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[linux/fpc-iii.git] / kernel / sys.c
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1 /*
2 * linux/kernel/sys.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
7 #include <linux/module.h>
8 #include <linux/mm.h>
9 #include <linux/utsname.h>
10 #include <linux/mman.h>
11 #include <linux/notifier.h>
12 #include <linux/reboot.h>
13 #include <linux/prctl.h>
14 #include <linux/highuid.h>
15 #include <linux/fs.h>
16 #include <linux/perf_event.h>
17 #include <linux/resource.h>
18 #include <linux/kernel.h>
19 #include <linux/kexec.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/dcookies.h>
28 #include <linux/suspend.h>
29 #include <linux/tty.h>
30 #include <linux/signal.h>
31 #include <linux/cn_proc.h>
32 #include <linux/getcpu.h>
33 #include <linux/task_io_accounting_ops.h>
34 #include <linux/seccomp.h>
35 #include <linux/cpu.h>
36 #include <linux/ptrace.h>
37 #include <linux/fs_struct.h>
39 #include <linux/compat.h>
40 #include <linux/syscalls.h>
41 #include <linux/kprobes.h>
42 #include <linux/user_namespace.h>
44 #include <asm/uaccess.h>
45 #include <asm/io.h>
46 #include <asm/unistd.h>
48 #ifndef SET_UNALIGN_CTL
49 # define SET_UNALIGN_CTL(a,b) (-EINVAL)
50 #endif
51 #ifndef GET_UNALIGN_CTL
52 # define GET_UNALIGN_CTL(a,b) (-EINVAL)
53 #endif
54 #ifndef SET_FPEMU_CTL
55 # define SET_FPEMU_CTL(a,b) (-EINVAL)
56 #endif
57 #ifndef GET_FPEMU_CTL
58 # define GET_FPEMU_CTL(a,b) (-EINVAL)
59 #endif
60 #ifndef SET_FPEXC_CTL
61 # define SET_FPEXC_CTL(a,b) (-EINVAL)
62 #endif
63 #ifndef GET_FPEXC_CTL
64 # define GET_FPEXC_CTL(a,b) (-EINVAL)
65 #endif
66 #ifndef GET_ENDIAN
67 # define GET_ENDIAN(a,b) (-EINVAL)
68 #endif
69 #ifndef SET_ENDIAN
70 # define SET_ENDIAN(a,b) (-EINVAL)
71 #endif
72 #ifndef GET_TSC_CTL
73 # define GET_TSC_CTL(a) (-EINVAL)
74 #endif
75 #ifndef SET_TSC_CTL
76 # define SET_TSC_CTL(a) (-EINVAL)
77 #endif
80 * this is where the system-wide overflow UID and GID are defined, for
81 * architectures that now have 32-bit UID/GID but didn't in the past
84 int overflowuid = DEFAULT_OVERFLOWUID;
85 int overflowgid = DEFAULT_OVERFLOWGID;
87 #ifdef CONFIG_UID16
88 EXPORT_SYMBOL(overflowuid);
89 EXPORT_SYMBOL(overflowgid);
90 #endif
93 * the same as above, but for filesystems which can only store a 16-bit
94 * UID and GID. as such, this is needed on all architectures
97 int fs_overflowuid = DEFAULT_FS_OVERFLOWUID;
98 int fs_overflowgid = DEFAULT_FS_OVERFLOWUID;
100 EXPORT_SYMBOL(fs_overflowuid);
101 EXPORT_SYMBOL(fs_overflowgid);
104 * this indicates whether you can reboot with ctrl-alt-del: the default is yes
107 int C_A_D = 1;
108 struct pid *cad_pid;
109 EXPORT_SYMBOL(cad_pid);
112 * If set, this is used for preparing the system to power off.
115 void (*pm_power_off_prepare)(void);
118 * set the priority of a task
119 * - the caller must hold the RCU read lock
121 static int set_one_prio(struct task_struct *p, int niceval, int error)
123 const struct cred *cred = current_cred(), *pcred = __task_cred(p);
124 int no_nice;
126 if (pcred->uid != cred->euid &&
127 pcred->euid != cred->euid && !capable(CAP_SYS_NICE)) {
128 error = -EPERM;
129 goto out;
131 if (niceval < task_nice(p) && !can_nice(p, niceval)) {
132 error = -EACCES;
133 goto out;
135 no_nice = security_task_setnice(p, niceval);
136 if (no_nice) {
137 error = no_nice;
138 goto out;
140 if (error == -ESRCH)
141 error = 0;
142 set_user_nice(p, niceval);
143 out:
144 return error;
147 SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
149 struct task_struct *g, *p;
150 struct user_struct *user;
151 const struct cred *cred = current_cred();
152 int error = -EINVAL;
153 struct pid *pgrp;
155 if (which > PRIO_USER || which < PRIO_PROCESS)
156 goto out;
158 /* normalize: avoid signed division (rounding problems) */
159 error = -ESRCH;
160 if (niceval < -20)
161 niceval = -20;
162 if (niceval > 19)
163 niceval = 19;
165 read_lock(&tasklist_lock);
166 switch (which) {
167 case PRIO_PROCESS:
168 if (who)
169 p = find_task_by_vpid(who);
170 else
171 p = current;
172 if (p)
173 error = set_one_prio(p, niceval, error);
174 break;
175 case PRIO_PGRP:
176 if (who)
177 pgrp = find_vpid(who);
178 else
179 pgrp = task_pgrp(current);
180 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
181 error = set_one_prio(p, niceval, error);
182 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
183 break;
184 case PRIO_USER:
185 user = (struct user_struct *) cred->user;
186 if (!who)
187 who = cred->uid;
188 else if ((who != cred->uid) &&
189 !(user = find_user(who)))
190 goto out_unlock; /* No processes for this user */
192 do_each_thread(g, p) {
193 if (__task_cred(p)->uid == who)
194 error = set_one_prio(p, niceval, error);
195 } while_each_thread(g, p);
196 if (who != cred->uid)
197 free_uid(user); /* For find_user() */
198 break;
200 out_unlock:
201 read_unlock(&tasklist_lock);
202 out:
203 return error;
207 * Ugh. To avoid negative return values, "getpriority()" will
208 * not return the normal nice-value, but a negated value that
209 * has been offset by 20 (ie it returns 40..1 instead of -20..19)
210 * to stay compatible.
212 SYSCALL_DEFINE2(getpriority, int, which, int, who)
214 struct task_struct *g, *p;
215 struct user_struct *user;
216 const struct cred *cred = current_cred();
217 long niceval, retval = -ESRCH;
218 struct pid *pgrp;
220 if (which > PRIO_USER || which < PRIO_PROCESS)
221 return -EINVAL;
223 read_lock(&tasklist_lock);
224 switch (which) {
225 case PRIO_PROCESS:
226 if (who)
227 p = find_task_by_vpid(who);
228 else
229 p = current;
230 if (p) {
231 niceval = 20 - task_nice(p);
232 if (niceval > retval)
233 retval = niceval;
235 break;
236 case PRIO_PGRP:
237 if (who)
238 pgrp = find_vpid(who);
239 else
240 pgrp = task_pgrp(current);
241 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
242 niceval = 20 - task_nice(p);
243 if (niceval > retval)
244 retval = niceval;
245 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
246 break;
247 case PRIO_USER:
248 user = (struct user_struct *) cred->user;
249 if (!who)
250 who = cred->uid;
251 else if ((who != cred->uid) &&
252 !(user = find_user(who)))
253 goto out_unlock; /* No processes for this user */
255 do_each_thread(g, p) {
256 if (__task_cred(p)->uid == who) {
257 niceval = 20 - task_nice(p);
258 if (niceval > retval)
259 retval = niceval;
261 } while_each_thread(g, p);
262 if (who != cred->uid)
263 free_uid(user); /* for find_user() */
264 break;
266 out_unlock:
267 read_unlock(&tasklist_lock);
269 return retval;
273 * emergency_restart - reboot the system
275 * Without shutting down any hardware or taking any locks
276 * reboot the system. This is called when we know we are in
277 * trouble so this is our best effort to reboot. This is
278 * safe to call in interrupt context.
280 void emergency_restart(void)
282 machine_emergency_restart();
284 EXPORT_SYMBOL_GPL(emergency_restart);
286 void kernel_restart_prepare(char *cmd)
288 blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd);
289 system_state = SYSTEM_RESTART;
290 device_shutdown();
291 sysdev_shutdown();
295 * kernel_restart - reboot the system
296 * @cmd: pointer to buffer containing command to execute for restart
297 * or %NULL
299 * Shutdown everything and perform a clean reboot.
300 * This is not safe to call in interrupt context.
302 void kernel_restart(char *cmd)
304 kernel_restart_prepare(cmd);
305 if (!cmd)
306 printk(KERN_EMERG "Restarting system.\n");
307 else
308 printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd);
309 machine_restart(cmd);
311 EXPORT_SYMBOL_GPL(kernel_restart);
313 static void kernel_shutdown_prepare(enum system_states state)
315 blocking_notifier_call_chain(&reboot_notifier_list,
316 (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL);
317 system_state = state;
318 device_shutdown();
321 * kernel_halt - halt the system
323 * Shutdown everything and perform a clean system halt.
325 void kernel_halt(void)
327 kernel_shutdown_prepare(SYSTEM_HALT);
328 sysdev_shutdown();
329 printk(KERN_EMERG "System halted.\n");
330 machine_halt();
333 EXPORT_SYMBOL_GPL(kernel_halt);
336 * kernel_power_off - power_off the system
338 * Shutdown everything and perform a clean system power_off.
340 void kernel_power_off(void)
342 kernel_shutdown_prepare(SYSTEM_POWER_OFF);
343 if (pm_power_off_prepare)
344 pm_power_off_prepare();
345 disable_nonboot_cpus();
346 sysdev_shutdown();
347 printk(KERN_EMERG "Power down.\n");
348 machine_power_off();
350 EXPORT_SYMBOL_GPL(kernel_power_off);
352 static DEFINE_MUTEX(reboot_mutex);
355 * Reboot system call: for obvious reasons only root may call it,
356 * and even root needs to set up some magic numbers in the registers
357 * so that some mistake won't make this reboot the whole machine.
358 * You can also set the meaning of the ctrl-alt-del-key here.
360 * reboot doesn't sync: do that yourself before calling this.
362 SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
363 void __user *, arg)
365 char buffer[256];
366 int ret = 0;
368 /* We only trust the superuser with rebooting the system. */
369 if (!capable(CAP_SYS_BOOT))
370 return -EPERM;
372 /* For safety, we require "magic" arguments. */
373 if (magic1 != LINUX_REBOOT_MAGIC1 ||
374 (magic2 != LINUX_REBOOT_MAGIC2 &&
375 magic2 != LINUX_REBOOT_MAGIC2A &&
376 magic2 != LINUX_REBOOT_MAGIC2B &&
377 magic2 != LINUX_REBOOT_MAGIC2C))
378 return -EINVAL;
380 /* Instead of trying to make the power_off code look like
381 * halt when pm_power_off is not set do it the easy way.
383 if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off)
384 cmd = LINUX_REBOOT_CMD_HALT;
386 mutex_lock(&reboot_mutex);
387 switch (cmd) {
388 case LINUX_REBOOT_CMD_RESTART:
389 kernel_restart(NULL);
390 break;
392 case LINUX_REBOOT_CMD_CAD_ON:
393 C_A_D = 1;
394 break;
396 case LINUX_REBOOT_CMD_CAD_OFF:
397 C_A_D = 0;
398 break;
400 case LINUX_REBOOT_CMD_HALT:
401 kernel_halt();
402 do_exit(0);
403 panic("cannot halt");
405 case LINUX_REBOOT_CMD_POWER_OFF:
406 kernel_power_off();
407 do_exit(0);
408 break;
410 case LINUX_REBOOT_CMD_RESTART2:
411 if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) {
412 ret = -EFAULT;
413 break;
415 buffer[sizeof(buffer) - 1] = '\0';
417 kernel_restart(buffer);
418 break;
420 #ifdef CONFIG_KEXEC
421 case LINUX_REBOOT_CMD_KEXEC:
422 ret = kernel_kexec();
423 break;
424 #endif
426 #ifdef CONFIG_HIBERNATION
427 case LINUX_REBOOT_CMD_SW_SUSPEND:
428 ret = hibernate();
429 break;
430 #endif
432 default:
433 ret = -EINVAL;
434 break;
436 mutex_unlock(&reboot_mutex);
437 return ret;
440 static void deferred_cad(struct work_struct *dummy)
442 kernel_restart(NULL);
446 * This function gets called by ctrl-alt-del - ie the keyboard interrupt.
447 * As it's called within an interrupt, it may NOT sync: the only choice
448 * is whether to reboot at once, or just ignore the ctrl-alt-del.
450 void ctrl_alt_del(void)
452 static DECLARE_WORK(cad_work, deferred_cad);
454 if (C_A_D)
455 schedule_work(&cad_work);
456 else
457 kill_cad_pid(SIGINT, 1);
461 * Unprivileged users may change the real gid to the effective gid
462 * or vice versa. (BSD-style)
464 * If you set the real gid at all, or set the effective gid to a value not
465 * equal to the real gid, then the saved gid is set to the new effective gid.
467 * This makes it possible for a setgid program to completely drop its
468 * privileges, which is often a useful assertion to make when you are doing
469 * a security audit over a program.
471 * The general idea is that a program which uses just setregid() will be
472 * 100% compatible with BSD. A program which uses just setgid() will be
473 * 100% compatible with POSIX with saved IDs.
475 * SMP: There are not races, the GIDs are checked only by filesystem
476 * operations (as far as semantic preservation is concerned).
478 SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
480 const struct cred *old;
481 struct cred *new;
482 int retval;
484 new = prepare_creds();
485 if (!new)
486 return -ENOMEM;
487 old = current_cred();
489 retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE);
490 if (retval)
491 goto error;
493 retval = -EPERM;
494 if (rgid != (gid_t) -1) {
495 if (old->gid == rgid ||
496 old->egid == rgid ||
497 capable(CAP_SETGID))
498 new->gid = rgid;
499 else
500 goto error;
502 if (egid != (gid_t) -1) {
503 if (old->gid == egid ||
504 old->egid == egid ||
505 old->sgid == egid ||
506 capable(CAP_SETGID))
507 new->egid = egid;
508 else
509 goto error;
512 if (rgid != (gid_t) -1 ||
513 (egid != (gid_t) -1 && egid != old->gid))
514 new->sgid = new->egid;
515 new->fsgid = new->egid;
517 return commit_creds(new);
519 error:
520 abort_creds(new);
521 return retval;
525 * setgid() is implemented like SysV w/ SAVED_IDS
527 * SMP: Same implicit races as above.
529 SYSCALL_DEFINE1(setgid, gid_t, gid)
531 const struct cred *old;
532 struct cred *new;
533 int retval;
535 new = prepare_creds();
536 if (!new)
537 return -ENOMEM;
538 old = current_cred();
540 retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID);
541 if (retval)
542 goto error;
544 retval = -EPERM;
545 if (capable(CAP_SETGID))
546 new->gid = new->egid = new->sgid = new->fsgid = gid;
547 else if (gid == old->gid || gid == old->sgid)
548 new->egid = new->fsgid = gid;
549 else
550 goto error;
552 return commit_creds(new);
554 error:
555 abort_creds(new);
556 return retval;
560 * change the user struct in a credentials set to match the new UID
562 static int set_user(struct cred *new)
564 struct user_struct *new_user;
566 new_user = alloc_uid(current_user_ns(), new->uid);
567 if (!new_user)
568 return -EAGAIN;
570 if (!task_can_switch_user(new_user, current)) {
571 free_uid(new_user);
572 return -EINVAL;
575 if (atomic_read(&new_user->processes) >=
576 current->signal->rlim[RLIMIT_NPROC].rlim_cur &&
577 new_user != INIT_USER) {
578 free_uid(new_user);
579 return -EAGAIN;
582 free_uid(new->user);
583 new->user = new_user;
584 return 0;
588 * Unprivileged users may change the real uid to the effective uid
589 * or vice versa. (BSD-style)
591 * If you set the real uid at all, or set the effective uid to a value not
592 * equal to the real uid, then the saved uid is set to the new effective uid.
594 * This makes it possible for a setuid program to completely drop its
595 * privileges, which is often a useful assertion to make when you are doing
596 * a security audit over a program.
598 * The general idea is that a program which uses just setreuid() will be
599 * 100% compatible with BSD. A program which uses just setuid() will be
600 * 100% compatible with POSIX with saved IDs.
602 SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
604 const struct cred *old;
605 struct cred *new;
606 int retval;
608 new = prepare_creds();
609 if (!new)
610 return -ENOMEM;
611 old = current_cred();
613 retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE);
614 if (retval)
615 goto error;
617 retval = -EPERM;
618 if (ruid != (uid_t) -1) {
619 new->uid = ruid;
620 if (old->uid != ruid &&
621 old->euid != ruid &&
622 !capable(CAP_SETUID))
623 goto error;
626 if (euid != (uid_t) -1) {
627 new->euid = euid;
628 if (old->uid != euid &&
629 old->euid != euid &&
630 old->suid != euid &&
631 !capable(CAP_SETUID))
632 goto error;
635 if (new->uid != old->uid) {
636 retval = set_user(new);
637 if (retval < 0)
638 goto error;
640 if (ruid != (uid_t) -1 ||
641 (euid != (uid_t) -1 && euid != old->uid))
642 new->suid = new->euid;
643 new->fsuid = new->euid;
645 retval = security_task_fix_setuid(new, old, LSM_SETID_RE);
646 if (retval < 0)
647 goto error;
649 return commit_creds(new);
651 error:
652 abort_creds(new);
653 return retval;
657 * setuid() is implemented like SysV with SAVED_IDS
659 * Note that SAVED_ID's is deficient in that a setuid root program
660 * like sendmail, for example, cannot set its uid to be a normal
661 * user and then switch back, because if you're root, setuid() sets
662 * the saved uid too. If you don't like this, blame the bright people
663 * in the POSIX committee and/or USG. Note that the BSD-style setreuid()
664 * will allow a root program to temporarily drop privileges and be able to
665 * regain them by swapping the real and effective uid.
667 SYSCALL_DEFINE1(setuid, uid_t, uid)
669 const struct cred *old;
670 struct cred *new;
671 int retval;
673 new = prepare_creds();
674 if (!new)
675 return -ENOMEM;
676 old = current_cred();
678 retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID);
679 if (retval)
680 goto error;
682 retval = -EPERM;
683 if (capable(CAP_SETUID)) {
684 new->suid = new->uid = uid;
685 if (uid != old->uid) {
686 retval = set_user(new);
687 if (retval < 0)
688 goto error;
690 } else if (uid != old->uid && uid != new->suid) {
691 goto error;
694 new->fsuid = new->euid = uid;
696 retval = security_task_fix_setuid(new, old, LSM_SETID_ID);
697 if (retval < 0)
698 goto error;
700 return commit_creds(new);
702 error:
703 abort_creds(new);
704 return retval;
709 * This function implements a generic ability to update ruid, euid,
710 * and suid. This allows you to implement the 4.4 compatible seteuid().
712 SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid)
714 const struct cred *old;
715 struct cred *new;
716 int retval;
718 new = prepare_creds();
719 if (!new)
720 return -ENOMEM;
722 retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES);
723 if (retval)
724 goto error;
725 old = current_cred();
727 retval = -EPERM;
728 if (!capable(CAP_SETUID)) {
729 if (ruid != (uid_t) -1 && ruid != old->uid &&
730 ruid != old->euid && ruid != old->suid)
731 goto error;
732 if (euid != (uid_t) -1 && euid != old->uid &&
733 euid != old->euid && euid != old->suid)
734 goto error;
735 if (suid != (uid_t) -1 && suid != old->uid &&
736 suid != old->euid && suid != old->suid)
737 goto error;
740 if (ruid != (uid_t) -1) {
741 new->uid = ruid;
742 if (ruid != old->uid) {
743 retval = set_user(new);
744 if (retval < 0)
745 goto error;
748 if (euid != (uid_t) -1)
749 new->euid = euid;
750 if (suid != (uid_t) -1)
751 new->suid = suid;
752 new->fsuid = new->euid;
754 retval = security_task_fix_setuid(new, old, LSM_SETID_RES);
755 if (retval < 0)
756 goto error;
758 return commit_creds(new);
760 error:
761 abort_creds(new);
762 return retval;
765 SYSCALL_DEFINE3(getresuid, uid_t __user *, ruid, uid_t __user *, euid, uid_t __user *, suid)
767 const struct cred *cred = current_cred();
768 int retval;
770 if (!(retval = put_user(cred->uid, ruid)) &&
771 !(retval = put_user(cred->euid, euid)))
772 retval = put_user(cred->suid, suid);
774 return retval;
778 * Same as above, but for rgid, egid, sgid.
780 SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid)
782 const struct cred *old;
783 struct cred *new;
784 int retval;
786 new = prepare_creds();
787 if (!new)
788 return -ENOMEM;
789 old = current_cred();
791 retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES);
792 if (retval)
793 goto error;
795 retval = -EPERM;
796 if (!capable(CAP_SETGID)) {
797 if (rgid != (gid_t) -1 && rgid != old->gid &&
798 rgid != old->egid && rgid != old->sgid)
799 goto error;
800 if (egid != (gid_t) -1 && egid != old->gid &&
801 egid != old->egid && egid != old->sgid)
802 goto error;
803 if (sgid != (gid_t) -1 && sgid != old->gid &&
804 sgid != old->egid && sgid != old->sgid)
805 goto error;
808 if (rgid != (gid_t) -1)
809 new->gid = rgid;
810 if (egid != (gid_t) -1)
811 new->egid = egid;
812 if (sgid != (gid_t) -1)
813 new->sgid = sgid;
814 new->fsgid = new->egid;
816 return commit_creds(new);
818 error:
819 abort_creds(new);
820 return retval;
823 SYSCALL_DEFINE3(getresgid, gid_t __user *, rgid, gid_t __user *, egid, gid_t __user *, sgid)
825 const struct cred *cred = current_cred();
826 int retval;
828 if (!(retval = put_user(cred->gid, rgid)) &&
829 !(retval = put_user(cred->egid, egid)))
830 retval = put_user(cred->sgid, sgid);
832 return retval;
837 * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This
838 * is used for "access()" and for the NFS daemon (letting nfsd stay at
839 * whatever uid it wants to). It normally shadows "euid", except when
840 * explicitly set by setfsuid() or for access..
842 SYSCALL_DEFINE1(setfsuid, uid_t, uid)
844 const struct cred *old;
845 struct cred *new;
846 uid_t old_fsuid;
848 new = prepare_creds();
849 if (!new)
850 return current_fsuid();
851 old = current_cred();
852 old_fsuid = old->fsuid;
854 if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS) < 0)
855 goto error;
857 if (uid == old->uid || uid == old->euid ||
858 uid == old->suid || uid == old->fsuid ||
859 capable(CAP_SETUID)) {
860 if (uid != old_fsuid) {
861 new->fsuid = uid;
862 if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0)
863 goto change_okay;
867 error:
868 abort_creds(new);
869 return old_fsuid;
871 change_okay:
872 commit_creds(new);
873 return old_fsuid;
877 * Samma på svenska..
879 SYSCALL_DEFINE1(setfsgid, gid_t, gid)
881 const struct cred *old;
882 struct cred *new;
883 gid_t old_fsgid;
885 new = prepare_creds();
886 if (!new)
887 return current_fsgid();
888 old = current_cred();
889 old_fsgid = old->fsgid;
891 if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS))
892 goto error;
894 if (gid == old->gid || gid == old->egid ||
895 gid == old->sgid || gid == old->fsgid ||
896 capable(CAP_SETGID)) {
897 if (gid != old_fsgid) {
898 new->fsgid = gid;
899 goto change_okay;
903 error:
904 abort_creds(new);
905 return old_fsgid;
907 change_okay:
908 commit_creds(new);
909 return old_fsgid;
912 void do_sys_times(struct tms *tms)
914 cputime_t tgutime, tgstime, cutime, cstime;
916 spin_lock_irq(&current->sighand->siglock);
917 thread_group_times(current, &tgutime, &tgstime);
918 cutime = current->signal->cutime;
919 cstime = current->signal->cstime;
920 spin_unlock_irq(&current->sighand->siglock);
921 tms->tms_utime = cputime_to_clock_t(tgutime);
922 tms->tms_stime = cputime_to_clock_t(tgstime);
923 tms->tms_cutime = cputime_to_clock_t(cutime);
924 tms->tms_cstime = cputime_to_clock_t(cstime);
927 SYSCALL_DEFINE1(times, struct tms __user *, tbuf)
929 if (tbuf) {
930 struct tms tmp;
932 do_sys_times(&tmp);
933 if (copy_to_user(tbuf, &tmp, sizeof(struct tms)))
934 return -EFAULT;
936 force_successful_syscall_return();
937 return (long) jiffies_64_to_clock_t(get_jiffies_64());
941 * This needs some heavy checking ...
942 * I just haven't the stomach for it. I also don't fully
943 * understand sessions/pgrp etc. Let somebody who does explain it.
945 * OK, I think I have the protection semantics right.... this is really
946 * only important on a multi-user system anyway, to make sure one user
947 * can't send a signal to a process owned by another. -TYT, 12/12/91
949 * Auch. Had to add the 'did_exec' flag to conform completely to POSIX.
950 * LBT 04.03.94
952 SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid)
954 struct task_struct *p;
955 struct task_struct *group_leader = current->group_leader;
956 struct pid *pgrp;
957 int err;
959 if (!pid)
960 pid = task_pid_vnr(group_leader);
961 if (!pgid)
962 pgid = pid;
963 if (pgid < 0)
964 return -EINVAL;
966 /* From this point forward we keep holding onto the tasklist lock
967 * so that our parent does not change from under us. -DaveM
969 write_lock_irq(&tasklist_lock);
971 err = -ESRCH;
972 p = find_task_by_vpid(pid);
973 if (!p)
974 goto out;
976 err = -EINVAL;
977 if (!thread_group_leader(p))
978 goto out;
980 if (same_thread_group(p->real_parent, group_leader)) {
981 err = -EPERM;
982 if (task_session(p) != task_session(group_leader))
983 goto out;
984 err = -EACCES;
985 if (p->did_exec)
986 goto out;
987 } else {
988 err = -ESRCH;
989 if (p != group_leader)
990 goto out;
993 err = -EPERM;
994 if (p->signal->leader)
995 goto out;
997 pgrp = task_pid(p);
998 if (pgid != pid) {
999 struct task_struct *g;
1001 pgrp = find_vpid(pgid);
1002 g = pid_task(pgrp, PIDTYPE_PGID);
1003 if (!g || task_session(g) != task_session(group_leader))
1004 goto out;
1007 err = security_task_setpgid(p, pgid);
1008 if (err)
1009 goto out;
1011 if (task_pgrp(p) != pgrp)
1012 change_pid(p, PIDTYPE_PGID, pgrp);
1014 err = 0;
1015 out:
1016 /* All paths lead to here, thus we are safe. -DaveM */
1017 write_unlock_irq(&tasklist_lock);
1018 return err;
1021 SYSCALL_DEFINE1(getpgid, pid_t, pid)
1023 struct task_struct *p;
1024 struct pid *grp;
1025 int retval;
1027 rcu_read_lock();
1028 if (!pid)
1029 grp = task_pgrp(current);
1030 else {
1031 retval = -ESRCH;
1032 p = find_task_by_vpid(pid);
1033 if (!p)
1034 goto out;
1035 grp = task_pgrp(p);
1036 if (!grp)
1037 goto out;
1039 retval = security_task_getpgid(p);
1040 if (retval)
1041 goto out;
1043 retval = pid_vnr(grp);
1044 out:
1045 rcu_read_unlock();
1046 return retval;
1049 #ifdef __ARCH_WANT_SYS_GETPGRP
1051 SYSCALL_DEFINE0(getpgrp)
1053 return sys_getpgid(0);
1056 #endif
1058 SYSCALL_DEFINE1(getsid, pid_t, pid)
1060 struct task_struct *p;
1061 struct pid *sid;
1062 int retval;
1064 rcu_read_lock();
1065 if (!pid)
1066 sid = task_session(current);
1067 else {
1068 retval = -ESRCH;
1069 p = find_task_by_vpid(pid);
1070 if (!p)
1071 goto out;
1072 sid = task_session(p);
1073 if (!sid)
1074 goto out;
1076 retval = security_task_getsid(p);
1077 if (retval)
1078 goto out;
1080 retval = pid_vnr(sid);
1081 out:
1082 rcu_read_unlock();
1083 return retval;
1086 SYSCALL_DEFINE0(setsid)
1088 struct task_struct *group_leader = current->group_leader;
1089 struct pid *sid = task_pid(group_leader);
1090 pid_t session = pid_vnr(sid);
1091 int err = -EPERM;
1093 write_lock_irq(&tasklist_lock);
1094 /* Fail if I am already a session leader */
1095 if (group_leader->signal->leader)
1096 goto out;
1098 /* Fail if a process group id already exists that equals the
1099 * proposed session id.
1101 if (pid_task(sid, PIDTYPE_PGID))
1102 goto out;
1104 group_leader->signal->leader = 1;
1105 __set_special_pids(sid);
1107 proc_clear_tty(group_leader);
1109 err = session;
1110 out:
1111 write_unlock_irq(&tasklist_lock);
1112 if (err > 0)
1113 proc_sid_connector(group_leader);
1114 return err;
1117 DECLARE_RWSEM(uts_sem);
1119 SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
1121 int errno = 0;
1123 down_read(&uts_sem);
1124 if (copy_to_user(name, utsname(), sizeof *name))
1125 errno = -EFAULT;
1126 up_read(&uts_sem);
1127 return errno;
1130 SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
1132 int errno;
1133 char tmp[__NEW_UTS_LEN];
1135 if (!capable(CAP_SYS_ADMIN))
1136 return -EPERM;
1137 if (len < 0 || len > __NEW_UTS_LEN)
1138 return -EINVAL;
1139 down_write(&uts_sem);
1140 errno = -EFAULT;
1141 if (!copy_from_user(tmp, name, len)) {
1142 struct new_utsname *u = utsname();
1144 memcpy(u->nodename, tmp, len);
1145 memset(u->nodename + len, 0, sizeof(u->nodename) - len);
1146 errno = 0;
1148 up_write(&uts_sem);
1149 return errno;
1152 #ifdef __ARCH_WANT_SYS_GETHOSTNAME
1154 SYSCALL_DEFINE2(gethostname, char __user *, name, int, len)
1156 int i, errno;
1157 struct new_utsname *u;
1159 if (len < 0)
1160 return -EINVAL;
1161 down_read(&uts_sem);
1162 u = utsname();
1163 i = 1 + strlen(u->nodename);
1164 if (i > len)
1165 i = len;
1166 errno = 0;
1167 if (copy_to_user(name, u->nodename, i))
1168 errno = -EFAULT;
1169 up_read(&uts_sem);
1170 return errno;
1173 #endif
1176 * Only setdomainname; getdomainname can be implemented by calling
1177 * uname()
1179 SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len)
1181 int errno;
1182 char tmp[__NEW_UTS_LEN];
1184 if (!capable(CAP_SYS_ADMIN))
1185 return -EPERM;
1186 if (len < 0 || len > __NEW_UTS_LEN)
1187 return -EINVAL;
1189 down_write(&uts_sem);
1190 errno = -EFAULT;
1191 if (!copy_from_user(tmp, name, len)) {
1192 struct new_utsname *u = utsname();
1194 memcpy(u->domainname, tmp, len);
1195 memset(u->domainname + len, 0, sizeof(u->domainname) - len);
1196 errno = 0;
1198 up_write(&uts_sem);
1199 return errno;
1202 SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1204 if (resource >= RLIM_NLIMITS)
1205 return -EINVAL;
1206 else {
1207 struct rlimit value;
1208 task_lock(current->group_leader);
1209 value = current->signal->rlim[resource];
1210 task_unlock(current->group_leader);
1211 return copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0;
1215 #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
1218 * Back compatibility for getrlimit. Needed for some apps.
1221 SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1222 struct rlimit __user *, rlim)
1224 struct rlimit x;
1225 if (resource >= RLIM_NLIMITS)
1226 return -EINVAL;
1228 task_lock(current->group_leader);
1229 x = current->signal->rlim[resource];
1230 task_unlock(current->group_leader);
1231 if (x.rlim_cur > 0x7FFFFFFF)
1232 x.rlim_cur = 0x7FFFFFFF;
1233 if (x.rlim_max > 0x7FFFFFFF)
1234 x.rlim_max = 0x7FFFFFFF;
1235 return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0;
1238 #endif
1240 SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1242 struct rlimit new_rlim, *old_rlim;
1243 int retval;
1245 if (resource >= RLIM_NLIMITS)
1246 return -EINVAL;
1247 if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
1248 return -EFAULT;
1249 if (new_rlim.rlim_cur > new_rlim.rlim_max)
1250 return -EINVAL;
1251 old_rlim = current->signal->rlim + resource;
1252 if ((new_rlim.rlim_max > old_rlim->rlim_max) &&
1253 !capable(CAP_SYS_RESOURCE))
1254 return -EPERM;
1255 if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open)
1256 return -EPERM;
1258 retval = security_task_setrlimit(resource, &new_rlim);
1259 if (retval)
1260 return retval;
1262 if (resource == RLIMIT_CPU && new_rlim.rlim_cur == 0) {
1264 * The caller is asking for an immediate RLIMIT_CPU
1265 * expiry. But we use the zero value to mean "it was
1266 * never set". So let's cheat and make it one second
1267 * instead
1269 new_rlim.rlim_cur = 1;
1272 task_lock(current->group_leader);
1273 *old_rlim = new_rlim;
1274 task_unlock(current->group_leader);
1276 if (resource != RLIMIT_CPU)
1277 goto out;
1280 * RLIMIT_CPU handling. Note that the kernel fails to return an error
1281 * code if it rejected the user's attempt to set RLIMIT_CPU. This is a
1282 * very long-standing error, and fixing it now risks breakage of
1283 * applications, so we live with it
1285 if (new_rlim.rlim_cur == RLIM_INFINITY)
1286 goto out;
1288 update_rlimit_cpu(new_rlim.rlim_cur);
1289 out:
1290 return 0;
1294 * It would make sense to put struct rusage in the task_struct,
1295 * except that would make the task_struct be *really big*. After
1296 * task_struct gets moved into malloc'ed memory, it would
1297 * make sense to do this. It will make moving the rest of the information
1298 * a lot simpler! (Which we're not doing right now because we're not
1299 * measuring them yet).
1301 * When sampling multiple threads for RUSAGE_SELF, under SMP we might have
1302 * races with threads incrementing their own counters. But since word
1303 * reads are atomic, we either get new values or old values and we don't
1304 * care which for the sums. We always take the siglock to protect reading
1305 * the c* fields from p->signal from races with exit.c updating those
1306 * fields when reaping, so a sample either gets all the additions of a
1307 * given child after it's reaped, or none so this sample is before reaping.
1309 * Locking:
1310 * We need to take the siglock for CHILDEREN, SELF and BOTH
1311 * for the cases current multithreaded, non-current single threaded
1312 * non-current multithreaded. Thread traversal is now safe with
1313 * the siglock held.
1314 * Strictly speaking, we donot need to take the siglock if we are current and
1315 * single threaded, as no one else can take our signal_struct away, no one
1316 * else can reap the children to update signal->c* counters, and no one else
1317 * can race with the signal-> fields. If we do not take any lock, the
1318 * signal-> fields could be read out of order while another thread was just
1319 * exiting. So we should place a read memory barrier when we avoid the lock.
1320 * On the writer side, write memory barrier is implied in __exit_signal
1321 * as __exit_signal releases the siglock spinlock after updating the signal->
1322 * fields. But we don't do this yet to keep things simple.
1326 static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r)
1328 r->ru_nvcsw += t->nvcsw;
1329 r->ru_nivcsw += t->nivcsw;
1330 r->ru_minflt += t->min_flt;
1331 r->ru_majflt += t->maj_flt;
1332 r->ru_inblock += task_io_get_inblock(t);
1333 r->ru_oublock += task_io_get_oublock(t);
1336 static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
1338 struct task_struct *t;
1339 unsigned long flags;
1340 cputime_t tgutime, tgstime, utime, stime;
1341 unsigned long maxrss = 0;
1343 memset((char *) r, 0, sizeof *r);
1344 utime = stime = cputime_zero;
1346 if (who == RUSAGE_THREAD) {
1347 task_times(current, &utime, &stime);
1348 accumulate_thread_rusage(p, r);
1349 maxrss = p->signal->maxrss;
1350 goto out;
1353 if (!lock_task_sighand(p, &flags))
1354 return;
1356 switch (who) {
1357 case RUSAGE_BOTH:
1358 case RUSAGE_CHILDREN:
1359 utime = p->signal->cutime;
1360 stime = p->signal->cstime;
1361 r->ru_nvcsw = p->signal->cnvcsw;
1362 r->ru_nivcsw = p->signal->cnivcsw;
1363 r->ru_minflt = p->signal->cmin_flt;
1364 r->ru_majflt = p->signal->cmaj_flt;
1365 r->ru_inblock = p->signal->cinblock;
1366 r->ru_oublock = p->signal->coublock;
1367 maxrss = p->signal->cmaxrss;
1369 if (who == RUSAGE_CHILDREN)
1370 break;
1372 case RUSAGE_SELF:
1373 thread_group_times(p, &tgutime, &tgstime);
1374 utime = cputime_add(utime, tgutime);
1375 stime = cputime_add(stime, tgstime);
1376 r->ru_nvcsw += p->signal->nvcsw;
1377 r->ru_nivcsw += p->signal->nivcsw;
1378 r->ru_minflt += p->signal->min_flt;
1379 r->ru_majflt += p->signal->maj_flt;
1380 r->ru_inblock += p->signal->inblock;
1381 r->ru_oublock += p->signal->oublock;
1382 if (maxrss < p->signal->maxrss)
1383 maxrss = p->signal->maxrss;
1384 t = p;
1385 do {
1386 accumulate_thread_rusage(t, r);
1387 t = next_thread(t);
1388 } while (t != p);
1389 break;
1391 default:
1392 BUG();
1394 unlock_task_sighand(p, &flags);
1396 out:
1397 cputime_to_timeval(utime, &r->ru_utime);
1398 cputime_to_timeval(stime, &r->ru_stime);
1400 if (who != RUSAGE_CHILDREN) {
1401 struct mm_struct *mm = get_task_mm(p);
1402 if (mm) {
1403 setmax_mm_hiwater_rss(&maxrss, mm);
1404 mmput(mm);
1407 r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */
1410 int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
1412 struct rusage r;
1413 k_getrusage(p, who, &r);
1414 return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
1417 SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru)
1419 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1420 who != RUSAGE_THREAD)
1421 return -EINVAL;
1422 return getrusage(current, who, ru);
1425 SYSCALL_DEFINE1(umask, int, mask)
1427 mask = xchg(&current->fs->umask, mask & S_IRWXUGO);
1428 return mask;
1431 SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
1432 unsigned long, arg4, unsigned long, arg5)
1434 struct task_struct *me = current;
1435 unsigned char comm[sizeof(me->comm)];
1436 long error;
1438 error = security_task_prctl(option, arg2, arg3, arg4, arg5);
1439 if (error != -ENOSYS)
1440 return error;
1442 error = 0;
1443 switch (option) {
1444 case PR_SET_PDEATHSIG:
1445 if (!valid_signal(arg2)) {
1446 error = -EINVAL;
1447 break;
1449 me->pdeath_signal = arg2;
1450 error = 0;
1451 break;
1452 case PR_GET_PDEATHSIG:
1453 error = put_user(me->pdeath_signal, (int __user *)arg2);
1454 break;
1455 case PR_GET_DUMPABLE:
1456 error = get_dumpable(me->mm);
1457 break;
1458 case PR_SET_DUMPABLE:
1459 if (arg2 < 0 || arg2 > 1) {
1460 error = -EINVAL;
1461 break;
1463 set_dumpable(me->mm, arg2);
1464 error = 0;
1465 break;
1467 case PR_SET_UNALIGN:
1468 error = SET_UNALIGN_CTL(me, arg2);
1469 break;
1470 case PR_GET_UNALIGN:
1471 error = GET_UNALIGN_CTL(me, arg2);
1472 break;
1473 case PR_SET_FPEMU:
1474 error = SET_FPEMU_CTL(me, arg2);
1475 break;
1476 case PR_GET_FPEMU:
1477 error = GET_FPEMU_CTL(me, arg2);
1478 break;
1479 case PR_SET_FPEXC:
1480 error = SET_FPEXC_CTL(me, arg2);
1481 break;
1482 case PR_GET_FPEXC:
1483 error = GET_FPEXC_CTL(me, arg2);
1484 break;
1485 case PR_GET_TIMING:
1486 error = PR_TIMING_STATISTICAL;
1487 break;
1488 case PR_SET_TIMING:
1489 if (arg2 != PR_TIMING_STATISTICAL)
1490 error = -EINVAL;
1491 else
1492 error = 0;
1493 break;
1495 case PR_SET_NAME:
1496 comm[sizeof(me->comm)-1] = 0;
1497 if (strncpy_from_user(comm, (char __user *)arg2,
1498 sizeof(me->comm) - 1) < 0)
1499 return -EFAULT;
1500 set_task_comm(me, comm);
1501 return 0;
1502 case PR_GET_NAME:
1503 get_task_comm(comm, me);
1504 if (copy_to_user((char __user *)arg2, comm,
1505 sizeof(comm)))
1506 return -EFAULT;
1507 return 0;
1508 case PR_GET_ENDIAN:
1509 error = GET_ENDIAN(me, arg2);
1510 break;
1511 case PR_SET_ENDIAN:
1512 error = SET_ENDIAN(me, arg2);
1513 break;
1515 case PR_GET_SECCOMP:
1516 error = prctl_get_seccomp();
1517 break;
1518 case PR_SET_SECCOMP:
1519 error = prctl_set_seccomp(arg2);
1520 break;
1521 case PR_GET_TSC:
1522 error = GET_TSC_CTL(arg2);
1523 break;
1524 case PR_SET_TSC:
1525 error = SET_TSC_CTL(arg2);
1526 break;
1527 case PR_TASK_PERF_EVENTS_DISABLE:
1528 error = perf_event_task_disable();
1529 break;
1530 case PR_TASK_PERF_EVENTS_ENABLE:
1531 error = perf_event_task_enable();
1532 break;
1533 case PR_GET_TIMERSLACK:
1534 error = current->timer_slack_ns;
1535 break;
1536 case PR_SET_TIMERSLACK:
1537 if (arg2 <= 0)
1538 current->timer_slack_ns =
1539 current->default_timer_slack_ns;
1540 else
1541 current->timer_slack_ns = arg2;
1542 error = 0;
1543 break;
1544 case PR_MCE_KILL:
1545 if (arg4 | arg5)
1546 return -EINVAL;
1547 switch (arg2) {
1548 case PR_MCE_KILL_CLEAR:
1549 if (arg3 != 0)
1550 return -EINVAL;
1551 current->flags &= ~PF_MCE_PROCESS;
1552 break;
1553 case PR_MCE_KILL_SET:
1554 current->flags |= PF_MCE_PROCESS;
1555 if (arg3 == PR_MCE_KILL_EARLY)
1556 current->flags |= PF_MCE_EARLY;
1557 else if (arg3 == PR_MCE_KILL_LATE)
1558 current->flags &= ~PF_MCE_EARLY;
1559 else if (arg3 == PR_MCE_KILL_DEFAULT)
1560 current->flags &=
1561 ~(PF_MCE_EARLY|PF_MCE_PROCESS);
1562 else
1563 return -EINVAL;
1564 break;
1565 default:
1566 return -EINVAL;
1568 error = 0;
1569 break;
1570 case PR_MCE_KILL_GET:
1571 if (arg2 | arg3 | arg4 | arg5)
1572 return -EINVAL;
1573 if (current->flags & PF_MCE_PROCESS)
1574 error = (current->flags & PF_MCE_EARLY) ?
1575 PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE;
1576 else
1577 error = PR_MCE_KILL_DEFAULT;
1578 break;
1579 default:
1580 error = -EINVAL;
1581 break;
1583 return error;
1586 SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
1587 struct getcpu_cache __user *, unused)
1589 int err = 0;
1590 int cpu = raw_smp_processor_id();
1591 if (cpup)
1592 err |= put_user(cpu, cpup);
1593 if (nodep)
1594 err |= put_user(cpu_to_node(cpu), nodep);
1595 return err ? -EFAULT : 0;
1598 char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff";
1600 static void argv_cleanup(char **argv, char **envp)
1602 argv_free(argv);
1606 * orderly_poweroff - Trigger an orderly system poweroff
1607 * @force: force poweroff if command execution fails
1609 * This may be called from any context to trigger a system shutdown.
1610 * If the orderly shutdown fails, it will force an immediate shutdown.
1612 int orderly_poweroff(bool force)
1614 int argc;
1615 char **argv = argv_split(GFP_ATOMIC, poweroff_cmd, &argc);
1616 static char *envp[] = {
1617 "HOME=/",
1618 "PATH=/sbin:/bin:/usr/sbin:/usr/bin",
1619 NULL
1621 int ret = -ENOMEM;
1622 struct subprocess_info *info;
1624 if (argv == NULL) {
1625 printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n",
1626 __func__, poweroff_cmd);
1627 goto out;
1630 info = call_usermodehelper_setup(argv[0], argv, envp, GFP_ATOMIC);
1631 if (info == NULL) {
1632 argv_free(argv);
1633 goto out;
1636 call_usermodehelper_setcleanup(info, argv_cleanup);
1638 ret = call_usermodehelper_exec(info, UMH_NO_WAIT);
1640 out:
1641 if (ret && force) {
1642 printk(KERN_WARNING "Failed to start orderly shutdown: "
1643 "forcing the issue\n");
1645 /* I guess this should try to kick off some daemon to
1646 sync and poweroff asap. Or not even bother syncing
1647 if we're doing an emergency shutdown? */
1648 emergency_sync();
1649 kernel_power_off();
1652 return ret;
1654 EXPORT_SYMBOL_GPL(orderly_poweroff);