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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> |
1da177e4 LT |
37 | |
38 | #include <linux/compat.h> | |
39 | #include <linux/syscalls.h> | |
00d7c05a | 40 | #include <linux/kprobes.h> |
acce292c | 41 | #include <linux/user_namespace.h> |
1da177e4 LT |
42 | |
43 | #include <asm/uaccess.h> | |
44 | #include <asm/io.h> | |
45 | #include <asm/unistd.h> | |
46 | ||
47 | #ifndef SET_UNALIGN_CTL | |
48 | # define SET_UNALIGN_CTL(a,b) (-EINVAL) | |
49 | #endif | |
50 | #ifndef GET_UNALIGN_CTL | |
51 | # define GET_UNALIGN_CTL(a,b) (-EINVAL) | |
52 | #endif | |
53 | #ifndef SET_FPEMU_CTL | |
54 | # define SET_FPEMU_CTL(a,b) (-EINVAL) | |
55 | #endif | |
56 | #ifndef GET_FPEMU_CTL | |
57 | # define GET_FPEMU_CTL(a,b) (-EINVAL) | |
58 | #endif | |
59 | #ifndef SET_FPEXC_CTL | |
60 | # define SET_FPEXC_CTL(a,b) (-EINVAL) | |
61 | #endif | |
62 | #ifndef GET_FPEXC_CTL | |
63 | # define GET_FPEXC_CTL(a,b) (-EINVAL) | |
64 | #endif | |
651d765d AB |
65 | #ifndef GET_ENDIAN |
66 | # define GET_ENDIAN(a,b) (-EINVAL) | |
67 | #endif | |
68 | #ifndef SET_ENDIAN | |
69 | # define SET_ENDIAN(a,b) (-EINVAL) | |
70 | #endif | |
8fb402bc EB |
71 | #ifndef GET_TSC_CTL |
72 | # define GET_TSC_CTL(a) (-EINVAL) | |
73 | #endif | |
74 | #ifndef SET_TSC_CTL | |
75 | # define SET_TSC_CTL(a) (-EINVAL) | |
76 | #endif | |
1da177e4 LT |
77 | |
78 | /* | |
79 | * this is where the system-wide overflow UID and GID are defined, for | |
80 | * architectures that now have 32-bit UID/GID but didn't in the past | |
81 | */ | |
82 | ||
83 | int overflowuid = DEFAULT_OVERFLOWUID; | |
84 | int overflowgid = DEFAULT_OVERFLOWGID; | |
85 | ||
86 | #ifdef CONFIG_UID16 | |
87 | EXPORT_SYMBOL(overflowuid); | |
88 | EXPORT_SYMBOL(overflowgid); | |
89 | #endif | |
90 | ||
91 | /* | |
92 | * the same as above, but for filesystems which can only store a 16-bit | |
93 | * UID and GID. as such, this is needed on all architectures | |
94 | */ | |
95 | ||
96 | int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; | |
97 | int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; | |
98 | ||
99 | EXPORT_SYMBOL(fs_overflowuid); | |
100 | EXPORT_SYMBOL(fs_overflowgid); | |
101 | ||
102 | /* | |
103 | * this indicates whether you can reboot with ctrl-alt-del: the default is yes | |
104 | */ | |
105 | ||
106 | int C_A_D = 1; | |
9ec52099 CLG |
107 | struct pid *cad_pid; |
108 | EXPORT_SYMBOL(cad_pid); | |
1da177e4 | 109 | |
bd804eba RW |
110 | /* |
111 | * If set, this is used for preparing the system to power off. | |
112 | */ | |
113 | ||
114 | void (*pm_power_off_prepare)(void); | |
bd804eba | 115 | |
c69e8d9c DH |
116 | /* |
117 | * set the priority of a task | |
118 | * - the caller must hold the RCU read lock | |
119 | */ | |
1da177e4 LT |
120 | static int set_one_prio(struct task_struct *p, int niceval, int error) |
121 | { | |
c69e8d9c | 122 | const struct cred *cred = current_cred(), *pcred = __task_cred(p); |
1da177e4 LT |
123 | int no_nice; |
124 | ||
c69e8d9c DH |
125 | if (pcred->uid != cred->euid && |
126 | pcred->euid != cred->euid && !capable(CAP_SYS_NICE)) { | |
1da177e4 LT |
127 | error = -EPERM; |
128 | goto out; | |
129 | } | |
e43379f1 | 130 | if (niceval < task_nice(p) && !can_nice(p, niceval)) { |
1da177e4 LT |
131 | error = -EACCES; |
132 | goto out; | |
133 | } | |
134 | no_nice = security_task_setnice(p, niceval); | |
135 | if (no_nice) { | |
136 | error = no_nice; | |
137 | goto out; | |
138 | } | |
139 | if (error == -ESRCH) | |
140 | error = 0; | |
141 | set_user_nice(p, niceval); | |
142 | out: | |
143 | return error; | |
144 | } | |
145 | ||
754fe8d2 | 146 | SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval) |
1da177e4 LT |
147 | { |
148 | struct task_struct *g, *p; | |
149 | struct user_struct *user; | |
86a264ab | 150 | const struct cred *cred = current_cred(); |
1da177e4 | 151 | int error = -EINVAL; |
41487c65 | 152 | struct pid *pgrp; |
1da177e4 | 153 | |
3e88c553 | 154 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
155 | goto out; |
156 | ||
157 | /* normalize: avoid signed division (rounding problems) */ | |
158 | error = -ESRCH; | |
159 | if (niceval < -20) | |
160 | niceval = -20; | |
161 | if (niceval > 19) | |
162 | niceval = 19; | |
163 | ||
164 | read_lock(&tasklist_lock); | |
165 | switch (which) { | |
166 | case PRIO_PROCESS: | |
41487c65 | 167 | if (who) |
228ebcbe | 168 | p = find_task_by_vpid(who); |
41487c65 EB |
169 | else |
170 | p = current; | |
1da177e4 LT |
171 | if (p) |
172 | error = set_one_prio(p, niceval, error); | |
173 | break; | |
174 | case PRIO_PGRP: | |
41487c65 | 175 | if (who) |
b488893a | 176 | pgrp = find_vpid(who); |
41487c65 EB |
177 | else |
178 | pgrp = task_pgrp(current); | |
2d70b68d | 179 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 | 180 | error = set_one_prio(p, niceval, error); |
2d70b68d | 181 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
182 | break; |
183 | case PRIO_USER: | |
d84f4f99 | 184 | user = (struct user_struct *) cred->user; |
1da177e4 | 185 | if (!who) |
86a264ab DH |
186 | who = cred->uid; |
187 | else if ((who != cred->uid) && | |
188 | !(user = find_user(who))) | |
189 | goto out_unlock; /* No processes for this user */ | |
1da177e4 LT |
190 | |
191 | do_each_thread(g, p) | |
86a264ab | 192 | if (__task_cred(p)->uid == who) |
1da177e4 LT |
193 | error = set_one_prio(p, niceval, error); |
194 | while_each_thread(g, p); | |
86a264ab | 195 | if (who != cred->uid) |
1da177e4 LT |
196 | free_uid(user); /* For find_user() */ |
197 | break; | |
198 | } | |
199 | out_unlock: | |
200 | read_unlock(&tasklist_lock); | |
201 | out: | |
202 | return error; | |
203 | } | |
204 | ||
205 | /* | |
206 | * Ugh. To avoid negative return values, "getpriority()" will | |
207 | * not return the normal nice-value, but a negated value that | |
208 | * has been offset by 20 (ie it returns 40..1 instead of -20..19) | |
209 | * to stay compatible. | |
210 | */ | |
754fe8d2 | 211 | SYSCALL_DEFINE2(getpriority, int, which, int, who) |
1da177e4 LT |
212 | { |
213 | struct task_struct *g, *p; | |
214 | struct user_struct *user; | |
86a264ab | 215 | const struct cred *cred = current_cred(); |
1da177e4 | 216 | long niceval, retval = -ESRCH; |
41487c65 | 217 | struct pid *pgrp; |
1da177e4 | 218 | |
3e88c553 | 219 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
220 | return -EINVAL; |
221 | ||
222 | read_lock(&tasklist_lock); | |
223 | switch (which) { | |
224 | case PRIO_PROCESS: | |
41487c65 | 225 | if (who) |
228ebcbe | 226 | p = find_task_by_vpid(who); |
41487c65 EB |
227 | else |
228 | p = current; | |
1da177e4 LT |
229 | if (p) { |
230 | niceval = 20 - task_nice(p); | |
231 | if (niceval > retval) | |
232 | retval = niceval; | |
233 | } | |
234 | break; | |
235 | case PRIO_PGRP: | |
41487c65 | 236 | if (who) |
b488893a | 237 | pgrp = find_vpid(who); |
41487c65 EB |
238 | else |
239 | pgrp = task_pgrp(current); | |
2d70b68d | 240 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 LT |
241 | niceval = 20 - task_nice(p); |
242 | if (niceval > retval) | |
243 | retval = niceval; | |
2d70b68d | 244 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
245 | break; |
246 | case PRIO_USER: | |
86a264ab | 247 | user = (struct user_struct *) cred->user; |
1da177e4 | 248 | if (!who) |
86a264ab DH |
249 | who = cred->uid; |
250 | else if ((who != cred->uid) && | |
251 | !(user = find_user(who))) | |
252 | goto out_unlock; /* No processes for this user */ | |
1da177e4 LT |
253 | |
254 | do_each_thread(g, p) | |
86a264ab | 255 | if (__task_cred(p)->uid == who) { |
1da177e4 LT |
256 | niceval = 20 - task_nice(p); |
257 | if (niceval > retval) | |
258 | retval = niceval; | |
259 | } | |
260 | while_each_thread(g, p); | |
86a264ab | 261 | if (who != cred->uid) |
1da177e4 LT |
262 | free_uid(user); /* for find_user() */ |
263 | break; | |
264 | } | |
265 | out_unlock: | |
266 | read_unlock(&tasklist_lock); | |
267 | ||
268 | return retval; | |
269 | } | |
270 | ||
e4c94330 EB |
271 | /** |
272 | * emergency_restart - reboot the system | |
273 | * | |
274 | * Without shutting down any hardware or taking any locks | |
275 | * reboot the system. This is called when we know we are in | |
276 | * trouble so this is our best effort to reboot. This is | |
277 | * safe to call in interrupt context. | |
278 | */ | |
7c903473 EB |
279 | void emergency_restart(void) |
280 | { | |
281 | machine_emergency_restart(); | |
282 | } | |
283 | EXPORT_SYMBOL_GPL(emergency_restart); | |
284 | ||
ca195b7f | 285 | void kernel_restart_prepare(char *cmd) |
4a00ea1e | 286 | { |
e041c683 | 287 | blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd); |
4a00ea1e | 288 | system_state = SYSTEM_RESTART; |
4a00ea1e | 289 | device_shutdown(); |
58b3b71d | 290 | sysdev_shutdown(); |
e4c94330 | 291 | } |
1e5d5331 RD |
292 | |
293 | /** | |
294 | * kernel_restart - reboot the system | |
295 | * @cmd: pointer to buffer containing command to execute for restart | |
b8887e6e | 296 | * or %NULL |
1e5d5331 RD |
297 | * |
298 | * Shutdown everything and perform a clean reboot. | |
299 | * This is not safe to call in interrupt context. | |
300 | */ | |
e4c94330 EB |
301 | void kernel_restart(char *cmd) |
302 | { | |
303 | kernel_restart_prepare(cmd); | |
756184b7 | 304 | if (!cmd) |
4a00ea1e | 305 | printk(KERN_EMERG "Restarting system.\n"); |
756184b7 | 306 | else |
4a00ea1e | 307 | printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd); |
4a00ea1e EB |
308 | machine_restart(cmd); |
309 | } | |
310 | EXPORT_SYMBOL_GPL(kernel_restart); | |
311 | ||
4ef7229f | 312 | static void kernel_shutdown_prepare(enum system_states state) |
729b4d4c | 313 | { |
e041c683 | 314 | blocking_notifier_call_chain(&reboot_notifier_list, |
729b4d4c AS |
315 | (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL); |
316 | system_state = state; | |
317 | device_shutdown(); | |
318 | } | |
e4c94330 EB |
319 | /** |
320 | * kernel_halt - halt the system | |
321 | * | |
322 | * Shutdown everything and perform a clean system halt. | |
323 | */ | |
e4c94330 EB |
324 | void kernel_halt(void) |
325 | { | |
729b4d4c | 326 | kernel_shutdown_prepare(SYSTEM_HALT); |
58b3b71d | 327 | sysdev_shutdown(); |
4a00ea1e EB |
328 | printk(KERN_EMERG "System halted.\n"); |
329 | machine_halt(); | |
330 | } | |
729b4d4c | 331 | |
4a00ea1e EB |
332 | EXPORT_SYMBOL_GPL(kernel_halt); |
333 | ||
e4c94330 EB |
334 | /** |
335 | * kernel_power_off - power_off the system | |
336 | * | |
337 | * Shutdown everything and perform a clean system power_off. | |
338 | */ | |
e4c94330 EB |
339 | void kernel_power_off(void) |
340 | { | |
729b4d4c | 341 | kernel_shutdown_prepare(SYSTEM_POWER_OFF); |
bd804eba RW |
342 | if (pm_power_off_prepare) |
343 | pm_power_off_prepare(); | |
4047727e | 344 | disable_nonboot_cpus(); |
58b3b71d | 345 | sysdev_shutdown(); |
4a00ea1e EB |
346 | printk(KERN_EMERG "Power down.\n"); |
347 | machine_power_off(); | |
348 | } | |
349 | EXPORT_SYMBOL_GPL(kernel_power_off); | |
1da177e4 LT |
350 | /* |
351 | * Reboot system call: for obvious reasons only root may call it, | |
352 | * and even root needs to set up some magic numbers in the registers | |
353 | * so that some mistake won't make this reboot the whole machine. | |
354 | * You can also set the meaning of the ctrl-alt-del-key here. | |
355 | * | |
356 | * reboot doesn't sync: do that yourself before calling this. | |
357 | */ | |
754fe8d2 HC |
358 | SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, |
359 | void __user *, arg) | |
1da177e4 LT |
360 | { |
361 | char buffer[256]; | |
362 | ||
363 | /* We only trust the superuser with rebooting the system. */ | |
364 | if (!capable(CAP_SYS_BOOT)) | |
365 | return -EPERM; | |
366 | ||
367 | /* For safety, we require "magic" arguments. */ | |
368 | if (magic1 != LINUX_REBOOT_MAGIC1 || | |
369 | (magic2 != LINUX_REBOOT_MAGIC2 && | |
370 | magic2 != LINUX_REBOOT_MAGIC2A && | |
371 | magic2 != LINUX_REBOOT_MAGIC2B && | |
372 | magic2 != LINUX_REBOOT_MAGIC2C)) | |
373 | return -EINVAL; | |
374 | ||
5e38291d EB |
375 | /* Instead of trying to make the power_off code look like |
376 | * halt when pm_power_off is not set do it the easy way. | |
377 | */ | |
378 | if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off) | |
379 | cmd = LINUX_REBOOT_CMD_HALT; | |
380 | ||
1da177e4 LT |
381 | lock_kernel(); |
382 | switch (cmd) { | |
383 | case LINUX_REBOOT_CMD_RESTART: | |
4a00ea1e | 384 | kernel_restart(NULL); |
1da177e4 LT |
385 | break; |
386 | ||
387 | case LINUX_REBOOT_CMD_CAD_ON: | |
388 | C_A_D = 1; | |
389 | break; | |
390 | ||
391 | case LINUX_REBOOT_CMD_CAD_OFF: | |
392 | C_A_D = 0; | |
393 | break; | |
394 | ||
395 | case LINUX_REBOOT_CMD_HALT: | |
4a00ea1e | 396 | kernel_halt(); |
1da177e4 LT |
397 | unlock_kernel(); |
398 | do_exit(0); | |
399 | break; | |
400 | ||
401 | case LINUX_REBOOT_CMD_POWER_OFF: | |
4a00ea1e | 402 | kernel_power_off(); |
1da177e4 LT |
403 | unlock_kernel(); |
404 | do_exit(0); | |
405 | break; | |
406 | ||
407 | case LINUX_REBOOT_CMD_RESTART2: | |
408 | if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) { | |
409 | unlock_kernel(); | |
410 | return -EFAULT; | |
411 | } | |
412 | buffer[sizeof(buffer) - 1] = '\0'; | |
413 | ||
4a00ea1e | 414 | kernel_restart(buffer); |
1da177e4 LT |
415 | break; |
416 | ||
3ab83521 | 417 | #ifdef CONFIG_KEXEC |
dc009d92 | 418 | case LINUX_REBOOT_CMD_KEXEC: |
3ab83521 HY |
419 | { |
420 | int ret; | |
421 | ret = kernel_kexec(); | |
422 | unlock_kernel(); | |
423 | return ret; | |
424 | } | |
425 | #endif | |
4a00ea1e | 426 | |
b0cb1a19 | 427 | #ifdef CONFIG_HIBERNATION |
1da177e4 LT |
428 | case LINUX_REBOOT_CMD_SW_SUSPEND: |
429 | { | |
a3d25c27 | 430 | int ret = hibernate(); |
1da177e4 LT |
431 | unlock_kernel(); |
432 | return ret; | |
433 | } | |
434 | #endif | |
435 | ||
436 | default: | |
437 | unlock_kernel(); | |
438 | return -EINVAL; | |
439 | } | |
440 | unlock_kernel(); | |
441 | return 0; | |
442 | } | |
443 | ||
65f27f38 | 444 | static void deferred_cad(struct work_struct *dummy) |
1da177e4 | 445 | { |
abcd9e51 | 446 | kernel_restart(NULL); |
1da177e4 LT |
447 | } |
448 | ||
449 | /* | |
450 | * This function gets called by ctrl-alt-del - ie the keyboard interrupt. | |
451 | * As it's called within an interrupt, it may NOT sync: the only choice | |
452 | * is whether to reboot at once, or just ignore the ctrl-alt-del. | |
453 | */ | |
454 | void ctrl_alt_del(void) | |
455 | { | |
65f27f38 | 456 | static DECLARE_WORK(cad_work, deferred_cad); |
1da177e4 LT |
457 | |
458 | if (C_A_D) | |
459 | schedule_work(&cad_work); | |
460 | else | |
9ec52099 | 461 | kill_cad_pid(SIGINT, 1); |
1da177e4 LT |
462 | } |
463 | ||
1da177e4 LT |
464 | /* |
465 | * Unprivileged users may change the real gid to the effective gid | |
466 | * or vice versa. (BSD-style) | |
467 | * | |
468 | * If you set the real gid at all, or set the effective gid to a value not | |
469 | * equal to the real gid, then the saved gid is set to the new effective gid. | |
470 | * | |
471 | * This makes it possible for a setgid program to completely drop its | |
472 | * privileges, which is often a useful assertion to make when you are doing | |
473 | * a security audit over a program. | |
474 | * | |
475 | * The general idea is that a program which uses just setregid() will be | |
476 | * 100% compatible with BSD. A program which uses just setgid() will be | |
477 | * 100% compatible with POSIX with saved IDs. | |
478 | * | |
479 | * SMP: There are not races, the GIDs are checked only by filesystem | |
480 | * operations (as far as semantic preservation is concerned). | |
481 | */ | |
ae1251ab | 482 | SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) |
1da177e4 | 483 | { |
d84f4f99 DH |
484 | const struct cred *old; |
485 | struct cred *new; | |
1da177e4 LT |
486 | int retval; |
487 | ||
d84f4f99 DH |
488 | new = prepare_creds(); |
489 | if (!new) | |
490 | return -ENOMEM; | |
491 | old = current_cred(); | |
492 | ||
1da177e4 LT |
493 | retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE); |
494 | if (retval) | |
d84f4f99 | 495 | goto error; |
1da177e4 | 496 | |
d84f4f99 | 497 | retval = -EPERM; |
1da177e4 | 498 | if (rgid != (gid_t) -1) { |
d84f4f99 DH |
499 | if (old->gid == rgid || |
500 | old->egid == rgid || | |
1da177e4 | 501 | capable(CAP_SETGID)) |
d84f4f99 | 502 | new->gid = rgid; |
1da177e4 | 503 | else |
d84f4f99 | 504 | goto error; |
1da177e4 LT |
505 | } |
506 | if (egid != (gid_t) -1) { | |
d84f4f99 DH |
507 | if (old->gid == egid || |
508 | old->egid == egid || | |
509 | old->sgid == egid || | |
1da177e4 | 510 | capable(CAP_SETGID)) |
d84f4f99 | 511 | new->egid = egid; |
756184b7 | 512 | else |
d84f4f99 | 513 | goto error; |
1da177e4 | 514 | } |
d84f4f99 | 515 | |
1da177e4 | 516 | if (rgid != (gid_t) -1 || |
d84f4f99 DH |
517 | (egid != (gid_t) -1 && egid != old->gid)) |
518 | new->sgid = new->egid; | |
519 | new->fsgid = new->egid; | |
520 | ||
521 | return commit_creds(new); | |
522 | ||
523 | error: | |
524 | abort_creds(new); | |
525 | return retval; | |
1da177e4 LT |
526 | } |
527 | ||
528 | /* | |
529 | * setgid() is implemented like SysV w/ SAVED_IDS | |
530 | * | |
531 | * SMP: Same implicit races as above. | |
532 | */ | |
ae1251ab | 533 | SYSCALL_DEFINE1(setgid, gid_t, gid) |
1da177e4 | 534 | { |
d84f4f99 DH |
535 | const struct cred *old; |
536 | struct cred *new; | |
1da177e4 LT |
537 | int retval; |
538 | ||
d84f4f99 DH |
539 | new = prepare_creds(); |
540 | if (!new) | |
541 | return -ENOMEM; | |
542 | old = current_cred(); | |
543 | ||
1da177e4 LT |
544 | retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID); |
545 | if (retval) | |
d84f4f99 | 546 | goto error; |
1da177e4 | 547 | |
d84f4f99 DH |
548 | retval = -EPERM; |
549 | if (capable(CAP_SETGID)) | |
550 | new->gid = new->egid = new->sgid = new->fsgid = gid; | |
551 | else if (gid == old->gid || gid == old->sgid) | |
552 | new->egid = new->fsgid = gid; | |
1da177e4 | 553 | else |
d84f4f99 | 554 | goto error; |
1da177e4 | 555 | |
d84f4f99 DH |
556 | return commit_creds(new); |
557 | ||
558 | error: | |
559 | abort_creds(new); | |
560 | return retval; | |
1da177e4 LT |
561 | } |
562 | ||
d84f4f99 DH |
563 | /* |
564 | * change the user struct in a credentials set to match the new UID | |
565 | */ | |
566 | static int set_user(struct cred *new) | |
1da177e4 LT |
567 | { |
568 | struct user_struct *new_user; | |
569 | ||
18b6e041 | 570 | new_user = alloc_uid(current_user_ns(), new->uid); |
1da177e4 LT |
571 | if (!new_user) |
572 | return -EAGAIN; | |
573 | ||
574 | if (atomic_read(&new_user->processes) >= | |
575 | current->signal->rlim[RLIMIT_NPROC].rlim_cur && | |
18b6e041 | 576 | new_user != INIT_USER) { |
1da177e4 LT |
577 | free_uid(new_user); |
578 | return -EAGAIN; | |
579 | } | |
580 | ||
d84f4f99 DH |
581 | free_uid(new->user); |
582 | new->user = new_user; | |
1da177e4 LT |
583 | return 0; |
584 | } | |
585 | ||
586 | /* | |
587 | * Unprivileged users may change the real uid to the effective uid | |
588 | * or vice versa. (BSD-style) | |
589 | * | |
590 | * If you set the real uid at all, or set the effective uid to a value not | |
591 | * equal to the real uid, then the saved uid is set to the new effective uid. | |
592 | * | |
593 | * This makes it possible for a setuid program to completely drop its | |
594 | * privileges, which is often a useful assertion to make when you are doing | |
595 | * a security audit over a program. | |
596 | * | |
597 | * The general idea is that a program which uses just setreuid() will be | |
598 | * 100% compatible with BSD. A program which uses just setuid() will be | |
599 | * 100% compatible with POSIX with saved IDs. | |
600 | */ | |
ae1251ab | 601 | SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) |
1da177e4 | 602 | { |
d84f4f99 DH |
603 | const struct cred *old; |
604 | struct cred *new; | |
1da177e4 LT |
605 | int retval; |
606 | ||
d84f4f99 DH |
607 | new = prepare_creds(); |
608 | if (!new) | |
609 | return -ENOMEM; | |
610 | old = current_cred(); | |
611 | ||
1da177e4 LT |
612 | retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE); |
613 | if (retval) | |
d84f4f99 | 614 | goto error; |
1da177e4 | 615 | |
d84f4f99 | 616 | retval = -EPERM; |
1da177e4 | 617 | if (ruid != (uid_t) -1) { |
d84f4f99 DH |
618 | new->uid = ruid; |
619 | if (old->uid != ruid && | |
620 | old->euid != ruid && | |
1da177e4 | 621 | !capable(CAP_SETUID)) |
d84f4f99 | 622 | goto error; |
1da177e4 LT |
623 | } |
624 | ||
625 | if (euid != (uid_t) -1) { | |
d84f4f99 DH |
626 | new->euid = euid; |
627 | if (old->uid != euid && | |
628 | old->euid != euid && | |
629 | old->suid != euid && | |
1da177e4 | 630 | !capable(CAP_SETUID)) |
d84f4f99 | 631 | goto error; |
1da177e4 LT |
632 | } |
633 | ||
d84f4f99 DH |
634 | retval = -EAGAIN; |
635 | if (new->uid != old->uid && set_user(new) < 0) | |
636 | goto error; | |
1da177e4 | 637 | |
1da177e4 | 638 | if (ruid != (uid_t) -1 || |
d84f4f99 DH |
639 | (euid != (uid_t) -1 && euid != old->uid)) |
640 | new->suid = new->euid; | |
641 | new->fsuid = new->euid; | |
1da177e4 | 642 | |
d84f4f99 DH |
643 | retval = security_task_fix_setuid(new, old, LSM_SETID_RE); |
644 | if (retval < 0) | |
645 | goto error; | |
1da177e4 | 646 | |
d84f4f99 | 647 | return commit_creds(new); |
1da177e4 | 648 | |
d84f4f99 DH |
649 | error: |
650 | abort_creds(new); | |
651 | return retval; | |
652 | } | |
1da177e4 LT |
653 | |
654 | /* | |
655 | * setuid() is implemented like SysV with SAVED_IDS | |
656 | * | |
657 | * Note that SAVED_ID's is deficient in that a setuid root program | |
658 | * like sendmail, for example, cannot set its uid to be a normal | |
659 | * user and then switch back, because if you're root, setuid() sets | |
660 | * the saved uid too. If you don't like this, blame the bright people | |
661 | * in the POSIX committee and/or USG. Note that the BSD-style setreuid() | |
662 | * will allow a root program to temporarily drop privileges and be able to | |
663 | * regain them by swapping the real and effective uid. | |
664 | */ | |
ae1251ab | 665 | SYSCALL_DEFINE1(setuid, uid_t, uid) |
1da177e4 | 666 | { |
d84f4f99 DH |
667 | const struct cred *old; |
668 | struct cred *new; | |
1da177e4 LT |
669 | int retval; |
670 | ||
d84f4f99 DH |
671 | new = prepare_creds(); |
672 | if (!new) | |
673 | return -ENOMEM; | |
674 | old = current_cred(); | |
675 | ||
1da177e4 LT |
676 | retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID); |
677 | if (retval) | |
d84f4f99 | 678 | goto error; |
1da177e4 | 679 | |
d84f4f99 | 680 | retval = -EPERM; |
1da177e4 | 681 | if (capable(CAP_SETUID)) { |
d84f4f99 DH |
682 | new->suid = new->uid = uid; |
683 | if (uid != old->uid && set_user(new) < 0) { | |
684 | retval = -EAGAIN; | |
685 | goto error; | |
686 | } | |
687 | } else if (uid != old->uid && uid != new->suid) { | |
688 | goto error; | |
1da177e4 | 689 | } |
1da177e4 | 690 | |
d84f4f99 DH |
691 | new->fsuid = new->euid = uid; |
692 | ||
693 | retval = security_task_fix_setuid(new, old, LSM_SETID_ID); | |
694 | if (retval < 0) | |
695 | goto error; | |
696 | ||
697 | return commit_creds(new); | |
1da177e4 | 698 | |
d84f4f99 DH |
699 | error: |
700 | abort_creds(new); | |
701 | return retval; | |
1da177e4 LT |
702 | } |
703 | ||
704 | ||
705 | /* | |
706 | * This function implements a generic ability to update ruid, euid, | |
707 | * and suid. This allows you to implement the 4.4 compatible seteuid(). | |
708 | */ | |
ae1251ab | 709 | SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) |
1da177e4 | 710 | { |
d84f4f99 DH |
711 | const struct cred *old; |
712 | struct cred *new; | |
1da177e4 LT |
713 | int retval; |
714 | ||
d84f4f99 DH |
715 | new = prepare_creds(); |
716 | if (!new) | |
717 | return -ENOMEM; | |
718 | ||
1da177e4 LT |
719 | retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES); |
720 | if (retval) | |
d84f4f99 DH |
721 | goto error; |
722 | old = current_cred(); | |
1da177e4 | 723 | |
d84f4f99 | 724 | retval = -EPERM; |
1da177e4 | 725 | if (!capable(CAP_SETUID)) { |
d84f4f99 DH |
726 | if (ruid != (uid_t) -1 && ruid != old->uid && |
727 | ruid != old->euid && ruid != old->suid) | |
728 | goto error; | |
729 | if (euid != (uid_t) -1 && euid != old->uid && | |
730 | euid != old->euid && euid != old->suid) | |
731 | goto error; | |
732 | if (suid != (uid_t) -1 && suid != old->uid && | |
733 | suid != old->euid && suid != old->suid) | |
734 | goto error; | |
1da177e4 | 735 | } |
d84f4f99 DH |
736 | |
737 | retval = -EAGAIN; | |
1da177e4 | 738 | if (ruid != (uid_t) -1) { |
d84f4f99 DH |
739 | new->uid = ruid; |
740 | if (ruid != old->uid && set_user(new) < 0) | |
741 | goto error; | |
1da177e4 | 742 | } |
d84f4f99 DH |
743 | if (euid != (uid_t) -1) |
744 | new->euid = euid; | |
1da177e4 | 745 | if (suid != (uid_t) -1) |
d84f4f99 DH |
746 | new->suid = suid; |
747 | new->fsuid = new->euid; | |
1da177e4 | 748 | |
d84f4f99 DH |
749 | retval = security_task_fix_setuid(new, old, LSM_SETID_RES); |
750 | if (retval < 0) | |
751 | goto error; | |
1da177e4 | 752 | |
d84f4f99 DH |
753 | return commit_creds(new); |
754 | ||
755 | error: | |
756 | abort_creds(new); | |
757 | return retval; | |
1da177e4 LT |
758 | } |
759 | ||
dbf040d9 | 760 | SYSCALL_DEFINE3(getresuid, uid_t __user *, ruid, uid_t __user *, euid, uid_t __user *, suid) |
1da177e4 | 761 | { |
86a264ab | 762 | const struct cred *cred = current_cred(); |
1da177e4 LT |
763 | int retval; |
764 | ||
86a264ab DH |
765 | if (!(retval = put_user(cred->uid, ruid)) && |
766 | !(retval = put_user(cred->euid, euid))) | |
b6dff3ec | 767 | retval = put_user(cred->suid, suid); |
1da177e4 LT |
768 | |
769 | return retval; | |
770 | } | |
771 | ||
772 | /* | |
773 | * Same as above, but for rgid, egid, sgid. | |
774 | */ | |
ae1251ab | 775 | SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) |
1da177e4 | 776 | { |
d84f4f99 DH |
777 | const struct cred *old; |
778 | struct cred *new; | |
1da177e4 LT |
779 | int retval; |
780 | ||
d84f4f99 DH |
781 | new = prepare_creds(); |
782 | if (!new) | |
783 | return -ENOMEM; | |
784 | old = current_cred(); | |
785 | ||
1da177e4 LT |
786 | retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES); |
787 | if (retval) | |
d84f4f99 | 788 | goto error; |
1da177e4 | 789 | |
d84f4f99 | 790 | retval = -EPERM; |
1da177e4 | 791 | if (!capable(CAP_SETGID)) { |
d84f4f99 DH |
792 | if (rgid != (gid_t) -1 && rgid != old->gid && |
793 | rgid != old->egid && rgid != old->sgid) | |
794 | goto error; | |
795 | if (egid != (gid_t) -1 && egid != old->gid && | |
796 | egid != old->egid && egid != old->sgid) | |
797 | goto error; | |
798 | if (sgid != (gid_t) -1 && sgid != old->gid && | |
799 | sgid != old->egid && sgid != old->sgid) | |
800 | goto error; | |
1da177e4 | 801 | } |
d84f4f99 | 802 | |
1da177e4 | 803 | if (rgid != (gid_t) -1) |
d84f4f99 DH |
804 | new->gid = rgid; |
805 | if (egid != (gid_t) -1) | |
806 | new->egid = egid; | |
1da177e4 | 807 | if (sgid != (gid_t) -1) |
d84f4f99 DH |
808 | new->sgid = sgid; |
809 | new->fsgid = new->egid; | |
1da177e4 | 810 | |
d84f4f99 DH |
811 | return commit_creds(new); |
812 | ||
813 | error: | |
814 | abort_creds(new); | |
815 | return retval; | |
1da177e4 LT |
816 | } |
817 | ||
dbf040d9 | 818 | SYSCALL_DEFINE3(getresgid, gid_t __user *, rgid, gid_t __user *, egid, gid_t __user *, sgid) |
1da177e4 | 819 | { |
86a264ab | 820 | const struct cred *cred = current_cred(); |
1da177e4 LT |
821 | int retval; |
822 | ||
86a264ab DH |
823 | if (!(retval = put_user(cred->gid, rgid)) && |
824 | !(retval = put_user(cred->egid, egid))) | |
b6dff3ec | 825 | retval = put_user(cred->sgid, sgid); |
1da177e4 LT |
826 | |
827 | return retval; | |
828 | } | |
829 | ||
830 | ||
831 | /* | |
832 | * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This | |
833 | * is used for "access()" and for the NFS daemon (letting nfsd stay at | |
834 | * whatever uid it wants to). It normally shadows "euid", except when | |
835 | * explicitly set by setfsuid() or for access.. | |
836 | */ | |
ae1251ab | 837 | SYSCALL_DEFINE1(setfsuid, uid_t, uid) |
1da177e4 | 838 | { |
d84f4f99 DH |
839 | const struct cred *old; |
840 | struct cred *new; | |
841 | uid_t old_fsuid; | |
842 | ||
843 | new = prepare_creds(); | |
844 | if (!new) | |
845 | return current_fsuid(); | |
846 | old = current_cred(); | |
847 | old_fsuid = old->fsuid; | |
1da177e4 | 848 | |
d84f4f99 DH |
849 | if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS) < 0) |
850 | goto error; | |
1da177e4 | 851 | |
d84f4f99 DH |
852 | if (uid == old->uid || uid == old->euid || |
853 | uid == old->suid || uid == old->fsuid || | |
756184b7 CP |
854 | capable(CAP_SETUID)) { |
855 | if (uid != old_fsuid) { | |
d84f4f99 DH |
856 | new->fsuid = uid; |
857 | if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) | |
858 | goto change_okay; | |
1da177e4 | 859 | } |
1da177e4 LT |
860 | } |
861 | ||
d84f4f99 DH |
862 | error: |
863 | abort_creds(new); | |
864 | return old_fsuid; | |
1da177e4 | 865 | |
d84f4f99 DH |
866 | change_okay: |
867 | commit_creds(new); | |
1da177e4 LT |
868 | return old_fsuid; |
869 | } | |
870 | ||
871 | /* | |
f42df9e6 | 872 | * Samma på svenska.. |
1da177e4 | 873 | */ |
ae1251ab | 874 | SYSCALL_DEFINE1(setfsgid, gid_t, gid) |
1da177e4 | 875 | { |
d84f4f99 DH |
876 | const struct cred *old; |
877 | struct cred *new; | |
878 | gid_t old_fsgid; | |
879 | ||
880 | new = prepare_creds(); | |
881 | if (!new) | |
882 | return current_fsgid(); | |
883 | old = current_cred(); | |
884 | old_fsgid = old->fsgid; | |
1da177e4 | 885 | |
1da177e4 | 886 | if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS)) |
d84f4f99 | 887 | goto error; |
1da177e4 | 888 | |
d84f4f99 DH |
889 | if (gid == old->gid || gid == old->egid || |
890 | gid == old->sgid || gid == old->fsgid || | |
756184b7 CP |
891 | capable(CAP_SETGID)) { |
892 | if (gid != old_fsgid) { | |
d84f4f99 DH |
893 | new->fsgid = gid; |
894 | goto change_okay; | |
1da177e4 | 895 | } |
1da177e4 | 896 | } |
d84f4f99 DH |
897 | |
898 | error: | |
899 | abort_creds(new); | |
900 | return old_fsgid; | |
901 | ||
902 | change_okay: | |
903 | commit_creds(new); | |
1da177e4 LT |
904 | return old_fsgid; |
905 | } | |
906 | ||
f06febc9 FM |
907 | void do_sys_times(struct tms *tms) |
908 | { | |
909 | struct task_cputime cputime; | |
910 | cputime_t cutime, cstime; | |
911 | ||
f06febc9 | 912 | thread_group_cputime(current, &cputime); |
2b5fe6de | 913 | spin_lock_irq(¤t->sighand->siglock); |
f06febc9 FM |
914 | cutime = current->signal->cutime; |
915 | cstime = current->signal->cstime; | |
916 | spin_unlock_irq(¤t->sighand->siglock); | |
917 | tms->tms_utime = cputime_to_clock_t(cputime.utime); | |
918 | tms->tms_stime = cputime_to_clock_t(cputime.stime); | |
919 | tms->tms_cutime = cputime_to_clock_t(cutime); | |
920 | tms->tms_cstime = cputime_to_clock_t(cstime); | |
921 | } | |
922 | ||
58fd3aa2 | 923 | SYSCALL_DEFINE1(times, struct tms __user *, tbuf) |
1da177e4 | 924 | { |
1da177e4 LT |
925 | if (tbuf) { |
926 | struct tms tmp; | |
f06febc9 FM |
927 | |
928 | do_sys_times(&tmp); | |
1da177e4 LT |
929 | if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
930 | return -EFAULT; | |
931 | } | |
e3d5a27d | 932 | force_successful_syscall_return(); |
1da177e4 LT |
933 | return (long) jiffies_64_to_clock_t(get_jiffies_64()); |
934 | } | |
935 | ||
936 | /* | |
937 | * This needs some heavy checking ... | |
938 | * I just haven't the stomach for it. I also don't fully | |
939 | * understand sessions/pgrp etc. Let somebody who does explain it. | |
940 | * | |
941 | * OK, I think I have the protection semantics right.... this is really | |
942 | * only important on a multi-user system anyway, to make sure one user | |
943 | * can't send a signal to a process owned by another. -TYT, 12/12/91 | |
944 | * | |
945 | * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. | |
946 | * LBT 04.03.94 | |
947 | */ | |
b290ebe2 | 948 | SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) |
1da177e4 LT |
949 | { |
950 | struct task_struct *p; | |
ee0acf90 | 951 | struct task_struct *group_leader = current->group_leader; |
4e021306 ON |
952 | struct pid *pgrp; |
953 | int err; | |
1da177e4 LT |
954 | |
955 | if (!pid) | |
b488893a | 956 | pid = task_pid_vnr(group_leader); |
1da177e4 LT |
957 | if (!pgid) |
958 | pgid = pid; | |
959 | if (pgid < 0) | |
960 | return -EINVAL; | |
961 | ||
962 | /* From this point forward we keep holding onto the tasklist lock | |
963 | * so that our parent does not change from under us. -DaveM | |
964 | */ | |
965 | write_lock_irq(&tasklist_lock); | |
966 | ||
967 | err = -ESRCH; | |
4e021306 | 968 | p = find_task_by_vpid(pid); |
1da177e4 LT |
969 | if (!p) |
970 | goto out; | |
971 | ||
972 | err = -EINVAL; | |
973 | if (!thread_group_leader(p)) | |
974 | goto out; | |
975 | ||
4e021306 | 976 | if (same_thread_group(p->real_parent, group_leader)) { |
1da177e4 | 977 | err = -EPERM; |
41487c65 | 978 | if (task_session(p) != task_session(group_leader)) |
1da177e4 LT |
979 | goto out; |
980 | err = -EACCES; | |
981 | if (p->did_exec) | |
982 | goto out; | |
983 | } else { | |
984 | err = -ESRCH; | |
ee0acf90 | 985 | if (p != group_leader) |
1da177e4 LT |
986 | goto out; |
987 | } | |
988 | ||
989 | err = -EPERM; | |
990 | if (p->signal->leader) | |
991 | goto out; | |
992 | ||
4e021306 | 993 | pgrp = task_pid(p); |
1da177e4 | 994 | if (pgid != pid) { |
b488893a | 995 | struct task_struct *g; |
1da177e4 | 996 | |
4e021306 ON |
997 | pgrp = find_vpid(pgid); |
998 | g = pid_task(pgrp, PIDTYPE_PGID); | |
41487c65 | 999 | if (!g || task_session(g) != task_session(group_leader)) |
f020bc46 | 1000 | goto out; |
1da177e4 LT |
1001 | } |
1002 | ||
1da177e4 LT |
1003 | err = security_task_setpgid(p, pgid); |
1004 | if (err) | |
1005 | goto out; | |
1006 | ||
4e021306 | 1007 | if (task_pgrp(p) != pgrp) { |
83beaf3c | 1008 | change_pid(p, PIDTYPE_PGID, pgrp); |
4e021306 | 1009 | set_task_pgrp(p, pid_nr(pgrp)); |
1da177e4 LT |
1010 | } |
1011 | ||
1012 | err = 0; | |
1013 | out: | |
1014 | /* All paths lead to here, thus we are safe. -DaveM */ | |
1015 | write_unlock_irq(&tasklist_lock); | |
1016 | return err; | |
1017 | } | |
1018 | ||
dbf040d9 | 1019 | SYSCALL_DEFINE1(getpgid, pid_t, pid) |
1da177e4 | 1020 | { |
12a3de0a ON |
1021 | struct task_struct *p; |
1022 | struct pid *grp; | |
1023 | int retval; | |
1024 | ||
1025 | rcu_read_lock(); | |
756184b7 | 1026 | if (!pid) |
12a3de0a | 1027 | grp = task_pgrp(current); |
756184b7 | 1028 | else { |
1da177e4 | 1029 | retval = -ESRCH; |
12a3de0a ON |
1030 | p = find_task_by_vpid(pid); |
1031 | if (!p) | |
1032 | goto out; | |
1033 | grp = task_pgrp(p); | |
1034 | if (!grp) | |
1035 | goto out; | |
1036 | ||
1037 | retval = security_task_getpgid(p); | |
1038 | if (retval) | |
1039 | goto out; | |
1da177e4 | 1040 | } |
12a3de0a ON |
1041 | retval = pid_vnr(grp); |
1042 | out: | |
1043 | rcu_read_unlock(); | |
1044 | return retval; | |
1da177e4 LT |
1045 | } |
1046 | ||
1047 | #ifdef __ARCH_WANT_SYS_GETPGRP | |
1048 | ||
dbf040d9 | 1049 | SYSCALL_DEFINE0(getpgrp) |
1da177e4 | 1050 | { |
12a3de0a | 1051 | return sys_getpgid(0); |
1da177e4 LT |
1052 | } |
1053 | ||
1054 | #endif | |
1055 | ||
dbf040d9 | 1056 | SYSCALL_DEFINE1(getsid, pid_t, pid) |
1da177e4 | 1057 | { |
1dd768c0 ON |
1058 | struct task_struct *p; |
1059 | struct pid *sid; | |
1060 | int retval; | |
1061 | ||
1062 | rcu_read_lock(); | |
756184b7 | 1063 | if (!pid) |
1dd768c0 | 1064 | sid = task_session(current); |
756184b7 | 1065 | else { |
1da177e4 | 1066 | retval = -ESRCH; |
1dd768c0 ON |
1067 | p = find_task_by_vpid(pid); |
1068 | if (!p) | |
1069 | goto out; | |
1070 | sid = task_session(p); | |
1071 | if (!sid) | |
1072 | goto out; | |
1073 | ||
1074 | retval = security_task_getsid(p); | |
1075 | if (retval) | |
1076 | goto out; | |
1da177e4 | 1077 | } |
1dd768c0 ON |
1078 | retval = pid_vnr(sid); |
1079 | out: | |
1080 | rcu_read_unlock(); | |
1081 | return retval; | |
1da177e4 LT |
1082 | } |
1083 | ||
b290ebe2 | 1084 | SYSCALL_DEFINE0(setsid) |
1da177e4 | 1085 | { |
e19f247a | 1086 | struct task_struct *group_leader = current->group_leader; |
e4cc0a9c ON |
1087 | struct pid *sid = task_pid(group_leader); |
1088 | pid_t session = pid_vnr(sid); | |
1da177e4 LT |
1089 | int err = -EPERM; |
1090 | ||
1da177e4 | 1091 | write_lock_irq(&tasklist_lock); |
390e2ff0 EB |
1092 | /* Fail if I am already a session leader */ |
1093 | if (group_leader->signal->leader) | |
1094 | goto out; | |
1095 | ||
430c6231 ON |
1096 | /* Fail if a process group id already exists that equals the |
1097 | * proposed session id. | |
390e2ff0 | 1098 | */ |
6806aac6 | 1099 | if (pid_task(sid, PIDTYPE_PGID)) |
1da177e4 LT |
1100 | goto out; |
1101 | ||
e19f247a | 1102 | group_leader->signal->leader = 1; |
8520d7c7 | 1103 | __set_special_pids(sid); |
24ec839c | 1104 | |
9c9f4ded | 1105 | proc_clear_tty(group_leader); |
24ec839c | 1106 | |
e4cc0a9c | 1107 | err = session; |
1da177e4 LT |
1108 | out: |
1109 | write_unlock_irq(&tasklist_lock); | |
1da177e4 LT |
1110 | return err; |
1111 | } | |
1112 | ||
1113 | /* | |
1114 | * Supplementary group IDs | |
1115 | */ | |
1116 | ||
1117 | /* init to 2 - one for init_task, one to ensure it is never freed */ | |
1118 | struct group_info init_groups = { .usage = ATOMIC_INIT(2) }; | |
1119 | ||
1120 | struct group_info *groups_alloc(int gidsetsize) | |
1121 | { | |
1122 | struct group_info *group_info; | |
1123 | int nblocks; | |
1124 | int i; | |
1125 | ||
1126 | nblocks = (gidsetsize + NGROUPS_PER_BLOCK - 1) / NGROUPS_PER_BLOCK; | |
1127 | /* Make sure we always allocate at least one indirect block pointer */ | |
1128 | nblocks = nblocks ? : 1; | |
1129 | group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *), GFP_USER); | |
1130 | if (!group_info) | |
1131 | return NULL; | |
1132 | group_info->ngroups = gidsetsize; | |
1133 | group_info->nblocks = nblocks; | |
1134 | atomic_set(&group_info->usage, 1); | |
1135 | ||
756184b7 | 1136 | if (gidsetsize <= NGROUPS_SMALL) |
1da177e4 | 1137 | group_info->blocks[0] = group_info->small_block; |
756184b7 | 1138 | else { |
1da177e4 LT |
1139 | for (i = 0; i < nblocks; i++) { |
1140 | gid_t *b; | |
1141 | b = (void *)__get_free_page(GFP_USER); | |
1142 | if (!b) | |
1143 | goto out_undo_partial_alloc; | |
1144 | group_info->blocks[i] = b; | |
1145 | } | |
1146 | } | |
1147 | return group_info; | |
1148 | ||
1149 | out_undo_partial_alloc: | |
1150 | while (--i >= 0) { | |
1151 | free_page((unsigned long)group_info->blocks[i]); | |
1152 | } | |
1153 | kfree(group_info); | |
1154 | return NULL; | |
1155 | } | |
1156 | ||
1157 | EXPORT_SYMBOL(groups_alloc); | |
1158 | ||
1159 | void groups_free(struct group_info *group_info) | |
1160 | { | |
1161 | if (group_info->blocks[0] != group_info->small_block) { | |
1162 | int i; | |
1163 | for (i = 0; i < group_info->nblocks; i++) | |
1164 | free_page((unsigned long)group_info->blocks[i]); | |
1165 | } | |
1166 | kfree(group_info); | |
1167 | } | |
1168 | ||
1169 | EXPORT_SYMBOL(groups_free); | |
1170 | ||
1171 | /* export the group_info to a user-space array */ | |
1172 | static int groups_to_user(gid_t __user *grouplist, | |
d84f4f99 | 1173 | const struct group_info *group_info) |
1da177e4 LT |
1174 | { |
1175 | int i; | |
1bf47346 | 1176 | unsigned int count = group_info->ngroups; |
1da177e4 LT |
1177 | |
1178 | for (i = 0; i < group_info->nblocks; i++) { | |
1bf47346 ED |
1179 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
1180 | unsigned int len = cp_count * sizeof(*grouplist); | |
1da177e4 | 1181 | |
1bf47346 | 1182 | if (copy_to_user(grouplist, group_info->blocks[i], len)) |
1da177e4 LT |
1183 | return -EFAULT; |
1184 | ||
1bf47346 | 1185 | grouplist += NGROUPS_PER_BLOCK; |
1da177e4 LT |
1186 | count -= cp_count; |
1187 | } | |
1188 | return 0; | |
1189 | } | |
1190 | ||
1191 | /* fill a group_info from a user-space array - it must be allocated already */ | |
1192 | static int groups_from_user(struct group_info *group_info, | |
1193 | gid_t __user *grouplist) | |
756184b7 | 1194 | { |
1da177e4 | 1195 | int i; |
1bf47346 | 1196 | unsigned int count = group_info->ngroups; |
1da177e4 LT |
1197 | |
1198 | for (i = 0; i < group_info->nblocks; i++) { | |
1bf47346 ED |
1199 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
1200 | unsigned int len = cp_count * sizeof(*grouplist); | |
1da177e4 | 1201 | |
1bf47346 | 1202 | if (copy_from_user(group_info->blocks[i], grouplist, len)) |
1da177e4 LT |
1203 | return -EFAULT; |
1204 | ||
1bf47346 | 1205 | grouplist += NGROUPS_PER_BLOCK; |
1da177e4 LT |
1206 | count -= cp_count; |
1207 | } | |
1208 | return 0; | |
1209 | } | |
1210 | ||
ebe8b541 | 1211 | /* a simple Shell sort */ |
1da177e4 LT |
1212 | static void groups_sort(struct group_info *group_info) |
1213 | { | |
1214 | int base, max, stride; | |
1215 | int gidsetsize = group_info->ngroups; | |
1216 | ||
1217 | for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1) | |
1218 | ; /* nothing */ | |
1219 | stride /= 3; | |
1220 | ||
1221 | while (stride) { | |
1222 | max = gidsetsize - stride; | |
1223 | for (base = 0; base < max; base++) { | |
1224 | int left = base; | |
1225 | int right = left + stride; | |
1226 | gid_t tmp = GROUP_AT(group_info, right); | |
1227 | ||
1228 | while (left >= 0 && GROUP_AT(group_info, left) > tmp) { | |
1229 | GROUP_AT(group_info, right) = | |
1230 | GROUP_AT(group_info, left); | |
1231 | right = left; | |
1232 | left -= stride; | |
1233 | } | |
1234 | GROUP_AT(group_info, right) = tmp; | |
1235 | } | |
1236 | stride /= 3; | |
1237 | } | |
1238 | } | |
1239 | ||
1240 | /* a simple bsearch */ | |
86a264ab | 1241 | int groups_search(const struct group_info *group_info, gid_t grp) |
1da177e4 | 1242 | { |
d74beb9f | 1243 | unsigned int left, right; |
1da177e4 LT |
1244 | |
1245 | if (!group_info) | |
1246 | return 0; | |
1247 | ||
1248 | left = 0; | |
1249 | right = group_info->ngroups; | |
1250 | while (left < right) { | |
d74beb9f | 1251 | unsigned int mid = (left+right)/2; |
1da177e4 LT |
1252 | int cmp = grp - GROUP_AT(group_info, mid); |
1253 | if (cmp > 0) | |
1254 | left = mid + 1; | |
1255 | else if (cmp < 0) | |
1256 | right = mid; | |
1257 | else | |
1258 | return 1; | |
1259 | } | |
1260 | return 0; | |
1261 | } | |
1262 | ||
b6dff3ec | 1263 | /** |
d84f4f99 DH |
1264 | * set_groups - Change a group subscription in a set of credentials |
1265 | * @new: The newly prepared set of credentials to alter | |
1266 | * @group_info: The group list to install | |
b6dff3ec | 1267 | * |
d84f4f99 DH |
1268 | * Validate a group subscription and, if valid, insert it into a set |
1269 | * of credentials. | |
b6dff3ec | 1270 | */ |
d84f4f99 | 1271 | int set_groups(struct cred *new, struct group_info *group_info) |
1da177e4 LT |
1272 | { |
1273 | int retval; | |
1da177e4 LT |
1274 | |
1275 | retval = security_task_setgroups(group_info); | |
1276 | if (retval) | |
1277 | return retval; | |
1278 | ||
d84f4f99 | 1279 | put_group_info(new->group_info); |
1da177e4 LT |
1280 | groups_sort(group_info); |
1281 | get_group_info(group_info); | |
d84f4f99 | 1282 | new->group_info = group_info; |
1da177e4 LT |
1283 | return 0; |
1284 | } | |
1285 | ||
b6dff3ec DH |
1286 | EXPORT_SYMBOL(set_groups); |
1287 | ||
1288 | /** | |
1289 | * set_current_groups - Change current's group subscription | |
1290 | * @group_info: The group list to impose | |
1291 | * | |
1292 | * Validate a group subscription and, if valid, impose it upon current's task | |
1293 | * security record. | |
1294 | */ | |
1295 | int set_current_groups(struct group_info *group_info) | |
1296 | { | |
d84f4f99 DH |
1297 | struct cred *new; |
1298 | int ret; | |
1299 | ||
1300 | new = prepare_creds(); | |
1301 | if (!new) | |
1302 | return -ENOMEM; | |
1303 | ||
1304 | ret = set_groups(new, group_info); | |
1305 | if (ret < 0) { | |
1306 | abort_creds(new); | |
1307 | return ret; | |
1308 | } | |
1309 | ||
1310 | return commit_creds(new); | |
b6dff3ec DH |
1311 | } |
1312 | ||
1da177e4 LT |
1313 | EXPORT_SYMBOL(set_current_groups); |
1314 | ||
ae1251ab | 1315 | SYSCALL_DEFINE2(getgroups, int, gidsetsize, gid_t __user *, grouplist) |
1da177e4 | 1316 | { |
86a264ab DH |
1317 | const struct cred *cred = current_cred(); |
1318 | int i; | |
1da177e4 LT |
1319 | |
1320 | if (gidsetsize < 0) | |
1321 | return -EINVAL; | |
1322 | ||
1323 | /* no need to grab task_lock here; it cannot change */ | |
b6dff3ec | 1324 | i = cred->group_info->ngroups; |
1da177e4 LT |
1325 | if (gidsetsize) { |
1326 | if (i > gidsetsize) { | |
1327 | i = -EINVAL; | |
1328 | goto out; | |
1329 | } | |
b6dff3ec | 1330 | if (groups_to_user(grouplist, cred->group_info)) { |
1da177e4 LT |
1331 | i = -EFAULT; |
1332 | goto out; | |
1333 | } | |
1334 | } | |
1335 | out: | |
1da177e4 LT |
1336 | return i; |
1337 | } | |
1338 | ||
1339 | /* | |
1340 | * SMP: Our groups are copy-on-write. We can set them safely | |
1341 | * without another task interfering. | |
1342 | */ | |
1343 | ||
b290ebe2 | 1344 | SYSCALL_DEFINE2(setgroups, int, gidsetsize, gid_t __user *, grouplist) |
1da177e4 LT |
1345 | { |
1346 | struct group_info *group_info; | |
1347 | int retval; | |
1348 | ||
1349 | if (!capable(CAP_SETGID)) | |
1350 | return -EPERM; | |
1351 | if ((unsigned)gidsetsize > NGROUPS_MAX) | |
1352 | return -EINVAL; | |
1353 | ||
1354 | group_info = groups_alloc(gidsetsize); | |
1355 | if (!group_info) | |
1356 | return -ENOMEM; | |
1357 | retval = groups_from_user(group_info, grouplist); | |
1358 | if (retval) { | |
1359 | put_group_info(group_info); | |
1360 | return retval; | |
1361 | } | |
1362 | ||
1363 | retval = set_current_groups(group_info); | |
1364 | put_group_info(group_info); | |
1365 | ||
1366 | return retval; | |
1367 | } | |
1368 | ||
1369 | /* | |
1370 | * Check whether we're fsgid/egid or in the supplemental group.. | |
1371 | */ | |
1372 | int in_group_p(gid_t grp) | |
1373 | { | |
86a264ab | 1374 | const struct cred *cred = current_cred(); |
1da177e4 | 1375 | int retval = 1; |
86a264ab | 1376 | |
b6dff3ec DH |
1377 | if (grp != cred->fsgid) |
1378 | retval = groups_search(cred->group_info, grp); | |
1da177e4 LT |
1379 | return retval; |
1380 | } | |
1381 | ||
1382 | EXPORT_SYMBOL(in_group_p); | |
1383 | ||
1384 | int in_egroup_p(gid_t grp) | |
1385 | { | |
86a264ab | 1386 | const struct cred *cred = current_cred(); |
1da177e4 | 1387 | int retval = 1; |
86a264ab | 1388 | |
b6dff3ec DH |
1389 | if (grp != cred->egid) |
1390 | retval = groups_search(cred->group_info, grp); | |
1da177e4 LT |
1391 | return retval; |
1392 | } | |
1393 | ||
1394 | EXPORT_SYMBOL(in_egroup_p); | |
1395 | ||
1396 | DECLARE_RWSEM(uts_sem); | |
1397 | ||
e48fbb69 | 1398 | SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name) |
1da177e4 LT |
1399 | { |
1400 | int errno = 0; | |
1401 | ||
1402 | down_read(&uts_sem); | |
e9ff3990 | 1403 | if (copy_to_user(name, utsname(), sizeof *name)) |
1da177e4 LT |
1404 | errno = -EFAULT; |
1405 | up_read(&uts_sem); | |
1406 | return errno; | |
1407 | } | |
1408 | ||
5a8a82b1 | 1409 | SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) |
1da177e4 LT |
1410 | { |
1411 | int errno; | |
1412 | char tmp[__NEW_UTS_LEN]; | |
1413 | ||
1414 | if (!capable(CAP_SYS_ADMIN)) | |
1415 | return -EPERM; | |
1416 | if (len < 0 || len > __NEW_UTS_LEN) | |
1417 | return -EINVAL; | |
1418 | down_write(&uts_sem); | |
1419 | errno = -EFAULT; | |
1420 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1421 | struct new_utsname *u = utsname(); |
1422 | ||
1423 | memcpy(u->nodename, tmp, len); | |
1424 | memset(u->nodename + len, 0, sizeof(u->nodename) - len); | |
1da177e4 LT |
1425 | errno = 0; |
1426 | } | |
1427 | up_write(&uts_sem); | |
1428 | return errno; | |
1429 | } | |
1430 | ||
1431 | #ifdef __ARCH_WANT_SYS_GETHOSTNAME | |
1432 | ||
5a8a82b1 | 1433 | SYSCALL_DEFINE2(gethostname, char __user *, name, int, len) |
1da177e4 LT |
1434 | { |
1435 | int i, errno; | |
9679e4dd | 1436 | struct new_utsname *u; |
1da177e4 LT |
1437 | |
1438 | if (len < 0) | |
1439 | return -EINVAL; | |
1440 | down_read(&uts_sem); | |
9679e4dd AM |
1441 | u = utsname(); |
1442 | i = 1 + strlen(u->nodename); | |
1da177e4 LT |
1443 | if (i > len) |
1444 | i = len; | |
1445 | errno = 0; | |
9679e4dd | 1446 | if (copy_to_user(name, u->nodename, i)) |
1da177e4 LT |
1447 | errno = -EFAULT; |
1448 | up_read(&uts_sem); | |
1449 | return errno; | |
1450 | } | |
1451 | ||
1452 | #endif | |
1453 | ||
1454 | /* | |
1455 | * Only setdomainname; getdomainname can be implemented by calling | |
1456 | * uname() | |
1457 | */ | |
5a8a82b1 | 1458 | SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) |
1da177e4 LT |
1459 | { |
1460 | int errno; | |
1461 | char tmp[__NEW_UTS_LEN]; | |
1462 | ||
1463 | if (!capable(CAP_SYS_ADMIN)) | |
1464 | return -EPERM; | |
1465 | if (len < 0 || len > __NEW_UTS_LEN) | |
1466 | return -EINVAL; | |
1467 | ||
1468 | down_write(&uts_sem); | |
1469 | errno = -EFAULT; | |
1470 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1471 | struct new_utsname *u = utsname(); |
1472 | ||
1473 | memcpy(u->domainname, tmp, len); | |
1474 | memset(u->domainname + len, 0, sizeof(u->domainname) - len); | |
1da177e4 LT |
1475 | errno = 0; |
1476 | } | |
1477 | up_write(&uts_sem); | |
1478 | return errno; | |
1479 | } | |
1480 | ||
e48fbb69 | 1481 | SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1da177e4 LT |
1482 | { |
1483 | if (resource >= RLIM_NLIMITS) | |
1484 | return -EINVAL; | |
1485 | else { | |
1486 | struct rlimit value; | |
1487 | task_lock(current->group_leader); | |
1488 | value = current->signal->rlim[resource]; | |
1489 | task_unlock(current->group_leader); | |
1490 | return copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; | |
1491 | } | |
1492 | } | |
1493 | ||
1494 | #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT | |
1495 | ||
1496 | /* | |
1497 | * Back compatibility for getrlimit. Needed for some apps. | |
1498 | */ | |
1499 | ||
e48fbb69 HC |
1500 | SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, |
1501 | struct rlimit __user *, rlim) | |
1da177e4 LT |
1502 | { |
1503 | struct rlimit x; | |
1504 | if (resource >= RLIM_NLIMITS) | |
1505 | return -EINVAL; | |
1506 | ||
1507 | task_lock(current->group_leader); | |
1508 | x = current->signal->rlim[resource]; | |
1509 | task_unlock(current->group_leader); | |
756184b7 | 1510 | if (x.rlim_cur > 0x7FFFFFFF) |
1da177e4 | 1511 | x.rlim_cur = 0x7FFFFFFF; |
756184b7 | 1512 | if (x.rlim_max > 0x7FFFFFFF) |
1da177e4 LT |
1513 | x.rlim_max = 0x7FFFFFFF; |
1514 | return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0; | |
1515 | } | |
1516 | ||
1517 | #endif | |
1518 | ||
e48fbb69 | 1519 | SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1da177e4 LT |
1520 | { |
1521 | struct rlimit new_rlim, *old_rlim; | |
1522 | int retval; | |
1523 | ||
1524 | if (resource >= RLIM_NLIMITS) | |
1525 | return -EINVAL; | |
ec9e16ba | 1526 | if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) |
1da177e4 | 1527 | return -EFAULT; |
1da177e4 LT |
1528 | old_rlim = current->signal->rlim + resource; |
1529 | if ((new_rlim.rlim_max > old_rlim->rlim_max) && | |
1530 | !capable(CAP_SYS_RESOURCE)) | |
1531 | return -EPERM; | |
0c2d64fb AT |
1532 | |
1533 | if (resource == RLIMIT_NOFILE) { | |
1534 | if (new_rlim.rlim_max == RLIM_INFINITY) | |
1535 | new_rlim.rlim_max = sysctl_nr_open; | |
1536 | if (new_rlim.rlim_cur == RLIM_INFINITY) | |
1537 | new_rlim.rlim_cur = sysctl_nr_open; | |
1538 | if (new_rlim.rlim_max > sysctl_nr_open) | |
1539 | return -EPERM; | |
1540 | } | |
1541 | ||
1542 | if (new_rlim.rlim_cur > new_rlim.rlim_max) | |
1543 | return -EINVAL; | |
1da177e4 LT |
1544 | |
1545 | retval = security_task_setrlimit(resource, &new_rlim); | |
1546 | if (retval) | |
1547 | return retval; | |
1548 | ||
9926e4c7 TA |
1549 | if (resource == RLIMIT_CPU && new_rlim.rlim_cur == 0) { |
1550 | /* | |
1551 | * The caller is asking for an immediate RLIMIT_CPU | |
1552 | * expiry. But we use the zero value to mean "it was | |
1553 | * never set". So let's cheat and make it one second | |
1554 | * instead | |
1555 | */ | |
1556 | new_rlim.rlim_cur = 1; | |
1557 | } | |
1558 | ||
1da177e4 LT |
1559 | task_lock(current->group_leader); |
1560 | *old_rlim = new_rlim; | |
1561 | task_unlock(current->group_leader); | |
1562 | ||
ec9e16ba AM |
1563 | if (resource != RLIMIT_CPU) |
1564 | goto out; | |
d3561f78 AM |
1565 | |
1566 | /* | |
1567 | * RLIMIT_CPU handling. Note that the kernel fails to return an error | |
1568 | * code if it rejected the user's attempt to set RLIMIT_CPU. This is a | |
1569 | * very long-standing error, and fixing it now risks breakage of | |
1570 | * applications, so we live with it | |
1571 | */ | |
ec9e16ba AM |
1572 | if (new_rlim.rlim_cur == RLIM_INFINITY) |
1573 | goto out; | |
1574 | ||
f06febc9 | 1575 | update_rlimit_cpu(new_rlim.rlim_cur); |
ec9e16ba | 1576 | out: |
1da177e4 LT |
1577 | return 0; |
1578 | } | |
1579 | ||
1580 | /* | |
1581 | * It would make sense to put struct rusage in the task_struct, | |
1582 | * except that would make the task_struct be *really big*. After | |
1583 | * task_struct gets moved into malloc'ed memory, it would | |
1584 | * make sense to do this. It will make moving the rest of the information | |
1585 | * a lot simpler! (Which we're not doing right now because we're not | |
1586 | * measuring them yet). | |
1587 | * | |
1da177e4 LT |
1588 | * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
1589 | * races with threads incrementing their own counters. But since word | |
1590 | * reads are atomic, we either get new values or old values and we don't | |
1591 | * care which for the sums. We always take the siglock to protect reading | |
1592 | * the c* fields from p->signal from races with exit.c updating those | |
1593 | * fields when reaping, so a sample either gets all the additions of a | |
1594 | * given child after it's reaped, or none so this sample is before reaping. | |
2dd0ebcd | 1595 | * |
de047c1b RT |
1596 | * Locking: |
1597 | * We need to take the siglock for CHILDEREN, SELF and BOTH | |
1598 | * for the cases current multithreaded, non-current single threaded | |
1599 | * non-current multithreaded. Thread traversal is now safe with | |
1600 | * the siglock held. | |
1601 | * Strictly speaking, we donot need to take the siglock if we are current and | |
1602 | * single threaded, as no one else can take our signal_struct away, no one | |
1603 | * else can reap the children to update signal->c* counters, and no one else | |
1604 | * can race with the signal-> fields. If we do not take any lock, the | |
1605 | * signal-> fields could be read out of order while another thread was just | |
1606 | * exiting. So we should place a read memory barrier when we avoid the lock. | |
1607 | * On the writer side, write memory barrier is implied in __exit_signal | |
1608 | * as __exit_signal releases the siglock spinlock after updating the signal-> | |
1609 | * fields. But we don't do this yet to keep things simple. | |
2dd0ebcd | 1610 | * |
1da177e4 LT |
1611 | */ |
1612 | ||
f06febc9 | 1613 | static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) |
679c9cd4 | 1614 | { |
679c9cd4 SK |
1615 | r->ru_nvcsw += t->nvcsw; |
1616 | r->ru_nivcsw += t->nivcsw; | |
1617 | r->ru_minflt += t->min_flt; | |
1618 | r->ru_majflt += t->maj_flt; | |
1619 | r->ru_inblock += task_io_get_inblock(t); | |
1620 | r->ru_oublock += task_io_get_oublock(t); | |
1621 | } | |
1622 | ||
1da177e4 LT |
1623 | static void k_getrusage(struct task_struct *p, int who, struct rusage *r) |
1624 | { | |
1625 | struct task_struct *t; | |
1626 | unsigned long flags; | |
1627 | cputime_t utime, stime; | |
f06febc9 | 1628 | struct task_cputime cputime; |
1da177e4 LT |
1629 | |
1630 | memset((char *) r, 0, sizeof *r); | |
2dd0ebcd | 1631 | utime = stime = cputime_zero; |
1da177e4 | 1632 | |
679c9cd4 | 1633 | if (who == RUSAGE_THREAD) { |
8916edef KM |
1634 | utime = task_utime(current); |
1635 | stime = task_stime(current); | |
f06febc9 | 1636 | accumulate_thread_rusage(p, r); |
679c9cd4 SK |
1637 | goto out; |
1638 | } | |
1639 | ||
d6cf723a | 1640 | if (!lock_task_sighand(p, &flags)) |
de047c1b | 1641 | return; |
0f59cc4a | 1642 | |
1da177e4 | 1643 | switch (who) { |
0f59cc4a | 1644 | case RUSAGE_BOTH: |
1da177e4 | 1645 | case RUSAGE_CHILDREN: |
1da177e4 LT |
1646 | utime = p->signal->cutime; |
1647 | stime = p->signal->cstime; | |
1648 | r->ru_nvcsw = p->signal->cnvcsw; | |
1649 | r->ru_nivcsw = p->signal->cnivcsw; | |
1650 | r->ru_minflt = p->signal->cmin_flt; | |
1651 | r->ru_majflt = p->signal->cmaj_flt; | |
6eaeeaba ED |
1652 | r->ru_inblock = p->signal->cinblock; |
1653 | r->ru_oublock = p->signal->coublock; | |
0f59cc4a ON |
1654 | |
1655 | if (who == RUSAGE_CHILDREN) | |
1656 | break; | |
1657 | ||
1da177e4 | 1658 | case RUSAGE_SELF: |
f06febc9 FM |
1659 | thread_group_cputime(p, &cputime); |
1660 | utime = cputime_add(utime, cputime.utime); | |
1661 | stime = cputime_add(stime, cputime.stime); | |
1da177e4 LT |
1662 | r->ru_nvcsw += p->signal->nvcsw; |
1663 | r->ru_nivcsw += p->signal->nivcsw; | |
1664 | r->ru_minflt += p->signal->min_flt; | |
1665 | r->ru_majflt += p->signal->maj_flt; | |
6eaeeaba ED |
1666 | r->ru_inblock += p->signal->inblock; |
1667 | r->ru_oublock += p->signal->oublock; | |
1da177e4 LT |
1668 | t = p; |
1669 | do { | |
f06febc9 | 1670 | accumulate_thread_rusage(t, r); |
1da177e4 LT |
1671 | t = next_thread(t); |
1672 | } while (t != p); | |
1da177e4 | 1673 | break; |
0f59cc4a | 1674 | |
1da177e4 LT |
1675 | default: |
1676 | BUG(); | |
1677 | } | |
de047c1b | 1678 | unlock_task_sighand(p, &flags); |
de047c1b | 1679 | |
679c9cd4 | 1680 | out: |
0f59cc4a ON |
1681 | cputime_to_timeval(utime, &r->ru_utime); |
1682 | cputime_to_timeval(stime, &r->ru_stime); | |
1da177e4 LT |
1683 | } |
1684 | ||
1685 | int getrusage(struct task_struct *p, int who, struct rusage __user *ru) | |
1686 | { | |
1687 | struct rusage r; | |
1da177e4 | 1688 | k_getrusage(p, who, &r); |
1da177e4 LT |
1689 | return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
1690 | } | |
1691 | ||
e48fbb69 | 1692 | SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) |
1da177e4 | 1693 | { |
679c9cd4 SK |
1694 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
1695 | who != RUSAGE_THREAD) | |
1da177e4 LT |
1696 | return -EINVAL; |
1697 | return getrusage(current, who, ru); | |
1698 | } | |
1699 | ||
e48fbb69 | 1700 | SYSCALL_DEFINE1(umask, int, mask) |
1da177e4 LT |
1701 | { |
1702 | mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); | |
1703 | return mask; | |
1704 | } | |
3b7391de | 1705 | |
c4ea37c2 HC |
1706 | SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, |
1707 | unsigned long, arg4, unsigned long, arg5) | |
1da177e4 | 1708 | { |
b6dff3ec DH |
1709 | struct task_struct *me = current; |
1710 | unsigned char comm[sizeof(me->comm)]; | |
1711 | long error; | |
1da177e4 | 1712 | |
d84f4f99 DH |
1713 | error = security_task_prctl(option, arg2, arg3, arg4, arg5); |
1714 | if (error != -ENOSYS) | |
1da177e4 LT |
1715 | return error; |
1716 | ||
d84f4f99 | 1717 | error = 0; |
1da177e4 LT |
1718 | switch (option) { |
1719 | case PR_SET_PDEATHSIG: | |
0730ded5 | 1720 | if (!valid_signal(arg2)) { |
1da177e4 LT |
1721 | error = -EINVAL; |
1722 | break; | |
1723 | } | |
b6dff3ec DH |
1724 | me->pdeath_signal = arg2; |
1725 | error = 0; | |
1da177e4 LT |
1726 | break; |
1727 | case PR_GET_PDEATHSIG: | |
b6dff3ec | 1728 | error = put_user(me->pdeath_signal, (int __user *)arg2); |
1da177e4 LT |
1729 | break; |
1730 | case PR_GET_DUMPABLE: | |
b6dff3ec | 1731 | error = get_dumpable(me->mm); |
1da177e4 LT |
1732 | break; |
1733 | case PR_SET_DUMPABLE: | |
abf75a50 | 1734 | if (arg2 < 0 || arg2 > 1) { |
1da177e4 LT |
1735 | error = -EINVAL; |
1736 | break; | |
1737 | } | |
b6dff3ec DH |
1738 | set_dumpable(me->mm, arg2); |
1739 | error = 0; | |
1da177e4 LT |
1740 | break; |
1741 | ||
1742 | case PR_SET_UNALIGN: | |
b6dff3ec | 1743 | error = SET_UNALIGN_CTL(me, arg2); |
1da177e4 LT |
1744 | break; |
1745 | case PR_GET_UNALIGN: | |
b6dff3ec | 1746 | error = GET_UNALIGN_CTL(me, arg2); |
1da177e4 LT |
1747 | break; |
1748 | case PR_SET_FPEMU: | |
b6dff3ec | 1749 | error = SET_FPEMU_CTL(me, arg2); |
1da177e4 LT |
1750 | break; |
1751 | case PR_GET_FPEMU: | |
b6dff3ec | 1752 | error = GET_FPEMU_CTL(me, arg2); |
1da177e4 LT |
1753 | break; |
1754 | case PR_SET_FPEXC: | |
b6dff3ec | 1755 | error = SET_FPEXC_CTL(me, arg2); |
1da177e4 LT |
1756 | break; |
1757 | case PR_GET_FPEXC: | |
b6dff3ec | 1758 | error = GET_FPEXC_CTL(me, arg2); |
1da177e4 LT |
1759 | break; |
1760 | case PR_GET_TIMING: | |
1761 | error = PR_TIMING_STATISTICAL; | |
1762 | break; | |
1763 | case PR_SET_TIMING: | |
7b26655f | 1764 | if (arg2 != PR_TIMING_STATISTICAL) |
1da177e4 | 1765 | error = -EINVAL; |
b6dff3ec DH |
1766 | else |
1767 | error = 0; | |
1da177e4 LT |
1768 | break; |
1769 | ||
b6dff3ec DH |
1770 | case PR_SET_NAME: |
1771 | comm[sizeof(me->comm)-1] = 0; | |
1772 | if (strncpy_from_user(comm, (char __user *)arg2, | |
1773 | sizeof(me->comm) - 1) < 0) | |
1da177e4 | 1774 | return -EFAULT; |
b6dff3ec | 1775 | set_task_comm(me, comm); |
1da177e4 | 1776 | return 0; |
b6dff3ec DH |
1777 | case PR_GET_NAME: |
1778 | get_task_comm(comm, me); | |
1779 | if (copy_to_user((char __user *)arg2, comm, | |
1780 | sizeof(comm))) | |
1da177e4 LT |
1781 | return -EFAULT; |
1782 | return 0; | |
651d765d | 1783 | case PR_GET_ENDIAN: |
b6dff3ec | 1784 | error = GET_ENDIAN(me, arg2); |
651d765d AB |
1785 | break; |
1786 | case PR_SET_ENDIAN: | |
b6dff3ec | 1787 | error = SET_ENDIAN(me, arg2); |
651d765d AB |
1788 | break; |
1789 | ||
1d9d02fe AA |
1790 | case PR_GET_SECCOMP: |
1791 | error = prctl_get_seccomp(); | |
1792 | break; | |
1793 | case PR_SET_SECCOMP: | |
1794 | error = prctl_set_seccomp(arg2); | |
1795 | break; | |
8fb402bc EB |
1796 | case PR_GET_TSC: |
1797 | error = GET_TSC_CTL(arg2); | |
1798 | break; | |
1799 | case PR_SET_TSC: | |
1800 | error = SET_TSC_CTL(arg2); | |
1801 | break; | |
6976675d AV |
1802 | case PR_GET_TIMERSLACK: |
1803 | error = current->timer_slack_ns; | |
1804 | break; | |
1805 | case PR_SET_TIMERSLACK: | |
1806 | if (arg2 <= 0) | |
1807 | current->timer_slack_ns = | |
1808 | current->default_timer_slack_ns; | |
1809 | else | |
1810 | current->timer_slack_ns = arg2; | |
b6dff3ec | 1811 | error = 0; |
6976675d | 1812 | break; |
1da177e4 LT |
1813 | default: |
1814 | error = -EINVAL; | |
1815 | break; | |
1816 | } | |
1817 | return error; | |
1818 | } | |
3cfc348b AK |
1819 | |
1820 | asmlinkage long sys_getcpu(unsigned __user *cpup, unsigned __user *nodep, | |
4307d1e5 | 1821 | struct getcpu_cache __user *unused) |
3cfc348b AK |
1822 | { |
1823 | int err = 0; | |
1824 | int cpu = raw_smp_processor_id(); | |
1825 | if (cpup) | |
1826 | err |= put_user(cpu, cpup); | |
1827 | if (nodep) | |
1828 | err |= put_user(cpu_to_node(cpu), nodep); | |
3cfc348b AK |
1829 | return err ? -EFAULT : 0; |
1830 | } | |
10a0a8d4 JF |
1831 | |
1832 | char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff"; | |
1833 | ||
1834 | static void argv_cleanup(char **argv, char **envp) | |
1835 | { | |
1836 | argv_free(argv); | |
1837 | } | |
1838 | ||
1839 | /** | |
1840 | * orderly_poweroff - Trigger an orderly system poweroff | |
1841 | * @force: force poweroff if command execution fails | |
1842 | * | |
1843 | * This may be called from any context to trigger a system shutdown. | |
1844 | * If the orderly shutdown fails, it will force an immediate shutdown. | |
1845 | */ | |
1846 | int orderly_poweroff(bool force) | |
1847 | { | |
1848 | int argc; | |
1849 | char **argv = argv_split(GFP_ATOMIC, poweroff_cmd, &argc); | |
1850 | static char *envp[] = { | |
1851 | "HOME=/", | |
1852 | "PATH=/sbin:/bin:/usr/sbin:/usr/bin", | |
1853 | NULL | |
1854 | }; | |
1855 | int ret = -ENOMEM; | |
1856 | struct subprocess_info *info; | |
1857 | ||
1858 | if (argv == NULL) { | |
1859 | printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n", | |
1860 | __func__, poweroff_cmd); | |
1861 | goto out; | |
1862 | } | |
1863 | ||
ac331d15 | 1864 | info = call_usermodehelper_setup(argv[0], argv, envp, GFP_ATOMIC); |
10a0a8d4 JF |
1865 | if (info == NULL) { |
1866 | argv_free(argv); | |
1867 | goto out; | |
1868 | } | |
1869 | ||
1870 | call_usermodehelper_setcleanup(info, argv_cleanup); | |
1871 | ||
86313c48 | 1872 | ret = call_usermodehelper_exec(info, UMH_NO_WAIT); |
10a0a8d4 JF |
1873 | |
1874 | out: | |
1875 | if (ret && force) { | |
1876 | printk(KERN_WARNING "Failed to start orderly shutdown: " | |
1877 | "forcing the issue\n"); | |
1878 | ||
1879 | /* I guess this should try to kick off some daemon to | |
1880 | sync and poweroff asap. Or not even bother syncing | |
1881 | if we're doing an emergency shutdown? */ | |
1882 | emergency_sync(); | |
1883 | kernel_power_off(); | |
1884 | } | |
1885 | ||
1886 | return ret; | |
1887 | } | |
1888 | EXPORT_SYMBOL_GPL(orderly_poweroff); |