Line data Source code
1 : // SPDX-License-Identifier: GPL-2.0
2 : /*
3 : * linux/kernel/sys.c
4 : *
5 : * Copyright (C) 1991, 1992 Linus Torvalds
6 : */
7 :
8 : #include <linux/export.h>
9 : #include <linux/mm.h>
10 : #include <linux/mm_inline.h>
11 : #include <linux/utsname.h>
12 : #include <linux/mman.h>
13 : #include <linux/reboot.h>
14 : #include <linux/prctl.h>
15 : #include <linux/highuid.h>
16 : #include <linux/fs.h>
17 : #include <linux/kmod.h>
18 : #include <linux/ksm.h>
19 : #include <linux/perf_event.h>
20 : #include <linux/resource.h>
21 : #include <linux/kernel.h>
22 : #include <linux/workqueue.h>
23 : #include <linux/capability.h>
24 : #include <linux/device.h>
25 : #include <linux/key.h>
26 : #include <linux/times.h>
27 : #include <linux/posix-timers.h>
28 : #include <linux/security.h>
29 : #include <linux/random.h>
30 : #include <linux/suspend.h>
31 : #include <linux/tty.h>
32 : #include <linux/signal.h>
33 : #include <linux/cn_proc.h>
34 : #include <linux/getcpu.h>
35 : #include <linux/task_io_accounting_ops.h>
36 : #include <linux/seccomp.h>
37 : #include <linux/cpu.h>
38 : #include <linux/personality.h>
39 : #include <linux/ptrace.h>
40 : #include <linux/fs_struct.h>
41 : #include <linux/file.h>
42 : #include <linux/mount.h>
43 : #include <linux/gfp.h>
44 : #include <linux/syscore_ops.h>
45 : #include <linux/version.h>
46 : #include <linux/ctype.h>
47 : #include <linux/syscall_user_dispatch.h>
48 :
49 : #include <linux/compat.h>
50 : #include <linux/syscalls.h>
51 : #include <linux/kprobes.h>
52 : #include <linux/user_namespace.h>
53 : #include <linux/time_namespace.h>
54 : #include <linux/binfmts.h>
55 :
56 : #include <linux/sched.h>
57 : #include <linux/sched/autogroup.h>
58 : #include <linux/sched/loadavg.h>
59 : #include <linux/sched/stat.h>
60 : #include <linux/sched/mm.h>
61 : #include <linux/sched/coredump.h>
62 : #include <linux/sched/task.h>
63 : #include <linux/sched/cputime.h>
64 : #include <linux/rcupdate.h>
65 : #include <linux/uidgid.h>
66 : #include <linux/cred.h>
67 :
68 : #include <linux/nospec.h>
69 :
70 : #include <linux/kmsg_dump.h>
71 : /* Move somewhere else to avoid recompiling? */
72 : #include <generated/utsrelease.h>
73 :
74 : #include <linux/uaccess.h>
75 : #include <asm/io.h>
76 : #include <asm/unistd.h>
77 :
78 : #include "uid16.h"
79 :
80 : #ifndef SET_UNALIGN_CTL
81 : # define SET_UNALIGN_CTL(a, b) (-EINVAL)
82 : #endif
83 : #ifndef GET_UNALIGN_CTL
84 : # define GET_UNALIGN_CTL(a, b) (-EINVAL)
85 : #endif
86 : #ifndef SET_FPEMU_CTL
87 : # define SET_FPEMU_CTL(a, b) (-EINVAL)
88 : #endif
89 : #ifndef GET_FPEMU_CTL
90 : # define GET_FPEMU_CTL(a, b) (-EINVAL)
91 : #endif
92 : #ifndef SET_FPEXC_CTL
93 : # define SET_FPEXC_CTL(a, b) (-EINVAL)
94 : #endif
95 : #ifndef GET_FPEXC_CTL
96 : # define GET_FPEXC_CTL(a, b) (-EINVAL)
97 : #endif
98 : #ifndef GET_ENDIAN
99 : # define GET_ENDIAN(a, b) (-EINVAL)
100 : #endif
101 : #ifndef SET_ENDIAN
102 : # define SET_ENDIAN(a, b) (-EINVAL)
103 : #endif
104 : #ifndef GET_TSC_CTL
105 : # define GET_TSC_CTL(a) (-EINVAL)
106 : #endif
107 : #ifndef SET_TSC_CTL
108 : # define SET_TSC_CTL(a) (-EINVAL)
109 : #endif
110 : #ifndef GET_FP_MODE
111 : # define GET_FP_MODE(a) (-EINVAL)
112 : #endif
113 : #ifndef SET_FP_MODE
114 : # define SET_FP_MODE(a,b) (-EINVAL)
115 : #endif
116 : #ifndef SVE_SET_VL
117 : # define SVE_SET_VL(a) (-EINVAL)
118 : #endif
119 : #ifndef SVE_GET_VL
120 : # define SVE_GET_VL() (-EINVAL)
121 : #endif
122 : #ifndef SME_SET_VL
123 : # define SME_SET_VL(a) (-EINVAL)
124 : #endif
125 : #ifndef SME_GET_VL
126 : # define SME_GET_VL() (-EINVAL)
127 : #endif
128 : #ifndef PAC_RESET_KEYS
129 : # define PAC_RESET_KEYS(a, b) (-EINVAL)
130 : #endif
131 : #ifndef PAC_SET_ENABLED_KEYS
132 : # define PAC_SET_ENABLED_KEYS(a, b, c) (-EINVAL)
133 : #endif
134 : #ifndef PAC_GET_ENABLED_KEYS
135 : # define PAC_GET_ENABLED_KEYS(a) (-EINVAL)
136 : #endif
137 : #ifndef SET_TAGGED_ADDR_CTRL
138 : # define SET_TAGGED_ADDR_CTRL(a) (-EINVAL)
139 : #endif
140 : #ifndef GET_TAGGED_ADDR_CTRL
141 : # define GET_TAGGED_ADDR_CTRL() (-EINVAL)
142 : #endif
143 : #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
149 :
150 : /*
151 : * this is where the system-wide overflow UID and GID are defined, for
152 : * architectures that now have 32-bit UID/GID but didn't in the past
153 : */
154 :
155 : int overflowuid = DEFAULT_OVERFLOWUID;
156 : int overflowgid = DEFAULT_OVERFLOWGID;
157 :
158 : EXPORT_SYMBOL(overflowuid);
159 : EXPORT_SYMBOL(overflowgid);
160 :
161 : /*
162 : * the same as above, but for filesystems which can only store a 16-bit
163 : * UID and GID. as such, this is needed on all architectures
164 : */
165 :
166 : int fs_overflowuid = DEFAULT_FS_OVERFLOWUID;
167 : int fs_overflowgid = DEFAULT_FS_OVERFLOWGID;
168 :
169 : EXPORT_SYMBOL(fs_overflowuid);
170 : EXPORT_SYMBOL(fs_overflowgid);
171 :
172 : /*
173 : * Returns true if current's euid is same as p's uid or euid,
174 : * or has CAP_SYS_NICE to p's user_ns.
175 : *
176 : * Called with rcu_read_lock, creds are safe
177 : */
178 0 : static bool set_one_prio_perm(struct task_struct *p)
179 : {
180 0 : const struct cred *cred = current_cred(), *pcred = __task_cred(p);
181 :
182 0 : if (uid_eq(pcred->uid, cred->euid) ||
183 0 : uid_eq(pcred->euid, cred->euid))
184 : return true;
185 0 : if (ns_capable(pcred->user_ns, CAP_SYS_NICE))
186 : return true;
187 0 : return false;
188 : }
189 :
190 : /*
191 : * set the priority of a task
192 : * - the caller must hold the RCU read lock
193 : */
194 0 : static int set_one_prio(struct task_struct *p, int niceval, int error)
195 : {
196 : int no_nice;
197 :
198 0 : if (!set_one_prio_perm(p)) {
199 : error = -EPERM;
200 : goto out;
201 : }
202 0 : if (niceval < task_nice(p) && !can_nice(p, niceval)) {
203 : error = -EACCES;
204 : goto out;
205 : }
206 0 : no_nice = security_task_setnice(p, niceval);
207 0 : if (no_nice) {
208 : error = no_nice;
209 : goto out;
210 : }
211 0 : if (error == -ESRCH)
212 0 : error = 0;
213 0 : set_user_nice(p, niceval);
214 : out:
215 0 : return error;
216 : }
217 :
218 0 : SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
219 : {
220 : struct task_struct *g, *p;
221 : struct user_struct *user;
222 0 : const struct cred *cred = current_cred();
223 0 : int error = -EINVAL;
224 : struct pid *pgrp;
225 : kuid_t uid;
226 :
227 0 : if (which > PRIO_USER || which < PRIO_PROCESS)
228 : goto out;
229 :
230 : /* normalize: avoid signed division (rounding problems) */
231 0 : error = -ESRCH;
232 0 : if (niceval < MIN_NICE)
233 0 : niceval = MIN_NICE;
234 0 : if (niceval > MAX_NICE)
235 0 : niceval = MAX_NICE;
236 :
237 : rcu_read_lock();
238 0 : switch (which) {
239 : case PRIO_PROCESS:
240 0 : if (who)
241 0 : p = find_task_by_vpid(who);
242 : else
243 0 : p = current;
244 0 : if (p)
245 0 : error = set_one_prio(p, niceval, error);
246 : break;
247 : case PRIO_PGRP:
248 0 : if (who)
249 0 : pgrp = find_vpid(who);
250 : else
251 0 : pgrp = task_pgrp(current);
252 0 : read_lock(&tasklist_lock);
253 0 : do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
254 0 : error = set_one_prio(p, niceval, error);
255 0 : } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
256 0 : read_unlock(&tasklist_lock);
257 0 : break;
258 : case PRIO_USER:
259 0 : uid = make_kuid(cred->user_ns, who);
260 0 : user = cred->user;
261 0 : if (!who)
262 0 : uid = cred->uid;
263 0 : else if (!uid_eq(uid, cred->uid)) {
264 0 : user = find_user(uid);
265 0 : if (!user)
266 : goto out_unlock; /* No processes for this user */
267 : }
268 0 : for_each_process_thread(g, p) {
269 0 : if (uid_eq(task_uid(p), uid) && task_pid_vnr(p))
270 0 : error = set_one_prio(p, niceval, error);
271 : }
272 0 : if (!uid_eq(uid, cred->uid))
273 0 : free_uid(user); /* For find_user() */
274 : break;
275 : }
276 : out_unlock:
277 : rcu_read_unlock();
278 : out:
279 0 : return error;
280 : }
281 :
282 : /*
283 : * Ugh. To avoid negative return values, "getpriority()" will
284 : * not return the normal nice-value, but a negated value that
285 : * has been offset by 20 (ie it returns 40..1 instead of -20..19)
286 : * to stay compatible.
287 : */
288 0 : SYSCALL_DEFINE2(getpriority, int, which, int, who)
289 : {
290 : struct task_struct *g, *p;
291 : struct user_struct *user;
292 0 : const struct cred *cred = current_cred();
293 0 : long niceval, retval = -ESRCH;
294 : struct pid *pgrp;
295 : kuid_t uid;
296 :
297 0 : if (which > PRIO_USER || which < PRIO_PROCESS)
298 : return -EINVAL;
299 :
300 : rcu_read_lock();
301 0 : switch (which) {
302 : case PRIO_PROCESS:
303 0 : if (who)
304 0 : p = find_task_by_vpid(who);
305 : else
306 0 : p = current;
307 0 : if (p) {
308 0 : niceval = nice_to_rlimit(task_nice(p));
309 0 : if (niceval > retval)
310 0 : retval = niceval;
311 : }
312 : break;
313 : case PRIO_PGRP:
314 0 : if (who)
315 0 : pgrp = find_vpid(who);
316 : else
317 0 : pgrp = task_pgrp(current);
318 0 : read_lock(&tasklist_lock);
319 0 : do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
320 0 : niceval = nice_to_rlimit(task_nice(p));
321 0 : if (niceval > retval)
322 0 : retval = niceval;
323 0 : } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
324 0 : read_unlock(&tasklist_lock);
325 0 : break;
326 : case PRIO_USER:
327 0 : uid = make_kuid(cred->user_ns, who);
328 0 : user = cred->user;
329 0 : if (!who)
330 0 : uid = cred->uid;
331 0 : else if (!uid_eq(uid, cred->uid)) {
332 0 : user = find_user(uid);
333 0 : if (!user)
334 : goto out_unlock; /* No processes for this user */
335 : }
336 0 : for_each_process_thread(g, p) {
337 0 : if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) {
338 0 : niceval = nice_to_rlimit(task_nice(p));
339 0 : if (niceval > retval)
340 0 : retval = niceval;
341 : }
342 : }
343 0 : if (!uid_eq(uid, cred->uid))
344 0 : free_uid(user); /* for find_user() */
345 : break;
346 : }
347 : out_unlock:
348 : rcu_read_unlock();
349 :
350 0 : return retval;
351 : }
352 :
353 : /*
354 : * Unprivileged users may change the real gid to the effective gid
355 : * or vice versa. (BSD-style)
356 : *
357 : * If you set the real gid at all, or set the effective gid to a value not
358 : * equal to the real gid, then the saved gid is set to the new effective gid.
359 : *
360 : * This makes it possible for a setgid program to completely drop its
361 : * privileges, which is often a useful assertion to make when you are doing
362 : * a security audit over a program.
363 : *
364 : * The general idea is that a program which uses just setregid() will be
365 : * 100% compatible with BSD. A program which uses just setgid() will be
366 : * 100% compatible with POSIX with saved IDs.
367 : *
368 : * SMP: There are not races, the GIDs are checked only by filesystem
369 : * operations (as far as semantic preservation is concerned).
370 : */
371 : #ifdef CONFIG_MULTIUSER
372 0 : long __sys_setregid(gid_t rgid, gid_t egid)
373 : {
374 0 : struct user_namespace *ns = current_user_ns();
375 : const struct cred *old;
376 : struct cred *new;
377 : int retval;
378 : kgid_t krgid, kegid;
379 :
380 0 : krgid = make_kgid(ns, rgid);
381 0 : kegid = make_kgid(ns, egid);
382 :
383 : if ((rgid != (gid_t) -1) && !gid_valid(krgid))
384 : return -EINVAL;
385 : if ((egid != (gid_t) -1) && !gid_valid(kegid))
386 : return -EINVAL;
387 :
388 0 : new = prepare_creds();
389 0 : if (!new)
390 : return -ENOMEM;
391 0 : old = current_cred();
392 :
393 0 : retval = -EPERM;
394 0 : if (rgid != (gid_t) -1) {
395 0 : if (gid_eq(old->gid, krgid) ||
396 0 : gid_eq(old->egid, krgid) ||
397 0 : ns_capable_setid(old->user_ns, CAP_SETGID))
398 0 : new->gid = krgid;
399 : else
400 : goto error;
401 : }
402 0 : if (egid != (gid_t) -1) {
403 0 : if (gid_eq(old->gid, kegid) ||
404 0 : gid_eq(old->egid, kegid) ||
405 0 : gid_eq(old->sgid, kegid) ||
406 0 : ns_capable_setid(old->user_ns, CAP_SETGID))
407 0 : new->egid = kegid;
408 : else
409 : goto error;
410 : }
411 :
412 0 : if (rgid != (gid_t) -1 ||
413 0 : (egid != (gid_t) -1 && !gid_eq(kegid, old->gid)))
414 0 : new->sgid = new->egid;
415 0 : new->fsgid = new->egid;
416 :
417 0 : retval = security_task_fix_setgid(new, old, LSM_SETID_RE);
418 : if (retval < 0)
419 : goto error;
420 :
421 0 : return commit_creds(new);
422 :
423 : error:
424 0 : abort_creds(new);
425 0 : return retval;
426 : }
427 :
428 0 : SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
429 : {
430 0 : return __sys_setregid(rgid, egid);
431 : }
432 :
433 : /*
434 : * setgid() is implemented like SysV w/ SAVED_IDS
435 : *
436 : * SMP: Same implicit races as above.
437 : */
438 0 : long __sys_setgid(gid_t gid)
439 : {
440 0 : struct user_namespace *ns = current_user_ns();
441 : const struct cred *old;
442 : struct cred *new;
443 : int retval;
444 : kgid_t kgid;
445 :
446 0 : kgid = make_kgid(ns, gid);
447 0 : if (!gid_valid(kgid))
448 : return -EINVAL;
449 :
450 0 : new = prepare_creds();
451 0 : if (!new)
452 : return -ENOMEM;
453 0 : old = current_cred();
454 :
455 0 : retval = -EPERM;
456 0 : if (ns_capable_setid(old->user_ns, CAP_SETGID))
457 0 : new->gid = new->egid = new->sgid = new->fsgid = kgid;
458 0 : else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid))
459 0 : new->egid = new->fsgid = kgid;
460 : else
461 : goto error;
462 :
463 0 : retval = security_task_fix_setgid(new, old, LSM_SETID_ID);
464 : if (retval < 0)
465 : goto error;
466 :
467 0 : return commit_creds(new);
468 :
469 : error:
470 0 : abort_creds(new);
471 0 : return retval;
472 : }
473 :
474 0 : SYSCALL_DEFINE1(setgid, gid_t, gid)
475 : {
476 0 : return __sys_setgid(gid);
477 : }
478 :
479 : /*
480 : * change the user struct in a credentials set to match the new UID
481 : */
482 : static int set_user(struct cred *new)
483 : {
484 : struct user_struct *new_user;
485 :
486 0 : new_user = alloc_uid(new->uid);
487 0 : if (!new_user)
488 : return -EAGAIN;
489 :
490 0 : free_uid(new->user);
491 0 : new->user = new_user;
492 : return 0;
493 : }
494 :
495 0 : static void flag_nproc_exceeded(struct cred *new)
496 : {
497 0 : if (new->ucounts == current_ucounts())
498 : return;
499 :
500 : /*
501 : * We don't fail in case of NPROC limit excess here because too many
502 : * poorly written programs don't check set*uid() return code, assuming
503 : * it never fails if called by root. We may still enforce NPROC limit
504 : * for programs doing set*uid()+execve() by harmlessly deferring the
505 : * failure to the execve() stage.
506 : */
507 0 : if (is_rlimit_overlimit(new->ucounts, UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC)) &&
508 0 : new->user != INIT_USER)
509 0 : current->flags |= PF_NPROC_EXCEEDED;
510 : else
511 0 : current->flags &= ~PF_NPROC_EXCEEDED;
512 : }
513 :
514 : /*
515 : * Unprivileged users may change the real uid to the effective uid
516 : * or vice versa. (BSD-style)
517 : *
518 : * If you set the real uid at all, or set the effective uid to a value not
519 : * equal to the real uid, then the saved uid is set to the new effective uid.
520 : *
521 : * This makes it possible for a setuid program to completely drop its
522 : * privileges, which is often a useful assertion to make when you are doing
523 : * a security audit over a program.
524 : *
525 : * The general idea is that a program which uses just setreuid() will be
526 : * 100% compatible with BSD. A program which uses just setuid() will be
527 : * 100% compatible with POSIX with saved IDs.
528 : */
529 0 : long __sys_setreuid(uid_t ruid, uid_t euid)
530 : {
531 0 : struct user_namespace *ns = current_user_ns();
532 : const struct cred *old;
533 : struct cred *new;
534 : int retval;
535 : kuid_t kruid, keuid;
536 :
537 0 : kruid = make_kuid(ns, ruid);
538 0 : keuid = make_kuid(ns, euid);
539 :
540 : if ((ruid != (uid_t) -1) && !uid_valid(kruid))
541 : return -EINVAL;
542 : if ((euid != (uid_t) -1) && !uid_valid(keuid))
543 : return -EINVAL;
544 :
545 0 : new = prepare_creds();
546 0 : if (!new)
547 : return -ENOMEM;
548 0 : old = current_cred();
549 :
550 0 : retval = -EPERM;
551 0 : if (ruid != (uid_t) -1) {
552 0 : new->uid = kruid;
553 0 : if (!uid_eq(old->uid, kruid) &&
554 0 : !uid_eq(old->euid, kruid) &&
555 0 : !ns_capable_setid(old->user_ns, CAP_SETUID))
556 : goto error;
557 : }
558 :
559 0 : if (euid != (uid_t) -1) {
560 0 : new->euid = keuid;
561 0 : if (!uid_eq(old->uid, keuid) &&
562 0 : !uid_eq(old->euid, keuid) &&
563 0 : !uid_eq(old->suid, keuid) &&
564 0 : !ns_capable_setid(old->user_ns, CAP_SETUID))
565 : goto error;
566 : }
567 :
568 0 : if (!uid_eq(new->uid, old->uid)) {
569 0 : retval = set_user(new);
570 0 : if (retval < 0)
571 : goto error;
572 : }
573 0 : if (ruid != (uid_t) -1 ||
574 0 : (euid != (uid_t) -1 && !uid_eq(keuid, old->uid)))
575 0 : new->suid = new->euid;
576 0 : new->fsuid = new->euid;
577 :
578 0 : retval = security_task_fix_setuid(new, old, LSM_SETID_RE);
579 0 : if (retval < 0)
580 : goto error;
581 :
582 0 : retval = set_cred_ucounts(new);
583 0 : if (retval < 0)
584 : goto error;
585 :
586 0 : flag_nproc_exceeded(new);
587 0 : return commit_creds(new);
588 :
589 : error:
590 0 : abort_creds(new);
591 0 : return retval;
592 : }
593 :
594 0 : SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
595 : {
596 0 : return __sys_setreuid(ruid, euid);
597 : }
598 :
599 : /*
600 : * setuid() is implemented like SysV with SAVED_IDS
601 : *
602 : * Note that SAVED_ID's is deficient in that a setuid root program
603 : * like sendmail, for example, cannot set its uid to be a normal
604 : * user and then switch back, because if you're root, setuid() sets
605 : * the saved uid too. If you don't like this, blame the bright people
606 : * in the POSIX committee and/or USG. Note that the BSD-style setreuid()
607 : * will allow a root program to temporarily drop privileges and be able to
608 : * regain them by swapping the real and effective uid.
609 : */
610 0 : long __sys_setuid(uid_t uid)
611 : {
612 0 : struct user_namespace *ns = current_user_ns();
613 : const struct cred *old;
614 : struct cred *new;
615 : int retval;
616 : kuid_t kuid;
617 :
618 0 : kuid = make_kuid(ns, uid);
619 0 : if (!uid_valid(kuid))
620 : return -EINVAL;
621 :
622 0 : new = prepare_creds();
623 0 : if (!new)
624 : return -ENOMEM;
625 0 : old = current_cred();
626 :
627 0 : retval = -EPERM;
628 0 : if (ns_capable_setid(old->user_ns, CAP_SETUID)) {
629 0 : new->suid = new->uid = kuid;
630 0 : if (!uid_eq(kuid, old->uid)) {
631 0 : retval = set_user(new);
632 0 : if (retval < 0)
633 : goto error;
634 : }
635 0 : } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) {
636 : goto error;
637 : }
638 :
639 0 : new->fsuid = new->euid = kuid;
640 :
641 0 : retval = security_task_fix_setuid(new, old, LSM_SETID_ID);
642 0 : if (retval < 0)
643 : goto error;
644 :
645 0 : retval = set_cred_ucounts(new);
646 0 : if (retval < 0)
647 : goto error;
648 :
649 0 : flag_nproc_exceeded(new);
650 0 : return commit_creds(new);
651 :
652 : error:
653 0 : abort_creds(new);
654 0 : return retval;
655 : }
656 :
657 0 : SYSCALL_DEFINE1(setuid, uid_t, uid)
658 : {
659 0 : return __sys_setuid(uid);
660 : }
661 :
662 :
663 : /*
664 : * This function implements a generic ability to update ruid, euid,
665 : * and suid. This allows you to implement the 4.4 compatible seteuid().
666 : */
667 0 : long __sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
668 : {
669 0 : struct user_namespace *ns = current_user_ns();
670 : const struct cred *old;
671 : struct cred *new;
672 : int retval;
673 : kuid_t kruid, keuid, ksuid;
674 : bool ruid_new, euid_new, suid_new;
675 :
676 0 : kruid = make_kuid(ns, ruid);
677 0 : keuid = make_kuid(ns, euid);
678 0 : ksuid = make_kuid(ns, suid);
679 :
680 : if ((ruid != (uid_t) -1) && !uid_valid(kruid))
681 : return -EINVAL;
682 :
683 : if ((euid != (uid_t) -1) && !uid_valid(keuid))
684 : return -EINVAL;
685 :
686 : if ((suid != (uid_t) -1) && !uid_valid(ksuid))
687 : return -EINVAL;
688 :
689 0 : old = current_cred();
690 :
691 : /* check for no-op */
692 0 : if ((ruid == (uid_t) -1 || uid_eq(kruid, old->uid)) &&
693 0 : (euid == (uid_t) -1 || (uid_eq(keuid, old->euid) &&
694 0 : uid_eq(keuid, old->fsuid))) &&
695 0 : (suid == (uid_t) -1 || uid_eq(ksuid, old->suid)))
696 : return 0;
697 :
698 0 : ruid_new = ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) &&
699 0 : !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid);
700 0 : euid_new = euid != (uid_t) -1 && !uid_eq(keuid, old->uid) &&
701 0 : !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid);
702 0 : suid_new = suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) &&
703 0 : !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid);
704 0 : if ((ruid_new || euid_new || suid_new) &&
705 0 : !ns_capable_setid(old->user_ns, CAP_SETUID))
706 : return -EPERM;
707 :
708 0 : new = prepare_creds();
709 0 : if (!new)
710 : return -ENOMEM;
711 :
712 0 : if (ruid != (uid_t) -1) {
713 0 : new->uid = kruid;
714 0 : if (!uid_eq(kruid, old->uid)) {
715 0 : retval = set_user(new);
716 0 : if (retval < 0)
717 : goto error;
718 : }
719 : }
720 0 : if (euid != (uid_t) -1)
721 0 : new->euid = keuid;
722 0 : if (suid != (uid_t) -1)
723 0 : new->suid = ksuid;
724 0 : new->fsuid = new->euid;
725 :
726 0 : retval = security_task_fix_setuid(new, old, LSM_SETID_RES);
727 0 : if (retval < 0)
728 : goto error;
729 :
730 0 : retval = set_cred_ucounts(new);
731 0 : if (retval < 0)
732 : goto error;
733 :
734 0 : flag_nproc_exceeded(new);
735 0 : return commit_creds(new);
736 :
737 : error:
738 0 : abort_creds(new);
739 0 : return retval;
740 : }
741 :
742 0 : SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid)
743 : {
744 0 : return __sys_setresuid(ruid, euid, suid);
745 : }
746 :
747 0 : SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp)
748 : {
749 0 : const struct cred *cred = current_cred();
750 : int retval;
751 : uid_t ruid, euid, suid;
752 :
753 0 : ruid = from_kuid_munged(cred->user_ns, cred->uid);
754 0 : euid = from_kuid_munged(cred->user_ns, cred->euid);
755 0 : suid = from_kuid_munged(cred->user_ns, cred->suid);
756 :
757 0 : retval = put_user(ruid, ruidp);
758 0 : if (!retval) {
759 0 : retval = put_user(euid, euidp);
760 0 : if (!retval)
761 0 : return put_user(suid, suidp);
762 : }
763 0 : return retval;
764 : }
765 :
766 : /*
767 : * Same as above, but for rgid, egid, sgid.
768 : */
769 0 : long __sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
770 : {
771 0 : struct user_namespace *ns = current_user_ns();
772 : const struct cred *old;
773 : struct cred *new;
774 : int retval;
775 : kgid_t krgid, kegid, ksgid;
776 : bool rgid_new, egid_new, sgid_new;
777 :
778 0 : krgid = make_kgid(ns, rgid);
779 0 : kegid = make_kgid(ns, egid);
780 0 : ksgid = make_kgid(ns, sgid);
781 :
782 : if ((rgid != (gid_t) -1) && !gid_valid(krgid))
783 : return -EINVAL;
784 : if ((egid != (gid_t) -1) && !gid_valid(kegid))
785 : return -EINVAL;
786 : if ((sgid != (gid_t) -1) && !gid_valid(ksgid))
787 : return -EINVAL;
788 :
789 0 : old = current_cred();
790 :
791 : /* check for no-op */
792 0 : if ((rgid == (gid_t) -1 || gid_eq(krgid, old->gid)) &&
793 0 : (egid == (gid_t) -1 || (gid_eq(kegid, old->egid) &&
794 0 : gid_eq(kegid, old->fsgid))) &&
795 0 : (sgid == (gid_t) -1 || gid_eq(ksgid, old->sgid)))
796 : return 0;
797 :
798 0 : rgid_new = rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) &&
799 0 : !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid);
800 0 : egid_new = egid != (gid_t) -1 && !gid_eq(kegid, old->gid) &&
801 0 : !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid);
802 0 : sgid_new = sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) &&
803 0 : !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid);
804 0 : if ((rgid_new || egid_new || sgid_new) &&
805 0 : !ns_capable_setid(old->user_ns, CAP_SETGID))
806 : return -EPERM;
807 :
808 0 : new = prepare_creds();
809 0 : if (!new)
810 : return -ENOMEM;
811 :
812 0 : if (rgid != (gid_t) -1)
813 0 : new->gid = krgid;
814 0 : if (egid != (gid_t) -1)
815 0 : new->egid = kegid;
816 0 : if (sgid != (gid_t) -1)
817 0 : new->sgid = ksgid;
818 0 : new->fsgid = new->egid;
819 :
820 0 : retval = security_task_fix_setgid(new, old, LSM_SETID_RES);
821 : if (retval < 0)
822 : goto error;
823 :
824 0 : return commit_creds(new);
825 :
826 : error:
827 : abort_creds(new);
828 : return retval;
829 : }
830 :
831 0 : SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid)
832 : {
833 0 : return __sys_setresgid(rgid, egid, sgid);
834 : }
835 :
836 0 : SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp)
837 : {
838 0 : const struct cred *cred = current_cred();
839 : int retval;
840 : gid_t rgid, egid, sgid;
841 :
842 0 : rgid = from_kgid_munged(cred->user_ns, cred->gid);
843 0 : egid = from_kgid_munged(cred->user_ns, cred->egid);
844 0 : sgid = from_kgid_munged(cred->user_ns, cred->sgid);
845 :
846 0 : retval = put_user(rgid, rgidp);
847 0 : if (!retval) {
848 0 : retval = put_user(egid, egidp);
849 0 : if (!retval)
850 0 : retval = put_user(sgid, sgidp);
851 : }
852 :
853 0 : return retval;
854 : }
855 :
856 :
857 : /*
858 : * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This
859 : * is used for "access()" and for the NFS daemon (letting nfsd stay at
860 : * whatever uid it wants to). It normally shadows "euid", except when
861 : * explicitly set by setfsuid() or for access..
862 : */
863 0 : long __sys_setfsuid(uid_t uid)
864 : {
865 : const struct cred *old;
866 : struct cred *new;
867 : uid_t old_fsuid;
868 : kuid_t kuid;
869 :
870 0 : old = current_cred();
871 0 : old_fsuid = from_kuid_munged(old->user_ns, old->fsuid);
872 :
873 0 : kuid = make_kuid(old->user_ns, uid);
874 0 : if (!uid_valid(kuid))
875 0 : return old_fsuid;
876 :
877 0 : new = prepare_creds();
878 0 : if (!new)
879 0 : return old_fsuid;
880 :
881 0 : if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) ||
882 0 : uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) ||
883 0 : ns_capable_setid(old->user_ns, CAP_SETUID)) {
884 0 : if (!uid_eq(kuid, old->fsuid)) {
885 0 : new->fsuid = kuid;
886 0 : if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0)
887 : goto change_okay;
888 : }
889 : }
890 :
891 0 : abort_creds(new);
892 0 : return old_fsuid;
893 :
894 : change_okay:
895 0 : commit_creds(new);
896 0 : return old_fsuid;
897 : }
898 :
899 0 : SYSCALL_DEFINE1(setfsuid, uid_t, uid)
900 : {
901 0 : return __sys_setfsuid(uid);
902 : }
903 :
904 : /*
905 : * Samma på svenska..
906 : */
907 0 : long __sys_setfsgid(gid_t gid)
908 : {
909 : const struct cred *old;
910 : struct cred *new;
911 : gid_t old_fsgid;
912 : kgid_t kgid;
913 :
914 0 : old = current_cred();
915 0 : old_fsgid = from_kgid_munged(old->user_ns, old->fsgid);
916 :
917 0 : kgid = make_kgid(old->user_ns, gid);
918 0 : if (!gid_valid(kgid))
919 0 : return old_fsgid;
920 :
921 0 : new = prepare_creds();
922 0 : if (!new)
923 0 : return old_fsgid;
924 :
925 0 : if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) ||
926 0 : gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) ||
927 0 : ns_capable_setid(old->user_ns, CAP_SETGID)) {
928 0 : if (!gid_eq(kgid, old->fsgid)) {
929 0 : new->fsgid = kgid;
930 0 : if (security_task_fix_setgid(new,old,LSM_SETID_FS) == 0)
931 : goto change_okay;
932 : }
933 : }
934 :
935 0 : abort_creds(new);
936 0 : return old_fsgid;
937 :
938 : change_okay:
939 0 : commit_creds(new);
940 0 : return old_fsgid;
941 : }
942 :
943 0 : SYSCALL_DEFINE1(setfsgid, gid_t, gid)
944 : {
945 0 : return __sys_setfsgid(gid);
946 : }
947 : #endif /* CONFIG_MULTIUSER */
948 :
949 : /**
950 : * sys_getpid - return the thread group id of the current process
951 : *
952 : * Note, despite the name, this returns the tgid not the pid. The tgid and
953 : * the pid are identical unless CLONE_THREAD was specified on clone() in
954 : * which case the tgid is the same in all threads of the same group.
955 : *
956 : * This is SMP safe as current->tgid does not change.
957 : */
958 0 : SYSCALL_DEFINE0(getpid)
959 : {
960 0 : return task_tgid_vnr(current);
961 : }
962 :
963 : /* Thread ID - the internal kernel "pid" */
964 0 : SYSCALL_DEFINE0(gettid)
965 : {
966 0 : return task_pid_vnr(current);
967 : }
968 :
969 : /*
970 : * Accessing ->real_parent is not SMP-safe, it could
971 : * change from under us. However, we can use a stale
972 : * value of ->real_parent under rcu_read_lock(), see
973 : * release_task()->call_rcu(delayed_put_task_struct).
974 : */
975 0 : SYSCALL_DEFINE0(getppid)
976 : {
977 : int pid;
978 :
979 : rcu_read_lock();
980 0 : pid = task_tgid_vnr(rcu_dereference(current->real_parent));
981 : rcu_read_unlock();
982 :
983 0 : return pid;
984 : }
985 :
986 0 : SYSCALL_DEFINE0(getuid)
987 : {
988 : /* Only we change this so SMP safe */
989 0 : return from_kuid_munged(current_user_ns(), current_uid());
990 : }
991 :
992 0 : SYSCALL_DEFINE0(geteuid)
993 : {
994 : /* Only we change this so SMP safe */
995 0 : return from_kuid_munged(current_user_ns(), current_euid());
996 : }
997 :
998 0 : SYSCALL_DEFINE0(getgid)
999 : {
1000 : /* Only we change this so SMP safe */
1001 0 : return from_kgid_munged(current_user_ns(), current_gid());
1002 : }
1003 :
1004 0 : SYSCALL_DEFINE0(getegid)
1005 : {
1006 : /* Only we change this so SMP safe */
1007 0 : return from_kgid_munged(current_user_ns(), current_egid());
1008 : }
1009 :
1010 0 : static void do_sys_times(struct tms *tms)
1011 : {
1012 : u64 tgutime, tgstime, cutime, cstime;
1013 :
1014 0 : thread_group_cputime_adjusted(current, &tgutime, &tgstime);
1015 0 : cutime = current->signal->cutime;
1016 0 : cstime = current->signal->cstime;
1017 0 : tms->tms_utime = nsec_to_clock_t(tgutime);
1018 0 : tms->tms_stime = nsec_to_clock_t(tgstime);
1019 0 : tms->tms_cutime = nsec_to_clock_t(cutime);
1020 0 : tms->tms_cstime = nsec_to_clock_t(cstime);
1021 0 : }
1022 :
1023 0 : SYSCALL_DEFINE1(times, struct tms __user *, tbuf)
1024 : {
1025 0 : if (tbuf) {
1026 : struct tms tmp;
1027 :
1028 0 : do_sys_times(&tmp);
1029 0 : if (copy_to_user(tbuf, &tmp, sizeof(struct tms)))
1030 0 : return -EFAULT;
1031 : }
1032 : force_successful_syscall_return();
1033 0 : return (long) jiffies_64_to_clock_t(get_jiffies_64());
1034 : }
1035 :
1036 : #ifdef CONFIG_COMPAT
1037 : static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
1038 : {
1039 : return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
1040 : }
1041 :
1042 : COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
1043 : {
1044 : if (tbuf) {
1045 : struct tms tms;
1046 : struct compat_tms tmp;
1047 :
1048 : do_sys_times(&tms);
1049 : /* Convert our struct tms to the compat version. */
1050 : tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
1051 : tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
1052 : tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
1053 : tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
1054 : if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
1055 : return -EFAULT;
1056 : }
1057 : force_successful_syscall_return();
1058 : return compat_jiffies_to_clock_t(jiffies);
1059 : }
1060 : #endif
1061 :
1062 : /*
1063 : * This needs some heavy checking ...
1064 : * I just haven't the stomach for it. I also don't fully
1065 : * understand sessions/pgrp etc. Let somebody who does explain it.
1066 : *
1067 : * OK, I think I have the protection semantics right.... this is really
1068 : * only important on a multi-user system anyway, to make sure one user
1069 : * can't send a signal to a process owned by another. -TYT, 12/12/91
1070 : *
1071 : * !PF_FORKNOEXEC check to conform completely to POSIX.
1072 : */
1073 0 : SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid)
1074 : {
1075 : struct task_struct *p;
1076 0 : struct task_struct *group_leader = current->group_leader;
1077 : struct pid *pgrp;
1078 : int err;
1079 :
1080 0 : if (!pid)
1081 0 : pid = task_pid_vnr(group_leader);
1082 0 : if (!pgid)
1083 0 : pgid = pid;
1084 0 : if (pgid < 0)
1085 : return -EINVAL;
1086 : rcu_read_lock();
1087 :
1088 : /* From this point forward we keep holding onto the tasklist lock
1089 : * so that our parent does not change from under us. -DaveM
1090 : */
1091 0 : write_lock_irq(&tasklist_lock);
1092 :
1093 0 : err = -ESRCH;
1094 0 : p = find_task_by_vpid(pid);
1095 0 : if (!p)
1096 : goto out;
1097 :
1098 0 : err = -EINVAL;
1099 0 : if (!thread_group_leader(p))
1100 : goto out;
1101 :
1102 0 : if (same_thread_group(p->real_parent, group_leader)) {
1103 0 : err = -EPERM;
1104 0 : if (task_session(p) != task_session(group_leader))
1105 : goto out;
1106 0 : err = -EACCES;
1107 0 : if (!(p->flags & PF_FORKNOEXEC))
1108 : goto out;
1109 : } else {
1110 0 : err = -ESRCH;
1111 0 : if (p != group_leader)
1112 : goto out;
1113 : }
1114 :
1115 0 : err = -EPERM;
1116 0 : if (p->signal->leader)
1117 : goto out;
1118 :
1119 0 : pgrp = task_pid(p);
1120 0 : if (pgid != pid) {
1121 : struct task_struct *g;
1122 :
1123 0 : pgrp = find_vpid(pgid);
1124 0 : g = pid_task(pgrp, PIDTYPE_PGID);
1125 0 : if (!g || task_session(g) != task_session(group_leader))
1126 : goto out;
1127 : }
1128 :
1129 0 : err = security_task_setpgid(p, pgid);
1130 : if (err)
1131 : goto out;
1132 :
1133 0 : if (task_pgrp(p) != pgrp)
1134 0 : change_pid(p, PIDTYPE_PGID, pgrp);
1135 :
1136 : err = 0;
1137 : out:
1138 : /* All paths lead to here, thus we are safe. -DaveM */
1139 0 : write_unlock_irq(&tasklist_lock);
1140 : rcu_read_unlock();
1141 0 : return err;
1142 : }
1143 :
1144 0 : static int do_getpgid(pid_t pid)
1145 : {
1146 : struct task_struct *p;
1147 : struct pid *grp;
1148 : int retval;
1149 :
1150 : rcu_read_lock();
1151 0 : if (!pid)
1152 0 : grp = task_pgrp(current);
1153 : else {
1154 0 : retval = -ESRCH;
1155 0 : p = find_task_by_vpid(pid);
1156 0 : if (!p)
1157 : goto out;
1158 0 : grp = task_pgrp(p);
1159 0 : if (!grp)
1160 : goto out;
1161 :
1162 : retval = security_task_getpgid(p);
1163 : if (retval)
1164 : goto out;
1165 : }
1166 0 : retval = pid_vnr(grp);
1167 : out:
1168 : rcu_read_unlock();
1169 0 : return retval;
1170 : }
1171 :
1172 0 : SYSCALL_DEFINE1(getpgid, pid_t, pid)
1173 : {
1174 0 : return do_getpgid(pid);
1175 : }
1176 :
1177 : #ifdef __ARCH_WANT_SYS_GETPGRP
1178 :
1179 0 : SYSCALL_DEFINE0(getpgrp)
1180 : {
1181 0 : return do_getpgid(0);
1182 : }
1183 :
1184 : #endif
1185 :
1186 0 : SYSCALL_DEFINE1(getsid, pid_t, pid)
1187 : {
1188 : struct task_struct *p;
1189 : struct pid *sid;
1190 : int retval;
1191 :
1192 : rcu_read_lock();
1193 0 : if (!pid)
1194 0 : sid = task_session(current);
1195 : else {
1196 0 : retval = -ESRCH;
1197 0 : p = find_task_by_vpid(pid);
1198 0 : if (!p)
1199 : goto out;
1200 0 : sid = task_session(p);
1201 0 : if (!sid)
1202 : goto out;
1203 :
1204 : retval = security_task_getsid(p);
1205 : if (retval)
1206 : goto out;
1207 : }
1208 0 : retval = pid_vnr(sid);
1209 : out:
1210 : rcu_read_unlock();
1211 0 : return retval;
1212 : }
1213 :
1214 0 : static void set_special_pids(struct pid *pid)
1215 : {
1216 0 : struct task_struct *curr = current->group_leader;
1217 :
1218 0 : if (task_session(curr) != pid)
1219 0 : change_pid(curr, PIDTYPE_SID, pid);
1220 :
1221 0 : if (task_pgrp(curr) != pid)
1222 0 : change_pid(curr, PIDTYPE_PGID, pid);
1223 0 : }
1224 :
1225 0 : int ksys_setsid(void)
1226 : {
1227 0 : struct task_struct *group_leader = current->group_leader;
1228 0 : struct pid *sid = task_pid(group_leader);
1229 0 : pid_t session = pid_vnr(sid);
1230 0 : int err = -EPERM;
1231 :
1232 0 : write_lock_irq(&tasklist_lock);
1233 : /* Fail if I am already a session leader */
1234 0 : if (group_leader->signal->leader)
1235 : goto out;
1236 :
1237 : /* Fail if a process group id already exists that equals the
1238 : * proposed session id.
1239 : */
1240 0 : if (pid_task(sid, PIDTYPE_PGID))
1241 : goto out;
1242 :
1243 0 : group_leader->signal->leader = 1;
1244 0 : set_special_pids(sid);
1245 :
1246 0 : proc_clear_tty(group_leader);
1247 :
1248 0 : err = session;
1249 : out:
1250 0 : write_unlock_irq(&tasklist_lock);
1251 : if (err > 0) {
1252 : proc_sid_connector(group_leader);
1253 : sched_autogroup_create_attach(group_leader);
1254 : }
1255 0 : return err;
1256 : }
1257 :
1258 0 : SYSCALL_DEFINE0(setsid)
1259 : {
1260 0 : return ksys_setsid();
1261 : }
1262 :
1263 : DECLARE_RWSEM(uts_sem);
1264 :
1265 : #ifdef COMPAT_UTS_MACHINE
1266 : #define override_architecture(name) \
1267 : (personality(current->personality) == PER_LINUX32 && \
1268 : copy_to_user(name->machine, COMPAT_UTS_MACHINE, \
1269 : sizeof(COMPAT_UTS_MACHINE)))
1270 : #else
1271 : #define override_architecture(name) 0
1272 : #endif
1273 :
1274 : /*
1275 : * Work around broken programs that cannot handle "Linux 3.0".
1276 : * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
1277 : * And we map 4.x and later versions to 2.6.60+x, so 4.0/5.0/6.0/... would be
1278 : * 2.6.60.
1279 : */
1280 0 : static int override_release(char __user *release, size_t len)
1281 : {
1282 0 : int ret = 0;
1283 :
1284 0 : if (current->personality & UNAME26) {
1285 0 : const char *rest = UTS_RELEASE;
1286 0 : char buf[65] = { 0 };
1287 0 : int ndots = 0;
1288 : unsigned v;
1289 : size_t copy;
1290 :
1291 0 : while (*rest) {
1292 0 : if (*rest == '.' && ++ndots >= 3)
1293 : break;
1294 0 : if (!isdigit(*rest) && *rest != '.')
1295 : break;
1296 0 : rest++;
1297 : }
1298 0 : v = LINUX_VERSION_PATCHLEVEL + 60;
1299 0 : copy = clamp_t(size_t, len, 1, sizeof(buf));
1300 0 : copy = scnprintf(buf, copy, "2.6.%u%s", v, rest);
1301 0 : ret = copy_to_user(release, buf, copy + 1);
1302 : }
1303 0 : return ret;
1304 : }
1305 :
1306 0 : SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
1307 : {
1308 : struct new_utsname tmp;
1309 :
1310 0 : down_read(&uts_sem);
1311 0 : memcpy(&tmp, utsname(), sizeof(tmp));
1312 0 : up_read(&uts_sem);
1313 0 : if (copy_to_user(name, &tmp, sizeof(tmp)))
1314 : return -EFAULT;
1315 :
1316 0 : if (override_release(name->release, sizeof(name->release)))
1317 : return -EFAULT;
1318 : if (override_architecture(name))
1319 : return -EFAULT;
1320 0 : return 0;
1321 : }
1322 :
1323 : #ifdef __ARCH_WANT_SYS_OLD_UNAME
1324 : /*
1325 : * Old cruft
1326 : */
1327 0 : SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
1328 : {
1329 : struct old_utsname tmp;
1330 :
1331 0 : if (!name)
1332 : return -EFAULT;
1333 :
1334 0 : down_read(&uts_sem);
1335 0 : memcpy(&tmp, utsname(), sizeof(tmp));
1336 0 : up_read(&uts_sem);
1337 0 : if (copy_to_user(name, &tmp, sizeof(tmp)))
1338 : return -EFAULT;
1339 :
1340 0 : if (override_release(name->release, sizeof(name->release)))
1341 : return -EFAULT;
1342 : if (override_architecture(name))
1343 : return -EFAULT;
1344 0 : return 0;
1345 : }
1346 :
1347 0 : SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
1348 : {
1349 : struct oldold_utsname tmp;
1350 :
1351 0 : if (!name)
1352 : return -EFAULT;
1353 :
1354 0 : memset(&tmp, 0, sizeof(tmp));
1355 :
1356 0 : down_read(&uts_sem);
1357 0 : memcpy(&tmp.sysname, &utsname()->sysname, __OLD_UTS_LEN);
1358 0 : memcpy(&tmp.nodename, &utsname()->nodename, __OLD_UTS_LEN);
1359 0 : memcpy(&tmp.release, &utsname()->release, __OLD_UTS_LEN);
1360 0 : memcpy(&tmp.version, &utsname()->version, __OLD_UTS_LEN);
1361 0 : memcpy(&tmp.machine, &utsname()->machine, __OLD_UTS_LEN);
1362 0 : up_read(&uts_sem);
1363 0 : if (copy_to_user(name, &tmp, sizeof(tmp)))
1364 : return -EFAULT;
1365 :
1366 : if (override_architecture(name))
1367 : return -EFAULT;
1368 0 : if (override_release(name->release, sizeof(name->release)))
1369 : return -EFAULT;
1370 0 : return 0;
1371 : }
1372 : #endif
1373 :
1374 0 : SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
1375 : {
1376 : int errno;
1377 : char tmp[__NEW_UTS_LEN];
1378 :
1379 0 : if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1380 : return -EPERM;
1381 :
1382 0 : if (len < 0 || len > __NEW_UTS_LEN)
1383 : return -EINVAL;
1384 0 : errno = -EFAULT;
1385 0 : if (!copy_from_user(tmp, name, len)) {
1386 : struct new_utsname *u;
1387 :
1388 0 : add_device_randomness(tmp, len);
1389 0 : down_write(&uts_sem);
1390 0 : u = utsname();
1391 0 : memcpy(u->nodename, tmp, len);
1392 0 : memset(u->nodename + len, 0, sizeof(u->nodename) - len);
1393 0 : errno = 0;
1394 0 : uts_proc_notify(UTS_PROC_HOSTNAME);
1395 0 : up_write(&uts_sem);
1396 : }
1397 0 : return errno;
1398 : }
1399 :
1400 : #ifdef __ARCH_WANT_SYS_GETHOSTNAME
1401 :
1402 0 : SYSCALL_DEFINE2(gethostname, char __user *, name, int, len)
1403 : {
1404 : int i;
1405 : struct new_utsname *u;
1406 : char tmp[__NEW_UTS_LEN + 1];
1407 :
1408 0 : if (len < 0)
1409 : return -EINVAL;
1410 0 : down_read(&uts_sem);
1411 0 : u = utsname();
1412 0 : i = 1 + strlen(u->nodename);
1413 0 : if (i > len)
1414 0 : i = len;
1415 0 : memcpy(tmp, u->nodename, i);
1416 0 : up_read(&uts_sem);
1417 0 : if (copy_to_user(name, tmp, i))
1418 : return -EFAULT;
1419 0 : return 0;
1420 : }
1421 :
1422 : #endif
1423 :
1424 : /*
1425 : * Only setdomainname; getdomainname can be implemented by calling
1426 : * uname()
1427 : */
1428 0 : SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len)
1429 : {
1430 : int errno;
1431 : char tmp[__NEW_UTS_LEN];
1432 :
1433 0 : if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1434 : return -EPERM;
1435 0 : if (len < 0 || len > __NEW_UTS_LEN)
1436 : return -EINVAL;
1437 :
1438 0 : errno = -EFAULT;
1439 0 : if (!copy_from_user(tmp, name, len)) {
1440 : struct new_utsname *u;
1441 :
1442 0 : add_device_randomness(tmp, len);
1443 0 : down_write(&uts_sem);
1444 0 : u = utsname();
1445 0 : memcpy(u->domainname, tmp, len);
1446 0 : memset(u->domainname + len, 0, sizeof(u->domainname) - len);
1447 0 : errno = 0;
1448 0 : uts_proc_notify(UTS_PROC_DOMAINNAME);
1449 0 : up_write(&uts_sem);
1450 : }
1451 0 : return errno;
1452 : }
1453 :
1454 : /* make sure you are allowed to change @tsk limits before calling this */
1455 0 : static int do_prlimit(struct task_struct *tsk, unsigned int resource,
1456 : struct rlimit *new_rlim, struct rlimit *old_rlim)
1457 : {
1458 : struct rlimit *rlim;
1459 0 : int retval = 0;
1460 :
1461 0 : if (resource >= RLIM_NLIMITS)
1462 : return -EINVAL;
1463 0 : resource = array_index_nospec(resource, RLIM_NLIMITS);
1464 :
1465 0 : if (new_rlim) {
1466 0 : if (new_rlim->rlim_cur > new_rlim->rlim_max)
1467 : return -EINVAL;
1468 0 : if (resource == RLIMIT_NOFILE &&
1469 0 : new_rlim->rlim_max > sysctl_nr_open)
1470 : return -EPERM;
1471 : }
1472 :
1473 : /* Holding a refcount on tsk protects tsk->signal from disappearing. */
1474 0 : rlim = tsk->signal->rlim + resource;
1475 0 : task_lock(tsk->group_leader);
1476 0 : if (new_rlim) {
1477 : /*
1478 : * Keep the capable check against init_user_ns until cgroups can
1479 : * contain all limits.
1480 : */
1481 0 : if (new_rlim->rlim_max > rlim->rlim_max &&
1482 0 : !capable(CAP_SYS_RESOURCE))
1483 0 : retval = -EPERM;
1484 0 : if (!retval)
1485 0 : retval = security_task_setrlimit(tsk, resource, new_rlim);
1486 : }
1487 0 : if (!retval) {
1488 0 : if (old_rlim)
1489 0 : *old_rlim = *rlim;
1490 0 : if (new_rlim)
1491 0 : *rlim = *new_rlim;
1492 : }
1493 0 : task_unlock(tsk->group_leader);
1494 :
1495 : /*
1496 : * RLIMIT_CPU handling. Arm the posix CPU timer if the limit is not
1497 : * infinite. In case of RLIM_INFINITY the posix CPU timer code
1498 : * ignores the rlimit.
1499 : */
1500 0 : if (!retval && new_rlim && resource == RLIMIT_CPU &&
1501 0 : new_rlim->rlim_cur != RLIM_INFINITY &&
1502 : IS_ENABLED(CONFIG_POSIX_TIMERS)) {
1503 : /*
1504 : * update_rlimit_cpu can fail if the task is exiting, but there
1505 : * may be other tasks in the thread group that are not exiting,
1506 : * and they need their cpu timers adjusted.
1507 : *
1508 : * The group_leader is the last task to be released, so if we
1509 : * cannot update_rlimit_cpu on it, then the entire process is
1510 : * exiting and we do not need to update at all.
1511 : */
1512 0 : update_rlimit_cpu(tsk->group_leader, new_rlim->rlim_cur);
1513 : }
1514 :
1515 : return retval;
1516 : }
1517 :
1518 0 : SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1519 : {
1520 : struct rlimit value;
1521 : int ret;
1522 :
1523 0 : ret = do_prlimit(current, resource, NULL, &value);
1524 0 : if (!ret)
1525 0 : ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0;
1526 :
1527 0 : return ret;
1528 : }
1529 :
1530 : #ifdef CONFIG_COMPAT
1531 :
1532 : COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
1533 : struct compat_rlimit __user *, rlim)
1534 : {
1535 : struct rlimit r;
1536 : struct compat_rlimit r32;
1537 :
1538 : if (copy_from_user(&r32, rlim, sizeof(struct compat_rlimit)))
1539 : return -EFAULT;
1540 :
1541 : if (r32.rlim_cur == COMPAT_RLIM_INFINITY)
1542 : r.rlim_cur = RLIM_INFINITY;
1543 : else
1544 : r.rlim_cur = r32.rlim_cur;
1545 : if (r32.rlim_max == COMPAT_RLIM_INFINITY)
1546 : r.rlim_max = RLIM_INFINITY;
1547 : else
1548 : r.rlim_max = r32.rlim_max;
1549 : return do_prlimit(current, resource, &r, NULL);
1550 : }
1551 :
1552 : COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
1553 : struct compat_rlimit __user *, rlim)
1554 : {
1555 : struct rlimit r;
1556 : int ret;
1557 :
1558 : ret = do_prlimit(current, resource, NULL, &r);
1559 : if (!ret) {
1560 : struct compat_rlimit r32;
1561 : if (r.rlim_cur > COMPAT_RLIM_INFINITY)
1562 : r32.rlim_cur = COMPAT_RLIM_INFINITY;
1563 : else
1564 : r32.rlim_cur = r.rlim_cur;
1565 : if (r.rlim_max > COMPAT_RLIM_INFINITY)
1566 : r32.rlim_max = COMPAT_RLIM_INFINITY;
1567 : else
1568 : r32.rlim_max = r.rlim_max;
1569 :
1570 : if (copy_to_user(rlim, &r32, sizeof(struct compat_rlimit)))
1571 : return -EFAULT;
1572 : }
1573 : return ret;
1574 : }
1575 :
1576 : #endif
1577 :
1578 : #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
1579 :
1580 : /*
1581 : * Back compatibility for getrlimit. Needed for some apps.
1582 : */
1583 0 : SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1584 : struct rlimit __user *, rlim)
1585 : {
1586 : struct rlimit x;
1587 0 : if (resource >= RLIM_NLIMITS)
1588 : return -EINVAL;
1589 :
1590 0 : resource = array_index_nospec(resource, RLIM_NLIMITS);
1591 0 : task_lock(current->group_leader);
1592 0 : x = current->signal->rlim[resource];
1593 0 : task_unlock(current->group_leader);
1594 0 : if (x.rlim_cur > 0x7FFFFFFF)
1595 0 : x.rlim_cur = 0x7FFFFFFF;
1596 0 : if (x.rlim_max > 0x7FFFFFFF)
1597 0 : x.rlim_max = 0x7FFFFFFF;
1598 0 : return copy_to_user(rlim, &x, sizeof(x)) ? -EFAULT : 0;
1599 : }
1600 :
1601 : #ifdef CONFIG_COMPAT
1602 : COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1603 : struct compat_rlimit __user *, rlim)
1604 : {
1605 : struct rlimit r;
1606 :
1607 : if (resource >= RLIM_NLIMITS)
1608 : return -EINVAL;
1609 :
1610 : resource = array_index_nospec(resource, RLIM_NLIMITS);
1611 : task_lock(current->group_leader);
1612 : r = current->signal->rlim[resource];
1613 : task_unlock(current->group_leader);
1614 : if (r.rlim_cur > 0x7FFFFFFF)
1615 : r.rlim_cur = 0x7FFFFFFF;
1616 : if (r.rlim_max > 0x7FFFFFFF)
1617 : r.rlim_max = 0x7FFFFFFF;
1618 :
1619 : if (put_user(r.rlim_cur, &rlim->rlim_cur) ||
1620 : put_user(r.rlim_max, &rlim->rlim_max))
1621 : return -EFAULT;
1622 : return 0;
1623 : }
1624 : #endif
1625 :
1626 : #endif
1627 :
1628 : static inline bool rlim64_is_infinity(__u64 rlim64)
1629 : {
1630 : #if BITS_PER_LONG < 64
1631 : return rlim64 >= ULONG_MAX;
1632 : #else
1633 : return rlim64 == RLIM64_INFINITY;
1634 : #endif
1635 : }
1636 :
1637 : static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64)
1638 : {
1639 0 : if (rlim->rlim_cur == RLIM_INFINITY)
1640 0 : rlim64->rlim_cur = RLIM64_INFINITY;
1641 : else
1642 0 : rlim64->rlim_cur = rlim->rlim_cur;
1643 0 : if (rlim->rlim_max == RLIM_INFINITY)
1644 0 : rlim64->rlim_max = RLIM64_INFINITY;
1645 : else
1646 0 : rlim64->rlim_max = rlim->rlim_max;
1647 : }
1648 :
1649 : static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim)
1650 : {
1651 0 : if (rlim64_is_infinity(rlim64->rlim_cur))
1652 0 : rlim->rlim_cur = RLIM_INFINITY;
1653 : else
1654 0 : rlim->rlim_cur = (unsigned long)rlim64->rlim_cur;
1655 0 : if (rlim64_is_infinity(rlim64->rlim_max))
1656 0 : rlim->rlim_max = RLIM_INFINITY;
1657 : else
1658 0 : rlim->rlim_max = (unsigned long)rlim64->rlim_max;
1659 : }
1660 :
1661 : /* rcu lock must be held */
1662 0 : static int check_prlimit_permission(struct task_struct *task,
1663 : unsigned int flags)
1664 : {
1665 0 : const struct cred *cred = current_cred(), *tcred;
1666 : bool id_match;
1667 :
1668 0 : if (current == task)
1669 : return 0;
1670 :
1671 0 : tcred = __task_cred(task);
1672 0 : id_match = (uid_eq(cred->uid, tcred->euid) &&
1673 0 : uid_eq(cred->uid, tcred->suid) &&
1674 0 : uid_eq(cred->uid, tcred->uid) &&
1675 0 : gid_eq(cred->gid, tcred->egid) &&
1676 0 : gid_eq(cred->gid, tcred->sgid) &&
1677 0 : gid_eq(cred->gid, tcred->gid));
1678 0 : if (!id_match && !ns_capable(tcred->user_ns, CAP_SYS_RESOURCE))
1679 : return -EPERM;
1680 :
1681 : return security_task_prlimit(cred, tcred, flags);
1682 : }
1683 :
1684 0 : SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource,
1685 : const struct rlimit64 __user *, new_rlim,
1686 : struct rlimit64 __user *, old_rlim)
1687 : {
1688 : struct rlimit64 old64, new64;
1689 : struct rlimit old, new;
1690 : struct task_struct *tsk;
1691 0 : unsigned int checkflags = 0;
1692 : int ret;
1693 :
1694 : if (old_rlim)
1695 : checkflags |= LSM_PRLIMIT_READ;
1696 :
1697 0 : if (new_rlim) {
1698 0 : if (copy_from_user(&new64, new_rlim, sizeof(new64)))
1699 : return -EFAULT;
1700 0 : rlim64_to_rlim(&new64, &new);
1701 0 : checkflags |= LSM_PRLIMIT_WRITE;
1702 : }
1703 :
1704 : rcu_read_lock();
1705 0 : tsk = pid ? find_task_by_vpid(pid) : current;
1706 0 : if (!tsk) {
1707 : rcu_read_unlock();
1708 0 : return -ESRCH;
1709 : }
1710 0 : ret = check_prlimit_permission(tsk, checkflags);
1711 0 : if (ret) {
1712 : rcu_read_unlock();
1713 0 : return ret;
1714 : }
1715 0 : get_task_struct(tsk);
1716 : rcu_read_unlock();
1717 :
1718 0 : ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL,
1719 : old_rlim ? &old : NULL);
1720 :
1721 0 : if (!ret && old_rlim) {
1722 0 : rlim_to_rlim64(&old, &old64);
1723 0 : if (copy_to_user(old_rlim, &old64, sizeof(old64)))
1724 0 : ret = -EFAULT;
1725 : }
1726 :
1727 0 : put_task_struct(tsk);
1728 0 : return ret;
1729 : }
1730 :
1731 0 : SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1732 : {
1733 : struct rlimit new_rlim;
1734 :
1735 0 : if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
1736 : return -EFAULT;
1737 0 : return do_prlimit(current, resource, &new_rlim, NULL);
1738 : }
1739 :
1740 : /*
1741 : * It would make sense to put struct rusage in the task_struct,
1742 : * except that would make the task_struct be *really big*. After
1743 : * task_struct gets moved into malloc'ed memory, it would
1744 : * make sense to do this. It will make moving the rest of the information
1745 : * a lot simpler! (Which we're not doing right now because we're not
1746 : * measuring them yet).
1747 : *
1748 : * When sampling multiple threads for RUSAGE_SELF, under SMP we might have
1749 : * races with threads incrementing their own counters. But since word
1750 : * reads are atomic, we either get new values or old values and we don't
1751 : * care which for the sums. We always take the siglock to protect reading
1752 : * the c* fields from p->signal from races with exit.c updating those
1753 : * fields when reaping, so a sample either gets all the additions of a
1754 : * given child after it's reaped, or none so this sample is before reaping.
1755 : *
1756 : * Locking:
1757 : * We need to take the siglock for CHILDEREN, SELF and BOTH
1758 : * for the cases current multithreaded, non-current single threaded
1759 : * non-current multithreaded. Thread traversal is now safe with
1760 : * the siglock held.
1761 : * Strictly speaking, we donot need to take the siglock if we are current and
1762 : * single threaded, as no one else can take our signal_struct away, no one
1763 : * else can reap the children to update signal->c* counters, and no one else
1764 : * can race with the signal-> fields. If we do not take any lock, the
1765 : * signal-> fields could be read out of order while another thread was just
1766 : * exiting. So we should place a read memory barrier when we avoid the lock.
1767 : * On the writer side, write memory barrier is implied in __exit_signal
1768 : * as __exit_signal releases the siglock spinlock after updating the signal->
1769 : * fields. But we don't do this yet to keep things simple.
1770 : *
1771 : */
1772 :
1773 : static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r)
1774 : {
1775 0 : r->ru_nvcsw += t->nvcsw;
1776 0 : r->ru_nivcsw += t->nivcsw;
1777 0 : r->ru_minflt += t->min_flt;
1778 0 : r->ru_majflt += t->maj_flt;
1779 0 : r->ru_inblock += task_io_get_inblock(t);
1780 0 : r->ru_oublock += task_io_get_oublock(t);
1781 : }
1782 :
1783 0 : void getrusage(struct task_struct *p, int who, struct rusage *r)
1784 : {
1785 : struct task_struct *t;
1786 : unsigned long flags;
1787 : u64 tgutime, tgstime, utime, stime;
1788 0 : unsigned long maxrss = 0;
1789 :
1790 0 : memset((char *)r, 0, sizeof (*r));
1791 0 : utime = stime = 0;
1792 :
1793 0 : if (who == RUSAGE_THREAD) {
1794 0 : task_cputime_adjusted(current, &utime, &stime);
1795 0 : accumulate_thread_rusage(p, r);
1796 0 : maxrss = p->signal->maxrss;
1797 0 : goto out;
1798 : }
1799 :
1800 0 : if (!lock_task_sighand(p, &flags))
1801 0 : return;
1802 :
1803 0 : switch (who) {
1804 : case RUSAGE_BOTH:
1805 : case RUSAGE_CHILDREN:
1806 0 : utime = p->signal->cutime;
1807 0 : stime = p->signal->cstime;
1808 0 : r->ru_nvcsw = p->signal->cnvcsw;
1809 0 : r->ru_nivcsw = p->signal->cnivcsw;
1810 0 : r->ru_minflt = p->signal->cmin_flt;
1811 0 : r->ru_majflt = p->signal->cmaj_flt;
1812 0 : r->ru_inblock = p->signal->cinblock;
1813 0 : r->ru_oublock = p->signal->coublock;
1814 0 : maxrss = p->signal->cmaxrss;
1815 :
1816 0 : if (who == RUSAGE_CHILDREN)
1817 : break;
1818 : fallthrough;
1819 :
1820 : case RUSAGE_SELF:
1821 0 : thread_group_cputime_adjusted(p, &tgutime, &tgstime);
1822 0 : utime += tgutime;
1823 0 : stime += tgstime;
1824 0 : r->ru_nvcsw += p->signal->nvcsw;
1825 0 : r->ru_nivcsw += p->signal->nivcsw;
1826 0 : r->ru_minflt += p->signal->min_flt;
1827 0 : r->ru_majflt += p->signal->maj_flt;
1828 0 : r->ru_inblock += p->signal->inblock;
1829 0 : r->ru_oublock += p->signal->oublock;
1830 0 : if (maxrss < p->signal->maxrss)
1831 0 : maxrss = p->signal->maxrss;
1832 0 : t = p;
1833 : do {
1834 0 : accumulate_thread_rusage(t, r);
1835 0 : } while_each_thread(p, t);
1836 : break;
1837 :
1838 : default:
1839 0 : BUG();
1840 : }
1841 0 : unlock_task_sighand(p, &flags);
1842 :
1843 : out:
1844 0 : r->ru_utime = ns_to_kernel_old_timeval(utime);
1845 0 : r->ru_stime = ns_to_kernel_old_timeval(stime);
1846 :
1847 0 : if (who != RUSAGE_CHILDREN) {
1848 0 : struct mm_struct *mm = get_task_mm(p);
1849 :
1850 0 : if (mm) {
1851 0 : setmax_mm_hiwater_rss(&maxrss, mm);
1852 0 : mmput(mm);
1853 : }
1854 : }
1855 0 : r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */
1856 : }
1857 :
1858 0 : SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru)
1859 : {
1860 : struct rusage r;
1861 :
1862 0 : if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1863 : who != RUSAGE_THREAD)
1864 : return -EINVAL;
1865 :
1866 0 : getrusage(current, who, &r);
1867 0 : return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
1868 : }
1869 :
1870 : #ifdef CONFIG_COMPAT
1871 : COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru)
1872 : {
1873 : struct rusage r;
1874 :
1875 : if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1876 : who != RUSAGE_THREAD)
1877 : return -EINVAL;
1878 :
1879 : getrusage(current, who, &r);
1880 : return put_compat_rusage(&r, ru);
1881 : }
1882 : #endif
1883 :
1884 0 : SYSCALL_DEFINE1(umask, int, mask)
1885 : {
1886 0 : mask = xchg(¤t->fs->umask, mask & S_IRWXUGO);
1887 0 : return mask;
1888 : }
1889 :
1890 0 : static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
1891 : {
1892 : struct fd exe;
1893 : struct inode *inode;
1894 : int err;
1895 :
1896 0 : exe = fdget(fd);
1897 0 : if (!exe.file)
1898 : return -EBADF;
1899 :
1900 0 : inode = file_inode(exe.file);
1901 :
1902 : /*
1903 : * Because the original mm->exe_file points to executable file, make
1904 : * sure that this one is executable as well, to avoid breaking an
1905 : * overall picture.
1906 : */
1907 0 : err = -EACCES;
1908 0 : if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path))
1909 : goto exit;
1910 :
1911 0 : err = file_permission(exe.file, MAY_EXEC);
1912 0 : if (err)
1913 : goto exit;
1914 :
1915 0 : err = replace_mm_exe_file(mm, exe.file);
1916 : exit:
1917 0 : fdput(exe);
1918 : return err;
1919 : }
1920 :
1921 : /*
1922 : * Check arithmetic relations of passed addresses.
1923 : *
1924 : * WARNING: we don't require any capability here so be very careful
1925 : * in what is allowed for modification from userspace.
1926 : */
1927 0 : static int validate_prctl_map_addr(struct prctl_mm_map *prctl_map)
1928 : {
1929 0 : unsigned long mmap_max_addr = TASK_SIZE;
1930 0 : int error = -EINVAL, i;
1931 :
1932 : static const unsigned char offsets[] = {
1933 : offsetof(struct prctl_mm_map, start_code),
1934 : offsetof(struct prctl_mm_map, end_code),
1935 : offsetof(struct prctl_mm_map, start_data),
1936 : offsetof(struct prctl_mm_map, end_data),
1937 : offsetof(struct prctl_mm_map, start_brk),
1938 : offsetof(struct prctl_mm_map, brk),
1939 : offsetof(struct prctl_mm_map, start_stack),
1940 : offsetof(struct prctl_mm_map, arg_start),
1941 : offsetof(struct prctl_mm_map, arg_end),
1942 : offsetof(struct prctl_mm_map, env_start),
1943 : offsetof(struct prctl_mm_map, env_end),
1944 : };
1945 :
1946 : /*
1947 : * Make sure the members are not somewhere outside
1948 : * of allowed address space.
1949 : */
1950 0 : for (i = 0; i < ARRAY_SIZE(offsets); i++) {
1951 0 : u64 val = *(u64 *)((char *)prctl_map + offsets[i]);
1952 :
1953 0 : if ((unsigned long)val >= mmap_max_addr ||
1954 0 : (unsigned long)val < mmap_min_addr)
1955 : goto out;
1956 : }
1957 :
1958 : /*
1959 : * Make sure the pairs are ordered.
1960 : */
1961 : #define __prctl_check_order(__m1, __op, __m2) \
1962 : ((unsigned long)prctl_map->__m1 __op \
1963 : (unsigned long)prctl_map->__m2) ? 0 : -EINVAL
1964 0 : error = __prctl_check_order(start_code, <, end_code);
1965 0 : error |= __prctl_check_order(start_data,<=, end_data);
1966 0 : error |= __prctl_check_order(start_brk, <=, brk);
1967 0 : error |= __prctl_check_order(arg_start, <=, arg_end);
1968 0 : error |= __prctl_check_order(env_start, <=, env_end);
1969 0 : if (error)
1970 : goto out;
1971 : #undef __prctl_check_order
1972 :
1973 0 : error = -EINVAL;
1974 :
1975 : /*
1976 : * Neither we should allow to override limits if they set.
1977 : */
1978 0 : if (check_data_rlimit(rlimit(RLIMIT_DATA), prctl_map->brk,
1979 : prctl_map->start_brk, prctl_map->end_data,
1980 : prctl_map->start_data))
1981 : goto out;
1982 :
1983 0 : error = 0;
1984 : out:
1985 0 : return error;
1986 : }
1987 :
1988 : #ifdef CONFIG_CHECKPOINT_RESTORE
1989 : static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size)
1990 : {
1991 : struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, };
1992 : unsigned long user_auxv[AT_VECTOR_SIZE];
1993 : struct mm_struct *mm = current->mm;
1994 : int error;
1995 :
1996 : BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
1997 : BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256);
1998 :
1999 : if (opt == PR_SET_MM_MAP_SIZE)
2000 : return put_user((unsigned int)sizeof(prctl_map),
2001 : (unsigned int __user *)addr);
2002 :
2003 : if (data_size != sizeof(prctl_map))
2004 : return -EINVAL;
2005 :
2006 : if (copy_from_user(&prctl_map, addr, sizeof(prctl_map)))
2007 : return -EFAULT;
2008 :
2009 : error = validate_prctl_map_addr(&prctl_map);
2010 : if (error)
2011 : return error;
2012 :
2013 : if (prctl_map.auxv_size) {
2014 : /*
2015 : * Someone is trying to cheat the auxv vector.
2016 : */
2017 : if (!prctl_map.auxv ||
2018 : prctl_map.auxv_size > sizeof(mm->saved_auxv))
2019 : return -EINVAL;
2020 :
2021 : memset(user_auxv, 0, sizeof(user_auxv));
2022 : if (copy_from_user(user_auxv,
2023 : (const void __user *)prctl_map.auxv,
2024 : prctl_map.auxv_size))
2025 : return -EFAULT;
2026 :
2027 : /* Last entry must be AT_NULL as specification requires */
2028 : user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL;
2029 : user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL;
2030 : }
2031 :
2032 : if (prctl_map.exe_fd != (u32)-1) {
2033 : /*
2034 : * Check if the current user is checkpoint/restore capable.
2035 : * At the time of this writing, it checks for CAP_SYS_ADMIN
2036 : * or CAP_CHECKPOINT_RESTORE.
2037 : * Note that a user with access to ptrace can masquerade an
2038 : * arbitrary program as any executable, even setuid ones.
2039 : * This may have implications in the tomoyo subsystem.
2040 : */
2041 : if (!checkpoint_restore_ns_capable(current_user_ns()))
2042 : return -EPERM;
2043 :
2044 : error = prctl_set_mm_exe_file(mm, prctl_map.exe_fd);
2045 : if (error)
2046 : return error;
2047 : }
2048 :
2049 : /*
2050 : * arg_lock protects concurrent updates but we still need mmap_lock for
2051 : * read to exclude races with sys_brk.
2052 : */
2053 : mmap_read_lock(mm);
2054 :
2055 : /*
2056 : * We don't validate if these members are pointing to
2057 : * real present VMAs because application may have correspond
2058 : * VMAs already unmapped and kernel uses these members for statistics
2059 : * output in procfs mostly, except
2060 : *
2061 : * - @start_brk/@brk which are used in do_brk_flags but kernel lookups
2062 : * for VMAs when updating these members so anything wrong written
2063 : * here cause kernel to swear at userspace program but won't lead
2064 : * to any problem in kernel itself
2065 : */
2066 :
2067 : spin_lock(&mm->arg_lock);
2068 : mm->start_code = prctl_map.start_code;
2069 : mm->end_code = prctl_map.end_code;
2070 : mm->start_data = prctl_map.start_data;
2071 : mm->end_data = prctl_map.end_data;
2072 : mm->start_brk = prctl_map.start_brk;
2073 : mm->brk = prctl_map.brk;
2074 : mm->start_stack = prctl_map.start_stack;
2075 : mm->arg_start = prctl_map.arg_start;
2076 : mm->arg_end = prctl_map.arg_end;
2077 : mm->env_start = prctl_map.env_start;
2078 : mm->env_end = prctl_map.env_end;
2079 : spin_unlock(&mm->arg_lock);
2080 :
2081 : /*
2082 : * Note this update of @saved_auxv is lockless thus
2083 : * if someone reads this member in procfs while we're
2084 : * updating -- it may get partly updated results. It's
2085 : * known and acceptable trade off: we leave it as is to
2086 : * not introduce additional locks here making the kernel
2087 : * more complex.
2088 : */
2089 : if (prctl_map.auxv_size)
2090 : memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv));
2091 :
2092 : mmap_read_unlock(mm);
2093 : return 0;
2094 : }
2095 : #endif /* CONFIG_CHECKPOINT_RESTORE */
2096 :
2097 0 : static int prctl_set_auxv(struct mm_struct *mm, unsigned long addr,
2098 : unsigned long len)
2099 : {
2100 : /*
2101 : * This doesn't move the auxiliary vector itself since it's pinned to
2102 : * mm_struct, but it permits filling the vector with new values. It's
2103 : * up to the caller to provide sane values here, otherwise userspace
2104 : * tools which use this vector might be unhappy.
2105 : */
2106 0 : unsigned long user_auxv[AT_VECTOR_SIZE] = {};
2107 :
2108 0 : if (len > sizeof(user_auxv))
2109 : return -EINVAL;
2110 :
2111 0 : if (copy_from_user(user_auxv, (const void __user *)addr, len))
2112 : return -EFAULT;
2113 :
2114 : /* Make sure the last entry is always AT_NULL */
2115 0 : user_auxv[AT_VECTOR_SIZE - 2] = 0;
2116 0 : user_auxv[AT_VECTOR_SIZE - 1] = 0;
2117 :
2118 : BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
2119 :
2120 0 : task_lock(current);
2121 0 : memcpy(mm->saved_auxv, user_auxv, len);
2122 0 : task_unlock(current);
2123 :
2124 0 : return 0;
2125 : }
2126 :
2127 0 : static int prctl_set_mm(int opt, unsigned long addr,
2128 : unsigned long arg4, unsigned long arg5)
2129 : {
2130 0 : struct mm_struct *mm = current->mm;
2131 0 : struct prctl_mm_map prctl_map = {
2132 : .auxv = NULL,
2133 : .auxv_size = 0,
2134 : .exe_fd = -1,
2135 : };
2136 : struct vm_area_struct *vma;
2137 : int error;
2138 :
2139 0 : if (arg5 || (arg4 && (opt != PR_SET_MM_AUXV &&
2140 0 : opt != PR_SET_MM_MAP &&
2141 : opt != PR_SET_MM_MAP_SIZE)))
2142 : return -EINVAL;
2143 :
2144 : #ifdef CONFIG_CHECKPOINT_RESTORE
2145 : if (opt == PR_SET_MM_MAP || opt == PR_SET_MM_MAP_SIZE)
2146 : return prctl_set_mm_map(opt, (const void __user *)addr, arg4);
2147 : #endif
2148 :
2149 0 : if (!capable(CAP_SYS_RESOURCE))
2150 : return -EPERM;
2151 :
2152 0 : if (opt == PR_SET_MM_EXE_FILE)
2153 0 : return prctl_set_mm_exe_file(mm, (unsigned int)addr);
2154 :
2155 0 : if (opt == PR_SET_MM_AUXV)
2156 0 : return prctl_set_auxv(mm, addr, arg4);
2157 :
2158 0 : if (addr >= TASK_SIZE || addr < mmap_min_addr)
2159 : return -EINVAL;
2160 :
2161 0 : error = -EINVAL;
2162 :
2163 : /*
2164 : * arg_lock protects concurrent updates of arg boundaries, we need
2165 : * mmap_lock for a) concurrent sys_brk, b) finding VMA for addr
2166 : * validation.
2167 : */
2168 0 : mmap_read_lock(mm);
2169 0 : vma = find_vma(mm, addr);
2170 :
2171 0 : spin_lock(&mm->arg_lock);
2172 0 : prctl_map.start_code = mm->start_code;
2173 0 : prctl_map.end_code = mm->end_code;
2174 0 : prctl_map.start_data = mm->start_data;
2175 0 : prctl_map.end_data = mm->end_data;
2176 0 : prctl_map.start_brk = mm->start_brk;
2177 0 : prctl_map.brk = mm->brk;
2178 0 : prctl_map.start_stack = mm->start_stack;
2179 0 : prctl_map.arg_start = mm->arg_start;
2180 0 : prctl_map.arg_end = mm->arg_end;
2181 0 : prctl_map.env_start = mm->env_start;
2182 0 : prctl_map.env_end = mm->env_end;
2183 :
2184 0 : switch (opt) {
2185 : case PR_SET_MM_START_CODE:
2186 0 : prctl_map.start_code = addr;
2187 0 : break;
2188 : case PR_SET_MM_END_CODE:
2189 0 : prctl_map.end_code = addr;
2190 0 : break;
2191 : case PR_SET_MM_START_DATA:
2192 0 : prctl_map.start_data = addr;
2193 0 : break;
2194 : case PR_SET_MM_END_DATA:
2195 0 : prctl_map.end_data = addr;
2196 0 : break;
2197 : case PR_SET_MM_START_STACK:
2198 0 : prctl_map.start_stack = addr;
2199 0 : break;
2200 : case PR_SET_MM_START_BRK:
2201 0 : prctl_map.start_brk = addr;
2202 0 : break;
2203 : case PR_SET_MM_BRK:
2204 0 : prctl_map.brk = addr;
2205 0 : break;
2206 : case PR_SET_MM_ARG_START:
2207 0 : prctl_map.arg_start = addr;
2208 0 : break;
2209 : case PR_SET_MM_ARG_END:
2210 0 : prctl_map.arg_end = addr;
2211 0 : break;
2212 : case PR_SET_MM_ENV_START:
2213 0 : prctl_map.env_start = addr;
2214 0 : break;
2215 : case PR_SET_MM_ENV_END:
2216 0 : prctl_map.env_end = addr;
2217 0 : break;
2218 : default:
2219 : goto out;
2220 : }
2221 :
2222 0 : error = validate_prctl_map_addr(&prctl_map);
2223 0 : if (error)
2224 : goto out;
2225 :
2226 : switch (opt) {
2227 : /*
2228 : * If command line arguments and environment
2229 : * are placed somewhere else on stack, we can
2230 : * set them up here, ARG_START/END to setup
2231 : * command line arguments and ENV_START/END
2232 : * for environment.
2233 : */
2234 : case PR_SET_MM_START_STACK:
2235 : case PR_SET_MM_ARG_START:
2236 : case PR_SET_MM_ARG_END:
2237 : case PR_SET_MM_ENV_START:
2238 : case PR_SET_MM_ENV_END:
2239 0 : if (!vma) {
2240 : error = -EFAULT;
2241 : goto out;
2242 : }
2243 : }
2244 :
2245 0 : mm->start_code = prctl_map.start_code;
2246 0 : mm->end_code = prctl_map.end_code;
2247 0 : mm->start_data = prctl_map.start_data;
2248 0 : mm->end_data = prctl_map.end_data;
2249 0 : mm->start_brk = prctl_map.start_brk;
2250 0 : mm->brk = prctl_map.brk;
2251 0 : mm->start_stack = prctl_map.start_stack;
2252 0 : mm->arg_start = prctl_map.arg_start;
2253 0 : mm->arg_end = prctl_map.arg_end;
2254 0 : mm->env_start = prctl_map.env_start;
2255 0 : mm->env_end = prctl_map.env_end;
2256 :
2257 0 : error = 0;
2258 : out:
2259 0 : spin_unlock(&mm->arg_lock);
2260 0 : mmap_read_unlock(mm);
2261 0 : return error;
2262 : }
2263 :
2264 : #ifdef CONFIG_CHECKPOINT_RESTORE
2265 : static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr)
2266 : {
2267 : return put_user(me->clear_child_tid, tid_addr);
2268 : }
2269 : #else
2270 : static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr)
2271 : {
2272 : return -EINVAL;
2273 : }
2274 : #endif
2275 :
2276 0 : static int propagate_has_child_subreaper(struct task_struct *p, void *data)
2277 : {
2278 : /*
2279 : * If task has has_child_subreaper - all its descendants
2280 : * already have these flag too and new descendants will
2281 : * inherit it on fork, skip them.
2282 : *
2283 : * If we've found child_reaper - skip descendants in
2284 : * it's subtree as they will never get out pidns.
2285 : */
2286 0 : if (p->signal->has_child_subreaper ||
2287 0 : is_child_reaper(task_pid(p)))
2288 : return 0;
2289 :
2290 0 : p->signal->has_child_subreaper = 1;
2291 0 : return 1;
2292 : }
2293 :
2294 0 : int __weak arch_prctl_spec_ctrl_get(struct task_struct *t, unsigned long which)
2295 : {
2296 0 : return -EINVAL;
2297 : }
2298 :
2299 0 : int __weak arch_prctl_spec_ctrl_set(struct task_struct *t, unsigned long which,
2300 : unsigned long ctrl)
2301 : {
2302 0 : return -EINVAL;
2303 : }
2304 :
2305 : #define PR_IO_FLUSHER (PF_MEMALLOC_NOIO | PF_LOCAL_THROTTLE)
2306 :
2307 : #ifdef CONFIG_ANON_VMA_NAME
2308 :
2309 : #define ANON_VMA_NAME_MAX_LEN 80
2310 : #define ANON_VMA_NAME_INVALID_CHARS "\\`$[]"
2311 :
2312 : static inline bool is_valid_name_char(char ch)
2313 : {
2314 : /* printable ascii characters, excluding ANON_VMA_NAME_INVALID_CHARS */
2315 : return ch > 0x1f && ch < 0x7f &&
2316 : !strchr(ANON_VMA_NAME_INVALID_CHARS, ch);
2317 : }
2318 :
2319 : static int prctl_set_vma(unsigned long opt, unsigned long addr,
2320 : unsigned long size, unsigned long arg)
2321 : {
2322 : struct mm_struct *mm = current->mm;
2323 : const char __user *uname;
2324 : struct anon_vma_name *anon_name = NULL;
2325 : int error;
2326 :
2327 : switch (opt) {
2328 : case PR_SET_VMA_ANON_NAME:
2329 : uname = (const char __user *)arg;
2330 : if (uname) {
2331 : char *name, *pch;
2332 :
2333 : name = strndup_user(uname, ANON_VMA_NAME_MAX_LEN);
2334 : if (IS_ERR(name))
2335 : return PTR_ERR(name);
2336 :
2337 : for (pch = name; *pch != '\0'; pch++) {
2338 : if (!is_valid_name_char(*pch)) {
2339 : kfree(name);
2340 : return -EINVAL;
2341 : }
2342 : }
2343 : /* anon_vma has its own copy */
2344 : anon_name = anon_vma_name_alloc(name);
2345 : kfree(name);
2346 : if (!anon_name)
2347 : return -ENOMEM;
2348 :
2349 : }
2350 :
2351 : mmap_write_lock(mm);
2352 : error = madvise_set_anon_name(mm, addr, size, anon_name);
2353 : mmap_write_unlock(mm);
2354 : anon_vma_name_put(anon_name);
2355 : break;
2356 : default:
2357 : error = -EINVAL;
2358 : }
2359 :
2360 : return error;
2361 : }
2362 :
2363 : #else /* CONFIG_ANON_VMA_NAME */
2364 : static int prctl_set_vma(unsigned long opt, unsigned long start,
2365 : unsigned long size, unsigned long arg)
2366 : {
2367 : return -EINVAL;
2368 : }
2369 : #endif /* CONFIG_ANON_VMA_NAME */
2370 :
2371 0 : static inline int prctl_set_mdwe(unsigned long bits, unsigned long arg3,
2372 : unsigned long arg4, unsigned long arg5)
2373 : {
2374 0 : if (arg3 || arg4 || arg5)
2375 : return -EINVAL;
2376 :
2377 0 : if (bits & ~(PR_MDWE_REFUSE_EXEC_GAIN))
2378 : return -EINVAL;
2379 :
2380 0 : if (bits & PR_MDWE_REFUSE_EXEC_GAIN)
2381 0 : set_bit(MMF_HAS_MDWE, ¤t->mm->flags);
2382 0 : else if (test_bit(MMF_HAS_MDWE, ¤t->mm->flags))
2383 : return -EPERM; /* Cannot unset the flag */
2384 :
2385 : return 0;
2386 : }
2387 :
2388 : static inline int prctl_get_mdwe(unsigned long arg2, unsigned long arg3,
2389 : unsigned long arg4, unsigned long arg5)
2390 : {
2391 0 : if (arg2 || arg3 || arg4 || arg5)
2392 : return -EINVAL;
2393 :
2394 0 : return test_bit(MMF_HAS_MDWE, ¤t->mm->flags) ?
2395 0 : PR_MDWE_REFUSE_EXEC_GAIN : 0;
2396 : }
2397 :
2398 0 : static int prctl_get_auxv(void __user *addr, unsigned long len)
2399 : {
2400 0 : struct mm_struct *mm = current->mm;
2401 0 : unsigned long size = min_t(unsigned long, sizeof(mm->saved_auxv), len);
2402 :
2403 0 : if (size && copy_to_user(addr, mm->saved_auxv, size))
2404 : return -EFAULT;
2405 : return sizeof(mm->saved_auxv);
2406 : }
2407 :
2408 0 : SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
2409 : unsigned long, arg4, unsigned long, arg5)
2410 : {
2411 0 : struct task_struct *me = current;
2412 : unsigned char comm[sizeof(me->comm)];
2413 : long error;
2414 :
2415 0 : error = security_task_prctl(option, arg2, arg3, arg4, arg5);
2416 0 : if (error != -ENOSYS)
2417 : return error;
2418 :
2419 0 : error = 0;
2420 0 : switch (option) {
2421 : case PR_SET_PDEATHSIG:
2422 0 : if (!valid_signal(arg2)) {
2423 : error = -EINVAL;
2424 : break;
2425 : }
2426 0 : me->pdeath_signal = arg2;
2427 0 : break;
2428 : case PR_GET_PDEATHSIG:
2429 0 : error = put_user(me->pdeath_signal, (int __user *)arg2);
2430 0 : break;
2431 : case PR_GET_DUMPABLE:
2432 0 : error = get_dumpable(me->mm);
2433 0 : break;
2434 : case PR_SET_DUMPABLE:
2435 0 : if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) {
2436 : error = -EINVAL;
2437 : break;
2438 : }
2439 0 : set_dumpable(me->mm, arg2);
2440 0 : break;
2441 :
2442 : case PR_SET_UNALIGN:
2443 : error = SET_UNALIGN_CTL(me, arg2);
2444 : break;
2445 : case PR_GET_UNALIGN:
2446 : error = GET_UNALIGN_CTL(me, arg2);
2447 : break;
2448 : case PR_SET_FPEMU:
2449 : error = SET_FPEMU_CTL(me, arg2);
2450 : break;
2451 : case PR_GET_FPEMU:
2452 : error = GET_FPEMU_CTL(me, arg2);
2453 : break;
2454 : case PR_SET_FPEXC:
2455 : error = SET_FPEXC_CTL(me, arg2);
2456 : break;
2457 : case PR_GET_FPEXC:
2458 : error = GET_FPEXC_CTL(me, arg2);
2459 : break;
2460 : case PR_GET_TIMING:
2461 0 : error = PR_TIMING_STATISTICAL;
2462 0 : break;
2463 : case PR_SET_TIMING:
2464 0 : if (arg2 != PR_TIMING_STATISTICAL)
2465 0 : error = -EINVAL;
2466 : break;
2467 : case PR_SET_NAME:
2468 0 : comm[sizeof(me->comm) - 1] = 0;
2469 0 : if (strncpy_from_user(comm, (char __user *)arg2,
2470 : sizeof(me->comm) - 1) < 0)
2471 : return -EFAULT;
2472 : set_task_comm(me, comm);
2473 : proc_comm_connector(me);
2474 : break;
2475 : case PR_GET_NAME:
2476 0 : get_task_comm(comm, me);
2477 0 : if (copy_to_user((char __user *)arg2, comm, sizeof(comm)))
2478 : return -EFAULT;
2479 : break;
2480 : case PR_GET_ENDIAN:
2481 : error = GET_ENDIAN(me, arg2);
2482 : break;
2483 : case PR_SET_ENDIAN:
2484 : error = SET_ENDIAN(me, arg2);
2485 : break;
2486 : case PR_GET_SECCOMP:
2487 0 : error = prctl_get_seccomp();
2488 0 : break;
2489 : case PR_SET_SECCOMP:
2490 0 : error = prctl_set_seccomp(arg2, (char __user *)arg3);
2491 0 : break;
2492 : case PR_GET_TSC:
2493 : error = GET_TSC_CTL(arg2);
2494 : break;
2495 : case PR_SET_TSC:
2496 : error = SET_TSC_CTL(arg2);
2497 : break;
2498 : case PR_TASK_PERF_EVENTS_DISABLE:
2499 : error = perf_event_task_disable();
2500 : break;
2501 : case PR_TASK_PERF_EVENTS_ENABLE:
2502 : error = perf_event_task_enable();
2503 : break;
2504 : case PR_GET_TIMERSLACK:
2505 0 : if (current->timer_slack_ns > ULONG_MAX)
2506 : error = ULONG_MAX;
2507 : else
2508 0 : error = current->timer_slack_ns;
2509 : break;
2510 : case PR_SET_TIMERSLACK:
2511 0 : if (arg2 <= 0)
2512 0 : current->timer_slack_ns =
2513 0 : current->default_timer_slack_ns;
2514 : else
2515 0 : current->timer_slack_ns = arg2;
2516 : break;
2517 : case PR_MCE_KILL:
2518 0 : if (arg4 | arg5)
2519 : return -EINVAL;
2520 0 : switch (arg2) {
2521 : case PR_MCE_KILL_CLEAR:
2522 0 : if (arg3 != 0)
2523 : return -EINVAL;
2524 0 : current->flags &= ~PF_MCE_PROCESS;
2525 0 : break;
2526 : case PR_MCE_KILL_SET:
2527 0 : current->flags |= PF_MCE_PROCESS;
2528 0 : if (arg3 == PR_MCE_KILL_EARLY)
2529 0 : current->flags |= PF_MCE_EARLY;
2530 0 : else if (arg3 == PR_MCE_KILL_LATE)
2531 0 : current->flags &= ~PF_MCE_EARLY;
2532 0 : else if (arg3 == PR_MCE_KILL_DEFAULT)
2533 0 : current->flags &=
2534 : ~(PF_MCE_EARLY|PF_MCE_PROCESS);
2535 : else
2536 : return -EINVAL;
2537 : break;
2538 : case PR_GET_AUXV:
2539 : if (arg4 || arg5)
2540 : return -EINVAL;
2541 0 : error = prctl_get_auxv((void __user *)arg2, arg3);
2542 0 : break;
2543 : default:
2544 : return -EINVAL;
2545 : }
2546 : break;
2547 : case PR_MCE_KILL_GET:
2548 0 : if (arg2 | arg3 | arg4 | arg5)
2549 : return -EINVAL;
2550 0 : if (current->flags & PF_MCE_PROCESS)
2551 0 : error = (current->flags & PF_MCE_EARLY) ?
2552 0 : PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE;
2553 : else
2554 : error = PR_MCE_KILL_DEFAULT;
2555 : break;
2556 : case PR_SET_MM:
2557 0 : error = prctl_set_mm(arg2, arg3, arg4, arg5);
2558 0 : break;
2559 : case PR_GET_TID_ADDRESS:
2560 : error = prctl_get_tid_address(me, (int __user * __user *)arg2);
2561 : break;
2562 : case PR_SET_CHILD_SUBREAPER:
2563 0 : me->signal->is_child_subreaper = !!arg2;
2564 0 : if (!arg2)
2565 : break;
2566 :
2567 0 : walk_process_tree(me, propagate_has_child_subreaper, NULL);
2568 0 : break;
2569 : case PR_GET_CHILD_SUBREAPER:
2570 0 : error = put_user(me->signal->is_child_subreaper,
2571 : (int __user *)arg2);
2572 0 : break;
2573 : case PR_SET_NO_NEW_PRIVS:
2574 0 : if (arg2 != 1 || arg3 || arg4 || arg5)
2575 : return -EINVAL;
2576 :
2577 0 : task_set_no_new_privs(current);
2578 : break;
2579 : case PR_GET_NO_NEW_PRIVS:
2580 0 : if (arg2 || arg3 || arg4 || arg5)
2581 : return -EINVAL;
2582 0 : return task_no_new_privs(current) ? 1 : 0;
2583 : case PR_GET_THP_DISABLE:
2584 0 : if (arg2 || arg3 || arg4 || arg5)
2585 : return -EINVAL;
2586 0 : error = !!test_bit(MMF_DISABLE_THP, &me->mm->flags);
2587 : break;
2588 : case PR_SET_THP_DISABLE:
2589 0 : if (arg3 || arg4 || arg5)
2590 : return -EINVAL;
2591 0 : if (mmap_write_lock_killable(me->mm))
2592 : return -EINTR;
2593 0 : if (arg2)
2594 0 : set_bit(MMF_DISABLE_THP, &me->mm->flags);
2595 : else
2596 0 : clear_bit(MMF_DISABLE_THP, &me->mm->flags);
2597 0 : mmap_write_unlock(me->mm);
2598 : break;
2599 : case PR_MPX_ENABLE_MANAGEMENT:
2600 : case PR_MPX_DISABLE_MANAGEMENT:
2601 : /* No longer implemented: */
2602 : return -EINVAL;
2603 : case PR_SET_FP_MODE:
2604 : error = SET_FP_MODE(me, arg2);
2605 : break;
2606 : case PR_GET_FP_MODE:
2607 : error = GET_FP_MODE(me);
2608 : break;
2609 : case PR_SVE_SET_VL:
2610 : error = SVE_SET_VL(arg2);
2611 : break;
2612 : case PR_SVE_GET_VL:
2613 : error = SVE_GET_VL();
2614 : break;
2615 : case PR_SME_SET_VL:
2616 : error = SME_SET_VL(arg2);
2617 : break;
2618 : case PR_SME_GET_VL:
2619 : error = SME_GET_VL();
2620 : break;
2621 : case PR_GET_SPECULATION_CTRL:
2622 0 : if (arg3 || arg4 || arg5)
2623 : return -EINVAL;
2624 0 : error = arch_prctl_spec_ctrl_get(me, arg2);
2625 0 : break;
2626 : case PR_SET_SPECULATION_CTRL:
2627 0 : if (arg4 || arg5)
2628 : return -EINVAL;
2629 0 : error = arch_prctl_spec_ctrl_set(me, arg2, arg3);
2630 0 : break;
2631 : case PR_PAC_RESET_KEYS:
2632 0 : if (arg3 || arg4 || arg5)
2633 : return -EINVAL;
2634 : error = PAC_RESET_KEYS(me, arg2);
2635 : break;
2636 : case PR_PAC_SET_ENABLED_KEYS:
2637 0 : if (arg4 || arg5)
2638 : return -EINVAL;
2639 : error = PAC_SET_ENABLED_KEYS(me, arg2, arg3);
2640 : break;
2641 : case PR_PAC_GET_ENABLED_KEYS:
2642 0 : if (arg2 || arg3 || arg4 || arg5)
2643 : return -EINVAL;
2644 : error = PAC_GET_ENABLED_KEYS(me);
2645 : break;
2646 : case PR_SET_TAGGED_ADDR_CTRL:
2647 0 : if (arg3 || arg4 || arg5)
2648 : return -EINVAL;
2649 : error = SET_TAGGED_ADDR_CTRL(arg2);
2650 : break;
2651 : case PR_GET_TAGGED_ADDR_CTRL:
2652 0 : if (arg2 || arg3 || arg4 || arg5)
2653 : return -EINVAL;
2654 : error = GET_TAGGED_ADDR_CTRL();
2655 : break;
2656 : case PR_SET_IO_FLUSHER:
2657 0 : if (!capable(CAP_SYS_RESOURCE))
2658 : return -EPERM;
2659 :
2660 0 : if (arg3 || arg4 || arg5)
2661 : return -EINVAL;
2662 :
2663 0 : if (arg2 == 1)
2664 0 : current->flags |= PR_IO_FLUSHER;
2665 0 : else if (!arg2)
2666 0 : current->flags &= ~PR_IO_FLUSHER;
2667 : else
2668 : return -EINVAL;
2669 : break;
2670 : case PR_GET_IO_FLUSHER:
2671 0 : if (!capable(CAP_SYS_RESOURCE))
2672 : return -EPERM;
2673 :
2674 0 : if (arg2 || arg3 || arg4 || arg5)
2675 : return -EINVAL;
2676 :
2677 0 : error = (current->flags & PR_IO_FLUSHER) == PR_IO_FLUSHER;
2678 0 : break;
2679 : case PR_SET_SYSCALL_USER_DISPATCH:
2680 : error = set_syscall_user_dispatch(arg2, arg3, arg4,
2681 : (char __user *) arg5);
2682 : break;
2683 : #ifdef CONFIG_SCHED_CORE
2684 : case PR_SCHED_CORE:
2685 : error = sched_core_share_pid(arg2, arg3, arg4, arg5);
2686 : break;
2687 : #endif
2688 : case PR_SET_MDWE:
2689 0 : error = prctl_set_mdwe(arg2, arg3, arg4, arg5);
2690 0 : break;
2691 : case PR_GET_MDWE:
2692 0 : error = prctl_get_mdwe(arg2, arg3, arg4, arg5);
2693 0 : break;
2694 : case PR_SET_VMA:
2695 : error = prctl_set_vma(arg2, arg3, arg4, arg5);
2696 : break;
2697 : #ifdef CONFIG_KSM
2698 : case PR_SET_MEMORY_MERGE:
2699 : if (arg3 || arg4 || arg5)
2700 : return -EINVAL;
2701 : if (mmap_write_lock_killable(me->mm))
2702 : return -EINTR;
2703 :
2704 : if (arg2)
2705 : error = ksm_enable_merge_any(me->mm);
2706 : else
2707 : error = ksm_disable_merge_any(me->mm);
2708 : mmap_write_unlock(me->mm);
2709 : break;
2710 : case PR_GET_MEMORY_MERGE:
2711 : if (arg2 || arg3 || arg4 || arg5)
2712 : return -EINVAL;
2713 :
2714 : error = !!test_bit(MMF_VM_MERGE_ANY, &me->mm->flags);
2715 : break;
2716 : #endif
2717 : case PR_RISCV_V_SET_CONTROL:
2718 : error = RISCV_V_SET_CONTROL(arg2);
2719 : break;
2720 : case PR_RISCV_V_GET_CONTROL:
2721 : error = RISCV_V_GET_CONTROL();
2722 : break;
2723 : default:
2724 : error = -EINVAL;
2725 : break;
2726 : }
2727 : return error;
2728 : }
2729 :
2730 0 : SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
2731 : struct getcpu_cache __user *, unused)
2732 : {
2733 0 : int err = 0;
2734 0 : int cpu = raw_smp_processor_id();
2735 :
2736 0 : if (cpup)
2737 0 : err |= put_user(cpu, cpup);
2738 0 : if (nodep)
2739 0 : err |= put_user(cpu_to_node(cpu), nodep);
2740 0 : return err ? -EFAULT : 0;
2741 : }
2742 :
2743 : /**
2744 : * do_sysinfo - fill in sysinfo struct
2745 : * @info: pointer to buffer to fill
2746 : */
2747 0 : static int do_sysinfo(struct sysinfo *info)
2748 : {
2749 : unsigned long mem_total, sav_total;
2750 : unsigned int mem_unit, bitcount;
2751 : struct timespec64 tp;
2752 :
2753 0 : memset(info, 0, sizeof(struct sysinfo));
2754 :
2755 0 : ktime_get_boottime_ts64(&tp);
2756 0 : timens_add_boottime(&tp);
2757 0 : info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0);
2758 :
2759 0 : get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT);
2760 :
2761 0 : info->procs = nr_threads;
2762 :
2763 0 : si_meminfo(info);
2764 0 : si_swapinfo(info);
2765 :
2766 : /*
2767 : * If the sum of all the available memory (i.e. ram + swap)
2768 : * is less than can be stored in a 32 bit unsigned long then
2769 : * we can be binary compatible with 2.2.x kernels. If not,
2770 : * well, in that case 2.2.x was broken anyways...
2771 : *
2772 : * -Erik Andersen <andersee@debian.org>
2773 : */
2774 :
2775 0 : mem_total = info->totalram + info->totalswap;
2776 0 : if (mem_total < info->totalram || mem_total < info->totalswap)
2777 : goto out;
2778 0 : bitcount = 0;
2779 0 : mem_unit = info->mem_unit;
2780 0 : while (mem_unit > 1) {
2781 0 : bitcount++;
2782 0 : mem_unit >>= 1;
2783 0 : sav_total = mem_total;
2784 0 : mem_total <<= 1;
2785 0 : if (mem_total < sav_total)
2786 : goto out;
2787 : }
2788 :
2789 : /*
2790 : * If mem_total did not overflow, multiply all memory values by
2791 : * info->mem_unit and set it to 1. This leaves things compatible
2792 : * with 2.2.x, and also retains compatibility with earlier 2.4.x
2793 : * kernels...
2794 : */
2795 :
2796 0 : info->mem_unit = 1;
2797 0 : info->totalram <<= bitcount;
2798 0 : info->freeram <<= bitcount;
2799 0 : info->sharedram <<= bitcount;
2800 0 : info->bufferram <<= bitcount;
2801 0 : info->totalswap <<= bitcount;
2802 0 : info->freeswap <<= bitcount;
2803 0 : info->totalhigh <<= bitcount;
2804 0 : info->freehigh <<= bitcount;
2805 :
2806 : out:
2807 0 : return 0;
2808 : }
2809 :
2810 0 : SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info)
2811 : {
2812 : struct sysinfo val;
2813 :
2814 0 : do_sysinfo(&val);
2815 :
2816 0 : if (copy_to_user(info, &val, sizeof(struct sysinfo)))
2817 : return -EFAULT;
2818 :
2819 0 : return 0;
2820 : }
2821 :
2822 : #ifdef CONFIG_COMPAT
2823 : struct compat_sysinfo {
2824 : s32 uptime;
2825 : u32 loads[3];
2826 : u32 totalram;
2827 : u32 freeram;
2828 : u32 sharedram;
2829 : u32 bufferram;
2830 : u32 totalswap;
2831 : u32 freeswap;
2832 : u16 procs;
2833 : u16 pad;
2834 : u32 totalhigh;
2835 : u32 freehigh;
2836 : u32 mem_unit;
2837 : char _f[20-2*sizeof(u32)-sizeof(int)];
2838 : };
2839 :
2840 : COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
2841 : {
2842 : struct sysinfo s;
2843 : struct compat_sysinfo s_32;
2844 :
2845 : do_sysinfo(&s);
2846 :
2847 : /* Check to see if any memory value is too large for 32-bit and scale
2848 : * down if needed
2849 : */
2850 : if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) {
2851 : int bitcount = 0;
2852 :
2853 : while (s.mem_unit < PAGE_SIZE) {
2854 : s.mem_unit <<= 1;
2855 : bitcount++;
2856 : }
2857 :
2858 : s.totalram >>= bitcount;
2859 : s.freeram >>= bitcount;
2860 : s.sharedram >>= bitcount;
2861 : s.bufferram >>= bitcount;
2862 : s.totalswap >>= bitcount;
2863 : s.freeswap >>= bitcount;
2864 : s.totalhigh >>= bitcount;
2865 : s.freehigh >>= bitcount;
2866 : }
2867 :
2868 : memset(&s_32, 0, sizeof(s_32));
2869 : s_32.uptime = s.uptime;
2870 : s_32.loads[0] = s.loads[0];
2871 : s_32.loads[1] = s.loads[1];
2872 : s_32.loads[2] = s.loads[2];
2873 : s_32.totalram = s.totalram;
2874 : s_32.freeram = s.freeram;
2875 : s_32.sharedram = s.sharedram;
2876 : s_32.bufferram = s.bufferram;
2877 : s_32.totalswap = s.totalswap;
2878 : s_32.freeswap = s.freeswap;
2879 : s_32.procs = s.procs;
2880 : s_32.totalhigh = s.totalhigh;
2881 : s_32.freehigh = s.freehigh;
2882 : s_32.mem_unit = s.mem_unit;
2883 : if (copy_to_user(info, &s_32, sizeof(s_32)))
2884 : return -EFAULT;
2885 : return 0;
2886 : }
2887 : #endif /* CONFIG_COMPAT */
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