Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/kernel/sys.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | */ | |
6 | ||
1da177e4 LT |
7 | #include <linux/module.h> |
8 | #include <linux/mm.h> | |
9 | #include <linux/utsname.h> | |
10 | #include <linux/mman.h> | |
11 | #include <linux/smp_lock.h> | |
12 | #include <linux/notifier.h> | |
13 | #include <linux/reboot.h> | |
14 | #include <linux/prctl.h> | |
1da177e4 LT |
15 | #include <linux/highuid.h> |
16 | #include <linux/fs.h> | |
3e88c553 | 17 | #include <linux/resource.h> |
dc009d92 EB |
18 | #include <linux/kernel.h> |
19 | #include <linux/kexec.h> | |
1da177e4 | 20 | #include <linux/workqueue.h> |
c59ede7b | 21 | #include <linux/capability.h> |
1da177e4 LT |
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> | |
7ed20e1a | 30 | #include <linux/signal.h> |
9f46080c | 31 | #include <linux/cn_proc.h> |
3cfc348b | 32 | #include <linux/getcpu.h> |
6eaeeaba | 33 | #include <linux/task_io_accounting_ops.h> |
1d9d02fe | 34 | #include <linux/seccomp.h> |
4047727e | 35 | #include <linux/cpu.h> |
1da177e4 LT |
36 | |
37 | #include <linux/compat.h> | |
38 | #include <linux/syscalls.h> | |
00d7c05a | 39 | #include <linux/kprobes.h> |
acce292c | 40 | #include <linux/user_namespace.h> |
1da177e4 LT |
41 | |
42 | #include <asm/uaccess.h> | |
43 | #include <asm/io.h> | |
44 | #include <asm/unistd.h> | |
45 | ||
46 | #ifndef SET_UNALIGN_CTL | |
47 | # define SET_UNALIGN_CTL(a,b) (-EINVAL) | |
48 | #endif | |
49 | #ifndef GET_UNALIGN_CTL | |
50 | # define GET_UNALIGN_CTL(a,b) (-EINVAL) | |
51 | #endif | |
52 | #ifndef SET_FPEMU_CTL | |
53 | # define SET_FPEMU_CTL(a,b) (-EINVAL) | |
54 | #endif | |
55 | #ifndef GET_FPEMU_CTL | |
56 | # define GET_FPEMU_CTL(a,b) (-EINVAL) | |
57 | #endif | |
58 | #ifndef SET_FPEXC_CTL | |
59 | # define SET_FPEXC_CTL(a,b) (-EINVAL) | |
60 | #endif | |
61 | #ifndef GET_FPEXC_CTL | |
62 | # define GET_FPEXC_CTL(a,b) (-EINVAL) | |
63 | #endif | |
651d765d AB |
64 | #ifndef GET_ENDIAN |
65 | # define GET_ENDIAN(a,b) (-EINVAL) | |
66 | #endif | |
67 | #ifndef SET_ENDIAN | |
68 | # define SET_ENDIAN(a,b) (-EINVAL) | |
69 | #endif | |
1da177e4 LT |
70 | |
71 | /* | |
72 | * this is where the system-wide overflow UID and GID are defined, for | |
73 | * architectures that now have 32-bit UID/GID but didn't in the past | |
74 | */ | |
75 | ||
76 | int overflowuid = DEFAULT_OVERFLOWUID; | |
77 | int overflowgid = DEFAULT_OVERFLOWGID; | |
78 | ||
79 | #ifdef CONFIG_UID16 | |
80 | EXPORT_SYMBOL(overflowuid); | |
81 | EXPORT_SYMBOL(overflowgid); | |
82 | #endif | |
83 | ||
84 | /* | |
85 | * the same as above, but for filesystems which can only store a 16-bit | |
86 | * UID and GID. as such, this is needed on all architectures | |
87 | */ | |
88 | ||
89 | int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; | |
90 | int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; | |
91 | ||
92 | EXPORT_SYMBOL(fs_overflowuid); | |
93 | EXPORT_SYMBOL(fs_overflowgid); | |
94 | ||
95 | /* | |
96 | * this indicates whether you can reboot with ctrl-alt-del: the default is yes | |
97 | */ | |
98 | ||
99 | int C_A_D = 1; | |
9ec52099 CLG |
100 | struct pid *cad_pid; |
101 | EXPORT_SYMBOL(cad_pid); | |
1da177e4 | 102 | |
bd804eba RW |
103 | /* |
104 | * If set, this is used for preparing the system to power off. | |
105 | */ | |
106 | ||
107 | void (*pm_power_off_prepare)(void); | |
bd804eba | 108 | |
1da177e4 LT |
109 | static int set_one_prio(struct task_struct *p, int niceval, int error) |
110 | { | |
111 | int no_nice; | |
112 | ||
113 | if (p->uid != current->euid && | |
114 | p->euid != current->euid && !capable(CAP_SYS_NICE)) { | |
115 | error = -EPERM; | |
116 | goto out; | |
117 | } | |
e43379f1 | 118 | if (niceval < task_nice(p) && !can_nice(p, niceval)) { |
1da177e4 LT |
119 | error = -EACCES; |
120 | goto out; | |
121 | } | |
122 | no_nice = security_task_setnice(p, niceval); | |
123 | if (no_nice) { | |
124 | error = no_nice; | |
125 | goto out; | |
126 | } | |
127 | if (error == -ESRCH) | |
128 | error = 0; | |
129 | set_user_nice(p, niceval); | |
130 | out: | |
131 | return error; | |
132 | } | |
133 | ||
134 | asmlinkage long sys_setpriority(int which, int who, int niceval) | |
135 | { | |
136 | struct task_struct *g, *p; | |
137 | struct user_struct *user; | |
138 | int error = -EINVAL; | |
41487c65 | 139 | struct pid *pgrp; |
1da177e4 | 140 | |
3e88c553 | 141 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
142 | goto out; |
143 | ||
144 | /* normalize: avoid signed division (rounding problems) */ | |
145 | error = -ESRCH; | |
146 | if (niceval < -20) | |
147 | niceval = -20; | |
148 | if (niceval > 19) | |
149 | niceval = 19; | |
150 | ||
151 | read_lock(&tasklist_lock); | |
152 | switch (which) { | |
153 | case PRIO_PROCESS: | |
41487c65 | 154 | if (who) |
228ebcbe | 155 | p = find_task_by_vpid(who); |
41487c65 EB |
156 | else |
157 | p = current; | |
1da177e4 LT |
158 | if (p) |
159 | error = set_one_prio(p, niceval, error); | |
160 | break; | |
161 | case PRIO_PGRP: | |
41487c65 | 162 | if (who) |
b488893a | 163 | pgrp = find_vpid(who); |
41487c65 EB |
164 | else |
165 | pgrp = task_pgrp(current); | |
166 | do_each_pid_task(pgrp, PIDTYPE_PGID, p) { | |
1da177e4 | 167 | error = set_one_prio(p, niceval, error); |
41487c65 | 168 | } while_each_pid_task(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
169 | break; |
170 | case PRIO_USER: | |
171 | user = current->user; | |
172 | if (!who) | |
173 | who = current->uid; | |
174 | else | |
175 | if ((who != current->uid) && !(user = find_user(who))) | |
176 | goto out_unlock; /* No processes for this user */ | |
177 | ||
178 | do_each_thread(g, p) | |
179 | if (p->uid == who) | |
180 | error = set_one_prio(p, niceval, error); | |
181 | while_each_thread(g, p); | |
182 | if (who != current->uid) | |
183 | free_uid(user); /* For find_user() */ | |
184 | break; | |
185 | } | |
186 | out_unlock: | |
187 | read_unlock(&tasklist_lock); | |
188 | out: | |
189 | return error; | |
190 | } | |
191 | ||
192 | /* | |
193 | * Ugh. To avoid negative return values, "getpriority()" will | |
194 | * not return the normal nice-value, but a negated value that | |
195 | * has been offset by 20 (ie it returns 40..1 instead of -20..19) | |
196 | * to stay compatible. | |
197 | */ | |
198 | asmlinkage long sys_getpriority(int which, int who) | |
199 | { | |
200 | struct task_struct *g, *p; | |
201 | struct user_struct *user; | |
202 | long niceval, retval = -ESRCH; | |
41487c65 | 203 | struct pid *pgrp; |
1da177e4 | 204 | |
3e88c553 | 205 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
206 | return -EINVAL; |
207 | ||
208 | read_lock(&tasklist_lock); | |
209 | switch (which) { | |
210 | case PRIO_PROCESS: | |
41487c65 | 211 | if (who) |
228ebcbe | 212 | p = find_task_by_vpid(who); |
41487c65 EB |
213 | else |
214 | p = current; | |
1da177e4 LT |
215 | if (p) { |
216 | niceval = 20 - task_nice(p); | |
217 | if (niceval > retval) | |
218 | retval = niceval; | |
219 | } | |
220 | break; | |
221 | case PRIO_PGRP: | |
41487c65 | 222 | if (who) |
b488893a | 223 | pgrp = find_vpid(who); |
41487c65 EB |
224 | else |
225 | pgrp = task_pgrp(current); | |
226 | do_each_pid_task(pgrp, PIDTYPE_PGID, p) { | |
1da177e4 LT |
227 | niceval = 20 - task_nice(p); |
228 | if (niceval > retval) | |
229 | retval = niceval; | |
41487c65 | 230 | } while_each_pid_task(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
231 | break; |
232 | case PRIO_USER: | |
233 | user = current->user; | |
234 | if (!who) | |
235 | who = current->uid; | |
236 | else | |
237 | if ((who != current->uid) && !(user = find_user(who))) | |
238 | goto out_unlock; /* No processes for this user */ | |
239 | ||
240 | do_each_thread(g, p) | |
241 | if (p->uid == who) { | |
242 | niceval = 20 - task_nice(p); | |
243 | if (niceval > retval) | |
244 | retval = niceval; | |
245 | } | |
246 | while_each_thread(g, p); | |
247 | if (who != current->uid) | |
248 | free_uid(user); /* for find_user() */ | |
249 | break; | |
250 | } | |
251 | out_unlock: | |
252 | read_unlock(&tasklist_lock); | |
253 | ||
254 | return retval; | |
255 | } | |
256 | ||
e4c94330 EB |
257 | /** |
258 | * emergency_restart - reboot the system | |
259 | * | |
260 | * Without shutting down any hardware or taking any locks | |
261 | * reboot the system. This is called when we know we are in | |
262 | * trouble so this is our best effort to reboot. This is | |
263 | * safe to call in interrupt context. | |
264 | */ | |
7c903473 EB |
265 | void emergency_restart(void) |
266 | { | |
267 | machine_emergency_restart(); | |
268 | } | |
269 | EXPORT_SYMBOL_GPL(emergency_restart); | |
270 | ||
83cc5ed3 | 271 | static void kernel_restart_prepare(char *cmd) |
4a00ea1e | 272 | { |
e041c683 | 273 | blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd); |
4a00ea1e | 274 | system_state = SYSTEM_RESTART; |
4a00ea1e | 275 | device_shutdown(); |
58b3b71d | 276 | sysdev_shutdown(); |
e4c94330 | 277 | } |
1e5d5331 RD |
278 | |
279 | /** | |
280 | * kernel_restart - reboot the system | |
281 | * @cmd: pointer to buffer containing command to execute for restart | |
b8887e6e | 282 | * or %NULL |
1e5d5331 RD |
283 | * |
284 | * Shutdown everything and perform a clean reboot. | |
285 | * This is not safe to call in interrupt context. | |
286 | */ | |
e4c94330 EB |
287 | void kernel_restart(char *cmd) |
288 | { | |
289 | kernel_restart_prepare(cmd); | |
756184b7 | 290 | if (!cmd) |
4a00ea1e | 291 | printk(KERN_EMERG "Restarting system.\n"); |
756184b7 | 292 | else |
4a00ea1e | 293 | printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd); |
4a00ea1e EB |
294 | machine_restart(cmd); |
295 | } | |
296 | EXPORT_SYMBOL_GPL(kernel_restart); | |
297 | ||
e4c94330 EB |
298 | /** |
299 | * kernel_kexec - reboot the system | |
300 | * | |
301 | * Move into place and start executing a preloaded standalone | |
302 | * executable. If nothing was preloaded return an error. | |
303 | */ | |
83cc5ed3 | 304 | static void kernel_kexec(void) |
4a00ea1e EB |
305 | { |
306 | #ifdef CONFIG_KEXEC | |
307 | struct kimage *image; | |
4bb8089c | 308 | image = xchg(&kexec_image, NULL); |
756184b7 | 309 | if (!image) |
4a00ea1e | 310 | return; |
e4c94330 | 311 | kernel_restart_prepare(NULL); |
4a00ea1e EB |
312 | printk(KERN_EMERG "Starting new kernel\n"); |
313 | machine_shutdown(); | |
314 | machine_kexec(image); | |
315 | #endif | |
316 | } | |
4a00ea1e | 317 | |
4ef7229f | 318 | static void kernel_shutdown_prepare(enum system_states state) |
729b4d4c | 319 | { |
e041c683 | 320 | blocking_notifier_call_chain(&reboot_notifier_list, |
729b4d4c AS |
321 | (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL); |
322 | system_state = state; | |
323 | device_shutdown(); | |
324 | } | |
e4c94330 EB |
325 | /** |
326 | * kernel_halt - halt the system | |
327 | * | |
328 | * Shutdown everything and perform a clean system halt. | |
329 | */ | |
e4c94330 EB |
330 | void kernel_halt(void) |
331 | { | |
729b4d4c | 332 | kernel_shutdown_prepare(SYSTEM_HALT); |
58b3b71d | 333 | sysdev_shutdown(); |
4a00ea1e EB |
334 | printk(KERN_EMERG "System halted.\n"); |
335 | machine_halt(); | |
336 | } | |
729b4d4c | 337 | |
4a00ea1e EB |
338 | EXPORT_SYMBOL_GPL(kernel_halt); |
339 | ||
e4c94330 EB |
340 | /** |
341 | * kernel_power_off - power_off the system | |
342 | * | |
343 | * Shutdown everything and perform a clean system power_off. | |
344 | */ | |
e4c94330 EB |
345 | void kernel_power_off(void) |
346 | { | |
729b4d4c | 347 | kernel_shutdown_prepare(SYSTEM_POWER_OFF); |
bd804eba RW |
348 | if (pm_power_off_prepare) |
349 | pm_power_off_prepare(); | |
4047727e | 350 | disable_nonboot_cpus(); |
58b3b71d | 351 | sysdev_shutdown(); |
4a00ea1e EB |
352 | printk(KERN_EMERG "Power down.\n"); |
353 | machine_power_off(); | |
354 | } | |
355 | EXPORT_SYMBOL_GPL(kernel_power_off); | |
1da177e4 LT |
356 | /* |
357 | * Reboot system call: for obvious reasons only root may call it, | |
358 | * and even root needs to set up some magic numbers in the registers | |
359 | * so that some mistake won't make this reboot the whole machine. | |
360 | * You can also set the meaning of the ctrl-alt-del-key here. | |
361 | * | |
362 | * reboot doesn't sync: do that yourself before calling this. | |
363 | */ | |
364 | asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user * arg) | |
365 | { | |
366 | char buffer[256]; | |
367 | ||
368 | /* We only trust the superuser with rebooting the system. */ | |
369 | if (!capable(CAP_SYS_BOOT)) | |
370 | return -EPERM; | |
371 | ||
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; | |
379 | ||
5e38291d EB |
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. | |
382 | */ | |
383 | if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off) | |
384 | cmd = LINUX_REBOOT_CMD_HALT; | |
385 | ||
1da177e4 LT |
386 | lock_kernel(); |
387 | switch (cmd) { | |
388 | case LINUX_REBOOT_CMD_RESTART: | |
4a00ea1e | 389 | kernel_restart(NULL); |
1da177e4 LT |
390 | break; |
391 | ||
392 | case LINUX_REBOOT_CMD_CAD_ON: | |
393 | C_A_D = 1; | |
394 | break; | |
395 | ||
396 | case LINUX_REBOOT_CMD_CAD_OFF: | |
397 | C_A_D = 0; | |
398 | break; | |
399 | ||
400 | case LINUX_REBOOT_CMD_HALT: | |
4a00ea1e | 401 | kernel_halt(); |
1da177e4 LT |
402 | unlock_kernel(); |
403 | do_exit(0); | |
404 | break; | |
405 | ||
406 | case LINUX_REBOOT_CMD_POWER_OFF: | |
4a00ea1e | 407 | kernel_power_off(); |
1da177e4 LT |
408 | unlock_kernel(); |
409 | do_exit(0); | |
410 | break; | |
411 | ||
412 | case LINUX_REBOOT_CMD_RESTART2: | |
413 | if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) { | |
414 | unlock_kernel(); | |
415 | return -EFAULT; | |
416 | } | |
417 | buffer[sizeof(buffer) - 1] = '\0'; | |
418 | ||
4a00ea1e | 419 | kernel_restart(buffer); |
1da177e4 LT |
420 | break; |
421 | ||
dc009d92 | 422 | case LINUX_REBOOT_CMD_KEXEC: |
4a00ea1e EB |
423 | kernel_kexec(); |
424 | unlock_kernel(); | |
425 | return -EINVAL; | |
426 | ||
b0cb1a19 | 427 | #ifdef CONFIG_HIBERNATION |
1da177e4 LT |
428 | case LINUX_REBOOT_CMD_SW_SUSPEND: |
429 | { | |
a3d25c27 | 430 | int ret = hibernate(); |
1da177e4 LT |
431 | unlock_kernel(); |
432 | return ret; | |
433 | } | |
434 | #endif | |
435 | ||
436 | default: | |
437 | unlock_kernel(); | |
438 | return -EINVAL; | |
439 | } | |
440 | unlock_kernel(); | |
441 | return 0; | |
442 | } | |
443 | ||
65f27f38 | 444 | static void deferred_cad(struct work_struct *dummy) |
1da177e4 | 445 | { |
abcd9e51 | 446 | kernel_restart(NULL); |
1da177e4 LT |
447 | } |
448 | ||
449 | /* | |
450 | * This function gets called by ctrl-alt-del - ie the keyboard interrupt. | |
451 | * As it's called within an interrupt, it may NOT sync: the only choice | |
452 | * is whether to reboot at once, or just ignore the ctrl-alt-del. | |
453 | */ | |
454 | void ctrl_alt_del(void) | |
455 | { | |
65f27f38 | 456 | static DECLARE_WORK(cad_work, deferred_cad); |
1da177e4 LT |
457 | |
458 | if (C_A_D) | |
459 | schedule_work(&cad_work); | |
460 | else | |
9ec52099 | 461 | kill_cad_pid(SIGINT, 1); |
1da177e4 LT |
462 | } |
463 | ||
1da177e4 LT |
464 | /* |
465 | * Unprivileged users may change the real gid to the effective gid | |
466 | * or vice versa. (BSD-style) | |
467 | * | |
468 | * If you set the real gid at all, or set the effective gid to a value not | |
469 | * equal to the real gid, then the saved gid is set to the new effective gid. | |
470 | * | |
471 | * This makes it possible for a setgid program to completely drop its | |
472 | * privileges, which is often a useful assertion to make when you are doing | |
473 | * a security audit over a program. | |
474 | * | |
475 | * The general idea is that a program which uses just setregid() will be | |
476 | * 100% compatible with BSD. A program which uses just setgid() will be | |
477 | * 100% compatible with POSIX with saved IDs. | |
478 | * | |
479 | * SMP: There are not races, the GIDs are checked only by filesystem | |
480 | * operations (as far as semantic preservation is concerned). | |
481 | */ | |
482 | asmlinkage long sys_setregid(gid_t rgid, gid_t egid) | |
483 | { | |
484 | int old_rgid = current->gid; | |
485 | int old_egid = current->egid; | |
486 | int new_rgid = old_rgid; | |
487 | int new_egid = old_egid; | |
488 | int retval; | |
489 | ||
490 | retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE); | |
491 | if (retval) | |
492 | return retval; | |
493 | ||
494 | if (rgid != (gid_t) -1) { | |
495 | if ((old_rgid == rgid) || | |
496 | (current->egid==rgid) || | |
497 | capable(CAP_SETGID)) | |
498 | new_rgid = rgid; | |
499 | else | |
500 | return -EPERM; | |
501 | } | |
502 | if (egid != (gid_t) -1) { | |
503 | if ((old_rgid == egid) || | |
504 | (current->egid == egid) || | |
505 | (current->sgid == egid) || | |
506 | capable(CAP_SETGID)) | |
507 | new_egid = egid; | |
756184b7 | 508 | else |
1da177e4 | 509 | return -EPERM; |
1da177e4 | 510 | } |
756184b7 | 511 | if (new_egid != old_egid) { |
6c5d5238 | 512 | set_dumpable(current->mm, suid_dumpable); |
d59dd462 | 513 | smp_wmb(); |
1da177e4 LT |
514 | } |
515 | if (rgid != (gid_t) -1 || | |
516 | (egid != (gid_t) -1 && egid != old_rgid)) | |
517 | current->sgid = new_egid; | |
518 | current->fsgid = new_egid; | |
519 | current->egid = new_egid; | |
520 | current->gid = new_rgid; | |
521 | key_fsgid_changed(current); | |
9f46080c | 522 | proc_id_connector(current, PROC_EVENT_GID); |
1da177e4 LT |
523 | return 0; |
524 | } | |
525 | ||
526 | /* | |
527 | * setgid() is implemented like SysV w/ SAVED_IDS | |
528 | * | |
529 | * SMP: Same implicit races as above. | |
530 | */ | |
531 | asmlinkage long sys_setgid(gid_t gid) | |
532 | { | |
533 | int old_egid = current->egid; | |
534 | int retval; | |
535 | ||
536 | retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID); | |
537 | if (retval) | |
538 | return retval; | |
539 | ||
756184b7 CP |
540 | if (capable(CAP_SETGID)) { |
541 | if (old_egid != gid) { | |
6c5d5238 | 542 | set_dumpable(current->mm, suid_dumpable); |
d59dd462 | 543 | smp_wmb(); |
1da177e4 LT |
544 | } |
545 | current->gid = current->egid = current->sgid = current->fsgid = gid; | |
756184b7 CP |
546 | } else if ((gid == current->gid) || (gid == current->sgid)) { |
547 | if (old_egid != gid) { | |
6c5d5238 | 548 | set_dumpable(current->mm, suid_dumpable); |
d59dd462 | 549 | smp_wmb(); |
1da177e4 LT |
550 | } |
551 | current->egid = current->fsgid = gid; | |
552 | } | |
553 | else | |
554 | return -EPERM; | |
555 | ||
556 | key_fsgid_changed(current); | |
9f46080c | 557 | proc_id_connector(current, PROC_EVENT_GID); |
1da177e4 LT |
558 | return 0; |
559 | } | |
560 | ||
561 | static int set_user(uid_t new_ruid, int dumpclear) | |
562 | { | |
563 | struct user_struct *new_user; | |
564 | ||
acce292c | 565 | new_user = alloc_uid(current->nsproxy->user_ns, new_ruid); |
1da177e4 LT |
566 | if (!new_user) |
567 | return -EAGAIN; | |
568 | ||
569 | if (atomic_read(&new_user->processes) >= | |
570 | current->signal->rlim[RLIMIT_NPROC].rlim_cur && | |
acce292c | 571 | new_user != current->nsproxy->user_ns->root_user) { |
1da177e4 LT |
572 | free_uid(new_user); |
573 | return -EAGAIN; | |
574 | } | |
575 | ||
576 | switch_uid(new_user); | |
577 | ||
756184b7 | 578 | if (dumpclear) { |
6c5d5238 | 579 | set_dumpable(current->mm, suid_dumpable); |
d59dd462 | 580 | smp_wmb(); |
1da177e4 LT |
581 | } |
582 | current->uid = new_ruid; | |
583 | return 0; | |
584 | } | |
585 | ||
586 | /* | |
587 | * Unprivileged users may change the real uid to the effective uid | |
588 | * or vice versa. (BSD-style) | |
589 | * | |
590 | * If you set the real uid at all, or set the effective uid to a value not | |
591 | * equal to the real uid, then the saved uid is set to the new effective uid. | |
592 | * | |
593 | * This makes it possible for a setuid program to completely drop its | |
594 | * privileges, which is often a useful assertion to make when you are doing | |
595 | * a security audit over a program. | |
596 | * | |
597 | * The general idea is that a program which uses just setreuid() will be | |
598 | * 100% compatible with BSD. A program which uses just setuid() will be | |
599 | * 100% compatible with POSIX with saved IDs. | |
600 | */ | |
601 | asmlinkage long sys_setreuid(uid_t ruid, uid_t euid) | |
602 | { | |
603 | int old_ruid, old_euid, old_suid, new_ruid, new_euid; | |
604 | int retval; | |
605 | ||
606 | retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE); | |
607 | if (retval) | |
608 | return retval; | |
609 | ||
610 | new_ruid = old_ruid = current->uid; | |
611 | new_euid = old_euid = current->euid; | |
612 | old_suid = current->suid; | |
613 | ||
614 | if (ruid != (uid_t) -1) { | |
615 | new_ruid = ruid; | |
616 | if ((old_ruid != ruid) && | |
617 | (current->euid != ruid) && | |
618 | !capable(CAP_SETUID)) | |
619 | return -EPERM; | |
620 | } | |
621 | ||
622 | if (euid != (uid_t) -1) { | |
623 | new_euid = euid; | |
624 | if ((old_ruid != euid) && | |
625 | (current->euid != euid) && | |
626 | (current->suid != euid) && | |
627 | !capable(CAP_SETUID)) | |
628 | return -EPERM; | |
629 | } | |
630 | ||
631 | if (new_ruid != old_ruid && set_user(new_ruid, new_euid != old_euid) < 0) | |
632 | return -EAGAIN; | |
633 | ||
756184b7 | 634 | if (new_euid != old_euid) { |
6c5d5238 | 635 | set_dumpable(current->mm, suid_dumpable); |
d59dd462 | 636 | smp_wmb(); |
1da177e4 LT |
637 | } |
638 | current->fsuid = current->euid = new_euid; | |
639 | if (ruid != (uid_t) -1 || | |
640 | (euid != (uid_t) -1 && euid != old_ruid)) | |
641 | current->suid = current->euid; | |
642 | current->fsuid = current->euid; | |
643 | ||
644 | key_fsuid_changed(current); | |
9f46080c | 645 | proc_id_connector(current, PROC_EVENT_UID); |
1da177e4 LT |
646 | |
647 | return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RE); | |
648 | } | |
649 | ||
650 | ||
651 | ||
652 | /* | |
653 | * setuid() is implemented like SysV with SAVED_IDS | |
654 | * | |
655 | * Note that SAVED_ID's is deficient in that a setuid root program | |
656 | * like sendmail, for example, cannot set its uid to be a normal | |
657 | * user and then switch back, because if you're root, setuid() sets | |
658 | * the saved uid too. If you don't like this, blame the bright people | |
659 | * in the POSIX committee and/or USG. Note that the BSD-style setreuid() | |
660 | * will allow a root program to temporarily drop privileges and be able to | |
661 | * regain them by swapping the real and effective uid. | |
662 | */ | |
663 | asmlinkage long sys_setuid(uid_t uid) | |
664 | { | |
665 | int old_euid = current->euid; | |
a09c17a6 | 666 | int old_ruid, old_suid, new_suid; |
1da177e4 LT |
667 | int retval; |
668 | ||
669 | retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID); | |
670 | if (retval) | |
671 | return retval; | |
672 | ||
a09c17a6 | 673 | old_ruid = current->uid; |
1da177e4 LT |
674 | old_suid = current->suid; |
675 | new_suid = old_suid; | |
676 | ||
677 | if (capable(CAP_SETUID)) { | |
678 | if (uid != old_ruid && set_user(uid, old_euid != uid) < 0) | |
679 | return -EAGAIN; | |
680 | new_suid = uid; | |
681 | } else if ((uid != current->uid) && (uid != new_suid)) | |
682 | return -EPERM; | |
683 | ||
756184b7 | 684 | if (old_euid != uid) { |
6c5d5238 | 685 | set_dumpable(current->mm, suid_dumpable); |
d59dd462 | 686 | smp_wmb(); |
1da177e4 LT |
687 | } |
688 | current->fsuid = current->euid = uid; | |
689 | current->suid = new_suid; | |
690 | ||
691 | key_fsuid_changed(current); | |
9f46080c | 692 | proc_id_connector(current, PROC_EVENT_UID); |
1da177e4 LT |
693 | |
694 | return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_ID); | |
695 | } | |
696 | ||
697 | ||
698 | /* | |
699 | * This function implements a generic ability to update ruid, euid, | |
700 | * and suid. This allows you to implement the 4.4 compatible seteuid(). | |
701 | */ | |
702 | asmlinkage long sys_setresuid(uid_t ruid, uid_t euid, uid_t suid) | |
703 | { | |
704 | int old_ruid = current->uid; | |
705 | int old_euid = current->euid; | |
706 | int old_suid = current->suid; | |
707 | int retval; | |
708 | ||
709 | retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES); | |
710 | if (retval) | |
711 | return retval; | |
712 | ||
713 | if (!capable(CAP_SETUID)) { | |
714 | if ((ruid != (uid_t) -1) && (ruid != current->uid) && | |
715 | (ruid != current->euid) && (ruid != current->suid)) | |
716 | return -EPERM; | |
717 | if ((euid != (uid_t) -1) && (euid != current->uid) && | |
718 | (euid != current->euid) && (euid != current->suid)) | |
719 | return -EPERM; | |
720 | if ((suid != (uid_t) -1) && (suid != current->uid) && | |
721 | (suid != current->euid) && (suid != current->suid)) | |
722 | return -EPERM; | |
723 | } | |
724 | if (ruid != (uid_t) -1) { | |
725 | if (ruid != current->uid && set_user(ruid, euid != current->euid) < 0) | |
726 | return -EAGAIN; | |
727 | } | |
728 | if (euid != (uid_t) -1) { | |
756184b7 | 729 | if (euid != current->euid) { |
6c5d5238 | 730 | set_dumpable(current->mm, suid_dumpable); |
d59dd462 | 731 | smp_wmb(); |
1da177e4 LT |
732 | } |
733 | current->euid = euid; | |
734 | } | |
735 | current->fsuid = current->euid; | |
736 | if (suid != (uid_t) -1) | |
737 | current->suid = suid; | |
738 | ||
739 | key_fsuid_changed(current); | |
9f46080c | 740 | proc_id_connector(current, PROC_EVENT_UID); |
1da177e4 LT |
741 | |
742 | return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RES); | |
743 | } | |
744 | ||
745 | asmlinkage long sys_getresuid(uid_t __user *ruid, uid_t __user *euid, uid_t __user *suid) | |
746 | { | |
747 | int retval; | |
748 | ||
749 | if (!(retval = put_user(current->uid, ruid)) && | |
750 | !(retval = put_user(current->euid, euid))) | |
751 | retval = put_user(current->suid, suid); | |
752 | ||
753 | return retval; | |
754 | } | |
755 | ||
756 | /* | |
757 | * Same as above, but for rgid, egid, sgid. | |
758 | */ | |
759 | asmlinkage long sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid) | |
760 | { | |
761 | int retval; | |
762 | ||
763 | retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES); | |
764 | if (retval) | |
765 | return retval; | |
766 | ||
767 | if (!capable(CAP_SETGID)) { | |
768 | if ((rgid != (gid_t) -1) && (rgid != current->gid) && | |
769 | (rgid != current->egid) && (rgid != current->sgid)) | |
770 | return -EPERM; | |
771 | if ((egid != (gid_t) -1) && (egid != current->gid) && | |
772 | (egid != current->egid) && (egid != current->sgid)) | |
773 | return -EPERM; | |
774 | if ((sgid != (gid_t) -1) && (sgid != current->gid) && | |
775 | (sgid != current->egid) && (sgid != current->sgid)) | |
776 | return -EPERM; | |
777 | } | |
778 | if (egid != (gid_t) -1) { | |
756184b7 | 779 | if (egid != current->egid) { |
6c5d5238 | 780 | set_dumpable(current->mm, suid_dumpable); |
d59dd462 | 781 | smp_wmb(); |
1da177e4 LT |
782 | } |
783 | current->egid = egid; | |
784 | } | |
785 | current->fsgid = current->egid; | |
786 | if (rgid != (gid_t) -1) | |
787 | current->gid = rgid; | |
788 | if (sgid != (gid_t) -1) | |
789 | current->sgid = sgid; | |
790 | ||
791 | key_fsgid_changed(current); | |
9f46080c | 792 | proc_id_connector(current, PROC_EVENT_GID); |
1da177e4 LT |
793 | return 0; |
794 | } | |
795 | ||
796 | asmlinkage long sys_getresgid(gid_t __user *rgid, gid_t __user *egid, gid_t __user *sgid) | |
797 | { | |
798 | int retval; | |
799 | ||
800 | if (!(retval = put_user(current->gid, rgid)) && | |
801 | !(retval = put_user(current->egid, egid))) | |
802 | retval = put_user(current->sgid, sgid); | |
803 | ||
804 | return retval; | |
805 | } | |
806 | ||
807 | ||
808 | /* | |
809 | * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This | |
810 | * is used for "access()" and for the NFS daemon (letting nfsd stay at | |
811 | * whatever uid it wants to). It normally shadows "euid", except when | |
812 | * explicitly set by setfsuid() or for access.. | |
813 | */ | |
814 | asmlinkage long sys_setfsuid(uid_t uid) | |
815 | { | |
816 | int old_fsuid; | |
817 | ||
818 | old_fsuid = current->fsuid; | |
819 | if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS)) | |
820 | return old_fsuid; | |
821 | ||
822 | if (uid == current->uid || uid == current->euid || | |
823 | uid == current->suid || uid == current->fsuid || | |
756184b7 CP |
824 | capable(CAP_SETUID)) { |
825 | if (uid != old_fsuid) { | |
6c5d5238 | 826 | set_dumpable(current->mm, suid_dumpable); |
d59dd462 | 827 | smp_wmb(); |
1da177e4 LT |
828 | } |
829 | current->fsuid = uid; | |
830 | } | |
831 | ||
832 | key_fsuid_changed(current); | |
9f46080c | 833 | proc_id_connector(current, PROC_EVENT_UID); |
1da177e4 LT |
834 | |
835 | security_task_post_setuid(old_fsuid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS); | |
836 | ||
837 | return old_fsuid; | |
838 | } | |
839 | ||
840 | /* | |
f42df9e6 | 841 | * Samma på svenska.. |
1da177e4 LT |
842 | */ |
843 | asmlinkage long sys_setfsgid(gid_t gid) | |
844 | { | |
845 | int old_fsgid; | |
846 | ||
847 | old_fsgid = current->fsgid; | |
848 | if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS)) | |
849 | return old_fsgid; | |
850 | ||
851 | if (gid == current->gid || gid == current->egid || | |
852 | gid == current->sgid || gid == current->fsgid || | |
756184b7 CP |
853 | capable(CAP_SETGID)) { |
854 | if (gid != old_fsgid) { | |
6c5d5238 | 855 | set_dumpable(current->mm, suid_dumpable); |
d59dd462 | 856 | smp_wmb(); |
1da177e4 LT |
857 | } |
858 | current->fsgid = gid; | |
859 | key_fsgid_changed(current); | |
9f46080c | 860 | proc_id_connector(current, PROC_EVENT_GID); |
1da177e4 LT |
861 | } |
862 | return old_fsgid; | |
863 | } | |
864 | ||
865 | asmlinkage long sys_times(struct tms __user * tbuf) | |
866 | { | |
867 | /* | |
868 | * In the SMP world we might just be unlucky and have one of | |
869 | * the times increment as we use it. Since the value is an | |
870 | * atomically safe type this is just fine. Conceptually its | |
871 | * as if the syscall took an instant longer to occur. | |
872 | */ | |
873 | if (tbuf) { | |
874 | struct tms tmp; | |
35f5cad8 ON |
875 | struct task_struct *tsk = current; |
876 | struct task_struct *t; | |
1da177e4 LT |
877 | cputime_t utime, stime, cutime, cstime; |
878 | ||
7d7185c8 | 879 | spin_lock_irq(&tsk->sighand->siglock); |
35f5cad8 ON |
880 | utime = tsk->signal->utime; |
881 | stime = tsk->signal->stime; | |
882 | t = tsk; | |
883 | do { | |
884 | utime = cputime_add(utime, t->utime); | |
885 | stime = cputime_add(stime, t->stime); | |
886 | t = next_thread(t); | |
887 | } while (t != tsk); | |
888 | ||
35f5cad8 ON |
889 | cutime = tsk->signal->cutime; |
890 | cstime = tsk->signal->cstime; | |
891 | spin_unlock_irq(&tsk->sighand->siglock); | |
1da177e4 LT |
892 | |
893 | tmp.tms_utime = cputime_to_clock_t(utime); | |
894 | tmp.tms_stime = cputime_to_clock_t(stime); | |
895 | tmp.tms_cutime = cputime_to_clock_t(cutime); | |
896 | tmp.tms_cstime = cputime_to_clock_t(cstime); | |
897 | if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) | |
898 | return -EFAULT; | |
899 | } | |
900 | return (long) jiffies_64_to_clock_t(get_jiffies_64()); | |
901 | } | |
902 | ||
903 | /* | |
904 | * This needs some heavy checking ... | |
905 | * I just haven't the stomach for it. I also don't fully | |
906 | * understand sessions/pgrp etc. Let somebody who does explain it. | |
907 | * | |
908 | * OK, I think I have the protection semantics right.... this is really | |
909 | * only important on a multi-user system anyway, to make sure one user | |
910 | * can't send a signal to a process owned by another. -TYT, 12/12/91 | |
911 | * | |
912 | * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. | |
913 | * LBT 04.03.94 | |
914 | */ | |
1da177e4 LT |
915 | asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) |
916 | { | |
917 | struct task_struct *p; | |
ee0acf90 | 918 | struct task_struct *group_leader = current->group_leader; |
4e021306 ON |
919 | struct pid *pgrp; |
920 | int err; | |
1da177e4 LT |
921 | |
922 | if (!pid) | |
b488893a | 923 | pid = task_pid_vnr(group_leader); |
1da177e4 LT |
924 | if (!pgid) |
925 | pgid = pid; | |
926 | if (pgid < 0) | |
927 | return -EINVAL; | |
928 | ||
929 | /* From this point forward we keep holding onto the tasklist lock | |
930 | * so that our parent does not change from under us. -DaveM | |
931 | */ | |
932 | write_lock_irq(&tasklist_lock); | |
933 | ||
934 | err = -ESRCH; | |
4e021306 | 935 | p = find_task_by_vpid(pid); |
1da177e4 LT |
936 | if (!p) |
937 | goto out; | |
938 | ||
939 | err = -EINVAL; | |
940 | if (!thread_group_leader(p)) | |
941 | goto out; | |
942 | ||
4e021306 | 943 | if (same_thread_group(p->real_parent, group_leader)) { |
1da177e4 | 944 | err = -EPERM; |
41487c65 | 945 | if (task_session(p) != task_session(group_leader)) |
1da177e4 LT |
946 | goto out; |
947 | err = -EACCES; | |
948 | if (p->did_exec) | |
949 | goto out; | |
950 | } else { | |
951 | err = -ESRCH; | |
ee0acf90 | 952 | if (p != group_leader) |
1da177e4 LT |
953 | goto out; |
954 | } | |
955 | ||
956 | err = -EPERM; | |
957 | if (p->signal->leader) | |
958 | goto out; | |
959 | ||
4e021306 | 960 | pgrp = task_pid(p); |
1da177e4 | 961 | if (pgid != pid) { |
b488893a | 962 | struct task_struct *g; |
1da177e4 | 963 | |
4e021306 ON |
964 | pgrp = find_vpid(pgid); |
965 | g = pid_task(pgrp, PIDTYPE_PGID); | |
41487c65 | 966 | if (!g || task_session(g) != task_session(group_leader)) |
f020bc46 | 967 | goto out; |
1da177e4 LT |
968 | } |
969 | ||
1da177e4 LT |
970 | err = security_task_setpgid(p, pgid); |
971 | if (err) | |
972 | goto out; | |
973 | ||
4e021306 | 974 | if (task_pgrp(p) != pgrp) { |
1da177e4 | 975 | detach_pid(p, PIDTYPE_PGID); |
4e021306 ON |
976 | attach_pid(p, PIDTYPE_PGID, pgrp); |
977 | set_task_pgrp(p, pid_nr(pgrp)); | |
1da177e4 LT |
978 | } |
979 | ||
980 | err = 0; | |
981 | out: | |
982 | /* All paths lead to here, thus we are safe. -DaveM */ | |
983 | write_unlock_irq(&tasklist_lock); | |
984 | return err; | |
985 | } | |
986 | ||
987 | asmlinkage long sys_getpgid(pid_t pid) | |
988 | { | |
756184b7 | 989 | if (!pid) |
b488893a | 990 | return task_pgrp_vnr(current); |
756184b7 | 991 | else { |
1da177e4 LT |
992 | int retval; |
993 | struct task_struct *p; | |
1da177e4 | 994 | |
b488893a | 995 | read_lock(&tasklist_lock); |
6c5f3e7b | 996 | p = find_task_by_vpid(pid); |
1da177e4 LT |
997 | retval = -ESRCH; |
998 | if (p) { | |
999 | retval = security_task_getpgid(p); | |
1000 | if (!retval) | |
6c5f3e7b | 1001 | retval = task_pgrp_vnr(p); |
1da177e4 LT |
1002 | } |
1003 | read_unlock(&tasklist_lock); | |
1004 | return retval; | |
1005 | } | |
1006 | } | |
1007 | ||
1008 | #ifdef __ARCH_WANT_SYS_GETPGRP | |
1009 | ||
1010 | asmlinkage long sys_getpgrp(void) | |
1011 | { | |
1012 | /* SMP - assuming writes are word atomic this is fine */ | |
b488893a | 1013 | return task_pgrp_vnr(current); |
1da177e4 LT |
1014 | } |
1015 | ||
1016 | #endif | |
1017 | ||
1018 | asmlinkage long sys_getsid(pid_t pid) | |
1019 | { | |
756184b7 | 1020 | if (!pid) |
b488893a | 1021 | return task_session_vnr(current); |
756184b7 | 1022 | else { |
1da177e4 LT |
1023 | int retval; |
1024 | struct task_struct *p; | |
1da177e4 | 1025 | |
ac9a8e3f ON |
1026 | rcu_read_lock(); |
1027 | p = find_task_by_vpid(pid); | |
1da177e4 | 1028 | retval = -ESRCH; |
756184b7 | 1029 | if (p) { |
1da177e4 LT |
1030 | retval = security_task_getsid(p); |
1031 | if (!retval) | |
ac9a8e3f | 1032 | retval = task_session_vnr(p); |
1da177e4 | 1033 | } |
ac9a8e3f | 1034 | rcu_read_unlock(); |
1da177e4 LT |
1035 | return retval; |
1036 | } | |
1037 | } | |
1038 | ||
1039 | asmlinkage long sys_setsid(void) | |
1040 | { | |
e19f247a | 1041 | struct task_struct *group_leader = current->group_leader; |
e4cc0a9c ON |
1042 | struct pid *sid = task_pid(group_leader); |
1043 | pid_t session = pid_vnr(sid); | |
1da177e4 LT |
1044 | int err = -EPERM; |
1045 | ||
1da177e4 | 1046 | write_lock_irq(&tasklist_lock); |
390e2ff0 EB |
1047 | /* Fail if I am already a session leader */ |
1048 | if (group_leader->signal->leader) | |
1049 | goto out; | |
1050 | ||
430c6231 ON |
1051 | /* Fail if a process group id already exists that equals the |
1052 | * proposed session id. | |
390e2ff0 | 1053 | */ |
6806aac6 | 1054 | if (pid_task(sid, PIDTYPE_PGID)) |
1da177e4 LT |
1055 | goto out; |
1056 | ||
e19f247a | 1057 | group_leader->signal->leader = 1; |
8520d7c7 | 1058 | __set_special_pids(sid); |
24ec839c PZ |
1059 | |
1060 | spin_lock(&group_leader->sighand->siglock); | |
e19f247a | 1061 | group_leader->signal->tty = NULL; |
24ec839c PZ |
1062 | spin_unlock(&group_leader->sighand->siglock); |
1063 | ||
e4cc0a9c | 1064 | err = session; |
1da177e4 LT |
1065 | out: |
1066 | write_unlock_irq(&tasklist_lock); | |
1da177e4 LT |
1067 | return err; |
1068 | } | |
1069 | ||
1070 | /* | |
1071 | * Supplementary group IDs | |
1072 | */ | |
1073 | ||
1074 | /* init to 2 - one for init_task, one to ensure it is never freed */ | |
1075 | struct group_info init_groups = { .usage = ATOMIC_INIT(2) }; | |
1076 | ||
1077 | struct group_info *groups_alloc(int gidsetsize) | |
1078 | { | |
1079 | struct group_info *group_info; | |
1080 | int nblocks; | |
1081 | int i; | |
1082 | ||
1083 | nblocks = (gidsetsize + NGROUPS_PER_BLOCK - 1) / NGROUPS_PER_BLOCK; | |
1084 | /* Make sure we always allocate at least one indirect block pointer */ | |
1085 | nblocks = nblocks ? : 1; | |
1086 | group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *), GFP_USER); | |
1087 | if (!group_info) | |
1088 | return NULL; | |
1089 | group_info->ngroups = gidsetsize; | |
1090 | group_info->nblocks = nblocks; | |
1091 | atomic_set(&group_info->usage, 1); | |
1092 | ||
756184b7 | 1093 | if (gidsetsize <= NGROUPS_SMALL) |
1da177e4 | 1094 | group_info->blocks[0] = group_info->small_block; |
756184b7 | 1095 | else { |
1da177e4 LT |
1096 | for (i = 0; i < nblocks; i++) { |
1097 | gid_t *b; | |
1098 | b = (void *)__get_free_page(GFP_USER); | |
1099 | if (!b) | |
1100 | goto out_undo_partial_alloc; | |
1101 | group_info->blocks[i] = b; | |
1102 | } | |
1103 | } | |
1104 | return group_info; | |
1105 | ||
1106 | out_undo_partial_alloc: | |
1107 | while (--i >= 0) { | |
1108 | free_page((unsigned long)group_info->blocks[i]); | |
1109 | } | |
1110 | kfree(group_info); | |
1111 | return NULL; | |
1112 | } | |
1113 | ||
1114 | EXPORT_SYMBOL(groups_alloc); | |
1115 | ||
1116 | void groups_free(struct group_info *group_info) | |
1117 | { | |
1118 | if (group_info->blocks[0] != group_info->small_block) { | |
1119 | int i; | |
1120 | for (i = 0; i < group_info->nblocks; i++) | |
1121 | free_page((unsigned long)group_info->blocks[i]); | |
1122 | } | |
1123 | kfree(group_info); | |
1124 | } | |
1125 | ||
1126 | EXPORT_SYMBOL(groups_free); | |
1127 | ||
1128 | /* export the group_info to a user-space array */ | |
1129 | static int groups_to_user(gid_t __user *grouplist, | |
1130 | struct group_info *group_info) | |
1131 | { | |
1132 | int i; | |
1bf47346 | 1133 | unsigned int count = group_info->ngroups; |
1da177e4 LT |
1134 | |
1135 | for (i = 0; i < group_info->nblocks; i++) { | |
1bf47346 ED |
1136 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
1137 | unsigned int len = cp_count * sizeof(*grouplist); | |
1da177e4 | 1138 | |
1bf47346 | 1139 | if (copy_to_user(grouplist, group_info->blocks[i], len)) |
1da177e4 LT |
1140 | return -EFAULT; |
1141 | ||
1bf47346 | 1142 | grouplist += NGROUPS_PER_BLOCK; |
1da177e4 LT |
1143 | count -= cp_count; |
1144 | } | |
1145 | return 0; | |
1146 | } | |
1147 | ||
1148 | /* fill a group_info from a user-space array - it must be allocated already */ | |
1149 | static int groups_from_user(struct group_info *group_info, | |
1150 | gid_t __user *grouplist) | |
756184b7 | 1151 | { |
1da177e4 | 1152 | int i; |
1bf47346 | 1153 | unsigned int count = group_info->ngroups; |
1da177e4 LT |
1154 | |
1155 | for (i = 0; i < group_info->nblocks; i++) { | |
1bf47346 ED |
1156 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
1157 | unsigned int len = cp_count * sizeof(*grouplist); | |
1da177e4 | 1158 | |
1bf47346 | 1159 | if (copy_from_user(group_info->blocks[i], grouplist, len)) |
1da177e4 LT |
1160 | return -EFAULT; |
1161 | ||
1bf47346 | 1162 | grouplist += NGROUPS_PER_BLOCK; |
1da177e4 LT |
1163 | count -= cp_count; |
1164 | } | |
1165 | return 0; | |
1166 | } | |
1167 | ||
ebe8b541 | 1168 | /* a simple Shell sort */ |
1da177e4 LT |
1169 | static void groups_sort(struct group_info *group_info) |
1170 | { | |
1171 | int base, max, stride; | |
1172 | int gidsetsize = group_info->ngroups; | |
1173 | ||
1174 | for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1) | |
1175 | ; /* nothing */ | |
1176 | stride /= 3; | |
1177 | ||
1178 | while (stride) { | |
1179 | max = gidsetsize - stride; | |
1180 | for (base = 0; base < max; base++) { | |
1181 | int left = base; | |
1182 | int right = left + stride; | |
1183 | gid_t tmp = GROUP_AT(group_info, right); | |
1184 | ||
1185 | while (left >= 0 && GROUP_AT(group_info, left) > tmp) { | |
1186 | GROUP_AT(group_info, right) = | |
1187 | GROUP_AT(group_info, left); | |
1188 | right = left; | |
1189 | left -= stride; | |
1190 | } | |
1191 | GROUP_AT(group_info, right) = tmp; | |
1192 | } | |
1193 | stride /= 3; | |
1194 | } | |
1195 | } | |
1196 | ||
1197 | /* a simple bsearch */ | |
3e30148c | 1198 | int groups_search(struct group_info *group_info, gid_t grp) |
1da177e4 | 1199 | { |
d74beb9f | 1200 | unsigned int left, right; |
1da177e4 LT |
1201 | |
1202 | if (!group_info) | |
1203 | return 0; | |
1204 | ||
1205 | left = 0; | |
1206 | right = group_info->ngroups; | |
1207 | while (left < right) { | |
d74beb9f | 1208 | unsigned int mid = (left+right)/2; |
1da177e4 LT |
1209 | int cmp = grp - GROUP_AT(group_info, mid); |
1210 | if (cmp > 0) | |
1211 | left = mid + 1; | |
1212 | else if (cmp < 0) | |
1213 | right = mid; | |
1214 | else | |
1215 | return 1; | |
1216 | } | |
1217 | return 0; | |
1218 | } | |
1219 | ||
1220 | /* validate and set current->group_info */ | |
1221 | int set_current_groups(struct group_info *group_info) | |
1222 | { | |
1223 | int retval; | |
1224 | struct group_info *old_info; | |
1225 | ||
1226 | retval = security_task_setgroups(group_info); | |
1227 | if (retval) | |
1228 | return retval; | |
1229 | ||
1230 | groups_sort(group_info); | |
1231 | get_group_info(group_info); | |
1232 | ||
1233 | task_lock(current); | |
1234 | old_info = current->group_info; | |
1235 | current->group_info = group_info; | |
1236 | task_unlock(current); | |
1237 | ||
1238 | put_group_info(old_info); | |
1239 | ||
1240 | return 0; | |
1241 | } | |
1242 | ||
1243 | EXPORT_SYMBOL(set_current_groups); | |
1244 | ||
1245 | asmlinkage long sys_getgroups(int gidsetsize, gid_t __user *grouplist) | |
1246 | { | |
1247 | int i = 0; | |
1248 | ||
1249 | /* | |
1250 | * SMP: Nobody else can change our grouplist. Thus we are | |
1251 | * safe. | |
1252 | */ | |
1253 | ||
1254 | if (gidsetsize < 0) | |
1255 | return -EINVAL; | |
1256 | ||
1257 | /* no need to grab task_lock here; it cannot change */ | |
1da177e4 LT |
1258 | i = current->group_info->ngroups; |
1259 | if (gidsetsize) { | |
1260 | if (i > gidsetsize) { | |
1261 | i = -EINVAL; | |
1262 | goto out; | |
1263 | } | |
1264 | if (groups_to_user(grouplist, current->group_info)) { | |
1265 | i = -EFAULT; | |
1266 | goto out; | |
1267 | } | |
1268 | } | |
1269 | out: | |
1da177e4 LT |
1270 | return i; |
1271 | } | |
1272 | ||
1273 | /* | |
1274 | * SMP: Our groups are copy-on-write. We can set them safely | |
1275 | * without another task interfering. | |
1276 | */ | |
1277 | ||
1278 | asmlinkage long sys_setgroups(int gidsetsize, gid_t __user *grouplist) | |
1279 | { | |
1280 | struct group_info *group_info; | |
1281 | int retval; | |
1282 | ||
1283 | if (!capable(CAP_SETGID)) | |
1284 | return -EPERM; | |
1285 | if ((unsigned)gidsetsize > NGROUPS_MAX) | |
1286 | return -EINVAL; | |
1287 | ||
1288 | group_info = groups_alloc(gidsetsize); | |
1289 | if (!group_info) | |
1290 | return -ENOMEM; | |
1291 | retval = groups_from_user(group_info, grouplist); | |
1292 | if (retval) { | |
1293 | put_group_info(group_info); | |
1294 | return retval; | |
1295 | } | |
1296 | ||
1297 | retval = set_current_groups(group_info); | |
1298 | put_group_info(group_info); | |
1299 | ||
1300 | return retval; | |
1301 | } | |
1302 | ||
1303 | /* | |
1304 | * Check whether we're fsgid/egid or in the supplemental group.. | |
1305 | */ | |
1306 | int in_group_p(gid_t grp) | |
1307 | { | |
1308 | int retval = 1; | |
756184b7 | 1309 | if (grp != current->fsgid) |
1da177e4 | 1310 | retval = groups_search(current->group_info, grp); |
1da177e4 LT |
1311 | return retval; |
1312 | } | |
1313 | ||
1314 | EXPORT_SYMBOL(in_group_p); | |
1315 | ||
1316 | int in_egroup_p(gid_t grp) | |
1317 | { | |
1318 | int retval = 1; | |
756184b7 | 1319 | if (grp != current->egid) |
1da177e4 | 1320 | retval = groups_search(current->group_info, grp); |
1da177e4 LT |
1321 | return retval; |
1322 | } | |
1323 | ||
1324 | EXPORT_SYMBOL(in_egroup_p); | |
1325 | ||
1326 | DECLARE_RWSEM(uts_sem); | |
1327 | ||
393b0725 DM |
1328 | EXPORT_SYMBOL(uts_sem); |
1329 | ||
1da177e4 LT |
1330 | asmlinkage long sys_newuname(struct new_utsname __user * name) |
1331 | { | |
1332 | int errno = 0; | |
1333 | ||
1334 | down_read(&uts_sem); | |
e9ff3990 | 1335 | if (copy_to_user(name, utsname(), sizeof *name)) |
1da177e4 LT |
1336 | errno = -EFAULT; |
1337 | up_read(&uts_sem); | |
1338 | return errno; | |
1339 | } | |
1340 | ||
1341 | asmlinkage long sys_sethostname(char __user *name, int len) | |
1342 | { | |
1343 | int errno; | |
1344 | char tmp[__NEW_UTS_LEN]; | |
1345 | ||
1346 | if (!capable(CAP_SYS_ADMIN)) | |
1347 | return -EPERM; | |
1348 | if (len < 0 || len > __NEW_UTS_LEN) | |
1349 | return -EINVAL; | |
1350 | down_write(&uts_sem); | |
1351 | errno = -EFAULT; | |
1352 | if (!copy_from_user(tmp, name, len)) { | |
e9ff3990 SH |
1353 | memcpy(utsname()->nodename, tmp, len); |
1354 | utsname()->nodename[len] = 0; | |
1da177e4 LT |
1355 | errno = 0; |
1356 | } | |
1357 | up_write(&uts_sem); | |
1358 | return errno; | |
1359 | } | |
1360 | ||
1361 | #ifdef __ARCH_WANT_SYS_GETHOSTNAME | |
1362 | ||
1363 | asmlinkage long sys_gethostname(char __user *name, int len) | |
1364 | { | |
1365 | int i, errno; | |
1366 | ||
1367 | if (len < 0) | |
1368 | return -EINVAL; | |
1369 | down_read(&uts_sem); | |
e9ff3990 | 1370 | i = 1 + strlen(utsname()->nodename); |
1da177e4 LT |
1371 | if (i > len) |
1372 | i = len; | |
1373 | errno = 0; | |
e9ff3990 | 1374 | if (copy_to_user(name, utsname()->nodename, i)) |
1da177e4 LT |
1375 | errno = -EFAULT; |
1376 | up_read(&uts_sem); | |
1377 | return errno; | |
1378 | } | |
1379 | ||
1380 | #endif | |
1381 | ||
1382 | /* | |
1383 | * Only setdomainname; getdomainname can be implemented by calling | |
1384 | * uname() | |
1385 | */ | |
1386 | asmlinkage long sys_setdomainname(char __user *name, int len) | |
1387 | { | |
1388 | int errno; | |
1389 | char tmp[__NEW_UTS_LEN]; | |
1390 | ||
1391 | if (!capable(CAP_SYS_ADMIN)) | |
1392 | return -EPERM; | |
1393 | if (len < 0 || len > __NEW_UTS_LEN) | |
1394 | return -EINVAL; | |
1395 | ||
1396 | down_write(&uts_sem); | |
1397 | errno = -EFAULT; | |
1398 | if (!copy_from_user(tmp, name, len)) { | |
e9ff3990 SH |
1399 | memcpy(utsname()->domainname, tmp, len); |
1400 | utsname()->domainname[len] = 0; | |
1da177e4 LT |
1401 | errno = 0; |
1402 | } | |
1403 | up_write(&uts_sem); | |
1404 | return errno; | |
1405 | } | |
1406 | ||
1407 | asmlinkage long sys_getrlimit(unsigned int resource, struct rlimit __user *rlim) | |
1408 | { | |
1409 | if (resource >= RLIM_NLIMITS) | |
1410 | return -EINVAL; | |
1411 | else { | |
1412 | struct rlimit value; | |
1413 | task_lock(current->group_leader); | |
1414 | value = current->signal->rlim[resource]; | |
1415 | task_unlock(current->group_leader); | |
1416 | return copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; | |
1417 | } | |
1418 | } | |
1419 | ||
1420 | #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT | |
1421 | ||
1422 | /* | |
1423 | * Back compatibility for getrlimit. Needed for some apps. | |
1424 | */ | |
1425 | ||
1426 | asmlinkage long sys_old_getrlimit(unsigned int resource, struct rlimit __user *rlim) | |
1427 | { | |
1428 | struct rlimit x; | |
1429 | if (resource >= RLIM_NLIMITS) | |
1430 | return -EINVAL; | |
1431 | ||
1432 | task_lock(current->group_leader); | |
1433 | x = current->signal->rlim[resource]; | |
1434 | task_unlock(current->group_leader); | |
756184b7 | 1435 | if (x.rlim_cur > 0x7FFFFFFF) |
1da177e4 | 1436 | x.rlim_cur = 0x7FFFFFFF; |
756184b7 | 1437 | if (x.rlim_max > 0x7FFFFFFF) |
1da177e4 LT |
1438 | x.rlim_max = 0x7FFFFFFF; |
1439 | return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0; | |
1440 | } | |
1441 | ||
1442 | #endif | |
1443 | ||
1444 | asmlinkage long sys_setrlimit(unsigned int resource, struct rlimit __user *rlim) | |
1445 | { | |
1446 | struct rlimit new_rlim, *old_rlim; | |
ec9e16ba | 1447 | unsigned long it_prof_secs; |
1da177e4 LT |
1448 | int retval; |
1449 | ||
1450 | if (resource >= RLIM_NLIMITS) | |
1451 | return -EINVAL; | |
ec9e16ba | 1452 | if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) |
1da177e4 | 1453 | return -EFAULT; |
ec9e16ba AM |
1454 | if (new_rlim.rlim_cur > new_rlim.rlim_max) |
1455 | return -EINVAL; | |
1da177e4 LT |
1456 | old_rlim = current->signal->rlim + resource; |
1457 | if ((new_rlim.rlim_max > old_rlim->rlim_max) && | |
1458 | !capable(CAP_SYS_RESOURCE)) | |
1459 | return -EPERM; | |
9cfe015a | 1460 | if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open) |
ec9e16ba | 1461 | return -EPERM; |
1da177e4 LT |
1462 | |
1463 | retval = security_task_setrlimit(resource, &new_rlim); | |
1464 | if (retval) | |
1465 | return retval; | |
1466 | ||
9926e4c7 TA |
1467 | if (resource == RLIMIT_CPU && new_rlim.rlim_cur == 0) { |
1468 | /* | |
1469 | * The caller is asking for an immediate RLIMIT_CPU | |
1470 | * expiry. But we use the zero value to mean "it was | |
1471 | * never set". So let's cheat and make it one second | |
1472 | * instead | |
1473 | */ | |
1474 | new_rlim.rlim_cur = 1; | |
1475 | } | |
1476 | ||
1da177e4 LT |
1477 | task_lock(current->group_leader); |
1478 | *old_rlim = new_rlim; | |
1479 | task_unlock(current->group_leader); | |
1480 | ||
ec9e16ba AM |
1481 | if (resource != RLIMIT_CPU) |
1482 | goto out; | |
d3561f78 AM |
1483 | |
1484 | /* | |
1485 | * RLIMIT_CPU handling. Note that the kernel fails to return an error | |
1486 | * code if it rejected the user's attempt to set RLIMIT_CPU. This is a | |
1487 | * very long-standing error, and fixing it now risks breakage of | |
1488 | * applications, so we live with it | |
1489 | */ | |
ec9e16ba AM |
1490 | if (new_rlim.rlim_cur == RLIM_INFINITY) |
1491 | goto out; | |
1492 | ||
1493 | it_prof_secs = cputime_to_secs(current->signal->it_prof_expires); | |
1494 | if (it_prof_secs == 0 || new_rlim.rlim_cur <= it_prof_secs) { | |
e0661111 AM |
1495 | unsigned long rlim_cur = new_rlim.rlim_cur; |
1496 | cputime_t cputime; | |
ec9e16ba | 1497 | |
e0661111 | 1498 | cputime = secs_to_cputime(rlim_cur); |
1da177e4 LT |
1499 | read_lock(&tasklist_lock); |
1500 | spin_lock_irq(¤t->sighand->siglock); | |
ec9e16ba | 1501 | set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL); |
1da177e4 LT |
1502 | spin_unlock_irq(¤t->sighand->siglock); |
1503 | read_unlock(&tasklist_lock); | |
1504 | } | |
ec9e16ba | 1505 | out: |
1da177e4 LT |
1506 | return 0; |
1507 | } | |
1508 | ||
1509 | /* | |
1510 | * It would make sense to put struct rusage in the task_struct, | |
1511 | * except that would make the task_struct be *really big*. After | |
1512 | * task_struct gets moved into malloc'ed memory, it would | |
1513 | * make sense to do this. It will make moving the rest of the information | |
1514 | * a lot simpler! (Which we're not doing right now because we're not | |
1515 | * measuring them yet). | |
1516 | * | |
1da177e4 LT |
1517 | * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
1518 | * races with threads incrementing their own counters. But since word | |
1519 | * reads are atomic, we either get new values or old values and we don't | |
1520 | * care which for the sums. We always take the siglock to protect reading | |
1521 | * the c* fields from p->signal from races with exit.c updating those | |
1522 | * fields when reaping, so a sample either gets all the additions of a | |
1523 | * given child after it's reaped, or none so this sample is before reaping. | |
2dd0ebcd | 1524 | * |
de047c1b RT |
1525 | * Locking: |
1526 | * We need to take the siglock for CHILDEREN, SELF and BOTH | |
1527 | * for the cases current multithreaded, non-current single threaded | |
1528 | * non-current multithreaded. Thread traversal is now safe with | |
1529 | * the siglock held. | |
1530 | * Strictly speaking, we donot need to take the siglock if we are current and | |
1531 | * single threaded, as no one else can take our signal_struct away, no one | |
1532 | * else can reap the children to update signal->c* counters, and no one else | |
1533 | * can race with the signal-> fields. If we do not take any lock, the | |
1534 | * signal-> fields could be read out of order while another thread was just | |
1535 | * exiting. So we should place a read memory barrier when we avoid the lock. | |
1536 | * On the writer side, write memory barrier is implied in __exit_signal | |
1537 | * as __exit_signal releases the siglock spinlock after updating the signal-> | |
1538 | * fields. But we don't do this yet to keep things simple. | |
2dd0ebcd | 1539 | * |
1da177e4 LT |
1540 | */ |
1541 | ||
1542 | static void k_getrusage(struct task_struct *p, int who, struct rusage *r) | |
1543 | { | |
1544 | struct task_struct *t; | |
1545 | unsigned long flags; | |
1546 | cputime_t utime, stime; | |
1547 | ||
1548 | memset((char *) r, 0, sizeof *r); | |
2dd0ebcd | 1549 | utime = stime = cputime_zero; |
1da177e4 | 1550 | |
de047c1b RT |
1551 | rcu_read_lock(); |
1552 | if (!lock_task_sighand(p, &flags)) { | |
1553 | rcu_read_unlock(); | |
1554 | return; | |
1555 | } | |
0f59cc4a | 1556 | |
1da177e4 | 1557 | switch (who) { |
0f59cc4a | 1558 | case RUSAGE_BOTH: |
1da177e4 | 1559 | case RUSAGE_CHILDREN: |
1da177e4 LT |
1560 | utime = p->signal->cutime; |
1561 | stime = p->signal->cstime; | |
1562 | r->ru_nvcsw = p->signal->cnvcsw; | |
1563 | r->ru_nivcsw = p->signal->cnivcsw; | |
1564 | r->ru_minflt = p->signal->cmin_flt; | |
1565 | r->ru_majflt = p->signal->cmaj_flt; | |
6eaeeaba ED |
1566 | r->ru_inblock = p->signal->cinblock; |
1567 | r->ru_oublock = p->signal->coublock; | |
0f59cc4a ON |
1568 | |
1569 | if (who == RUSAGE_CHILDREN) | |
1570 | break; | |
1571 | ||
1da177e4 | 1572 | case RUSAGE_SELF: |
1da177e4 LT |
1573 | utime = cputime_add(utime, p->signal->utime); |
1574 | stime = cputime_add(stime, p->signal->stime); | |
1575 | r->ru_nvcsw += p->signal->nvcsw; | |
1576 | r->ru_nivcsw += p->signal->nivcsw; | |
1577 | r->ru_minflt += p->signal->min_flt; | |
1578 | r->ru_majflt += p->signal->maj_flt; | |
6eaeeaba ED |
1579 | r->ru_inblock += p->signal->inblock; |
1580 | r->ru_oublock += p->signal->oublock; | |
1da177e4 LT |
1581 | t = p; |
1582 | do { | |
1583 | utime = cputime_add(utime, t->utime); | |
1584 | stime = cputime_add(stime, t->stime); | |
1585 | r->ru_nvcsw += t->nvcsw; | |
1586 | r->ru_nivcsw += t->nivcsw; | |
1587 | r->ru_minflt += t->min_flt; | |
1588 | r->ru_majflt += t->maj_flt; | |
6eaeeaba ED |
1589 | r->ru_inblock += task_io_get_inblock(t); |
1590 | r->ru_oublock += task_io_get_oublock(t); | |
1da177e4 LT |
1591 | t = next_thread(t); |
1592 | } while (t != p); | |
1da177e4 | 1593 | break; |
0f59cc4a | 1594 | |
1da177e4 LT |
1595 | default: |
1596 | BUG(); | |
1597 | } | |
0f59cc4a | 1598 | |
de047c1b RT |
1599 | unlock_task_sighand(p, &flags); |
1600 | rcu_read_unlock(); | |
1601 | ||
0f59cc4a ON |
1602 | cputime_to_timeval(utime, &r->ru_utime); |
1603 | cputime_to_timeval(stime, &r->ru_stime); | |
1da177e4 LT |
1604 | } |
1605 | ||
1606 | int getrusage(struct task_struct *p, int who, struct rusage __user *ru) | |
1607 | { | |
1608 | struct rusage r; | |
1da177e4 | 1609 | k_getrusage(p, who, &r); |
1da177e4 LT |
1610 | return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
1611 | } | |
1612 | ||
1613 | asmlinkage long sys_getrusage(int who, struct rusage __user *ru) | |
1614 | { | |
1615 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN) | |
1616 | return -EINVAL; | |
1617 | return getrusage(current, who, ru); | |
1618 | } | |
1619 | ||
1620 | asmlinkage long sys_umask(int mask) | |
1621 | { | |
1622 | mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); | |
1623 | return mask; | |
1624 | } | |
3b7391de | 1625 | |
1da177e4 LT |
1626 | asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3, |
1627 | unsigned long arg4, unsigned long arg5) | |
1628 | { | |
1629 | long error; | |
1da177e4 LT |
1630 | |
1631 | error = security_task_prctl(option, arg2, arg3, arg4, arg5); | |
1632 | if (error) | |
1633 | return error; | |
1634 | ||
1635 | switch (option) { | |
1636 | case PR_SET_PDEATHSIG: | |
0730ded5 | 1637 | if (!valid_signal(arg2)) { |
1da177e4 LT |
1638 | error = -EINVAL; |
1639 | break; | |
1640 | } | |
0730ded5 | 1641 | current->pdeath_signal = arg2; |
1da177e4 LT |
1642 | break; |
1643 | case PR_GET_PDEATHSIG: | |
1644 | error = put_user(current->pdeath_signal, (int __user *)arg2); | |
1645 | break; | |
1646 | case PR_GET_DUMPABLE: | |
6c5d5238 | 1647 | error = get_dumpable(current->mm); |
1da177e4 LT |
1648 | break; |
1649 | case PR_SET_DUMPABLE: | |
abf75a50 | 1650 | if (arg2 < 0 || arg2 > 1) { |
1da177e4 LT |
1651 | error = -EINVAL; |
1652 | break; | |
1653 | } | |
6c5d5238 | 1654 | set_dumpable(current->mm, arg2); |
1da177e4 LT |
1655 | break; |
1656 | ||
1657 | case PR_SET_UNALIGN: | |
1658 | error = SET_UNALIGN_CTL(current, arg2); | |
1659 | break; | |
1660 | case PR_GET_UNALIGN: | |
1661 | error = GET_UNALIGN_CTL(current, arg2); | |
1662 | break; | |
1663 | case PR_SET_FPEMU: | |
1664 | error = SET_FPEMU_CTL(current, arg2); | |
1665 | break; | |
1666 | case PR_GET_FPEMU: | |
1667 | error = GET_FPEMU_CTL(current, arg2); | |
1668 | break; | |
1669 | case PR_SET_FPEXC: | |
1670 | error = SET_FPEXC_CTL(current, arg2); | |
1671 | break; | |
1672 | case PR_GET_FPEXC: | |
1673 | error = GET_FPEXC_CTL(current, arg2); | |
1674 | break; | |
1675 | case PR_GET_TIMING: | |
1676 | error = PR_TIMING_STATISTICAL; | |
1677 | break; | |
1678 | case PR_SET_TIMING: | |
1679 | if (arg2 == PR_TIMING_STATISTICAL) | |
1680 | error = 0; | |
1681 | else | |
1682 | error = -EINVAL; | |
1683 | break; | |
1684 | ||
1685 | case PR_GET_KEEPCAPS: | |
1686 | if (current->keep_capabilities) | |
1687 | error = 1; | |
1688 | break; | |
1689 | case PR_SET_KEEPCAPS: | |
1690 | if (arg2 != 0 && arg2 != 1) { | |
1691 | error = -EINVAL; | |
1692 | break; | |
1693 | } | |
1694 | current->keep_capabilities = arg2; | |
1695 | break; | |
1696 | case PR_SET_NAME: { | |
1697 | struct task_struct *me = current; | |
1698 | unsigned char ncomm[sizeof(me->comm)]; | |
1699 | ||
1700 | ncomm[sizeof(me->comm)-1] = 0; | |
1701 | if (strncpy_from_user(ncomm, (char __user *)arg2, | |
1702 | sizeof(me->comm)-1) < 0) | |
1703 | return -EFAULT; | |
1704 | set_task_comm(me, ncomm); | |
1705 | return 0; | |
1706 | } | |
1707 | case PR_GET_NAME: { | |
1708 | struct task_struct *me = current; | |
1709 | unsigned char tcomm[sizeof(me->comm)]; | |
1710 | ||
1711 | get_task_comm(tcomm, me); | |
1712 | if (copy_to_user((char __user *)arg2, tcomm, sizeof(tcomm))) | |
1713 | return -EFAULT; | |
1714 | return 0; | |
1715 | } | |
651d765d AB |
1716 | case PR_GET_ENDIAN: |
1717 | error = GET_ENDIAN(current, arg2); | |
1718 | break; | |
1719 | case PR_SET_ENDIAN: | |
1720 | error = SET_ENDIAN(current, arg2); | |
1721 | break; | |
1722 | ||
1d9d02fe AA |
1723 | case PR_GET_SECCOMP: |
1724 | error = prctl_get_seccomp(); | |
1725 | break; | |
1726 | case PR_SET_SECCOMP: | |
1727 | error = prctl_set_seccomp(arg2); | |
1728 | break; | |
1729 | ||
3b7391de SH |
1730 | case PR_CAPBSET_READ: |
1731 | if (!cap_valid(arg2)) | |
1732 | return -EINVAL; | |
1733 | return !!cap_raised(current->cap_bset, arg2); | |
1734 | case PR_CAPBSET_DROP: | |
1735 | #ifdef CONFIG_SECURITY_FILE_CAPABILITIES | |
1736 | return cap_prctl_drop(arg2); | |
1737 | #else | |
1738 | return -EINVAL; | |
1739 | #endif | |
1740 | ||
1da177e4 LT |
1741 | default: |
1742 | error = -EINVAL; | |
1743 | break; | |
1744 | } | |
1745 | return error; | |
1746 | } | |
3cfc348b AK |
1747 | |
1748 | asmlinkage long sys_getcpu(unsigned __user *cpup, unsigned __user *nodep, | |
4307d1e5 | 1749 | struct getcpu_cache __user *unused) |
3cfc348b AK |
1750 | { |
1751 | int err = 0; | |
1752 | int cpu = raw_smp_processor_id(); | |
1753 | if (cpup) | |
1754 | err |= put_user(cpu, cpup); | |
1755 | if (nodep) | |
1756 | err |= put_user(cpu_to_node(cpu), nodep); | |
3cfc348b AK |
1757 | return err ? -EFAULT : 0; |
1758 | } | |
10a0a8d4 JF |
1759 | |
1760 | char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff"; | |
1761 | ||
1762 | static void argv_cleanup(char **argv, char **envp) | |
1763 | { | |
1764 | argv_free(argv); | |
1765 | } | |
1766 | ||
1767 | /** | |
1768 | * orderly_poweroff - Trigger an orderly system poweroff | |
1769 | * @force: force poweroff if command execution fails | |
1770 | * | |
1771 | * This may be called from any context to trigger a system shutdown. | |
1772 | * If the orderly shutdown fails, it will force an immediate shutdown. | |
1773 | */ | |
1774 | int orderly_poweroff(bool force) | |
1775 | { | |
1776 | int argc; | |
1777 | char **argv = argv_split(GFP_ATOMIC, poweroff_cmd, &argc); | |
1778 | static char *envp[] = { | |
1779 | "HOME=/", | |
1780 | "PATH=/sbin:/bin:/usr/sbin:/usr/bin", | |
1781 | NULL | |
1782 | }; | |
1783 | int ret = -ENOMEM; | |
1784 | struct subprocess_info *info; | |
1785 | ||
1786 | if (argv == NULL) { | |
1787 | printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n", | |
1788 | __func__, poweroff_cmd); | |
1789 | goto out; | |
1790 | } | |
1791 | ||
1792 | info = call_usermodehelper_setup(argv[0], argv, envp); | |
1793 | if (info == NULL) { | |
1794 | argv_free(argv); | |
1795 | goto out; | |
1796 | } | |
1797 | ||
1798 | call_usermodehelper_setcleanup(info, argv_cleanup); | |
1799 | ||
86313c48 | 1800 | ret = call_usermodehelper_exec(info, UMH_NO_WAIT); |
10a0a8d4 JF |
1801 | |
1802 | out: | |
1803 | if (ret && force) { | |
1804 | printk(KERN_WARNING "Failed to start orderly shutdown: " | |
1805 | "forcing the issue\n"); | |
1806 | ||
1807 | /* I guess this should try to kick off some daemon to | |
1808 | sync and poweroff asap. Or not even bother syncing | |
1809 | if we're doing an emergency shutdown? */ | |
1810 | emergency_sync(); | |
1811 | kernel_power_off(); | |
1812 | } | |
1813 | ||
1814 | return ret; | |
1815 | } | |
1816 | EXPORT_SYMBOL_GPL(orderly_poweroff); |