Merge tag 'sched_ext-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj...
[linux-2.6-block.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 9#include <linux/mm.h>
5c26f6ac 10#include <linux/mm_inline.h>
1da177e4
LT
11#include <linux/utsname.h>
12#include <linux/mman.h>
1da177e4
LT
13#include <linux/reboot.h>
14#include <linux/prctl.h>
1da177e4
LT
15#include <linux/highuid.h>
16#include <linux/fs.h>
74da1ff7 17#include <linux/kmod.h>
d7597f59 18#include <linux/ksm.h>
cdd6c482 19#include <linux/perf_event.h>
3e88c553 20#include <linux/resource.h>
dc009d92 21#include <linux/kernel.h>
1da177e4 22#include <linux/workqueue.h>
c59ede7b 23#include <linux/capability.h>
1da177e4
LT
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>
37608ba3 29#include <linux/random.h>
1da177e4
LT
30#include <linux/suspend.h>
31#include <linux/tty.h>
7ed20e1a 32#include <linux/signal.h>
9f46080c 33#include <linux/cn_proc.h>
3cfc348b 34#include <linux/getcpu.h>
6eaeeaba 35#include <linux/task_io_accounting_ops.h>
1d9d02fe 36#include <linux/seccomp.h>
4047727e 37#include <linux/cpu.h>
e28cbf22 38#include <linux/personality.h>
e3d5a27d 39#include <linux/ptrace.h>
5ad4e53b 40#include <linux/fs_struct.h>
b32dfe37
CG
41#include <linux/file.h>
42#include <linux/mount.h>
5a0e3ad6 43#include <linux/gfp.h>
40dc166c 44#include <linux/syscore_ops.h>
be27425d
AK
45#include <linux/version.h>
46#include <linux/ctype.h>
1446e1df 47#include <linux/syscall_user_dispatch.h>
1da177e4
LT
48
49#include <linux/compat.h>
50#include <linux/syscalls.h>
00d7c05a 51#include <linux/kprobes.h>
acce292c 52#include <linux/user_namespace.h>
ecc421e0 53#include <linux/time_namespace.h>
7fe5e042 54#include <linux/binfmts.h>
1da177e4 55
4a22f166 56#include <linux/sched.h>
4eb5aaa3 57#include <linux/sched/autogroup.h>
4f17722c 58#include <linux/sched/loadavg.h>
03441a34 59#include <linux/sched/stat.h>
6e84f315 60#include <linux/sched/mm.h>
f7ccbae4 61#include <linux/sched/coredump.h>
29930025 62#include <linux/sched/task.h>
32ef5517 63#include <linux/sched/cputime.h>
4a22f166
SR
64#include <linux/rcupdate.h>
65#include <linux/uidgid.h>
66#include <linux/cred.h>
67
b617cfc8
TG
68#include <linux/nospec.h>
69
04c6862c 70#include <linux/kmsg_dump.h>
be27425d
AK
71/* Move somewhere else to avoid recompiling? */
72#include <generated/utsrelease.h>
04c6862c 73
7c0f6ba6 74#include <linux/uaccess.h>
1da177e4
LT
75#include <asm/io.h>
76#include <asm/unistd.h>
77
e530dca5
DB
78#include "uid16.h"
79
1da177e4 80#ifndef SET_UNALIGN_CTL
ec94fc3d 81# define SET_UNALIGN_CTL(a, b) (-EINVAL)
1da177e4
LT
82#endif
83#ifndef GET_UNALIGN_CTL
ec94fc3d 84# define GET_UNALIGN_CTL(a, b) (-EINVAL)
1da177e4
LT
85#endif
86#ifndef SET_FPEMU_CTL
ec94fc3d 87# define SET_FPEMU_CTL(a, b) (-EINVAL)
1da177e4
LT
88#endif
89#ifndef GET_FPEMU_CTL
ec94fc3d 90# define GET_FPEMU_CTL(a, b) (-EINVAL)
1da177e4
LT
91#endif
92#ifndef SET_FPEXC_CTL
ec94fc3d 93# define SET_FPEXC_CTL(a, b) (-EINVAL)
1da177e4
LT
94#endif
95#ifndef GET_FPEXC_CTL
ec94fc3d 96# define GET_FPEXC_CTL(a, b) (-EINVAL)
1da177e4 97#endif
651d765d 98#ifndef GET_ENDIAN
ec94fc3d 99# define GET_ENDIAN(a, b) (-EINVAL)
651d765d
AB
100#endif
101#ifndef SET_ENDIAN
ec94fc3d 102# define SET_ENDIAN(a, b) (-EINVAL)
651d765d 103#endif
8fb402bc
EB
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
9791554b
PB
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
2d2123bc
DM
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
9e4ab6c8
MB
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
ba830885
KM
128#ifndef PAC_RESET_KEYS
129# define PAC_RESET_KEYS(a, b) (-EINVAL)
130#endif
20169862
PC
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
63f0c603
CM
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
1fd96a3e
AC
143#ifndef RISCV_V_SET_CONTROL
144# define RISCV_V_SET_CONTROL(a) (-EINVAL)
145#endif
146#ifndef RISCV_V_GET_CONTROL
147# define RISCV_V_GET_CONTROL() (-EINVAL)
148#endif
6b9391b5
CJ
149#ifndef RISCV_SET_ICACHE_FLUSH_CTX
150# define RISCV_SET_ICACHE_FLUSH_CTX(a, b) (-EINVAL)
151#endif
628d701f
BG
152#ifndef PPC_GET_DEXCR_ASPECT
153# define PPC_GET_DEXCR_ASPECT(a, b) (-EINVAL)
154#endif
155#ifndef PPC_SET_DEXCR_ASPECT
156# define PPC_SET_DEXCR_ASPECT(a, b, c) (-EINVAL)
157#endif
1da177e4
LT
158
159/*
160 * this is where the system-wide overflow UID and GID are defined, for
161 * architectures that now have 32-bit UID/GID but didn't in the past
162 */
163
164int overflowuid = DEFAULT_OVERFLOWUID;
165int overflowgid = DEFAULT_OVERFLOWGID;
166
1da177e4
LT
167EXPORT_SYMBOL(overflowuid);
168EXPORT_SYMBOL(overflowgid);
1da177e4
LT
169
170/*
171 * the same as above, but for filesystems which can only store a 16-bit
172 * UID and GID. as such, this is needed on all architectures
173 */
174
175int fs_overflowuid = DEFAULT_FS_OVERFLOWUID;
8b2770a4 176int fs_overflowgid = DEFAULT_FS_OVERFLOWGID;
1da177e4
LT
177
178EXPORT_SYMBOL(fs_overflowuid);
179EXPORT_SYMBOL(fs_overflowgid);
180
fc832ad3
SH
181/*
182 * Returns true if current's euid is same as p's uid or euid,
183 * or has CAP_SYS_NICE to p's user_ns.
184 *
185 * Called with rcu_read_lock, creds are safe
186 */
187static bool set_one_prio_perm(struct task_struct *p)
188{
189 const struct cred *cred = current_cred(), *pcred = __task_cred(p);
190
5af66203
EB
191 if (uid_eq(pcred->uid, cred->euid) ||
192 uid_eq(pcred->euid, cred->euid))
fc832ad3 193 return true;
c4a4d603 194 if (ns_capable(pcred->user_ns, CAP_SYS_NICE))
fc832ad3
SH
195 return true;
196 return false;
197}
198
c69e8d9c
DH
199/*
200 * set the priority of a task
201 * - the caller must hold the RCU read lock
202 */
1da177e4
LT
203static int set_one_prio(struct task_struct *p, int niceval, int error)
204{
205 int no_nice;
206
fc832ad3 207 if (!set_one_prio_perm(p)) {
1da177e4
LT
208 error = -EPERM;
209 goto out;
210 }
e43379f1 211 if (niceval < task_nice(p) && !can_nice(p, niceval)) {
1da177e4
LT
212 error = -EACCES;
213 goto out;
214 }
215 no_nice = security_task_setnice(p, niceval);
216 if (no_nice) {
217 error = no_nice;
218 goto out;
219 }
220 if (error == -ESRCH)
221 error = 0;
222 set_user_nice(p, niceval);
223out:
224 return error;
225}
226
754fe8d2 227SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
1da177e4
LT
228{
229 struct task_struct *g, *p;
230 struct user_struct *user;
86a264ab 231 const struct cred *cred = current_cred();
1da177e4 232 int error = -EINVAL;
41487c65 233 struct pid *pgrp;
7b44ab97 234 kuid_t uid;
1da177e4 235
3e88c553 236 if (which > PRIO_USER || which < PRIO_PROCESS)
1da177e4
LT
237 goto out;
238
239 /* normalize: avoid signed division (rounding problems) */
240 error = -ESRCH;
c4a4d2f4
DY
241 if (niceval < MIN_NICE)
242 niceval = MIN_NICE;
243 if (niceval > MAX_NICE)
244 niceval = MAX_NICE;
1da177e4 245
d4581a23 246 rcu_read_lock();
1da177e4 247 switch (which) {
ec94fc3d 248 case PRIO_PROCESS:
249 if (who)
250 p = find_task_by_vpid(who);
251 else
252 p = current;
253 if (p)
254 error = set_one_prio(p, niceval, error);
255 break;
256 case PRIO_PGRP:
257 if (who)
258 pgrp = find_vpid(who);
259 else
260 pgrp = task_pgrp(current);
7f8ca0ed 261 read_lock(&tasklist_lock);
ec94fc3d 262 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
263 error = set_one_prio(p, niceval, error);
264 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
7f8ca0ed 265 read_unlock(&tasklist_lock);
ec94fc3d 266 break;
267 case PRIO_USER:
268 uid = make_kuid(cred->user_ns, who);
269 user = cred->user;
270 if (!who)
271 uid = cred->uid;
272 else if (!uid_eq(uid, cred->uid)) {
273 user = find_user(uid);
274 if (!user)
86a264ab 275 goto out_unlock; /* No processes for this user */
ec94fc3d 276 }
7f8ca0ed 277 for_each_process_thread(g, p) {
8639b461 278 if (uid_eq(task_uid(p), uid) && task_pid_vnr(p))
ec94fc3d 279 error = set_one_prio(p, niceval, error);
7f8ca0ed 280 }
ec94fc3d 281 if (!uid_eq(uid, cred->uid))
282 free_uid(user); /* For find_user() */
283 break;
1da177e4
LT
284 }
285out_unlock:
d4581a23 286 rcu_read_unlock();
1da177e4
LT
287out:
288 return error;
289}
290
291/*
292 * Ugh. To avoid negative return values, "getpriority()" will
293 * not return the normal nice-value, but a negated value that
294 * has been offset by 20 (ie it returns 40..1 instead of -20..19)
295 * to stay compatible.
296 */
754fe8d2 297SYSCALL_DEFINE2(getpriority, int, which, int, who)
1da177e4
LT
298{
299 struct task_struct *g, *p;
300 struct user_struct *user;
86a264ab 301 const struct cred *cred = current_cred();
1da177e4 302 long niceval, retval = -ESRCH;
41487c65 303 struct pid *pgrp;
7b44ab97 304 kuid_t uid;
1da177e4 305
3e88c553 306 if (which > PRIO_USER || which < PRIO_PROCESS)
1da177e4
LT
307 return -EINVAL;
308
70118837 309 rcu_read_lock();
1da177e4 310 switch (which) {
ec94fc3d 311 case PRIO_PROCESS:
312 if (who)
313 p = find_task_by_vpid(who);
314 else
315 p = current;
316 if (p) {
317 niceval = nice_to_rlimit(task_nice(p));
318 if (niceval > retval)
319 retval = niceval;
320 }
321 break;
322 case PRIO_PGRP:
323 if (who)
324 pgrp = find_vpid(who);
325 else
326 pgrp = task_pgrp(current);
7f8ca0ed 327 read_lock(&tasklist_lock);
ec94fc3d 328 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
329 niceval = nice_to_rlimit(task_nice(p));
330 if (niceval > retval)
331 retval = niceval;
332 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
7f8ca0ed 333 read_unlock(&tasklist_lock);
ec94fc3d 334 break;
335 case PRIO_USER:
336 uid = make_kuid(cred->user_ns, who);
337 user = cred->user;
338 if (!who)
339 uid = cred->uid;
340 else if (!uid_eq(uid, cred->uid)) {
341 user = find_user(uid);
342 if (!user)
343 goto out_unlock; /* No processes for this user */
344 }
7f8ca0ed 345 for_each_process_thread(g, p) {
8639b461 346 if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) {
7aa2c016 347 niceval = nice_to_rlimit(task_nice(p));
1da177e4
LT
348 if (niceval > retval)
349 retval = niceval;
350 }
7f8ca0ed 351 }
ec94fc3d 352 if (!uid_eq(uid, cred->uid))
353 free_uid(user); /* for find_user() */
354 break;
1da177e4
LT
355 }
356out_unlock:
70118837 357 rcu_read_unlock();
1da177e4
LT
358
359 return retval;
360}
361
1da177e4
LT
362/*
363 * Unprivileged users may change the real gid to the effective gid
364 * or vice versa. (BSD-style)
365 *
366 * If you set the real gid at all, or set the effective gid to a value not
367 * equal to the real gid, then the saved gid is set to the new effective gid.
368 *
369 * This makes it possible for a setgid program to completely drop its
370 * privileges, which is often a useful assertion to make when you are doing
371 * a security audit over a program.
372 *
373 * The general idea is that a program which uses just setregid() will be
374 * 100% compatible with BSD. A program which uses just setgid() will be
ec94fc3d 375 * 100% compatible with POSIX with saved IDs.
1da177e4
LT
376 *
377 * SMP: There are not races, the GIDs are checked only by filesystem
378 * operations (as far as semantic preservation is concerned).
379 */
2813893f 380#ifdef CONFIG_MULTIUSER
e530dca5 381long __sys_setregid(gid_t rgid, gid_t egid)
1da177e4 382{
a29c33f4 383 struct user_namespace *ns = current_user_ns();
d84f4f99
DH
384 const struct cred *old;
385 struct cred *new;
1da177e4 386 int retval;
a29c33f4
EB
387 kgid_t krgid, kegid;
388
389 krgid = make_kgid(ns, rgid);
390 kegid = make_kgid(ns, egid);
391
392 if ((rgid != (gid_t) -1) && !gid_valid(krgid))
393 return -EINVAL;
394 if ((egid != (gid_t) -1) && !gid_valid(kegid))
395 return -EINVAL;
1da177e4 396
d84f4f99
DH
397 new = prepare_creds();
398 if (!new)
399 return -ENOMEM;
400 old = current_cred();
401
d84f4f99 402 retval = -EPERM;
1da177e4 403 if (rgid != (gid_t) -1) {
a29c33f4
EB
404 if (gid_eq(old->gid, krgid) ||
405 gid_eq(old->egid, krgid) ||
111767c1 406 ns_capable_setid(old->user_ns, CAP_SETGID))
a29c33f4 407 new->gid = krgid;
1da177e4 408 else
d84f4f99 409 goto error;
1da177e4
LT
410 }
411 if (egid != (gid_t) -1) {
a29c33f4
EB
412 if (gid_eq(old->gid, kegid) ||
413 gid_eq(old->egid, kegid) ||
414 gid_eq(old->sgid, kegid) ||
111767c1 415 ns_capable_setid(old->user_ns, CAP_SETGID))
a29c33f4 416 new->egid = kegid;
756184b7 417 else
d84f4f99 418 goto error;
1da177e4 419 }
d84f4f99 420
1da177e4 421 if (rgid != (gid_t) -1 ||
a29c33f4 422 (egid != (gid_t) -1 && !gid_eq(kegid, old->gid)))
d84f4f99
DH
423 new->sgid = new->egid;
424 new->fsgid = new->egid;
425
39030e13
TC
426 retval = security_task_fix_setgid(new, old, LSM_SETID_RE);
427 if (retval < 0)
428 goto error;
429
d84f4f99
DH
430 return commit_creds(new);
431
432error:
433 abort_creds(new);
434 return retval;
1da177e4
LT
435}
436
e530dca5
DB
437SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
438{
439 return __sys_setregid(rgid, egid);
440}
441
1da177e4 442/*
ec94fc3d 443 * setgid() is implemented like SysV w/ SAVED_IDS
1da177e4
LT
444 *
445 * SMP: Same implicit races as above.
446 */
e530dca5 447long __sys_setgid(gid_t gid)
1da177e4 448{
a29c33f4 449 struct user_namespace *ns = current_user_ns();
d84f4f99
DH
450 const struct cred *old;
451 struct cred *new;
1da177e4 452 int retval;
a29c33f4
EB
453 kgid_t kgid;
454
455 kgid = make_kgid(ns, gid);
456 if (!gid_valid(kgid))
457 return -EINVAL;
1da177e4 458
d84f4f99
DH
459 new = prepare_creds();
460 if (!new)
461 return -ENOMEM;
462 old = current_cred();
463
d84f4f99 464 retval = -EPERM;
111767c1 465 if (ns_capable_setid(old->user_ns, CAP_SETGID))
a29c33f4
EB
466 new->gid = new->egid = new->sgid = new->fsgid = kgid;
467 else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid))
468 new->egid = new->fsgid = kgid;
1da177e4 469 else
d84f4f99 470 goto error;
1da177e4 471
39030e13
TC
472 retval = security_task_fix_setgid(new, old, LSM_SETID_ID);
473 if (retval < 0)
474 goto error;
475
d84f4f99
DH
476 return commit_creds(new);
477
478error:
479 abort_creds(new);
480 return retval;
1da177e4 481}
54e99124 482
e530dca5
DB
483SYSCALL_DEFINE1(setgid, gid_t, gid)
484{
485 return __sys_setgid(gid);
486}
487
d84f4f99
DH
488/*
489 * change the user struct in a credentials set to match the new UID
490 */
491static int set_user(struct cred *new)
1da177e4
LT
492{
493 struct user_struct *new_user;
494
078de5f7 495 new_user = alloc_uid(new->uid);
1da177e4
LT
496 if (!new_user)
497 return -EAGAIN;
498
c923a8e7
EB
499 free_uid(new->user);
500 new->user = new_user;
501 return 0;
502}
503
504static void flag_nproc_exceeded(struct cred *new)
505{
506 if (new->ucounts == current_ucounts())
507 return;
508
72fa5997
VK
509 /*
510 * We don't fail in case of NPROC limit excess here because too many
511 * poorly written programs don't check set*uid() return code, assuming
512 * it never fails if called by root. We may still enforce NPROC limit
513 * for programs doing set*uid()+execve() by harmlessly deferring the
514 * failure to the execve() stage.
515 */
de399236 516 if (is_rlimit_overlimit(new->ucounts, UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC)) &&
c923a8e7 517 new->user != INIT_USER)
72fa5997
VK
518 current->flags |= PF_NPROC_EXCEEDED;
519 else
520 current->flags &= ~PF_NPROC_EXCEEDED;
1da177e4
LT
521}
522
523/*
524 * Unprivileged users may change the real uid to the effective uid
525 * or vice versa. (BSD-style)
526 *
527 * If you set the real uid at all, or set the effective uid to a value not
528 * equal to the real uid, then the saved uid is set to the new effective uid.
529 *
530 * This makes it possible for a setuid program to completely drop its
531 * privileges, which is often a useful assertion to make when you are doing
532 * a security audit over a program.
533 *
534 * The general idea is that a program which uses just setreuid() will be
535 * 100% compatible with BSD. A program which uses just setuid() will be
ec94fc3d 536 * 100% compatible with POSIX with saved IDs.
1da177e4 537 */
e530dca5 538long __sys_setreuid(uid_t ruid, uid_t euid)
1da177e4 539{
a29c33f4 540 struct user_namespace *ns = current_user_ns();
d84f4f99
DH
541 const struct cred *old;
542 struct cred *new;
1da177e4 543 int retval;
a29c33f4
EB
544 kuid_t kruid, keuid;
545
546 kruid = make_kuid(ns, ruid);
547 keuid = make_kuid(ns, euid);
548
549 if ((ruid != (uid_t) -1) && !uid_valid(kruid))
550 return -EINVAL;
551 if ((euid != (uid_t) -1) && !uid_valid(keuid))
552 return -EINVAL;
1da177e4 553
d84f4f99
DH
554 new = prepare_creds();
555 if (!new)
556 return -ENOMEM;
557 old = current_cred();
558
d84f4f99 559 retval = -EPERM;
1da177e4 560 if (ruid != (uid_t) -1) {
a29c33f4
EB
561 new->uid = kruid;
562 if (!uid_eq(old->uid, kruid) &&
563 !uid_eq(old->euid, kruid) &&
40852275 564 !ns_capable_setid(old->user_ns, CAP_SETUID))
d84f4f99 565 goto error;
1da177e4
LT
566 }
567
568 if (euid != (uid_t) -1) {
a29c33f4
EB
569 new->euid = keuid;
570 if (!uid_eq(old->uid, keuid) &&
571 !uid_eq(old->euid, keuid) &&
572 !uid_eq(old->suid, keuid) &&
40852275 573 !ns_capable_setid(old->user_ns, CAP_SETUID))
d84f4f99 574 goto error;
1da177e4
LT
575 }
576
a29c33f4 577 if (!uid_eq(new->uid, old->uid)) {
54e99124
DG
578 retval = set_user(new);
579 if (retval < 0)
580 goto error;
581 }
1da177e4 582 if (ruid != (uid_t) -1 ||
a29c33f4 583 (euid != (uid_t) -1 && !uid_eq(keuid, old->uid)))
d84f4f99
DH
584 new->suid = new->euid;
585 new->fsuid = new->euid;
1da177e4 586
d84f4f99
DH
587 retval = security_task_fix_setuid(new, old, LSM_SETID_RE);
588 if (retval < 0)
589 goto error;
1da177e4 590
905ae01c
AG
591 retval = set_cred_ucounts(new);
592 if (retval < 0)
593 goto error;
594
c923a8e7 595 flag_nproc_exceeded(new);
d84f4f99 596 return commit_creds(new);
1da177e4 597
d84f4f99
DH
598error:
599 abort_creds(new);
600 return retval;
601}
ec94fc3d 602
e530dca5
DB
603SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
604{
605 return __sys_setreuid(ruid, euid);
606}
607
1da177e4 608/*
ec94fc3d 609 * setuid() is implemented like SysV with SAVED_IDS
610 *
1da177e4 611 * Note that SAVED_ID's is deficient in that a setuid root program
ec94fc3d 612 * like sendmail, for example, cannot set its uid to be a normal
1da177e4
LT
613 * user and then switch back, because if you're root, setuid() sets
614 * the saved uid too. If you don't like this, blame the bright people
615 * in the POSIX committee and/or USG. Note that the BSD-style setreuid()
616 * will allow a root program to temporarily drop privileges and be able to
ec94fc3d 617 * regain them by swapping the real and effective uid.
1da177e4 618 */
e530dca5 619long __sys_setuid(uid_t uid)
1da177e4 620{
a29c33f4 621 struct user_namespace *ns = current_user_ns();
d84f4f99
DH
622 const struct cred *old;
623 struct cred *new;
1da177e4 624 int retval;
a29c33f4
EB
625 kuid_t kuid;
626
627 kuid = make_kuid(ns, uid);
628 if (!uid_valid(kuid))
629 return -EINVAL;
1da177e4 630
d84f4f99
DH
631 new = prepare_creds();
632 if (!new)
633 return -ENOMEM;
634 old = current_cred();
635
d84f4f99 636 retval = -EPERM;
40852275 637 if (ns_capable_setid(old->user_ns, CAP_SETUID)) {
a29c33f4
EB
638 new->suid = new->uid = kuid;
639 if (!uid_eq(kuid, old->uid)) {
54e99124
DG
640 retval = set_user(new);
641 if (retval < 0)
642 goto error;
d84f4f99 643 }
a29c33f4 644 } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) {
d84f4f99 645 goto error;
1da177e4 646 }
1da177e4 647
a29c33f4 648 new->fsuid = new->euid = kuid;
d84f4f99
DH
649
650 retval = security_task_fix_setuid(new, old, LSM_SETID_ID);
651 if (retval < 0)
652 goto error;
1da177e4 653
905ae01c
AG
654 retval = set_cred_ucounts(new);
655 if (retval < 0)
656 goto error;
657
c923a8e7 658 flag_nproc_exceeded(new);
d84f4f99 659 return commit_creds(new);
1da177e4 660
d84f4f99
DH
661error:
662 abort_creds(new);
663 return retval;
1da177e4
LT
664}
665
e530dca5
DB
666SYSCALL_DEFINE1(setuid, uid_t, uid)
667{
668 return __sys_setuid(uid);
669}
670
1da177e4
LT
671
672/*
673 * This function implements a generic ability to update ruid, euid,
674 * and suid. This allows you to implement the 4.4 compatible seteuid().
675 */
e530dca5 676long __sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
1da177e4 677{
a29c33f4 678 struct user_namespace *ns = current_user_ns();
d84f4f99
DH
679 const struct cred *old;
680 struct cred *new;
1da177e4 681 int retval;
a29c33f4 682 kuid_t kruid, keuid, ksuid;
659c0ce1 683 bool ruid_new, euid_new, suid_new;
a29c33f4
EB
684
685 kruid = make_kuid(ns, ruid);
686 keuid = make_kuid(ns, euid);
687 ksuid = make_kuid(ns, suid);
688
689 if ((ruid != (uid_t) -1) && !uid_valid(kruid))
690 return -EINVAL;
691
692 if ((euid != (uid_t) -1) && !uid_valid(keuid))
693 return -EINVAL;
694
695 if ((suid != (uid_t) -1) && !uid_valid(ksuid))
696 return -EINVAL;
1da177e4 697
659c0ce1
OM
698 old = current_cred();
699
700 /* check for no-op */
701 if ((ruid == (uid_t) -1 || uid_eq(kruid, old->uid)) &&
702 (euid == (uid_t) -1 || (uid_eq(keuid, old->euid) &&
703 uid_eq(keuid, old->fsuid))) &&
704 (suid == (uid_t) -1 || uid_eq(ksuid, old->suid)))
705 return 0;
706
707 ruid_new = ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) &&
708 !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid);
709 euid_new = euid != (uid_t) -1 && !uid_eq(keuid, old->uid) &&
710 !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid);
711 suid_new = suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) &&
712 !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid);
713 if ((ruid_new || euid_new || suid_new) &&
714 !ns_capable_setid(old->user_ns, CAP_SETUID))
715 return -EPERM;
716
d84f4f99
DH
717 new = prepare_creds();
718 if (!new)
719 return -ENOMEM;
720
1da177e4 721 if (ruid != (uid_t) -1) {
a29c33f4
EB
722 new->uid = kruid;
723 if (!uid_eq(kruid, old->uid)) {
54e99124
DG
724 retval = set_user(new);
725 if (retval < 0)
726 goto error;
727 }
1da177e4 728 }
d84f4f99 729 if (euid != (uid_t) -1)
a29c33f4 730 new->euid = keuid;
1da177e4 731 if (suid != (uid_t) -1)
a29c33f4 732 new->suid = ksuid;
d84f4f99 733 new->fsuid = new->euid;
1da177e4 734
d84f4f99
DH
735 retval = security_task_fix_setuid(new, old, LSM_SETID_RES);
736 if (retval < 0)
737 goto error;
1da177e4 738
905ae01c
AG
739 retval = set_cred_ucounts(new);
740 if (retval < 0)
741 goto error;
742
c923a8e7 743 flag_nproc_exceeded(new);
d84f4f99 744 return commit_creds(new);
1da177e4 745
d84f4f99
DH
746error:
747 abort_creds(new);
748 return retval;
1da177e4
LT
749}
750
e530dca5
DB
751SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid)
752{
753 return __sys_setresuid(ruid, euid, suid);
754}
755
a29c33f4 756SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp)
1da177e4 757{
86a264ab 758 const struct cred *cred = current_cred();
1da177e4 759 int retval;
a29c33f4
EB
760 uid_t ruid, euid, suid;
761
762 ruid = from_kuid_munged(cred->user_ns, cred->uid);
763 euid = from_kuid_munged(cred->user_ns, cred->euid);
764 suid = from_kuid_munged(cred->user_ns, cred->suid);
1da177e4 765
ec94fc3d 766 retval = put_user(ruid, ruidp);
767 if (!retval) {
768 retval = put_user(euid, euidp);
769 if (!retval)
770 return put_user(suid, suidp);
771 }
1da177e4
LT
772 return retval;
773}
774
775/*
776 * Same as above, but for rgid, egid, sgid.
777 */
e530dca5 778long __sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
1da177e4 779{
a29c33f4 780 struct user_namespace *ns = current_user_ns();
d84f4f99
DH
781 const struct cred *old;
782 struct cred *new;
1da177e4 783 int retval;
a29c33f4 784 kgid_t krgid, kegid, ksgid;
659c0ce1 785 bool rgid_new, egid_new, sgid_new;
a29c33f4
EB
786
787 krgid = make_kgid(ns, rgid);
788 kegid = make_kgid(ns, egid);
789 ksgid = make_kgid(ns, sgid);
790
791 if ((rgid != (gid_t) -1) && !gid_valid(krgid))
792 return -EINVAL;
793 if ((egid != (gid_t) -1) && !gid_valid(kegid))
794 return -EINVAL;
795 if ((sgid != (gid_t) -1) && !gid_valid(ksgid))
796 return -EINVAL;
1da177e4 797
659c0ce1
OM
798 old = current_cred();
799
800 /* check for no-op */
801 if ((rgid == (gid_t) -1 || gid_eq(krgid, old->gid)) &&
802 (egid == (gid_t) -1 || (gid_eq(kegid, old->egid) &&
803 gid_eq(kegid, old->fsgid))) &&
804 (sgid == (gid_t) -1 || gid_eq(ksgid, old->sgid)))
805 return 0;
806
807 rgid_new = rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) &&
808 !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid);
809 egid_new = egid != (gid_t) -1 && !gid_eq(kegid, old->gid) &&
810 !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid);
811 sgid_new = sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) &&
812 !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid);
813 if ((rgid_new || egid_new || sgid_new) &&
814 !ns_capable_setid(old->user_ns, CAP_SETGID))
815 return -EPERM;
816
d84f4f99
DH
817 new = prepare_creds();
818 if (!new)
819 return -ENOMEM;
d84f4f99 820
1da177e4 821 if (rgid != (gid_t) -1)
a29c33f4 822 new->gid = krgid;
d84f4f99 823 if (egid != (gid_t) -1)
a29c33f4 824 new->egid = kegid;
1da177e4 825 if (sgid != (gid_t) -1)
a29c33f4 826 new->sgid = ksgid;
d84f4f99 827 new->fsgid = new->egid;
1da177e4 828
39030e13
TC
829 retval = security_task_fix_setgid(new, old, LSM_SETID_RES);
830 if (retval < 0)
831 goto error;
832
d84f4f99
DH
833 return commit_creds(new);
834
835error:
836 abort_creds(new);
837 return retval;
1da177e4
LT
838}
839
e530dca5
DB
840SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid)
841{
842 return __sys_setresgid(rgid, egid, sgid);
843}
844
a29c33f4 845SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp)
1da177e4 846{
86a264ab 847 const struct cred *cred = current_cred();
1da177e4 848 int retval;
a29c33f4
EB
849 gid_t rgid, egid, sgid;
850
851 rgid = from_kgid_munged(cred->user_ns, cred->gid);
852 egid = from_kgid_munged(cred->user_ns, cred->egid);
853 sgid = from_kgid_munged(cred->user_ns, cred->sgid);
1da177e4 854
ec94fc3d 855 retval = put_user(rgid, rgidp);
856 if (!retval) {
857 retval = put_user(egid, egidp);
858 if (!retval)
859 retval = put_user(sgid, sgidp);
860 }
1da177e4
LT
861
862 return retval;
863}
864
865
866/*
867 * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This
868 * is used for "access()" and for the NFS daemon (letting nfsd stay at
869 * whatever uid it wants to). It normally shadows "euid", except when
870 * explicitly set by setfsuid() or for access..
871 */
e530dca5 872long __sys_setfsuid(uid_t uid)
1da177e4 873{
d84f4f99
DH
874 const struct cred *old;
875 struct cred *new;
876 uid_t old_fsuid;
a29c33f4
EB
877 kuid_t kuid;
878
879 old = current_cred();
880 old_fsuid = from_kuid_munged(old->user_ns, old->fsuid);
881
882 kuid = make_kuid(old->user_ns, uid);
883 if (!uid_valid(kuid))
884 return old_fsuid;
1da177e4 885
d84f4f99
DH
886 new = prepare_creds();
887 if (!new)
a29c33f4 888 return old_fsuid;
1da177e4 889
a29c33f4
EB
890 if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) ||
891 uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) ||
40852275 892 ns_capable_setid(old->user_ns, CAP_SETUID)) {
a29c33f4
EB
893 if (!uid_eq(kuid, old->fsuid)) {
894 new->fsuid = kuid;
d84f4f99
DH
895 if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0)
896 goto change_okay;
1da177e4 897 }
1da177e4
LT
898 }
899
d84f4f99
DH
900 abort_creds(new);
901 return old_fsuid;
1da177e4 902
d84f4f99
DH
903change_okay:
904 commit_creds(new);
1da177e4
LT
905 return old_fsuid;
906}
907
e530dca5
DB
908SYSCALL_DEFINE1(setfsuid, uid_t, uid)
909{
910 return __sys_setfsuid(uid);
911}
912
1da177e4 913/*
f42df9e6 914 * Samma på svenska..
1da177e4 915 */
e530dca5 916long __sys_setfsgid(gid_t gid)
1da177e4 917{
d84f4f99
DH
918 const struct cred *old;
919 struct cred *new;
920 gid_t old_fsgid;
a29c33f4
EB
921 kgid_t kgid;
922
923 old = current_cred();
924 old_fsgid = from_kgid_munged(old->user_ns, old->fsgid);
925
926 kgid = make_kgid(old->user_ns, gid);
927 if (!gid_valid(kgid))
928 return old_fsgid;
d84f4f99
DH
929
930 new = prepare_creds();
931 if (!new)
a29c33f4 932 return old_fsgid;
1da177e4 933
a29c33f4
EB
934 if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) ||
935 gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) ||
111767c1 936 ns_capable_setid(old->user_ns, CAP_SETGID)) {
a29c33f4
EB
937 if (!gid_eq(kgid, old->fsgid)) {
938 new->fsgid = kgid;
39030e13
TC
939 if (security_task_fix_setgid(new,old,LSM_SETID_FS) == 0)
940 goto change_okay;
1da177e4 941 }
1da177e4 942 }
d84f4f99 943
d84f4f99
DH
944 abort_creds(new);
945 return old_fsgid;
946
947change_okay:
948 commit_creds(new);
1da177e4
LT
949 return old_fsgid;
950}
e530dca5
DB
951
952SYSCALL_DEFINE1(setfsgid, gid_t, gid)
953{
954 return __sys_setfsgid(gid);
955}
2813893f 956#endif /* CONFIG_MULTIUSER */
1da177e4 957
4a22f166
SR
958/**
959 * sys_getpid - return the thread group id of the current process
960 *
961 * Note, despite the name, this returns the tgid not the pid. The tgid and
962 * the pid are identical unless CLONE_THREAD was specified on clone() in
963 * which case the tgid is the same in all threads of the same group.
964 *
965 * This is SMP safe as current->tgid does not change.
966 */
967SYSCALL_DEFINE0(getpid)
968{
969 return task_tgid_vnr(current);
970}
971
972/* Thread ID - the internal kernel "pid" */
973SYSCALL_DEFINE0(gettid)
974{
975 return task_pid_vnr(current);
976}
977
978/*
979 * Accessing ->real_parent is not SMP-safe, it could
980 * change from under us. However, we can use a stale
981 * value of ->real_parent under rcu_read_lock(), see
982 * release_task()->call_rcu(delayed_put_task_struct).
983 */
984SYSCALL_DEFINE0(getppid)
985{
986 int pid;
987
988 rcu_read_lock();
989 pid = task_tgid_vnr(rcu_dereference(current->real_parent));
990 rcu_read_unlock();
991
992 return pid;
993}
994
995SYSCALL_DEFINE0(getuid)
996{
997 /* Only we change this so SMP safe */
998 return from_kuid_munged(current_user_ns(), current_uid());
999}
1000
1001SYSCALL_DEFINE0(geteuid)
1002{
1003 /* Only we change this so SMP safe */
1004 return from_kuid_munged(current_user_ns(), current_euid());
1005}
1006
1007SYSCALL_DEFINE0(getgid)
1008{
1009 /* Only we change this so SMP safe */
1010 return from_kgid_munged(current_user_ns(), current_gid());
1011}
1012
1013SYSCALL_DEFINE0(getegid)
1014{
1015 /* Only we change this so SMP safe */
1016 return from_kgid_munged(current_user_ns(), current_egid());
1017}
1018
ca2406ed 1019static void do_sys_times(struct tms *tms)
f06febc9 1020{
5613fda9 1021 u64 tgutime, tgstime, cutime, cstime;
f06febc9 1022
e80d0a1a 1023 thread_group_cputime_adjusted(current, &tgutime, &tgstime);
f06febc9
FM
1024 cutime = current->signal->cutime;
1025 cstime = current->signal->cstime;
5613fda9
FW
1026 tms->tms_utime = nsec_to_clock_t(tgutime);
1027 tms->tms_stime = nsec_to_clock_t(tgstime);
1028 tms->tms_cutime = nsec_to_clock_t(cutime);
1029 tms->tms_cstime = nsec_to_clock_t(cstime);
f06febc9
FM
1030}
1031
58fd3aa2 1032SYSCALL_DEFINE1(times, struct tms __user *, tbuf)
1da177e4 1033{
1da177e4
LT
1034 if (tbuf) {
1035 struct tms tmp;
f06febc9
FM
1036
1037 do_sys_times(&tmp);
1da177e4
LT
1038 if (copy_to_user(tbuf, &tmp, sizeof(struct tms)))
1039 return -EFAULT;
1040 }
e3d5a27d 1041 force_successful_syscall_return();
1da177e4
LT
1042 return (long) jiffies_64_to_clock_t(get_jiffies_64());
1043}
1044
ca2406ed
AV
1045#ifdef CONFIG_COMPAT
1046static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
1047{
1048 return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
1049}
1050
1051COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
1052{
1053 if (tbuf) {
1054 struct tms tms;
1055 struct compat_tms tmp;
1056
1057 do_sys_times(&tms);
1058 /* Convert our struct tms to the compat version. */
1059 tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
1060 tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
1061 tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
1062 tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
1063 if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
1064 return -EFAULT;
1065 }
1066 force_successful_syscall_return();
1067 return compat_jiffies_to_clock_t(jiffies);
1068}
1069#endif
1070
1da177e4
LT
1071/*
1072 * This needs some heavy checking ...
1073 * I just haven't the stomach for it. I also don't fully
1074 * understand sessions/pgrp etc. Let somebody who does explain it.
1075 *
1076 * OK, I think I have the protection semantics right.... this is really
1077 * only important on a multi-user system anyway, to make sure one user
1078 * can't send a signal to a process owned by another. -TYT, 12/12/91
1079 *
98611e4e 1080 * !PF_FORKNOEXEC check to conform completely to POSIX.
1da177e4 1081 */
b290ebe2 1082SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid)
1da177e4
LT
1083{
1084 struct task_struct *p;
ee0acf90 1085 struct task_struct *group_leader = current->group_leader;
4e021306
ON
1086 struct pid *pgrp;
1087 int err;
1da177e4
LT
1088
1089 if (!pid)
b488893a 1090 pid = task_pid_vnr(group_leader);
1da177e4
LT
1091 if (!pgid)
1092 pgid = pid;
1093 if (pgid < 0)
1094 return -EINVAL;
950eaaca 1095 rcu_read_lock();
1da177e4
LT
1096
1097 /* From this point forward we keep holding onto the tasklist lock
1098 * so that our parent does not change from under us. -DaveM
1099 */
1100 write_lock_irq(&tasklist_lock);
1101
1102 err = -ESRCH;
4e021306 1103 p = find_task_by_vpid(pid);
1da177e4
LT
1104 if (!p)
1105 goto out;
1106
1107 err = -EINVAL;
1108 if (!thread_group_leader(p))
1109 goto out;
1110
4e021306 1111 if (same_thread_group(p->real_parent, group_leader)) {
1da177e4 1112 err = -EPERM;
41487c65 1113 if (task_session(p) != task_session(group_leader))
1da177e4
LT
1114 goto out;
1115 err = -EACCES;
98611e4e 1116 if (!(p->flags & PF_FORKNOEXEC))
1da177e4
LT
1117 goto out;
1118 } else {
1119 err = -ESRCH;
ee0acf90 1120 if (p != group_leader)
1da177e4
LT
1121 goto out;
1122 }
1123
1124 err = -EPERM;
1125 if (p->signal->leader)
1126 goto out;
1127
4e021306 1128 pgrp = task_pid(p);
1da177e4 1129 if (pgid != pid) {
b488893a 1130 struct task_struct *g;
1da177e4 1131
4e021306
ON
1132 pgrp = find_vpid(pgid);
1133 g = pid_task(pgrp, PIDTYPE_PGID);
41487c65 1134 if (!g || task_session(g) != task_session(group_leader))
f020bc46 1135 goto out;
1da177e4
LT
1136 }
1137
1da177e4
LT
1138 err = security_task_setpgid(p, pgid);
1139 if (err)
1140 goto out;
1141
1b0f7ffd 1142 if (task_pgrp(p) != pgrp)
83beaf3c 1143 change_pid(p, PIDTYPE_PGID, pgrp);
1da177e4
LT
1144
1145 err = 0;
1146out:
1147 /* All paths lead to here, thus we are safe. -DaveM */
1148 write_unlock_irq(&tasklist_lock);
950eaaca 1149 rcu_read_unlock();
1da177e4
LT
1150 return err;
1151}
1152
192c5807 1153static int do_getpgid(pid_t pid)
1da177e4 1154{
12a3de0a
ON
1155 struct task_struct *p;
1156 struct pid *grp;
1157 int retval;
1158
1159 rcu_read_lock();
756184b7 1160 if (!pid)
12a3de0a 1161 grp = task_pgrp(current);
756184b7 1162 else {
1da177e4 1163 retval = -ESRCH;
12a3de0a
ON
1164 p = find_task_by_vpid(pid);
1165 if (!p)
1166 goto out;
1167 grp = task_pgrp(p);
1168 if (!grp)
1169 goto out;
1170
1171 retval = security_task_getpgid(p);
1172 if (retval)
1173 goto out;
1da177e4 1174 }
12a3de0a
ON
1175 retval = pid_vnr(grp);
1176out:
1177 rcu_read_unlock();
1178 return retval;
1da177e4
LT
1179}
1180
192c5807
DB
1181SYSCALL_DEFINE1(getpgid, pid_t, pid)
1182{
1183 return do_getpgid(pid);
1184}
1185
1da177e4
LT
1186#ifdef __ARCH_WANT_SYS_GETPGRP
1187
dbf040d9 1188SYSCALL_DEFINE0(getpgrp)
1da177e4 1189{
192c5807 1190 return do_getpgid(0);
1da177e4
LT
1191}
1192
1193#endif
1194
dbf040d9 1195SYSCALL_DEFINE1(getsid, pid_t, pid)
1da177e4 1196{
1dd768c0
ON
1197 struct task_struct *p;
1198 struct pid *sid;
1199 int retval;
1200
1201 rcu_read_lock();
756184b7 1202 if (!pid)
1dd768c0 1203 sid = task_session(current);
756184b7 1204 else {
1da177e4 1205 retval = -ESRCH;
1dd768c0
ON
1206 p = find_task_by_vpid(pid);
1207 if (!p)
1208 goto out;
1209 sid = task_session(p);
1210 if (!sid)
1211 goto out;
1212
1213 retval = security_task_getsid(p);
1214 if (retval)
1215 goto out;
1da177e4 1216 }
1dd768c0
ON
1217 retval = pid_vnr(sid);
1218out:
1219 rcu_read_unlock();
1220 return retval;
1da177e4
LT
1221}
1222
81dabb46
ON
1223static void set_special_pids(struct pid *pid)
1224{
1225 struct task_struct *curr = current->group_leader;
1226
1227 if (task_session(curr) != pid)
1228 change_pid(curr, PIDTYPE_SID, pid);
1229
1230 if (task_pgrp(curr) != pid)
1231 change_pid(curr, PIDTYPE_PGID, pid);
1232}
1233
e2aaa9f4 1234int ksys_setsid(void)
1da177e4 1235{
e19f247a 1236 struct task_struct *group_leader = current->group_leader;
e4cc0a9c
ON
1237 struct pid *sid = task_pid(group_leader);
1238 pid_t session = pid_vnr(sid);
1da177e4
LT
1239 int err = -EPERM;
1240
1da177e4 1241 write_lock_irq(&tasklist_lock);
390e2ff0
EB
1242 /* Fail if I am already a session leader */
1243 if (group_leader->signal->leader)
1244 goto out;
1245
430c6231
ON
1246 /* Fail if a process group id already exists that equals the
1247 * proposed session id.
390e2ff0 1248 */
6806aac6 1249 if (pid_task(sid, PIDTYPE_PGID))
1da177e4
LT
1250 goto out;
1251
e19f247a 1252 group_leader->signal->leader = 1;
81dabb46 1253 set_special_pids(sid);
24ec839c 1254
9c9f4ded 1255 proc_clear_tty(group_leader);
24ec839c 1256
e4cc0a9c 1257 err = session;
1da177e4
LT
1258out:
1259 write_unlock_irq(&tasklist_lock);
5091faa4 1260 if (err > 0) {
0d0df599 1261 proc_sid_connector(group_leader);
5091faa4
MG
1262 sched_autogroup_create_attach(group_leader);
1263 }
1da177e4
LT
1264 return err;
1265}
1266
e2aaa9f4
DB
1267SYSCALL_DEFINE0(setsid)
1268{
1269 return ksys_setsid();
1270}
1271
1da177e4
LT
1272DECLARE_RWSEM(uts_sem);
1273
e28cbf22
CH
1274#ifdef COMPAT_UTS_MACHINE
1275#define override_architecture(name) \
46da2766 1276 (personality(current->personality) == PER_LINUX32 && \
e28cbf22
CH
1277 copy_to_user(name->machine, COMPAT_UTS_MACHINE, \
1278 sizeof(COMPAT_UTS_MACHINE)))
1279#else
1280#define override_architecture(name) 0
1281#endif
1282
be27425d
AK
1283/*
1284 * Work around broken programs that cannot handle "Linux 3.0".
1285 * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
b7285b42
JN
1286 * And we map 4.x and later versions to 2.6.60+x, so 4.0/5.0/6.0/... would be
1287 * 2.6.60.
be27425d 1288 */
2702b152 1289static int override_release(char __user *release, size_t len)
be27425d
AK
1290{
1291 int ret = 0;
be27425d
AK
1292
1293 if (current->personality & UNAME26) {
2702b152
KC
1294 const char *rest = UTS_RELEASE;
1295 char buf[65] = { 0 };
be27425d
AK
1296 int ndots = 0;
1297 unsigned v;
2702b152 1298 size_t copy;
be27425d
AK
1299
1300 while (*rest) {
1301 if (*rest == '.' && ++ndots >= 3)
1302 break;
1303 if (!isdigit(*rest) && *rest != '.')
1304 break;
1305 rest++;
1306 }
88a68672 1307 v = LINUX_VERSION_PATCHLEVEL + 60;
31fd84b9 1308 copy = clamp_t(size_t, len, 1, sizeof(buf));
2702b152
KC
1309 copy = scnprintf(buf, copy, "2.6.%u%s", v, rest);
1310 ret = copy_to_user(release, buf, copy + 1);
be27425d
AK
1311 }
1312 return ret;
1313}
1314
e48fbb69 1315SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
1da177e4 1316{
42a0cc34 1317 struct new_utsname tmp;
1da177e4
LT
1318
1319 down_read(&uts_sem);
42a0cc34 1320 memcpy(&tmp, utsname(), sizeof(tmp));
1da177e4 1321 up_read(&uts_sem);
42a0cc34
JH
1322 if (copy_to_user(name, &tmp, sizeof(tmp)))
1323 return -EFAULT;
e28cbf22 1324
42a0cc34
JH
1325 if (override_release(name->release, sizeof(name->release)))
1326 return -EFAULT;
1327 if (override_architecture(name))
1328 return -EFAULT;
1329 return 0;
1da177e4
LT
1330}
1331
5cacdb4a
CH
1332#ifdef __ARCH_WANT_SYS_OLD_UNAME
1333/*
1334 * Old cruft
1335 */
1336SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
1337{
42a0cc34 1338 struct old_utsname tmp;
5cacdb4a
CH
1339
1340 if (!name)
1341 return -EFAULT;
1342
1343 down_read(&uts_sem);
42a0cc34 1344 memcpy(&tmp, utsname(), sizeof(tmp));
5cacdb4a 1345 up_read(&uts_sem);
42a0cc34
JH
1346 if (copy_to_user(name, &tmp, sizeof(tmp)))
1347 return -EFAULT;
5cacdb4a 1348
42a0cc34
JH
1349 if (override_release(name->release, sizeof(name->release)))
1350 return -EFAULT;
1351 if (override_architecture(name))
1352 return -EFAULT;
1353 return 0;
5cacdb4a
CH
1354}
1355
1356SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
1357{
5e1aada0 1358 struct oldold_utsname tmp;
5cacdb4a
CH
1359
1360 if (!name)
1361 return -EFAULT;
5cacdb4a 1362
5e1aada0
JP
1363 memset(&tmp, 0, sizeof(tmp));
1364
5cacdb4a 1365 down_read(&uts_sem);
42a0cc34
JH
1366 memcpy(&tmp.sysname, &utsname()->sysname, __OLD_UTS_LEN);
1367 memcpy(&tmp.nodename, &utsname()->nodename, __OLD_UTS_LEN);
1368 memcpy(&tmp.release, &utsname()->release, __OLD_UTS_LEN);
1369 memcpy(&tmp.version, &utsname()->version, __OLD_UTS_LEN);
1370 memcpy(&tmp.machine, &utsname()->machine, __OLD_UTS_LEN);
5cacdb4a 1371 up_read(&uts_sem);
42a0cc34
JH
1372 if (copy_to_user(name, &tmp, sizeof(tmp)))
1373 return -EFAULT;
5cacdb4a 1374
42a0cc34
JH
1375 if (override_architecture(name))
1376 return -EFAULT;
1377 if (override_release(name->release, sizeof(name->release)))
1378 return -EFAULT;
1379 return 0;
5cacdb4a
CH
1380}
1381#endif
1382
5a8a82b1 1383SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
1da177e4
LT
1384{
1385 int errno;
1386 char tmp[__NEW_UTS_LEN];
1387
bb96a6f5 1388 if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1da177e4 1389 return -EPERM;
fc832ad3 1390
1da177e4
LT
1391 if (len < 0 || len > __NEW_UTS_LEN)
1392 return -EINVAL;
1da177e4
LT
1393 errno = -EFAULT;
1394 if (!copy_from_user(tmp, name, len)) {
42a0cc34 1395 struct new_utsname *u;
9679e4dd 1396
37608ba3 1397 add_device_randomness(tmp, len);
42a0cc34
JH
1398 down_write(&uts_sem);
1399 u = utsname();
9679e4dd
AM
1400 memcpy(u->nodename, tmp, len);
1401 memset(u->nodename + len, 0, sizeof(u->nodename) - len);
1da177e4 1402 errno = 0;
499eea6b 1403 uts_proc_notify(UTS_PROC_HOSTNAME);
42a0cc34 1404 up_write(&uts_sem);
1da177e4 1405 }
1da177e4
LT
1406 return errno;
1407}
1408
1409#ifdef __ARCH_WANT_SYS_GETHOSTNAME
1410
5a8a82b1 1411SYSCALL_DEFINE2(gethostname, char __user *, name, int, len)
1da177e4 1412{
42a0cc34 1413 int i;
9679e4dd 1414 struct new_utsname *u;
42a0cc34 1415 char tmp[__NEW_UTS_LEN + 1];
1da177e4
LT
1416
1417 if (len < 0)
1418 return -EINVAL;
1419 down_read(&uts_sem);
9679e4dd
AM
1420 u = utsname();
1421 i = 1 + strlen(u->nodename);
1da177e4
LT
1422 if (i > len)
1423 i = len;
42a0cc34 1424 memcpy(tmp, u->nodename, i);
1da177e4 1425 up_read(&uts_sem);
42a0cc34
JH
1426 if (copy_to_user(name, tmp, i))
1427 return -EFAULT;
1428 return 0;
1da177e4
LT
1429}
1430
1431#endif
1432
1433/*
1434 * Only setdomainname; getdomainname can be implemented by calling
1435 * uname()
1436 */
5a8a82b1 1437SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len)
1da177e4
LT
1438{
1439 int errno;
1440 char tmp[__NEW_UTS_LEN];
1441
fc832ad3 1442 if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1da177e4
LT
1443 return -EPERM;
1444 if (len < 0 || len > __NEW_UTS_LEN)
1445 return -EINVAL;
1446
1da177e4
LT
1447 errno = -EFAULT;
1448 if (!copy_from_user(tmp, name, len)) {
42a0cc34 1449 struct new_utsname *u;
9679e4dd 1450
37608ba3 1451 add_device_randomness(tmp, len);
42a0cc34
JH
1452 down_write(&uts_sem);
1453 u = utsname();
9679e4dd
AM
1454 memcpy(u->domainname, tmp, len);
1455 memset(u->domainname + len, 0, sizeof(u->domainname) - len);
1da177e4 1456 errno = 0;
499eea6b 1457 uts_proc_notify(UTS_PROC_DOMAINNAME);
42a0cc34 1458 up_write(&uts_sem);
1da177e4 1459 }
1da177e4
LT
1460 return errno;
1461}
1462
c57bef02
BR
1463/* make sure you are allowed to change @tsk limits before calling this */
1464static int do_prlimit(struct task_struct *tsk, unsigned int resource,
1465 struct rlimit *new_rlim, struct rlimit *old_rlim)
1466{
1467 struct rlimit *rlim;
1468 int retval = 0;
1469
1470 if (resource >= RLIM_NLIMITS)
1471 return -EINVAL;
73979060
GKH
1472 resource = array_index_nospec(resource, RLIM_NLIMITS);
1473
c57bef02
BR
1474 if (new_rlim) {
1475 if (new_rlim->rlim_cur > new_rlim->rlim_max)
1476 return -EINVAL;
1477 if (resource == RLIMIT_NOFILE &&
1478 new_rlim->rlim_max > sysctl_nr_open)
1479 return -EPERM;
1480 }
1481
18c91bb2 1482 /* Holding a refcount on tsk protects tsk->signal from disappearing. */
c57bef02
BR
1483 rlim = tsk->signal->rlim + resource;
1484 task_lock(tsk->group_leader);
1485 if (new_rlim) {
1486 /*
1487 * Keep the capable check against init_user_ns until cgroups can
1488 * contain all limits.
1489 */
1490 if (new_rlim->rlim_max > rlim->rlim_max &&
1491 !capable(CAP_SYS_RESOURCE))
1492 retval = -EPERM;
1493 if (!retval)
1494 retval = security_task_setrlimit(tsk, resource, new_rlim);
1495 }
1496 if (!retval) {
1497 if (old_rlim)
1498 *old_rlim = *rlim;
1499 if (new_rlim)
1500 *rlim = *new_rlim;
1501 }
1502 task_unlock(tsk->group_leader);
1503
1504 /*
1505 * RLIMIT_CPU handling. Arm the posix CPU timer if the limit is not
1506 * infinite. In case of RLIM_INFINITY the posix CPU timer code
1507 * ignores the rlimit.
1508 */
1509 if (!retval && new_rlim && resource == RLIMIT_CPU &&
1510 new_rlim->rlim_cur != RLIM_INFINITY &&
18c91bb2
BR
1511 IS_ENABLED(CONFIG_POSIX_TIMERS)) {
1512 /*
1513 * update_rlimit_cpu can fail if the task is exiting, but there
1514 * may be other tasks in the thread group that are not exiting,
1515 * and they need their cpu timers adjusted.
1516 *
1517 * The group_leader is the last task to be released, so if we
1518 * cannot update_rlimit_cpu on it, then the entire process is
1519 * exiting and we do not need to update at all.
1520 */
1521 update_rlimit_cpu(tsk->group_leader, new_rlim->rlim_cur);
1522 }
1523
c57bef02
BR
1524 return retval;
1525}
1526
e48fbb69 1527SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1da177e4 1528{
b9518345
JS
1529 struct rlimit value;
1530 int ret;
1531
1532 ret = do_prlimit(current, resource, NULL, &value);
1533 if (!ret)
1534 ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0;
1535
1536 return ret;
1da177e4
LT
1537}
1538
d9e968cb
AV
1539#ifdef CONFIG_COMPAT
1540
1541COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
1542 struct compat_rlimit __user *, rlim)
1543{
1544 struct rlimit r;
1545 struct compat_rlimit r32;
1546
1547 if (copy_from_user(&r32, rlim, sizeof(struct compat_rlimit)))
1548 return -EFAULT;
1549
1550 if (r32.rlim_cur == COMPAT_RLIM_INFINITY)
1551 r.rlim_cur = RLIM_INFINITY;
1552 else
1553 r.rlim_cur = r32.rlim_cur;
1554 if (r32.rlim_max == COMPAT_RLIM_INFINITY)
1555 r.rlim_max = RLIM_INFINITY;
1556 else
1557 r.rlim_max = r32.rlim_max;
1558 return do_prlimit(current, resource, &r, NULL);
1559}
1560
1561COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
1562 struct compat_rlimit __user *, rlim)
1563{
1564 struct rlimit r;
1565 int ret;
1566
1567 ret = do_prlimit(current, resource, NULL, &r);
1568 if (!ret) {
58c7ffc0 1569 struct compat_rlimit r32;
d9e968cb
AV
1570 if (r.rlim_cur > COMPAT_RLIM_INFINITY)
1571 r32.rlim_cur = COMPAT_RLIM_INFINITY;
1572 else
1573 r32.rlim_cur = r.rlim_cur;
1574 if (r.rlim_max > COMPAT_RLIM_INFINITY)
1575 r32.rlim_max = COMPAT_RLIM_INFINITY;
1576 else
1577 r32.rlim_max = r.rlim_max;
1578
1579 if (copy_to_user(rlim, &r32, sizeof(struct compat_rlimit)))
1580 return -EFAULT;
1581 }
1582 return ret;
1583}
1584
1585#endif
1586
1da177e4
LT
1587#ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
1588
1589/*
1590 * Back compatibility for getrlimit. Needed for some apps.
1591 */
e48fbb69
HC
1592SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1593 struct rlimit __user *, rlim)
1da177e4
LT
1594{
1595 struct rlimit x;
1596 if (resource >= RLIM_NLIMITS)
1597 return -EINVAL;
1598
23d6aef7 1599 resource = array_index_nospec(resource, RLIM_NLIMITS);
1da177e4
LT
1600 task_lock(current->group_leader);
1601 x = current->signal->rlim[resource];
1602 task_unlock(current->group_leader);
756184b7 1603 if (x.rlim_cur > 0x7FFFFFFF)
1da177e4 1604 x.rlim_cur = 0x7FFFFFFF;
756184b7 1605 if (x.rlim_max > 0x7FFFFFFF)
1da177e4 1606 x.rlim_max = 0x7FFFFFFF;
ec94fc3d 1607 return copy_to_user(rlim, &x, sizeof(x)) ? -EFAULT : 0;
1da177e4
LT
1608}
1609
613763a1
AV
1610#ifdef CONFIG_COMPAT
1611COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1612 struct compat_rlimit __user *, rlim)
1613{
1614 struct rlimit r;
1615
1616 if (resource >= RLIM_NLIMITS)
1617 return -EINVAL;
1618
23d6aef7 1619 resource = array_index_nospec(resource, RLIM_NLIMITS);
613763a1
AV
1620 task_lock(current->group_leader);
1621 r = current->signal->rlim[resource];
1622 task_unlock(current->group_leader);
1623 if (r.rlim_cur > 0x7FFFFFFF)
1624 r.rlim_cur = 0x7FFFFFFF;
1625 if (r.rlim_max > 0x7FFFFFFF)
1626 r.rlim_max = 0x7FFFFFFF;
1627
1628 if (put_user(r.rlim_cur, &rlim->rlim_cur) ||
1629 put_user(r.rlim_max, &rlim->rlim_max))
1630 return -EFAULT;
1631 return 0;
1632}
1633#endif
1634
1da177e4
LT
1635#endif
1636
c022a0ac
JS
1637static inline bool rlim64_is_infinity(__u64 rlim64)
1638{
1639#if BITS_PER_LONG < 64
1640 return rlim64 >= ULONG_MAX;
1641#else
1642 return rlim64 == RLIM64_INFINITY;
1643#endif
1644}
1645
1646static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64)
1647{
1648 if (rlim->rlim_cur == RLIM_INFINITY)
1649 rlim64->rlim_cur = RLIM64_INFINITY;
1650 else
1651 rlim64->rlim_cur = rlim->rlim_cur;
1652 if (rlim->rlim_max == RLIM_INFINITY)
1653 rlim64->rlim_max = RLIM64_INFINITY;
1654 else
1655 rlim64->rlim_max = rlim->rlim_max;
1656}
1657
1658static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim)
1659{
1660 if (rlim64_is_infinity(rlim64->rlim_cur))
1661 rlim->rlim_cur = RLIM_INFINITY;
1662 else
1663 rlim->rlim_cur = (unsigned long)rlim64->rlim_cur;
1664 if (rlim64_is_infinity(rlim64->rlim_max))
1665 rlim->rlim_max = RLIM_INFINITY;
1666 else
1667 rlim->rlim_max = (unsigned long)rlim64->rlim_max;
1668}
1669
c022a0ac 1670/* rcu lock must be held */
791ec491
SS
1671static int check_prlimit_permission(struct task_struct *task,
1672 unsigned int flags)
c022a0ac
JS
1673{
1674 const struct cred *cred = current_cred(), *tcred;
791ec491 1675 bool id_match;
c022a0ac 1676
fc832ad3
SH
1677 if (current == task)
1678 return 0;
c022a0ac 1679
fc832ad3 1680 tcred = __task_cred(task);
791ec491
SS
1681 id_match = (uid_eq(cred->uid, tcred->euid) &&
1682 uid_eq(cred->uid, tcred->suid) &&
1683 uid_eq(cred->uid, tcred->uid) &&
1684 gid_eq(cred->gid, tcred->egid) &&
1685 gid_eq(cred->gid, tcred->sgid) &&
1686 gid_eq(cred->gid, tcred->gid));
1687 if (!id_match && !ns_capable(tcred->user_ns, CAP_SYS_RESOURCE))
1688 return -EPERM;
fc832ad3 1689
791ec491 1690 return security_task_prlimit(cred, tcred, flags);
c022a0ac
JS
1691}
1692
1693SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource,
1694 const struct rlimit64 __user *, new_rlim,
1695 struct rlimit64 __user *, old_rlim)
1696{
1697 struct rlimit64 old64, new64;
1698 struct rlimit old, new;
1699 struct task_struct *tsk;
791ec491 1700 unsigned int checkflags = 0;
c022a0ac
JS
1701 int ret;
1702
791ec491
SS
1703 if (old_rlim)
1704 checkflags |= LSM_PRLIMIT_READ;
1705
c022a0ac
JS
1706 if (new_rlim) {
1707 if (copy_from_user(&new64, new_rlim, sizeof(new64)))
1708 return -EFAULT;
1709 rlim64_to_rlim(&new64, &new);
791ec491 1710 checkflags |= LSM_PRLIMIT_WRITE;
c022a0ac
JS
1711 }
1712
1713 rcu_read_lock();
1714 tsk = pid ? find_task_by_vpid(pid) : current;
1715 if (!tsk) {
1716 rcu_read_unlock();
1717 return -ESRCH;
1718 }
791ec491 1719 ret = check_prlimit_permission(tsk, checkflags);
c022a0ac
JS
1720 if (ret) {
1721 rcu_read_unlock();
1722 return ret;
1723 }
1724 get_task_struct(tsk);
1725 rcu_read_unlock();
1726
1727 ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL,
1728 old_rlim ? &old : NULL);
1729
1730 if (!ret && old_rlim) {
1731 rlim_to_rlim64(&old, &old64);
1732 if (copy_to_user(old_rlim, &old64, sizeof(old64)))
1733 ret = -EFAULT;
1734 }
1735
1736 put_task_struct(tsk);
1737 return ret;
1738}
1739
7855c35d
JS
1740SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1741{
1742 struct rlimit new_rlim;
1743
1744 if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
1745 return -EFAULT;
5b41535a 1746 return do_prlimit(current, resource, &new_rlim, NULL);
7855c35d
JS
1747}
1748
1da177e4
LT
1749/*
1750 * It would make sense to put struct rusage in the task_struct,
1751 * except that would make the task_struct be *really big*. After
1752 * task_struct gets moved into malloc'ed memory, it would
1753 * make sense to do this. It will make moving the rest of the information
1754 * a lot simpler! (Which we're not doing right now because we're not
1755 * measuring them yet).
1756 *
1da177e4
LT
1757 * When sampling multiple threads for RUSAGE_SELF, under SMP we might have
1758 * races with threads incrementing their own counters. But since word
1759 * reads are atomic, we either get new values or old values and we don't
1760 * care which for the sums. We always take the siglock to protect reading
1761 * the c* fields from p->signal from races with exit.c updating those
1762 * fields when reaping, so a sample either gets all the additions of a
1763 * given child after it's reaped, or none so this sample is before reaping.
2dd0ebcd 1764 *
de047c1b
RT
1765 * Locking:
1766 * We need to take the siglock for CHILDEREN, SELF and BOTH
1767 * for the cases current multithreaded, non-current single threaded
1768 * non-current multithreaded. Thread traversal is now safe with
1769 * the siglock held.
1770 * Strictly speaking, we donot need to take the siglock if we are current and
1771 * single threaded, as no one else can take our signal_struct away, no one
1772 * else can reap the children to update signal->c* counters, and no one else
1773 * can race with the signal-> fields. If we do not take any lock, the
1774 * signal-> fields could be read out of order while another thread was just
1775 * exiting. So we should place a read memory barrier when we avoid the lock.
1776 * On the writer side, write memory barrier is implied in __exit_signal
1777 * as __exit_signal releases the siglock spinlock after updating the signal->
1778 * fields. But we don't do this yet to keep things simple.
2dd0ebcd 1779 *
1da177e4
LT
1780 */
1781
f06febc9 1782static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r)
679c9cd4 1783{
679c9cd4
SK
1784 r->ru_nvcsw += t->nvcsw;
1785 r->ru_nivcsw += t->nivcsw;
1786 r->ru_minflt += t->min_flt;
1787 r->ru_majflt += t->maj_flt;
1788 r->ru_inblock += task_io_get_inblock(t);
1789 r->ru_oublock += task_io_get_oublock(t);
1790}
1791
ce72a16f 1792void getrusage(struct task_struct *p, int who, struct rusage *r)
1da177e4
LT
1793{
1794 struct task_struct *t;
1795 unsigned long flags;
5613fda9 1796 u64 tgutime, tgstime, utime, stime;
daa694e4
ON
1797 unsigned long maxrss;
1798 struct mm_struct *mm;
c7ac8231 1799 struct signal_struct *sig = p->signal;
f7ec1cd5 1800 unsigned int seq = 0;
1da177e4 1801
f7ec1cd5 1802retry:
daa694e4 1803 memset(r, 0, sizeof(*r));
64861634 1804 utime = stime = 0;
daa694e4 1805 maxrss = 0;
1da177e4 1806
679c9cd4 1807 if (who == RUSAGE_THREAD) {
e80d0a1a 1808 task_cputime_adjusted(current, &utime, &stime);
f06febc9 1809 accumulate_thread_rusage(p, r);
c7ac8231 1810 maxrss = sig->maxrss;
daa694e4 1811 goto out_thread;
679c9cd4
SK
1812 }
1813
f7ec1cd5 1814 flags = read_seqbegin_or_lock_irqsave(&sig->stats_lock, &seq);
0f59cc4a 1815
1da177e4 1816 switch (who) {
ec94fc3d 1817 case RUSAGE_BOTH:
1818 case RUSAGE_CHILDREN:
c7ac8231
ON
1819 utime = sig->cutime;
1820 stime = sig->cstime;
1821 r->ru_nvcsw = sig->cnvcsw;
1822 r->ru_nivcsw = sig->cnivcsw;
1823 r->ru_minflt = sig->cmin_flt;
1824 r->ru_majflt = sig->cmaj_flt;
1825 r->ru_inblock = sig->cinblock;
1826 r->ru_oublock = sig->coublock;
1827 maxrss = sig->cmaxrss;
ec94fc3d 1828
1829 if (who == RUSAGE_CHILDREN)
1da177e4 1830 break;
df561f66 1831 fallthrough;
0f59cc4a 1832
ec94fc3d 1833 case RUSAGE_SELF:
c7ac8231
ON
1834 r->ru_nvcsw += sig->nvcsw;
1835 r->ru_nivcsw += sig->nivcsw;
1836 r->ru_minflt += sig->min_flt;
1837 r->ru_majflt += sig->maj_flt;
1838 r->ru_inblock += sig->inblock;
1839 r->ru_oublock += sig->oublock;
1840 if (maxrss < sig->maxrss)
1841 maxrss = sig->maxrss;
f7ec1cd5
ON
1842
1843 rcu_read_lock();
13b7bc60 1844 __for_each_thread(sig, t)
ec94fc3d 1845 accumulate_thread_rusage(t, r);
f7ec1cd5
ON
1846 rcu_read_unlock();
1847
ec94fc3d 1848 break;
1849
1850 default:
1851 BUG();
1da177e4 1852 }
f7ec1cd5
ON
1853
1854 if (need_seqretry(&sig->stats_lock, seq)) {
1855 seq = 1;
1856 goto retry;
1857 }
1858 done_seqretry_irqrestore(&sig->stats_lock, seq, flags);
de047c1b 1859
daa694e4
ON
1860 if (who == RUSAGE_CHILDREN)
1861 goto out_children;
1f10206c 1862
daa694e4
ON
1863 thread_group_cputime_adjusted(p, &tgutime, &tgstime);
1864 utime += tgutime;
1865 stime += tgstime;
ec94fc3d 1866
daa694e4
ON
1867out_thread:
1868 mm = get_task_mm(p);
1869 if (mm) {
1870 setmax_mm_hiwater_rss(&maxrss, mm);
1871 mmput(mm);
1f10206c 1872 }
daa694e4
ON
1873
1874out_children:
1f10206c 1875 r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */
daa694e4
ON
1876 r->ru_utime = ns_to_kernel_old_timeval(utime);
1877 r->ru_stime = ns_to_kernel_old_timeval(stime);
1da177e4
LT
1878}
1879
ce72a16f 1880SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru)
1da177e4
LT
1881{
1882 struct rusage r;
ec94fc3d 1883
679c9cd4
SK
1884 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1885 who != RUSAGE_THREAD)
1da177e4 1886 return -EINVAL;
ce72a16f
AV
1887
1888 getrusage(current, who, &r);
1889 return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
1da177e4
LT
1890}
1891
8d2d5c4a
AV
1892#ifdef CONFIG_COMPAT
1893COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru)
1894{
1895 struct rusage r;
1896
1897 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1898 who != RUSAGE_THREAD)
1899 return -EINVAL;
1900
ce72a16f 1901 getrusage(current, who, &r);
8d2d5c4a
AV
1902 return put_compat_rusage(&r, ru);
1903}
1904#endif
1905
e48fbb69 1906SYSCALL_DEFINE1(umask, int, mask)
1da177e4
LT
1907{
1908 mask = xchg(&current->fs->umask, mask & S_IRWXUGO);
1909 return mask;
1910}
3b7391de 1911
6e399cd1 1912static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
b32dfe37 1913{
2903ff01 1914 struct fd exe;
496ad9aa 1915 struct inode *inode;
2903ff01 1916 int err;
b32dfe37 1917
2903ff01
AV
1918 exe = fdget(fd);
1919 if (!exe.file)
b32dfe37
CG
1920 return -EBADF;
1921
496ad9aa 1922 inode = file_inode(exe.file);
b32dfe37
CG
1923
1924 /*
1925 * Because the original mm->exe_file points to executable file, make
1926 * sure that this one is executable as well, to avoid breaking an
1927 * overall picture.
1928 */
1929 err = -EACCES;
90f8572b 1930 if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path))
b32dfe37
CG
1931 goto exit;
1932
02f92b38 1933 err = file_permission(exe.file, MAY_EXEC);
b32dfe37
CG
1934 if (err)
1935 goto exit;
1936
35d7bdc8 1937 err = replace_mm_exe_file(mm, exe.file);
b32dfe37 1938exit:
2903ff01 1939 fdput(exe);
b32dfe37
CG
1940 return err;
1941}
1942
f606b77f 1943/*
11bbd8b4
MK
1944 * Check arithmetic relations of passed addresses.
1945 *
f606b77f
CG
1946 * WARNING: we don't require any capability here so be very careful
1947 * in what is allowed for modification from userspace.
1948 */
11bbd8b4 1949static int validate_prctl_map_addr(struct prctl_mm_map *prctl_map)
f606b77f
CG
1950{
1951 unsigned long mmap_max_addr = TASK_SIZE;
f606b77f
CG
1952 int error = -EINVAL, i;
1953
1954 static const unsigned char offsets[] = {
1955 offsetof(struct prctl_mm_map, start_code),
1956 offsetof(struct prctl_mm_map, end_code),
1957 offsetof(struct prctl_mm_map, start_data),
1958 offsetof(struct prctl_mm_map, end_data),
1959 offsetof(struct prctl_mm_map, start_brk),
1960 offsetof(struct prctl_mm_map, brk),
1961 offsetof(struct prctl_mm_map, start_stack),
1962 offsetof(struct prctl_mm_map, arg_start),
1963 offsetof(struct prctl_mm_map, arg_end),
1964 offsetof(struct prctl_mm_map, env_start),
1965 offsetof(struct prctl_mm_map, env_end),
1966 };
1967
1968 /*
1969 * Make sure the members are not somewhere outside
1970 * of allowed address space.
1971 */
1972 for (i = 0; i < ARRAY_SIZE(offsets); i++) {
1973 u64 val = *(u64 *)((char *)prctl_map + offsets[i]);
1974
1975 if ((unsigned long)val >= mmap_max_addr ||
1976 (unsigned long)val < mmap_min_addr)
1977 goto out;
1978 }
1979
1980 /*
1981 * Make sure the pairs are ordered.
1982 */
1983#define __prctl_check_order(__m1, __op, __m2) \
1984 ((unsigned long)prctl_map->__m1 __op \
1985 (unsigned long)prctl_map->__m2) ? 0 : -EINVAL
1986 error = __prctl_check_order(start_code, <, end_code);
a9e73998 1987 error |= __prctl_check_order(start_data,<=, end_data);
f606b77f
CG
1988 error |= __prctl_check_order(start_brk, <=, brk);
1989 error |= __prctl_check_order(arg_start, <=, arg_end);
1990 error |= __prctl_check_order(env_start, <=, env_end);
1991 if (error)
1992 goto out;
1993#undef __prctl_check_order
1994
1995 error = -EINVAL;
1996
f606b77f
CG
1997 /*
1998 * Neither we should allow to override limits if they set.
1999 */
2000 if (check_data_rlimit(rlimit(RLIMIT_DATA), prctl_map->brk,
2001 prctl_map->start_brk, prctl_map->end_data,
2002 prctl_map->start_data))
2003 goto out;
2004
f606b77f
CG
2005 error = 0;
2006out:
2007 return error;
2008}
2009
4a00e9df 2010#ifdef CONFIG_CHECKPOINT_RESTORE
f606b77f
CG
2011static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size)
2012{
2013 struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, };
2014 unsigned long user_auxv[AT_VECTOR_SIZE];
2015 struct mm_struct *mm = current->mm;
2016 int error;
2017
2018 BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
2019 BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256);
2020
2021 if (opt == PR_SET_MM_MAP_SIZE)
2022 return put_user((unsigned int)sizeof(prctl_map),
2023 (unsigned int __user *)addr);
2024
2025 if (data_size != sizeof(prctl_map))
2026 return -EINVAL;
2027
2028 if (copy_from_user(&prctl_map, addr, sizeof(prctl_map)))
2029 return -EFAULT;
2030
11bbd8b4 2031 error = validate_prctl_map_addr(&prctl_map);
f606b77f
CG
2032 if (error)
2033 return error;
2034
2035 if (prctl_map.auxv_size) {
11bbd8b4
MK
2036 /*
2037 * Someone is trying to cheat the auxv vector.
2038 */
2039 if (!prctl_map.auxv ||
2040 prctl_map.auxv_size > sizeof(mm->saved_auxv))
2041 return -EINVAL;
2042
f606b77f
CG
2043 memset(user_auxv, 0, sizeof(user_auxv));
2044 if (copy_from_user(user_auxv,
2045 (const void __user *)prctl_map.auxv,
2046 prctl_map.auxv_size))
2047 return -EFAULT;
2048
2049 /* Last entry must be AT_NULL as specification requires */
2050 user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL;
2051 user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL;
2052 }
2053
ddf1d398 2054 if (prctl_map.exe_fd != (u32)-1) {
11bbd8b4 2055 /*
ebd6de68
NV
2056 * Check if the current user is checkpoint/restore capable.
2057 * At the time of this writing, it checks for CAP_SYS_ADMIN
2058 * or CAP_CHECKPOINT_RESTORE.
2059 * Note that a user with access to ptrace can masquerade an
2060 * arbitrary program as any executable, even setuid ones.
2061 * This may have implications in the tomoyo subsystem.
11bbd8b4 2062 */
ebd6de68 2063 if (!checkpoint_restore_ns_capable(current_user_ns()))
227175b2 2064 return -EPERM;
11bbd8b4 2065
6e399cd1 2066 error = prctl_set_mm_exe_file(mm, prctl_map.exe_fd);
ddf1d398
MG
2067 if (error)
2068 return error;
2069 }
2070
88aa7cc6 2071 /*
5afe69c2 2072 * arg_lock protects concurrent updates but we still need mmap_lock for
88aa7cc6
YS
2073 * read to exclude races with sys_brk.
2074 */
d8ed45c5 2075 mmap_read_lock(mm);
f606b77f
CG
2076
2077 /*
2078 * We don't validate if these members are pointing to
2079 * real present VMAs because application may have correspond
2080 * VMAs already unmapped and kernel uses these members for statistics
2081 * output in procfs mostly, except
2082 *
15ec0fcf 2083 * - @start_brk/@brk which are used in do_brk_flags but kernel lookups
5afe69c2 2084 * for VMAs when updating these members so anything wrong written
f606b77f
CG
2085 * here cause kernel to swear at userspace program but won't lead
2086 * to any problem in kernel itself
2087 */
2088
88aa7cc6 2089 spin_lock(&mm->arg_lock);
f606b77f
CG
2090 mm->start_code = prctl_map.start_code;
2091 mm->end_code = prctl_map.end_code;
2092 mm->start_data = prctl_map.start_data;
2093 mm->end_data = prctl_map.end_data;
2094 mm->start_brk = prctl_map.start_brk;
2095 mm->brk = prctl_map.brk;
2096 mm->start_stack = prctl_map.start_stack;
2097 mm->arg_start = prctl_map.arg_start;
2098 mm->arg_end = prctl_map.arg_end;
2099 mm->env_start = prctl_map.env_start;
2100 mm->env_end = prctl_map.env_end;
88aa7cc6 2101 spin_unlock(&mm->arg_lock);
f606b77f
CG
2102
2103 /*
2104 * Note this update of @saved_auxv is lockless thus
2105 * if someone reads this member in procfs while we're
2106 * updating -- it may get partly updated results. It's
2107 * known and acceptable trade off: we leave it as is to
2108 * not introduce additional locks here making the kernel
2109 * more complex.
2110 */
2111 if (prctl_map.auxv_size)
2112 memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv));
2113
d8ed45c5 2114 mmap_read_unlock(mm);
ddf1d398 2115 return 0;
f606b77f
CG
2116}
2117#endif /* CONFIG_CHECKPOINT_RESTORE */
2118
4a00e9df
AD
2119static int prctl_set_auxv(struct mm_struct *mm, unsigned long addr,
2120 unsigned long len)
2121{
2122 /*
2123 * This doesn't move the auxiliary vector itself since it's pinned to
2124 * mm_struct, but it permits filling the vector with new values. It's
2125 * up to the caller to provide sane values here, otherwise userspace
2126 * tools which use this vector might be unhappy.
2127 */
c995f12a 2128 unsigned long user_auxv[AT_VECTOR_SIZE] = {};
4a00e9df
AD
2129
2130 if (len > sizeof(user_auxv))
2131 return -EINVAL;
2132
2133 if (copy_from_user(user_auxv, (const void __user *)addr, len))
2134 return -EFAULT;
2135
2136 /* Make sure the last entry is always AT_NULL */
2137 user_auxv[AT_VECTOR_SIZE - 2] = 0;
2138 user_auxv[AT_VECTOR_SIZE - 1] = 0;
2139
2140 BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
2141
2142 task_lock(current);
2143 memcpy(mm->saved_auxv, user_auxv, len);
2144 task_unlock(current);
2145
2146 return 0;
2147}
2148
028ee4be
CG
2149static int prctl_set_mm(int opt, unsigned long addr,
2150 unsigned long arg4, unsigned long arg5)
2151{
028ee4be 2152 struct mm_struct *mm = current->mm;
11bbd8b4
MK
2153 struct prctl_mm_map prctl_map = {
2154 .auxv = NULL,
2155 .auxv_size = 0,
2156 .exe_fd = -1,
2157 };
fe8c7f5c
CG
2158 struct vm_area_struct *vma;
2159 int error;
028ee4be 2160
f606b77f
CG
2161 if (arg5 || (arg4 && (opt != PR_SET_MM_AUXV &&
2162 opt != PR_SET_MM_MAP &&
2163 opt != PR_SET_MM_MAP_SIZE)))
028ee4be
CG
2164 return -EINVAL;
2165
f606b77f
CG
2166#ifdef CONFIG_CHECKPOINT_RESTORE
2167 if (opt == PR_SET_MM_MAP || opt == PR_SET_MM_MAP_SIZE)
2168 return prctl_set_mm_map(opt, (const void __user *)addr, arg4);
2169#endif
2170
79f0713d 2171 if (!capable(CAP_SYS_RESOURCE))
028ee4be
CG
2172 return -EPERM;
2173
6e399cd1
DB
2174 if (opt == PR_SET_MM_EXE_FILE)
2175 return prctl_set_mm_exe_file(mm, (unsigned int)addr);
b32dfe37 2176
4a00e9df
AD
2177 if (opt == PR_SET_MM_AUXV)
2178 return prctl_set_auxv(mm, addr, arg4);
2179
1ad75b9e 2180 if (addr >= TASK_SIZE || addr < mmap_min_addr)
028ee4be
CG
2181 return -EINVAL;
2182
fe8c7f5c
CG
2183 error = -EINVAL;
2184
bc81426f 2185 /*
5afe69c2 2186 * arg_lock protects concurrent updates of arg boundaries, we need
c1e8d7c6 2187 * mmap_lock for a) concurrent sys_brk, b) finding VMA for addr
bc81426f
MK
2188 * validation.
2189 */
d8ed45c5 2190 mmap_read_lock(mm);
028ee4be
CG
2191 vma = find_vma(mm, addr);
2192
bc81426f 2193 spin_lock(&mm->arg_lock);
4a00e9df
AD
2194 prctl_map.start_code = mm->start_code;
2195 prctl_map.end_code = mm->end_code;
2196 prctl_map.start_data = mm->start_data;
2197 prctl_map.end_data = mm->end_data;
2198 prctl_map.start_brk = mm->start_brk;
2199 prctl_map.brk = mm->brk;
2200 prctl_map.start_stack = mm->start_stack;
2201 prctl_map.arg_start = mm->arg_start;
2202 prctl_map.arg_end = mm->arg_end;
2203 prctl_map.env_start = mm->env_start;
2204 prctl_map.env_end = mm->env_end;
4a00e9df 2205
028ee4be
CG
2206 switch (opt) {
2207 case PR_SET_MM_START_CODE:
4a00e9df 2208 prctl_map.start_code = addr;
fe8c7f5c 2209 break;
028ee4be 2210 case PR_SET_MM_END_CODE:
4a00e9df 2211 prctl_map.end_code = addr;
028ee4be 2212 break;
028ee4be 2213 case PR_SET_MM_START_DATA:
4a00e9df 2214 prctl_map.start_data = addr;
028ee4be 2215 break;
fe8c7f5c 2216 case PR_SET_MM_END_DATA:
4a00e9df
AD
2217 prctl_map.end_data = addr;
2218 break;
2219 case PR_SET_MM_START_STACK:
2220 prctl_map.start_stack = addr;
028ee4be 2221 break;
028ee4be 2222 case PR_SET_MM_START_BRK:
4a00e9df 2223 prctl_map.start_brk = addr;
028ee4be 2224 break;
028ee4be 2225 case PR_SET_MM_BRK:
4a00e9df 2226 prctl_map.brk = addr;
028ee4be 2227 break;
4a00e9df
AD
2228 case PR_SET_MM_ARG_START:
2229 prctl_map.arg_start = addr;
2230 break;
2231 case PR_SET_MM_ARG_END:
2232 prctl_map.arg_end = addr;
2233 break;
2234 case PR_SET_MM_ENV_START:
2235 prctl_map.env_start = addr;
2236 break;
2237 case PR_SET_MM_ENV_END:
2238 prctl_map.env_end = addr;
2239 break;
2240 default:
2241 goto out;
2242 }
2243
11bbd8b4 2244 error = validate_prctl_map_addr(&prctl_map);
4a00e9df
AD
2245 if (error)
2246 goto out;
028ee4be 2247
4a00e9df 2248 switch (opt) {
fe8c7f5c
CG
2249 /*
2250 * If command line arguments and environment
2251 * are placed somewhere else on stack, we can
2252 * set them up here, ARG_START/END to setup
5afe69c2 2253 * command line arguments and ENV_START/END
fe8c7f5c
CG
2254 * for environment.
2255 */
2256 case PR_SET_MM_START_STACK:
2257 case PR_SET_MM_ARG_START:
2258 case PR_SET_MM_ARG_END:
2259 case PR_SET_MM_ENV_START:
2260 case PR_SET_MM_ENV_END:
2261 if (!vma) {
2262 error = -EFAULT;
2263 goto out;
2264 }
028ee4be
CG
2265 }
2266
4a00e9df
AD
2267 mm->start_code = prctl_map.start_code;
2268 mm->end_code = prctl_map.end_code;
2269 mm->start_data = prctl_map.start_data;
2270 mm->end_data = prctl_map.end_data;
2271 mm->start_brk = prctl_map.start_brk;
2272 mm->brk = prctl_map.brk;
2273 mm->start_stack = prctl_map.start_stack;
2274 mm->arg_start = prctl_map.arg_start;
2275 mm->arg_end = prctl_map.arg_end;
2276 mm->env_start = prctl_map.env_start;
2277 mm->env_end = prctl_map.env_end;
2278
028ee4be 2279 error = 0;
028ee4be 2280out:
bc81426f 2281 spin_unlock(&mm->arg_lock);
d8ed45c5 2282 mmap_read_unlock(mm);
028ee4be
CG
2283 return error;
2284}
300f786b 2285
52b36941 2286#ifdef CONFIG_CHECKPOINT_RESTORE
986b9eac 2287static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr)
300f786b
CG
2288{
2289 return put_user(me->clear_child_tid, tid_addr);
2290}
52b36941 2291#else
986b9eac 2292static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr)
300f786b
CG
2293{
2294 return -EINVAL;
2295}
028ee4be
CG
2296#endif
2297
749860ce
PT
2298static int propagate_has_child_subreaper(struct task_struct *p, void *data)
2299{
2300 /*
5afe69c2
XC
2301 * If task has has_child_subreaper - all its descendants
2302 * already have these flag too and new descendants will
749860ce
PT
2303 * inherit it on fork, skip them.
2304 *
2305 * If we've found child_reaper - skip descendants in
2306 * it's subtree as they will never get out pidns.
2307 */
2308 if (p->signal->has_child_subreaper ||
2309 is_child_reaper(task_pid(p)))
2310 return 0;
2311
2312 p->signal->has_child_subreaper = 1;
2313 return 1;
2314}
2315
7bbf1373 2316int __weak arch_prctl_spec_ctrl_get(struct task_struct *t, unsigned long which)
b617cfc8
TG
2317{
2318 return -EINVAL;
2319}
2320
7bbf1373
KC
2321int __weak arch_prctl_spec_ctrl_set(struct task_struct *t, unsigned long which,
2322 unsigned long ctrl)
b617cfc8
TG
2323{
2324 return -EINVAL;
2325}
2326
a37b0715 2327#define PR_IO_FLUSHER (PF_MEMALLOC_NOIO | PF_LOCAL_THROTTLE)
8d19f1c8 2328
9a10064f
CC
2329#ifdef CONFIG_ANON_VMA_NAME
2330
2331#define ANON_VMA_NAME_MAX_LEN 80
2332#define ANON_VMA_NAME_INVALID_CHARS "\\`$[]"
2333
2334static inline bool is_valid_name_char(char ch)
2335{
2336 /* printable ascii characters, excluding ANON_VMA_NAME_INVALID_CHARS */
2337 return ch > 0x1f && ch < 0x7f &&
2338 !strchr(ANON_VMA_NAME_INVALID_CHARS, ch);
2339}
2340
2341static int prctl_set_vma(unsigned long opt, unsigned long addr,
2342 unsigned long size, unsigned long arg)
2343{
2344 struct mm_struct *mm = current->mm;
2345 const char __user *uname;
5c26f6ac 2346 struct anon_vma_name *anon_name = NULL;
9a10064f
CC
2347 int error;
2348
2349 switch (opt) {
2350 case PR_SET_VMA_ANON_NAME:
2351 uname = (const char __user *)arg;
2352 if (uname) {
5c26f6ac 2353 char *name, *pch;
9a10064f 2354
5c26f6ac 2355 name = strndup_user(uname, ANON_VMA_NAME_MAX_LEN);
9a10064f
CC
2356 if (IS_ERR(name))
2357 return PTR_ERR(name);
2358
2359 for (pch = name; *pch != '\0'; pch++) {
2360 if (!is_valid_name_char(*pch)) {
2361 kfree(name);
2362 return -EINVAL;
2363 }
2364 }
5c26f6ac
SB
2365 /* anon_vma has its own copy */
2366 anon_name = anon_vma_name_alloc(name);
2367 kfree(name);
2368 if (!anon_name)
2369 return -ENOMEM;
2370
9a10064f
CC
2371 }
2372
2373 mmap_write_lock(mm);
5c26f6ac 2374 error = madvise_set_anon_name(mm, addr, size, anon_name);
9a10064f 2375 mmap_write_unlock(mm);
5c26f6ac 2376 anon_vma_name_put(anon_name);
9a10064f
CC
2377 break;
2378 default:
2379 error = -EINVAL;
2380 }
2381
2382 return error;
2383}
2384
2385#else /* CONFIG_ANON_VMA_NAME */
2386static int prctl_set_vma(unsigned long opt, unsigned long start,
2387 unsigned long size, unsigned long arg)
2388{
2389 return -EINVAL;
2390}
2391#endif /* CONFIG_ANON_VMA_NAME */
2392
24e41bf8
FR
2393static inline unsigned long get_current_mdwe(void)
2394{
2395 unsigned long ret = 0;
2396
2397 if (test_bit(MMF_HAS_MDWE, &current->mm->flags))
2398 ret |= PR_MDWE_REFUSE_EXEC_GAIN;
2399 if (test_bit(MMF_HAS_MDWE_NO_INHERIT, &current->mm->flags))
2400 ret |= PR_MDWE_NO_INHERIT;
2401
2402 return ret;
2403}
2404
b507808e
JG
2405static inline int prctl_set_mdwe(unsigned long bits, unsigned long arg3,
2406 unsigned long arg4, unsigned long arg5)
2407{
24e41bf8
FR
2408 unsigned long current_bits;
2409
b507808e
JG
2410 if (arg3 || arg4 || arg5)
2411 return -EINVAL;
2412
24e41bf8
FR
2413 if (bits & ~(PR_MDWE_REFUSE_EXEC_GAIN | PR_MDWE_NO_INHERIT))
2414 return -EINVAL;
2415
2416 /* NO_INHERIT only makes sense with REFUSE_EXEC_GAIN */
2417 if (bits & PR_MDWE_NO_INHERIT && !(bits & PR_MDWE_REFUSE_EXEC_GAIN))
b507808e
JG
2418 return -EINVAL;
2419
d5aad4c2
ZW
2420 /*
2421 * EOPNOTSUPP might be more appropriate here in principle, but
2422 * existing userspace depends on EINVAL specifically.
2423 */
2424 if (!arch_memory_deny_write_exec_supported())
79383813
HD
2425 return -EINVAL;
2426
24e41bf8
FR
2427 current_bits = get_current_mdwe();
2428 if (current_bits && current_bits != bits)
2429 return -EPERM; /* Cannot unset the flags */
2430
2431 if (bits & PR_MDWE_NO_INHERIT)
2432 set_bit(MMF_HAS_MDWE_NO_INHERIT, &current->mm->flags);
b507808e
JG
2433 if (bits & PR_MDWE_REFUSE_EXEC_GAIN)
2434 set_bit(MMF_HAS_MDWE, &current->mm->flags);
b507808e
JG
2435
2436 return 0;
2437}
2438
2439static inline int prctl_get_mdwe(unsigned long arg2, unsigned long arg3,
2440 unsigned long arg4, unsigned long arg5)
2441{
2442 if (arg2 || arg3 || arg4 || arg5)
2443 return -EINVAL;
24e41bf8 2444 return get_current_mdwe();
b507808e
JG
2445}
2446
ddc65971
JT
2447static int prctl_get_auxv(void __user *addr, unsigned long len)
2448{
2449 struct mm_struct *mm = current->mm;
2450 unsigned long size = min_t(unsigned long, sizeof(mm->saved_auxv), len);
2451
2452 if (size && copy_to_user(addr, mm->saved_auxv, size))
2453 return -EFAULT;
2454 return sizeof(mm->saved_auxv);
2455}
2456
c4ea37c2
HC
2457SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
2458 unsigned long, arg4, unsigned long, arg5)
1da177e4 2459{
b6dff3ec
DH
2460 struct task_struct *me = current;
2461 unsigned char comm[sizeof(me->comm)];
2462 long error;
1da177e4 2463
d84f4f99
DH
2464 error = security_task_prctl(option, arg2, arg3, arg4, arg5);
2465 if (error != -ENOSYS)
1da177e4
LT
2466 return error;
2467
d84f4f99 2468 error = 0;
1da177e4 2469 switch (option) {
f3cbd435
AM
2470 case PR_SET_PDEATHSIG:
2471 if (!valid_signal(arg2)) {
2472 error = -EINVAL;
1da177e4 2473 break;
f3cbd435
AM
2474 }
2475 me->pdeath_signal = arg2;
2476 break;
2477 case PR_GET_PDEATHSIG:
2478 error = put_user(me->pdeath_signal, (int __user *)arg2);
2479 break;
2480 case PR_GET_DUMPABLE:
2481 error = get_dumpable(me->mm);
2482 break;
2483 case PR_SET_DUMPABLE:
2484 if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) {
2485 error = -EINVAL;
1da177e4 2486 break;
f3cbd435
AM
2487 }
2488 set_dumpable(me->mm, arg2);
2489 break;
1da177e4 2490
f3cbd435
AM
2491 case PR_SET_UNALIGN:
2492 error = SET_UNALIGN_CTL(me, arg2);
2493 break;
2494 case PR_GET_UNALIGN:
2495 error = GET_UNALIGN_CTL(me, arg2);
2496 break;
2497 case PR_SET_FPEMU:
2498 error = SET_FPEMU_CTL(me, arg2);
2499 break;
2500 case PR_GET_FPEMU:
2501 error = GET_FPEMU_CTL(me, arg2);
2502 break;
2503 case PR_SET_FPEXC:
2504 error = SET_FPEXC_CTL(me, arg2);
2505 break;
2506 case PR_GET_FPEXC:
2507 error = GET_FPEXC_CTL(me, arg2);
2508 break;
2509 case PR_GET_TIMING:
2510 error = PR_TIMING_STATISTICAL;
2511 break;
2512 case PR_SET_TIMING:
2513 if (arg2 != PR_TIMING_STATISTICAL)
2514 error = -EINVAL;
2515 break;
2516 case PR_SET_NAME:
2517 comm[sizeof(me->comm) - 1] = 0;
2518 if (strncpy_from_user(comm, (char __user *)arg2,
2519 sizeof(me->comm) - 1) < 0)
2520 return -EFAULT;
2521 set_task_comm(me, comm);
2522 proc_comm_connector(me);
2523 break;
2524 case PR_GET_NAME:
2525 get_task_comm(comm, me);
2526 if (copy_to_user((char __user *)arg2, comm, sizeof(comm)))
2527 return -EFAULT;
2528 break;
2529 case PR_GET_ENDIAN:
2530 error = GET_ENDIAN(me, arg2);
2531 break;
2532 case PR_SET_ENDIAN:
2533 error = SET_ENDIAN(me, arg2);
2534 break;
2535 case PR_GET_SECCOMP:
2536 error = prctl_get_seccomp();
2537 break;
2538 case PR_SET_SECCOMP:
2539 error = prctl_set_seccomp(arg2, (char __user *)arg3);
2540 break;
2541 case PR_GET_TSC:
2542 error = GET_TSC_CTL(arg2);
2543 break;
2544 case PR_SET_TSC:
2545 error = SET_TSC_CTL(arg2);
2546 break;
2547 case PR_TASK_PERF_EVENTS_DISABLE:
2548 error = perf_event_task_disable();
2549 break;
2550 case PR_TASK_PERF_EVENTS_ENABLE:
2551 error = perf_event_task_enable();
2552 break;
2553 case PR_GET_TIMERSLACK:
da8b44d5
JS
2554 if (current->timer_slack_ns > ULONG_MAX)
2555 error = ULONG_MAX;
2556 else
2557 error = current->timer_slack_ns;
f3cbd435
AM
2558 break;
2559 case PR_SET_TIMERSLACK:
2004cef1 2560 if (rt_or_dl_task_policy(current))
ed4fb6d7 2561 break;
f3cbd435
AM
2562 if (arg2 <= 0)
2563 current->timer_slack_ns =
6976675d 2564 current->default_timer_slack_ns;
f3cbd435
AM
2565 else
2566 current->timer_slack_ns = arg2;
2567 break;
2568 case PR_MCE_KILL:
2569 if (arg4 | arg5)
2570 return -EINVAL;
2571 switch (arg2) {
2572 case PR_MCE_KILL_CLEAR:
2573 if (arg3 != 0)
4db96cf0 2574 return -EINVAL;
f3cbd435 2575 current->flags &= ~PF_MCE_PROCESS;
4db96cf0 2576 break;
f3cbd435
AM
2577 case PR_MCE_KILL_SET:
2578 current->flags |= PF_MCE_PROCESS;
2579 if (arg3 == PR_MCE_KILL_EARLY)
2580 current->flags |= PF_MCE_EARLY;
2581 else if (arg3 == PR_MCE_KILL_LATE)
2582 current->flags &= ~PF_MCE_EARLY;
2583 else if (arg3 == PR_MCE_KILL_DEFAULT)
2584 current->flags &=
2585 ~(PF_MCE_EARLY|PF_MCE_PROCESS);
1087e9b4 2586 else
259e5e6c 2587 return -EINVAL;
259e5e6c 2588 break;
1da177e4 2589 default:
f3cbd435
AM
2590 return -EINVAL;
2591 }
2592 break;
2593 case PR_MCE_KILL_GET:
2594 if (arg2 | arg3 | arg4 | arg5)
2595 return -EINVAL;
2596 if (current->flags & PF_MCE_PROCESS)
2597 error = (current->flags & PF_MCE_EARLY) ?
2598 PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE;
2599 else
2600 error = PR_MCE_KILL_DEFAULT;
2601 break;
2602 case PR_SET_MM:
2603 error = prctl_set_mm(arg2, arg3, arg4, arg5);
2604 break;
2605 case PR_GET_TID_ADDRESS:
986b9eac 2606 error = prctl_get_tid_address(me, (int __user * __user *)arg2);
f3cbd435
AM
2607 break;
2608 case PR_SET_CHILD_SUBREAPER:
2609 me->signal->is_child_subreaper = !!arg2;
749860ce
PT
2610 if (!arg2)
2611 break;
2612
2613 walk_process_tree(me, propagate_has_child_subreaper, NULL);
f3cbd435
AM
2614 break;
2615 case PR_GET_CHILD_SUBREAPER:
2616 error = put_user(me->signal->is_child_subreaper,
2617 (int __user *)arg2);
2618 break;
2619 case PR_SET_NO_NEW_PRIVS:
2620 if (arg2 != 1 || arg3 || arg4 || arg5)
2621 return -EINVAL;
2622
1d4457f9 2623 task_set_no_new_privs(current);
f3cbd435
AM
2624 break;
2625 case PR_GET_NO_NEW_PRIVS:
2626 if (arg2 || arg3 || arg4 || arg5)
2627 return -EINVAL;
1d4457f9 2628 return task_no_new_privs(current) ? 1 : 0;
a0715cc2
AT
2629 case PR_GET_THP_DISABLE:
2630 if (arg2 || arg3 || arg4 || arg5)
2631 return -EINVAL;
18600332 2632 error = !!test_bit(MMF_DISABLE_THP, &me->mm->flags);
a0715cc2
AT
2633 break;
2634 case PR_SET_THP_DISABLE:
2635 if (arg3 || arg4 || arg5)
2636 return -EINVAL;
d8ed45c5 2637 if (mmap_write_lock_killable(me->mm))
17b0573d 2638 return -EINTR;
a0715cc2 2639 if (arg2)
18600332 2640 set_bit(MMF_DISABLE_THP, &me->mm->flags);
a0715cc2 2641 else
18600332 2642 clear_bit(MMF_DISABLE_THP, &me->mm->flags);
d8ed45c5 2643 mmap_write_unlock(me->mm);
a0715cc2 2644 break;
fe3d197f 2645 case PR_MPX_ENABLE_MANAGEMENT:
fe3d197f 2646 case PR_MPX_DISABLE_MANAGEMENT:
f240652b
DH
2647 /* No longer implemented: */
2648 return -EINVAL;
9791554b
PB
2649 case PR_SET_FP_MODE:
2650 error = SET_FP_MODE(me, arg2);
2651 break;
2652 case PR_GET_FP_MODE:
2653 error = GET_FP_MODE(me);
2654 break;
2d2123bc
DM
2655 case PR_SVE_SET_VL:
2656 error = SVE_SET_VL(arg2);
2657 break;
2658 case PR_SVE_GET_VL:
2659 error = SVE_GET_VL();
2660 break;
9e4ab6c8
MB
2661 case PR_SME_SET_VL:
2662 error = SME_SET_VL(arg2);
2663 break;
2664 case PR_SME_GET_VL:
2665 error = SME_GET_VL();
2666 break;
b617cfc8
TG
2667 case PR_GET_SPECULATION_CTRL:
2668 if (arg3 || arg4 || arg5)
2669 return -EINVAL;
7bbf1373 2670 error = arch_prctl_spec_ctrl_get(me, arg2);
b617cfc8
TG
2671 break;
2672 case PR_SET_SPECULATION_CTRL:
2673 if (arg4 || arg5)
2674 return -EINVAL;
7bbf1373 2675 error = arch_prctl_spec_ctrl_set(me, arg2, arg3);
b617cfc8 2676 break;
ba830885
KM
2677 case PR_PAC_RESET_KEYS:
2678 if (arg3 || arg4 || arg5)
2679 return -EINVAL;
2680 error = PAC_RESET_KEYS(me, arg2);
2681 break;
20169862
PC
2682 case PR_PAC_SET_ENABLED_KEYS:
2683 if (arg4 || arg5)
2684 return -EINVAL;
2685 error = PAC_SET_ENABLED_KEYS(me, arg2, arg3);
2686 break;
2687 case PR_PAC_GET_ENABLED_KEYS:
2688 if (arg2 || arg3 || arg4 || arg5)
2689 return -EINVAL;
2690 error = PAC_GET_ENABLED_KEYS(me);
2691 break;
63f0c603 2692 case PR_SET_TAGGED_ADDR_CTRL:
3e91ec89
CM
2693 if (arg3 || arg4 || arg5)
2694 return -EINVAL;
63f0c603
CM
2695 error = SET_TAGGED_ADDR_CTRL(arg2);
2696 break;
2697 case PR_GET_TAGGED_ADDR_CTRL:
3e91ec89
CM
2698 if (arg2 || arg3 || arg4 || arg5)
2699 return -EINVAL;
63f0c603
CM
2700 error = GET_TAGGED_ADDR_CTRL();
2701 break;
8d19f1c8
MC
2702 case PR_SET_IO_FLUSHER:
2703 if (!capable(CAP_SYS_RESOURCE))
2704 return -EPERM;
2705
2706 if (arg3 || arg4 || arg5)
2707 return -EINVAL;
2708
2709 if (arg2 == 1)
2710 current->flags |= PR_IO_FLUSHER;
2711 else if (!arg2)
2712 current->flags &= ~PR_IO_FLUSHER;
2713 else
2714 return -EINVAL;
2715 break;
2716 case PR_GET_IO_FLUSHER:
2717 if (!capable(CAP_SYS_RESOURCE))
2718 return -EPERM;
2719
2720 if (arg2 || arg3 || arg4 || arg5)
2721 return -EINVAL;
2722
2723 error = (current->flags & PR_IO_FLUSHER) == PR_IO_FLUSHER;
2724 break;
1446e1df
GKB
2725 case PR_SET_SYSCALL_USER_DISPATCH:
2726 error = set_syscall_user_dispatch(arg2, arg3, arg4,
2727 (char __user *) arg5);
2728 break;
7ac592aa
CH
2729#ifdef CONFIG_SCHED_CORE
2730 case PR_SCHED_CORE:
2731 error = sched_core_share_pid(arg2, arg3, arg4, arg5);
2732 break;
2733#endif
b507808e
JG
2734 case PR_SET_MDWE:
2735 error = prctl_set_mdwe(arg2, arg3, arg4, arg5);
2736 break;
2737 case PR_GET_MDWE:
2738 error = prctl_get_mdwe(arg2, arg3, arg4, arg5);
2739 break;
628d701f
BG
2740 case PR_PPC_GET_DEXCR:
2741 if (arg3 || arg4 || arg5)
2742 return -EINVAL;
2743 error = PPC_GET_DEXCR_ASPECT(me, arg2);
2744 break;
2745 case PR_PPC_SET_DEXCR:
2746 if (arg4 || arg5)
2747 return -EINVAL;
2748 error = PPC_SET_DEXCR_ASPECT(me, arg2, arg3);
2749 break;
9a10064f
CC
2750 case PR_SET_VMA:
2751 error = prctl_set_vma(arg2, arg3, arg4, arg5);
2752 break;
636e3483
MO
2753 case PR_GET_AUXV:
2754 if (arg4 || arg5)
2755 return -EINVAL;
2756 error = prctl_get_auxv((void __user *)arg2, arg3);
2757 break;
d7597f59
SR
2758#ifdef CONFIG_KSM
2759 case PR_SET_MEMORY_MERGE:
2760 if (arg3 || arg4 || arg5)
2761 return -EINVAL;
2762 if (mmap_write_lock_killable(me->mm))
2763 return -EINTR;
2764
24139c07 2765 if (arg2)
d7597f59 2766 error = ksm_enable_merge_any(me->mm);
24139c07
DH
2767 else
2768 error = ksm_disable_merge_any(me->mm);
d7597f59
SR
2769 mmap_write_unlock(me->mm);
2770 break;
2771 case PR_GET_MEMORY_MERGE:
2772 if (arg2 || arg3 || arg4 || arg5)
2773 return -EINVAL;
2774
2775 error = !!test_bit(MMF_VM_MERGE_ANY, &me->mm->flags);
2776 break;
2777#endif
1fd96a3e
AC
2778 case PR_RISCV_V_SET_CONTROL:
2779 error = RISCV_V_SET_CONTROL(arg2);
2780 break;
2781 case PR_RISCV_V_GET_CONTROL:
2782 error = RISCV_V_GET_CONTROL();
2783 break;
6b9391b5
CJ
2784 case PR_RISCV_SET_ICACHE_FLUSH_CTX:
2785 error = RISCV_SET_ICACHE_FLUSH_CTX(arg2, arg3);
2786 break;
f3cbd435
AM
2787 default:
2788 error = -EINVAL;
2789 break;
1da177e4
LT
2790 }
2791 return error;
2792}
3cfc348b 2793
836f92ad
HC
2794SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
2795 struct getcpu_cache __user *, unused)
3cfc348b
AK
2796{
2797 int err = 0;
2798 int cpu = raw_smp_processor_id();
ec94fc3d 2799
3cfc348b
AK
2800 if (cpup)
2801 err |= put_user(cpu, cpup);
2802 if (nodep)
2803 err |= put_user(cpu_to_node(cpu), nodep);
3cfc348b
AK
2804 return err ? -EFAULT : 0;
2805}
10a0a8d4 2806
4a22f166
SR
2807/**
2808 * do_sysinfo - fill in sysinfo struct
2809 * @info: pointer to buffer to fill
2810 */
2811static int do_sysinfo(struct sysinfo *info)
2812{
2813 unsigned long mem_total, sav_total;
2814 unsigned int mem_unit, bitcount;
dc1b7b6c 2815 struct timespec64 tp;
4a22f166
SR
2816
2817 memset(info, 0, sizeof(struct sysinfo));
2818
dc1b7b6c 2819 ktime_get_boottime_ts64(&tp);
ecc421e0 2820 timens_add_boottime(&tp);
4a22f166
SR
2821 info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0);
2822
2823 get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT);
2824
2825 info->procs = nr_threads;
2826
2827 si_meminfo(info);
2828 si_swapinfo(info);
2829
2830 /*
2831 * If the sum of all the available memory (i.e. ram + swap)
2832 * is less than can be stored in a 32 bit unsigned long then
2833 * we can be binary compatible with 2.2.x kernels. If not,
2834 * well, in that case 2.2.x was broken anyways...
2835 *
2836 * -Erik Andersen <andersee@debian.org>
2837 */
2838
2839 mem_total = info->totalram + info->totalswap;
2840 if (mem_total < info->totalram || mem_total < info->totalswap)
2841 goto out;
2842 bitcount = 0;
2843 mem_unit = info->mem_unit;
2844 while (mem_unit > 1) {
2845 bitcount++;
2846 mem_unit >>= 1;
2847 sav_total = mem_total;
2848 mem_total <<= 1;
2849 if (mem_total < sav_total)
2850 goto out;
2851 }
2852
2853 /*
2854 * If mem_total did not overflow, multiply all memory values by
2855 * info->mem_unit and set it to 1. This leaves things compatible
2856 * with 2.2.x, and also retains compatibility with earlier 2.4.x
2857 * kernels...
2858 */
2859
2860 info->mem_unit = 1;
2861 info->totalram <<= bitcount;
2862 info->freeram <<= bitcount;
2863 info->sharedram <<= bitcount;
2864 info->bufferram <<= bitcount;
2865 info->totalswap <<= bitcount;
2866 info->freeswap <<= bitcount;
2867 info->totalhigh <<= bitcount;
2868 info->freehigh <<= bitcount;
2869
2870out:
2871 return 0;
2872}
2873
2874SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info)
2875{
2876 struct sysinfo val;
2877
2878 do_sysinfo(&val);
2879
2880 if (copy_to_user(info, &val, sizeof(struct sysinfo)))
2881 return -EFAULT;
2882
2883 return 0;
2884}
2885
2886#ifdef CONFIG_COMPAT
2887struct compat_sysinfo {
2888 s32 uptime;
2889 u32 loads[3];
2890 u32 totalram;
2891 u32 freeram;
2892 u32 sharedram;
2893 u32 bufferram;
2894 u32 totalswap;
2895 u32 freeswap;
2896 u16 procs;
2897 u16 pad;
2898 u32 totalhigh;
2899 u32 freehigh;
2900 u32 mem_unit;
2901 char _f[20-2*sizeof(u32)-sizeof(int)];
2902};
2903
2904COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
2905{
2906 struct sysinfo s;
ce5155c4 2907 struct compat_sysinfo s_32;
4a22f166
SR
2908
2909 do_sysinfo(&s);
2910
2911 /* Check to see if any memory value is too large for 32-bit and scale
2912 * down if needed
2913 */
0baae41e 2914 if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) {
4a22f166
SR
2915 int bitcount = 0;
2916
2917 while (s.mem_unit < PAGE_SIZE) {
2918 s.mem_unit <<= 1;
2919 bitcount++;
2920 }
2921
2922 s.totalram >>= bitcount;
2923 s.freeram >>= bitcount;
2924 s.sharedram >>= bitcount;
2925 s.bufferram >>= bitcount;
2926 s.totalswap >>= bitcount;
2927 s.freeswap >>= bitcount;
2928 s.totalhigh >>= bitcount;
2929 s.freehigh >>= bitcount;
2930 }
2931
ce5155c4
AV
2932 memset(&s_32, 0, sizeof(s_32));
2933 s_32.uptime = s.uptime;
2934 s_32.loads[0] = s.loads[0];
2935 s_32.loads[1] = s.loads[1];
2936 s_32.loads[2] = s.loads[2];
2937 s_32.totalram = s.totalram;
2938 s_32.freeram = s.freeram;
2939 s_32.sharedram = s.sharedram;
2940 s_32.bufferram = s.bufferram;
2941 s_32.totalswap = s.totalswap;
2942 s_32.freeswap = s.freeswap;
2943 s_32.procs = s.procs;
2944 s_32.totalhigh = s.totalhigh;
2945 s_32.freehigh = s.freehigh;
2946 s_32.mem_unit = s.mem_unit;
2947 if (copy_to_user(info, &s_32, sizeof(s_32)))
4a22f166 2948 return -EFAULT;
4a22f166
SR
2949 return 0;
2950}
2951#endif /* CONFIG_COMPAT */