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/utsname.h>
11 : #include <linux/mman.h>
12 : #include <linux/reboot.h>
13 : #include <linux/prctl.h>
14 : #include <linux/highuid.h>
15 : #include <linux/fs.h>
16 : #include <linux/kmod.h>
17 : #include <linux/perf_event.h>
18 : #include <linux/resource.h>
19 : #include <linux/kernel.h>
20 : #include <linux/workqueue.h>
21 : #include <linux/capability.h>
22 : #include <linux/device.h>
23 : #include <linux/key.h>
24 : #include <linux/times.h>
25 : #include <linux/posix-timers.h>
26 : #include <linux/security.h>
27 : #include <linux/suspend.h>
28 : #include <linux/tty.h>
29 : #include <linux/signal.h>
30 : #include <linux/cn_proc.h>
31 : #include <linux/getcpu.h>
32 : #include <linux/task_io_accounting_ops.h>
33 : #include <linux/seccomp.h>
34 : #include <linux/cpu.h>
35 : #include <linux/personality.h>
36 : #include <linux/ptrace.h>
37 : #include <linux/fs_struct.h>
38 : #include <linux/file.h>
39 : #include <linux/mount.h>
40 : #include <linux/gfp.h>
41 : #include <linux/syscore_ops.h>
42 : #include <linux/version.h>
43 : #include <linux/ctype.h>
44 : #include <linux/syscall_user_dispatch.h>
45 :
46 : #include <linux/compat.h>
47 : #include <linux/syscalls.h>
48 : #include <linux/kprobes.h>
49 : #include <linux/user_namespace.h>
50 : #include <linux/time_namespace.h>
51 : #include <linux/binfmts.h>
52 :
53 : #include <linux/sched.h>
54 : #include <linux/sched/autogroup.h>
55 : #include <linux/sched/loadavg.h>
56 : #include <linux/sched/stat.h>
57 : #include <linux/sched/mm.h>
58 : #include <linux/sched/coredump.h>
59 : #include <linux/sched/task.h>
60 : #include <linux/sched/cputime.h>
61 : #include <linux/rcupdate.h>
62 : #include <linux/uidgid.h>
63 : #include <linux/cred.h>
64 :
65 : #include <linux/nospec.h>
66 :
67 : #include <linux/kmsg_dump.h>
68 : /* Move somewhere else to avoid recompiling? */
69 : #include <generated/utsrelease.h>
70 :
71 : #include <linux/uaccess.h>
72 : #include <asm/io.h>
73 : #include <asm/unistd.h>
74 :
75 : #include "uid16.h"
76 :
77 : #ifndef SET_UNALIGN_CTL
78 : # define SET_UNALIGN_CTL(a, b) (-EINVAL)
79 : #endif
80 : #ifndef GET_UNALIGN_CTL
81 : # define GET_UNALIGN_CTL(a, b) (-EINVAL)
82 : #endif
83 : #ifndef SET_FPEMU_CTL
84 : # define SET_FPEMU_CTL(a, b) (-EINVAL)
85 : #endif
86 : #ifndef GET_FPEMU_CTL
87 : # define GET_FPEMU_CTL(a, b) (-EINVAL)
88 : #endif
89 : #ifndef SET_FPEXC_CTL
90 : # define SET_FPEXC_CTL(a, b) (-EINVAL)
91 : #endif
92 : #ifndef GET_FPEXC_CTL
93 : # define GET_FPEXC_CTL(a, b) (-EINVAL)
94 : #endif
95 : #ifndef GET_ENDIAN
96 : # define GET_ENDIAN(a, b) (-EINVAL)
97 : #endif
98 : #ifndef SET_ENDIAN
99 : # define SET_ENDIAN(a, b) (-EINVAL)
100 : #endif
101 : #ifndef GET_TSC_CTL
102 : # define GET_TSC_CTL(a) (-EINVAL)
103 : #endif
104 : #ifndef SET_TSC_CTL
105 : # define SET_TSC_CTL(a) (-EINVAL)
106 : #endif
107 : #ifndef GET_FP_MODE
108 : # define GET_FP_MODE(a) (-EINVAL)
109 : #endif
110 : #ifndef SET_FP_MODE
111 : # define SET_FP_MODE(a,b) (-EINVAL)
112 : #endif
113 : #ifndef SVE_SET_VL
114 : # define SVE_SET_VL(a) (-EINVAL)
115 : #endif
116 : #ifndef SVE_GET_VL
117 : # define SVE_GET_VL() (-EINVAL)
118 : #endif
119 : #ifndef PAC_RESET_KEYS
120 : # define PAC_RESET_KEYS(a, b) (-EINVAL)
121 : #endif
122 : #ifndef SET_TAGGED_ADDR_CTRL
123 : # define SET_TAGGED_ADDR_CTRL(a) (-EINVAL)
124 : #endif
125 : #ifndef GET_TAGGED_ADDR_CTRL
126 : # define GET_TAGGED_ADDR_CTRL() (-EINVAL)
127 : #endif
128 :
129 : /*
130 : * this is where the system-wide overflow UID and GID are defined, for
131 : * architectures that now have 32-bit UID/GID but didn't in the past
132 : */
133 :
134 : int overflowuid = DEFAULT_OVERFLOWUID;
135 : int overflowgid = DEFAULT_OVERFLOWGID;
136 :
137 : EXPORT_SYMBOL(overflowuid);
138 : EXPORT_SYMBOL(overflowgid);
139 :
140 : /*
141 : * the same as above, but for filesystems which can only store a 16-bit
142 : * UID and GID. as such, this is needed on all architectures
143 : */
144 :
145 : int fs_overflowuid = DEFAULT_FS_OVERFLOWUID;
146 : int fs_overflowgid = DEFAULT_FS_OVERFLOWGID;
147 :
148 : EXPORT_SYMBOL(fs_overflowuid);
149 : EXPORT_SYMBOL(fs_overflowgid);
150 :
151 : /*
152 : * Returns true if current's euid is same as p's uid or euid,
153 : * or has CAP_SYS_NICE to p's user_ns.
154 : *
155 : * Called with rcu_read_lock, creds are safe
156 : */
157 9 : static bool set_one_prio_perm(struct task_struct *p)
158 : {
159 9 : const struct cred *cred = current_cred(), *pcred = __task_cred(p);
160 :
161 9 : if (uid_eq(pcred->uid, cred->euid) ||
162 0 : uid_eq(pcred->euid, cred->euid))
163 : return true;
164 0 : if (ns_capable(pcred->user_ns, CAP_SYS_NICE))
165 0 : return true;
166 : return false;
167 : }
168 :
169 : /*
170 : * set the priority of a task
171 : * - the caller must hold the RCU read lock
172 : */
173 9 : static int set_one_prio(struct task_struct *p, int niceval, int error)
174 : {
175 9 : int no_nice;
176 :
177 9 : if (!set_one_prio_perm(p)) {
178 0 : error = -EPERM;
179 0 : goto out;
180 : }
181 9 : if (niceval < task_nice(p) && !can_nice(p, niceval)) {
182 0 : error = -EACCES;
183 0 : goto out;
184 : }
185 9 : no_nice = security_task_setnice(p, niceval);
186 9 : if (no_nice) {
187 0 : error = no_nice;
188 0 : goto out;
189 : }
190 9 : if (error == -ESRCH)
191 9 : error = 0;
192 9 : set_user_nice(p, niceval);
193 9 : out:
194 9 : return error;
195 : }
196 :
197 18 : SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
198 : {
199 9 : struct task_struct *g, *p;
200 9 : struct user_struct *user;
201 9 : const struct cred *cred = current_cred();
202 9 : int error = -EINVAL;
203 9 : struct pid *pgrp;
204 9 : kuid_t uid;
205 :
206 9 : if (which > PRIO_USER || which < PRIO_PROCESS)
207 0 : goto out;
208 :
209 : /* normalize: avoid signed division (rounding problems) */
210 9 : error = -ESRCH;
211 9 : if (niceval < MIN_NICE)
212 : niceval = MIN_NICE;
213 : if (niceval > MAX_NICE)
214 : niceval = MAX_NICE;
215 :
216 9 : rcu_read_lock();
217 9 : read_lock(&tasklist_lock);
218 9 : switch (which) {
219 9 : case PRIO_PROCESS:
220 9 : if (who)
221 0 : p = find_task_by_vpid(who);
222 : else
223 9 : p = current;
224 9 : if (p)
225 9 : error = set_one_prio(p, niceval, error);
226 : break;
227 0 : case PRIO_PGRP:
228 0 : if (who)
229 0 : pgrp = find_vpid(who);
230 : else
231 0 : pgrp = task_pgrp(current);
232 0 : do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
233 0 : error = set_one_prio(p, niceval, error);
234 0 : } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
235 : break;
236 0 : case PRIO_USER:
237 0 : uid = make_kuid(cred->user_ns, who);
238 0 : user = cred->user;
239 0 : if (!who)
240 0 : uid = cred->uid;
241 0 : else if (!uid_eq(uid, cred->uid)) {
242 0 : user = find_user(uid);
243 0 : if (!user)
244 0 : goto out_unlock; /* No processes for this user */
245 : }
246 0 : do_each_thread(g, p) {
247 0 : if (uid_eq(task_uid(p), uid) && task_pid_vnr(p))
248 0 : error = set_one_prio(p, niceval, error);
249 0 : } while_each_thread(g, p);
250 0 : if (!uid_eq(uid, cred->uid))
251 0 : free_uid(user); /* For find_user() */
252 : break;
253 : }
254 9 : out_unlock:
255 9 : read_unlock(&tasklist_lock);
256 9 : rcu_read_unlock();
257 9 : out:
258 9 : return error;
259 : }
260 :
261 : /*
262 : * Ugh. To avoid negative return values, "getpriority()" will
263 : * not return the normal nice-value, but a negated value that
264 : * has been offset by 20 (ie it returns 40..1 instead of -20..19)
265 : * to stay compatible.
266 : */
267 12 : SYSCALL_DEFINE2(getpriority, int, which, int, who)
268 : {
269 6 : struct task_struct *g, *p;
270 6 : struct user_struct *user;
271 6 : const struct cred *cred = current_cred();
272 6 : long niceval, retval = -ESRCH;
273 6 : struct pid *pgrp;
274 6 : kuid_t uid;
275 :
276 6 : if (which > PRIO_USER || which < PRIO_PROCESS)
277 : return -EINVAL;
278 :
279 6 : rcu_read_lock();
280 6 : read_lock(&tasklist_lock);
281 6 : switch (which) {
282 6 : case PRIO_PROCESS:
283 6 : if (who)
284 0 : p = find_task_by_vpid(who);
285 : else
286 6 : p = current;
287 6 : if (p) {
288 6 : niceval = nice_to_rlimit(task_nice(p));
289 6 : if (niceval > retval)
290 : retval = niceval;
291 : }
292 : break;
293 0 : case PRIO_PGRP:
294 0 : if (who)
295 0 : pgrp = find_vpid(who);
296 : else
297 0 : pgrp = task_pgrp(current);
298 0 : do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
299 0 : niceval = nice_to_rlimit(task_nice(p));
300 0 : if (niceval > retval)
301 : retval = niceval;
302 0 : } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
303 : break;
304 0 : case PRIO_USER:
305 0 : uid = make_kuid(cred->user_ns, who);
306 0 : user = cred->user;
307 0 : if (!who)
308 0 : uid = cred->uid;
309 0 : else if (!uid_eq(uid, cred->uid)) {
310 0 : user = find_user(uid);
311 0 : if (!user)
312 0 : goto out_unlock; /* No processes for this user */
313 : }
314 0 : do_each_thread(g, p) {
315 0 : if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) {
316 0 : niceval = nice_to_rlimit(task_nice(p));
317 0 : if (niceval > retval)
318 : retval = niceval;
319 : }
320 0 : } while_each_thread(g, p);
321 0 : if (!uid_eq(uid, cred->uid))
322 0 : free_uid(user); /* for find_user() */
323 : break;
324 : }
325 6 : out_unlock:
326 6 : read_unlock(&tasklist_lock);
327 6 : rcu_read_unlock();
328 :
329 6 : return retval;
330 : }
331 :
332 : /*
333 : * Unprivileged users may change the real gid to the effective gid
334 : * or vice versa. (BSD-style)
335 : *
336 : * If you set the real gid at all, or set the effective gid to a value not
337 : * equal to the real gid, then the saved gid is set to the new effective gid.
338 : *
339 : * This makes it possible for a setgid program to completely drop its
340 : * privileges, which is often a useful assertion to make when you are doing
341 : * a security audit over a program.
342 : *
343 : * The general idea is that a program which uses just setregid() will be
344 : * 100% compatible with BSD. A program which uses just setgid() will be
345 : * 100% compatible with POSIX with saved IDs.
346 : *
347 : * SMP: There are not races, the GIDs are checked only by filesystem
348 : * operations (as far as semantic preservation is concerned).
349 : */
350 : #ifdef CONFIG_MULTIUSER
351 11 : long __sys_setregid(gid_t rgid, gid_t egid)
352 : {
353 11 : struct user_namespace *ns = current_user_ns();
354 11 : const struct cred *old;
355 11 : struct cred *new;
356 11 : int retval;
357 11 : kgid_t krgid, kegid;
358 :
359 11 : krgid = make_kgid(ns, rgid);
360 11 : kegid = make_kgid(ns, egid);
361 :
362 11 : if ((rgid != (gid_t) -1) && !gid_valid(krgid))
363 : return -EINVAL;
364 11 : if ((egid != (gid_t) -1) && !gid_valid(kegid))
365 : return -EINVAL;
366 :
367 11 : new = prepare_creds();
368 11 : if (!new)
369 : return -ENOMEM;
370 11 : old = current_cred();
371 :
372 11 : retval = -EPERM;
373 11 : if (rgid != (gid_t) -1) {
374 11 : if (gid_eq(old->gid, krgid) ||
375 14 : gid_eq(old->egid, krgid) ||
376 4 : ns_capable_setid(old->user_ns, CAP_SETGID))
377 11 : new->gid = krgid;
378 : else
379 0 : goto error;
380 : }
381 11 : if (egid != (gid_t) -1) {
382 3 : if (gid_eq(old->gid, kegid) ||
383 1 : gid_eq(old->egid, kegid) ||
384 2 : gid_eq(old->sgid, kegid) ||
385 1 : ns_capable_setid(old->user_ns, CAP_SETGID))
386 3 : new->egid = kegid;
387 : else
388 0 : goto error;
389 : }
390 :
391 11 : if (rgid != (gid_t) -1 ||
392 0 : (egid != (gid_t) -1 && !gid_eq(kegid, old->gid)))
393 11 : new->sgid = new->egid;
394 11 : new->fsgid = new->egid;
395 :
396 11 : retval = security_task_fix_setgid(new, old, LSM_SETID_RE);
397 11 : if (retval < 0)
398 0 : goto error;
399 :
400 11 : return commit_creds(new);
401 :
402 0 : error:
403 0 : abort_creds(new);
404 0 : return retval;
405 : }
406 :
407 22 : SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
408 : {
409 11 : return __sys_setregid(rgid, egid);
410 : }
411 :
412 : /*
413 : * setgid() is implemented like SysV w/ SAVED_IDS
414 : *
415 : * SMP: Same implicit races as above.
416 : */
417 52 : long __sys_setgid(gid_t gid)
418 : {
419 52 : struct user_namespace *ns = current_user_ns();
420 52 : const struct cred *old;
421 52 : struct cred *new;
422 52 : int retval;
423 52 : kgid_t kgid;
424 :
425 52 : kgid = make_kgid(ns, gid);
426 52 : if (!gid_valid(kgid))
427 : return -EINVAL;
428 :
429 52 : new = prepare_creds();
430 52 : if (!new)
431 : return -ENOMEM;
432 52 : old = current_cred();
433 :
434 52 : retval = -EPERM;
435 52 : if (ns_capable_setid(old->user_ns, CAP_SETGID))
436 48 : new->gid = new->egid = new->sgid = new->fsgid = kgid;
437 4 : else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid))
438 0 : new->egid = new->fsgid = kgid;
439 : else
440 4 : goto error;
441 :
442 48 : retval = security_task_fix_setgid(new, old, LSM_SETID_ID);
443 48 : if (retval < 0)
444 0 : goto error;
445 :
446 48 : return commit_creds(new);
447 :
448 4 : error:
449 4 : abort_creds(new);
450 4 : return retval;
451 : }
452 :
453 104 : SYSCALL_DEFINE1(setgid, gid_t, gid)
454 : {
455 52 : return __sys_setgid(gid);
456 : }
457 :
458 : /*
459 : * change the user struct in a credentials set to match the new UID
460 : */
461 20 : static int set_user(struct cred *new)
462 : {
463 20 : struct user_struct *new_user;
464 :
465 20 : new_user = alloc_uid(new->uid);
466 20 : if (!new_user)
467 : return -EAGAIN;
468 :
469 : /*
470 : * We don't fail in case of NPROC limit excess here because too many
471 : * poorly written programs don't check set*uid() return code, assuming
472 : * it never fails if called by root. We may still enforce NPROC limit
473 : * for programs doing set*uid()+execve() by harmlessly deferring the
474 : * failure to the execve() stage.
475 : */
476 20 : if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) &&
477 : new_user != INIT_USER)
478 0 : current->flags |= PF_NPROC_EXCEEDED;
479 : else
480 20 : current->flags &= ~PF_NPROC_EXCEEDED;
481 :
482 20 : free_uid(new->user);
483 20 : new->user = new_user;
484 20 : return 0;
485 : }
486 :
487 : /*
488 : * Unprivileged users may change the real uid to the effective uid
489 : * or vice versa. (BSD-style)
490 : *
491 : * If you set the real uid at all, or set the effective uid to a value not
492 : * equal to the real uid, then the saved uid is set to the new effective uid.
493 : *
494 : * This makes it possible for a setuid program to completely drop its
495 : * privileges, which is often a useful assertion to make when you are doing
496 : * a security audit over a program.
497 : *
498 : * The general idea is that a program which uses just setreuid() will be
499 : * 100% compatible with BSD. A program which uses just setuid() will be
500 : * 100% compatible with POSIX with saved IDs.
501 : */
502 11 : long __sys_setreuid(uid_t ruid, uid_t euid)
503 : {
504 11 : struct user_namespace *ns = current_user_ns();
505 11 : const struct cred *old;
506 11 : struct cred *new;
507 11 : int retval;
508 11 : kuid_t kruid, keuid;
509 :
510 11 : kruid = make_kuid(ns, ruid);
511 11 : keuid = make_kuid(ns, euid);
512 :
513 11 : if ((ruid != (uid_t) -1) && !uid_valid(kruid))
514 : return -EINVAL;
515 11 : if ((euid != (uid_t) -1) && !uid_valid(keuid))
516 : return -EINVAL;
517 :
518 11 : new = prepare_creds();
519 11 : if (!new)
520 : return -ENOMEM;
521 11 : old = current_cred();
522 :
523 11 : retval = -EPERM;
524 11 : if (ruid != (uid_t) -1) {
525 11 : new->uid = kruid;
526 11 : if (!uid_eq(old->uid, kruid) &&
527 14 : !uid_eq(old->euid, kruid) &&
528 4 : !ns_capable_setid(old->user_ns, CAP_SETUID))
529 0 : goto error;
530 : }
531 :
532 11 : if (euid != (uid_t) -1) {
533 3 : new->euid = keuid;
534 3 : if (!uid_eq(old->uid, keuid) &&
535 1 : !uid_eq(old->euid, keuid) &&
536 2 : !uid_eq(old->suid, keuid) &&
537 1 : !ns_capable_setid(old->user_ns, CAP_SETUID))
538 0 : goto error;
539 : }
540 :
541 11 : if (!uid_eq(new->uid, old->uid)) {
542 10 : retval = set_user(new);
543 10 : if (retval < 0)
544 0 : goto error;
545 : }
546 11 : if (ruid != (uid_t) -1 ||
547 0 : (euid != (uid_t) -1 && !uid_eq(keuid, old->uid)))
548 11 : new->suid = new->euid;
549 11 : new->fsuid = new->euid;
550 :
551 11 : retval = security_task_fix_setuid(new, old, LSM_SETID_RE);
552 11 : if (retval < 0)
553 0 : goto error;
554 :
555 11 : return commit_creds(new);
556 :
557 0 : error:
558 0 : abort_creds(new);
559 0 : return retval;
560 : }
561 :
562 22 : SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
563 : {
564 11 : return __sys_setreuid(ruid, euid);
565 : }
566 :
567 : /*
568 : * setuid() is implemented like SysV with SAVED_IDS
569 : *
570 : * Note that SAVED_ID's is deficient in that a setuid root program
571 : * like sendmail, for example, cannot set its uid to be a normal
572 : * user and then switch back, because if you're root, setuid() sets
573 : * the saved uid too. If you don't like this, blame the bright people
574 : * in the POSIX committee and/or USG. Note that the BSD-style setreuid()
575 : * will allow a root program to temporarily drop privileges and be able to
576 : * regain them by swapping the real and effective uid.
577 : */
578 10 : long __sys_setuid(uid_t uid)
579 : {
580 10 : struct user_namespace *ns = current_user_ns();
581 10 : const struct cred *old;
582 10 : struct cred *new;
583 10 : int retval;
584 10 : kuid_t kuid;
585 :
586 10 : kuid = make_kuid(ns, uid);
587 10 : if (!uid_valid(kuid))
588 : return -EINVAL;
589 :
590 10 : new = prepare_creds();
591 10 : if (!new)
592 : return -ENOMEM;
593 10 : old = current_cred();
594 :
595 10 : retval = -EPERM;
596 10 : if (ns_capable_setid(old->user_ns, CAP_SETUID)) {
597 6 : new->suid = new->uid = kuid;
598 6 : if (!uid_eq(kuid, old->uid)) {
599 2 : retval = set_user(new);
600 2 : if (retval < 0)
601 0 : goto error;
602 : }
603 4 : } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) {
604 4 : goto error;
605 : }
606 :
607 6 : new->fsuid = new->euid = kuid;
608 :
609 6 : retval = security_task_fix_setuid(new, old, LSM_SETID_ID);
610 6 : if (retval < 0)
611 0 : goto error;
612 :
613 6 : return commit_creds(new);
614 :
615 4 : error:
616 4 : abort_creds(new);
617 4 : return retval;
618 : }
619 :
620 20 : SYSCALL_DEFINE1(setuid, uid_t, uid)
621 : {
622 10 : return __sys_setuid(uid);
623 : }
624 :
625 :
626 : /*
627 : * This function implements a generic ability to update ruid, euid,
628 : * and suid. This allows you to implement the 4.4 compatible seteuid().
629 : */
630 45 : long __sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
631 : {
632 45 : struct user_namespace *ns = current_user_ns();
633 45 : const struct cred *old;
634 45 : struct cred *new;
635 45 : int retval;
636 45 : kuid_t kruid, keuid, ksuid;
637 :
638 45 : kruid = make_kuid(ns, ruid);
639 45 : keuid = make_kuid(ns, euid);
640 45 : ksuid = make_kuid(ns, suid);
641 :
642 45 : if ((ruid != (uid_t) -1) && !uid_valid(kruid))
643 : return -EINVAL;
644 :
645 45 : if ((euid != (uid_t) -1) && !uid_valid(keuid))
646 : return -EINVAL;
647 :
648 45 : if ((suid != (uid_t) -1) && !uid_valid(ksuid))
649 : return -EINVAL;
650 :
651 45 : new = prepare_creds();
652 45 : if (!new)
653 : return -ENOMEM;
654 :
655 45 : old = current_cred();
656 :
657 45 : retval = -EPERM;
658 45 : if (!ns_capable_setid(old->user_ns, CAP_SETUID)) {
659 8 : if (ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) &&
660 0 : !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid))
661 0 : goto error;
662 8 : if (euid != (uid_t) -1 && !uid_eq(keuid, old->uid) &&
663 4 : !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid))
664 4 : goto error;
665 4 : if (suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) &&
666 0 : !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid))
667 0 : goto error;
668 : }
669 :
670 41 : if (ruid != (uid_t) -1) {
671 14 : new->uid = kruid;
672 14 : if (!uid_eq(kruid, old->uid)) {
673 8 : retval = set_user(new);
674 8 : if (retval < 0)
675 0 : goto error;
676 : }
677 : }
678 41 : if (euid != (uid_t) -1)
679 41 : new->euid = keuid;
680 41 : if (suid != (uid_t) -1)
681 14 : new->suid = ksuid;
682 41 : new->fsuid = new->euid;
683 :
684 41 : retval = security_task_fix_setuid(new, old, LSM_SETID_RES);
685 41 : if (retval < 0)
686 0 : goto error;
687 :
688 41 : return commit_creds(new);
689 :
690 4 : error:
691 4 : abort_creds(new);
692 4 : return retval;
693 : }
694 :
695 90 : SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid)
696 : {
697 45 : return __sys_setresuid(ruid, euid, suid);
698 : }
699 :
700 2 : SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp)
701 : {
702 1 : const struct cred *cred = current_cred();
703 1 : int retval;
704 1 : uid_t ruid, euid, suid;
705 :
706 1 : ruid = from_kuid_munged(cred->user_ns, cred->uid);
707 1 : euid = from_kuid_munged(cred->user_ns, cred->euid);
708 1 : suid = from_kuid_munged(cred->user_ns, cred->suid);
709 :
710 1 : retval = put_user(ruid, ruidp);
711 1 : if (!retval) {
712 1 : retval = put_user(euid, euidp);
713 1 : if (!retval)
714 1 : return put_user(suid, suidp);
715 : }
716 0 : return retval;
717 : }
718 :
719 : /*
720 : * Same as above, but for rgid, egid, sgid.
721 : */
722 44 : long __sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
723 : {
724 44 : struct user_namespace *ns = current_user_ns();
725 44 : const struct cred *old;
726 44 : struct cred *new;
727 44 : int retval;
728 44 : kgid_t krgid, kegid, ksgid;
729 :
730 44 : krgid = make_kgid(ns, rgid);
731 44 : kegid = make_kgid(ns, egid);
732 44 : ksgid = make_kgid(ns, sgid);
733 :
734 44 : if ((rgid != (gid_t) -1) && !gid_valid(krgid))
735 : return -EINVAL;
736 44 : if ((egid != (gid_t) -1) && !gid_valid(kegid))
737 : return -EINVAL;
738 44 : if ((sgid != (gid_t) -1) && !gid_valid(ksgid))
739 : return -EINVAL;
740 :
741 44 : new = prepare_creds();
742 44 : if (!new)
743 : return -ENOMEM;
744 44 : old = current_cred();
745 :
746 44 : retval = -EPERM;
747 44 : if (!ns_capable_setid(old->user_ns, CAP_SETGID)) {
748 4 : if (rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) &&
749 0 : !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid))
750 0 : goto error;
751 4 : if (egid != (gid_t) -1 && !gid_eq(kegid, old->gid) &&
752 4 : !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid))
753 4 : goto error;
754 0 : if (sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) &&
755 0 : !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid))
756 0 : goto error;
757 : }
758 :
759 40 : if (rgid != (gid_t) -1)
760 14 : new->gid = krgid;
761 40 : if (egid != (gid_t) -1)
762 40 : new->egid = kegid;
763 40 : if (sgid != (gid_t) -1)
764 14 : new->sgid = ksgid;
765 40 : new->fsgid = new->egid;
766 :
767 40 : retval = security_task_fix_setgid(new, old, LSM_SETID_RES);
768 40 : if (retval < 0)
769 0 : goto error;
770 :
771 40 : return commit_creds(new);
772 :
773 4 : error:
774 4 : abort_creds(new);
775 4 : return retval;
776 : }
777 :
778 88 : SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid)
779 : {
780 44 : return __sys_setresgid(rgid, egid, sgid);
781 : }
782 :
783 2 : SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp)
784 : {
785 1 : const struct cred *cred = current_cred();
786 1 : int retval;
787 1 : gid_t rgid, egid, sgid;
788 :
789 1 : rgid = from_kgid_munged(cred->user_ns, cred->gid);
790 1 : egid = from_kgid_munged(cred->user_ns, cred->egid);
791 1 : sgid = from_kgid_munged(cred->user_ns, cred->sgid);
792 :
793 1 : retval = put_user(rgid, rgidp);
794 1 : if (!retval) {
795 1 : retval = put_user(egid, egidp);
796 1 : if (!retval)
797 1 : retval = put_user(sgid, sgidp);
798 : }
799 :
800 1 : return retval;
801 : }
802 :
803 :
804 : /*
805 : * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This
806 : * is used for "access()" and for the NFS daemon (letting nfsd stay at
807 : * whatever uid it wants to). It normally shadows "euid", except when
808 : * explicitly set by setfsuid() or for access..
809 : */
810 0 : long __sys_setfsuid(uid_t uid)
811 : {
812 0 : const struct cred *old;
813 0 : struct cred *new;
814 0 : uid_t old_fsuid;
815 0 : kuid_t kuid;
816 :
817 0 : old = current_cred();
818 0 : old_fsuid = from_kuid_munged(old->user_ns, old->fsuid);
819 :
820 0 : kuid = make_kuid(old->user_ns, uid);
821 0 : if (!uid_valid(kuid))
822 0 : return old_fsuid;
823 :
824 0 : new = prepare_creds();
825 0 : if (!new)
826 0 : return old_fsuid;
827 :
828 0 : if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) ||
829 0 : uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) ||
830 0 : ns_capable_setid(old->user_ns, CAP_SETUID)) {
831 0 : if (!uid_eq(kuid, old->fsuid)) {
832 0 : new->fsuid = kuid;
833 0 : if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0)
834 0 : goto change_okay;
835 : }
836 : }
837 :
838 0 : abort_creds(new);
839 0 : return old_fsuid;
840 :
841 0 : change_okay:
842 0 : commit_creds(new);
843 0 : return old_fsuid;
844 : }
845 :
846 0 : SYSCALL_DEFINE1(setfsuid, uid_t, uid)
847 : {
848 0 : return __sys_setfsuid(uid);
849 : }
850 :
851 : /*
852 : * Samma på svenska..
853 : */
854 0 : long __sys_setfsgid(gid_t gid)
855 : {
856 0 : const struct cred *old;
857 0 : struct cred *new;
858 0 : gid_t old_fsgid;
859 0 : kgid_t kgid;
860 :
861 0 : old = current_cred();
862 0 : old_fsgid = from_kgid_munged(old->user_ns, old->fsgid);
863 :
864 0 : kgid = make_kgid(old->user_ns, gid);
865 0 : if (!gid_valid(kgid))
866 0 : return old_fsgid;
867 :
868 0 : new = prepare_creds();
869 0 : if (!new)
870 0 : return old_fsgid;
871 :
872 0 : if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) ||
873 0 : gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) ||
874 0 : ns_capable_setid(old->user_ns, CAP_SETGID)) {
875 0 : if (!gid_eq(kgid, old->fsgid)) {
876 0 : new->fsgid = kgid;
877 0 : if (security_task_fix_setgid(new,old,LSM_SETID_FS) == 0)
878 0 : goto change_okay;
879 : }
880 : }
881 :
882 0 : abort_creds(new);
883 0 : return old_fsgid;
884 :
885 0 : change_okay:
886 0 : commit_creds(new);
887 0 : return old_fsgid;
888 : }
889 :
890 0 : SYSCALL_DEFINE1(setfsgid, gid_t, gid)
891 : {
892 0 : return __sys_setfsgid(gid);
893 : }
894 : #endif /* CONFIG_MULTIUSER */
895 :
896 : /**
897 : * sys_getpid - return the thread group id of the current process
898 : *
899 : * Note, despite the name, this returns the tgid not the pid. The tgid and
900 : * the pid are identical unless CLONE_THREAD was specified on clone() in
901 : * which case the tgid is the same in all threads of the same group.
902 : *
903 : * This is SMP safe as current->tgid does not change.
904 : */
905 1111 : SYSCALL_DEFINE0(getpid)
906 : {
907 1111 : return task_tgid_vnr(current);
908 : }
909 :
910 : /* Thread ID - the internal kernel "pid" */
911 50 : SYSCALL_DEFINE0(gettid)
912 : {
913 50 : return task_pid_vnr(current);
914 : }
915 :
916 : /*
917 : * Accessing ->real_parent is not SMP-safe, it could
918 : * change from under us. However, we can use a stale
919 : * value of ->real_parent under rcu_read_lock(), see
920 : * release_task()->call_rcu(delayed_put_task_struct).
921 : */
922 125 : SYSCALL_DEFINE0(getppid)
923 : {
924 125 : int pid;
925 :
926 125 : rcu_read_lock();
927 125 : pid = task_tgid_vnr(rcu_dereference(current->real_parent));
928 125 : rcu_read_unlock();
929 :
930 125 : return pid;
931 : }
932 :
933 659 : SYSCALL_DEFINE0(getuid)
934 : {
935 : /* Only we change this so SMP safe */
936 659 : return from_kuid_munged(current_user_ns(), current_uid());
937 : }
938 :
939 640 : SYSCALL_DEFINE0(geteuid)
940 : {
941 : /* Only we change this so SMP safe */
942 640 : return from_kuid_munged(current_user_ns(), current_euid());
943 : }
944 :
945 454 : SYSCALL_DEFINE0(getgid)
946 : {
947 : /* Only we change this so SMP safe */
948 454 : return from_kgid_munged(current_user_ns(), current_gid());
949 : }
950 :
951 363 : SYSCALL_DEFINE0(getegid)
952 : {
953 : /* Only we change this so SMP safe */
954 363 : return from_kgid_munged(current_user_ns(), current_egid());
955 : }
956 :
957 0 : static void do_sys_times(struct tms *tms)
958 : {
959 0 : u64 tgutime, tgstime, cutime, cstime;
960 :
961 0 : thread_group_cputime_adjusted(current, &tgutime, &tgstime);
962 0 : cutime = current->signal->cutime;
963 0 : cstime = current->signal->cstime;
964 0 : tms->tms_utime = nsec_to_clock_t(tgutime);
965 0 : tms->tms_stime = nsec_to_clock_t(tgstime);
966 0 : tms->tms_cutime = nsec_to_clock_t(cutime);
967 0 : tms->tms_cstime = nsec_to_clock_t(cstime);
968 0 : }
969 :
970 0 : SYSCALL_DEFINE1(times, struct tms __user *, tbuf)
971 : {
972 0 : if (tbuf) {
973 0 : struct tms tmp;
974 :
975 0 : do_sys_times(&tmp);
976 0 : if (copy_to_user(tbuf, &tmp, sizeof(struct tms)))
977 0 : return -EFAULT;
978 : }
979 0 : force_successful_syscall_return();
980 0 : return (long) jiffies_64_to_clock_t(get_jiffies_64());
981 : }
982 :
983 : #ifdef CONFIG_COMPAT
984 0 : static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
985 : {
986 0 : return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
987 : }
988 :
989 0 : COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
990 : {
991 0 : if (tbuf) {
992 0 : struct tms tms;
993 0 : struct compat_tms tmp;
994 :
995 0 : do_sys_times(&tms);
996 : /* Convert our struct tms to the compat version. */
997 0 : tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
998 0 : tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
999 0 : tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
1000 0 : tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
1001 0 : if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
1002 0 : return -EFAULT;
1003 : }
1004 0 : force_successful_syscall_return();
1005 0 : return compat_jiffies_to_clock_t(jiffies);
1006 : }
1007 : #endif
1008 :
1009 : /*
1010 : * This needs some heavy checking ...
1011 : * I just haven't the stomach for it. I also don't fully
1012 : * understand sessions/pgrp etc. Let somebody who does explain it.
1013 : *
1014 : * OK, I think I have the protection semantics right.... this is really
1015 : * only important on a multi-user system anyway, to make sure one user
1016 : * can't send a signal to a process owned by another. -TYT, 12/12/91
1017 : *
1018 : * !PF_FORKNOEXEC check to conform completely to POSIX.
1019 : */
1020 22 : SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid)
1021 : {
1022 11 : struct task_struct *p;
1023 11 : struct task_struct *group_leader = current->group_leader;
1024 11 : struct pid *pgrp;
1025 11 : int err;
1026 :
1027 11 : if (!pid)
1028 11 : pid = task_pid_vnr(group_leader);
1029 11 : if (!pgid)
1030 11 : pgid = pid;
1031 11 : if (pgid < 0)
1032 : return -EINVAL;
1033 11 : rcu_read_lock();
1034 :
1035 : /* From this point forward we keep holding onto the tasklist lock
1036 : * so that our parent does not change from under us. -DaveM
1037 : */
1038 11 : write_lock_irq(&tasklist_lock);
1039 :
1040 11 : err = -ESRCH;
1041 11 : p = find_task_by_vpid(pid);
1042 11 : if (!p)
1043 0 : goto out;
1044 :
1045 11 : err = -EINVAL;
1046 11 : if (!thread_group_leader(p))
1047 0 : goto out;
1048 :
1049 11 : if (same_thread_group(p->real_parent, group_leader)) {
1050 0 : err = -EPERM;
1051 0 : if (task_session(p) != task_session(group_leader))
1052 0 : goto out;
1053 0 : err = -EACCES;
1054 0 : if (!(p->flags & PF_FORKNOEXEC))
1055 0 : goto out;
1056 : } else {
1057 11 : err = -ESRCH;
1058 11 : if (p != group_leader)
1059 0 : goto out;
1060 : }
1061 :
1062 11 : err = -EPERM;
1063 11 : if (p->signal->leader)
1064 11 : goto out;
1065 :
1066 0 : pgrp = task_pid(p);
1067 0 : if (pgid != pid) {
1068 0 : struct task_struct *g;
1069 :
1070 0 : pgrp = find_vpid(pgid);
1071 0 : g = pid_task(pgrp, PIDTYPE_PGID);
1072 0 : if (!g || task_session(g) != task_session(group_leader))
1073 0 : goto out;
1074 : }
1075 :
1076 0 : err = security_task_setpgid(p, pgid);
1077 0 : if (err)
1078 0 : goto out;
1079 :
1080 0 : if (task_pgrp(p) != pgrp)
1081 0 : change_pid(p, PIDTYPE_PGID, pgrp);
1082 :
1083 : err = 0;
1084 11 : out:
1085 : /* All paths lead to here, thus we are safe. -DaveM */
1086 11 : write_unlock_irq(&tasklist_lock);
1087 11 : rcu_read_unlock();
1088 11 : return err;
1089 : }
1090 :
1091 6 : static int do_getpgid(pid_t pid)
1092 : {
1093 6 : struct task_struct *p;
1094 6 : struct pid *grp;
1095 6 : int retval;
1096 :
1097 6 : rcu_read_lock();
1098 6 : if (!pid)
1099 6 : grp = task_pgrp(current);
1100 : else {
1101 0 : retval = -ESRCH;
1102 0 : p = find_task_by_vpid(pid);
1103 0 : if (!p)
1104 0 : goto out;
1105 0 : grp = task_pgrp(p);
1106 0 : if (!grp)
1107 0 : goto out;
1108 :
1109 0 : retval = security_task_getpgid(p);
1110 0 : if (retval)
1111 0 : goto out;
1112 : }
1113 6 : retval = pid_vnr(grp);
1114 6 : out:
1115 6 : rcu_read_unlock();
1116 6 : return retval;
1117 : }
1118 :
1119 0 : SYSCALL_DEFINE1(getpgid, pid_t, pid)
1120 : {
1121 0 : return do_getpgid(pid);
1122 : }
1123 :
1124 : #ifdef __ARCH_WANT_SYS_GETPGRP
1125 :
1126 6 : SYSCALL_DEFINE0(getpgrp)
1127 : {
1128 6 : return do_getpgid(0);
1129 : }
1130 :
1131 : #endif
1132 :
1133 6 : SYSCALL_DEFINE1(getsid, pid_t, pid)
1134 : {
1135 3 : struct task_struct *p;
1136 3 : struct pid *sid;
1137 3 : int retval;
1138 :
1139 3 : rcu_read_lock();
1140 3 : if (!pid)
1141 3 : sid = task_session(current);
1142 : else {
1143 0 : retval = -ESRCH;
1144 0 : p = find_task_by_vpid(pid);
1145 0 : if (!p)
1146 0 : goto out;
1147 0 : sid = task_session(p);
1148 0 : if (!sid)
1149 0 : goto out;
1150 :
1151 0 : retval = security_task_getsid(p);
1152 0 : if (retval)
1153 0 : goto out;
1154 : }
1155 3 : retval = pid_vnr(sid);
1156 3 : out:
1157 3 : rcu_read_unlock();
1158 3 : return retval;
1159 : }
1160 :
1161 54 : static void set_special_pids(struct pid *pid)
1162 : {
1163 54 : struct task_struct *curr = current->group_leader;
1164 :
1165 54 : if (task_session(curr) != pid)
1166 54 : change_pid(curr, PIDTYPE_SID, pid);
1167 :
1168 54 : if (task_pgrp(curr) != pid)
1169 54 : change_pid(curr, PIDTYPE_PGID, pid);
1170 54 : }
1171 :
1172 54 : int ksys_setsid(void)
1173 : {
1174 54 : struct task_struct *group_leader = current->group_leader;
1175 54 : struct pid *sid = task_pid(group_leader);
1176 54 : pid_t session = pid_vnr(sid);
1177 54 : int err = -EPERM;
1178 :
1179 54 : write_lock_irq(&tasklist_lock);
1180 : /* Fail if I am already a session leader */
1181 54 : if (group_leader->signal->leader)
1182 0 : goto out;
1183 :
1184 : /* Fail if a process group id already exists that equals the
1185 : * proposed session id.
1186 : */
1187 54 : if (pid_task(sid, PIDTYPE_PGID))
1188 0 : goto out;
1189 :
1190 54 : group_leader->signal->leader = 1;
1191 54 : set_special_pids(sid);
1192 :
1193 54 : proc_clear_tty(group_leader);
1194 :
1195 54 : err = session;
1196 54 : out:
1197 54 : write_unlock_irq(&tasklist_lock);
1198 54 : if (err > 0) {
1199 54 : proc_sid_connector(group_leader);
1200 54 : sched_autogroup_create_attach(group_leader);
1201 : }
1202 54 : return err;
1203 : }
1204 :
1205 54 : SYSCALL_DEFINE0(setsid)
1206 : {
1207 54 : return ksys_setsid();
1208 : }
1209 :
1210 : DECLARE_RWSEM(uts_sem);
1211 :
1212 : #ifdef COMPAT_UTS_MACHINE
1213 : #define override_architecture(name) \
1214 : (personality(current->personality) == PER_LINUX32 && \
1215 : copy_to_user(name->machine, COMPAT_UTS_MACHINE, \
1216 : sizeof(COMPAT_UTS_MACHINE)))
1217 : #else
1218 : #define override_architecture(name) 0
1219 : #endif
1220 :
1221 : /*
1222 : * Work around broken programs that cannot handle "Linux 3.0".
1223 : * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
1224 : * And we map 4.x and later versions to 2.6.60+x, so 4.0/5.0/6.0/... would be
1225 : * 2.6.60.
1226 : */
1227 41 : static int override_release(char __user *release, size_t len)
1228 : {
1229 41 : int ret = 0;
1230 :
1231 41 : if (current->personality & UNAME26) {
1232 0 : const char *rest = UTS_RELEASE;
1233 0 : char buf[65] = { 0 };
1234 0 : int ndots = 0;
1235 0 : unsigned v;
1236 0 : size_t copy;
1237 :
1238 0 : while (*rest) {
1239 0 : if (*rest == '.' && ++ndots >= 3)
1240 : break;
1241 0 : if (!isdigit(*rest) && *rest != '.')
1242 : break;
1243 0 : rest++;
1244 : }
1245 0 : v = LINUX_VERSION_PATCHLEVEL + 60;
1246 0 : copy = clamp_t(size_t, len, 1, sizeof(buf));
1247 0 : copy = scnprintf(buf, copy, "2.6.%u%s", v, rest);
1248 0 : ret = copy_to_user(release, buf, copy + 1);
1249 : }
1250 41 : return ret;
1251 : }
1252 :
1253 82 : SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
1254 : {
1255 41 : struct new_utsname tmp;
1256 :
1257 41 : down_read(&uts_sem);
1258 41 : memcpy(&tmp, utsname(), sizeof(tmp));
1259 41 : up_read(&uts_sem);
1260 41 : if (copy_to_user(name, &tmp, sizeof(tmp)))
1261 : return -EFAULT;
1262 :
1263 41 : if (override_release(name->release, sizeof(name->release)))
1264 : return -EFAULT;
1265 41 : if (override_architecture(name))
1266 0 : return -EFAULT;
1267 : return 0;
1268 : }
1269 :
1270 : #ifdef __ARCH_WANT_SYS_OLD_UNAME
1271 : /*
1272 : * Old cruft
1273 : */
1274 0 : SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
1275 : {
1276 0 : struct old_utsname tmp;
1277 :
1278 0 : if (!name)
1279 : return -EFAULT;
1280 :
1281 0 : down_read(&uts_sem);
1282 0 : memcpy(&tmp, utsname(), sizeof(tmp));
1283 0 : up_read(&uts_sem);
1284 0 : if (copy_to_user(name, &tmp, sizeof(tmp)))
1285 : return -EFAULT;
1286 :
1287 0 : if (override_release(name->release, sizeof(name->release)))
1288 : return -EFAULT;
1289 0 : if (override_architecture(name))
1290 0 : return -EFAULT;
1291 : return 0;
1292 : }
1293 :
1294 0 : SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
1295 : {
1296 0 : struct oldold_utsname tmp;
1297 :
1298 0 : if (!name)
1299 : return -EFAULT;
1300 :
1301 0 : memset(&tmp, 0, sizeof(tmp));
1302 :
1303 0 : down_read(&uts_sem);
1304 0 : memcpy(&tmp.sysname, &utsname()->sysname, __OLD_UTS_LEN);
1305 0 : memcpy(&tmp.nodename, &utsname()->nodename, __OLD_UTS_LEN);
1306 0 : memcpy(&tmp.release, &utsname()->release, __OLD_UTS_LEN);
1307 0 : memcpy(&tmp.version, &utsname()->version, __OLD_UTS_LEN);
1308 0 : memcpy(&tmp.machine, &utsname()->machine, __OLD_UTS_LEN);
1309 0 : up_read(&uts_sem);
1310 0 : if (copy_to_user(name, &tmp, sizeof(tmp)))
1311 : return -EFAULT;
1312 :
1313 0 : if (override_architecture(name))
1314 : return -EFAULT;
1315 0 : if (override_release(name->release, sizeof(name->release)))
1316 0 : return -EFAULT;
1317 : return 0;
1318 : }
1319 : #endif
1320 :
1321 2 : SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
1322 : {
1323 1 : int errno;
1324 1 : char tmp[__NEW_UTS_LEN];
1325 :
1326 1 : if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1327 : return -EPERM;
1328 :
1329 1 : if (len < 0 || len > __NEW_UTS_LEN)
1330 : return -EINVAL;
1331 1 : errno = -EFAULT;
1332 2 : if (!copy_from_user(tmp, name, len)) {
1333 1 : struct new_utsname *u;
1334 :
1335 1 : down_write(&uts_sem);
1336 1 : u = utsname();
1337 1 : memcpy(u->nodename, tmp, len);
1338 1 : memset(u->nodename + len, 0, sizeof(u->nodename) - len);
1339 1 : errno = 0;
1340 1 : uts_proc_notify(UTS_PROC_HOSTNAME);
1341 1 : up_write(&uts_sem);
1342 : }
1343 1 : return errno;
1344 : }
1345 :
1346 : #ifdef __ARCH_WANT_SYS_GETHOSTNAME
1347 :
1348 0 : SYSCALL_DEFINE2(gethostname, char __user *, name, int, len)
1349 : {
1350 0 : int i;
1351 0 : struct new_utsname *u;
1352 0 : char tmp[__NEW_UTS_LEN + 1];
1353 :
1354 0 : if (len < 0)
1355 : return -EINVAL;
1356 0 : down_read(&uts_sem);
1357 0 : u = utsname();
1358 0 : i = 1 + strlen(u->nodename);
1359 0 : if (i > len)
1360 : i = len;
1361 0 : memcpy(tmp, u->nodename, i);
1362 0 : up_read(&uts_sem);
1363 0 : if (copy_to_user(name, tmp, i))
1364 0 : return -EFAULT;
1365 : return 0;
1366 : }
1367 :
1368 : #endif
1369 :
1370 : /*
1371 : * Only setdomainname; getdomainname can be implemented by calling
1372 : * uname()
1373 : */
1374 0 : SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len)
1375 : {
1376 0 : int errno;
1377 0 : char tmp[__NEW_UTS_LEN];
1378 :
1379 0 : if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1380 : return -EPERM;
1381 0 : if (len < 0 || len > __NEW_UTS_LEN)
1382 : return -EINVAL;
1383 :
1384 0 : errno = -EFAULT;
1385 0 : if (!copy_from_user(tmp, name, len)) {
1386 0 : struct new_utsname *u;
1387 :
1388 0 : down_write(&uts_sem);
1389 0 : u = utsname();
1390 0 : memcpy(u->domainname, tmp, len);
1391 0 : memset(u->domainname + len, 0, sizeof(u->domainname) - len);
1392 0 : errno = 0;
1393 0 : uts_proc_notify(UTS_PROC_DOMAINNAME);
1394 0 : up_write(&uts_sem);
1395 : }
1396 0 : return errno;
1397 : }
1398 :
1399 0 : SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1400 : {
1401 0 : struct rlimit value;
1402 0 : int ret;
1403 :
1404 0 : ret = do_prlimit(current, resource, NULL, &value);
1405 0 : if (!ret)
1406 0 : ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0;
1407 :
1408 0 : return ret;
1409 : }
1410 :
1411 : #ifdef CONFIG_COMPAT
1412 :
1413 0 : COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
1414 : struct compat_rlimit __user *, rlim)
1415 : {
1416 0 : struct rlimit r;
1417 0 : struct compat_rlimit r32;
1418 :
1419 0 : if (copy_from_user(&r32, rlim, sizeof(struct compat_rlimit)))
1420 : return -EFAULT;
1421 :
1422 0 : if (r32.rlim_cur == COMPAT_RLIM_INFINITY)
1423 0 : r.rlim_cur = RLIM_INFINITY;
1424 : else
1425 0 : r.rlim_cur = r32.rlim_cur;
1426 0 : if (r32.rlim_max == COMPAT_RLIM_INFINITY)
1427 0 : r.rlim_max = RLIM_INFINITY;
1428 : else
1429 0 : r.rlim_max = r32.rlim_max;
1430 0 : return do_prlimit(current, resource, &r, NULL);
1431 : }
1432 :
1433 0 : COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
1434 : struct compat_rlimit __user *, rlim)
1435 : {
1436 0 : struct rlimit r;
1437 0 : int ret;
1438 :
1439 0 : ret = do_prlimit(current, resource, NULL, &r);
1440 0 : if (!ret) {
1441 0 : struct compat_rlimit r32;
1442 0 : if (r.rlim_cur > COMPAT_RLIM_INFINITY)
1443 0 : r32.rlim_cur = COMPAT_RLIM_INFINITY;
1444 : else
1445 0 : r32.rlim_cur = r.rlim_cur;
1446 0 : if (r.rlim_max > COMPAT_RLIM_INFINITY)
1447 0 : r32.rlim_max = COMPAT_RLIM_INFINITY;
1448 : else
1449 0 : r32.rlim_max = r.rlim_max;
1450 :
1451 0 : if (copy_to_user(rlim, &r32, sizeof(struct compat_rlimit)))
1452 0 : return -EFAULT;
1453 : }
1454 0 : return ret;
1455 : }
1456 :
1457 : #endif
1458 :
1459 : #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
1460 :
1461 : /*
1462 : * Back compatibility for getrlimit. Needed for some apps.
1463 : */
1464 0 : SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1465 : struct rlimit __user *, rlim)
1466 : {
1467 0 : struct rlimit x;
1468 0 : if (resource >= RLIM_NLIMITS)
1469 : return -EINVAL;
1470 :
1471 0 : resource = array_index_nospec(resource, RLIM_NLIMITS);
1472 0 : task_lock(current->group_leader);
1473 0 : x = current->signal->rlim[resource];
1474 0 : task_unlock(current->group_leader);
1475 0 : if (x.rlim_cur > 0x7FFFFFFF)
1476 0 : x.rlim_cur = 0x7FFFFFFF;
1477 0 : if (x.rlim_max > 0x7FFFFFFF)
1478 0 : x.rlim_max = 0x7FFFFFFF;
1479 0 : return copy_to_user(rlim, &x, sizeof(x)) ? -EFAULT : 0;
1480 : }
1481 :
1482 : #ifdef CONFIG_COMPAT
1483 0 : COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1484 : struct compat_rlimit __user *, rlim)
1485 : {
1486 0 : struct rlimit r;
1487 :
1488 0 : if (resource >= RLIM_NLIMITS)
1489 : return -EINVAL;
1490 :
1491 0 : resource = array_index_nospec(resource, RLIM_NLIMITS);
1492 0 : task_lock(current->group_leader);
1493 0 : r = current->signal->rlim[resource];
1494 0 : task_unlock(current->group_leader);
1495 0 : if (r.rlim_cur > 0x7FFFFFFF)
1496 : r.rlim_cur = 0x7FFFFFFF;
1497 0 : if (r.rlim_max > 0x7FFFFFFF)
1498 : r.rlim_max = 0x7FFFFFFF;
1499 :
1500 0 : if (put_user(r.rlim_cur, &rlim->rlim_cur) ||
1501 0 : put_user(r.rlim_max, &rlim->rlim_max))
1502 0 : return -EFAULT;
1503 : return 0;
1504 : }
1505 : #endif
1506 :
1507 : #endif
1508 :
1509 440 : static inline bool rlim64_is_infinity(__u64 rlim64)
1510 : {
1511 : #if BITS_PER_LONG < 64
1512 : return rlim64 >= ULONG_MAX;
1513 : #else
1514 440 : return rlim64 == RLIM64_INFINITY;
1515 : #endif
1516 : }
1517 :
1518 1429 : static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64)
1519 : {
1520 1429 : if (rlim->rlim_cur == RLIM_INFINITY)
1521 49 : rlim64->rlim_cur = RLIM64_INFINITY;
1522 : else
1523 1380 : rlim64->rlim_cur = rlim->rlim_cur;
1524 1429 : if (rlim->rlim_max == RLIM_INFINITY)
1525 1344 : rlim64->rlim_max = RLIM64_INFINITY;
1526 : else
1527 85 : rlim64->rlim_max = rlim->rlim_max;
1528 : }
1529 :
1530 220 : static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim)
1531 : {
1532 220 : if (rlim64_is_infinity(rlim64->rlim_cur))
1533 35 : rlim->rlim_cur = RLIM_INFINITY;
1534 : else
1535 185 : rlim->rlim_cur = (unsigned long)rlim64->rlim_cur;
1536 220 : if (rlim64_is_infinity(rlim64->rlim_max))
1537 46 : rlim->rlim_max = RLIM_INFINITY;
1538 : else
1539 174 : rlim->rlim_max = (unsigned long)rlim64->rlim_max;
1540 : }
1541 :
1542 : /* make sure you are allowed to change @tsk limits before calling this */
1543 1649 : int do_prlimit(struct task_struct *tsk, unsigned int resource,
1544 : struct rlimit *new_rlim, struct rlimit *old_rlim)
1545 : {
1546 1649 : struct rlimit *rlim;
1547 1649 : int retval = 0;
1548 :
1549 1649 : if (resource >= RLIM_NLIMITS)
1550 : return -EINVAL;
1551 1649 : if (new_rlim) {
1552 220 : if (new_rlim->rlim_cur > new_rlim->rlim_max)
1553 : return -EINVAL;
1554 220 : if (resource == RLIMIT_NOFILE &&
1555 84 : new_rlim->rlim_max > sysctl_nr_open)
1556 : return -EPERM;
1557 : }
1558 :
1559 : /* protect tsk->signal and tsk->sighand from disappearing */
1560 1649 : read_lock(&tasklist_lock);
1561 1649 : if (!tsk->sighand) {
1562 0 : retval = -ESRCH;
1563 0 : goto out;
1564 : }
1565 :
1566 1649 : rlim = tsk->signal->rlim + resource;
1567 1649 : task_lock(tsk->group_leader);
1568 1649 : if (new_rlim) {
1569 : /* Keep the capable check against init_user_ns until
1570 : cgroups can contain all limits */
1571 233 : if (new_rlim->rlim_max > rlim->rlim_max &&
1572 13 : !capable(CAP_SYS_RESOURCE))
1573 : retval = -EPERM;
1574 : if (!retval)
1575 220 : retval = security_task_setrlimit(tsk, resource, new_rlim);
1576 : }
1577 220 : if (!retval) {
1578 1649 : if (old_rlim)
1579 1429 : *old_rlim = *rlim;
1580 1649 : if (new_rlim)
1581 220 : *rlim = *new_rlim;
1582 : }
1583 1649 : task_unlock(tsk->group_leader);
1584 :
1585 : /*
1586 : * RLIMIT_CPU handling. Arm the posix CPU timer if the limit is not
1587 : * infite. In case of RLIM_INFINITY the posix CPU timer code
1588 : * ignores the rlimit.
1589 : */
1590 1649 : if (!retval && new_rlim && resource == RLIMIT_CPU &&
1591 5 : new_rlim->rlim_cur != RLIM_INFINITY &&
1592 : IS_ENABLED(CONFIG_POSIX_TIMERS))
1593 0 : update_rlimit_cpu(tsk, new_rlim->rlim_cur);
1594 1649 : out:
1595 1649 : read_unlock(&tasklist_lock);
1596 1649 : return retval;
1597 : }
1598 :
1599 : /* rcu lock must be held */
1600 1649 : static int check_prlimit_permission(struct task_struct *task,
1601 : unsigned int flags)
1602 : {
1603 1649 : const struct cred *cred = current_cred(), *tcred;
1604 1649 : bool id_match;
1605 :
1606 1649 : if (current == task)
1607 : return 0;
1608 :
1609 0 : tcred = __task_cred(task);
1610 0 : id_match = (uid_eq(cred->uid, tcred->euid) &&
1611 0 : uid_eq(cred->uid, tcred->suid) &&
1612 0 : uid_eq(cred->uid, tcred->uid) &&
1613 0 : gid_eq(cred->gid, tcred->egid) &&
1614 0 : gid_eq(cred->gid, tcred->sgid) &&
1615 0 : gid_eq(cred->gid, tcred->gid));
1616 0 : if (!id_match && !ns_capable(tcred->user_ns, CAP_SYS_RESOURCE))
1617 : return -EPERM;
1618 :
1619 0 : return security_task_prlimit(cred, tcred, flags);
1620 : }
1621 :
1622 3298 : SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource,
1623 : const struct rlimit64 __user *, new_rlim,
1624 : struct rlimit64 __user *, old_rlim)
1625 : {
1626 1649 : struct rlimit64 old64, new64;
1627 1649 : struct rlimit old, new;
1628 1649 : struct task_struct *tsk;
1629 1649 : unsigned int checkflags = 0;
1630 1649 : int ret;
1631 :
1632 1649 : if (old_rlim)
1633 1429 : checkflags |= LSM_PRLIMIT_READ;
1634 :
1635 1649 : if (new_rlim) {
1636 220 : if (copy_from_user(&new64, new_rlim, sizeof(new64)))
1637 : return -EFAULT;
1638 220 : rlim64_to_rlim(&new64, &new);
1639 220 : checkflags |= LSM_PRLIMIT_WRITE;
1640 : }
1641 :
1642 1649 : rcu_read_lock();
1643 1649 : tsk = pid ? find_task_by_vpid(pid) : current;
1644 1649 : if (!tsk) {
1645 0 : rcu_read_unlock();
1646 0 : return -ESRCH;
1647 : }
1648 1649 : ret = check_prlimit_permission(tsk, checkflags);
1649 1649 : if (ret) {
1650 0 : rcu_read_unlock();
1651 0 : return ret;
1652 : }
1653 1649 : get_task_struct(tsk);
1654 1649 : rcu_read_unlock();
1655 :
1656 3298 : ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL,
1657 : old_rlim ? &old : NULL);
1658 :
1659 1649 : if (!ret && old_rlim) {
1660 1429 : rlim_to_rlim64(&old, &old64);
1661 1429 : if (copy_to_user(old_rlim, &old64, sizeof(old64)))
1662 0 : ret = -EFAULT;
1663 : }
1664 :
1665 1649 : put_task_struct(tsk);
1666 1649 : return ret;
1667 : }
1668 :
1669 0 : SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1670 : {
1671 0 : struct rlimit new_rlim;
1672 :
1673 0 : if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
1674 : return -EFAULT;
1675 0 : return do_prlimit(current, resource, &new_rlim, NULL);
1676 : }
1677 :
1678 : /*
1679 : * It would make sense to put struct rusage in the task_struct,
1680 : * except that would make the task_struct be *really big*. After
1681 : * task_struct gets moved into malloc'ed memory, it would
1682 : * make sense to do this. It will make moving the rest of the information
1683 : * a lot simpler! (Which we're not doing right now because we're not
1684 : * measuring them yet).
1685 : *
1686 : * When sampling multiple threads for RUSAGE_SELF, under SMP we might have
1687 : * races with threads incrementing their own counters. But since word
1688 : * reads are atomic, we either get new values or old values and we don't
1689 : * care which for the sums. We always take the siglock to protect reading
1690 : * the c* fields from p->signal from races with exit.c updating those
1691 : * fields when reaping, so a sample either gets all the additions of a
1692 : * given child after it's reaped, or none so this sample is before reaping.
1693 : *
1694 : * Locking:
1695 : * We need to take the siglock for CHILDEREN, SELF and BOTH
1696 : * for the cases current multithreaded, non-current single threaded
1697 : * non-current multithreaded. Thread traversal is now safe with
1698 : * the siglock held.
1699 : * Strictly speaking, we donot need to take the siglock if we are current and
1700 : * single threaded, as no one else can take our signal_struct away, no one
1701 : * else can reap the children to update signal->c* counters, and no one else
1702 : * can race with the signal-> fields. If we do not take any lock, the
1703 : * signal-> fields could be read out of order while another thread was just
1704 : * exiting. So we should place a read memory barrier when we avoid the lock.
1705 : * On the writer side, write memory barrier is implied in __exit_signal
1706 : * as __exit_signal releases the siglock spinlock after updating the signal->
1707 : * fields. But we don't do this yet to keep things simple.
1708 : *
1709 : */
1710 :
1711 2 : static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r)
1712 : {
1713 2 : r->ru_nvcsw += t->nvcsw;
1714 2 : r->ru_nivcsw += t->nivcsw;
1715 2 : r->ru_minflt += t->min_flt;
1716 2 : r->ru_majflt += t->maj_flt;
1717 2 : r->ru_inblock += task_io_get_inblock(t);
1718 2 : r->ru_oublock += task_io_get_oublock(t);
1719 2 : }
1720 :
1721 2 : void getrusage(struct task_struct *p, int who, struct rusage *r)
1722 : {
1723 2 : struct task_struct *t;
1724 2 : unsigned long flags;
1725 2 : u64 tgutime, tgstime, utime, stime;
1726 2 : unsigned long maxrss = 0;
1727 :
1728 2 : memset((char *)r, 0, sizeof (*r));
1729 2 : utime = stime = 0;
1730 :
1731 2 : if (who == RUSAGE_THREAD) {
1732 0 : task_cputime_adjusted(current, &utime, &stime);
1733 0 : accumulate_thread_rusage(p, r);
1734 0 : maxrss = p->signal->maxrss;
1735 0 : goto out;
1736 : }
1737 :
1738 2 : if (!lock_task_sighand(p, &flags))
1739 0 : return;
1740 :
1741 2 : switch (who) {
1742 1 : case RUSAGE_BOTH:
1743 : case RUSAGE_CHILDREN:
1744 1 : utime = p->signal->cutime;
1745 1 : stime = p->signal->cstime;
1746 1 : r->ru_nvcsw = p->signal->cnvcsw;
1747 1 : r->ru_nivcsw = p->signal->cnivcsw;
1748 1 : r->ru_minflt = p->signal->cmin_flt;
1749 1 : r->ru_majflt = p->signal->cmaj_flt;
1750 1 : r->ru_inblock = p->signal->cinblock;
1751 1 : r->ru_oublock = p->signal->coublock;
1752 1 : maxrss = p->signal->cmaxrss;
1753 :
1754 1 : if (who == RUSAGE_CHILDREN)
1755 : break;
1756 2 : fallthrough;
1757 :
1758 : case RUSAGE_SELF:
1759 2 : thread_group_cputime_adjusted(p, &tgutime, &tgstime);
1760 2 : utime += tgutime;
1761 2 : stime += tgstime;
1762 2 : r->ru_nvcsw += p->signal->nvcsw;
1763 2 : r->ru_nivcsw += p->signal->nivcsw;
1764 2 : r->ru_minflt += p->signal->min_flt;
1765 2 : r->ru_majflt += p->signal->maj_flt;
1766 2 : r->ru_inblock += p->signal->inblock;
1767 2 : r->ru_oublock += p->signal->oublock;
1768 2 : if (maxrss < p->signal->maxrss)
1769 2 : maxrss = p->signal->maxrss;
1770 : t = p;
1771 2 : do {
1772 2 : accumulate_thread_rusage(t, r);
1773 2 : } while_each_thread(p, t);
1774 : break;
1775 :
1776 0 : default:
1777 0 : BUG();
1778 : }
1779 2 : unlock_task_sighand(p, &flags);
1780 :
1781 2 : out:
1782 2 : r->ru_utime = ns_to_kernel_old_timeval(utime);
1783 2 : r->ru_stime = ns_to_kernel_old_timeval(stime);
1784 :
1785 2 : if (who != RUSAGE_CHILDREN) {
1786 2 : struct mm_struct *mm = get_task_mm(p);
1787 :
1788 2 : if (mm) {
1789 1 : setmax_mm_hiwater_rss(&maxrss, mm);
1790 1 : mmput(mm);
1791 : }
1792 : }
1793 2 : r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */
1794 : }
1795 :
1796 2 : SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru)
1797 : {
1798 1 : struct rusage r;
1799 :
1800 1 : if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1801 : who != RUSAGE_THREAD)
1802 : return -EINVAL;
1803 :
1804 1 : getrusage(current, who, &r);
1805 1 : return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
1806 : }
1807 :
1808 : #ifdef CONFIG_COMPAT
1809 0 : COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru)
1810 : {
1811 0 : struct rusage r;
1812 :
1813 0 : if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1814 : who != RUSAGE_THREAD)
1815 : return -EINVAL;
1816 :
1817 0 : getrusage(current, who, &r);
1818 0 : return put_compat_rusage(&r, ru);
1819 : }
1820 : #endif
1821 :
1822 2154 : SYSCALL_DEFINE1(umask, int, mask)
1823 : {
1824 1077 : mask = xchg(¤t->fs->umask, mask & S_IRWXUGO);
1825 1077 : return mask;
1826 : }
1827 :
1828 0 : static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
1829 : {
1830 0 : struct fd exe;
1831 0 : struct file *old_exe, *exe_file;
1832 0 : struct inode *inode;
1833 0 : int err;
1834 :
1835 0 : exe = fdget(fd);
1836 0 : if (!exe.file)
1837 : return -EBADF;
1838 :
1839 0 : inode = file_inode(exe.file);
1840 :
1841 : /*
1842 : * Because the original mm->exe_file points to executable file, make
1843 : * sure that this one is executable as well, to avoid breaking an
1844 : * overall picture.
1845 : */
1846 0 : err = -EACCES;
1847 0 : if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path))
1848 0 : goto exit;
1849 :
1850 0 : err = file_permission(exe.file, MAY_EXEC);
1851 0 : if (err)
1852 0 : goto exit;
1853 :
1854 : /*
1855 : * Forbid mm->exe_file change if old file still mapped.
1856 : */
1857 0 : exe_file = get_mm_exe_file(mm);
1858 0 : err = -EBUSY;
1859 0 : if (exe_file) {
1860 0 : struct vm_area_struct *vma;
1861 :
1862 0 : mmap_read_lock(mm);
1863 0 : for (vma = mm->mmap; vma; vma = vma->vm_next) {
1864 0 : if (!vma->vm_file)
1865 0 : continue;
1866 0 : if (path_equal(&vma->vm_file->f_path,
1867 0 : &exe_file->f_path))
1868 0 : goto exit_err;
1869 : }
1870 :
1871 0 : mmap_read_unlock(mm);
1872 0 : fput(exe_file);
1873 : }
1874 :
1875 0 : err = 0;
1876 : /* set the new file, lockless */
1877 0 : get_file(exe.file);
1878 0 : old_exe = xchg(&mm->exe_file, exe.file);
1879 0 : if (old_exe)
1880 0 : fput(old_exe);
1881 0 : exit:
1882 0 : fdput(exe);
1883 0 : return err;
1884 0 : exit_err:
1885 0 : mmap_read_unlock(mm);
1886 0 : fput(exe_file);
1887 0 : goto exit;
1888 : }
1889 :
1890 : /*
1891 : * Check arithmetic relations of passed addresses.
1892 : *
1893 : * WARNING: we don't require any capability here so be very careful
1894 : * in what is allowed for modification from userspace.
1895 : */
1896 125 : static int validate_prctl_map_addr(struct prctl_mm_map *prctl_map)
1897 : {
1898 125 : unsigned long mmap_max_addr = TASK_SIZE;
1899 125 : int error = -EINVAL, i;
1900 :
1901 125 : static const unsigned char offsets[] = {
1902 : offsetof(struct prctl_mm_map, start_code),
1903 : offsetof(struct prctl_mm_map, end_code),
1904 : offsetof(struct prctl_mm_map, start_data),
1905 : offsetof(struct prctl_mm_map, end_data),
1906 : offsetof(struct prctl_mm_map, start_brk),
1907 : offsetof(struct prctl_mm_map, brk),
1908 : offsetof(struct prctl_mm_map, start_stack),
1909 : offsetof(struct prctl_mm_map, arg_start),
1910 : offsetof(struct prctl_mm_map, arg_end),
1911 : offsetof(struct prctl_mm_map, env_start),
1912 : offsetof(struct prctl_mm_map, env_end),
1913 : };
1914 :
1915 : /*
1916 : * Make sure the members are not somewhere outside
1917 : * of allowed address space.
1918 : */
1919 1500 : for (i = 0; i < ARRAY_SIZE(offsets); i++) {
1920 1375 : u64 val = *(u64 *)((char *)prctl_map + offsets[i]);
1921 :
1922 1375 : if ((unsigned long)val >= mmap_max_addr ||
1923 1375 : (unsigned long)val < mmap_min_addr)
1924 0 : goto out;
1925 : }
1926 :
1927 : /*
1928 : * Make sure the pairs are ordered.
1929 : */
1930 : #define __prctl_check_order(__m1, __op, __m2) \
1931 : ((unsigned long)prctl_map->__m1 __op \
1932 : (unsigned long)prctl_map->__m2) ? 0 : -EINVAL
1933 125 : error = __prctl_check_order(start_code, <, end_code);
1934 125 : error |= __prctl_check_order(start_data,<=, end_data);
1935 125 : error |= __prctl_check_order(start_brk, <=, brk);
1936 125 : error |= __prctl_check_order(arg_start, <=, arg_end);
1937 125 : error |= __prctl_check_order(env_start, <=, env_end);
1938 125 : if (error)
1939 0 : goto out;
1940 : #undef __prctl_check_order
1941 :
1942 125 : error = -EINVAL;
1943 :
1944 : /*
1945 : * @brk should be after @end_data in traditional maps.
1946 : */
1947 125 : if (prctl_map->start_brk <= prctl_map->end_data ||
1948 : prctl_map->brk <= prctl_map->end_data)
1949 0 : goto out;
1950 :
1951 : /*
1952 : * Neither we should allow to override limits if they set.
1953 : */
1954 125 : if (check_data_rlimit(rlimit(RLIMIT_DATA), prctl_map->brk,
1955 : prctl_map->start_brk, prctl_map->end_data,
1956 : prctl_map->start_data))
1957 0 : goto out;
1958 :
1959 : error = 0;
1960 125 : out:
1961 125 : return error;
1962 : }
1963 :
1964 : #ifdef CONFIG_CHECKPOINT_RESTORE
1965 : static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size)
1966 : {
1967 : struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, };
1968 : unsigned long user_auxv[AT_VECTOR_SIZE];
1969 : struct mm_struct *mm = current->mm;
1970 : int error;
1971 :
1972 : BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
1973 : BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256);
1974 :
1975 : if (opt == PR_SET_MM_MAP_SIZE)
1976 : return put_user((unsigned int)sizeof(prctl_map),
1977 : (unsigned int __user *)addr);
1978 :
1979 : if (data_size != sizeof(prctl_map))
1980 : return -EINVAL;
1981 :
1982 : if (copy_from_user(&prctl_map, addr, sizeof(prctl_map)))
1983 : return -EFAULT;
1984 :
1985 : error = validate_prctl_map_addr(&prctl_map);
1986 : if (error)
1987 : return error;
1988 :
1989 : if (prctl_map.auxv_size) {
1990 : /*
1991 : * Someone is trying to cheat the auxv vector.
1992 : */
1993 : if (!prctl_map.auxv ||
1994 : prctl_map.auxv_size > sizeof(mm->saved_auxv))
1995 : return -EINVAL;
1996 :
1997 : memset(user_auxv, 0, sizeof(user_auxv));
1998 : if (copy_from_user(user_auxv,
1999 : (const void __user *)prctl_map.auxv,
2000 : prctl_map.auxv_size))
2001 : return -EFAULT;
2002 :
2003 : /* Last entry must be AT_NULL as specification requires */
2004 : user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL;
2005 : user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL;
2006 : }
2007 :
2008 : if (prctl_map.exe_fd != (u32)-1) {
2009 : /*
2010 : * Check if the current user is checkpoint/restore capable.
2011 : * At the time of this writing, it checks for CAP_SYS_ADMIN
2012 : * or CAP_CHECKPOINT_RESTORE.
2013 : * Note that a user with access to ptrace can masquerade an
2014 : * arbitrary program as any executable, even setuid ones.
2015 : * This may have implications in the tomoyo subsystem.
2016 : */
2017 : if (!checkpoint_restore_ns_capable(current_user_ns()))
2018 : return -EPERM;
2019 :
2020 : error = prctl_set_mm_exe_file(mm, prctl_map.exe_fd);
2021 : if (error)
2022 : return error;
2023 : }
2024 :
2025 : /*
2026 : * arg_lock protects concurent updates but we still need mmap_lock for
2027 : * read to exclude races with sys_brk.
2028 : */
2029 : mmap_read_lock(mm);
2030 :
2031 : /*
2032 : * We don't validate if these members are pointing to
2033 : * real present VMAs because application may have correspond
2034 : * VMAs already unmapped and kernel uses these members for statistics
2035 : * output in procfs mostly, except
2036 : *
2037 : * - @start_brk/@brk which are used in do_brk_flags but kernel lookups
2038 : * for VMAs when updating these memvers so anything wrong written
2039 : * here cause kernel to swear at userspace program but won't lead
2040 : * to any problem in kernel itself
2041 : */
2042 :
2043 : spin_lock(&mm->arg_lock);
2044 : mm->start_code = prctl_map.start_code;
2045 : mm->end_code = prctl_map.end_code;
2046 : mm->start_data = prctl_map.start_data;
2047 : mm->end_data = prctl_map.end_data;
2048 : mm->start_brk = prctl_map.start_brk;
2049 : mm->brk = prctl_map.brk;
2050 : mm->start_stack = prctl_map.start_stack;
2051 : mm->arg_start = prctl_map.arg_start;
2052 : mm->arg_end = prctl_map.arg_end;
2053 : mm->env_start = prctl_map.env_start;
2054 : mm->env_end = prctl_map.env_end;
2055 : spin_unlock(&mm->arg_lock);
2056 :
2057 : /*
2058 : * Note this update of @saved_auxv is lockless thus
2059 : * if someone reads this member in procfs while we're
2060 : * updating -- it may get partly updated results. It's
2061 : * known and acceptable trade off: we leave it as is to
2062 : * not introduce additional locks here making the kernel
2063 : * more complex.
2064 : */
2065 : if (prctl_map.auxv_size)
2066 : memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv));
2067 :
2068 : mmap_read_unlock(mm);
2069 : return 0;
2070 : }
2071 : #endif /* CONFIG_CHECKPOINT_RESTORE */
2072 :
2073 0 : static int prctl_set_auxv(struct mm_struct *mm, unsigned long addr,
2074 : unsigned long len)
2075 : {
2076 : /*
2077 : * This doesn't move the auxiliary vector itself since it's pinned to
2078 : * mm_struct, but it permits filling the vector with new values. It's
2079 : * up to the caller to provide sane values here, otherwise userspace
2080 : * tools which use this vector might be unhappy.
2081 : */
2082 0 : unsigned long user_auxv[AT_VECTOR_SIZE] = {};
2083 :
2084 0 : if (len > sizeof(user_auxv))
2085 : return -EINVAL;
2086 :
2087 0 : if (copy_from_user(user_auxv, (const void __user *)addr, len))
2088 : return -EFAULT;
2089 :
2090 : /* Make sure the last entry is always AT_NULL */
2091 0 : user_auxv[AT_VECTOR_SIZE - 2] = 0;
2092 0 : user_auxv[AT_VECTOR_SIZE - 1] = 0;
2093 :
2094 0 : BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
2095 :
2096 0 : task_lock(current);
2097 0 : memcpy(mm->saved_auxv, user_auxv, len);
2098 0 : task_unlock(current);
2099 :
2100 0 : return 0;
2101 : }
2102 :
2103 125 : static int prctl_set_mm(int opt, unsigned long addr,
2104 : unsigned long arg4, unsigned long arg5)
2105 : {
2106 125 : struct mm_struct *mm = current->mm;
2107 125 : struct prctl_mm_map prctl_map = {
2108 : .auxv = NULL,
2109 : .auxv_size = 0,
2110 : .exe_fd = -1,
2111 : };
2112 125 : struct vm_area_struct *vma;
2113 125 : int error;
2114 :
2115 125 : if (arg5 || (arg4 && (opt != PR_SET_MM_AUXV &&
2116 0 : opt != PR_SET_MM_MAP &&
2117 : opt != PR_SET_MM_MAP_SIZE)))
2118 : return -EINVAL;
2119 :
2120 : #ifdef CONFIG_CHECKPOINT_RESTORE
2121 : if (opt == PR_SET_MM_MAP || opt == PR_SET_MM_MAP_SIZE)
2122 : return prctl_set_mm_map(opt, (const void __user *)addr, arg4);
2123 : #endif
2124 :
2125 125 : if (!capable(CAP_SYS_RESOURCE))
2126 : return -EPERM;
2127 :
2128 125 : if (opt == PR_SET_MM_EXE_FILE)
2129 0 : return prctl_set_mm_exe_file(mm, (unsigned int)addr);
2130 :
2131 125 : if (opt == PR_SET_MM_AUXV)
2132 0 : return prctl_set_auxv(mm, addr, arg4);
2133 :
2134 125 : if (addr >= TASK_SIZE || addr < mmap_min_addr)
2135 : return -EINVAL;
2136 :
2137 125 : error = -EINVAL;
2138 :
2139 : /*
2140 : * arg_lock protects concurent updates of arg boundaries, we need
2141 : * mmap_lock for a) concurrent sys_brk, b) finding VMA for addr
2142 : * validation.
2143 : */
2144 125 : mmap_read_lock(mm);
2145 125 : vma = find_vma(mm, addr);
2146 :
2147 125 : spin_lock(&mm->arg_lock);
2148 125 : prctl_map.start_code = mm->start_code;
2149 125 : prctl_map.end_code = mm->end_code;
2150 125 : prctl_map.start_data = mm->start_data;
2151 125 : prctl_map.end_data = mm->end_data;
2152 125 : prctl_map.start_brk = mm->start_brk;
2153 125 : prctl_map.brk = mm->brk;
2154 125 : prctl_map.start_stack = mm->start_stack;
2155 125 : prctl_map.arg_start = mm->arg_start;
2156 125 : prctl_map.arg_end = mm->arg_end;
2157 125 : prctl_map.env_start = mm->env_start;
2158 125 : prctl_map.env_end = mm->env_end;
2159 :
2160 125 : switch (opt) {
2161 0 : case PR_SET_MM_START_CODE:
2162 0 : prctl_map.start_code = addr;
2163 0 : break;
2164 0 : case PR_SET_MM_END_CODE:
2165 0 : prctl_map.end_code = addr;
2166 0 : break;
2167 0 : case PR_SET_MM_START_DATA:
2168 0 : prctl_map.start_data = addr;
2169 0 : break;
2170 0 : case PR_SET_MM_END_DATA:
2171 0 : prctl_map.end_data = addr;
2172 0 : break;
2173 0 : case PR_SET_MM_START_STACK:
2174 0 : prctl_map.start_stack = addr;
2175 0 : break;
2176 0 : case PR_SET_MM_START_BRK:
2177 0 : prctl_map.start_brk = addr;
2178 0 : break;
2179 0 : case PR_SET_MM_BRK:
2180 0 : prctl_map.brk = addr;
2181 0 : break;
2182 55 : case PR_SET_MM_ARG_START:
2183 55 : prctl_map.arg_start = addr;
2184 55 : break;
2185 70 : case PR_SET_MM_ARG_END:
2186 70 : prctl_map.arg_end = addr;
2187 70 : break;
2188 0 : case PR_SET_MM_ENV_START:
2189 0 : prctl_map.env_start = addr;
2190 0 : break;
2191 0 : case PR_SET_MM_ENV_END:
2192 0 : prctl_map.env_end = addr;
2193 0 : break;
2194 0 : default:
2195 0 : goto out;
2196 : }
2197 :
2198 125 : error = validate_prctl_map_addr(&prctl_map);
2199 125 : if (error)
2200 0 : goto out;
2201 :
2202 125 : switch (opt) {
2203 : /*
2204 : * If command line arguments and environment
2205 : * are placed somewhere else on stack, we can
2206 : * set them up here, ARG_START/END to setup
2207 : * command line argumets and ENV_START/END
2208 : * for environment.
2209 : */
2210 125 : case PR_SET_MM_START_STACK:
2211 : case PR_SET_MM_ARG_START:
2212 : case PR_SET_MM_ARG_END:
2213 : case PR_SET_MM_ENV_START:
2214 : case PR_SET_MM_ENV_END:
2215 125 : if (!vma) {
2216 0 : error = -EFAULT;
2217 0 : goto out;
2218 : }
2219 : }
2220 :
2221 125 : mm->start_code = prctl_map.start_code;
2222 125 : mm->end_code = prctl_map.end_code;
2223 125 : mm->start_data = prctl_map.start_data;
2224 125 : mm->end_data = prctl_map.end_data;
2225 125 : mm->start_brk = prctl_map.start_brk;
2226 125 : mm->brk = prctl_map.brk;
2227 125 : mm->start_stack = prctl_map.start_stack;
2228 125 : mm->arg_start = prctl_map.arg_start;
2229 125 : mm->arg_end = prctl_map.arg_end;
2230 125 : mm->env_start = prctl_map.env_start;
2231 125 : mm->env_end = prctl_map.env_end;
2232 :
2233 125 : error = 0;
2234 125 : out:
2235 125 : spin_unlock(&mm->arg_lock);
2236 125 : mmap_read_unlock(mm);
2237 125 : return error;
2238 : }
2239 :
2240 : #ifdef CONFIG_CHECKPOINT_RESTORE
2241 : static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr)
2242 : {
2243 : return put_user(me->clear_child_tid, tid_addr);
2244 : }
2245 : #else
2246 : static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr)
2247 : {
2248 : return -EINVAL;
2249 : }
2250 : #endif
2251 :
2252 1 : static int propagate_has_child_subreaper(struct task_struct *p, void *data)
2253 : {
2254 : /*
2255 : * If task has has_child_subreaper - all its decendants
2256 : * already have these flag too and new decendants will
2257 : * inherit it on fork, skip them.
2258 : *
2259 : * If we've found child_reaper - skip descendants in
2260 : * it's subtree as they will never get out pidns.
2261 : */
2262 1 : if (p->signal->has_child_subreaper ||
2263 1 : is_child_reaper(task_pid(p)))
2264 : return 0;
2265 :
2266 1 : p->signal->has_child_subreaper = 1;
2267 1 : return 1;
2268 : }
2269 :
2270 0 : int __weak arch_prctl_spec_ctrl_get(struct task_struct *t, unsigned long which)
2271 : {
2272 0 : return -EINVAL;
2273 : }
2274 :
2275 0 : int __weak arch_prctl_spec_ctrl_set(struct task_struct *t, unsigned long which,
2276 : unsigned long ctrl)
2277 : {
2278 0 : return -EINVAL;
2279 : }
2280 :
2281 : #define PR_IO_FLUSHER (PF_MEMALLOC_NOIO | PF_LOCAL_THROTTLE)
2282 :
2283 1384 : SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
2284 : unsigned long, arg4, unsigned long, arg5)
2285 : {
2286 692 : struct task_struct *me = current;
2287 692 : unsigned char comm[sizeof(me->comm)];
2288 692 : long error;
2289 :
2290 692 : error = security_task_prctl(option, arg2, arg3, arg4, arg5);
2291 692 : if (error != -ENOSYS)
2292 : return error;
2293 :
2294 536 : error = 0;
2295 536 : switch (option) {
2296 : case PR_SET_PDEATHSIG:
2297 34 : if (!valid_signal(arg2)) {
2298 : error = -EINVAL;
2299 : break;
2300 : }
2301 34 : me->pdeath_signal = arg2;
2302 34 : break;
2303 0 : case PR_GET_PDEATHSIG:
2304 0 : error = put_user(me->pdeath_signal, (int __user *)arg2);
2305 0 : break;
2306 138 : case PR_GET_DUMPABLE:
2307 138 : error = get_dumpable(me->mm);
2308 138 : break;
2309 1 : case PR_SET_DUMPABLE:
2310 1 : if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) {
2311 : error = -EINVAL;
2312 : break;
2313 : }
2314 1 : set_dumpable(me->mm, arg2);
2315 1 : break;
2316 :
2317 : case PR_SET_UNALIGN:
2318 : error = SET_UNALIGN_CTL(me, arg2);
2319 : break;
2320 : case PR_GET_UNALIGN:
2321 : error = GET_UNALIGN_CTL(me, arg2);
2322 : break;
2323 : case PR_SET_FPEMU:
2324 : error = SET_FPEMU_CTL(me, arg2);
2325 : break;
2326 : case PR_GET_FPEMU:
2327 : error = GET_FPEMU_CTL(me, arg2);
2328 : break;
2329 : case PR_SET_FPEXC:
2330 : error = SET_FPEXC_CTL(me, arg2);
2331 : break;
2332 : case PR_GET_FPEXC:
2333 : error = GET_FPEXC_CTL(me, arg2);
2334 : break;
2335 0 : case PR_GET_TIMING:
2336 0 : error = PR_TIMING_STATISTICAL;
2337 0 : break;
2338 0 : case PR_SET_TIMING:
2339 0 : if (arg2 != PR_TIMING_STATISTICAL)
2340 0 : error = -EINVAL;
2341 : break;
2342 76 : case PR_SET_NAME:
2343 76 : comm[sizeof(me->comm) - 1] = 0;
2344 76 : if (strncpy_from_user(comm, (char __user *)arg2,
2345 : sizeof(me->comm) - 1) < 0)
2346 : return -EFAULT;
2347 76 : set_task_comm(me, comm);
2348 692 : proc_comm_connector(me);
2349 : break;
2350 : case PR_GET_NAME:
2351 0 : get_task_comm(comm, me);
2352 0 : if (copy_to_user((char __user *)arg2, comm, sizeof(comm)))
2353 0 : return -EFAULT;
2354 : break;
2355 : case PR_GET_ENDIAN:
2356 : error = GET_ENDIAN(me, arg2);
2357 : break;
2358 : case PR_SET_ENDIAN:
2359 : error = SET_ENDIAN(me, arg2);
2360 : break;
2361 : case PR_GET_SECCOMP:
2362 : error = prctl_get_seccomp();
2363 : break;
2364 : case PR_SET_SECCOMP:
2365 692 : error = prctl_set_seccomp(arg2, (char __user *)arg3);
2366 : break;
2367 0 : case PR_GET_TSC:
2368 0 : error = GET_TSC_CTL(arg2);
2369 0 : break;
2370 0 : case PR_SET_TSC:
2371 0 : error = SET_TSC_CTL(arg2);
2372 0 : break;
2373 0 : case PR_TASK_PERF_EVENTS_DISABLE:
2374 0 : error = perf_event_task_disable();
2375 0 : break;
2376 0 : case PR_TASK_PERF_EVENTS_ENABLE:
2377 0 : error = perf_event_task_enable();
2378 0 : break;
2379 : case PR_GET_TIMERSLACK:
2380 1 : if (current->timer_slack_ns > ULONG_MAX)
2381 : error = ULONG_MAX;
2382 : else
2383 1 : error = current->timer_slack_ns;
2384 : break;
2385 0 : case PR_SET_TIMERSLACK:
2386 0 : if (arg2 <= 0)
2387 0 : current->timer_slack_ns =
2388 0 : current->default_timer_slack_ns;
2389 : else
2390 0 : current->timer_slack_ns = arg2;
2391 : break;
2392 0 : case PR_MCE_KILL:
2393 0 : if (arg4 | arg5)
2394 : return -EINVAL;
2395 0 : switch (arg2) {
2396 0 : case PR_MCE_KILL_CLEAR:
2397 0 : if (arg3 != 0)
2398 : return -EINVAL;
2399 0 : current->flags &= ~PF_MCE_PROCESS;
2400 0 : break;
2401 : case PR_MCE_KILL_SET:
2402 0 : current->flags |= PF_MCE_PROCESS;
2403 0 : if (arg3 == PR_MCE_KILL_EARLY)
2404 0 : current->flags |= PF_MCE_EARLY;
2405 0 : else if (arg3 == PR_MCE_KILL_LATE)
2406 0 : current->flags &= ~PF_MCE_EARLY;
2407 0 : else if (arg3 == PR_MCE_KILL_DEFAULT)
2408 0 : current->flags &=
2409 : ~(PF_MCE_EARLY|PF_MCE_PROCESS);
2410 : else
2411 : return -EINVAL;
2412 : break;
2413 : default:
2414 : return -EINVAL;
2415 : }
2416 : break;
2417 0 : case PR_MCE_KILL_GET:
2418 0 : if (arg2 | arg3 | arg4 | arg5)
2419 : return -EINVAL;
2420 0 : if (current->flags & PF_MCE_PROCESS)
2421 0 : error = (current->flags & PF_MCE_EARLY) ?
2422 0 : PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE;
2423 : else
2424 : error = PR_MCE_KILL_DEFAULT;
2425 : break;
2426 125 : case PR_SET_MM:
2427 125 : error = prctl_set_mm(arg2, arg3, arg4, arg5);
2428 125 : break;
2429 : case PR_GET_TID_ADDRESS:
2430 692 : error = prctl_get_tid_address(me, (int __user * __user *)arg2);
2431 : break;
2432 1 : case PR_SET_CHILD_SUBREAPER:
2433 1 : me->signal->is_child_subreaper = !!arg2;
2434 1 : if (!arg2)
2435 : break;
2436 :
2437 1 : walk_process_tree(me, propagate_has_child_subreaper, NULL);
2438 1 : break;
2439 0 : case PR_GET_CHILD_SUBREAPER:
2440 0 : error = put_user(me->signal->is_child_subreaper,
2441 : (int __user *)arg2);
2442 0 : break;
2443 151 : case PR_SET_NO_NEW_PRIVS:
2444 151 : if (arg2 != 1 || arg3 || arg4 || arg5)
2445 : return -EINVAL;
2446 :
2447 151 : task_set_no_new_privs(current);
2448 : break;
2449 0 : case PR_GET_NO_NEW_PRIVS:
2450 0 : if (arg2 || arg3 || arg4 || arg5)
2451 : return -EINVAL;
2452 0 : return task_no_new_privs(current) ? 1 : 0;
2453 0 : case PR_GET_THP_DISABLE:
2454 0 : if (arg2 || arg3 || arg4 || arg5)
2455 : return -EINVAL;
2456 0 : error = !!test_bit(MMF_DISABLE_THP, &me->mm->flags);
2457 0 : break;
2458 0 : case PR_SET_THP_DISABLE:
2459 0 : if (arg3 || arg4 || arg5)
2460 : return -EINVAL;
2461 0 : if (mmap_write_lock_killable(me->mm))
2462 : return -EINTR;
2463 0 : if (arg2)
2464 0 : set_bit(MMF_DISABLE_THP, &me->mm->flags);
2465 : else
2466 0 : clear_bit(MMF_DISABLE_THP, &me->mm->flags);
2467 0 : mmap_write_unlock(me->mm);
2468 0 : break;
2469 : case PR_MPX_ENABLE_MANAGEMENT:
2470 : case PR_MPX_DISABLE_MANAGEMENT:
2471 : /* No longer implemented: */
2472 : return -EINVAL;
2473 : case PR_SET_FP_MODE:
2474 : error = SET_FP_MODE(me, arg2);
2475 : break;
2476 : case PR_GET_FP_MODE:
2477 : error = GET_FP_MODE(me);
2478 : break;
2479 : case PR_SVE_SET_VL:
2480 : error = SVE_SET_VL(arg2);
2481 : break;
2482 : case PR_SVE_GET_VL:
2483 : error = SVE_GET_VL();
2484 : break;
2485 0 : case PR_GET_SPECULATION_CTRL:
2486 0 : if (arg3 || arg4 || arg5)
2487 : return -EINVAL;
2488 0 : error = arch_prctl_spec_ctrl_get(me, arg2);
2489 0 : break;
2490 0 : case PR_SET_SPECULATION_CTRL:
2491 0 : if (arg4 || arg5)
2492 : return -EINVAL;
2493 0 : error = arch_prctl_spec_ctrl_set(me, arg2, arg3);
2494 0 : break;
2495 0 : case PR_PAC_RESET_KEYS:
2496 0 : if (arg3 || arg4 || arg5)
2497 : return -EINVAL;
2498 : error = PAC_RESET_KEYS(me, arg2);
2499 : break;
2500 0 : case PR_SET_TAGGED_ADDR_CTRL:
2501 0 : if (arg3 || arg4 || arg5)
2502 : return -EINVAL;
2503 : error = SET_TAGGED_ADDR_CTRL(arg2);
2504 : break;
2505 0 : case PR_GET_TAGGED_ADDR_CTRL:
2506 0 : if (arg2 || arg3 || arg4 || arg5)
2507 : return -EINVAL;
2508 : error = GET_TAGGED_ADDR_CTRL();
2509 : break;
2510 0 : case PR_SET_IO_FLUSHER:
2511 0 : if (!capable(CAP_SYS_RESOURCE))
2512 : return -EPERM;
2513 :
2514 0 : if (arg3 || arg4 || arg5)
2515 : return -EINVAL;
2516 :
2517 0 : if (arg2 == 1)
2518 0 : current->flags |= PR_IO_FLUSHER;
2519 0 : else if (!arg2)
2520 0 : current->flags &= ~PR_IO_FLUSHER;
2521 : else
2522 : return -EINVAL;
2523 : break;
2524 0 : case PR_GET_IO_FLUSHER:
2525 0 : if (!capable(CAP_SYS_RESOURCE))
2526 : return -EPERM;
2527 :
2528 0 : if (arg2 || arg3 || arg4 || arg5)
2529 : return -EINVAL;
2530 :
2531 0 : error = (current->flags & PR_IO_FLUSHER) == PR_IO_FLUSHER;
2532 0 : break;
2533 0 : case PR_SET_SYSCALL_USER_DISPATCH:
2534 0 : error = set_syscall_user_dispatch(arg2, arg3, arg4,
2535 : (char __user *) arg5);
2536 0 : break;
2537 : default:
2538 : error = -EINVAL;
2539 : break;
2540 : }
2541 0 : return error;
2542 : }
2543 :
2544 0 : SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
2545 : struct getcpu_cache __user *, unused)
2546 : {
2547 0 : int err = 0;
2548 0 : int cpu = raw_smp_processor_id();
2549 :
2550 0 : if (cpup)
2551 0 : err |= put_user(cpu, cpup);
2552 0 : if (nodep)
2553 0 : err |= put_user(cpu_to_node(cpu), nodep);
2554 0 : return err ? -EFAULT : 0;
2555 : }
2556 :
2557 : /**
2558 : * do_sysinfo - fill in sysinfo struct
2559 : * @info: pointer to buffer to fill
2560 : */
2561 11 : static int do_sysinfo(struct sysinfo *info)
2562 : {
2563 11 : unsigned long mem_total, sav_total;
2564 11 : unsigned int mem_unit, bitcount;
2565 11 : struct timespec64 tp;
2566 :
2567 11 : memset(info, 0, sizeof(struct sysinfo));
2568 :
2569 11 : ktime_get_boottime_ts64(&tp);
2570 11 : timens_add_boottime(&tp);
2571 11 : info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0);
2572 :
2573 11 : get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT);
2574 :
2575 11 : info->procs = nr_threads;
2576 :
2577 11 : si_meminfo(info);
2578 11 : si_swapinfo(info);
2579 :
2580 : /*
2581 : * If the sum of all the available memory (i.e. ram + swap)
2582 : * is less than can be stored in a 32 bit unsigned long then
2583 : * we can be binary compatible with 2.2.x kernels. If not,
2584 : * well, in that case 2.2.x was broken anyways...
2585 : *
2586 : * -Erik Andersen <andersee@debian.org>
2587 : */
2588 :
2589 11 : mem_total = info->totalram + info->totalswap;
2590 11 : if (mem_total < info->totalram || mem_total < info->totalswap)
2591 : goto out;
2592 11 : bitcount = 0;
2593 11 : mem_unit = info->mem_unit;
2594 143 : while (mem_unit > 1) {
2595 132 : bitcount++;
2596 132 : mem_unit >>= 1;
2597 132 : sav_total = mem_total;
2598 132 : mem_total <<= 1;
2599 132 : if (mem_total < sav_total)
2600 0 : goto out;
2601 : }
2602 :
2603 : /*
2604 : * If mem_total did not overflow, multiply all memory values by
2605 : * info->mem_unit and set it to 1. This leaves things compatible
2606 : * with 2.2.x, and also retains compatibility with earlier 2.4.x
2607 : * kernels...
2608 : */
2609 :
2610 11 : info->mem_unit = 1;
2611 11 : info->totalram <<= bitcount;
2612 11 : info->freeram <<= bitcount;
2613 11 : info->sharedram <<= bitcount;
2614 11 : info->bufferram <<= bitcount;
2615 11 : info->totalswap <<= bitcount;
2616 11 : info->freeswap <<= bitcount;
2617 11 : info->totalhigh <<= bitcount;
2618 11 : info->freehigh <<= bitcount;
2619 :
2620 11 : out:
2621 11 : return 0;
2622 : }
2623 :
2624 22 : SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info)
2625 : {
2626 11 : struct sysinfo val;
2627 :
2628 11 : do_sysinfo(&val);
2629 :
2630 11 : if (copy_to_user(info, &val, sizeof(struct sysinfo)))
2631 0 : return -EFAULT;
2632 :
2633 : return 0;
2634 : }
2635 :
2636 : #ifdef CONFIG_COMPAT
2637 : struct compat_sysinfo {
2638 : s32 uptime;
2639 : u32 loads[3];
2640 : u32 totalram;
2641 : u32 freeram;
2642 : u32 sharedram;
2643 : u32 bufferram;
2644 : u32 totalswap;
2645 : u32 freeswap;
2646 : u16 procs;
2647 : u16 pad;
2648 : u32 totalhigh;
2649 : u32 freehigh;
2650 : u32 mem_unit;
2651 : char _f[20-2*sizeof(u32)-sizeof(int)];
2652 : };
2653 :
2654 0 : COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
2655 : {
2656 0 : struct sysinfo s;
2657 0 : struct compat_sysinfo s_32;
2658 :
2659 0 : do_sysinfo(&s);
2660 :
2661 : /* Check to see if any memory value is too large for 32-bit and scale
2662 : * down if needed
2663 : */
2664 0 : if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) {
2665 : int bitcount = 0;
2666 :
2667 0 : while (s.mem_unit < PAGE_SIZE) {
2668 0 : s.mem_unit <<= 1;
2669 0 : bitcount++;
2670 : }
2671 :
2672 0 : s.totalram >>= bitcount;
2673 0 : s.freeram >>= bitcount;
2674 0 : s.sharedram >>= bitcount;
2675 0 : s.bufferram >>= bitcount;
2676 0 : s.totalswap >>= bitcount;
2677 0 : s.freeswap >>= bitcount;
2678 0 : s.totalhigh >>= bitcount;
2679 0 : s.freehigh >>= bitcount;
2680 : }
2681 :
2682 0 : memset(&s_32, 0, sizeof(s_32));
2683 0 : s_32.uptime = s.uptime;
2684 0 : s_32.loads[0] = s.loads[0];
2685 0 : s_32.loads[1] = s.loads[1];
2686 0 : s_32.loads[2] = s.loads[2];
2687 0 : s_32.totalram = s.totalram;
2688 0 : s_32.freeram = s.freeram;
2689 0 : s_32.sharedram = s.sharedram;
2690 0 : s_32.bufferram = s.bufferram;
2691 0 : s_32.totalswap = s.totalswap;
2692 0 : s_32.freeswap = s.freeswap;
2693 0 : s_32.procs = s.procs;
2694 0 : s_32.totalhigh = s.totalhigh;
2695 0 : s_32.freehigh = s.freehigh;
2696 0 : s_32.mem_unit = s.mem_unit;
2697 0 : if (copy_to_user(info, &s_32, sizeof(s_32)))
2698 0 : return -EFAULT;
2699 : return 0;
2700 : }
2701 : #endif /* CONFIG_COMPAT */
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