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Commit | Line | Data |
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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> |
e3d5a27d | 36 | #include <linux/ptrace.h> |
5ad4e53b | 37 | #include <linux/fs_struct.h> |
1da177e4 LT |
38 | |
39 | #include <linux/compat.h> | |
40 | #include <linux/syscalls.h> | |
00d7c05a | 41 | #include <linux/kprobes.h> |
acce292c | 42 | #include <linux/user_namespace.h> |
1da177e4 LT |
43 | |
44 | #include <asm/uaccess.h> | |
45 | #include <asm/io.h> | |
46 | #include <asm/unistd.h> | |
47 | ||
48 | #ifndef SET_UNALIGN_CTL | |
49 | # define SET_UNALIGN_CTL(a,b) (-EINVAL) | |
50 | #endif | |
51 | #ifndef GET_UNALIGN_CTL | |
52 | # define GET_UNALIGN_CTL(a,b) (-EINVAL) | |
53 | #endif | |
54 | #ifndef SET_FPEMU_CTL | |
55 | # define SET_FPEMU_CTL(a,b) (-EINVAL) | |
56 | #endif | |
57 | #ifndef GET_FPEMU_CTL | |
58 | # define GET_FPEMU_CTL(a,b) (-EINVAL) | |
59 | #endif | |
60 | #ifndef SET_FPEXC_CTL | |
61 | # define SET_FPEXC_CTL(a,b) (-EINVAL) | |
62 | #endif | |
63 | #ifndef GET_FPEXC_CTL | |
64 | # define GET_FPEXC_CTL(a,b) (-EINVAL) | |
65 | #endif | |
651d765d AB |
66 | #ifndef GET_ENDIAN |
67 | # define GET_ENDIAN(a,b) (-EINVAL) | |
68 | #endif | |
69 | #ifndef SET_ENDIAN | |
70 | # define SET_ENDIAN(a,b) (-EINVAL) | |
71 | #endif | |
8fb402bc EB |
72 | #ifndef GET_TSC_CTL |
73 | # define GET_TSC_CTL(a) (-EINVAL) | |
74 | #endif | |
75 | #ifndef SET_TSC_CTL | |
76 | # define SET_TSC_CTL(a) (-EINVAL) | |
77 | #endif | |
1da177e4 LT |
78 | |
79 | /* | |
80 | * this is where the system-wide overflow UID and GID are defined, for | |
81 | * architectures that now have 32-bit UID/GID but didn't in the past | |
82 | */ | |
83 | ||
84 | int overflowuid = DEFAULT_OVERFLOWUID; | |
85 | int overflowgid = DEFAULT_OVERFLOWGID; | |
86 | ||
87 | #ifdef CONFIG_UID16 | |
88 | EXPORT_SYMBOL(overflowuid); | |
89 | EXPORT_SYMBOL(overflowgid); | |
90 | #endif | |
91 | ||
92 | /* | |
93 | * the same as above, but for filesystems which can only store a 16-bit | |
94 | * UID and GID. as such, this is needed on all architectures | |
95 | */ | |
96 | ||
97 | int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; | |
98 | int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; | |
99 | ||
100 | EXPORT_SYMBOL(fs_overflowuid); | |
101 | EXPORT_SYMBOL(fs_overflowgid); | |
102 | ||
103 | /* | |
104 | * this indicates whether you can reboot with ctrl-alt-del: the default is yes | |
105 | */ | |
106 | ||
107 | int C_A_D = 1; | |
9ec52099 CLG |
108 | struct pid *cad_pid; |
109 | EXPORT_SYMBOL(cad_pid); | |
1da177e4 | 110 | |
bd804eba RW |
111 | /* |
112 | * If set, this is used for preparing the system to power off. | |
113 | */ | |
114 | ||
115 | void (*pm_power_off_prepare)(void); | |
bd804eba | 116 | |
c69e8d9c DH |
117 | /* |
118 | * set the priority of a task | |
119 | * - the caller must hold the RCU read lock | |
120 | */ | |
1da177e4 LT |
121 | static int set_one_prio(struct task_struct *p, int niceval, int error) |
122 | { | |
c69e8d9c | 123 | const struct cred *cred = current_cred(), *pcred = __task_cred(p); |
1da177e4 LT |
124 | int no_nice; |
125 | ||
c69e8d9c DH |
126 | if (pcred->uid != cred->euid && |
127 | pcred->euid != cred->euid && !capable(CAP_SYS_NICE)) { | |
1da177e4 LT |
128 | error = -EPERM; |
129 | goto out; | |
130 | } | |
e43379f1 | 131 | if (niceval < task_nice(p) && !can_nice(p, niceval)) { |
1da177e4 LT |
132 | error = -EACCES; |
133 | goto out; | |
134 | } | |
135 | no_nice = security_task_setnice(p, niceval); | |
136 | if (no_nice) { | |
137 | error = no_nice; | |
138 | goto out; | |
139 | } | |
140 | if (error == -ESRCH) | |
141 | error = 0; | |
142 | set_user_nice(p, niceval); | |
143 | out: | |
144 | return error; | |
145 | } | |
146 | ||
754fe8d2 | 147 | SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval) |
1da177e4 LT |
148 | { |
149 | struct task_struct *g, *p; | |
150 | struct user_struct *user; | |
86a264ab | 151 | const struct cred *cred = current_cred(); |
1da177e4 | 152 | int error = -EINVAL; |
41487c65 | 153 | struct pid *pgrp; |
1da177e4 | 154 | |
3e88c553 | 155 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
156 | goto out; |
157 | ||
158 | /* normalize: avoid signed division (rounding problems) */ | |
159 | error = -ESRCH; | |
160 | if (niceval < -20) | |
161 | niceval = -20; | |
162 | if (niceval > 19) | |
163 | niceval = 19; | |
164 | ||
165 | read_lock(&tasklist_lock); | |
166 | switch (which) { | |
167 | case PRIO_PROCESS: | |
41487c65 | 168 | if (who) |
228ebcbe | 169 | p = find_task_by_vpid(who); |
41487c65 EB |
170 | else |
171 | p = current; | |
1da177e4 LT |
172 | if (p) |
173 | error = set_one_prio(p, niceval, error); | |
174 | break; | |
175 | case PRIO_PGRP: | |
41487c65 | 176 | if (who) |
b488893a | 177 | pgrp = find_vpid(who); |
41487c65 EB |
178 | else |
179 | pgrp = task_pgrp(current); | |
2d70b68d | 180 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 | 181 | error = set_one_prio(p, niceval, error); |
2d70b68d | 182 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
183 | break; |
184 | case PRIO_USER: | |
d84f4f99 | 185 | user = (struct user_struct *) cred->user; |
1da177e4 | 186 | if (!who) |
86a264ab DH |
187 | who = cred->uid; |
188 | else if ((who != cred->uid) && | |
189 | !(user = find_user(who))) | |
190 | goto out_unlock; /* No processes for this user */ | |
1da177e4 LT |
191 | |
192 | do_each_thread(g, p) | |
86a264ab | 193 | if (__task_cred(p)->uid == who) |
1da177e4 LT |
194 | error = set_one_prio(p, niceval, error); |
195 | while_each_thread(g, p); | |
86a264ab | 196 | if (who != cred->uid) |
1da177e4 LT |
197 | free_uid(user); /* For find_user() */ |
198 | break; | |
199 | } | |
200 | out_unlock: | |
201 | read_unlock(&tasklist_lock); | |
202 | out: | |
203 | return error; | |
204 | } | |
205 | ||
206 | /* | |
207 | * Ugh. To avoid negative return values, "getpriority()" will | |
208 | * not return the normal nice-value, but a negated value that | |
209 | * has been offset by 20 (ie it returns 40..1 instead of -20..19) | |
210 | * to stay compatible. | |
211 | */ | |
754fe8d2 | 212 | SYSCALL_DEFINE2(getpriority, int, which, int, who) |
1da177e4 LT |
213 | { |
214 | struct task_struct *g, *p; | |
215 | struct user_struct *user; | |
86a264ab | 216 | const struct cred *cred = current_cred(); |
1da177e4 | 217 | long niceval, retval = -ESRCH; |
41487c65 | 218 | struct pid *pgrp; |
1da177e4 | 219 | |
3e88c553 | 220 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
221 | return -EINVAL; |
222 | ||
223 | read_lock(&tasklist_lock); | |
224 | switch (which) { | |
225 | case PRIO_PROCESS: | |
41487c65 | 226 | if (who) |
228ebcbe | 227 | p = find_task_by_vpid(who); |
41487c65 EB |
228 | else |
229 | p = current; | |
1da177e4 LT |
230 | if (p) { |
231 | niceval = 20 - task_nice(p); | |
232 | if (niceval > retval) | |
233 | retval = niceval; | |
234 | } | |
235 | break; | |
236 | case PRIO_PGRP: | |
41487c65 | 237 | if (who) |
b488893a | 238 | pgrp = find_vpid(who); |
41487c65 EB |
239 | else |
240 | pgrp = task_pgrp(current); | |
2d70b68d | 241 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 LT |
242 | niceval = 20 - task_nice(p); |
243 | if (niceval > retval) | |
244 | retval = niceval; | |
2d70b68d | 245 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
246 | break; |
247 | case PRIO_USER: | |
86a264ab | 248 | user = (struct user_struct *) cred->user; |
1da177e4 | 249 | if (!who) |
86a264ab DH |
250 | who = cred->uid; |
251 | else if ((who != cred->uid) && | |
252 | !(user = find_user(who))) | |
253 | goto out_unlock; /* No processes for this user */ | |
1da177e4 LT |
254 | |
255 | do_each_thread(g, p) | |
86a264ab | 256 | if (__task_cred(p)->uid == who) { |
1da177e4 LT |
257 | niceval = 20 - task_nice(p); |
258 | if (niceval > retval) | |
259 | retval = niceval; | |
260 | } | |
261 | while_each_thread(g, p); | |
86a264ab | 262 | if (who != cred->uid) |
1da177e4 LT |
263 | free_uid(user); /* for find_user() */ |
264 | break; | |
265 | } | |
266 | out_unlock: | |
267 | read_unlock(&tasklist_lock); | |
268 | ||
269 | return retval; | |
270 | } | |
271 | ||
e4c94330 EB |
272 | /** |
273 | * emergency_restart - reboot the system | |
274 | * | |
275 | * Without shutting down any hardware or taking any locks | |
276 | * reboot the system. This is called when we know we are in | |
277 | * trouble so this is our best effort to reboot. This is | |
278 | * safe to call in interrupt context. | |
279 | */ | |
7c903473 EB |
280 | void emergency_restart(void) |
281 | { | |
282 | machine_emergency_restart(); | |
283 | } | |
284 | EXPORT_SYMBOL_GPL(emergency_restart); | |
285 | ||
ca195b7f | 286 | void kernel_restart_prepare(char *cmd) |
4a00ea1e | 287 | { |
e041c683 | 288 | blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd); |
4a00ea1e | 289 | system_state = SYSTEM_RESTART; |
4a00ea1e | 290 | device_shutdown(); |
58b3b71d | 291 | sysdev_shutdown(); |
e4c94330 | 292 | } |
1e5d5331 RD |
293 | |
294 | /** | |
295 | * kernel_restart - reboot the system | |
296 | * @cmd: pointer to buffer containing command to execute for restart | |
b8887e6e | 297 | * or %NULL |
1e5d5331 RD |
298 | * |
299 | * Shutdown everything and perform a clean reboot. | |
300 | * This is not safe to call in interrupt context. | |
301 | */ | |
e4c94330 EB |
302 | void kernel_restart(char *cmd) |
303 | { | |
304 | kernel_restart_prepare(cmd); | |
756184b7 | 305 | if (!cmd) |
4a00ea1e | 306 | printk(KERN_EMERG "Restarting system.\n"); |
756184b7 | 307 | else |
4a00ea1e | 308 | printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd); |
4a00ea1e EB |
309 | machine_restart(cmd); |
310 | } | |
311 | EXPORT_SYMBOL_GPL(kernel_restart); | |
312 | ||
4ef7229f | 313 | static void kernel_shutdown_prepare(enum system_states state) |
729b4d4c | 314 | { |
e041c683 | 315 | blocking_notifier_call_chain(&reboot_notifier_list, |
729b4d4c AS |
316 | (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL); |
317 | system_state = state; | |
318 | device_shutdown(); | |
319 | } | |
e4c94330 EB |
320 | /** |
321 | * kernel_halt - halt the system | |
322 | * | |
323 | * Shutdown everything and perform a clean system halt. | |
324 | */ | |
e4c94330 EB |
325 | void kernel_halt(void) |
326 | { | |
729b4d4c | 327 | kernel_shutdown_prepare(SYSTEM_HALT); |
58b3b71d | 328 | sysdev_shutdown(); |
4a00ea1e EB |
329 | printk(KERN_EMERG "System halted.\n"); |
330 | machine_halt(); | |
331 | } | |
729b4d4c | 332 | |
4a00ea1e EB |
333 | EXPORT_SYMBOL_GPL(kernel_halt); |
334 | ||
e4c94330 EB |
335 | /** |
336 | * kernel_power_off - power_off the system | |
337 | * | |
338 | * Shutdown everything and perform a clean system power_off. | |
339 | */ | |
e4c94330 EB |
340 | void kernel_power_off(void) |
341 | { | |
729b4d4c | 342 | kernel_shutdown_prepare(SYSTEM_POWER_OFF); |
bd804eba RW |
343 | if (pm_power_off_prepare) |
344 | pm_power_off_prepare(); | |
4047727e | 345 | disable_nonboot_cpus(); |
58b3b71d | 346 | sysdev_shutdown(); |
4a00ea1e EB |
347 | printk(KERN_EMERG "Power down.\n"); |
348 | machine_power_off(); | |
349 | } | |
350 | EXPORT_SYMBOL_GPL(kernel_power_off); | |
1da177e4 LT |
351 | /* |
352 | * Reboot system call: for obvious reasons only root may call it, | |
353 | * and even root needs to set up some magic numbers in the registers | |
354 | * so that some mistake won't make this reboot the whole machine. | |
355 | * You can also set the meaning of the ctrl-alt-del-key here. | |
356 | * | |
357 | * reboot doesn't sync: do that yourself before calling this. | |
358 | */ | |
754fe8d2 HC |
359 | SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, |
360 | void __user *, arg) | |
1da177e4 LT |
361 | { |
362 | char buffer[256]; | |
363 | ||
364 | /* We only trust the superuser with rebooting the system. */ | |
365 | if (!capable(CAP_SYS_BOOT)) | |
366 | return -EPERM; | |
367 | ||
368 | /* For safety, we require "magic" arguments. */ | |
369 | if (magic1 != LINUX_REBOOT_MAGIC1 || | |
370 | (magic2 != LINUX_REBOOT_MAGIC2 && | |
371 | magic2 != LINUX_REBOOT_MAGIC2A && | |
372 | magic2 != LINUX_REBOOT_MAGIC2B && | |
373 | magic2 != LINUX_REBOOT_MAGIC2C)) | |
374 | return -EINVAL; | |
375 | ||
5e38291d EB |
376 | /* Instead of trying to make the power_off code look like |
377 | * halt when pm_power_off is not set do it the easy way. | |
378 | */ | |
379 | if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off) | |
380 | cmd = LINUX_REBOOT_CMD_HALT; | |
381 | ||
1da177e4 LT |
382 | lock_kernel(); |
383 | switch (cmd) { | |
384 | case LINUX_REBOOT_CMD_RESTART: | |
4a00ea1e | 385 | kernel_restart(NULL); |
1da177e4 LT |
386 | break; |
387 | ||
388 | case LINUX_REBOOT_CMD_CAD_ON: | |
389 | C_A_D = 1; | |
390 | break; | |
391 | ||
392 | case LINUX_REBOOT_CMD_CAD_OFF: | |
393 | C_A_D = 0; | |
394 | break; | |
395 | ||
396 | case LINUX_REBOOT_CMD_HALT: | |
4a00ea1e | 397 | kernel_halt(); |
1da177e4 LT |
398 | unlock_kernel(); |
399 | do_exit(0); | |
400 | break; | |
401 | ||
402 | case LINUX_REBOOT_CMD_POWER_OFF: | |
4a00ea1e | 403 | kernel_power_off(); |
1da177e4 LT |
404 | unlock_kernel(); |
405 | do_exit(0); | |
406 | break; | |
407 | ||
408 | case LINUX_REBOOT_CMD_RESTART2: | |
409 | if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) { | |
410 | unlock_kernel(); | |
411 | return -EFAULT; | |
412 | } | |
413 | buffer[sizeof(buffer) - 1] = '\0'; | |
414 | ||
4a00ea1e | 415 | kernel_restart(buffer); |
1da177e4 LT |
416 | break; |
417 | ||
3ab83521 | 418 | #ifdef CONFIG_KEXEC |
dc009d92 | 419 | case LINUX_REBOOT_CMD_KEXEC: |
3ab83521 HY |
420 | { |
421 | int ret; | |
422 | ret = kernel_kexec(); | |
423 | unlock_kernel(); | |
424 | return ret; | |
425 | } | |
426 | #endif | |
4a00ea1e | 427 | |
b0cb1a19 | 428 | #ifdef CONFIG_HIBERNATION |
1da177e4 LT |
429 | case LINUX_REBOOT_CMD_SW_SUSPEND: |
430 | { | |
a3d25c27 | 431 | int ret = hibernate(); |
1da177e4 LT |
432 | unlock_kernel(); |
433 | return ret; | |
434 | } | |
435 | #endif | |
436 | ||
437 | default: | |
438 | unlock_kernel(); | |
439 | return -EINVAL; | |
440 | } | |
441 | unlock_kernel(); | |
442 | return 0; | |
443 | } | |
444 | ||
65f27f38 | 445 | static void deferred_cad(struct work_struct *dummy) |
1da177e4 | 446 | { |
abcd9e51 | 447 | kernel_restart(NULL); |
1da177e4 LT |
448 | } |
449 | ||
450 | /* | |
451 | * This function gets called by ctrl-alt-del - ie the keyboard interrupt. | |
452 | * As it's called within an interrupt, it may NOT sync: the only choice | |
453 | * is whether to reboot at once, or just ignore the ctrl-alt-del. | |
454 | */ | |
455 | void ctrl_alt_del(void) | |
456 | { | |
65f27f38 | 457 | static DECLARE_WORK(cad_work, deferred_cad); |
1da177e4 LT |
458 | |
459 | if (C_A_D) | |
460 | schedule_work(&cad_work); | |
461 | else | |
9ec52099 | 462 | kill_cad_pid(SIGINT, 1); |
1da177e4 LT |
463 | } |
464 | ||
1da177e4 LT |
465 | /* |
466 | * Unprivileged users may change the real gid to the effective gid | |
467 | * or vice versa. (BSD-style) | |
468 | * | |
469 | * If you set the real gid at all, or set the effective gid to a value not | |
470 | * equal to the real gid, then the saved gid is set to the new effective gid. | |
471 | * | |
472 | * This makes it possible for a setgid program to completely drop its | |
473 | * privileges, which is often a useful assertion to make when you are doing | |
474 | * a security audit over a program. | |
475 | * | |
476 | * The general idea is that a program which uses just setregid() will be | |
477 | * 100% compatible with BSD. A program which uses just setgid() will be | |
478 | * 100% compatible with POSIX with saved IDs. | |
479 | * | |
480 | * SMP: There are not races, the GIDs are checked only by filesystem | |
481 | * operations (as far as semantic preservation is concerned). | |
482 | */ | |
ae1251ab | 483 | SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) |
1da177e4 | 484 | { |
d84f4f99 DH |
485 | const struct cred *old; |
486 | struct cred *new; | |
1da177e4 LT |
487 | int retval; |
488 | ||
d84f4f99 DH |
489 | new = prepare_creds(); |
490 | if (!new) | |
491 | return -ENOMEM; | |
492 | old = current_cred(); | |
493 | ||
1da177e4 LT |
494 | retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE); |
495 | if (retval) | |
d84f4f99 | 496 | goto error; |
1da177e4 | 497 | |
d84f4f99 | 498 | retval = -EPERM; |
1da177e4 | 499 | if (rgid != (gid_t) -1) { |
d84f4f99 DH |
500 | if (old->gid == rgid || |
501 | old->egid == rgid || | |
1da177e4 | 502 | capable(CAP_SETGID)) |
d84f4f99 | 503 | new->gid = rgid; |
1da177e4 | 504 | else |
d84f4f99 | 505 | goto error; |
1da177e4 LT |
506 | } |
507 | if (egid != (gid_t) -1) { | |
d84f4f99 DH |
508 | if (old->gid == egid || |
509 | old->egid == egid || | |
510 | old->sgid == egid || | |
1da177e4 | 511 | capable(CAP_SETGID)) |
d84f4f99 | 512 | new->egid = egid; |
756184b7 | 513 | else |
d84f4f99 | 514 | goto error; |
1da177e4 | 515 | } |
d84f4f99 | 516 | |
1da177e4 | 517 | if (rgid != (gid_t) -1 || |
d84f4f99 DH |
518 | (egid != (gid_t) -1 && egid != old->gid)) |
519 | new->sgid = new->egid; | |
520 | new->fsgid = new->egid; | |
521 | ||
522 | return commit_creds(new); | |
523 | ||
524 | error: | |
525 | abort_creds(new); | |
526 | return retval; | |
1da177e4 LT |
527 | } |
528 | ||
529 | /* | |
530 | * setgid() is implemented like SysV w/ SAVED_IDS | |
531 | * | |
532 | * SMP: Same implicit races as above. | |
533 | */ | |
ae1251ab | 534 | SYSCALL_DEFINE1(setgid, gid_t, gid) |
1da177e4 | 535 | { |
d84f4f99 DH |
536 | const struct cred *old; |
537 | struct cred *new; | |
1da177e4 LT |
538 | int retval; |
539 | ||
d84f4f99 DH |
540 | new = prepare_creds(); |
541 | if (!new) | |
542 | return -ENOMEM; | |
543 | old = current_cred(); | |
544 | ||
1da177e4 LT |
545 | retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID); |
546 | if (retval) | |
d84f4f99 | 547 | goto error; |
1da177e4 | 548 | |
d84f4f99 DH |
549 | retval = -EPERM; |
550 | if (capable(CAP_SETGID)) | |
551 | new->gid = new->egid = new->sgid = new->fsgid = gid; | |
552 | else if (gid == old->gid || gid == old->sgid) | |
553 | new->egid = new->fsgid = gid; | |
1da177e4 | 554 | else |
d84f4f99 | 555 | goto error; |
1da177e4 | 556 | |
d84f4f99 DH |
557 | return commit_creds(new); |
558 | ||
559 | error: | |
560 | abort_creds(new); | |
561 | return retval; | |
1da177e4 | 562 | } |
54e99124 | 563 | |
d84f4f99 DH |
564 | /* |
565 | * change the user struct in a credentials set to match the new UID | |
566 | */ | |
567 | static int set_user(struct cred *new) | |
1da177e4 LT |
568 | { |
569 | struct user_struct *new_user; | |
570 | ||
18b6e041 | 571 | new_user = alloc_uid(current_user_ns(), new->uid); |
1da177e4 LT |
572 | if (!new_user) |
573 | return -EAGAIN; | |
574 | ||
54e99124 DG |
575 | if (!task_can_switch_user(new_user, current)) { |
576 | free_uid(new_user); | |
577 | return -EINVAL; | |
578 | } | |
579 | ||
1da177e4 LT |
580 | if (atomic_read(&new_user->processes) >= |
581 | current->signal->rlim[RLIMIT_NPROC].rlim_cur && | |
18b6e041 | 582 | new_user != INIT_USER) { |
1da177e4 LT |
583 | free_uid(new_user); |
584 | return -EAGAIN; | |
585 | } | |
586 | ||
d84f4f99 DH |
587 | free_uid(new->user); |
588 | new->user = new_user; | |
1da177e4 LT |
589 | return 0; |
590 | } | |
591 | ||
592 | /* | |
593 | * Unprivileged users may change the real uid to the effective uid | |
594 | * or vice versa. (BSD-style) | |
595 | * | |
596 | * If you set the real uid at all, or set the effective uid to a value not | |
597 | * equal to the real uid, then the saved uid is set to the new effective uid. | |
598 | * | |
599 | * This makes it possible for a setuid program to completely drop its | |
600 | * privileges, which is often a useful assertion to make when you are doing | |
601 | * a security audit over a program. | |
602 | * | |
603 | * The general idea is that a program which uses just setreuid() will be | |
604 | * 100% compatible with BSD. A program which uses just setuid() will be | |
605 | * 100% compatible with POSIX with saved IDs. | |
606 | */ | |
ae1251ab | 607 | SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) |
1da177e4 | 608 | { |
d84f4f99 DH |
609 | const struct cred *old; |
610 | struct cred *new; | |
1da177e4 LT |
611 | int retval; |
612 | ||
d84f4f99 DH |
613 | new = prepare_creds(); |
614 | if (!new) | |
615 | return -ENOMEM; | |
616 | old = current_cred(); | |
617 | ||
1da177e4 LT |
618 | retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE); |
619 | if (retval) | |
d84f4f99 | 620 | goto error; |
1da177e4 | 621 | |
d84f4f99 | 622 | retval = -EPERM; |
1da177e4 | 623 | if (ruid != (uid_t) -1) { |
d84f4f99 DH |
624 | new->uid = ruid; |
625 | if (old->uid != ruid && | |
626 | old->euid != ruid && | |
1da177e4 | 627 | !capable(CAP_SETUID)) |
d84f4f99 | 628 | goto error; |
1da177e4 LT |
629 | } |
630 | ||
631 | if (euid != (uid_t) -1) { | |
d84f4f99 DH |
632 | new->euid = euid; |
633 | if (old->uid != euid && | |
634 | old->euid != euid && | |
635 | old->suid != euid && | |
1da177e4 | 636 | !capable(CAP_SETUID)) |
d84f4f99 | 637 | goto error; |
1da177e4 LT |
638 | } |
639 | ||
54e99124 DG |
640 | if (new->uid != old->uid) { |
641 | retval = set_user(new); | |
642 | if (retval < 0) | |
643 | goto error; | |
644 | } | |
1da177e4 | 645 | if (ruid != (uid_t) -1 || |
d84f4f99 DH |
646 | (euid != (uid_t) -1 && euid != old->uid)) |
647 | new->suid = new->euid; | |
648 | new->fsuid = new->euid; | |
1da177e4 | 649 | |
d84f4f99 DH |
650 | retval = security_task_fix_setuid(new, old, LSM_SETID_RE); |
651 | if (retval < 0) | |
652 | goto error; | |
1da177e4 | 653 | |
d84f4f99 | 654 | return commit_creds(new); |
1da177e4 | 655 | |
d84f4f99 DH |
656 | error: |
657 | abort_creds(new); | |
658 | return retval; | |
659 | } | |
1da177e4 LT |
660 | |
661 | /* | |
662 | * setuid() is implemented like SysV with SAVED_IDS | |
663 | * | |
664 | * Note that SAVED_ID's is deficient in that a setuid root program | |
665 | * like sendmail, for example, cannot set its uid to be a normal | |
666 | * user and then switch back, because if you're root, setuid() sets | |
667 | * the saved uid too. If you don't like this, blame the bright people | |
668 | * in the POSIX committee and/or USG. Note that the BSD-style setreuid() | |
669 | * will allow a root program to temporarily drop privileges and be able to | |
670 | * regain them by swapping the real and effective uid. | |
671 | */ | |
ae1251ab | 672 | SYSCALL_DEFINE1(setuid, uid_t, uid) |
1da177e4 | 673 | { |
d84f4f99 DH |
674 | const struct cred *old; |
675 | struct cred *new; | |
1da177e4 LT |
676 | int retval; |
677 | ||
d84f4f99 DH |
678 | new = prepare_creds(); |
679 | if (!new) | |
680 | return -ENOMEM; | |
681 | old = current_cred(); | |
682 | ||
1da177e4 LT |
683 | retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID); |
684 | if (retval) | |
d84f4f99 | 685 | goto error; |
1da177e4 | 686 | |
d84f4f99 | 687 | retval = -EPERM; |
1da177e4 | 688 | if (capable(CAP_SETUID)) { |
d84f4f99 | 689 | new->suid = new->uid = uid; |
54e99124 DG |
690 | if (uid != old->uid) { |
691 | retval = set_user(new); | |
692 | if (retval < 0) | |
693 | goto error; | |
d84f4f99 DH |
694 | } |
695 | } else if (uid != old->uid && uid != new->suid) { | |
696 | goto error; | |
1da177e4 | 697 | } |
1da177e4 | 698 | |
d84f4f99 DH |
699 | new->fsuid = new->euid = uid; |
700 | ||
701 | retval = security_task_fix_setuid(new, old, LSM_SETID_ID); | |
702 | if (retval < 0) | |
703 | goto error; | |
704 | ||
705 | return commit_creds(new); | |
1da177e4 | 706 | |
d84f4f99 DH |
707 | error: |
708 | abort_creds(new); | |
709 | return retval; | |
1da177e4 LT |
710 | } |
711 | ||
712 | ||
713 | /* | |
714 | * This function implements a generic ability to update ruid, euid, | |
715 | * and suid. This allows you to implement the 4.4 compatible seteuid(). | |
716 | */ | |
ae1251ab | 717 | SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) |
1da177e4 | 718 | { |
d84f4f99 DH |
719 | const struct cred *old; |
720 | struct cred *new; | |
1da177e4 LT |
721 | int retval; |
722 | ||
d84f4f99 DH |
723 | new = prepare_creds(); |
724 | if (!new) | |
725 | return -ENOMEM; | |
726 | ||
1da177e4 LT |
727 | retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES); |
728 | if (retval) | |
d84f4f99 DH |
729 | goto error; |
730 | old = current_cred(); | |
1da177e4 | 731 | |
d84f4f99 | 732 | retval = -EPERM; |
1da177e4 | 733 | if (!capable(CAP_SETUID)) { |
d84f4f99 DH |
734 | if (ruid != (uid_t) -1 && ruid != old->uid && |
735 | ruid != old->euid && ruid != old->suid) | |
736 | goto error; | |
737 | if (euid != (uid_t) -1 && euid != old->uid && | |
738 | euid != old->euid && euid != old->suid) | |
739 | goto error; | |
740 | if (suid != (uid_t) -1 && suid != old->uid && | |
741 | suid != old->euid && suid != old->suid) | |
742 | goto error; | |
1da177e4 | 743 | } |
d84f4f99 | 744 | |
1da177e4 | 745 | if (ruid != (uid_t) -1) { |
d84f4f99 | 746 | new->uid = ruid; |
54e99124 DG |
747 | if (ruid != old->uid) { |
748 | retval = set_user(new); | |
749 | if (retval < 0) | |
750 | goto error; | |
751 | } | |
1da177e4 | 752 | } |
d84f4f99 DH |
753 | if (euid != (uid_t) -1) |
754 | new->euid = euid; | |
1da177e4 | 755 | if (suid != (uid_t) -1) |
d84f4f99 DH |
756 | new->suid = suid; |
757 | new->fsuid = new->euid; | |
1da177e4 | 758 | |
d84f4f99 DH |
759 | retval = security_task_fix_setuid(new, old, LSM_SETID_RES); |
760 | if (retval < 0) | |
761 | goto error; | |
1da177e4 | 762 | |
d84f4f99 DH |
763 | return commit_creds(new); |
764 | ||
765 | error: | |
766 | abort_creds(new); | |
767 | return retval; | |
1da177e4 LT |
768 | } |
769 | ||
dbf040d9 | 770 | SYSCALL_DEFINE3(getresuid, uid_t __user *, ruid, uid_t __user *, euid, uid_t __user *, suid) |
1da177e4 | 771 | { |
86a264ab | 772 | const struct cred *cred = current_cred(); |
1da177e4 LT |
773 | int retval; |
774 | ||
86a264ab DH |
775 | if (!(retval = put_user(cred->uid, ruid)) && |
776 | !(retval = put_user(cred->euid, euid))) | |
b6dff3ec | 777 | retval = put_user(cred->suid, suid); |
1da177e4 LT |
778 | |
779 | return retval; | |
780 | } | |
781 | ||
782 | /* | |
783 | * Same as above, but for rgid, egid, sgid. | |
784 | */ | |
ae1251ab | 785 | SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) |
1da177e4 | 786 | { |
d84f4f99 DH |
787 | const struct cred *old; |
788 | struct cred *new; | |
1da177e4 LT |
789 | int retval; |
790 | ||
d84f4f99 DH |
791 | new = prepare_creds(); |
792 | if (!new) | |
793 | return -ENOMEM; | |
794 | old = current_cred(); | |
795 | ||
1da177e4 LT |
796 | retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES); |
797 | if (retval) | |
d84f4f99 | 798 | goto error; |
1da177e4 | 799 | |
d84f4f99 | 800 | retval = -EPERM; |
1da177e4 | 801 | if (!capable(CAP_SETGID)) { |
d84f4f99 DH |
802 | if (rgid != (gid_t) -1 && rgid != old->gid && |
803 | rgid != old->egid && rgid != old->sgid) | |
804 | goto error; | |
805 | if (egid != (gid_t) -1 && egid != old->gid && | |
806 | egid != old->egid && egid != old->sgid) | |
807 | goto error; | |
808 | if (sgid != (gid_t) -1 && sgid != old->gid && | |
809 | sgid != old->egid && sgid != old->sgid) | |
810 | goto error; | |
1da177e4 | 811 | } |
d84f4f99 | 812 | |
1da177e4 | 813 | if (rgid != (gid_t) -1) |
d84f4f99 DH |
814 | new->gid = rgid; |
815 | if (egid != (gid_t) -1) | |
816 | new->egid = egid; | |
1da177e4 | 817 | if (sgid != (gid_t) -1) |
d84f4f99 DH |
818 | new->sgid = sgid; |
819 | new->fsgid = new->egid; | |
1da177e4 | 820 | |
d84f4f99 DH |
821 | return commit_creds(new); |
822 | ||
823 | error: | |
824 | abort_creds(new); | |
825 | return retval; | |
1da177e4 LT |
826 | } |
827 | ||
dbf040d9 | 828 | SYSCALL_DEFINE3(getresgid, gid_t __user *, rgid, gid_t __user *, egid, gid_t __user *, sgid) |
1da177e4 | 829 | { |
86a264ab | 830 | const struct cred *cred = current_cred(); |
1da177e4 LT |
831 | int retval; |
832 | ||
86a264ab DH |
833 | if (!(retval = put_user(cred->gid, rgid)) && |
834 | !(retval = put_user(cred->egid, egid))) | |
b6dff3ec | 835 | retval = put_user(cred->sgid, sgid); |
1da177e4 LT |
836 | |
837 | return retval; | |
838 | } | |
839 | ||
840 | ||
841 | /* | |
842 | * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This | |
843 | * is used for "access()" and for the NFS daemon (letting nfsd stay at | |
844 | * whatever uid it wants to). It normally shadows "euid", except when | |
845 | * explicitly set by setfsuid() or for access.. | |
846 | */ | |
ae1251ab | 847 | SYSCALL_DEFINE1(setfsuid, uid_t, uid) |
1da177e4 | 848 | { |
d84f4f99 DH |
849 | const struct cred *old; |
850 | struct cred *new; | |
851 | uid_t old_fsuid; | |
852 | ||
853 | new = prepare_creds(); | |
854 | if (!new) | |
855 | return current_fsuid(); | |
856 | old = current_cred(); | |
857 | old_fsuid = old->fsuid; | |
1da177e4 | 858 | |
d84f4f99 DH |
859 | if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS) < 0) |
860 | goto error; | |
1da177e4 | 861 | |
d84f4f99 DH |
862 | if (uid == old->uid || uid == old->euid || |
863 | uid == old->suid || uid == old->fsuid || | |
756184b7 CP |
864 | capable(CAP_SETUID)) { |
865 | if (uid != old_fsuid) { | |
d84f4f99 DH |
866 | new->fsuid = uid; |
867 | if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) | |
868 | goto change_okay; | |
1da177e4 | 869 | } |
1da177e4 LT |
870 | } |
871 | ||
d84f4f99 DH |
872 | error: |
873 | abort_creds(new); | |
874 | return old_fsuid; | |
1da177e4 | 875 | |
d84f4f99 DH |
876 | change_okay: |
877 | commit_creds(new); | |
1da177e4 LT |
878 | return old_fsuid; |
879 | } | |
880 | ||
881 | /* | |
f42df9e6 | 882 | * Samma på svenska.. |
1da177e4 | 883 | */ |
ae1251ab | 884 | SYSCALL_DEFINE1(setfsgid, gid_t, gid) |
1da177e4 | 885 | { |
d84f4f99 DH |
886 | const struct cred *old; |
887 | struct cred *new; | |
888 | gid_t old_fsgid; | |
889 | ||
890 | new = prepare_creds(); | |
891 | if (!new) | |
892 | return current_fsgid(); | |
893 | old = current_cred(); | |
894 | old_fsgid = old->fsgid; | |
1da177e4 | 895 | |
1da177e4 | 896 | if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS)) |
d84f4f99 | 897 | goto error; |
1da177e4 | 898 | |
d84f4f99 DH |
899 | if (gid == old->gid || gid == old->egid || |
900 | gid == old->sgid || gid == old->fsgid || | |
756184b7 CP |
901 | capable(CAP_SETGID)) { |
902 | if (gid != old_fsgid) { | |
d84f4f99 DH |
903 | new->fsgid = gid; |
904 | goto change_okay; | |
1da177e4 | 905 | } |
1da177e4 | 906 | } |
d84f4f99 DH |
907 | |
908 | error: | |
909 | abort_creds(new); | |
910 | return old_fsgid; | |
911 | ||
912 | change_okay: | |
913 | commit_creds(new); | |
1da177e4 LT |
914 | return old_fsgid; |
915 | } | |
916 | ||
f06febc9 FM |
917 | void do_sys_times(struct tms *tms) |
918 | { | |
919 | struct task_cputime cputime; | |
920 | cputime_t cutime, cstime; | |
921 | ||
f06febc9 | 922 | thread_group_cputime(current, &cputime); |
2b5fe6de | 923 | spin_lock_irq(¤t->sighand->siglock); |
f06febc9 FM |
924 | cutime = current->signal->cutime; |
925 | cstime = current->signal->cstime; | |
926 | spin_unlock_irq(¤t->sighand->siglock); | |
927 | tms->tms_utime = cputime_to_clock_t(cputime.utime); | |
928 | tms->tms_stime = cputime_to_clock_t(cputime.stime); | |
929 | tms->tms_cutime = cputime_to_clock_t(cutime); | |
930 | tms->tms_cstime = cputime_to_clock_t(cstime); | |
931 | } | |
932 | ||
58fd3aa2 | 933 | SYSCALL_DEFINE1(times, struct tms __user *, tbuf) |
1da177e4 | 934 | { |
1da177e4 LT |
935 | if (tbuf) { |
936 | struct tms tmp; | |
f06febc9 FM |
937 | |
938 | do_sys_times(&tmp); | |
1da177e4 LT |
939 | if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
940 | return -EFAULT; | |
941 | } | |
e3d5a27d | 942 | force_successful_syscall_return(); |
1da177e4 LT |
943 | return (long) jiffies_64_to_clock_t(get_jiffies_64()); |
944 | } | |
945 | ||
946 | /* | |
947 | * This needs some heavy checking ... | |
948 | * I just haven't the stomach for it. I also don't fully | |
949 | * understand sessions/pgrp etc. Let somebody who does explain it. | |
950 | * | |
951 | * OK, I think I have the protection semantics right.... this is really | |
952 | * only important on a multi-user system anyway, to make sure one user | |
953 | * can't send a signal to a process owned by another. -TYT, 12/12/91 | |
954 | * | |
955 | * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. | |
956 | * LBT 04.03.94 | |
957 | */ | |
b290ebe2 | 958 | SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) |
1da177e4 LT |
959 | { |
960 | struct task_struct *p; | |
ee0acf90 | 961 | struct task_struct *group_leader = current->group_leader; |
4e021306 ON |
962 | struct pid *pgrp; |
963 | int err; | |
1da177e4 LT |
964 | |
965 | if (!pid) | |
b488893a | 966 | pid = task_pid_vnr(group_leader); |
1da177e4 LT |
967 | if (!pgid) |
968 | pgid = pid; | |
969 | if (pgid < 0) | |
970 | return -EINVAL; | |
971 | ||
972 | /* From this point forward we keep holding onto the tasklist lock | |
973 | * so that our parent does not change from under us. -DaveM | |
974 | */ | |
975 | write_lock_irq(&tasklist_lock); | |
976 | ||
977 | err = -ESRCH; | |
4e021306 | 978 | p = find_task_by_vpid(pid); |
1da177e4 LT |
979 | if (!p) |
980 | goto out; | |
981 | ||
982 | err = -EINVAL; | |
983 | if (!thread_group_leader(p)) | |
984 | goto out; | |
985 | ||
4e021306 | 986 | if (same_thread_group(p->real_parent, group_leader)) { |
1da177e4 | 987 | err = -EPERM; |
41487c65 | 988 | if (task_session(p) != task_session(group_leader)) |
1da177e4 LT |
989 | goto out; |
990 | err = -EACCES; | |
991 | if (p->did_exec) | |
992 | goto out; | |
993 | } else { | |
994 | err = -ESRCH; | |
ee0acf90 | 995 | if (p != group_leader) |
1da177e4 LT |
996 | goto out; |
997 | } | |
998 | ||
999 | err = -EPERM; | |
1000 | if (p->signal->leader) | |
1001 | goto out; | |
1002 | ||
4e021306 | 1003 | pgrp = task_pid(p); |
1da177e4 | 1004 | if (pgid != pid) { |
b488893a | 1005 | struct task_struct *g; |
1da177e4 | 1006 | |
4e021306 ON |
1007 | pgrp = find_vpid(pgid); |
1008 | g = pid_task(pgrp, PIDTYPE_PGID); | |
41487c65 | 1009 | if (!g || task_session(g) != task_session(group_leader)) |
f020bc46 | 1010 | goto out; |
1da177e4 LT |
1011 | } |
1012 | ||
1da177e4 LT |
1013 | err = security_task_setpgid(p, pgid); |
1014 | if (err) | |
1015 | goto out; | |
1016 | ||
4e021306 | 1017 | if (task_pgrp(p) != pgrp) { |
83beaf3c | 1018 | change_pid(p, PIDTYPE_PGID, pgrp); |
4e021306 | 1019 | set_task_pgrp(p, pid_nr(pgrp)); |
1da177e4 LT |
1020 | } |
1021 | ||
1022 | err = 0; | |
1023 | out: | |
1024 | /* All paths lead to here, thus we are safe. -DaveM */ | |
1025 | write_unlock_irq(&tasklist_lock); | |
1026 | return err; | |
1027 | } | |
1028 | ||
dbf040d9 | 1029 | SYSCALL_DEFINE1(getpgid, pid_t, pid) |
1da177e4 | 1030 | { |
12a3de0a ON |
1031 | struct task_struct *p; |
1032 | struct pid *grp; | |
1033 | int retval; | |
1034 | ||
1035 | rcu_read_lock(); | |
756184b7 | 1036 | if (!pid) |
12a3de0a | 1037 | grp = task_pgrp(current); |
756184b7 | 1038 | else { |
1da177e4 | 1039 | retval = -ESRCH; |
12a3de0a ON |
1040 | p = find_task_by_vpid(pid); |
1041 | if (!p) | |
1042 | goto out; | |
1043 | grp = task_pgrp(p); | |
1044 | if (!grp) | |
1045 | goto out; | |
1046 | ||
1047 | retval = security_task_getpgid(p); | |
1048 | if (retval) | |
1049 | goto out; | |
1da177e4 | 1050 | } |
12a3de0a ON |
1051 | retval = pid_vnr(grp); |
1052 | out: | |
1053 | rcu_read_unlock(); | |
1054 | return retval; | |
1da177e4 LT |
1055 | } |
1056 | ||
1057 | #ifdef __ARCH_WANT_SYS_GETPGRP | |
1058 | ||
dbf040d9 | 1059 | SYSCALL_DEFINE0(getpgrp) |
1da177e4 | 1060 | { |
12a3de0a | 1061 | return sys_getpgid(0); |
1da177e4 LT |
1062 | } |
1063 | ||
1064 | #endif | |
1065 | ||
dbf040d9 | 1066 | SYSCALL_DEFINE1(getsid, pid_t, pid) |
1da177e4 | 1067 | { |
1dd768c0 ON |
1068 | struct task_struct *p; |
1069 | struct pid *sid; | |
1070 | int retval; | |
1071 | ||
1072 | rcu_read_lock(); | |
756184b7 | 1073 | if (!pid) |
1dd768c0 | 1074 | sid = task_session(current); |
756184b7 | 1075 | else { |
1da177e4 | 1076 | retval = -ESRCH; |
1dd768c0 ON |
1077 | p = find_task_by_vpid(pid); |
1078 | if (!p) | |
1079 | goto out; | |
1080 | sid = task_session(p); | |
1081 | if (!sid) | |
1082 | goto out; | |
1083 | ||
1084 | retval = security_task_getsid(p); | |
1085 | if (retval) | |
1086 | goto out; | |
1da177e4 | 1087 | } |
1dd768c0 ON |
1088 | retval = pid_vnr(sid); |
1089 | out: | |
1090 | rcu_read_unlock(); | |
1091 | return retval; | |
1da177e4 LT |
1092 | } |
1093 | ||
b290ebe2 | 1094 | SYSCALL_DEFINE0(setsid) |
1da177e4 | 1095 | { |
e19f247a | 1096 | struct task_struct *group_leader = current->group_leader; |
e4cc0a9c ON |
1097 | struct pid *sid = task_pid(group_leader); |
1098 | pid_t session = pid_vnr(sid); | |
1da177e4 LT |
1099 | int err = -EPERM; |
1100 | ||
1da177e4 | 1101 | write_lock_irq(&tasklist_lock); |
390e2ff0 EB |
1102 | /* Fail if I am already a session leader */ |
1103 | if (group_leader->signal->leader) | |
1104 | goto out; | |
1105 | ||
430c6231 ON |
1106 | /* Fail if a process group id already exists that equals the |
1107 | * proposed session id. | |
390e2ff0 | 1108 | */ |
6806aac6 | 1109 | if (pid_task(sid, PIDTYPE_PGID)) |
1da177e4 LT |
1110 | goto out; |
1111 | ||
e19f247a | 1112 | group_leader->signal->leader = 1; |
8520d7c7 | 1113 | __set_special_pids(sid); |
24ec839c | 1114 | |
9c9f4ded | 1115 | proc_clear_tty(group_leader); |
24ec839c | 1116 | |
e4cc0a9c | 1117 | err = session; |
1da177e4 LT |
1118 | out: |
1119 | write_unlock_irq(&tasklist_lock); | |
1da177e4 LT |
1120 | return err; |
1121 | } | |
1122 | ||
1123 | /* | |
1124 | * Supplementary group IDs | |
1125 | */ | |
1126 | ||
1127 | /* init to 2 - one for init_task, one to ensure it is never freed */ | |
1128 | struct group_info init_groups = { .usage = ATOMIC_INIT(2) }; | |
1129 | ||
1130 | struct group_info *groups_alloc(int gidsetsize) | |
1131 | { | |
1132 | struct group_info *group_info; | |
1133 | int nblocks; | |
1134 | int i; | |
1135 | ||
1136 | nblocks = (gidsetsize + NGROUPS_PER_BLOCK - 1) / NGROUPS_PER_BLOCK; | |
1137 | /* Make sure we always allocate at least one indirect block pointer */ | |
1138 | nblocks = nblocks ? : 1; | |
1139 | group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *), GFP_USER); | |
1140 | if (!group_info) | |
1141 | return NULL; | |
1142 | group_info->ngroups = gidsetsize; | |
1143 | group_info->nblocks = nblocks; | |
1144 | atomic_set(&group_info->usage, 1); | |
1145 | ||
756184b7 | 1146 | if (gidsetsize <= NGROUPS_SMALL) |
1da177e4 | 1147 | group_info->blocks[0] = group_info->small_block; |
756184b7 | 1148 | else { |
1da177e4 LT |
1149 | for (i = 0; i < nblocks; i++) { |
1150 | gid_t *b; | |
1151 | b = (void *)__get_free_page(GFP_USER); | |
1152 | if (!b) | |
1153 | goto out_undo_partial_alloc; | |
1154 | group_info->blocks[i] = b; | |
1155 | } | |
1156 | } | |
1157 | return group_info; | |
1158 | ||
1159 | out_undo_partial_alloc: | |
1160 | while (--i >= 0) { | |
1161 | free_page((unsigned long)group_info->blocks[i]); | |
1162 | } | |
1163 | kfree(group_info); | |
1164 | return NULL; | |
1165 | } | |
1166 | ||
1167 | EXPORT_SYMBOL(groups_alloc); | |
1168 | ||
1169 | void groups_free(struct group_info *group_info) | |
1170 | { | |
1171 | if (group_info->blocks[0] != group_info->small_block) { | |
1172 | int i; | |
1173 | for (i = 0; i < group_info->nblocks; i++) | |
1174 | free_page((unsigned long)group_info->blocks[i]); | |
1175 | } | |
1176 | kfree(group_info); | |
1177 | } | |
1178 | ||
1179 | EXPORT_SYMBOL(groups_free); | |
1180 | ||
1181 | /* export the group_info to a user-space array */ | |
1182 | static int groups_to_user(gid_t __user *grouplist, | |
d84f4f99 | 1183 | const struct group_info *group_info) |
1da177e4 LT |
1184 | { |
1185 | int i; | |
1bf47346 | 1186 | unsigned int count = group_info->ngroups; |
1da177e4 LT |
1187 | |
1188 | for (i = 0; i < group_info->nblocks; i++) { | |
1bf47346 ED |
1189 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
1190 | unsigned int len = cp_count * sizeof(*grouplist); | |
1da177e4 | 1191 | |
1bf47346 | 1192 | if (copy_to_user(grouplist, group_info->blocks[i], len)) |
1da177e4 LT |
1193 | return -EFAULT; |
1194 | ||
1bf47346 | 1195 | grouplist += NGROUPS_PER_BLOCK; |
1da177e4 LT |
1196 | count -= cp_count; |
1197 | } | |
1198 | return 0; | |
1199 | } | |
1200 | ||
1201 | /* fill a group_info from a user-space array - it must be allocated already */ | |
1202 | static int groups_from_user(struct group_info *group_info, | |
1203 | gid_t __user *grouplist) | |
756184b7 | 1204 | { |
1da177e4 | 1205 | int i; |
1bf47346 | 1206 | unsigned int count = group_info->ngroups; |
1da177e4 LT |
1207 | |
1208 | for (i = 0; i < group_info->nblocks; i++) { | |
1bf47346 ED |
1209 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
1210 | unsigned int len = cp_count * sizeof(*grouplist); | |
1da177e4 | 1211 | |
1bf47346 | 1212 | if (copy_from_user(group_info->blocks[i], grouplist, len)) |
1da177e4 LT |
1213 | return -EFAULT; |
1214 | ||
1bf47346 | 1215 | grouplist += NGROUPS_PER_BLOCK; |
1da177e4 LT |
1216 | count -= cp_count; |
1217 | } | |
1218 | return 0; | |
1219 | } | |
1220 | ||
ebe8b541 | 1221 | /* a simple Shell sort */ |
1da177e4 LT |
1222 | static void groups_sort(struct group_info *group_info) |
1223 | { | |
1224 | int base, max, stride; | |
1225 | int gidsetsize = group_info->ngroups; | |
1226 | ||
1227 | for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1) | |
1228 | ; /* nothing */ | |
1229 | stride /= 3; | |
1230 | ||
1231 | while (stride) { | |
1232 | max = gidsetsize - stride; | |
1233 | for (base = 0; base < max; base++) { | |
1234 | int left = base; | |
1235 | int right = left + stride; | |
1236 | gid_t tmp = GROUP_AT(group_info, right); | |
1237 | ||
1238 | while (left >= 0 && GROUP_AT(group_info, left) > tmp) { | |
1239 | GROUP_AT(group_info, right) = | |
1240 | GROUP_AT(group_info, left); | |
1241 | right = left; | |
1242 | left -= stride; | |
1243 | } | |
1244 | GROUP_AT(group_info, right) = tmp; | |
1245 | } | |
1246 | stride /= 3; | |
1247 | } | |
1248 | } | |
1249 | ||
1250 | /* a simple bsearch */ | |
86a264ab | 1251 | int groups_search(const struct group_info *group_info, gid_t grp) |
1da177e4 | 1252 | { |
d74beb9f | 1253 | unsigned int left, right; |
1da177e4 LT |
1254 | |
1255 | if (!group_info) | |
1256 | return 0; | |
1257 | ||
1258 | left = 0; | |
1259 | right = group_info->ngroups; | |
1260 | while (left < right) { | |
d74beb9f | 1261 | unsigned int mid = (left+right)/2; |
1da177e4 LT |
1262 | int cmp = grp - GROUP_AT(group_info, mid); |
1263 | if (cmp > 0) | |
1264 | left = mid + 1; | |
1265 | else if (cmp < 0) | |
1266 | right = mid; | |
1267 | else | |
1268 | return 1; | |
1269 | } | |
1270 | return 0; | |
1271 | } | |
1272 | ||
b6dff3ec | 1273 | /** |
d84f4f99 DH |
1274 | * set_groups - Change a group subscription in a set of credentials |
1275 | * @new: The newly prepared set of credentials to alter | |
1276 | * @group_info: The group list to install | |
b6dff3ec | 1277 | * |
d84f4f99 DH |
1278 | * Validate a group subscription and, if valid, insert it into a set |
1279 | * of credentials. | |
b6dff3ec | 1280 | */ |
d84f4f99 | 1281 | int set_groups(struct cred *new, struct group_info *group_info) |
1da177e4 LT |
1282 | { |
1283 | int retval; | |
1da177e4 LT |
1284 | |
1285 | retval = security_task_setgroups(group_info); | |
1286 | if (retval) | |
1287 | return retval; | |
1288 | ||
d84f4f99 | 1289 | put_group_info(new->group_info); |
1da177e4 LT |
1290 | groups_sort(group_info); |
1291 | get_group_info(group_info); | |
d84f4f99 | 1292 | new->group_info = group_info; |
1da177e4 LT |
1293 | return 0; |
1294 | } | |
1295 | ||
b6dff3ec DH |
1296 | EXPORT_SYMBOL(set_groups); |
1297 | ||
1298 | /** | |
1299 | * set_current_groups - Change current's group subscription | |
1300 | * @group_info: The group list to impose | |
1301 | * | |
1302 | * Validate a group subscription and, if valid, impose it upon current's task | |
1303 | * security record. | |
1304 | */ | |
1305 | int set_current_groups(struct group_info *group_info) | |
1306 | { | |
d84f4f99 DH |
1307 | struct cred *new; |
1308 | int ret; | |
1309 | ||
1310 | new = prepare_creds(); | |
1311 | if (!new) | |
1312 | return -ENOMEM; | |
1313 | ||
1314 | ret = set_groups(new, group_info); | |
1315 | if (ret < 0) { | |
1316 | abort_creds(new); | |
1317 | return ret; | |
1318 | } | |
1319 | ||
1320 | return commit_creds(new); | |
b6dff3ec DH |
1321 | } |
1322 | ||
1da177e4 LT |
1323 | EXPORT_SYMBOL(set_current_groups); |
1324 | ||
ae1251ab | 1325 | SYSCALL_DEFINE2(getgroups, int, gidsetsize, gid_t __user *, grouplist) |
1da177e4 | 1326 | { |
86a264ab DH |
1327 | const struct cred *cred = current_cred(); |
1328 | int i; | |
1da177e4 LT |
1329 | |
1330 | if (gidsetsize < 0) | |
1331 | return -EINVAL; | |
1332 | ||
1333 | /* no need to grab task_lock here; it cannot change */ | |
b6dff3ec | 1334 | i = cred->group_info->ngroups; |
1da177e4 LT |
1335 | if (gidsetsize) { |
1336 | if (i > gidsetsize) { | |
1337 | i = -EINVAL; | |
1338 | goto out; | |
1339 | } | |
b6dff3ec | 1340 | if (groups_to_user(grouplist, cred->group_info)) { |
1da177e4 LT |
1341 | i = -EFAULT; |
1342 | goto out; | |
1343 | } | |
1344 | } | |
1345 | out: | |
1da177e4 LT |
1346 | return i; |
1347 | } | |
1348 | ||
1349 | /* | |
1350 | * SMP: Our groups are copy-on-write. We can set them safely | |
1351 | * without another task interfering. | |
1352 | */ | |
1353 | ||
b290ebe2 | 1354 | SYSCALL_DEFINE2(setgroups, int, gidsetsize, gid_t __user *, grouplist) |
1da177e4 LT |
1355 | { |
1356 | struct group_info *group_info; | |
1357 | int retval; | |
1358 | ||
1359 | if (!capable(CAP_SETGID)) | |
1360 | return -EPERM; | |
1361 | if ((unsigned)gidsetsize > NGROUPS_MAX) | |
1362 | return -EINVAL; | |
1363 | ||
1364 | group_info = groups_alloc(gidsetsize); | |
1365 | if (!group_info) | |
1366 | return -ENOMEM; | |
1367 | retval = groups_from_user(group_info, grouplist); | |
1368 | if (retval) { | |
1369 | put_group_info(group_info); | |
1370 | return retval; | |
1371 | } | |
1372 | ||
1373 | retval = set_current_groups(group_info); | |
1374 | put_group_info(group_info); | |
1375 | ||
1376 | return retval; | |
1377 | } | |
1378 | ||
1379 | /* | |
1380 | * Check whether we're fsgid/egid or in the supplemental group.. | |
1381 | */ | |
1382 | int in_group_p(gid_t grp) | |
1383 | { | |
86a264ab | 1384 | const struct cred *cred = current_cred(); |
1da177e4 | 1385 | int retval = 1; |
86a264ab | 1386 | |
b6dff3ec DH |
1387 | if (grp != cred->fsgid) |
1388 | retval = groups_search(cred->group_info, grp); | |
1da177e4 LT |
1389 | return retval; |
1390 | } | |
1391 | ||
1392 | EXPORT_SYMBOL(in_group_p); | |
1393 | ||
1394 | int in_egroup_p(gid_t grp) | |
1395 | { | |
86a264ab | 1396 | const struct cred *cred = current_cred(); |
1da177e4 | 1397 | int retval = 1; |
86a264ab | 1398 | |
b6dff3ec DH |
1399 | if (grp != cred->egid) |
1400 | retval = groups_search(cred->group_info, grp); | |
1da177e4 LT |
1401 | return retval; |
1402 | } | |
1403 | ||
1404 | EXPORT_SYMBOL(in_egroup_p); | |
1405 | ||
1406 | DECLARE_RWSEM(uts_sem); | |
1407 | ||
e48fbb69 | 1408 | SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name) |
1da177e4 LT |
1409 | { |
1410 | int errno = 0; | |
1411 | ||
1412 | down_read(&uts_sem); | |
e9ff3990 | 1413 | if (copy_to_user(name, utsname(), sizeof *name)) |
1da177e4 LT |
1414 | errno = -EFAULT; |
1415 | up_read(&uts_sem); | |
1416 | return errno; | |
1417 | } | |
1418 | ||
5a8a82b1 | 1419 | SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) |
1da177e4 LT |
1420 | { |
1421 | int errno; | |
1422 | char tmp[__NEW_UTS_LEN]; | |
1423 | ||
1424 | if (!capable(CAP_SYS_ADMIN)) | |
1425 | return -EPERM; | |
1426 | if (len < 0 || len > __NEW_UTS_LEN) | |
1427 | return -EINVAL; | |
1428 | down_write(&uts_sem); | |
1429 | errno = -EFAULT; | |
1430 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1431 | struct new_utsname *u = utsname(); |
1432 | ||
1433 | memcpy(u->nodename, tmp, len); | |
1434 | memset(u->nodename + len, 0, sizeof(u->nodename) - len); | |
1da177e4 LT |
1435 | errno = 0; |
1436 | } | |
1437 | up_write(&uts_sem); | |
1438 | return errno; | |
1439 | } | |
1440 | ||
1441 | #ifdef __ARCH_WANT_SYS_GETHOSTNAME | |
1442 | ||
5a8a82b1 | 1443 | SYSCALL_DEFINE2(gethostname, char __user *, name, int, len) |
1da177e4 LT |
1444 | { |
1445 | int i, errno; | |
9679e4dd | 1446 | struct new_utsname *u; |
1da177e4 LT |
1447 | |
1448 | if (len < 0) | |
1449 | return -EINVAL; | |
1450 | down_read(&uts_sem); | |
9679e4dd AM |
1451 | u = utsname(); |
1452 | i = 1 + strlen(u->nodename); | |
1da177e4 LT |
1453 | if (i > len) |
1454 | i = len; | |
1455 | errno = 0; | |
9679e4dd | 1456 | if (copy_to_user(name, u->nodename, i)) |
1da177e4 LT |
1457 | errno = -EFAULT; |
1458 | up_read(&uts_sem); | |
1459 | return errno; | |
1460 | } | |
1461 | ||
1462 | #endif | |
1463 | ||
1464 | /* | |
1465 | * Only setdomainname; getdomainname can be implemented by calling | |
1466 | * uname() | |
1467 | */ | |
5a8a82b1 | 1468 | SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) |
1da177e4 LT |
1469 | { |
1470 | int errno; | |
1471 | char tmp[__NEW_UTS_LEN]; | |
1472 | ||
1473 | if (!capable(CAP_SYS_ADMIN)) | |
1474 | return -EPERM; | |
1475 | if (len < 0 || len > __NEW_UTS_LEN) | |
1476 | return -EINVAL; | |
1477 | ||
1478 | down_write(&uts_sem); | |
1479 | errno = -EFAULT; | |
1480 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1481 | struct new_utsname *u = utsname(); |
1482 | ||
1483 | memcpy(u->domainname, tmp, len); | |
1484 | memset(u->domainname + len, 0, sizeof(u->domainname) - len); | |
1da177e4 LT |
1485 | errno = 0; |
1486 | } | |
1487 | up_write(&uts_sem); | |
1488 | return errno; | |
1489 | } | |
1490 | ||
e48fbb69 | 1491 | SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1da177e4 LT |
1492 | { |
1493 | if (resource >= RLIM_NLIMITS) | |
1494 | return -EINVAL; | |
1495 | else { | |
1496 | struct rlimit value; | |
1497 | task_lock(current->group_leader); | |
1498 | value = current->signal->rlim[resource]; | |
1499 | task_unlock(current->group_leader); | |
1500 | return copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; | |
1501 | } | |
1502 | } | |
1503 | ||
1504 | #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT | |
1505 | ||
1506 | /* | |
1507 | * Back compatibility for getrlimit. Needed for some apps. | |
1508 | */ | |
1509 | ||
e48fbb69 HC |
1510 | SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, |
1511 | struct rlimit __user *, rlim) | |
1da177e4 LT |
1512 | { |
1513 | struct rlimit x; | |
1514 | if (resource >= RLIM_NLIMITS) | |
1515 | return -EINVAL; | |
1516 | ||
1517 | task_lock(current->group_leader); | |
1518 | x = current->signal->rlim[resource]; | |
1519 | task_unlock(current->group_leader); | |
756184b7 | 1520 | if (x.rlim_cur > 0x7FFFFFFF) |
1da177e4 | 1521 | x.rlim_cur = 0x7FFFFFFF; |
756184b7 | 1522 | if (x.rlim_max > 0x7FFFFFFF) |
1da177e4 LT |
1523 | x.rlim_max = 0x7FFFFFFF; |
1524 | return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0; | |
1525 | } | |
1526 | ||
1527 | #endif | |
1528 | ||
e48fbb69 | 1529 | SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1da177e4 LT |
1530 | { |
1531 | struct rlimit new_rlim, *old_rlim; | |
1532 | int retval; | |
1533 | ||
1534 | if (resource >= RLIM_NLIMITS) | |
1535 | return -EINVAL; | |
ec9e16ba | 1536 | if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) |
1da177e4 | 1537 | return -EFAULT; |
60fd760f AM |
1538 | if (new_rlim.rlim_cur > new_rlim.rlim_max) |
1539 | return -EINVAL; | |
1da177e4 LT |
1540 | old_rlim = current->signal->rlim + resource; |
1541 | if ((new_rlim.rlim_max > old_rlim->rlim_max) && | |
1542 | !capable(CAP_SYS_RESOURCE)) | |
1543 | return -EPERM; | |
60fd760f AM |
1544 | if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open) |
1545 | return -EPERM; | |
1da177e4 LT |
1546 | |
1547 | retval = security_task_setrlimit(resource, &new_rlim); | |
1548 | if (retval) | |
1549 | return retval; | |
1550 | ||
9926e4c7 TA |
1551 | if (resource == RLIMIT_CPU && new_rlim.rlim_cur == 0) { |
1552 | /* | |
1553 | * The caller is asking for an immediate RLIMIT_CPU | |
1554 | * expiry. But we use the zero value to mean "it was | |
1555 | * never set". So let's cheat and make it one second | |
1556 | * instead | |
1557 | */ | |
1558 | new_rlim.rlim_cur = 1; | |
1559 | } | |
1560 | ||
1da177e4 LT |
1561 | task_lock(current->group_leader); |
1562 | *old_rlim = new_rlim; | |
1563 | task_unlock(current->group_leader); | |
1564 | ||
ec9e16ba AM |
1565 | if (resource != RLIMIT_CPU) |
1566 | goto out; | |
d3561f78 AM |
1567 | |
1568 | /* | |
1569 | * RLIMIT_CPU handling. Note that the kernel fails to return an error | |
1570 | * code if it rejected the user's attempt to set RLIMIT_CPU. This is a | |
1571 | * very long-standing error, and fixing it now risks breakage of | |
1572 | * applications, so we live with it | |
1573 | */ | |
ec9e16ba AM |
1574 | if (new_rlim.rlim_cur == RLIM_INFINITY) |
1575 | goto out; | |
1576 | ||
f06febc9 | 1577 | update_rlimit_cpu(new_rlim.rlim_cur); |
ec9e16ba | 1578 | out: |
1da177e4 LT |
1579 | return 0; |
1580 | } | |
1581 | ||
1582 | /* | |
1583 | * It would make sense to put struct rusage in the task_struct, | |
1584 | * except that would make the task_struct be *really big*. After | |
1585 | * task_struct gets moved into malloc'ed memory, it would | |
1586 | * make sense to do this. It will make moving the rest of the information | |
1587 | * a lot simpler! (Which we're not doing right now because we're not | |
1588 | * measuring them yet). | |
1589 | * | |
1da177e4 LT |
1590 | * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
1591 | * races with threads incrementing their own counters. But since word | |
1592 | * reads are atomic, we either get new values or old values and we don't | |
1593 | * care which for the sums. We always take the siglock to protect reading | |
1594 | * the c* fields from p->signal from races with exit.c updating those | |
1595 | * fields when reaping, so a sample either gets all the additions of a | |
1596 | * given child after it's reaped, or none so this sample is before reaping. | |
2dd0ebcd | 1597 | * |
de047c1b RT |
1598 | * Locking: |
1599 | * We need to take the siglock for CHILDEREN, SELF and BOTH | |
1600 | * for the cases current multithreaded, non-current single threaded | |
1601 | * non-current multithreaded. Thread traversal is now safe with | |
1602 | * the siglock held. | |
1603 | * Strictly speaking, we donot need to take the siglock if we are current and | |
1604 | * single threaded, as no one else can take our signal_struct away, no one | |
1605 | * else can reap the children to update signal->c* counters, and no one else | |
1606 | * can race with the signal-> fields. If we do not take any lock, the | |
1607 | * signal-> fields could be read out of order while another thread was just | |
1608 | * exiting. So we should place a read memory barrier when we avoid the lock. | |
1609 | * On the writer side, write memory barrier is implied in __exit_signal | |
1610 | * as __exit_signal releases the siglock spinlock after updating the signal-> | |
1611 | * fields. But we don't do this yet to keep things simple. | |
2dd0ebcd | 1612 | * |
1da177e4 LT |
1613 | */ |
1614 | ||
f06febc9 | 1615 | static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) |
679c9cd4 | 1616 | { |
679c9cd4 SK |
1617 | r->ru_nvcsw += t->nvcsw; |
1618 | r->ru_nivcsw += t->nivcsw; | |
1619 | r->ru_minflt += t->min_flt; | |
1620 | r->ru_majflt += t->maj_flt; | |
1621 | r->ru_inblock += task_io_get_inblock(t); | |
1622 | r->ru_oublock += task_io_get_oublock(t); | |
1623 | } | |
1624 | ||
1da177e4 LT |
1625 | static void k_getrusage(struct task_struct *p, int who, struct rusage *r) |
1626 | { | |
1627 | struct task_struct *t; | |
1628 | unsigned long flags; | |
1629 | cputime_t utime, stime; | |
f06febc9 | 1630 | struct task_cputime cputime; |
1da177e4 LT |
1631 | |
1632 | memset((char *) r, 0, sizeof *r); | |
2dd0ebcd | 1633 | utime = stime = cputime_zero; |
1da177e4 | 1634 | |
679c9cd4 | 1635 | if (who == RUSAGE_THREAD) { |
8916edef KM |
1636 | utime = task_utime(current); |
1637 | stime = task_stime(current); | |
f06febc9 | 1638 | accumulate_thread_rusage(p, r); |
679c9cd4 SK |
1639 | goto out; |
1640 | } | |
1641 | ||
d6cf723a | 1642 | if (!lock_task_sighand(p, &flags)) |
de047c1b | 1643 | return; |
0f59cc4a | 1644 | |
1da177e4 | 1645 | switch (who) { |
0f59cc4a | 1646 | case RUSAGE_BOTH: |
1da177e4 | 1647 | case RUSAGE_CHILDREN: |
1da177e4 LT |
1648 | utime = p->signal->cutime; |
1649 | stime = p->signal->cstime; | |
1650 | r->ru_nvcsw = p->signal->cnvcsw; | |
1651 | r->ru_nivcsw = p->signal->cnivcsw; | |
1652 | r->ru_minflt = p->signal->cmin_flt; | |
1653 | r->ru_majflt = p->signal->cmaj_flt; | |
6eaeeaba ED |
1654 | r->ru_inblock = p->signal->cinblock; |
1655 | r->ru_oublock = p->signal->coublock; | |
0f59cc4a ON |
1656 | |
1657 | if (who == RUSAGE_CHILDREN) | |
1658 | break; | |
1659 | ||
1da177e4 | 1660 | case RUSAGE_SELF: |
f06febc9 FM |
1661 | thread_group_cputime(p, &cputime); |
1662 | utime = cputime_add(utime, cputime.utime); | |
1663 | stime = cputime_add(stime, cputime.stime); | |
1da177e4 LT |
1664 | r->ru_nvcsw += p->signal->nvcsw; |
1665 | r->ru_nivcsw += p->signal->nivcsw; | |
1666 | r->ru_minflt += p->signal->min_flt; | |
1667 | r->ru_majflt += p->signal->maj_flt; | |
6eaeeaba ED |
1668 | r->ru_inblock += p->signal->inblock; |
1669 | r->ru_oublock += p->signal->oublock; | |
1da177e4 LT |
1670 | t = p; |
1671 | do { | |
f06febc9 | 1672 | accumulate_thread_rusage(t, r); |
1da177e4 LT |
1673 | t = next_thread(t); |
1674 | } while (t != p); | |
1da177e4 | 1675 | break; |
0f59cc4a | 1676 | |
1da177e4 LT |
1677 | default: |
1678 | BUG(); | |
1679 | } | |
de047c1b | 1680 | unlock_task_sighand(p, &flags); |
de047c1b | 1681 | |
679c9cd4 | 1682 | out: |
0f59cc4a ON |
1683 | cputime_to_timeval(utime, &r->ru_utime); |
1684 | cputime_to_timeval(stime, &r->ru_stime); | |
1da177e4 LT |
1685 | } |
1686 | ||
1687 | int getrusage(struct task_struct *p, int who, struct rusage __user *ru) | |
1688 | { | |
1689 | struct rusage r; | |
1da177e4 | 1690 | k_getrusage(p, who, &r); |
1da177e4 LT |
1691 | return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
1692 | } | |
1693 | ||
e48fbb69 | 1694 | SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) |
1da177e4 | 1695 | { |
679c9cd4 SK |
1696 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
1697 | who != RUSAGE_THREAD) | |
1da177e4 LT |
1698 | return -EINVAL; |
1699 | return getrusage(current, who, ru); | |
1700 | } | |
1701 | ||
e48fbb69 | 1702 | SYSCALL_DEFINE1(umask, int, mask) |
1da177e4 LT |
1703 | { |
1704 | mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); | |
1705 | return mask; | |
1706 | } | |
3b7391de | 1707 | |
c4ea37c2 HC |
1708 | SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, |
1709 | unsigned long, arg4, unsigned long, arg5) | |
1da177e4 | 1710 | { |
b6dff3ec DH |
1711 | struct task_struct *me = current; |
1712 | unsigned char comm[sizeof(me->comm)]; | |
1713 | long error; | |
1da177e4 | 1714 | |
d84f4f99 DH |
1715 | error = security_task_prctl(option, arg2, arg3, arg4, arg5); |
1716 | if (error != -ENOSYS) | |
1da177e4 LT |
1717 | return error; |
1718 | ||
d84f4f99 | 1719 | error = 0; |
1da177e4 LT |
1720 | switch (option) { |
1721 | case PR_SET_PDEATHSIG: | |
0730ded5 | 1722 | if (!valid_signal(arg2)) { |
1da177e4 LT |
1723 | error = -EINVAL; |
1724 | break; | |
1725 | } | |
b6dff3ec DH |
1726 | me->pdeath_signal = arg2; |
1727 | error = 0; | |
1da177e4 LT |
1728 | break; |
1729 | case PR_GET_PDEATHSIG: | |
b6dff3ec | 1730 | error = put_user(me->pdeath_signal, (int __user *)arg2); |
1da177e4 LT |
1731 | break; |
1732 | case PR_GET_DUMPABLE: | |
b6dff3ec | 1733 | error = get_dumpable(me->mm); |
1da177e4 LT |
1734 | break; |
1735 | case PR_SET_DUMPABLE: | |
abf75a50 | 1736 | if (arg2 < 0 || arg2 > 1) { |
1da177e4 LT |
1737 | error = -EINVAL; |
1738 | break; | |
1739 | } | |
b6dff3ec DH |
1740 | set_dumpable(me->mm, arg2); |
1741 | error = 0; | |
1da177e4 LT |
1742 | break; |
1743 | ||
1744 | case PR_SET_UNALIGN: | |
b6dff3ec | 1745 | error = SET_UNALIGN_CTL(me, arg2); |
1da177e4 LT |
1746 | break; |
1747 | case PR_GET_UNALIGN: | |
b6dff3ec | 1748 | error = GET_UNALIGN_CTL(me, arg2); |
1da177e4 LT |
1749 | break; |
1750 | case PR_SET_FPEMU: | |
b6dff3ec | 1751 | error = SET_FPEMU_CTL(me, arg2); |
1da177e4 LT |
1752 | break; |
1753 | case PR_GET_FPEMU: | |
b6dff3ec | 1754 | error = GET_FPEMU_CTL(me, arg2); |
1da177e4 LT |
1755 | break; |
1756 | case PR_SET_FPEXC: | |
b6dff3ec | 1757 | error = SET_FPEXC_CTL(me, arg2); |
1da177e4 LT |
1758 | break; |
1759 | case PR_GET_FPEXC: | |
b6dff3ec | 1760 | error = GET_FPEXC_CTL(me, arg2); |
1da177e4 LT |
1761 | break; |
1762 | case PR_GET_TIMING: | |
1763 | error = PR_TIMING_STATISTICAL; | |
1764 | break; | |
1765 | case PR_SET_TIMING: | |
7b26655f | 1766 | if (arg2 != PR_TIMING_STATISTICAL) |
1da177e4 | 1767 | error = -EINVAL; |
b6dff3ec DH |
1768 | else |
1769 | error = 0; | |
1da177e4 LT |
1770 | break; |
1771 | ||
b6dff3ec DH |
1772 | case PR_SET_NAME: |
1773 | comm[sizeof(me->comm)-1] = 0; | |
1774 | if (strncpy_from_user(comm, (char __user *)arg2, | |
1775 | sizeof(me->comm) - 1) < 0) | |
1da177e4 | 1776 | return -EFAULT; |
b6dff3ec | 1777 | set_task_comm(me, comm); |
1da177e4 | 1778 | return 0; |
b6dff3ec DH |
1779 | case PR_GET_NAME: |
1780 | get_task_comm(comm, me); | |
1781 | if (copy_to_user((char __user *)arg2, comm, | |
1782 | sizeof(comm))) | |
1da177e4 LT |
1783 | return -EFAULT; |
1784 | return 0; | |
651d765d | 1785 | case PR_GET_ENDIAN: |
b6dff3ec | 1786 | error = GET_ENDIAN(me, arg2); |
651d765d AB |
1787 | break; |
1788 | case PR_SET_ENDIAN: | |
b6dff3ec | 1789 | error = SET_ENDIAN(me, arg2); |
651d765d AB |
1790 | break; |
1791 | ||
1d9d02fe AA |
1792 | case PR_GET_SECCOMP: |
1793 | error = prctl_get_seccomp(); | |
1794 | break; | |
1795 | case PR_SET_SECCOMP: | |
1796 | error = prctl_set_seccomp(arg2); | |
1797 | break; | |
8fb402bc EB |
1798 | case PR_GET_TSC: |
1799 | error = GET_TSC_CTL(arg2); | |
1800 | break; | |
1801 | case PR_SET_TSC: | |
1802 | error = SET_TSC_CTL(arg2); | |
1803 | break; | |
6976675d AV |
1804 | case PR_GET_TIMERSLACK: |
1805 | error = current->timer_slack_ns; | |
1806 | break; | |
1807 | case PR_SET_TIMERSLACK: | |
1808 | if (arg2 <= 0) | |
1809 | current->timer_slack_ns = | |
1810 | current->default_timer_slack_ns; | |
1811 | else | |
1812 | current->timer_slack_ns = arg2; | |
b6dff3ec | 1813 | error = 0; |
6976675d | 1814 | break; |
1da177e4 LT |
1815 | default: |
1816 | error = -EINVAL; | |
1817 | break; | |
1818 | } | |
1819 | return error; | |
1820 | } | |
3cfc348b | 1821 | |
836f92ad HC |
1822 | SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep, |
1823 | struct getcpu_cache __user *, unused) | |
3cfc348b AK |
1824 | { |
1825 | int err = 0; | |
1826 | int cpu = raw_smp_processor_id(); | |
1827 | if (cpup) | |
1828 | err |= put_user(cpu, cpup); | |
1829 | if (nodep) | |
1830 | err |= put_user(cpu_to_node(cpu), nodep); | |
3cfc348b AK |
1831 | return err ? -EFAULT : 0; |
1832 | } | |
10a0a8d4 JF |
1833 | |
1834 | char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff"; | |
1835 | ||
1836 | static void argv_cleanup(char **argv, char **envp) | |
1837 | { | |
1838 | argv_free(argv); | |
1839 | } | |
1840 | ||
1841 | /** | |
1842 | * orderly_poweroff - Trigger an orderly system poweroff | |
1843 | * @force: force poweroff if command execution fails | |
1844 | * | |
1845 | * This may be called from any context to trigger a system shutdown. | |
1846 | * If the orderly shutdown fails, it will force an immediate shutdown. | |
1847 | */ | |
1848 | int orderly_poweroff(bool force) | |
1849 | { | |
1850 | int argc; | |
1851 | char **argv = argv_split(GFP_ATOMIC, poweroff_cmd, &argc); | |
1852 | static char *envp[] = { | |
1853 | "HOME=/", | |
1854 | "PATH=/sbin:/bin:/usr/sbin:/usr/bin", | |
1855 | NULL | |
1856 | }; | |
1857 | int ret = -ENOMEM; | |
1858 | struct subprocess_info *info; | |
1859 | ||
1860 | if (argv == NULL) { | |
1861 | printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n", | |
1862 | __func__, poweroff_cmd); | |
1863 | goto out; | |
1864 | } | |
1865 | ||
ac331d15 | 1866 | info = call_usermodehelper_setup(argv[0], argv, envp, GFP_ATOMIC); |
10a0a8d4 JF |
1867 | if (info == NULL) { |
1868 | argv_free(argv); | |
1869 | goto out; | |
1870 | } | |
1871 | ||
1872 | call_usermodehelper_setcleanup(info, argv_cleanup); | |
1873 | ||
86313c48 | 1874 | ret = call_usermodehelper_exec(info, UMH_NO_WAIT); |
10a0a8d4 JF |
1875 | |
1876 | out: | |
1877 | if (ret && force) { | |
1878 | printk(KERN_WARNING "Failed to start orderly shutdown: " | |
1879 | "forcing the issue\n"); | |
1880 | ||
1881 | /* I guess this should try to kick off some daemon to | |
1882 | sync and poweroff asap. Or not even bother syncing | |
1883 | if we're doing an emergency shutdown? */ | |
1884 | emergency_sync(); | |
1885 | kernel_power_off(); | |
1886 | } | |
1887 | ||
1888 | return ret; | |
1889 | } | |
1890 | EXPORT_SYMBOL_GPL(orderly_poweroff); |