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 | |
8fb402bc EB |
70 | #ifndef GET_TSC_CTL |
71 | # define GET_TSC_CTL(a) (-EINVAL) | |
72 | #endif | |
73 | #ifndef SET_TSC_CTL | |
74 | # define SET_TSC_CTL(a) (-EINVAL) | |
75 | #endif | |
1da177e4 LT |
76 | |
77 | /* | |
78 | * this is where the system-wide overflow UID and GID are defined, for | |
79 | * architectures that now have 32-bit UID/GID but didn't in the past | |
80 | */ | |
81 | ||
82 | int overflowuid = DEFAULT_OVERFLOWUID; | |
83 | int overflowgid = DEFAULT_OVERFLOWGID; | |
84 | ||
85 | #ifdef CONFIG_UID16 | |
86 | EXPORT_SYMBOL(overflowuid); | |
87 | EXPORT_SYMBOL(overflowgid); | |
88 | #endif | |
89 | ||
90 | /* | |
91 | * the same as above, but for filesystems which can only store a 16-bit | |
92 | * UID and GID. as such, this is needed on all architectures | |
93 | */ | |
94 | ||
95 | int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; | |
96 | int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; | |
97 | ||
98 | EXPORT_SYMBOL(fs_overflowuid); | |
99 | EXPORT_SYMBOL(fs_overflowgid); | |
100 | ||
101 | /* | |
102 | * this indicates whether you can reboot with ctrl-alt-del: the default is yes | |
103 | */ | |
104 | ||
105 | int C_A_D = 1; | |
9ec52099 CLG |
106 | struct pid *cad_pid; |
107 | EXPORT_SYMBOL(cad_pid); | |
1da177e4 | 108 | |
bd804eba RW |
109 | /* |
110 | * If set, this is used for preparing the system to power off. | |
111 | */ | |
112 | ||
113 | void (*pm_power_off_prepare)(void); | |
bd804eba | 114 | |
c69e8d9c DH |
115 | /* |
116 | * set the priority of a task | |
117 | * - the caller must hold the RCU read lock | |
118 | */ | |
1da177e4 LT |
119 | static int set_one_prio(struct task_struct *p, int niceval, int error) |
120 | { | |
c69e8d9c | 121 | const struct cred *cred = current_cred(), *pcred = __task_cred(p); |
1da177e4 LT |
122 | int no_nice; |
123 | ||
c69e8d9c DH |
124 | if (pcred->uid != cred->euid && |
125 | pcred->euid != cred->euid && !capable(CAP_SYS_NICE)) { | |
1da177e4 LT |
126 | error = -EPERM; |
127 | goto out; | |
128 | } | |
e43379f1 | 129 | if (niceval < task_nice(p) && !can_nice(p, niceval)) { |
1da177e4 LT |
130 | error = -EACCES; |
131 | goto out; | |
132 | } | |
133 | no_nice = security_task_setnice(p, niceval); | |
134 | if (no_nice) { | |
135 | error = no_nice; | |
136 | goto out; | |
137 | } | |
138 | if (error == -ESRCH) | |
139 | error = 0; | |
140 | set_user_nice(p, niceval); | |
141 | out: | |
142 | return error; | |
143 | } | |
144 | ||
145 | asmlinkage long sys_setpriority(int which, int who, int niceval) | |
146 | { | |
147 | struct task_struct *g, *p; | |
148 | struct user_struct *user; | |
86a264ab | 149 | const struct cred *cred = current_cred(); |
1da177e4 | 150 | int error = -EINVAL; |
41487c65 | 151 | struct pid *pgrp; |
1da177e4 | 152 | |
3e88c553 | 153 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
154 | goto out; |
155 | ||
156 | /* normalize: avoid signed division (rounding problems) */ | |
157 | error = -ESRCH; | |
158 | if (niceval < -20) | |
159 | niceval = -20; | |
160 | if (niceval > 19) | |
161 | niceval = 19; | |
162 | ||
163 | read_lock(&tasklist_lock); | |
164 | switch (which) { | |
165 | case PRIO_PROCESS: | |
41487c65 | 166 | if (who) |
228ebcbe | 167 | p = find_task_by_vpid(who); |
41487c65 EB |
168 | else |
169 | p = current; | |
1da177e4 LT |
170 | if (p) |
171 | error = set_one_prio(p, niceval, error); | |
172 | break; | |
173 | case PRIO_PGRP: | |
41487c65 | 174 | if (who) |
b488893a | 175 | pgrp = find_vpid(who); |
41487c65 EB |
176 | else |
177 | pgrp = task_pgrp(current); | |
2d70b68d | 178 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 | 179 | error = set_one_prio(p, niceval, error); |
2d70b68d | 180 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
181 | break; |
182 | case PRIO_USER: | |
d84f4f99 | 183 | user = (struct user_struct *) cred->user; |
1da177e4 | 184 | if (!who) |
86a264ab DH |
185 | who = cred->uid; |
186 | else if ((who != cred->uid) && | |
187 | !(user = find_user(who))) | |
188 | goto out_unlock; /* No processes for this user */ | |
1da177e4 LT |
189 | |
190 | do_each_thread(g, p) | |
86a264ab | 191 | if (__task_cred(p)->uid == who) |
1da177e4 LT |
192 | error = set_one_prio(p, niceval, error); |
193 | while_each_thread(g, p); | |
86a264ab | 194 | if (who != cred->uid) |
1da177e4 LT |
195 | free_uid(user); /* For find_user() */ |
196 | break; | |
197 | } | |
198 | out_unlock: | |
199 | read_unlock(&tasklist_lock); | |
200 | out: | |
201 | return error; | |
202 | } | |
203 | ||
204 | /* | |
205 | * Ugh. To avoid negative return values, "getpriority()" will | |
206 | * not return the normal nice-value, but a negated value that | |
207 | * has been offset by 20 (ie it returns 40..1 instead of -20..19) | |
208 | * to stay compatible. | |
209 | */ | |
210 | asmlinkage long sys_getpriority(int which, int who) | |
211 | { | |
212 | struct task_struct *g, *p; | |
213 | struct user_struct *user; | |
86a264ab | 214 | const struct cred *cred = current_cred(); |
1da177e4 | 215 | long niceval, retval = -ESRCH; |
41487c65 | 216 | struct pid *pgrp; |
1da177e4 | 217 | |
3e88c553 | 218 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
219 | return -EINVAL; |
220 | ||
221 | read_lock(&tasklist_lock); | |
222 | switch (which) { | |
223 | case PRIO_PROCESS: | |
41487c65 | 224 | if (who) |
228ebcbe | 225 | p = find_task_by_vpid(who); |
41487c65 EB |
226 | else |
227 | p = current; | |
1da177e4 LT |
228 | if (p) { |
229 | niceval = 20 - task_nice(p); | |
230 | if (niceval > retval) | |
231 | retval = niceval; | |
232 | } | |
233 | break; | |
234 | case PRIO_PGRP: | |
41487c65 | 235 | if (who) |
b488893a | 236 | pgrp = find_vpid(who); |
41487c65 EB |
237 | else |
238 | pgrp = task_pgrp(current); | |
2d70b68d | 239 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 LT |
240 | niceval = 20 - task_nice(p); |
241 | if (niceval > retval) | |
242 | retval = niceval; | |
2d70b68d | 243 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
244 | break; |
245 | case PRIO_USER: | |
86a264ab | 246 | user = (struct user_struct *) cred->user; |
1da177e4 | 247 | if (!who) |
86a264ab DH |
248 | who = cred->uid; |
249 | else if ((who != cred->uid) && | |
250 | !(user = find_user(who))) | |
251 | goto out_unlock; /* No processes for this user */ | |
1da177e4 LT |
252 | |
253 | do_each_thread(g, p) | |
86a264ab | 254 | if (__task_cred(p)->uid == who) { |
1da177e4 LT |
255 | niceval = 20 - task_nice(p); |
256 | if (niceval > retval) | |
257 | retval = niceval; | |
258 | } | |
259 | while_each_thread(g, p); | |
86a264ab | 260 | if (who != cred->uid) |
1da177e4 LT |
261 | free_uid(user); /* for find_user() */ |
262 | break; | |
263 | } | |
264 | out_unlock: | |
265 | read_unlock(&tasklist_lock); | |
266 | ||
267 | return retval; | |
268 | } | |
269 | ||
e4c94330 EB |
270 | /** |
271 | * emergency_restart - reboot the system | |
272 | * | |
273 | * Without shutting down any hardware or taking any locks | |
274 | * reboot the system. This is called when we know we are in | |
275 | * trouble so this is our best effort to reboot. This is | |
276 | * safe to call in interrupt context. | |
277 | */ | |
7c903473 EB |
278 | void emergency_restart(void) |
279 | { | |
280 | machine_emergency_restart(); | |
281 | } | |
282 | EXPORT_SYMBOL_GPL(emergency_restart); | |
283 | ||
ca195b7f | 284 | void kernel_restart_prepare(char *cmd) |
4a00ea1e | 285 | { |
e041c683 | 286 | blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd); |
4a00ea1e | 287 | system_state = SYSTEM_RESTART; |
4a00ea1e | 288 | device_shutdown(); |
58b3b71d | 289 | sysdev_shutdown(); |
e4c94330 | 290 | } |
1e5d5331 RD |
291 | |
292 | /** | |
293 | * kernel_restart - reboot the system | |
294 | * @cmd: pointer to buffer containing command to execute for restart | |
b8887e6e | 295 | * or %NULL |
1e5d5331 RD |
296 | * |
297 | * Shutdown everything and perform a clean reboot. | |
298 | * This is not safe to call in interrupt context. | |
299 | */ | |
e4c94330 EB |
300 | void kernel_restart(char *cmd) |
301 | { | |
302 | kernel_restart_prepare(cmd); | |
756184b7 | 303 | if (!cmd) |
4a00ea1e | 304 | printk(KERN_EMERG "Restarting system.\n"); |
756184b7 | 305 | else |
4a00ea1e | 306 | printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd); |
4a00ea1e EB |
307 | machine_restart(cmd); |
308 | } | |
309 | EXPORT_SYMBOL_GPL(kernel_restart); | |
310 | ||
4ef7229f | 311 | static void kernel_shutdown_prepare(enum system_states state) |
729b4d4c | 312 | { |
e041c683 | 313 | blocking_notifier_call_chain(&reboot_notifier_list, |
729b4d4c AS |
314 | (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL); |
315 | system_state = state; | |
316 | device_shutdown(); | |
317 | } | |
e4c94330 EB |
318 | /** |
319 | * kernel_halt - halt the system | |
320 | * | |
321 | * Shutdown everything and perform a clean system halt. | |
322 | */ | |
e4c94330 EB |
323 | void kernel_halt(void) |
324 | { | |
729b4d4c | 325 | kernel_shutdown_prepare(SYSTEM_HALT); |
58b3b71d | 326 | sysdev_shutdown(); |
4a00ea1e EB |
327 | printk(KERN_EMERG "System halted.\n"); |
328 | machine_halt(); | |
329 | } | |
729b4d4c | 330 | |
4a00ea1e EB |
331 | EXPORT_SYMBOL_GPL(kernel_halt); |
332 | ||
e4c94330 EB |
333 | /** |
334 | * kernel_power_off - power_off the system | |
335 | * | |
336 | * Shutdown everything and perform a clean system power_off. | |
337 | */ | |
e4c94330 EB |
338 | void kernel_power_off(void) |
339 | { | |
729b4d4c | 340 | kernel_shutdown_prepare(SYSTEM_POWER_OFF); |
bd804eba RW |
341 | if (pm_power_off_prepare) |
342 | pm_power_off_prepare(); | |
4047727e | 343 | disable_nonboot_cpus(); |
58b3b71d | 344 | sysdev_shutdown(); |
4a00ea1e EB |
345 | printk(KERN_EMERG "Power down.\n"); |
346 | machine_power_off(); | |
347 | } | |
348 | EXPORT_SYMBOL_GPL(kernel_power_off); | |
1da177e4 LT |
349 | /* |
350 | * Reboot system call: for obvious reasons only root may call it, | |
351 | * and even root needs to set up some magic numbers in the registers | |
352 | * so that some mistake won't make this reboot the whole machine. | |
353 | * You can also set the meaning of the ctrl-alt-del-key here. | |
354 | * | |
355 | * reboot doesn't sync: do that yourself before calling this. | |
356 | */ | |
357 | asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user * arg) | |
358 | { | |
359 | char buffer[256]; | |
360 | ||
361 | /* We only trust the superuser with rebooting the system. */ | |
362 | if (!capable(CAP_SYS_BOOT)) | |
363 | return -EPERM; | |
364 | ||
365 | /* For safety, we require "magic" arguments. */ | |
366 | if (magic1 != LINUX_REBOOT_MAGIC1 || | |
367 | (magic2 != LINUX_REBOOT_MAGIC2 && | |
368 | magic2 != LINUX_REBOOT_MAGIC2A && | |
369 | magic2 != LINUX_REBOOT_MAGIC2B && | |
370 | magic2 != LINUX_REBOOT_MAGIC2C)) | |
371 | return -EINVAL; | |
372 | ||
5e38291d EB |
373 | /* Instead of trying to make the power_off code look like |
374 | * halt when pm_power_off is not set do it the easy way. | |
375 | */ | |
376 | if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off) | |
377 | cmd = LINUX_REBOOT_CMD_HALT; | |
378 | ||
1da177e4 LT |
379 | lock_kernel(); |
380 | switch (cmd) { | |
381 | case LINUX_REBOOT_CMD_RESTART: | |
4a00ea1e | 382 | kernel_restart(NULL); |
1da177e4 LT |
383 | break; |
384 | ||
385 | case LINUX_REBOOT_CMD_CAD_ON: | |
386 | C_A_D = 1; | |
387 | break; | |
388 | ||
389 | case LINUX_REBOOT_CMD_CAD_OFF: | |
390 | C_A_D = 0; | |
391 | break; | |
392 | ||
393 | case LINUX_REBOOT_CMD_HALT: | |
4a00ea1e | 394 | kernel_halt(); |
1da177e4 LT |
395 | unlock_kernel(); |
396 | do_exit(0); | |
397 | break; | |
398 | ||
399 | case LINUX_REBOOT_CMD_POWER_OFF: | |
4a00ea1e | 400 | kernel_power_off(); |
1da177e4 LT |
401 | unlock_kernel(); |
402 | do_exit(0); | |
403 | break; | |
404 | ||
405 | case LINUX_REBOOT_CMD_RESTART2: | |
406 | if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) { | |
407 | unlock_kernel(); | |
408 | return -EFAULT; | |
409 | } | |
410 | buffer[sizeof(buffer) - 1] = '\0'; | |
411 | ||
4a00ea1e | 412 | kernel_restart(buffer); |
1da177e4 LT |
413 | break; |
414 | ||
3ab83521 | 415 | #ifdef CONFIG_KEXEC |
dc009d92 | 416 | case LINUX_REBOOT_CMD_KEXEC: |
3ab83521 HY |
417 | { |
418 | int ret; | |
419 | ret = kernel_kexec(); | |
420 | unlock_kernel(); | |
421 | return ret; | |
422 | } | |
423 | #endif | |
4a00ea1e | 424 | |
b0cb1a19 | 425 | #ifdef CONFIG_HIBERNATION |
1da177e4 LT |
426 | case LINUX_REBOOT_CMD_SW_SUSPEND: |
427 | { | |
a3d25c27 | 428 | int ret = hibernate(); |
1da177e4 LT |
429 | unlock_kernel(); |
430 | return ret; | |
431 | } | |
432 | #endif | |
433 | ||
434 | default: | |
435 | unlock_kernel(); | |
436 | return -EINVAL; | |
437 | } | |
438 | unlock_kernel(); | |
439 | return 0; | |
440 | } | |
441 | ||
65f27f38 | 442 | static void deferred_cad(struct work_struct *dummy) |
1da177e4 | 443 | { |
abcd9e51 | 444 | kernel_restart(NULL); |
1da177e4 LT |
445 | } |
446 | ||
447 | /* | |
448 | * This function gets called by ctrl-alt-del - ie the keyboard interrupt. | |
449 | * As it's called within an interrupt, it may NOT sync: the only choice | |
450 | * is whether to reboot at once, or just ignore the ctrl-alt-del. | |
451 | */ | |
452 | void ctrl_alt_del(void) | |
453 | { | |
65f27f38 | 454 | static DECLARE_WORK(cad_work, deferred_cad); |
1da177e4 LT |
455 | |
456 | if (C_A_D) | |
457 | schedule_work(&cad_work); | |
458 | else | |
9ec52099 | 459 | kill_cad_pid(SIGINT, 1); |
1da177e4 LT |
460 | } |
461 | ||
1da177e4 LT |
462 | /* |
463 | * Unprivileged users may change the real gid to the effective gid | |
464 | * or vice versa. (BSD-style) | |
465 | * | |
466 | * If you set the real gid at all, or set the effective gid to a value not | |
467 | * equal to the real gid, then the saved gid is set to the new effective gid. | |
468 | * | |
469 | * This makes it possible for a setgid program to completely drop its | |
470 | * privileges, which is often a useful assertion to make when you are doing | |
471 | * a security audit over a program. | |
472 | * | |
473 | * The general idea is that a program which uses just setregid() will be | |
474 | * 100% compatible with BSD. A program which uses just setgid() will be | |
475 | * 100% compatible with POSIX with saved IDs. | |
476 | * | |
477 | * SMP: There are not races, the GIDs are checked only by filesystem | |
478 | * operations (as far as semantic preservation is concerned). | |
479 | */ | |
480 | asmlinkage long sys_setregid(gid_t rgid, gid_t egid) | |
481 | { | |
d84f4f99 DH |
482 | const struct cred *old; |
483 | struct cred *new; | |
1da177e4 LT |
484 | int retval; |
485 | ||
d84f4f99 DH |
486 | new = prepare_creds(); |
487 | if (!new) | |
488 | return -ENOMEM; | |
489 | old = current_cred(); | |
490 | ||
1da177e4 LT |
491 | retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE); |
492 | if (retval) | |
d84f4f99 | 493 | goto error; |
1da177e4 | 494 | |
d84f4f99 | 495 | retval = -EPERM; |
1da177e4 | 496 | if (rgid != (gid_t) -1) { |
d84f4f99 DH |
497 | if (old->gid == rgid || |
498 | old->egid == rgid || | |
1da177e4 | 499 | capable(CAP_SETGID)) |
d84f4f99 | 500 | new->gid = rgid; |
1da177e4 | 501 | else |
d84f4f99 | 502 | goto error; |
1da177e4 LT |
503 | } |
504 | if (egid != (gid_t) -1) { | |
d84f4f99 DH |
505 | if (old->gid == egid || |
506 | old->egid == egid || | |
507 | old->sgid == egid || | |
1da177e4 | 508 | capable(CAP_SETGID)) |
d84f4f99 | 509 | new->egid = egid; |
756184b7 | 510 | else |
d84f4f99 | 511 | goto error; |
1da177e4 | 512 | } |
d84f4f99 | 513 | |
1da177e4 | 514 | if (rgid != (gid_t) -1 || |
d84f4f99 DH |
515 | (egid != (gid_t) -1 && egid != old->gid)) |
516 | new->sgid = new->egid; | |
517 | new->fsgid = new->egid; | |
518 | ||
519 | return commit_creds(new); | |
520 | ||
521 | error: | |
522 | abort_creds(new); | |
523 | return retval; | |
1da177e4 LT |
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 | { | |
d84f4f99 DH |
533 | const struct cred *old; |
534 | struct cred *new; | |
1da177e4 LT |
535 | int retval; |
536 | ||
d84f4f99 DH |
537 | new = prepare_creds(); |
538 | if (!new) | |
539 | return -ENOMEM; | |
540 | old = current_cred(); | |
541 | ||
1da177e4 LT |
542 | retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID); |
543 | if (retval) | |
d84f4f99 | 544 | goto error; |
1da177e4 | 545 | |
d84f4f99 DH |
546 | retval = -EPERM; |
547 | if (capable(CAP_SETGID)) | |
548 | new->gid = new->egid = new->sgid = new->fsgid = gid; | |
549 | else if (gid == old->gid || gid == old->sgid) | |
550 | new->egid = new->fsgid = gid; | |
1da177e4 | 551 | else |
d84f4f99 | 552 | goto error; |
1da177e4 | 553 | |
d84f4f99 DH |
554 | return commit_creds(new); |
555 | ||
556 | error: | |
557 | abort_creds(new); | |
558 | return retval; | |
1da177e4 LT |
559 | } |
560 | ||
d84f4f99 DH |
561 | /* |
562 | * change the user struct in a credentials set to match the new UID | |
563 | */ | |
564 | static int set_user(struct cred *new) | |
1da177e4 LT |
565 | { |
566 | struct user_struct *new_user; | |
567 | ||
18b6e041 | 568 | new_user = alloc_uid(current_user_ns(), new->uid); |
1da177e4 LT |
569 | if (!new_user) |
570 | return -EAGAIN; | |
571 | ||
572 | if (atomic_read(&new_user->processes) >= | |
573 | current->signal->rlim[RLIMIT_NPROC].rlim_cur && | |
18b6e041 | 574 | new_user != INIT_USER) { |
1da177e4 LT |
575 | free_uid(new_user); |
576 | return -EAGAIN; | |
577 | } | |
578 | ||
d84f4f99 DH |
579 | free_uid(new->user); |
580 | new->user = new_user; | |
1da177e4 LT |
581 | return 0; |
582 | } | |
583 | ||
584 | /* | |
585 | * Unprivileged users may change the real uid to the effective uid | |
586 | * or vice versa. (BSD-style) | |
587 | * | |
588 | * If you set the real uid at all, or set the effective uid to a value not | |
589 | * equal to the real uid, then the saved uid is set to the new effective uid. | |
590 | * | |
591 | * This makes it possible for a setuid program to completely drop its | |
592 | * privileges, which is often a useful assertion to make when you are doing | |
593 | * a security audit over a program. | |
594 | * | |
595 | * The general idea is that a program which uses just setreuid() will be | |
596 | * 100% compatible with BSD. A program which uses just setuid() will be | |
597 | * 100% compatible with POSIX with saved IDs. | |
598 | */ | |
599 | asmlinkage long sys_setreuid(uid_t ruid, uid_t euid) | |
600 | { | |
d84f4f99 DH |
601 | const struct cred *old; |
602 | struct cred *new; | |
1da177e4 LT |
603 | int retval; |
604 | ||
d84f4f99 DH |
605 | new = prepare_creds(); |
606 | if (!new) | |
607 | return -ENOMEM; | |
608 | old = current_cred(); | |
609 | ||
1da177e4 LT |
610 | retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE); |
611 | if (retval) | |
d84f4f99 | 612 | goto error; |
1da177e4 | 613 | |
d84f4f99 | 614 | retval = -EPERM; |
1da177e4 | 615 | if (ruid != (uid_t) -1) { |
d84f4f99 DH |
616 | new->uid = ruid; |
617 | if (old->uid != ruid && | |
618 | old->euid != ruid && | |
1da177e4 | 619 | !capable(CAP_SETUID)) |
d84f4f99 | 620 | goto error; |
1da177e4 LT |
621 | } |
622 | ||
623 | if (euid != (uid_t) -1) { | |
d84f4f99 DH |
624 | new->euid = euid; |
625 | if (old->uid != euid && | |
626 | old->euid != euid && | |
627 | old->suid != euid && | |
1da177e4 | 628 | !capable(CAP_SETUID)) |
d84f4f99 | 629 | goto error; |
1da177e4 LT |
630 | } |
631 | ||
d84f4f99 DH |
632 | retval = -EAGAIN; |
633 | if (new->uid != old->uid && set_user(new) < 0) | |
634 | goto error; | |
1da177e4 | 635 | |
1da177e4 | 636 | if (ruid != (uid_t) -1 || |
d84f4f99 DH |
637 | (euid != (uid_t) -1 && euid != old->uid)) |
638 | new->suid = new->euid; | |
639 | new->fsuid = new->euid; | |
1da177e4 | 640 | |
d84f4f99 DH |
641 | retval = security_task_fix_setuid(new, old, LSM_SETID_RE); |
642 | if (retval < 0) | |
643 | goto error; | |
1da177e4 | 644 | |
d84f4f99 | 645 | return commit_creds(new); |
1da177e4 | 646 | |
d84f4f99 DH |
647 | error: |
648 | abort_creds(new); | |
649 | return retval; | |
650 | } | |
1da177e4 LT |
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 | { | |
d84f4f99 DH |
665 | const struct cred *old; |
666 | struct cred *new; | |
1da177e4 LT |
667 | int retval; |
668 | ||
d84f4f99 DH |
669 | new = prepare_creds(); |
670 | if (!new) | |
671 | return -ENOMEM; | |
672 | old = current_cred(); | |
673 | ||
1da177e4 LT |
674 | retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID); |
675 | if (retval) | |
d84f4f99 | 676 | goto error; |
1da177e4 | 677 | |
d84f4f99 | 678 | retval = -EPERM; |
1da177e4 | 679 | if (capable(CAP_SETUID)) { |
d84f4f99 DH |
680 | new->suid = new->uid = uid; |
681 | if (uid != old->uid && set_user(new) < 0) { | |
682 | retval = -EAGAIN; | |
683 | goto error; | |
684 | } | |
685 | } else if (uid != old->uid && uid != new->suid) { | |
686 | goto error; | |
1da177e4 | 687 | } |
1da177e4 | 688 | |
d84f4f99 DH |
689 | new->fsuid = new->euid = uid; |
690 | ||
691 | retval = security_task_fix_setuid(new, old, LSM_SETID_ID); | |
692 | if (retval < 0) | |
693 | goto error; | |
694 | ||
695 | return commit_creds(new); | |
1da177e4 | 696 | |
d84f4f99 DH |
697 | error: |
698 | abort_creds(new); | |
699 | return retval; | |
1da177e4 LT |
700 | } |
701 | ||
702 | ||
703 | /* | |
704 | * This function implements a generic ability to update ruid, euid, | |
705 | * and suid. This allows you to implement the 4.4 compatible seteuid(). | |
706 | */ | |
707 | asmlinkage long sys_setresuid(uid_t ruid, uid_t euid, uid_t suid) | |
708 | { | |
d84f4f99 DH |
709 | const struct cred *old; |
710 | struct cred *new; | |
1da177e4 LT |
711 | int retval; |
712 | ||
d84f4f99 DH |
713 | new = prepare_creds(); |
714 | if (!new) | |
715 | return -ENOMEM; | |
716 | ||
1da177e4 LT |
717 | retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES); |
718 | if (retval) | |
d84f4f99 DH |
719 | goto error; |
720 | old = current_cred(); | |
1da177e4 | 721 | |
d84f4f99 | 722 | retval = -EPERM; |
1da177e4 | 723 | if (!capable(CAP_SETUID)) { |
d84f4f99 DH |
724 | if (ruid != (uid_t) -1 && ruid != old->uid && |
725 | ruid != old->euid && ruid != old->suid) | |
726 | goto error; | |
727 | if (euid != (uid_t) -1 && euid != old->uid && | |
728 | euid != old->euid && euid != old->suid) | |
729 | goto error; | |
730 | if (suid != (uid_t) -1 && suid != old->uid && | |
731 | suid != old->euid && suid != old->suid) | |
732 | goto error; | |
1da177e4 | 733 | } |
d84f4f99 DH |
734 | |
735 | retval = -EAGAIN; | |
1da177e4 | 736 | if (ruid != (uid_t) -1) { |
d84f4f99 DH |
737 | new->uid = ruid; |
738 | if (ruid != old->uid && set_user(new) < 0) | |
739 | goto error; | |
1da177e4 | 740 | } |
d84f4f99 DH |
741 | if (euid != (uid_t) -1) |
742 | new->euid = euid; | |
1da177e4 | 743 | if (suid != (uid_t) -1) |
d84f4f99 DH |
744 | new->suid = suid; |
745 | new->fsuid = new->euid; | |
1da177e4 | 746 | |
d84f4f99 DH |
747 | retval = security_task_fix_setuid(new, old, LSM_SETID_RES); |
748 | if (retval < 0) | |
749 | goto error; | |
1da177e4 | 750 | |
d84f4f99 DH |
751 | return commit_creds(new); |
752 | ||
753 | error: | |
754 | abort_creds(new); | |
755 | return retval; | |
1da177e4 LT |
756 | } |
757 | ||
758 | asmlinkage long sys_getresuid(uid_t __user *ruid, uid_t __user *euid, uid_t __user *suid) | |
759 | { | |
86a264ab | 760 | const struct cred *cred = current_cred(); |
1da177e4 LT |
761 | int retval; |
762 | ||
86a264ab DH |
763 | if (!(retval = put_user(cred->uid, ruid)) && |
764 | !(retval = put_user(cred->euid, euid))) | |
b6dff3ec | 765 | retval = put_user(cred->suid, suid); |
1da177e4 LT |
766 | |
767 | return retval; | |
768 | } | |
769 | ||
770 | /* | |
771 | * Same as above, but for rgid, egid, sgid. | |
772 | */ | |
773 | asmlinkage long sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid) | |
774 | { | |
d84f4f99 DH |
775 | const struct cred *old; |
776 | struct cred *new; | |
1da177e4 LT |
777 | int retval; |
778 | ||
d84f4f99 DH |
779 | new = prepare_creds(); |
780 | if (!new) | |
781 | return -ENOMEM; | |
782 | old = current_cred(); | |
783 | ||
1da177e4 LT |
784 | retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES); |
785 | if (retval) | |
d84f4f99 | 786 | goto error; |
1da177e4 | 787 | |
d84f4f99 | 788 | retval = -EPERM; |
1da177e4 | 789 | if (!capable(CAP_SETGID)) { |
d84f4f99 DH |
790 | if (rgid != (gid_t) -1 && rgid != old->gid && |
791 | rgid != old->egid && rgid != old->sgid) | |
792 | goto error; | |
793 | if (egid != (gid_t) -1 && egid != old->gid && | |
794 | egid != old->egid && egid != old->sgid) | |
795 | goto error; | |
796 | if (sgid != (gid_t) -1 && sgid != old->gid && | |
797 | sgid != old->egid && sgid != old->sgid) | |
798 | goto error; | |
1da177e4 | 799 | } |
d84f4f99 | 800 | |
1da177e4 | 801 | if (rgid != (gid_t) -1) |
d84f4f99 DH |
802 | new->gid = rgid; |
803 | if (egid != (gid_t) -1) | |
804 | new->egid = egid; | |
1da177e4 | 805 | if (sgid != (gid_t) -1) |
d84f4f99 DH |
806 | new->sgid = sgid; |
807 | new->fsgid = new->egid; | |
1da177e4 | 808 | |
d84f4f99 DH |
809 | return commit_creds(new); |
810 | ||
811 | error: | |
812 | abort_creds(new); | |
813 | return retval; | |
1da177e4 LT |
814 | } |
815 | ||
816 | asmlinkage long sys_getresgid(gid_t __user *rgid, gid_t __user *egid, gid_t __user *sgid) | |
817 | { | |
86a264ab | 818 | const struct cred *cred = current_cred(); |
1da177e4 LT |
819 | int retval; |
820 | ||
86a264ab DH |
821 | if (!(retval = put_user(cred->gid, rgid)) && |
822 | !(retval = put_user(cred->egid, egid))) | |
b6dff3ec | 823 | retval = put_user(cred->sgid, sgid); |
1da177e4 LT |
824 | |
825 | return retval; | |
826 | } | |
827 | ||
828 | ||
829 | /* | |
830 | * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This | |
831 | * is used for "access()" and for the NFS daemon (letting nfsd stay at | |
832 | * whatever uid it wants to). It normally shadows "euid", except when | |
833 | * explicitly set by setfsuid() or for access.. | |
834 | */ | |
835 | asmlinkage long sys_setfsuid(uid_t uid) | |
836 | { | |
d84f4f99 DH |
837 | const struct cred *old; |
838 | struct cred *new; | |
839 | uid_t old_fsuid; | |
840 | ||
841 | new = prepare_creds(); | |
842 | if (!new) | |
843 | return current_fsuid(); | |
844 | old = current_cred(); | |
845 | old_fsuid = old->fsuid; | |
1da177e4 | 846 | |
d84f4f99 DH |
847 | if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS) < 0) |
848 | goto error; | |
1da177e4 | 849 | |
d84f4f99 DH |
850 | if (uid == old->uid || uid == old->euid || |
851 | uid == old->suid || uid == old->fsuid || | |
756184b7 CP |
852 | capable(CAP_SETUID)) { |
853 | if (uid != old_fsuid) { | |
d84f4f99 DH |
854 | new->fsuid = uid; |
855 | if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) | |
856 | goto change_okay; | |
1da177e4 | 857 | } |
1da177e4 LT |
858 | } |
859 | ||
d84f4f99 DH |
860 | error: |
861 | abort_creds(new); | |
862 | return old_fsuid; | |
1da177e4 | 863 | |
d84f4f99 DH |
864 | change_okay: |
865 | commit_creds(new); | |
1da177e4 LT |
866 | return old_fsuid; |
867 | } | |
868 | ||
869 | /* | |
f42df9e6 | 870 | * Samma på svenska.. |
1da177e4 LT |
871 | */ |
872 | asmlinkage long sys_setfsgid(gid_t gid) | |
873 | { | |
d84f4f99 DH |
874 | const struct cred *old; |
875 | struct cred *new; | |
876 | gid_t old_fsgid; | |
877 | ||
878 | new = prepare_creds(); | |
879 | if (!new) | |
880 | return current_fsgid(); | |
881 | old = current_cred(); | |
882 | old_fsgid = old->fsgid; | |
1da177e4 | 883 | |
1da177e4 | 884 | if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS)) |
d84f4f99 | 885 | goto error; |
1da177e4 | 886 | |
d84f4f99 DH |
887 | if (gid == old->gid || gid == old->egid || |
888 | gid == old->sgid || gid == old->fsgid || | |
756184b7 CP |
889 | capable(CAP_SETGID)) { |
890 | if (gid != old_fsgid) { | |
d84f4f99 DH |
891 | new->fsgid = gid; |
892 | goto change_okay; | |
1da177e4 | 893 | } |
1da177e4 | 894 | } |
d84f4f99 DH |
895 | |
896 | error: | |
897 | abort_creds(new); | |
898 | return old_fsgid; | |
899 | ||
900 | change_okay: | |
901 | commit_creds(new); | |
1da177e4 LT |
902 | return old_fsgid; |
903 | } | |
904 | ||
f06febc9 FM |
905 | void do_sys_times(struct tms *tms) |
906 | { | |
907 | struct task_cputime cputime; | |
908 | cputime_t cutime, cstime; | |
909 | ||
f06febc9 | 910 | thread_group_cputime(current, &cputime); |
2b5fe6de | 911 | spin_lock_irq(¤t->sighand->siglock); |
f06febc9 FM |
912 | cutime = current->signal->cutime; |
913 | cstime = current->signal->cstime; | |
914 | spin_unlock_irq(¤t->sighand->siglock); | |
915 | tms->tms_utime = cputime_to_clock_t(cputime.utime); | |
916 | tms->tms_stime = cputime_to_clock_t(cputime.stime); | |
917 | tms->tms_cutime = cputime_to_clock_t(cutime); | |
918 | tms->tms_cstime = cputime_to_clock_t(cstime); | |
919 | } | |
920 | ||
1da177e4 LT |
921 | asmlinkage long sys_times(struct tms __user * tbuf) |
922 | { | |
1da177e4 LT |
923 | if (tbuf) { |
924 | struct tms tmp; | |
f06febc9 FM |
925 | |
926 | do_sys_times(&tmp); | |
1da177e4 LT |
927 | if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
928 | return -EFAULT; | |
929 | } | |
930 | return (long) jiffies_64_to_clock_t(get_jiffies_64()); | |
931 | } | |
932 | ||
933 | /* | |
934 | * This needs some heavy checking ... | |
935 | * I just haven't the stomach for it. I also don't fully | |
936 | * understand sessions/pgrp etc. Let somebody who does explain it. | |
937 | * | |
938 | * OK, I think I have the protection semantics right.... this is really | |
939 | * only important on a multi-user system anyway, to make sure one user | |
940 | * can't send a signal to a process owned by another. -TYT, 12/12/91 | |
941 | * | |
942 | * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. | |
943 | * LBT 04.03.94 | |
944 | */ | |
1da177e4 LT |
945 | asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) |
946 | { | |
947 | struct task_struct *p; | |
ee0acf90 | 948 | struct task_struct *group_leader = current->group_leader; |
4e021306 ON |
949 | struct pid *pgrp; |
950 | int err; | |
1da177e4 LT |
951 | |
952 | if (!pid) | |
b488893a | 953 | pid = task_pid_vnr(group_leader); |
1da177e4 LT |
954 | if (!pgid) |
955 | pgid = pid; | |
956 | if (pgid < 0) | |
957 | return -EINVAL; | |
958 | ||
959 | /* From this point forward we keep holding onto the tasklist lock | |
960 | * so that our parent does not change from under us. -DaveM | |
961 | */ | |
962 | write_lock_irq(&tasklist_lock); | |
963 | ||
964 | err = -ESRCH; | |
4e021306 | 965 | p = find_task_by_vpid(pid); |
1da177e4 LT |
966 | if (!p) |
967 | goto out; | |
968 | ||
969 | err = -EINVAL; | |
970 | if (!thread_group_leader(p)) | |
971 | goto out; | |
972 | ||
4e021306 | 973 | if (same_thread_group(p->real_parent, group_leader)) { |
1da177e4 | 974 | err = -EPERM; |
41487c65 | 975 | if (task_session(p) != task_session(group_leader)) |
1da177e4 LT |
976 | goto out; |
977 | err = -EACCES; | |
978 | if (p->did_exec) | |
979 | goto out; | |
980 | } else { | |
981 | err = -ESRCH; | |
ee0acf90 | 982 | if (p != group_leader) |
1da177e4 LT |
983 | goto out; |
984 | } | |
985 | ||
986 | err = -EPERM; | |
987 | if (p->signal->leader) | |
988 | goto out; | |
989 | ||
4e021306 | 990 | pgrp = task_pid(p); |
1da177e4 | 991 | if (pgid != pid) { |
b488893a | 992 | struct task_struct *g; |
1da177e4 | 993 | |
4e021306 ON |
994 | pgrp = find_vpid(pgid); |
995 | g = pid_task(pgrp, PIDTYPE_PGID); | |
41487c65 | 996 | if (!g || task_session(g) != task_session(group_leader)) |
f020bc46 | 997 | goto out; |
1da177e4 LT |
998 | } |
999 | ||
1da177e4 LT |
1000 | err = security_task_setpgid(p, pgid); |
1001 | if (err) | |
1002 | goto out; | |
1003 | ||
4e021306 | 1004 | if (task_pgrp(p) != pgrp) { |
83beaf3c | 1005 | change_pid(p, PIDTYPE_PGID, pgrp); |
4e021306 | 1006 | set_task_pgrp(p, pid_nr(pgrp)); |
1da177e4 LT |
1007 | } |
1008 | ||
1009 | err = 0; | |
1010 | out: | |
1011 | /* All paths lead to here, thus we are safe. -DaveM */ | |
1012 | write_unlock_irq(&tasklist_lock); | |
1013 | return err; | |
1014 | } | |
1015 | ||
1016 | asmlinkage long sys_getpgid(pid_t pid) | |
1017 | { | |
12a3de0a ON |
1018 | struct task_struct *p; |
1019 | struct pid *grp; | |
1020 | int retval; | |
1021 | ||
1022 | rcu_read_lock(); | |
756184b7 | 1023 | if (!pid) |
12a3de0a | 1024 | grp = task_pgrp(current); |
756184b7 | 1025 | else { |
1da177e4 | 1026 | retval = -ESRCH; |
12a3de0a ON |
1027 | p = find_task_by_vpid(pid); |
1028 | if (!p) | |
1029 | goto out; | |
1030 | grp = task_pgrp(p); | |
1031 | if (!grp) | |
1032 | goto out; | |
1033 | ||
1034 | retval = security_task_getpgid(p); | |
1035 | if (retval) | |
1036 | goto out; | |
1da177e4 | 1037 | } |
12a3de0a ON |
1038 | retval = pid_vnr(grp); |
1039 | out: | |
1040 | rcu_read_unlock(); | |
1041 | return retval; | |
1da177e4 LT |
1042 | } |
1043 | ||
1044 | #ifdef __ARCH_WANT_SYS_GETPGRP | |
1045 | ||
1046 | asmlinkage long sys_getpgrp(void) | |
1047 | { | |
12a3de0a | 1048 | return sys_getpgid(0); |
1da177e4 LT |
1049 | } |
1050 | ||
1051 | #endif | |
1052 | ||
1053 | asmlinkage long sys_getsid(pid_t pid) | |
1054 | { | |
1dd768c0 ON |
1055 | struct task_struct *p; |
1056 | struct pid *sid; | |
1057 | int retval; | |
1058 | ||
1059 | rcu_read_lock(); | |
756184b7 | 1060 | if (!pid) |
1dd768c0 | 1061 | sid = task_session(current); |
756184b7 | 1062 | else { |
1da177e4 | 1063 | retval = -ESRCH; |
1dd768c0 ON |
1064 | p = find_task_by_vpid(pid); |
1065 | if (!p) | |
1066 | goto out; | |
1067 | sid = task_session(p); | |
1068 | if (!sid) | |
1069 | goto out; | |
1070 | ||
1071 | retval = security_task_getsid(p); | |
1072 | if (retval) | |
1073 | goto out; | |
1da177e4 | 1074 | } |
1dd768c0 ON |
1075 | retval = pid_vnr(sid); |
1076 | out: | |
1077 | rcu_read_unlock(); | |
1078 | return retval; | |
1da177e4 LT |
1079 | } |
1080 | ||
1081 | asmlinkage long sys_setsid(void) | |
1082 | { | |
e19f247a | 1083 | struct task_struct *group_leader = current->group_leader; |
e4cc0a9c ON |
1084 | struct pid *sid = task_pid(group_leader); |
1085 | pid_t session = pid_vnr(sid); | |
1da177e4 LT |
1086 | int err = -EPERM; |
1087 | ||
1da177e4 | 1088 | write_lock_irq(&tasklist_lock); |
390e2ff0 EB |
1089 | /* Fail if I am already a session leader */ |
1090 | if (group_leader->signal->leader) | |
1091 | goto out; | |
1092 | ||
430c6231 ON |
1093 | /* Fail if a process group id already exists that equals the |
1094 | * proposed session id. | |
390e2ff0 | 1095 | */ |
6806aac6 | 1096 | if (pid_task(sid, PIDTYPE_PGID)) |
1da177e4 LT |
1097 | goto out; |
1098 | ||
e19f247a | 1099 | group_leader->signal->leader = 1; |
8520d7c7 | 1100 | __set_special_pids(sid); |
24ec839c | 1101 | |
9c9f4ded | 1102 | proc_clear_tty(group_leader); |
24ec839c | 1103 | |
e4cc0a9c | 1104 | err = session; |
1da177e4 LT |
1105 | out: |
1106 | write_unlock_irq(&tasklist_lock); | |
1da177e4 LT |
1107 | return err; |
1108 | } | |
1109 | ||
1110 | /* | |
1111 | * Supplementary group IDs | |
1112 | */ | |
1113 | ||
1114 | /* init to 2 - one for init_task, one to ensure it is never freed */ | |
1115 | struct group_info init_groups = { .usage = ATOMIC_INIT(2) }; | |
1116 | ||
1117 | struct group_info *groups_alloc(int gidsetsize) | |
1118 | { | |
1119 | struct group_info *group_info; | |
1120 | int nblocks; | |
1121 | int i; | |
1122 | ||
1123 | nblocks = (gidsetsize + NGROUPS_PER_BLOCK - 1) / NGROUPS_PER_BLOCK; | |
1124 | /* Make sure we always allocate at least one indirect block pointer */ | |
1125 | nblocks = nblocks ? : 1; | |
1126 | group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *), GFP_USER); | |
1127 | if (!group_info) | |
1128 | return NULL; | |
1129 | group_info->ngroups = gidsetsize; | |
1130 | group_info->nblocks = nblocks; | |
1131 | atomic_set(&group_info->usage, 1); | |
1132 | ||
756184b7 | 1133 | if (gidsetsize <= NGROUPS_SMALL) |
1da177e4 | 1134 | group_info->blocks[0] = group_info->small_block; |
756184b7 | 1135 | else { |
1da177e4 LT |
1136 | for (i = 0; i < nblocks; i++) { |
1137 | gid_t *b; | |
1138 | b = (void *)__get_free_page(GFP_USER); | |
1139 | if (!b) | |
1140 | goto out_undo_partial_alloc; | |
1141 | group_info->blocks[i] = b; | |
1142 | } | |
1143 | } | |
1144 | return group_info; | |
1145 | ||
1146 | out_undo_partial_alloc: | |
1147 | while (--i >= 0) { | |
1148 | free_page((unsigned long)group_info->blocks[i]); | |
1149 | } | |
1150 | kfree(group_info); | |
1151 | return NULL; | |
1152 | } | |
1153 | ||
1154 | EXPORT_SYMBOL(groups_alloc); | |
1155 | ||
1156 | void groups_free(struct group_info *group_info) | |
1157 | { | |
1158 | if (group_info->blocks[0] != group_info->small_block) { | |
1159 | int i; | |
1160 | for (i = 0; i < group_info->nblocks; i++) | |
1161 | free_page((unsigned long)group_info->blocks[i]); | |
1162 | } | |
1163 | kfree(group_info); | |
1164 | } | |
1165 | ||
1166 | EXPORT_SYMBOL(groups_free); | |
1167 | ||
1168 | /* export the group_info to a user-space array */ | |
1169 | static int groups_to_user(gid_t __user *grouplist, | |
d84f4f99 | 1170 | const struct group_info *group_info) |
1da177e4 LT |
1171 | { |
1172 | int i; | |
1bf47346 | 1173 | unsigned int count = group_info->ngroups; |
1da177e4 LT |
1174 | |
1175 | for (i = 0; i < group_info->nblocks; i++) { | |
1bf47346 ED |
1176 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
1177 | unsigned int len = cp_count * sizeof(*grouplist); | |
1da177e4 | 1178 | |
1bf47346 | 1179 | if (copy_to_user(grouplist, group_info->blocks[i], len)) |
1da177e4 LT |
1180 | return -EFAULT; |
1181 | ||
1bf47346 | 1182 | grouplist += NGROUPS_PER_BLOCK; |
1da177e4 LT |
1183 | count -= cp_count; |
1184 | } | |
1185 | return 0; | |
1186 | } | |
1187 | ||
1188 | /* fill a group_info from a user-space array - it must be allocated already */ | |
1189 | static int groups_from_user(struct group_info *group_info, | |
1190 | gid_t __user *grouplist) | |
756184b7 | 1191 | { |
1da177e4 | 1192 | int i; |
1bf47346 | 1193 | unsigned int count = group_info->ngroups; |
1da177e4 LT |
1194 | |
1195 | for (i = 0; i < group_info->nblocks; i++) { | |
1bf47346 ED |
1196 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
1197 | unsigned int len = cp_count * sizeof(*grouplist); | |
1da177e4 | 1198 | |
1bf47346 | 1199 | if (copy_from_user(group_info->blocks[i], grouplist, len)) |
1da177e4 LT |
1200 | return -EFAULT; |
1201 | ||
1bf47346 | 1202 | grouplist += NGROUPS_PER_BLOCK; |
1da177e4 LT |
1203 | count -= cp_count; |
1204 | } | |
1205 | return 0; | |
1206 | } | |
1207 | ||
ebe8b541 | 1208 | /* a simple Shell sort */ |
1da177e4 LT |
1209 | static void groups_sort(struct group_info *group_info) |
1210 | { | |
1211 | int base, max, stride; | |
1212 | int gidsetsize = group_info->ngroups; | |
1213 | ||
1214 | for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1) | |
1215 | ; /* nothing */ | |
1216 | stride /= 3; | |
1217 | ||
1218 | while (stride) { | |
1219 | max = gidsetsize - stride; | |
1220 | for (base = 0; base < max; base++) { | |
1221 | int left = base; | |
1222 | int right = left + stride; | |
1223 | gid_t tmp = GROUP_AT(group_info, right); | |
1224 | ||
1225 | while (left >= 0 && GROUP_AT(group_info, left) > tmp) { | |
1226 | GROUP_AT(group_info, right) = | |
1227 | GROUP_AT(group_info, left); | |
1228 | right = left; | |
1229 | left -= stride; | |
1230 | } | |
1231 | GROUP_AT(group_info, right) = tmp; | |
1232 | } | |
1233 | stride /= 3; | |
1234 | } | |
1235 | } | |
1236 | ||
1237 | /* a simple bsearch */ | |
86a264ab | 1238 | int groups_search(const struct group_info *group_info, gid_t grp) |
1da177e4 | 1239 | { |
d74beb9f | 1240 | unsigned int left, right; |
1da177e4 LT |
1241 | |
1242 | if (!group_info) | |
1243 | return 0; | |
1244 | ||
1245 | left = 0; | |
1246 | right = group_info->ngroups; | |
1247 | while (left < right) { | |
d74beb9f | 1248 | unsigned int mid = (left+right)/2; |
1da177e4 LT |
1249 | int cmp = grp - GROUP_AT(group_info, mid); |
1250 | if (cmp > 0) | |
1251 | left = mid + 1; | |
1252 | else if (cmp < 0) | |
1253 | right = mid; | |
1254 | else | |
1255 | return 1; | |
1256 | } | |
1257 | return 0; | |
1258 | } | |
1259 | ||
b6dff3ec | 1260 | /** |
d84f4f99 DH |
1261 | * set_groups - Change a group subscription in a set of credentials |
1262 | * @new: The newly prepared set of credentials to alter | |
1263 | * @group_info: The group list to install | |
b6dff3ec | 1264 | * |
d84f4f99 DH |
1265 | * Validate a group subscription and, if valid, insert it into a set |
1266 | * of credentials. | |
b6dff3ec | 1267 | */ |
d84f4f99 | 1268 | int set_groups(struct cred *new, struct group_info *group_info) |
1da177e4 LT |
1269 | { |
1270 | int retval; | |
1da177e4 LT |
1271 | |
1272 | retval = security_task_setgroups(group_info); | |
1273 | if (retval) | |
1274 | return retval; | |
1275 | ||
d84f4f99 | 1276 | put_group_info(new->group_info); |
1da177e4 LT |
1277 | groups_sort(group_info); |
1278 | get_group_info(group_info); | |
d84f4f99 | 1279 | new->group_info = group_info; |
1da177e4 LT |
1280 | return 0; |
1281 | } | |
1282 | ||
b6dff3ec DH |
1283 | EXPORT_SYMBOL(set_groups); |
1284 | ||
1285 | /** | |
1286 | * set_current_groups - Change current's group subscription | |
1287 | * @group_info: The group list to impose | |
1288 | * | |
1289 | * Validate a group subscription and, if valid, impose it upon current's task | |
1290 | * security record. | |
1291 | */ | |
1292 | int set_current_groups(struct group_info *group_info) | |
1293 | { | |
d84f4f99 DH |
1294 | struct cred *new; |
1295 | int ret; | |
1296 | ||
1297 | new = prepare_creds(); | |
1298 | if (!new) | |
1299 | return -ENOMEM; | |
1300 | ||
1301 | ret = set_groups(new, group_info); | |
1302 | if (ret < 0) { | |
1303 | abort_creds(new); | |
1304 | return ret; | |
1305 | } | |
1306 | ||
1307 | return commit_creds(new); | |
b6dff3ec DH |
1308 | } |
1309 | ||
1da177e4 LT |
1310 | EXPORT_SYMBOL(set_current_groups); |
1311 | ||
1312 | asmlinkage long sys_getgroups(int gidsetsize, gid_t __user *grouplist) | |
1313 | { | |
86a264ab DH |
1314 | const struct cred *cred = current_cred(); |
1315 | int i; | |
1da177e4 LT |
1316 | |
1317 | if (gidsetsize < 0) | |
1318 | return -EINVAL; | |
1319 | ||
1320 | /* no need to grab task_lock here; it cannot change */ | |
b6dff3ec | 1321 | i = cred->group_info->ngroups; |
1da177e4 LT |
1322 | if (gidsetsize) { |
1323 | if (i > gidsetsize) { | |
1324 | i = -EINVAL; | |
1325 | goto out; | |
1326 | } | |
b6dff3ec | 1327 | if (groups_to_user(grouplist, cred->group_info)) { |
1da177e4 LT |
1328 | i = -EFAULT; |
1329 | goto out; | |
1330 | } | |
1331 | } | |
1332 | out: | |
1da177e4 LT |
1333 | return i; |
1334 | } | |
1335 | ||
1336 | /* | |
1337 | * SMP: Our groups are copy-on-write. We can set them safely | |
1338 | * without another task interfering. | |
1339 | */ | |
1340 | ||
1341 | asmlinkage long sys_setgroups(int gidsetsize, gid_t __user *grouplist) | |
1342 | { | |
1343 | struct group_info *group_info; | |
1344 | int retval; | |
1345 | ||
1346 | if (!capable(CAP_SETGID)) | |
1347 | return -EPERM; | |
1348 | if ((unsigned)gidsetsize > NGROUPS_MAX) | |
1349 | return -EINVAL; | |
1350 | ||
1351 | group_info = groups_alloc(gidsetsize); | |
1352 | if (!group_info) | |
1353 | return -ENOMEM; | |
1354 | retval = groups_from_user(group_info, grouplist); | |
1355 | if (retval) { | |
1356 | put_group_info(group_info); | |
1357 | return retval; | |
1358 | } | |
1359 | ||
1360 | retval = set_current_groups(group_info); | |
1361 | put_group_info(group_info); | |
1362 | ||
1363 | return retval; | |
1364 | } | |
1365 | ||
1366 | /* | |
1367 | * Check whether we're fsgid/egid or in the supplemental group.. | |
1368 | */ | |
1369 | int in_group_p(gid_t grp) | |
1370 | { | |
86a264ab | 1371 | const struct cred *cred = current_cred(); |
1da177e4 | 1372 | int retval = 1; |
86a264ab | 1373 | |
b6dff3ec DH |
1374 | if (grp != cred->fsgid) |
1375 | retval = groups_search(cred->group_info, grp); | |
1da177e4 LT |
1376 | return retval; |
1377 | } | |
1378 | ||
1379 | EXPORT_SYMBOL(in_group_p); | |
1380 | ||
1381 | int in_egroup_p(gid_t grp) | |
1382 | { | |
86a264ab | 1383 | const struct cred *cred = current_cred(); |
1da177e4 | 1384 | int retval = 1; |
86a264ab | 1385 | |
b6dff3ec DH |
1386 | if (grp != cred->egid) |
1387 | retval = groups_search(cred->group_info, grp); | |
1da177e4 LT |
1388 | return retval; |
1389 | } | |
1390 | ||
1391 | EXPORT_SYMBOL(in_egroup_p); | |
1392 | ||
1393 | DECLARE_RWSEM(uts_sem); | |
1394 | ||
1da177e4 LT |
1395 | asmlinkage long sys_newuname(struct new_utsname __user * name) |
1396 | { | |
1397 | int errno = 0; | |
1398 | ||
1399 | down_read(&uts_sem); | |
e9ff3990 | 1400 | if (copy_to_user(name, utsname(), sizeof *name)) |
1da177e4 LT |
1401 | errno = -EFAULT; |
1402 | up_read(&uts_sem); | |
1403 | return errno; | |
1404 | } | |
1405 | ||
1406 | asmlinkage long sys_sethostname(char __user *name, int len) | |
1407 | { | |
1408 | int errno; | |
1409 | char tmp[__NEW_UTS_LEN]; | |
1410 | ||
1411 | if (!capable(CAP_SYS_ADMIN)) | |
1412 | return -EPERM; | |
1413 | if (len < 0 || len > __NEW_UTS_LEN) | |
1414 | return -EINVAL; | |
1415 | down_write(&uts_sem); | |
1416 | errno = -EFAULT; | |
1417 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1418 | struct new_utsname *u = utsname(); |
1419 | ||
1420 | memcpy(u->nodename, tmp, len); | |
1421 | memset(u->nodename + len, 0, sizeof(u->nodename) - len); | |
1da177e4 LT |
1422 | errno = 0; |
1423 | } | |
1424 | up_write(&uts_sem); | |
1425 | return errno; | |
1426 | } | |
1427 | ||
1428 | #ifdef __ARCH_WANT_SYS_GETHOSTNAME | |
1429 | ||
1430 | asmlinkage long sys_gethostname(char __user *name, int len) | |
1431 | { | |
1432 | int i, errno; | |
9679e4dd | 1433 | struct new_utsname *u; |
1da177e4 LT |
1434 | |
1435 | if (len < 0) | |
1436 | return -EINVAL; | |
1437 | down_read(&uts_sem); | |
9679e4dd AM |
1438 | u = utsname(); |
1439 | i = 1 + strlen(u->nodename); | |
1da177e4 LT |
1440 | if (i > len) |
1441 | i = len; | |
1442 | errno = 0; | |
9679e4dd | 1443 | if (copy_to_user(name, u->nodename, i)) |
1da177e4 LT |
1444 | errno = -EFAULT; |
1445 | up_read(&uts_sem); | |
1446 | return errno; | |
1447 | } | |
1448 | ||
1449 | #endif | |
1450 | ||
1451 | /* | |
1452 | * Only setdomainname; getdomainname can be implemented by calling | |
1453 | * uname() | |
1454 | */ | |
1455 | asmlinkage long sys_setdomainname(char __user *name, int len) | |
1456 | { | |
1457 | int errno; | |
1458 | char tmp[__NEW_UTS_LEN]; | |
1459 | ||
1460 | if (!capable(CAP_SYS_ADMIN)) | |
1461 | return -EPERM; | |
1462 | if (len < 0 || len > __NEW_UTS_LEN) | |
1463 | return -EINVAL; | |
1464 | ||
1465 | down_write(&uts_sem); | |
1466 | errno = -EFAULT; | |
1467 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1468 | struct new_utsname *u = utsname(); |
1469 | ||
1470 | memcpy(u->domainname, tmp, len); | |
1471 | memset(u->domainname + len, 0, sizeof(u->domainname) - len); | |
1da177e4 LT |
1472 | errno = 0; |
1473 | } | |
1474 | up_write(&uts_sem); | |
1475 | return errno; | |
1476 | } | |
1477 | ||
1478 | asmlinkage long sys_getrlimit(unsigned int resource, struct rlimit __user *rlim) | |
1479 | { | |
1480 | if (resource >= RLIM_NLIMITS) | |
1481 | return -EINVAL; | |
1482 | else { | |
1483 | struct rlimit value; | |
1484 | task_lock(current->group_leader); | |
1485 | value = current->signal->rlim[resource]; | |
1486 | task_unlock(current->group_leader); | |
1487 | return copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; | |
1488 | } | |
1489 | } | |
1490 | ||
1491 | #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT | |
1492 | ||
1493 | /* | |
1494 | * Back compatibility for getrlimit. Needed for some apps. | |
1495 | */ | |
1496 | ||
1497 | asmlinkage long sys_old_getrlimit(unsigned int resource, struct rlimit __user *rlim) | |
1498 | { | |
1499 | struct rlimit x; | |
1500 | if (resource >= RLIM_NLIMITS) | |
1501 | return -EINVAL; | |
1502 | ||
1503 | task_lock(current->group_leader); | |
1504 | x = current->signal->rlim[resource]; | |
1505 | task_unlock(current->group_leader); | |
756184b7 | 1506 | if (x.rlim_cur > 0x7FFFFFFF) |
1da177e4 | 1507 | x.rlim_cur = 0x7FFFFFFF; |
756184b7 | 1508 | if (x.rlim_max > 0x7FFFFFFF) |
1da177e4 LT |
1509 | x.rlim_max = 0x7FFFFFFF; |
1510 | return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0; | |
1511 | } | |
1512 | ||
1513 | #endif | |
1514 | ||
1515 | asmlinkage long sys_setrlimit(unsigned int resource, struct rlimit __user *rlim) | |
1516 | { | |
1517 | struct rlimit new_rlim, *old_rlim; | |
1518 | int retval; | |
1519 | ||
1520 | if (resource >= RLIM_NLIMITS) | |
1521 | return -EINVAL; | |
ec9e16ba | 1522 | if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) |
1da177e4 | 1523 | return -EFAULT; |
1da177e4 LT |
1524 | old_rlim = current->signal->rlim + resource; |
1525 | if ((new_rlim.rlim_max > old_rlim->rlim_max) && | |
1526 | !capable(CAP_SYS_RESOURCE)) | |
1527 | return -EPERM; | |
0c2d64fb AT |
1528 | |
1529 | if (resource == RLIMIT_NOFILE) { | |
1530 | if (new_rlim.rlim_max == RLIM_INFINITY) | |
1531 | new_rlim.rlim_max = sysctl_nr_open; | |
1532 | if (new_rlim.rlim_cur == RLIM_INFINITY) | |
1533 | new_rlim.rlim_cur = sysctl_nr_open; | |
1534 | if (new_rlim.rlim_max > sysctl_nr_open) | |
1535 | return -EPERM; | |
1536 | } | |
1537 | ||
1538 | if (new_rlim.rlim_cur > new_rlim.rlim_max) | |
1539 | return -EINVAL; | |
1da177e4 LT |
1540 | |
1541 | retval = security_task_setrlimit(resource, &new_rlim); | |
1542 | if (retval) | |
1543 | return retval; | |
1544 | ||
9926e4c7 TA |
1545 | if (resource == RLIMIT_CPU && new_rlim.rlim_cur == 0) { |
1546 | /* | |
1547 | * The caller is asking for an immediate RLIMIT_CPU | |
1548 | * expiry. But we use the zero value to mean "it was | |
1549 | * never set". So let's cheat and make it one second | |
1550 | * instead | |
1551 | */ | |
1552 | new_rlim.rlim_cur = 1; | |
1553 | } | |
1554 | ||
1da177e4 LT |
1555 | task_lock(current->group_leader); |
1556 | *old_rlim = new_rlim; | |
1557 | task_unlock(current->group_leader); | |
1558 | ||
ec9e16ba AM |
1559 | if (resource != RLIMIT_CPU) |
1560 | goto out; | |
d3561f78 AM |
1561 | |
1562 | /* | |
1563 | * RLIMIT_CPU handling. Note that the kernel fails to return an error | |
1564 | * code if it rejected the user's attempt to set RLIMIT_CPU. This is a | |
1565 | * very long-standing error, and fixing it now risks breakage of | |
1566 | * applications, so we live with it | |
1567 | */ | |
ec9e16ba AM |
1568 | if (new_rlim.rlim_cur == RLIM_INFINITY) |
1569 | goto out; | |
1570 | ||
f06febc9 | 1571 | update_rlimit_cpu(new_rlim.rlim_cur); |
ec9e16ba | 1572 | out: |
1da177e4 LT |
1573 | return 0; |
1574 | } | |
1575 | ||
1576 | /* | |
1577 | * It would make sense to put struct rusage in the task_struct, | |
1578 | * except that would make the task_struct be *really big*. After | |
1579 | * task_struct gets moved into malloc'ed memory, it would | |
1580 | * make sense to do this. It will make moving the rest of the information | |
1581 | * a lot simpler! (Which we're not doing right now because we're not | |
1582 | * measuring them yet). | |
1583 | * | |
1da177e4 LT |
1584 | * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
1585 | * races with threads incrementing their own counters. But since word | |
1586 | * reads are atomic, we either get new values or old values and we don't | |
1587 | * care which for the sums. We always take the siglock to protect reading | |
1588 | * the c* fields from p->signal from races with exit.c updating those | |
1589 | * fields when reaping, so a sample either gets all the additions of a | |
1590 | * given child after it's reaped, or none so this sample is before reaping. | |
2dd0ebcd | 1591 | * |
de047c1b RT |
1592 | * Locking: |
1593 | * We need to take the siglock for CHILDEREN, SELF and BOTH | |
1594 | * for the cases current multithreaded, non-current single threaded | |
1595 | * non-current multithreaded. Thread traversal is now safe with | |
1596 | * the siglock held. | |
1597 | * Strictly speaking, we donot need to take the siglock if we are current and | |
1598 | * single threaded, as no one else can take our signal_struct away, no one | |
1599 | * else can reap the children to update signal->c* counters, and no one else | |
1600 | * can race with the signal-> fields. If we do not take any lock, the | |
1601 | * signal-> fields could be read out of order while another thread was just | |
1602 | * exiting. So we should place a read memory barrier when we avoid the lock. | |
1603 | * On the writer side, write memory barrier is implied in __exit_signal | |
1604 | * as __exit_signal releases the siglock spinlock after updating the signal-> | |
1605 | * fields. But we don't do this yet to keep things simple. | |
2dd0ebcd | 1606 | * |
1da177e4 LT |
1607 | */ |
1608 | ||
f06febc9 | 1609 | static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) |
679c9cd4 | 1610 | { |
679c9cd4 SK |
1611 | r->ru_nvcsw += t->nvcsw; |
1612 | r->ru_nivcsw += t->nivcsw; | |
1613 | r->ru_minflt += t->min_flt; | |
1614 | r->ru_majflt += t->maj_flt; | |
1615 | r->ru_inblock += task_io_get_inblock(t); | |
1616 | r->ru_oublock += task_io_get_oublock(t); | |
1617 | } | |
1618 | ||
1da177e4 LT |
1619 | static void k_getrusage(struct task_struct *p, int who, struct rusage *r) |
1620 | { | |
1621 | struct task_struct *t; | |
1622 | unsigned long flags; | |
1623 | cputime_t utime, stime; | |
f06febc9 | 1624 | struct task_cputime cputime; |
1da177e4 LT |
1625 | |
1626 | memset((char *) r, 0, sizeof *r); | |
2dd0ebcd | 1627 | utime = stime = cputime_zero; |
1da177e4 | 1628 | |
679c9cd4 | 1629 | if (who == RUSAGE_THREAD) { |
f06febc9 | 1630 | accumulate_thread_rusage(p, r); |
679c9cd4 SK |
1631 | goto out; |
1632 | } | |
1633 | ||
d6cf723a | 1634 | if (!lock_task_sighand(p, &flags)) |
de047c1b | 1635 | return; |
0f59cc4a | 1636 | |
1da177e4 | 1637 | switch (who) { |
0f59cc4a | 1638 | case RUSAGE_BOTH: |
1da177e4 | 1639 | case RUSAGE_CHILDREN: |
1da177e4 LT |
1640 | utime = p->signal->cutime; |
1641 | stime = p->signal->cstime; | |
1642 | r->ru_nvcsw = p->signal->cnvcsw; | |
1643 | r->ru_nivcsw = p->signal->cnivcsw; | |
1644 | r->ru_minflt = p->signal->cmin_flt; | |
1645 | r->ru_majflt = p->signal->cmaj_flt; | |
6eaeeaba ED |
1646 | r->ru_inblock = p->signal->cinblock; |
1647 | r->ru_oublock = p->signal->coublock; | |
0f59cc4a ON |
1648 | |
1649 | if (who == RUSAGE_CHILDREN) | |
1650 | break; | |
1651 | ||
1da177e4 | 1652 | case RUSAGE_SELF: |
f06febc9 FM |
1653 | thread_group_cputime(p, &cputime); |
1654 | utime = cputime_add(utime, cputime.utime); | |
1655 | stime = cputime_add(stime, cputime.stime); | |
1da177e4 LT |
1656 | r->ru_nvcsw += p->signal->nvcsw; |
1657 | r->ru_nivcsw += p->signal->nivcsw; | |
1658 | r->ru_minflt += p->signal->min_flt; | |
1659 | r->ru_majflt += p->signal->maj_flt; | |
6eaeeaba ED |
1660 | r->ru_inblock += p->signal->inblock; |
1661 | r->ru_oublock += p->signal->oublock; | |
1da177e4 LT |
1662 | t = p; |
1663 | do { | |
f06febc9 | 1664 | accumulate_thread_rusage(t, r); |
1da177e4 LT |
1665 | t = next_thread(t); |
1666 | } while (t != p); | |
1da177e4 | 1667 | break; |
0f59cc4a | 1668 | |
1da177e4 LT |
1669 | default: |
1670 | BUG(); | |
1671 | } | |
de047c1b | 1672 | unlock_task_sighand(p, &flags); |
de047c1b | 1673 | |
679c9cd4 | 1674 | out: |
0f59cc4a ON |
1675 | cputime_to_timeval(utime, &r->ru_utime); |
1676 | cputime_to_timeval(stime, &r->ru_stime); | |
1da177e4 LT |
1677 | } |
1678 | ||
1679 | int getrusage(struct task_struct *p, int who, struct rusage __user *ru) | |
1680 | { | |
1681 | struct rusage r; | |
1da177e4 | 1682 | k_getrusage(p, who, &r); |
1da177e4 LT |
1683 | return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
1684 | } | |
1685 | ||
1686 | asmlinkage long sys_getrusage(int who, struct rusage __user *ru) | |
1687 | { | |
679c9cd4 SK |
1688 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
1689 | who != RUSAGE_THREAD) | |
1da177e4 LT |
1690 | return -EINVAL; |
1691 | return getrusage(current, who, ru); | |
1692 | } | |
1693 | ||
1694 | asmlinkage long sys_umask(int mask) | |
1695 | { | |
1696 | mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); | |
1697 | return mask; | |
1698 | } | |
3b7391de | 1699 | |
1da177e4 LT |
1700 | asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3, |
1701 | unsigned long arg4, unsigned long arg5) | |
1702 | { | |
b6dff3ec DH |
1703 | struct task_struct *me = current; |
1704 | unsigned char comm[sizeof(me->comm)]; | |
1705 | long error; | |
1da177e4 | 1706 | |
d84f4f99 DH |
1707 | error = security_task_prctl(option, arg2, arg3, arg4, arg5); |
1708 | if (error != -ENOSYS) | |
1da177e4 LT |
1709 | return error; |
1710 | ||
d84f4f99 | 1711 | error = 0; |
1da177e4 LT |
1712 | switch (option) { |
1713 | case PR_SET_PDEATHSIG: | |
0730ded5 | 1714 | if (!valid_signal(arg2)) { |
1da177e4 LT |
1715 | error = -EINVAL; |
1716 | break; | |
1717 | } | |
b6dff3ec DH |
1718 | me->pdeath_signal = arg2; |
1719 | error = 0; | |
1da177e4 LT |
1720 | break; |
1721 | case PR_GET_PDEATHSIG: | |
b6dff3ec | 1722 | error = put_user(me->pdeath_signal, (int __user *)arg2); |
1da177e4 LT |
1723 | break; |
1724 | case PR_GET_DUMPABLE: | |
b6dff3ec | 1725 | error = get_dumpable(me->mm); |
1da177e4 LT |
1726 | break; |
1727 | case PR_SET_DUMPABLE: | |
abf75a50 | 1728 | if (arg2 < 0 || arg2 > 1) { |
1da177e4 LT |
1729 | error = -EINVAL; |
1730 | break; | |
1731 | } | |
b6dff3ec DH |
1732 | set_dumpable(me->mm, arg2); |
1733 | error = 0; | |
1da177e4 LT |
1734 | break; |
1735 | ||
1736 | case PR_SET_UNALIGN: | |
b6dff3ec | 1737 | error = SET_UNALIGN_CTL(me, arg2); |
1da177e4 LT |
1738 | break; |
1739 | case PR_GET_UNALIGN: | |
b6dff3ec | 1740 | error = GET_UNALIGN_CTL(me, arg2); |
1da177e4 LT |
1741 | break; |
1742 | case PR_SET_FPEMU: | |
b6dff3ec | 1743 | error = SET_FPEMU_CTL(me, arg2); |
1da177e4 LT |
1744 | break; |
1745 | case PR_GET_FPEMU: | |
b6dff3ec | 1746 | error = GET_FPEMU_CTL(me, arg2); |
1da177e4 LT |
1747 | break; |
1748 | case PR_SET_FPEXC: | |
b6dff3ec | 1749 | error = SET_FPEXC_CTL(me, arg2); |
1da177e4 LT |
1750 | break; |
1751 | case PR_GET_FPEXC: | |
b6dff3ec | 1752 | error = GET_FPEXC_CTL(me, arg2); |
1da177e4 LT |
1753 | break; |
1754 | case PR_GET_TIMING: | |
1755 | error = PR_TIMING_STATISTICAL; | |
1756 | break; | |
1757 | case PR_SET_TIMING: | |
7b26655f | 1758 | if (arg2 != PR_TIMING_STATISTICAL) |
1da177e4 | 1759 | error = -EINVAL; |
b6dff3ec DH |
1760 | else |
1761 | error = 0; | |
1da177e4 LT |
1762 | break; |
1763 | ||
b6dff3ec DH |
1764 | case PR_SET_NAME: |
1765 | comm[sizeof(me->comm)-1] = 0; | |
1766 | if (strncpy_from_user(comm, (char __user *)arg2, | |
1767 | sizeof(me->comm) - 1) < 0) | |
1da177e4 | 1768 | return -EFAULT; |
b6dff3ec | 1769 | set_task_comm(me, comm); |
1da177e4 | 1770 | return 0; |
b6dff3ec DH |
1771 | case PR_GET_NAME: |
1772 | get_task_comm(comm, me); | |
1773 | if (copy_to_user((char __user *)arg2, comm, | |
1774 | sizeof(comm))) | |
1da177e4 LT |
1775 | return -EFAULT; |
1776 | return 0; | |
651d765d | 1777 | case PR_GET_ENDIAN: |
b6dff3ec | 1778 | error = GET_ENDIAN(me, arg2); |
651d765d AB |
1779 | break; |
1780 | case PR_SET_ENDIAN: | |
b6dff3ec | 1781 | error = SET_ENDIAN(me, arg2); |
651d765d AB |
1782 | break; |
1783 | ||
1d9d02fe AA |
1784 | case PR_GET_SECCOMP: |
1785 | error = prctl_get_seccomp(); | |
1786 | break; | |
1787 | case PR_SET_SECCOMP: | |
1788 | error = prctl_set_seccomp(arg2); | |
1789 | break; | |
8fb402bc EB |
1790 | case PR_GET_TSC: |
1791 | error = GET_TSC_CTL(arg2); | |
1792 | break; | |
1793 | case PR_SET_TSC: | |
1794 | error = SET_TSC_CTL(arg2); | |
1795 | break; | |
6976675d AV |
1796 | case PR_GET_TIMERSLACK: |
1797 | error = current->timer_slack_ns; | |
1798 | break; | |
1799 | case PR_SET_TIMERSLACK: | |
1800 | if (arg2 <= 0) | |
1801 | current->timer_slack_ns = | |
1802 | current->default_timer_slack_ns; | |
1803 | else | |
1804 | current->timer_slack_ns = arg2; | |
b6dff3ec | 1805 | error = 0; |
6976675d | 1806 | break; |
1da177e4 LT |
1807 | default: |
1808 | error = -EINVAL; | |
1809 | break; | |
1810 | } | |
1811 | return error; | |
1812 | } | |
3cfc348b AK |
1813 | |
1814 | asmlinkage long sys_getcpu(unsigned __user *cpup, unsigned __user *nodep, | |
4307d1e5 | 1815 | struct getcpu_cache __user *unused) |
3cfc348b AK |
1816 | { |
1817 | int err = 0; | |
1818 | int cpu = raw_smp_processor_id(); | |
1819 | if (cpup) | |
1820 | err |= put_user(cpu, cpup); | |
1821 | if (nodep) | |
1822 | err |= put_user(cpu_to_node(cpu), nodep); | |
3cfc348b AK |
1823 | return err ? -EFAULT : 0; |
1824 | } | |
10a0a8d4 JF |
1825 | |
1826 | char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff"; | |
1827 | ||
1828 | static void argv_cleanup(char **argv, char **envp) | |
1829 | { | |
1830 | argv_free(argv); | |
1831 | } | |
1832 | ||
1833 | /** | |
1834 | * orderly_poweroff - Trigger an orderly system poweroff | |
1835 | * @force: force poweroff if command execution fails | |
1836 | * | |
1837 | * This may be called from any context to trigger a system shutdown. | |
1838 | * If the orderly shutdown fails, it will force an immediate shutdown. | |
1839 | */ | |
1840 | int orderly_poweroff(bool force) | |
1841 | { | |
1842 | int argc; | |
1843 | char **argv = argv_split(GFP_ATOMIC, poweroff_cmd, &argc); | |
1844 | static char *envp[] = { | |
1845 | "HOME=/", | |
1846 | "PATH=/sbin:/bin:/usr/sbin:/usr/bin", | |
1847 | NULL | |
1848 | }; | |
1849 | int ret = -ENOMEM; | |
1850 | struct subprocess_info *info; | |
1851 | ||
1852 | if (argv == NULL) { | |
1853 | printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n", | |
1854 | __func__, poweroff_cmd); | |
1855 | goto out; | |
1856 | } | |
1857 | ||
ac331d15 | 1858 | info = call_usermodehelper_setup(argv[0], argv, envp, GFP_ATOMIC); |
10a0a8d4 JF |
1859 | if (info == NULL) { |
1860 | argv_free(argv); | |
1861 | goto out; | |
1862 | } | |
1863 | ||
1864 | call_usermodehelper_setcleanup(info, argv_cleanup); | |
1865 | ||
86313c48 | 1866 | ret = call_usermodehelper_exec(info, UMH_NO_WAIT); |
10a0a8d4 JF |
1867 | |
1868 | out: | |
1869 | if (ret && force) { | |
1870 | printk(KERN_WARNING "Failed to start orderly shutdown: " | |
1871 | "forcing the issue\n"); | |
1872 | ||
1873 | /* I guess this should try to kick off some daemon to | |
1874 | sync and poweroff asap. Or not even bother syncing | |
1875 | if we're doing an emergency shutdown? */ | |
1876 | emergency_sync(); | |
1877 | kernel_power_off(); | |
1878 | } | |
1879 | ||
1880 | return ret; | |
1881 | } | |
1882 | EXPORT_SYMBOL_GPL(orderly_poweroff); |