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[PATCH] ipmi: fix watchdog so the device can be reopened on an unexpected close
[linux/fpc-iii.git] / kernel / sys.c
blob7f43d6e62c7a05641e6b54fcbb9ffda74a8ffcbb
1 /*
2 * linux/kernel/sys.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7 #include <linux/config.h>
8 #include <linux/module.h>
9 #include <linux/mm.h>
10 #include <linux/utsname.h>
11 #include <linux/mman.h>
12 #include <linux/smp_lock.h>
13 #include <linux/notifier.h>
14 #include <linux/reboot.h>
15 #include <linux/prctl.h>
16 #include <linux/init.h>
17 #include <linux/highuid.h>
18 #include <linux/fs.h>
19 #include <linux/workqueue.h>
20 #include <linux/device.h>
21 #include <linux/key.h>
22 #include <linux/times.h>
23 #include <linux/posix-timers.h>
24 #include <linux/security.h>
25 #include <linux/dcookies.h>
26 #include <linux/suspend.h>
27 #include <linux/tty.h>
28
29 #include <linux/compat.h>
30 #include <linux/syscalls.h>
31
32 #include <asm/uaccess.h>
33 #include <asm/io.h>
34 #include <asm/unistd.h>
35
36 #ifndef SET_UNALIGN_CTL
37 # define SET_UNALIGN_CTL(a,b) (-EINVAL)
38 #endif
39 #ifndef GET_UNALIGN_CTL
40 # define GET_UNALIGN_CTL(a,b) (-EINVAL)
41 #endif
42 #ifndef SET_FPEMU_CTL
43 # define SET_FPEMU_CTL(a,b) (-EINVAL)
44 #endif
45 #ifndef GET_FPEMU_CTL
46 # define GET_FPEMU_CTL(a,b) (-EINVAL)
47 #endif
48 #ifndef SET_FPEXC_CTL
49 # define SET_FPEXC_CTL(a,b) (-EINVAL)
50 #endif
51 #ifndef GET_FPEXC_CTL
52 # define GET_FPEXC_CTL(a,b) (-EINVAL)
53 #endif
54
55 /*
56 * this is where the system-wide overflow UID and GID are defined, for
57 * architectures that now have 32-bit UID/GID but didn't in the past
58 */
59
60 int overflowuid = DEFAULT_OVERFLOWUID;
61 int overflowgid = DEFAULT_OVERFLOWGID;
62
63 #ifdef CONFIG_UID16
64 EXPORT_SYMBOL(overflowuid);
65 EXPORT_SYMBOL(overflowgid);
66 #endif
67
68 /*
69 * the same as above, but for filesystems which can only store a 16-bit
70 * UID and GID. as such, this is needed on all architectures
71 */
72
73 int fs_overflowuid = DEFAULT_FS_OVERFLOWUID;
74 int fs_overflowgid = DEFAULT_FS_OVERFLOWUID;
75
76 EXPORT_SYMBOL(fs_overflowuid);
77 EXPORT_SYMBOL(fs_overflowgid);
78
79 /*
80 * this indicates whether you can reboot with ctrl-alt-del: the default is yes
81 */
82
83 int C_A_D = 1;
84 int cad_pid = 1;
85
86 /*
87 * Notifier list for kernel code which wants to be called
88 * at shutdown. This is used to stop any idling DMA operations
89 * and the like.
90 */
91
92 static struct notifier_block *reboot_notifier_list;
93 static DEFINE_RWLOCK(notifier_lock);
94
95 /**
96 * notifier_chain_register - Add notifier to a notifier chain
97 * @list: Pointer to root list pointer
98 * @n: New entry in notifier chain
99 *
100 * Adds a notifier to a notifier chain.
101 *
102 * Currently always returns zero.
103 */
104
105 int notifier_chain_register(struct notifier_block **list, struct notifier_block *n)
106 {
107 write_lock(&notifier_lock);
108 while(*list)
109 {
110 if(n->priority > (*list)->priority)
111 break;
112 list= &((*list)->next);
113 }
114 n->next = *list;
115 *list=n;
116 write_unlock(&notifier_lock);
117 return 0;
118 }
119
120 EXPORT_SYMBOL(notifier_chain_register);
121
122 /**
123 * notifier_chain_unregister - Remove notifier from a notifier chain
124 * @nl: Pointer to root list pointer
125 * @n: New entry in notifier chain
126 *
127 * Removes a notifier from a notifier chain.
128 *
129 * Returns zero on success, or %-ENOENT on failure.
130 */
131
132 int notifier_chain_unregister(struct notifier_block **nl, struct notifier_block *n)
133 {
134 write_lock(&notifier_lock);
135 while((*nl)!=NULL)
136 {
137 if((*nl)==n)
138 {
139 *nl=n->next;
140 write_unlock(&notifier_lock);
141 return 0;
142 }
143 nl=&((*nl)->next);
144 }
145 write_unlock(&notifier_lock);
146 return -ENOENT;
147 }
148
149 EXPORT_SYMBOL(notifier_chain_unregister);
150
151 /**
152 * notifier_call_chain - Call functions in a notifier chain
153 * @n: Pointer to root pointer of notifier chain
154 * @val: Value passed unmodified to notifier function
155 * @v: Pointer passed unmodified to notifier function
156 *
157 * Calls each function in a notifier chain in turn.
158 *
159 * If the return value of the notifier can be and'd
160 * with %NOTIFY_STOP_MASK, then notifier_call_chain
161 * will return immediately, with the return value of
162 * the notifier function which halted execution.
163 * Otherwise, the return value is the return value
164 * of the last notifier function called.
165 */
166
167 int notifier_call_chain(struct notifier_block **n, unsigned long val, void *v)
168 {
169 int ret=NOTIFY_DONE;
170 struct notifier_block *nb = *n;
171
172 while(nb)
173 {
174 ret=nb->notifier_call(nb,val,v);
175 if(ret&NOTIFY_STOP_MASK)
176 {
177 return ret;
178 }
179 nb=nb->next;
180 }
181 return ret;
182 }
183
184 EXPORT_SYMBOL(notifier_call_chain);
185
186 /**
187 * register_reboot_notifier - Register function to be called at reboot time
188 * @nb: Info about notifier function to be called
189 *
190 * Registers a function with the list of functions
191 * to be called at reboot time.
192 *
193 * Currently always returns zero, as notifier_chain_register
194 * always returns zero.
195 */
196
197 int register_reboot_notifier(struct notifier_block * nb)
198 {
199 return notifier_chain_register(&reboot_notifier_list, nb);
200 }
201
202 EXPORT_SYMBOL(register_reboot_notifier);
203
204 /**
205 * unregister_reboot_notifier - Unregister previously registered reboot notifier
206 * @nb: Hook to be unregistered
207 *
208 * Unregisters a previously registered reboot
209 * notifier function.
210 *
211 * Returns zero on success, or %-ENOENT on failure.
212 */
213
214 int unregister_reboot_notifier(struct notifier_block * nb)
215 {
216 return notifier_chain_unregister(&reboot_notifier_list, nb);
217 }
218
219 EXPORT_SYMBOL(unregister_reboot_notifier);
220
221 static int set_one_prio(struct task_struct *p, int niceval, int error)
222 {
223 int no_nice;
224
225 if (p->uid != current->euid &&
226 p->euid != current->euid && !capable(CAP_SYS_NICE)) {
227 error = -EPERM;
228 goto out;
229 }
230 if (niceval < task_nice(p) && !can_nice(p, niceval)) {
231 error = -EACCES;
232 goto out;
233 }
234 no_nice = security_task_setnice(p, niceval);
235 if (no_nice) {
236 error = no_nice;
237 goto out;
238 }
239 if (error == -ESRCH)
240 error = 0;
241 set_user_nice(p, niceval);
242 out:
243 return error;
244 }
245
246 asmlinkage long sys_setpriority(int which, int who, int niceval)
247 {
248 struct task_struct *g, *p;
249 struct user_struct *user;
250 int error = -EINVAL;
251
252 if (which > 2 || which < 0)
253 goto out;
254
255 /* normalize: avoid signed division (rounding problems) */
256 error = -ESRCH;
257 if (niceval < -20)
258 niceval = -20;
259 if (niceval > 19)
260 niceval = 19;
261
262 read_lock(&tasklist_lock);
263 switch (which) {
264 case PRIO_PROCESS:
265 if (!who)
266 who = current->pid;
267 p = find_task_by_pid(who);
268 if (p)
269 error = set_one_prio(p, niceval, error);
270 break;
271 case PRIO_PGRP:
272 if (!who)
273 who = process_group(current);
274 do_each_task_pid(who, PIDTYPE_PGID, p) {
275 error = set_one_prio(p, niceval, error);
276 } while_each_task_pid(who, PIDTYPE_PGID, p);
277 break;
278 case PRIO_USER:
279 user = current->user;
280 if (!who)
281 who = current->uid;
282 else
283 if ((who != current->uid) && !(user = find_user(who)))
284 goto out_unlock; /* No processes for this user */
285
286 do_each_thread(g, p)
287 if (p->uid == who)
288 error = set_one_prio(p, niceval, error);
289 while_each_thread(g, p);
290 if (who != current->uid)
291 free_uid(user); /* For find_user() */
292 break;
293 }
294 out_unlock:
295 read_unlock(&tasklist_lock);
296 out:
297 return error;
298 }
299
300 /*
301 * Ugh. To avoid negative return values, "getpriority()" will
302 * not return the normal nice-value, but a negated value that
303 * has been offset by 20 (ie it returns 40..1 instead of -20..19)
304 * to stay compatible.
305 */
306 asmlinkage long sys_getpriority(int which, int who)
307 {
308 struct task_struct *g, *p;
309 struct user_struct *user;
310 long niceval, retval = -ESRCH;
311
312 if (which > 2 || which < 0)
313 return -EINVAL;
314
315 read_lock(&tasklist_lock);
316 switch (which) {
317 case PRIO_PROCESS:
318 if (!who)
319 who = current->pid;
320 p = find_task_by_pid(who);
321 if (p) {
322 niceval = 20 - task_nice(p);
323 if (niceval > retval)
324 retval = niceval;
325 }
326 break;
327 case PRIO_PGRP:
328 if (!who)
329 who = process_group(current);
330 do_each_task_pid(who, PIDTYPE_PGID, p) {
331 niceval = 20 - task_nice(p);
332 if (niceval > retval)
333 retval = niceval;
334 } while_each_task_pid(who, PIDTYPE_PGID, p);
335 break;
336 case PRIO_USER:
337 user = current->user;
338 if (!who)
339 who = current->uid;
340 else
341 if ((who != current->uid) && !(user = find_user(who)))
342 goto out_unlock; /* No processes for this user */
343
344 do_each_thread(g, p)
345 if (p->uid == who) {
346 niceval = 20 - task_nice(p);
347 if (niceval > retval)
348 retval = niceval;
349 }
350 while_each_thread(g, p);
351 if (who != current->uid)
352 free_uid(user); /* for find_user() */
353 break;
354 }
355 out_unlock:
356 read_unlock(&tasklist_lock);
357
358 return retval;
359 }
360
361
362 /*
363 * Reboot system call: for obvious reasons only root may call it,
364 * and even root needs to set up some magic numbers in the registers
365 * so that some mistake won't make this reboot the whole machine.
366 * You can also set the meaning of the ctrl-alt-del-key here.
367 *
368 * reboot doesn't sync: do that yourself before calling this.
369 */
370 asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user * arg)
371 {
372 char buffer[256];
373
374 /* We only trust the superuser with rebooting the system. */
375 if (!capable(CAP_SYS_BOOT))
376 return -EPERM;
377
378 /* For safety, we require "magic" arguments. */
379 if (magic1 != LINUX_REBOOT_MAGIC1 ||
380 (magic2 != LINUX_REBOOT_MAGIC2 &&
381 magic2 != LINUX_REBOOT_MAGIC2A &&
382 magic2 != LINUX_REBOOT_MAGIC2B &&
383 magic2 != LINUX_REBOOT_MAGIC2C))
384 return -EINVAL;
385
386 lock_kernel();
387 switch (cmd) {
388 case LINUX_REBOOT_CMD_RESTART:
389 notifier_call_chain(&reboot_notifier_list, SYS_RESTART, NULL);
390 system_state = SYSTEM_RESTART;
391 device_shutdown();
392 printk(KERN_EMERG "Restarting system.\n");
393 machine_restart(NULL);
394 break;
395
396 case LINUX_REBOOT_CMD_CAD_ON:
397 C_A_D = 1;
398 break;
399
400 case LINUX_REBOOT_CMD_CAD_OFF:
401 C_A_D = 0;
402 break;
403
404 case LINUX_REBOOT_CMD_HALT:
405 notifier_call_chain(&reboot_notifier_list, SYS_HALT, NULL);
406 system_state = SYSTEM_HALT;
407 device_shutdown();
408 printk(KERN_EMERG "System halted.\n");
409 machine_halt();
410 unlock_kernel();
411 do_exit(0);
412 break;
413
414 case LINUX_REBOOT_CMD_POWER_OFF:
415 notifier_call_chain(&reboot_notifier_list, SYS_POWER_OFF, NULL);
416 system_state = SYSTEM_POWER_OFF;
417 device_shutdown();
418 printk(KERN_EMERG "Power down.\n");
419 machine_power_off();
420 unlock_kernel();
421 do_exit(0);
422 break;
423
424 case LINUX_REBOOT_CMD_RESTART2:
425 if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) {
426 unlock_kernel();
427 return -EFAULT;
428 }
429 buffer[sizeof(buffer) - 1] = '\0';
430
431 notifier_call_chain(&reboot_notifier_list, SYS_RESTART, buffer);
432 system_state = SYSTEM_RESTART;
433 device_shutdown();
434 printk(KERN_EMERG "Restarting system with command '%s'.\n", buffer);
435 machine_restart(buffer);
436 break;
437
438 #ifdef CONFIG_SOFTWARE_SUSPEND
439 case LINUX_REBOOT_CMD_SW_SUSPEND:
440 {
441 int ret = software_suspend();
442 unlock_kernel();
443 return ret;
444 }
445 #endif
446
447 default:
448 unlock_kernel();
449 return -EINVAL;
450 }
451 unlock_kernel();
452 return 0;
453 }
454
455 static void deferred_cad(void *dummy)
456 {
457 notifier_call_chain(&reboot_notifier_list, SYS_RESTART, NULL);
458 machine_restart(NULL);
459 }
460
461 /*
462 * This function gets called by ctrl-alt-del - ie the keyboard interrupt.
463 * As it's called within an interrupt, it may NOT sync: the only choice
464 * is whether to reboot at once, or just ignore the ctrl-alt-del.
465 */
466 void ctrl_alt_del(void)
467 {
468 static DECLARE_WORK(cad_work, deferred_cad, NULL);
469
470 if (C_A_D)
471 schedule_work(&cad_work);
472 else
473 kill_proc(cad_pid, SIGINT, 1);
474 }
475
476
477 /*
478 * Unprivileged users may change the real gid to the effective gid
479 * or vice versa. (BSD-style)
480 *
481 * If you set the real gid at all, or set the effective gid to a value not
482 * equal to the real gid, then the saved gid is set to the new effective gid.
483 *
484 * This makes it possible for a setgid program to completely drop its
485 * privileges, which is often a useful assertion to make when you are doing
486 * a security audit over a program.
487 *
488 * The general idea is that a program which uses just setregid() will be
489 * 100% compatible with BSD. A program which uses just setgid() will be
490 * 100% compatible with POSIX with saved IDs.
491 *
492 * SMP: There are not races, the GIDs are checked only by filesystem
493 * operations (as far as semantic preservation is concerned).
494 */
495 asmlinkage long sys_setregid(gid_t rgid, gid_t egid)
496 {
497 int old_rgid = current->gid;
498 int old_egid = current->egid;
499 int new_rgid = old_rgid;
500 int new_egid = old_egid;
501 int retval;
502
503 retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE);
504 if (retval)
505 return retval;
506
507 if (rgid != (gid_t) -1) {
508 if ((old_rgid == rgid) ||
509 (current->egid==rgid) ||
510 capable(CAP_SETGID))
511 new_rgid = rgid;
512 else
513 return -EPERM;
514 }
515 if (egid != (gid_t) -1) {
516 if ((old_rgid == egid) ||
517 (current->egid == egid) ||
518 (current->sgid == egid) ||
519 capable(CAP_SETGID))
520 new_egid = egid;
521 else {
522 return -EPERM;
523 }
524 }
525 if (new_egid != old_egid)
526 {
527 current->mm->dumpable = 0;
528 smp_wmb();
529 }
530 if (rgid != (gid_t) -1 ||
531 (egid != (gid_t) -1 && egid != old_rgid))
532 current->sgid = new_egid;
533 current->fsgid = new_egid;
534 current->egid = new_egid;
535 current->gid = new_rgid;
536 key_fsgid_changed(current);
537 return 0;
538 }
539
540 /*
541 * setgid() is implemented like SysV w/ SAVED_IDS
542 *
543 * SMP: Same implicit races as above.
544 */
545 asmlinkage long sys_setgid(gid_t gid)
546 {
547 int old_egid = current->egid;
548 int retval;
549
550 retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID);
551 if (retval)
552 return retval;
553
554 if (capable(CAP_SETGID))
555 {
556 if(old_egid != gid)
557 {
558 current->mm->dumpable=0;
559 smp_wmb();
560 }
561 current->gid = current->egid = current->sgid = current->fsgid = gid;
562 }
563 else if ((gid == current->gid) || (gid == current->sgid))
564 {
565 if(old_egid != gid)
566 {
567 current->mm->dumpable=0;
568 smp_wmb();
569 }
570 current->egid = current->fsgid = gid;
571 }
572 else
573 return -EPERM;
574
575 key_fsgid_changed(current);
576 return 0;
577 }
578
579 static int set_user(uid_t new_ruid, int dumpclear)
580 {
581 struct user_struct *new_user;
582
583 new_user = alloc_uid(new_ruid);
584 if (!new_user)
585 return -EAGAIN;
586
587 if (atomic_read(&new_user->processes) >=
588 current->signal->rlim[RLIMIT_NPROC].rlim_cur &&
589 new_user != &root_user) {
590 free_uid(new_user);
591 return -EAGAIN;
592 }
593
594 switch_uid(new_user);
595
596 if(dumpclear)
597 {
598 current->mm->dumpable = 0;
599 smp_wmb();
600 }
601 current->uid = new_ruid;
602 return 0;
603 }
604
605 /*
606 * Unprivileged users may change the real uid to the effective uid
607 * or vice versa. (BSD-style)
608 *
609 * If you set the real uid at all, or set the effective uid to a value not
610 * equal to the real uid, then the saved uid is set to the new effective uid.
611 *
612 * This makes it possible for a setuid program to completely drop its
613 * privileges, which is often a useful assertion to make when you are doing
614 * a security audit over a program.
615 *
616 * The general idea is that a program which uses just setreuid() will be
617 * 100% compatible with BSD. A program which uses just setuid() will be
618 * 100% compatible with POSIX with saved IDs.
619 */
620 asmlinkage long sys_setreuid(uid_t ruid, uid_t euid)
621 {
622 int old_ruid, old_euid, old_suid, new_ruid, new_euid;
623 int retval;
624
625 retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE);
626 if (retval)
627 return retval;
628
629 new_ruid = old_ruid = current->uid;
630 new_euid = old_euid = current->euid;
631 old_suid = current->suid;
632
633 if (ruid != (uid_t) -1) {
634 new_ruid = ruid;
635 if ((old_ruid != ruid) &&
636 (current->euid != ruid) &&
637 !capable(CAP_SETUID))
638 return -EPERM;
639 }
640
641 if (euid != (uid_t) -1) {
642 new_euid = euid;
643 if ((old_ruid != euid) &&
644 (current->euid != euid) &&
645 (current->suid != euid) &&
646 !capable(CAP_SETUID))
647 return -EPERM;
648 }
649
650 if (new_ruid != old_ruid && set_user(new_ruid, new_euid != old_euid) < 0)
651 return -EAGAIN;
652
653 if (new_euid != old_euid)
654 {
655 current->mm->dumpable=0;
656 smp_wmb();
657 }
658 current->fsuid = current->euid = new_euid;
659 if (ruid != (uid_t) -1 ||
660 (euid != (uid_t) -1 && euid != old_ruid))
661 current->suid = current->euid;
662 current->fsuid = current->euid;
663
664 key_fsuid_changed(current);
665
666 return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RE);
667 }
668
669
670
671 /*
672 * setuid() is implemented like SysV with SAVED_IDS
673 *
674 * Note that SAVED_ID's is deficient in that a setuid root program
675 * like sendmail, for example, cannot set its uid to be a normal
676 * user and then switch back, because if you're root, setuid() sets
677 * the saved uid too. If you don't like this, blame the bright people
678 * in the POSIX committee and/or USG. Note that the BSD-style setreuid()
679 * will allow a root program to temporarily drop privileges and be able to
680 * regain them by swapping the real and effective uid.
681 */
682 asmlinkage long sys_setuid(uid_t uid)
683 {
684 int old_euid = current->euid;
685 int old_ruid, old_suid, new_ruid, new_suid;
686 int retval;
687
688 retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID);
689 if (retval)
690 return retval;
691
692 old_ruid = new_ruid = current->uid;
693 old_suid = current->suid;
694 new_suid = old_suid;
695
696 if (capable(CAP_SETUID)) {
697 if (uid != old_ruid && set_user(uid, old_euid != uid) < 0)
698 return -EAGAIN;
699 new_suid = uid;
700 } else if ((uid != current->uid) && (uid != new_suid))
701 return -EPERM;
702
703 if (old_euid != uid)
704 {
705 current->mm->dumpable = 0;
706 smp_wmb();
707 }
708 current->fsuid = current->euid = uid;
709 current->suid = new_suid;
710
711 key_fsuid_changed(current);
712
713 return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_ID);
714 }
715
716
717 /*
718 * This function implements a generic ability to update ruid, euid,
719 * and suid. This allows you to implement the 4.4 compatible seteuid().
720 */
721 asmlinkage long sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
722 {
723 int old_ruid = current->uid;
724 int old_euid = current->euid;
725 int old_suid = current->suid;
726 int retval;
727
728 retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES);
729 if (retval)
730 return retval;
731
732 if (!capable(CAP_SETUID)) {
733 if ((ruid != (uid_t) -1) && (ruid != current->uid) &&
734 (ruid != current->euid) && (ruid != current->suid))
735 return -EPERM;
736 if ((euid != (uid_t) -1) && (euid != current->uid) &&
737 (euid != current->euid) && (euid != current->suid))
738 return -EPERM;
739 if ((suid != (uid_t) -1) && (suid != current->uid) &&
740 (suid != current->euid) && (suid != current->suid))
741 return -EPERM;
742 }
743 if (ruid != (uid_t) -1) {
744 if (ruid != current->uid && set_user(ruid, euid != current->euid) < 0)
745 return -EAGAIN;
746 }
747 if (euid != (uid_t) -1) {
748 if (euid != current->euid)
749 {
750 current->mm->dumpable = 0;
751 smp_wmb();
752 }
753 current->euid = euid;
754 }
755 current->fsuid = current->euid;
756 if (suid != (uid_t) -1)
757 current->suid = suid;
758
759 key_fsuid_changed(current);
760
761 return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RES);
762 }
763
764 asmlinkage long sys_getresuid(uid_t __user *ruid, uid_t __user *euid, uid_t __user *suid)
765 {
766 int retval;
767
768 if (!(retval = put_user(current->uid, ruid)) &&
769 !(retval = put_user(current->euid, euid)))
770 retval = put_user(current->suid, suid);
771
772 return retval;
773 }
774
775 /*
776 * Same as above, but for rgid, egid, sgid.
777 */
778 asmlinkage long sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
779 {
780 int retval;
781
782 retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES);
783 if (retval)
784 return retval;
785
786 if (!capable(CAP_SETGID)) {
787 if ((rgid != (gid_t) -1) && (rgid != current->gid) &&
788 (rgid != current->egid) && (rgid != current->sgid))
789 return -EPERM;
790 if ((egid != (gid_t) -1) && (egid != current->gid) &&
791 (egid != current->egid) && (egid != current->sgid))
792 return -EPERM;
793 if ((sgid != (gid_t) -1) && (sgid != current->gid) &&
794 (sgid != current->egid) && (sgid != current->sgid))
795 return -EPERM;
796 }
797 if (egid != (gid_t) -1) {
798 if (egid != current->egid)
799 {
800 current->mm->dumpable = 0;
801 smp_wmb();
802 }
803 current->egid = egid;
804 }
805 current->fsgid = current->egid;
806 if (rgid != (gid_t) -1)
807 current->gid = rgid;
808 if (sgid != (gid_t) -1)
809 current->sgid = sgid;
810
811 key_fsgid_changed(current);
812 return 0;
813 }
814
815 asmlinkage long sys_getresgid(gid_t __user *rgid, gid_t __user *egid, gid_t __user *sgid)
816 {
817 int retval;
818
819 if (!(retval = put_user(current->gid, rgid)) &&
820 !(retval = put_user(current->egid, egid)))
821 retval = put_user(current->sgid, sgid);
822
823 return retval;
824 }
825
826
827 /*
828 * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This
829 * is used for "access()" and for the NFS daemon (letting nfsd stay at
830 * whatever uid it wants to). It normally shadows "euid", except when
831 * explicitly set by setfsuid() or for access..
832 */
833 asmlinkage long sys_setfsuid(uid_t uid)
834 {
835 int old_fsuid;
836
837 old_fsuid = current->fsuid;
838 if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS))
839 return old_fsuid;
840
841 if (uid == current->uid || uid == current->euid ||
842 uid == current->suid || uid == current->fsuid ||
843 capable(CAP_SETUID))
844 {
845 if (uid != old_fsuid)
846 {
847 current->mm->dumpable = 0;
848 smp_wmb();
849 }
850 current->fsuid = uid;
851 }
852
853 key_fsuid_changed(current);
854
855 security_task_post_setuid(old_fsuid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS);
856
857 return old_fsuid;
858 }
859
860 /*
861 * Samma på svenska..
862 */
863 asmlinkage long sys_setfsgid(gid_t gid)
864 {
865 int old_fsgid;
866
867 old_fsgid = current->fsgid;
868 if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS))
869 return old_fsgid;
870
871 if (gid == current->gid || gid == current->egid ||
872 gid == current->sgid || gid == current->fsgid ||
873 capable(CAP_SETGID))
874 {
875 if (gid != old_fsgid)
876 {
877 current->mm->dumpable = 0;
878 smp_wmb();
879 }
880 current->fsgid = gid;
881 key_fsgid_changed(current);
882 }
883 return old_fsgid;
884 }
885
886 asmlinkage long sys_times(struct tms __user * tbuf)
887 {
888 /*
889 * In the SMP world we might just be unlucky and have one of
890 * the times increment as we use it. Since the value is an
891 * atomically safe type this is just fine. Conceptually its
892 * as if the syscall took an instant longer to occur.
893 */
894 if (tbuf) {
895 struct tms tmp;
896 struct task_struct *tsk = current;
897 struct task_struct *t;
898 cputime_t utime, stime, cutime, cstime;
899
900 read_lock(&tasklist_lock);
901 utime = tsk->signal->utime;
902 stime = tsk->signal->stime;
903 t = tsk;
904 do {
905 utime = cputime_add(utime, t->utime);
906 stime = cputime_add(stime, t->stime);
907 t = next_thread(t);
908 } while (t != tsk);
909
910 /*
911 * While we have tasklist_lock read-locked, no dying thread
912 * can be updating current->signal->[us]time. Instead,
913 * we got their counts included in the live thread loop.
914 * However, another thread can come in right now and
915 * do a wait call that updates current->signal->c[us]time.
916 * To make sure we always see that pair updated atomically,
917 * we take the siglock around fetching them.
918 */
919 spin_lock_irq(&tsk->sighand->siglock);
920 cutime = tsk->signal->cutime;
921 cstime = tsk->signal->cstime;
922 spin_unlock_irq(&tsk->sighand->siglock);
923 read_unlock(&tasklist_lock);
924
925 tmp.tms_utime = cputime_to_clock_t(utime);
926 tmp.tms_stime = cputime_to_clock_t(stime);
927 tmp.tms_cutime = cputime_to_clock_t(cutime);
928 tmp.tms_cstime = cputime_to_clock_t(cstime);
929 if (copy_to_user(tbuf, &tmp, sizeof(struct tms)))
930 return -EFAULT;
931 }
932 return (long) jiffies_64_to_clock_t(get_jiffies_64());
933 }
934
935 /*
936 * This needs some heavy checking ...
937 * I just haven't the stomach for it. I also don't fully
938 * understand sessions/pgrp etc. Let somebody who does explain it.
939 *
940 * OK, I think I have the protection semantics right.... this is really
941 * only important on a multi-user system anyway, to make sure one user
942 * can't send a signal to a process owned by another. -TYT, 12/12/91
943 *
944 * Auch. Had to add the 'did_exec' flag to conform completely to POSIX.
945 * LBT 04.03.94
946 */
947
948 asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
949 {
950 struct task_struct *p;
951 int err = -EINVAL;
952
953 if (!pid)
954 pid = current->pid;
955 if (!pgid)
956 pgid = pid;
957 if (pgid < 0)
958 return -EINVAL;
959
960 /* From this point forward we keep holding onto the tasklist lock
961 * so that our parent does not change from under us. -DaveM
962 */
963 write_lock_irq(&tasklist_lock);
964
965 err = -ESRCH;
966 p = find_task_by_pid(pid);
967 if (!p)
968 goto out;
969
970 err = -EINVAL;
971 if (!thread_group_leader(p))
972 goto out;
973
974 if (p->parent == current || p->real_parent == current) {
975 err = -EPERM;
976 if (p->signal->session != current->signal->session)
977 goto out;
978 err = -EACCES;
979 if (p->did_exec)
980 goto out;
981 } else {
982 err = -ESRCH;
983 if (p != current)
984 goto out;
985 }
986
987 err = -EPERM;
988 if (p->signal->leader)
989 goto out;
990
991 if (pgid != pid) {
992 struct task_struct *p;
993
994 do_each_task_pid(pgid, PIDTYPE_PGID, p) {
995 if (p->signal->session == current->signal->session)
996 goto ok_pgid;
997 } while_each_task_pid(pgid, PIDTYPE_PGID, p);
998 goto out;
999 }
1000
1001 ok_pgid:
1002 err = security_task_setpgid(p, pgid);
1003 if (err)
1004 goto out;
1005
1006 if (process_group(p) != pgid) {
1007 detach_pid(p, PIDTYPE_PGID);
1008 p->signal->pgrp = pgid;
1009 attach_pid(p, PIDTYPE_PGID, pgid);
1010 }
1011
1012 err = 0;
1013 out:
1014 /* All paths lead to here, thus we are safe. -DaveM */
1015 write_unlock_irq(&tasklist_lock);
1016 return err;
1017 }
1018
1019 asmlinkage long sys_getpgid(pid_t pid)
1020 {
1021 if (!pid) {
1022 return process_group(current);
1023 } else {
1024 int retval;
1025 struct task_struct *p;
1026
1027 read_lock(&tasklist_lock);
1028 p = find_task_by_pid(pid);
1029
1030 retval = -ESRCH;
1031 if (p) {
1032 retval = security_task_getpgid(p);
1033 if (!retval)
1034 retval = process_group(p);
1035 }
1036 read_unlock(&tasklist_lock);
1037 return retval;
1038 }
1039 }
1040
1041 #ifdef __ARCH_WANT_SYS_GETPGRP
1042
1043 asmlinkage long sys_getpgrp(void)
1044 {
1045 /* SMP - assuming writes are word atomic this is fine */
1046 return process_group(current);
1047 }
1048
1049 #endif
1050
1051 asmlinkage long sys_getsid(pid_t pid)
1052 {
1053 if (!pid) {
1054 return current->signal->session;
1055 } else {
1056 int retval;
1057 struct task_struct *p;
1058
1059 read_lock(&tasklist_lock);
1060 p = find_task_by_pid(pid);
1061
1062 retval = -ESRCH;
1063 if(p) {
1064 retval = security_task_getsid(p);
1065 if (!retval)
1066 retval = p->signal->session;
1067 }
1068 read_unlock(&tasklist_lock);
1069 return retval;
1070 }
1071 }
1072
1073 asmlinkage long sys_setsid(void)
1074 {
1075 struct pid *pid;
1076 int err = -EPERM;
1077
1078 if (!thread_group_leader(current))
1079 return -EINVAL;
1080
1081 down(&tty_sem);
1082 write_lock_irq(&tasklist_lock);
1083
1084 pid = find_pid(PIDTYPE_PGID, current->pid);
1085 if (pid)
1086 goto out;
1087
1088 current->signal->leader = 1;
1089 __set_special_pids(current->pid, current->pid);
1090 current->signal->tty = NULL;
1091 current->signal->tty_old_pgrp = 0;
1092 err = process_group(current);
1093 out:
1094 write_unlock_irq(&tasklist_lock);
1095 up(&tty_sem);
1096 return err;
1097 }
1098
1099 /*
1100 * Supplementary group IDs
1101 */
1102
1103 /* init to 2 - one for init_task, one to ensure it is never freed */
1104 struct group_info init_groups = { .usage = ATOMIC_INIT(2) };
1105
1106 struct group_info *groups_alloc(int gidsetsize)
1107 {
1108 struct group_info *group_info;
1109 int nblocks;
1110 int i;
1111
1112 nblocks = (gidsetsize + NGROUPS_PER_BLOCK - 1) / NGROUPS_PER_BLOCK;
1113 /* Make sure we always allocate at least one indirect block pointer */
1114 nblocks = nblocks ? : 1;
1115 group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *), GFP_USER);
1116 if (!group_info)
1117 return NULL;
1118 group_info->ngroups = gidsetsize;
1119 group_info->nblocks = nblocks;
1120 atomic_set(&group_info->usage, 1);
1121
1122 if (gidsetsize <= NGROUPS_SMALL) {
1123 group_info->blocks[0] = group_info->small_block;
1124 } else {
1125 for (i = 0; i < nblocks; i++) {
1126 gid_t *b;
1127 b = (void *)__get_free_page(GFP_USER);
1128 if (!b)
1129 goto out_undo_partial_alloc;
1130 group_info->blocks[i] = b;
1131 }
1132 }
1133 return group_info;
1134
1135 out_undo_partial_alloc:
1136 while (--i >= 0) {
1137 free_page((unsigned long)group_info->blocks[i]);
1138 }
1139 kfree(group_info);
1140 return NULL;
1141 }
1142
1143 EXPORT_SYMBOL(groups_alloc);
1144
1145 void groups_free(struct group_info *group_info)
1146 {
1147 if (group_info->blocks[0] != group_info->small_block) {
1148 int i;
1149 for (i = 0; i < group_info->nblocks; i++)
1150 free_page((unsigned long)group_info->blocks[i]);
1151 }
1152 kfree(group_info);
1153 }
1154
1155 EXPORT_SYMBOL(groups_free);
1156
1157 /* export the group_info to a user-space array */
1158 static int groups_to_user(gid_t __user *grouplist,
1159 struct group_info *group_info)
1160 {
1161 int i;
1162 int count = group_info->ngroups;
1163
1164 for (i = 0; i < group_info->nblocks; i++) {
1165 int cp_count = min(NGROUPS_PER_BLOCK, count);
1166 int off = i * NGROUPS_PER_BLOCK;
1167 int len = cp_count * sizeof(*grouplist);
1168
1169 if (copy_to_user(grouplist+off, group_info->blocks[i], len))
1170 return -EFAULT;
1171
1172 count -= cp_count;
1173 }
1174 return 0;
1175 }
1176
1177 /* fill a group_info from a user-space array - it must be allocated already */
1178 static int groups_from_user(struct group_info *group_info,
1179 gid_t __user *grouplist)
1180 {
1181 int i;
1182 int count = group_info->ngroups;
1183
1184 for (i = 0; i < group_info->nblocks; i++) {
1185 int cp_count = min(NGROUPS_PER_BLOCK, count);
1186 int off = i * NGROUPS_PER_BLOCK;
1187 int len = cp_count * sizeof(*grouplist);
1188
1189 if (copy_from_user(group_info->blocks[i], grouplist+off, len))
1190 return -EFAULT;
1191
1192 count -= cp_count;
1193 }
1194 return 0;
1195 }
1196
1197 /* a simple shell-metzner sort */
1198 static void groups_sort(struct group_info *group_info)
1199 {
1200 int base, max, stride;
1201 int gidsetsize = group_info->ngroups;
1202
1203 for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1)
1204 ; /* nothing */
1205 stride /= 3;
1206
1207 while (stride) {
1208 max = gidsetsize - stride;
1209 for (base = 0; base < max; base++) {
1210 int left = base;
1211 int right = left + stride;
1212 gid_t tmp = GROUP_AT(group_info, right);
1213
1214 while (left >= 0 && GROUP_AT(group_info, left) > tmp) {
1215 GROUP_AT(group_info, right) =
1216 GROUP_AT(group_info, left);
1217 right = left;
1218 left -= stride;
1219 }
1220 GROUP_AT(group_info, right) = tmp;
1221 }
1222 stride /= 3;
1223 }
1224 }
1225
1226 /* a simple bsearch */
1227 static int groups_search(struct group_info *group_info, gid_t grp)
1228 {
1229 int left, right;
1230
1231 if (!group_info)
1232 return 0;
1233
1234 left = 0;
1235 right = group_info->ngroups;
1236 while (left < right) {
1237 int mid = (left+right)/2;
1238 int cmp = grp - GROUP_AT(group_info, mid);
1239 if (cmp > 0)
1240 left = mid + 1;
1241 else if (cmp < 0)
1242 right = mid;
1243 else
1244 return 1;
1245 }
1246 return 0;
1247 }
1248
1249 /* validate and set current->group_info */
1250 int set_current_groups(struct group_info *group_info)
1251 {
1252 int retval;
1253 struct group_info *old_info;
1254
1255 retval = security_task_setgroups(group_info);
1256 if (retval)
1257 return retval;
1258
1259 groups_sort(group_info);
1260 get_group_info(group_info);
1261
1262 task_lock(current);
1263 old_info = current->group_info;
1264 current->group_info = group_info;
1265 task_unlock(current);
1266
1267 put_group_info(old_info);
1268
1269 return 0;
1270 }
1271
1272 EXPORT_SYMBOL(set_current_groups);
1273
1274 asmlinkage long sys_getgroups(int gidsetsize, gid_t __user *grouplist)
1275 {
1276 int i = 0;
1277
1278 /*
1279 * SMP: Nobody else can change our grouplist. Thus we are
1280 * safe.
1281 */
1282
1283 if (gidsetsize < 0)
1284 return -EINVAL;
1285
1286 /* no need to grab task_lock here; it cannot change */
1287 get_group_info(current->group_info);
1288 i = current->group_info->ngroups;
1289 if (gidsetsize) {
1290 if (i > gidsetsize) {
1291 i = -EINVAL;
1292 goto out;
1293 }
1294 if (groups_to_user(grouplist, current->group_info)) {
1295 i = -EFAULT;
1296 goto out;
1297 }
1298 }
1299 out:
1300 put_group_info(current->group_info);
1301 return i;
1302 }
1303
1304 /*
1305 * SMP: Our groups are copy-on-write. We can set them safely
1306 * without another task interfering.
1307 */
1308
1309 asmlinkage long sys_setgroups(int gidsetsize, gid_t __user *grouplist)
1310 {
1311 struct group_info *group_info;
1312 int retval;
1313
1314 if (!capable(CAP_SETGID))
1315 return -EPERM;
1316 if ((unsigned)gidsetsize > NGROUPS_MAX)
1317 return -EINVAL;
1318
1319 group_info = groups_alloc(gidsetsize);
1320 if (!group_info)
1321 return -ENOMEM;
1322 retval = groups_from_user(group_info, grouplist);
1323 if (retval) {
1324 put_group_info(group_info);
1325 return retval;
1326 }
1327
1328 retval = set_current_groups(group_info);
1329 put_group_info(group_info);
1330
1331 return retval;
1332 }
1333
1334 /*
1335 * Check whether we're fsgid/egid or in the supplemental group..
1336 */
1337 int in_group_p(gid_t grp)
1338 {
1339 int retval = 1;
1340 if (grp != current->fsgid) {
1341 get_group_info(current->group_info);
1342 retval = groups_search(current->group_info, grp);
1343 put_group_info(current->group_info);
1344 }
1345 return retval;
1346 }
1347
1348 EXPORT_SYMBOL(in_group_p);
1349
1350 int in_egroup_p(gid_t grp)
1351 {
1352 int retval = 1;
1353 if (grp != current->egid) {
1354 get_group_info(current->group_info);
1355 retval = groups_search(current->group_info, grp);
1356 put_group_info(current->group_info);
1357 }
1358 return retval;
1359 }
1360
1361 EXPORT_SYMBOL(in_egroup_p);
1362
1363 DECLARE_RWSEM(uts_sem);
1364
1365 EXPORT_SYMBOL(uts_sem);
1366
1367 asmlinkage long sys_newuname(struct new_utsname __user * name)
1368 {
1369 int errno = 0;
1370
1371 down_read(&uts_sem);
1372 if (copy_to_user(name,&system_utsname,sizeof *name))
1373 errno = -EFAULT;
1374 up_read(&uts_sem);
1375 return errno;
1376 }
1377
1378 asmlinkage long sys_sethostname(char __user *name, int len)
1379 {
1380 int errno;
1381 char tmp[__NEW_UTS_LEN];
1382
1383 if (!capable(CAP_SYS_ADMIN))
1384 return -EPERM;
1385 if (len < 0 || len > __NEW_UTS_LEN)
1386 return -EINVAL;
1387 down_write(&uts_sem);
1388 errno = -EFAULT;
1389 if (!copy_from_user(tmp, name, len)) {
1390 memcpy(system_utsname.nodename, tmp, len);
1391 system_utsname.nodename[len] = 0;
1392 errno = 0;
1393 }
1394 up_write(&uts_sem);
1395 return errno;
1396 }
1397
1398 #ifdef __ARCH_WANT_SYS_GETHOSTNAME
1399
1400 asmlinkage long sys_gethostname(char __user *name, int len)
1401 {
1402 int i, errno;
1403
1404 if (len < 0)
1405 return -EINVAL;
1406 down_read(&uts_sem);
1407 i = 1 + strlen(system_utsname.nodename);
1408 if (i > len)
1409 i = len;
1410 errno = 0;
1411 if (copy_to_user(name, system_utsname.nodename, i))
1412 errno = -EFAULT;
1413 up_read(&uts_sem);
1414 return errno;
1415 }
1416
1417 #endif
1418
1419 /*
1420 * Only setdomainname; getdomainname can be implemented by calling
1421 * uname()
1422 */
1423 asmlinkage long sys_setdomainname(char __user *name, int len)
1424 {
1425 int errno;
1426 char tmp[__NEW_UTS_LEN];
1427
1428 if (!capable(CAP_SYS_ADMIN))
1429 return -EPERM;
1430 if (len < 0 || len > __NEW_UTS_LEN)
1431 return -EINVAL;
1432
1433 down_write(&uts_sem);
1434 errno = -EFAULT;
1435 if (!copy_from_user(tmp, name, len)) {
1436 memcpy(system_utsname.domainname, tmp, len);
1437 system_utsname.domainname[len] = 0;
1438 errno = 0;
1439 }
1440 up_write(&uts_sem);
1441 return errno;
1442 }
1443
1444 asmlinkage long sys_getrlimit(unsigned int resource, struct rlimit __user *rlim)
1445 {
1446 if (resource >= RLIM_NLIMITS)
1447 return -EINVAL;
1448 else {
1449 struct rlimit value;
1450 task_lock(current->group_leader);
1451 value = current->signal->rlim[resource];
1452 task_unlock(current->group_leader);
1453 return copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0;
1454 }
1455 }
1456
1457 #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
1458
1459 /*
1460 * Back compatibility for getrlimit. Needed for some apps.
1461 */
1462
1463 asmlinkage long sys_old_getrlimit(unsigned int resource, struct rlimit __user *rlim)
1464 {
1465 struct rlimit x;
1466 if (resource >= RLIM_NLIMITS)
1467 return -EINVAL;
1468
1469 task_lock(current->group_leader);
1470 x = current->signal->rlim[resource];
1471 task_unlock(current->group_leader);
1472 if(x.rlim_cur > 0x7FFFFFFF)
1473 x.rlim_cur = 0x7FFFFFFF;
1474 if(x.rlim_max > 0x7FFFFFFF)
1475 x.rlim_max = 0x7FFFFFFF;
1476 return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0;
1477 }
1478
1479 #endif
1480
1481 asmlinkage long sys_setrlimit(unsigned int resource, struct rlimit __user *rlim)
1482 {
1483 struct rlimit new_rlim, *old_rlim;
1484 int retval;
1485
1486 if (resource >= RLIM_NLIMITS)
1487 return -EINVAL;
1488 if(copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
1489 return -EFAULT;
1490 if (new_rlim.rlim_cur > new_rlim.rlim_max)
1491 return -EINVAL;
1492 old_rlim = current->signal->rlim + resource;
1493 if ((new_rlim.rlim_max > old_rlim->rlim_max) &&
1494 !capable(CAP_SYS_RESOURCE))
1495 return -EPERM;
1496 if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > NR_OPEN)
1497 return -EPERM;
1498
1499 retval = security_task_setrlimit(resource, &new_rlim);
1500 if (retval)
1501 return retval;
1502
1503 task_lock(current->group_leader);
1504 *old_rlim = new_rlim;
1505 task_unlock(current->group_leader);
1506
1507 if (resource == RLIMIT_CPU && new_rlim.rlim_cur != RLIM_INFINITY &&
1508 (cputime_eq(current->signal->it_prof_expires, cputime_zero) ||
1509 new_rlim.rlim_cur <= cputime_to_secs(
1510 current->signal->it_prof_expires))) {
1511 cputime_t cputime = secs_to_cputime(new_rlim.rlim_cur);
1512 read_lock(&tasklist_lock);
1513 spin_lock_irq(&current->sighand->siglock);
1514 set_process_cpu_timer(current, CPUCLOCK_PROF,
1515 &cputime, NULL);
1516 spin_unlock_irq(&current->sighand->siglock);
1517 read_unlock(&tasklist_lock);
1518 }
1519
1520 return 0;
1521 }
1522
1523 /*
1524 * It would make sense to put struct rusage in the task_struct,
1525 * except that would make the task_struct be *really big*. After
1526 * task_struct gets moved into malloc'ed memory, it would
1527 * make sense to do this. It will make moving the rest of the information
1528 * a lot simpler! (Which we're not doing right now because we're not
1529 * measuring them yet).
1530 *
1531 * This expects to be called with tasklist_lock read-locked or better,
1532 * and the siglock not locked. It may momentarily take the siglock.
1533 *
1534 * When sampling multiple threads for RUSAGE_SELF, under SMP we might have
1535 * races with threads incrementing their own counters. But since word
1536 * reads are atomic, we either get new values or old values and we don't
1537 * care which for the sums. We always take the siglock to protect reading
1538 * the c* fields from p->signal from races with exit.c updating those
1539 * fields when reaping, so a sample either gets all the additions of a
1540 * given child after it's reaped, or none so this sample is before reaping.
1541 */
1542
1543 static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
1544 {
1545 struct task_struct *t;
1546 unsigned long flags;
1547 cputime_t utime, stime;
1548
1549 memset((char *) r, 0, sizeof *r);
1550
1551 if (unlikely(!p->signal))
1552 return;
1553
1554 switch (who) {
1555 case RUSAGE_CHILDREN:
1556 spin_lock_irqsave(&p->sighand->siglock, flags);
1557 utime = p->signal->cutime;
1558 stime = p->signal->cstime;
1559 r->ru_nvcsw = p->signal->cnvcsw;
1560 r->ru_nivcsw = p->signal->cnivcsw;
1561 r->ru_minflt = p->signal->cmin_flt;
1562 r->ru_majflt = p->signal->cmaj_flt;
1563 spin_unlock_irqrestore(&p->sighand->siglock, flags);
1564 cputime_to_timeval(utime, &r->ru_utime);
1565 cputime_to_timeval(stime, &r->ru_stime);
1566 break;
1567 case RUSAGE_SELF:
1568 spin_lock_irqsave(&p->sighand->siglock, flags);
1569 utime = stime = cputime_zero;
1570 goto sum_group;
1571 case RUSAGE_BOTH:
1572 spin_lock_irqsave(&p->sighand->siglock, flags);
1573 utime = p->signal->cutime;
1574 stime = p->signal->cstime;
1575 r->ru_nvcsw = p->signal->cnvcsw;
1576 r->ru_nivcsw = p->signal->cnivcsw;
1577 r->ru_minflt = p->signal->cmin_flt;
1578 r->ru_majflt = p->signal->cmaj_flt;
1579 sum_group:
1580 utime = cputime_add(utime, p->signal->utime);
1581 stime = cputime_add(stime, p->signal->stime);
1582 r->ru_nvcsw += p->signal->nvcsw;
1583 r->ru_nivcsw += p->signal->nivcsw;
1584 r->ru_minflt += p->signal->min_flt;
1585 r->ru_majflt += p->signal->maj_flt;
1586 t = p;
1587 do {
1588 utime = cputime_add(utime, t->utime);
1589 stime = cputime_add(stime, t->stime);
1590 r->ru_nvcsw += t->nvcsw;
1591 r->ru_nivcsw += t->nivcsw;
1592 r->ru_minflt += t->min_flt;
1593 r->ru_majflt += t->maj_flt;
1594 t = next_thread(t);
1595 } while (t != p);
1596 spin_unlock_irqrestore(&p->sighand->siglock, flags);
1597 cputime_to_timeval(utime, &r->ru_utime);
1598 cputime_to_timeval(stime, &r->ru_stime);
1599 break;
1600 default:
1601 BUG();
1602 }
1603 }
1604
1605 int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
1606 {
1607 struct rusage r;
1608 read_lock(&tasklist_lock);
1609 k_getrusage(p, who, &r);
1610 read_unlock(&tasklist_lock);
1611 return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
1612 }
1613
1614 asmlinkage long sys_getrusage(int who, struct rusage __user *ru)
1615 {
1616 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN)
1617 return -EINVAL;
1618 return getrusage(current, who, ru);
1619 }
1620
1621 asmlinkage long sys_umask(int mask)
1622 {
1623 mask = xchg(&current->fs->umask, mask & S_IRWXUGO);
1624 return mask;
1625 }
1626
1627 asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
1628 unsigned long arg4, unsigned long arg5)
1629 {
1630 long error;
1631 int sig;
1632
1633 error = security_task_prctl(option, arg2, arg3, arg4, arg5);
1634 if (error)
1635 return error;
1636
1637 switch (option) {
1638 case PR_SET_PDEATHSIG:
1639 sig = arg2;
1640 if (sig < 0 || sig > _NSIG) {
1641 error = -EINVAL;
1642 break;
1643 }
1644 current->pdeath_signal = sig;
1645 break;
1646 case PR_GET_PDEATHSIG:
1647 error = put_user(current->pdeath_signal, (int __user *)arg2);
1648 break;
1649 case PR_GET_DUMPABLE:
1650 if (current->mm->dumpable)
1651 error = 1;
1652 break;
1653 case PR_SET_DUMPABLE:
1654 if (arg2 != 0 && arg2 != 1) {
1655 error = -EINVAL;
1656 break;
1657 }
1658 current->mm->dumpable = arg2;
1659 break;
1660
1661 case PR_SET_UNALIGN:
1662 error = SET_UNALIGN_CTL(current, arg2);
1663 break;
1664 case PR_GET_UNALIGN:
1665 error = GET_UNALIGN_CTL(current, arg2);
1666 break;
1667 case PR_SET_FPEMU:
1668 error = SET_FPEMU_CTL(current, arg2);
1669 break;
1670 case PR_GET_FPEMU:
1671 error = GET_FPEMU_CTL(current, arg2);
1672 break;
1673 case PR_SET_FPEXC:
1674 error = SET_FPEXC_CTL(current, arg2);
1675 break;
1676 case PR_GET_FPEXC:
1677 error = GET_FPEXC_CTL(current, arg2);
1678 break;
1679 case PR_GET_TIMING:
1680 error = PR_TIMING_STATISTICAL;
1681 break;
1682 case PR_SET_TIMING:
1683 if (arg2 == PR_TIMING_STATISTICAL)
1684 error = 0;
1685 else
1686 error = -EINVAL;
1687 break;
1688
1689 case PR_GET_KEEPCAPS:
1690 if (current->keep_capabilities)
1691 error = 1;
1692 break;
1693 case PR_SET_KEEPCAPS:
1694 if (arg2 != 0 && arg2 != 1) {
1695 error = -EINVAL;
1696 break;
1697 }
1698 current->keep_capabilities = arg2;
1699 break;
1700 case PR_SET_NAME: {
1701 struct task_struct *me = current;
1702 unsigned char ncomm[sizeof(me->comm)];
1703
1704 ncomm[sizeof(me->comm)-1] = 0;
1705 if (strncpy_from_user(ncomm, (char __user *)arg2,
1706 sizeof(me->comm)-1) < 0)
1707 return -EFAULT;
1708 set_task_comm(me, ncomm);
1709 return 0;
1710 }
1711 case PR_GET_NAME: {
1712 struct task_struct *me = current;
1713 unsigned char tcomm[sizeof(me->comm)];
1714
1715 get_task_comm(tcomm, me);
1716 if (copy_to_user((char __user *)arg2, tcomm, sizeof(tcomm)))
1717 return -EFAULT;
1718 return 0;
1719 }
1720 default:
1721 error = -EINVAL;
1722 break;
1723 }
1724 return error;
1725 }
Linux with added FPC-III support