inode, MAY_EXEC);
b32dfe37
CG		 1838 if (err)
1839 goto exit;
1840
bafb282d 1841 /*
4229fb1d 1842 * Forbid mm->exe_file change if old file still mapped.
bafb282d 1843 */
6e399cd1 1844 exe_file = get_mm_exe_file(mm);
bafb282d 1845 err = -EBUSY;
6e399cd1 1846 if (exe_file) {
4229fb1d
KK		 1847 struct vm_area_struct *vma;
1848
6e399cd1
DB		 1849 down_read(&mm->mmap_sem);
1850 for (vma = mm->mmap; vma; vma = vma->vm_next) {
1851 if (!vma->vm_file)
1852 continue;
1853 if (path_equal(&vma->vm_file->f_path,
1854 &exe_file->f_path))
1855 goto exit_err;
1856 }
1857
1858 up_read(&mm->mmap_sem);
1859 fput(exe_file);
bafb282d
KK		 1860 }
1861
4229fb1d 1862 err = 0;
6e399cd1
DB		 1863 /* set the new file, lockless */
1864 get_file(exe.file);
1865 old_exe = xchg(&mm->exe_file, exe.file);
1866 if (old_exe)
1867 fput(old_exe);
b32dfe37 1868exit:
2903ff01 1869 fdput(exe);
b32dfe37 1870 return err;
6e399cd1
DB		 1871exit_err:
1872 up_read(&mm->mmap_sem);
1873 fput(exe_file);
1874 goto exit;
b32dfe37
CG		 1875}
1876
f606b77f 1877/*
11bbd8b4
MK		 1878 * Check arithmetic relations of passed addresses.
1879 *
f606b77f
CG		 1880 * WARNING: we don't require any capability here so be very careful
1881 * in what is allowed for modification from userspace.
1882 */
11bbd8b4 1883static int validate_prctl_map_addr(struct prctl_mm_map *prctl_map)
f606b77f
CG		 1884{
1885 unsigned long mmap_max_addr = TASK_SIZE;
f606b77f
CG		 1886 int error = -EINVAL, i;
1887
1888 static const unsigned char offsets[] = {
1889 offsetof(struct prctl_mm_map, start_code),
1890 offsetof(struct prctl_mm_map, end_code),
1891 offsetof(struct prctl_mm_map, start_data),
1892 offsetof(struct prctl_mm_map, end_data),
1893 offsetof(struct prctl_mm_map, start_brk),
1894 offsetof(struct prctl_mm_map, brk),
1895 offsetof(struct prctl_mm_map, start_stack),
1896 offsetof(struct prctl_mm_map, arg_start),
1897 offsetof(struct prctl_mm_map, arg_end),
1898 offsetof(struct prctl_mm_map, env_start),
1899 offsetof(struct prctl_mm_map, env_end),
1900 };
1901
1902 /*
1903 * Make sure the members are not somewhere outside
1904 * of allowed address space.
1905 */
1906 for (i = 0; i < ARRAY_SIZE(offsets); i++) {
1907 u64 val = *(u64 *)((char *)prctl_map + offsets[i]);
1908
1909 if ((unsigned long)val >= mmap_max_addr ||
1910 (unsigned long)val < mmap_min_addr)
1911 goto out;
1912 }
1913
1914 /*
1915 * Make sure the pairs are ordered.
1916 */
1917#define __prctl_check_order(__m1, __op, __m2) \
1918 ((unsigned long)prctl_map->__m1 __op \
1919 (unsigned long)prctl_map->__m2) ? 0 : -EINVAL
1920 error = __prctl_check_order(start_code, <, end_code);
a9e73998 1921 error |= __prctl_check_order(start_data,<=, end_data);
f606b77f
CG		 1922 error |= __prctl_check_order(start_brk, <=, brk);
1923 error |= __prctl_check_order(arg_start, <=, arg_end);
1924 error |= __prctl_check_order(env_start, <=, env_end);
1925 if (error)
1926 goto out;
1927#undef __prctl_check_order
1928
1929 error = -EINVAL;
1930
1931 /*
1932 * @brk should be after @end_data in traditional maps.
1933 */
1934 if (prctl_map->start_brk <= prctl_map->end_data ||
1935 prctl_map->brk <= prctl_map->end_data)
1936 goto out;
1937
1938 /*
1939 * Neither we should allow to override limits if they set.
1940 */
1941 if (check_data_rlimit(rlimit(RLIMIT_DATA), prctl_map->brk,
1942 prctl_map->start_brk, prctl_map->end_data,
1943 prctl_map->start_data))
1944 goto out;
1945
f606b77f
CG		 1946 error = 0;
1947out:
1948 return error;
1949}
1950
4a00e9df 1951#ifdef CONFIG_CHECKPOINT_RESTORE
f606b77f
CG		 1952static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size)
1953{
1954 struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, };
1955 unsigned long user_auxv[AT_VECTOR_SIZE];
1956 struct mm_struct *mm = current->mm;
1957 int error;
1958
1959 BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
1960 BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256);
1961
1962 if (opt == PR_SET_MM_MAP_SIZE)
1963 return put_user((unsigned int)sizeof(prctl_map),
1964 (unsigned int __user *)addr);
1965
1966 if (data_size != sizeof(prctl_map))
1967 return -EINVAL;
1968
1969 if (copy_from_user(&prctl_map, addr, sizeof(prctl_map)))
1970 return -EFAULT;
1971
11bbd8b4 1972 error = validate_prctl_map_addr(&prctl_map);
f606b77f
CG		 1973 if (error)
1974 return error;
1975
1976 if (prctl_map.auxv_size) {
11bbd8b4
MK		 1977 /*
1978 * Someone is trying to cheat the auxv vector.
1979 */
1980 if (!prctl_map.auxv ||
1981 prctl_map.auxv_size > sizeof(mm->saved_auxv))
1982 return -EINVAL;
1983
f606b77f
CG		 1984 memset(user_auxv, 0, sizeof(user_auxv));
1985 if (copy_from_user(user_auxv,
1986 (const void __user *)prctl_map.auxv,
1987 prctl_map.auxv_size))
1988 return -EFAULT;
1989
1990 /* Last entry must be AT_NULL as specification requires */
1991 user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL;
1992 user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL;
1993 }
1994
ddf1d398 1995 if (prctl_map.exe_fd != (u32)-1) {
11bbd8b4
MK		 1996 /*
1997 * Make sure the caller has the rights to
1998 * change /proc/pid/exe link: only local sys admin should
1999 * be allowed to.
2000 */
2001 if (!ns_capable(current_user_ns(), CAP_SYS_ADMIN))
2002 return -EINVAL;
2003
6e399cd1 2004 error = prctl_set_mm_exe_file(mm, prctl_map.exe_fd);
ddf1d398
MG		 2005 if (error)
2006 return error;
2007 }
2008
88aa7cc6
YS		 2009 /*
2010 * arg_lock protects concurent updates but we still need mmap_sem for
2011 * read to exclude races with sys_brk.
2012 */
2013 down_read(&mm->mmap_sem);
f606b77f
CG		 2014
2015 /*
2016 * We don't validate if these members are pointing to
2017 * real present VMAs because application may have correspond
2018 * VMAs already unmapped and kernel uses these members for statistics
2019 * output in procfs mostly, except
2020 *
2021 * - @start_brk/@brk which are used in do_brk but kernel lookups
2022 * for VMAs when updating these memvers so anything wrong written
2023 * here cause kernel to swear at userspace program but won't lead
2024 * to any problem in kernel itself
2025 */
2026
88aa7cc6 2027 spin_lock(&mm->arg_lock);
f606b77f
CG		 2028 mm->start_code = prctl_map.start_code;
2029 mm->end_code = prctl_map.end_code;
2030 mm->start_data = prctl_map.start_data;
2031 mm->end_data = prctl_map.end_data;
2032 mm->start_brk = prctl_map.start_brk;
2033 mm->brk = prctl_map.brk;
2034 mm->start_stack = prctl_map.start_stack;
2035 mm->arg_start = prctl_map.arg_start;
2036 mm->arg_end = prctl_map.arg_end;
2037 mm->env_start = prctl_map.env_start;
2038 mm->env_end = prctl_map.env_end;
88aa7cc6 2039 spin_unlock(&mm->arg_lock);
f606b77f
CG		 2040
2041 /*
2042 * Note this update of @saved_auxv is lockless thus
2043 * if someone reads this member in procfs while we're
2044 * updating -- it may get partly updated results. It's
2045 * known and acceptable trade off: we leave it as is to
2046 * not introduce additional locks here making the kernel
2047 * more complex.
2048 */
2049 if (prctl_map.auxv_size)
2050 memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv));
2051
88aa7cc6 2052 up_read(&mm->mmap_sem);
ddf1d398 2053 return 0;
f606b77f
CG		 2054}
2055#endif /* CONFIG_CHECKPOINT_RESTORE */
2056
4a00e9df
AD		 2057static int prctl_set_auxv(struct mm_struct *mm, unsigned long addr,
2058 unsigned long len)
2059{
2060 /*
2061 * This doesn't move the auxiliary vector itself since it's pinned to
2062 * mm_struct, but it permits filling the vector with new values. It's
2063 * up to the caller to provide sane values here, otherwise userspace
2064 * tools which use this vector might be unhappy.
2065 */
2066 unsigned long user_auxv[AT_VECTOR_SIZE];
2067
2068 if (len > sizeof(user_auxv))
2069 return -EINVAL;
2070
2071 if (copy_from_user(user_auxv, (const void __user *)addr, len))
2072 return -EFAULT;
2073
2074 /* Make sure the last entry is always AT_NULL */
2075 user_auxv[AT_VECTOR_SIZE - 2] = 0;
2076 user_auxv[AT_VECTOR_SIZE - 1] = 0;
2077
2078 BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
2079
2080 task_lock(current);
2081 memcpy(mm->saved_auxv, user_auxv, len);
2082 task_unlock(current);
2083
2084 return 0;
2085}
2086
028ee4be
CG		 2087static int prctl_set_mm(int opt, unsigned long addr,
2088 unsigned long arg4, unsigned long arg5)
2089{
028ee4be 2090 struct mm_struct *mm = current->mm;
11bbd8b4
MK		 2091 struct prctl_mm_map prctl_map = {
2092 .auxv = NULL,
2093 .auxv_size = 0,
2094 .exe_fd = -1,
2095 };
fe8c7f5c
CG		 2096 struct vm_area_struct *vma;
2097 int error;
028ee4be 2098
f606b77f
CG		 2099 if (arg5 || (arg4 && (opt != PR_SET_MM_AUXV &&
2100 opt != PR_SET_MM_MAP &&
2101 opt != PR_SET_MM_MAP_SIZE)))
028ee4be
CG		 2102 return -EINVAL;
2103
f606b77f
CG		 2104#ifdef CONFIG_CHECKPOINT_RESTORE
2105 if (opt == PR_SET_MM_MAP || opt == PR_SET_MM_MAP_SIZE)
2106 return prctl_set_mm_map(opt, (const void __user *)addr, arg4);
2107#endif
2108
79f0713d 2109 if (!capable(CAP_SYS_RESOURCE))
028ee4be
CG		 2110 return -EPERM;
2111
6e399cd1
DB		 2112 if (opt == PR_SET_MM_EXE_FILE)
2113 return prctl_set_mm_exe_file(mm, (unsigned int)addr);
b32dfe37 2114
4a00e9df
AD		 2115 if (opt == PR_SET_MM_AUXV)
2116 return prctl_set_auxv(mm, addr, arg4);
2117
1ad75b9e 2118 if (addr >= TASK_SIZE || addr < mmap_min_addr)
028ee4be
CG		 2119 return -EINVAL;
2120
fe8c7f5c
CG		 2121 error = -EINVAL;
2122
bc81426f
MK		 2123 /*
2124 * arg_lock protects concurent updates of arg boundaries, we need
2125 * mmap_sem for a) concurrent sys_brk, b) finding VMA for addr
2126 * validation.
2127 */
2128 down_read(&mm->mmap_sem);
028ee4be
CG		 2129 vma = find_vma(mm, addr);
2130
bc81426f 2131 spin_lock(&mm->arg_lock);
4a00e9df
AD		 2132 prctl_map.start_code = mm->start_code;
2133 prctl_map.end_code = mm->end_code;
2134 prctl_map.start_data = mm->start_data;
2135 prctl_map.end_data = mm->end_data;
2136 prctl_map.start_brk = mm->start_brk;
2137 prctl_map.brk = mm->brk;
2138 prctl_map.start_stack = mm->start_stack;
2139 prctl_map.arg_start = mm->arg_start;
2140 prctl_map.arg_end = mm->arg_end;
2141 prctl_map.env_start = mm->env_start;
2142 prctl_map.env_end = mm->env_end;
4a00e9df 2143
028ee4be
CG		 2144 switch (opt) {
2145 case PR_SET_MM_START_CODE:
4a00e9df 2146 prctl_map.start_code = addr;
fe8c7f5c 2147 break;
028ee4be 2148 case PR_SET_MM_END_CODE:
4a00e9df 2149 prctl_map.end_code = addr;
028ee4be 2150 break;
028ee4be 2151 case PR_SET_MM_START_DATA:
4a00e9df 2152 prctl_map.start_data = addr;
028ee4be 2153 break;
fe8c7f5c 2154 case PR_SET_MM_END_DATA:
4a00e9df
AD		 2155 prctl_map.end_data = addr;
2156 break;
2157 case PR_SET_MM_START_STACK:
2158 prctl_map.start_stack = addr;
028ee4be 2159 break;
028ee4be 2160 case PR_SET_MM_START_BRK:
4a00e9df 2161 prctl_map.start_brk = addr;
028ee4be 2162 break;
028ee4be 2163 case PR_SET_MM_BRK:
4a00e9df 2164 prctl_map.brk = addr;
028ee4be 2165 break;
4a00e9df
AD		 2166 case PR_SET_MM_ARG_START:
2167 prctl_map.arg_start = addr;
2168 break;
2169 case PR_SET_MM_ARG_END:
2170 prctl_map.arg_end = addr;
2171 break;
2172 case PR_SET_MM_ENV_START:
2173 prctl_map.env_start = addr;
2174 break;
2175 case PR_SET_MM_ENV_END:
2176 prctl_map.env_end = addr;
2177 break;
2178 default:
2179 goto out;
2180 }
2181
11bbd8b4 2182 error = validate_prctl_map_addr(&prctl_map);
4a00e9df
AD		 2183 if (error)
2184 goto out;
028ee4be 2185
4a00e9df 2186 switch (opt) {
fe8c7f5c
CG		 2187 /*
2188 * If command line arguments and environment
2189 * are placed somewhere else on stack, we can
2190 * set them up here, ARG_START/END to setup
2191 * command line argumets and ENV_START/END
2192 * for environment.
2193 */
2194 case PR_SET_MM_START_STACK:
2195 case PR_SET_MM_ARG_START:
2196 case PR_SET_MM_ARG_END:
2197 case PR_SET_MM_ENV_START:
2198 case PR_SET_MM_ENV_END:
2199 if (!vma) {
2200 error = -EFAULT;
2201 goto out;
2202 }
028ee4be
CG		 2203 }
2204
4a00e9df
AD		 2205 mm->start_code = prctl_map.start_code;
2206 mm->end_code = prctl_map.end_code;
2207 mm->start_data = prctl_map.start_data;
2208 mm->end_data = prctl_map.end_data;
2209 mm->start_brk = prctl_map.start_brk;
2210 mm->brk = prctl_map.brk;
2211 mm->start_stack = prctl_map.start_stack;
2212 mm->arg_start = prctl_map.arg_start;
2213 mm->arg_end = prctl_map.arg_end;
2214 mm->env_start = prctl_map.env_start;
2215 mm->env_end = prctl_map.env_end;
2216
028ee4be 2217 error = 0;
028ee4be 2218out:
bc81426f
MK		 2219 spin_unlock(&mm->arg_lock);
2220 up_read(&mm->mmap_sem);
028ee4be
CG		 2221 return error;
2222}
300f786b 2223
52b36941 2224#ifdef CONFIG_CHECKPOINT_RESTORE
300f786b
CG		 2225static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
2226{
2227 return put_user(me->clear_child_tid, tid_addr);
2228}
52b36941 2229#else
300f786b
CG		 2230static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
2231{
2232 return -EINVAL;
2233}
028ee4be
CG		 2234#endif
2235
749860ce
PT		 2236static int propagate_has_child_subreaper(struct task_struct *p, void *data)
2237{
2238 /*
2239 * If task has has_child_subreaper - all its decendants
2240 * already have these flag too and new decendants will
2241 * inherit it on fork, skip them.
2242 *
2243 * If we've found child_reaper - skip descendants in
2244 * it's subtree as they will never get out pidns.
2245 */
2246 if (p->signal->has_child_subreaper ||
2247 is_child_reaper(task_pid(p)))
2248 return 0;
2249
2250 p->signal->has_child_subreaper = 1;
2251 return 1;
2252}
2253
7bbf1373 2254int __weak arch_prctl_spec_ctrl_get(struct task_struct *t, unsigned long which)
b617cfc8
TG		 2255{
2256 return -EINVAL;
2257}
2258
7bbf1373
KC		 2259int __weak arch_prctl_spec_ctrl_set(struct task_struct *t, unsigned long which,
2260 unsigned long ctrl)
b617cfc8
TG		 2261{
2262 return -EINVAL;
2263}
2264
a37b0715 2265#define PR_IO_FLUSHER (PF_MEMALLOC_NOIO | PF_LOCAL_THROTTLE)
8d19f1c8 2266
c4ea37c2
HC		 2267SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
2268 unsigned long, arg4, unsigned long, arg5)
1da177e4 2269{
b6dff3ec
DH		 2270 struct task_struct *me = current;
2271 unsigned char comm[sizeof(me->comm)];
2272 long error;
1da177e4 2273
d84f4f99
DH		 2274 error = security_task_prctl(option, arg2, arg3, arg4, arg5);
2275 if (error != -ENOSYS)
1da177e4
LT		 2276 return error;
2277
d84f4f99 2278 error = 0;
1da177e4 2279 switch (option) {
f3cbd435
AM		 2280 case PR_SET_PDEATHSIG:
2281 if (!valid_signal(arg2)) {
2282 error = -EINVAL;
1da177e4 2283 break;
f3cbd435
AM		 2284 }
2285 me->pdeath_signal = arg2;
2286 break;
2287 case PR_GET_PDEATHSIG:
2288 error = put_user(me->pdeath_signal, (int __user *)arg2);
2289 break;
2290 case PR_GET_DUMPABLE:
2291 error = get_dumpable(me->mm);
2292 break;
2293 case PR_SET_DUMPABLE:
2294 if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) {
2295 error = -EINVAL;
1da177e4 2296 break;
f3cbd435
AM		 2297 }
2298 set_dumpable(me->mm, arg2);
2299 break;
1da177e4 2300
f3cbd435
AM		 2301 case PR_SET_UNALIGN:
2302 error = SET_UNALIGN_CTL(me, arg2);
2303 break;
2304 case PR_GET_UNALIGN:
2305 error = GET_UNALIGN_CTL(me, arg2);
2306 break;
2307 case PR_SET_FPEMU:
2308 error = SET_FPEMU_CTL(me, arg2);
2309 break;
2310 case PR_GET_FPEMU:
2311 error = GET_FPEMU_CTL(me, arg2);
2312 break;
2313 case PR_SET_FPEXC:
2314 error = SET_FPEXC_CTL(me, arg2);
2315 break;
2316 case PR_GET_FPEXC:
2317 error = GET_FPEXC_CTL(me, arg2);
2318 break;
2319 case PR_GET_TIMING:
2320 error = PR_TIMING_STATISTICAL;
2321 break;
2322 case PR_SET_TIMING:
2323 if (arg2 != PR_TIMING_STATISTICAL)
2324 error = -EINVAL;
2325 break;
2326 case PR_SET_NAME:
2327 comm[sizeof(me->comm) - 1] = 0;
2328 if (strncpy_from_user(comm, (char __user *)arg2,
2329 sizeof(me->comm) - 1) < 0)
2330 return -EFAULT;
2331 set_task_comm(me, comm);
2332 proc_comm_connector(me);
2333 break;
2334 case PR_GET_NAME:
2335 get_task_comm(comm, me);
2336 if (copy_to_user((char __user *)arg2, comm, sizeof(comm)))
2337 return -EFAULT;
2338 break;
2339 case PR_GET_ENDIAN:
2340 error = GET_ENDIAN(me, arg2);
2341 break;
2342 case PR_SET_ENDIAN:
2343 error = SET_ENDIAN(me, arg2);
2344 break;
2345 case PR_GET_SECCOMP:
2346 error = prctl_get_seccomp();
2347 break;
2348 case PR_SET_SECCOMP:
2349 error = prctl_set_seccomp(arg2, (char __user *)arg3);
2350 break;
2351 case PR_GET_TSC:
2352 error = GET_TSC_CTL(arg2);
2353 break;
2354 case PR_SET_TSC:
2355 error = SET_TSC_CTL(arg2);
2356 break;
2357 case PR_TASK_PERF_EVENTS_DISABLE:
2358 error = perf_event_task_disable();
2359 break;
2360 case PR_TASK_PERF_EVENTS_ENABLE:
2361 error = perf_event_task_enable();
2362 break;
2363 case PR_GET_TIMERSLACK:
da8b44d5
JS		 2364 if (current->timer_slack_ns > ULONG_MAX)
2365 error = ULONG_MAX;
2366 else
2367 error = current->timer_slack_ns;
f3cbd435
AM		 2368 break;
2369 case PR_SET_TIMERSLACK:
2370 if (arg2 <= 0)
2371 current->timer_slack_ns =
6976675d 2372 current->default_timer_slack_ns;
f3cbd435
AM		 2373 else
2374 current->timer_slack_ns = arg2;
2375 break;
2376 case PR_MCE_KILL:
2377 if (arg4 | arg5)
2378 return -EINVAL;
2379 switch (arg2) {
2380 case PR_MCE_KILL_CLEAR:
2381 if (arg3 != 0)
4db96cf0 2382 return -EINVAL;
f3cbd435 2383 current->flags &= ~PF_MCE_PROCESS;
4db96cf0 2384 break;
f3cbd435
AM		 2385 case PR_MCE_KILL_SET:
2386 current->flags |= PF_MCE_PROCESS;
2387 if (arg3 == PR_MCE_KILL_EARLY)
2388 current->flags |= PF_MCE_EARLY;
2389 else if (arg3 == PR_MCE_KILL_LATE)
2390 current->flags &= ~PF_MCE_EARLY;
2391 else if (arg3 == PR_MCE_KILL_DEFAULT)
2392 current->flags &=
2393 ~(PF_MCE_EARLY|PF_MCE_PROCESS);
1087e9b4 2394 else
259e5e6c 2395 return -EINVAL;
259e5e6c 2396 break;
1da177e4 2397 default:
f3cbd435
AM		 2398 return -EINVAL;
2399 }
2400 break;
2401 case PR_MCE_KILL_GET:
2402 if (arg2 | arg3 | arg4 | arg5)
2403 return -EINVAL;
2404 if (current->flags & PF_MCE_PROCESS)
2405 error = (current->flags & PF_MCE_EARLY) ?
2406 PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE;
2407 else
2408 error = PR_MCE_KILL_DEFAULT;
2409 break;
2410 case PR_SET_MM:
2411 error = prctl_set_mm(arg2, arg3, arg4, arg5);
2412 break;
2413 case PR_GET_TID_ADDRESS:
2414 error = prctl_get_tid_address(me, (int __user **)arg2);
2415 break;
2416 case PR_SET_CHILD_SUBREAPER:
2417 me->signal->is_child_subreaper = !!arg2;
749860ce
PT		 2418 if (!arg2)
2419 break;
2420
2421 walk_process_tree(me, propagate_has_child_subreaper, NULL);
f3cbd435
AM		 2422 break;
2423 case PR_GET_CHILD_SUBREAPER:
2424 error = put_user(me->signal->is_child_subreaper,
2425 (int __user *)arg2);
2426 break;
2427 case PR_SET_NO_NEW_PRIVS:
2428 if (arg2 != 1 || arg3 || arg4 || arg5)
2429 return -EINVAL;
2430
1d4457f9 2431 task_set_no_new_privs(current);
f3cbd435
AM		 2432 break;
2433 case PR_GET_NO_NEW_PRIVS:
2434 if (arg2 || arg3 || arg4 || arg5)
2435 return -EINVAL;
1d4457f9 2436 return task_no_new_privs(current) ? 1 : 0;
a0715cc2
AT		 2437 case PR_GET_THP_DISABLE:
2438 if (arg2 || arg3 || arg4 || arg5)
2439 return -EINVAL;
18600332 2440 error = !!test_bit(MMF_DISABLE_THP, &me->mm->flags);
a0715cc2
AT		 2441 break;
2442 case PR_SET_THP_DISABLE:
2443 if (arg3 || arg4 || arg5)
2444 return -EINVAL;
17b0573d
MH		 2445 if (down_write_killable(&me->mm->mmap_sem))
2446 return -EINTR;
a0715cc2 2447 if (arg2)
18600332 2448 set_bit(MMF_DISABLE_THP, &me->mm->flags);
a0715cc2 2449 else
18600332 2450 clear_bit(MMF_DISABLE_THP, &me->mm->flags);
a0715cc2
AT		 2451 up_write(&me->mm->mmap_sem);
2452 break;
fe3d197f 2453 case PR_MPX_ENABLE_MANAGEMENT:
fe3d197f 2454 case PR_MPX_DISABLE_MANAGEMENT:
f240652b
DH		 2455 /* No longer implemented: */
2456 return -EINVAL;
9791554b
PB		 2457 case PR_SET_FP_MODE:
2458 error = SET_FP_MODE(me, arg2);
2459 break;
2460 case PR_GET_FP_MODE:
2461 error = GET_FP_MODE(me);
2462 break;
2d2123bc
DM		 2463 case PR_SVE_SET_VL:
2464 error = SVE_SET_VL(arg2);
2465 break;
2466 case PR_SVE_GET_VL:
2467 error = SVE_GET_VL();
2468 break;
b617cfc8
TG		 2469 case PR_GET_SPECULATION_CTRL:
2470 if (arg3 || arg4 || arg5)
2471 return -EINVAL;
7bbf1373 2472 error = arch_prctl_spec_ctrl_get(me, arg2);
b617cfc8
TG		 2473 break;
2474 case PR_SET_SPECULATION_CTRL:
2475 if (arg4 || arg5)
2476 return -EINVAL;
7bbf1373 2477 error = arch_prctl_spec_ctrl_set(me, arg2, arg3);
b617cfc8 2478 break;
ba830885
KM		 2479 case PR_PAC_RESET_KEYS:
2480 if (arg3 || arg4 || arg5)
2481 return -EINVAL;
2482 error = PAC_RESET_KEYS(me, arg2);
2483 break;
63f0c603 2484 case PR_SET_TAGGED_ADDR_CTRL:
3e91ec89
CM		 2485 if (arg3 || arg4 || arg5)
2486 return -EINVAL;
63f0c603
CM		 2487 error = SET_TAGGED_ADDR_CTRL(arg2);
2488 break;
2489 case PR_GET_TAGGED_ADDR_CTRL:
3e91ec89
CM		 2490 if (arg2 || arg3 || arg4 || arg5)
2491 return -EINVAL;
63f0c603
CM		 2492 error = GET_TAGGED_ADDR_CTRL();
2493 break;
8d19f1c8
MC		 2494 case PR_SET_IO_FLUSHER:
2495 if (!capable(CAP_SYS_RESOURCE))
2496 return -EPERM;
2497
2498 if (arg3 || arg4 || arg5)
2499 return -EINVAL;
2500
2501 if (arg2 == 1)
2502 current->flags |= PR_IO_FLUSHER;
2503 else if (!arg2)
2504 current->flags &= ~PR_IO_FLUSHER;
2505 else
2506 return -EINVAL;
2507 break;
2508 case PR_GET_IO_FLUSHER:
2509 if (!capable(CAP_SYS_RESOURCE))
2510 return -EPERM;
2511
2512 if (arg2 || arg3 || arg4 || arg5)
2513 return -EINVAL;
2514
2515 error = (current->flags & PR_IO_FLUSHER) == PR_IO_FLUSHER;
2516 break;
f3cbd435
AM		 2517 default:
2518 error = -EINVAL;
2519 break;
1da177e4
LT		 2520 }
2521 return error;
2522}
3cfc348b 2523
836f92ad
HC		 2524SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
2525 struct getcpu_cache __user *, unused)
3cfc348b
AK		 2526{
2527 int err = 0;
2528 int cpu = raw_smp_processor_id();
ec94fc3d 2529
3cfc348b
AK		 2530 if (cpup)
2531 err |= put_user(cpu, cpup);
2532 if (nodep)
2533 err |= put_user(cpu_to_node(cpu), nodep);
3cfc348b
AK		 2534 return err ? -EFAULT : 0;
2535}
10a0a8d4 2536
4a22f166
SR		 2537/**
2538 * do_sysinfo - fill in sysinfo struct
2539 * @info: pointer to buffer to fill
2540 */
2541static int do_sysinfo(struct sysinfo *info)
2542{
2543 unsigned long mem_total, sav_total;
2544 unsigned int mem_unit, bitcount;
dc1b7b6c 2545 struct timespec64 tp;
4a22f166
SR		 2546
2547 memset(info, 0, sizeof(struct sysinfo));
2548
dc1b7b6c 2549 ktime_get_boottime_ts64(&tp);
ecc421e0 2550 timens_add_boottime(&tp);
4a22f166
SR		 2551 info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0);
2552
2553 get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT);
2554
2555 info->procs = nr_threads;
2556
2557 si_meminfo(info);
2558 si_swapinfo(info);
2559
2560 /*
2561 * If the sum of all the available memory (i.e. ram + swap)
2562 * is less than can be stored in a 32 bit unsigned long then
2563 * we can be binary compatible with 2.2.x kernels. If not,
2564 * well, in that case 2.2.x was broken anyways...
2565 *
2566 * -Erik Andersen <andersee@debian.org>
2567 */
2568
2569 mem_total = info->totalram + info->totalswap;
2570 if (mem_total < info->totalram || mem_total < info->totalswap)
2571 goto out;
2572 bitcount = 0;
2573 mem_unit = info->mem_unit;
2574 while (mem_unit > 1) {
2575 bitcount++;
2576 mem_unit >>= 1;
2577 sav_total = mem_total;
2578 mem_total <<= 1;
2579 if (mem_total < sav_total)
2580 goto out;
2581 }
2582
2583 /*
2584 * If mem_total did not overflow, multiply all memory values by
2585 * info->mem_unit and set it to 1. This leaves things compatible
2586 * with 2.2.x, and also retains compatibility with earlier 2.4.x
2587 * kernels...
2588 */
2589
2590 info->mem_unit = 1;
2591 info->totalram <<= bitcount;
2592 info->freeram <<= bitcount;
2593 info->sharedram <<= bitcount;
2594 info->bufferram <<= bitcount;
2595 info->totalswap <<= bitcount;
2596 info->freeswap <<= bitcount;
2597 info->totalhigh <<= bitcount;
2598 info->freehigh <<= bitcount;
2599
2600out:
2601 return 0;
2602}
2603
2604SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info)
2605{
2606 struct sysinfo val;
2607
2608 do_sysinfo(&val);
2609
2610 if (copy_to_user(info, &val, sizeof(struct sysinfo)))
2611 return -EFAULT;
2612
2613 return 0;
2614}
2615
2616#ifdef CONFIG_COMPAT
2617struct compat_sysinfo {
2618 s32 uptime;
2619 u32 loads[3];
2620 u32 totalram;
2621 u32 freeram;
2622 u32 sharedram;
2623 u32 bufferram;
2624 u32 totalswap;
2625 u32 freeswap;
2626 u16 procs;
2627 u16 pad;
2628 u32 totalhigh;
2629 u32 freehigh;
2630 u32 mem_unit;
2631 char _f[20-2*sizeof(u32)-sizeof(int)];
2632};
2633
2634COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
2635{
2636 struct sysinfo s;
2637
2638 do_sysinfo(&s);
2639
2640 /* Check to see if any memory value is too large for 32-bit and scale
2641 * down if needed
2642 */
0baae41e 2643 if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) {
4a22f166
SR		 2644 int bitcount = 0;
2645
2646 while (s.mem_unit < PAGE_SIZE) {
2647 s.mem_unit <<= 1;
2648 bitcount++;
2649 }
2650
2651 s.totalram >>= bitcount;
2652 s.freeram >>= bitcount;
2653 s.sharedram >>= bitcount;
2654 s.bufferram >>= bitcount;
2655 s.totalswap >>= bitcount;
2656 s.freeswap >>= bitcount;
2657 s.totalhigh >>= bitcount;
2658 s.freehigh >>= bitcount;
2659 }
2660
96d4f267 2661 if (!access_ok(info, sizeof(struct compat_sysinfo)) ||
4a22f166
SR		 2662 __put_user(s.uptime, &info->uptime) ||
2663 __put_user(s.loads[0], &info->loads[0]) ||
2664 __put_user(s.loads[1], &info->loads[1]) ||
2665 __put_user(s.loads[2], &info->loads[2]) ||
2666 __put_user(s.totalram, &info->totalram) ||
2667 __put_user(s.freeram, &info->freeram) ||
2668 __put_user(s.sharedram, &info->sharedram) ||
2669 __put_user(s.bufferram, &info->bufferram) ||
2670 __put_user(s.totalswap, &info->totalswap) ||
2671 __put_user(s.freeswap, &info->freeswap) ||
2672 __put_user(s.procs, &info->procs) ||
2673 __put_user(s.totalhigh, &info->totalhigh) ||
2674 __put_user(s.freehigh, &info->freehigh) ||
2675 __put_user(s.mem_unit, &info->mem_unit))
2676 return -EFAULT;
2677
2678 return 0;
2679}
2680#endif /* CONFIG_COMPAT */
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