Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/kernel/sys.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | */ | |
6 | ||
1da177e4 LT |
7 | #include <linux/module.h> |
8 | #include <linux/mm.h> | |
9 | #include <linux/utsname.h> | |
10 | #include <linux/mman.h> | |
11 | #include <linux/smp_lock.h> | |
12 | #include <linux/notifier.h> | |
13 | #include <linux/reboot.h> | |
14 | #include <linux/prctl.h> | |
1da177e4 LT |
15 | #include <linux/highuid.h> |
16 | #include <linux/fs.h> | |
3e88c553 | 17 | #include <linux/resource.h> |
dc009d92 EB |
18 | #include <linux/kernel.h> |
19 | #include <linux/kexec.h> | |
1da177e4 | 20 | #include <linux/workqueue.h> |
c59ede7b | 21 | #include <linux/capability.h> |
1da177e4 LT |
22 | #include <linux/device.h> |
23 | #include <linux/key.h> | |
24 | #include <linux/times.h> | |
25 | #include <linux/posix-timers.h> | |
26 | #include <linux/security.h> | |
27 | #include <linux/dcookies.h> | |
28 | #include <linux/suspend.h> | |
29 | #include <linux/tty.h> | |
7ed20e1a | 30 | #include <linux/signal.h> |
9f46080c | 31 | #include <linux/cn_proc.h> |
3cfc348b | 32 | #include <linux/getcpu.h> |
6eaeeaba | 33 | #include <linux/task_io_accounting_ops.h> |
1d9d02fe | 34 | #include <linux/seccomp.h> |
4047727e | 35 | #include <linux/cpu.h> |
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]; | |
3d26dcf7 | 363 | int ret = 0; |
1da177e4 LT |
364 | |
365 | /* We only trust the superuser with rebooting the system. */ | |
366 | if (!capable(CAP_SYS_BOOT)) | |
367 | return -EPERM; | |
368 | ||
369 | /* For safety, we require "magic" arguments. */ | |
370 | if (magic1 != LINUX_REBOOT_MAGIC1 || | |
371 | (magic2 != LINUX_REBOOT_MAGIC2 && | |
372 | magic2 != LINUX_REBOOT_MAGIC2A && | |
373 | magic2 != LINUX_REBOOT_MAGIC2B && | |
374 | magic2 != LINUX_REBOOT_MAGIC2C)) | |
375 | return -EINVAL; | |
376 | ||
5e38291d EB |
377 | /* Instead of trying to make the power_off code look like |
378 | * halt when pm_power_off is not set do it the easy way. | |
379 | */ | |
380 | if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off) | |
381 | cmd = LINUX_REBOOT_CMD_HALT; | |
382 | ||
1da177e4 LT |
383 | lock_kernel(); |
384 | switch (cmd) { | |
385 | case LINUX_REBOOT_CMD_RESTART: | |
4a00ea1e | 386 | kernel_restart(NULL); |
1da177e4 LT |
387 | break; |
388 | ||
389 | case LINUX_REBOOT_CMD_CAD_ON: | |
390 | C_A_D = 1; | |
391 | break; | |
392 | ||
393 | case LINUX_REBOOT_CMD_CAD_OFF: | |
394 | C_A_D = 0; | |
395 | break; | |
396 | ||
397 | case LINUX_REBOOT_CMD_HALT: | |
4a00ea1e | 398 | kernel_halt(); |
1da177e4 LT |
399 | unlock_kernel(); |
400 | do_exit(0); | |
3d26dcf7 | 401 | panic("cannot halt"); |
1da177e4 LT |
402 | |
403 | case LINUX_REBOOT_CMD_POWER_OFF: | |
4a00ea1e | 404 | kernel_power_off(); |
1da177e4 LT |
405 | unlock_kernel(); |
406 | do_exit(0); | |
407 | break; | |
408 | ||
409 | case LINUX_REBOOT_CMD_RESTART2: | |
410 | if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) { | |
411 | unlock_kernel(); | |
412 | return -EFAULT; | |
413 | } | |
414 | buffer[sizeof(buffer) - 1] = '\0'; | |
415 | ||
4a00ea1e | 416 | kernel_restart(buffer); |
1da177e4 LT |
417 | break; |
418 | ||
3ab83521 | 419 | #ifdef CONFIG_KEXEC |
dc009d92 | 420 | case LINUX_REBOOT_CMD_KEXEC: |
3d26dcf7 AK |
421 | ret = kernel_kexec(); |
422 | break; | |
3ab83521 | 423 | #endif |
4a00ea1e | 424 | |
b0cb1a19 | 425 | #ifdef CONFIG_HIBERNATION |
1da177e4 | 426 | case LINUX_REBOOT_CMD_SW_SUSPEND: |
3d26dcf7 AK |
427 | ret = hibernate(); |
428 | break; | |
1da177e4 LT |
429 | #endif |
430 | ||
431 | default: | |
3d26dcf7 AK |
432 | ret = -EINVAL; |
433 | break; | |
1da177e4 LT |
434 | } |
435 | unlock_kernel(); | |
3d26dcf7 | 436 | return ret; |
1da177e4 LT |
437 | } |
438 | ||
65f27f38 | 439 | static void deferred_cad(struct work_struct *dummy) |
1da177e4 | 440 | { |
abcd9e51 | 441 | kernel_restart(NULL); |
1da177e4 LT |
442 | } |
443 | ||
444 | /* | |
445 | * This function gets called by ctrl-alt-del - ie the keyboard interrupt. | |
446 | * As it's called within an interrupt, it may NOT sync: the only choice | |
447 | * is whether to reboot at once, or just ignore the ctrl-alt-del. | |
448 | */ | |
449 | void ctrl_alt_del(void) | |
450 | { | |
65f27f38 | 451 | static DECLARE_WORK(cad_work, deferred_cad); |
1da177e4 LT |
452 | |
453 | if (C_A_D) | |
454 | schedule_work(&cad_work); | |
455 | else | |
9ec52099 | 456 | kill_cad_pid(SIGINT, 1); |
1da177e4 LT |
457 | } |
458 | ||
1da177e4 LT |
459 | /* |
460 | * Unprivileged users may change the real gid to the effective gid | |
461 | * or vice versa. (BSD-style) | |
462 | * | |
463 | * If you set the real gid at all, or set the effective gid to a value not | |
464 | * equal to the real gid, then the saved gid is set to the new effective gid. | |
465 | * | |
466 | * This makes it possible for a setgid program to completely drop its | |
467 | * privileges, which is often a useful assertion to make when you are doing | |
468 | * a security audit over a program. | |
469 | * | |
470 | * The general idea is that a program which uses just setregid() will be | |
471 | * 100% compatible with BSD. A program which uses just setgid() will be | |
472 | * 100% compatible with POSIX with saved IDs. | |
473 | * | |
474 | * SMP: There are not races, the GIDs are checked only by filesystem | |
475 | * operations (as far as semantic preservation is concerned). | |
476 | */ | |
ae1251ab | 477 | SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) |
1da177e4 | 478 | { |
d84f4f99 DH |
479 | const struct cred *old; |
480 | struct cred *new; | |
1da177e4 LT |
481 | int retval; |
482 | ||
d84f4f99 DH |
483 | new = prepare_creds(); |
484 | if (!new) | |
485 | return -ENOMEM; | |
486 | old = current_cred(); | |
487 | ||
1da177e4 LT |
488 | retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE); |
489 | if (retval) | |
d84f4f99 | 490 | goto error; |
1da177e4 | 491 | |
d84f4f99 | 492 | retval = -EPERM; |
1da177e4 | 493 | if (rgid != (gid_t) -1) { |
d84f4f99 DH |
494 | if (old->gid == rgid || |
495 | old->egid == rgid || | |
1da177e4 | 496 | capable(CAP_SETGID)) |
d84f4f99 | 497 | new->gid = rgid; |
1da177e4 | 498 | else |
d84f4f99 | 499 | goto error; |
1da177e4 LT |
500 | } |
501 | if (egid != (gid_t) -1) { | |
d84f4f99 DH |
502 | if (old->gid == egid || |
503 | old->egid == egid || | |
504 | old->sgid == egid || | |
1da177e4 | 505 | capable(CAP_SETGID)) |
d84f4f99 | 506 | new->egid = egid; |
756184b7 | 507 | else |
d84f4f99 | 508 | goto error; |
1da177e4 | 509 | } |
d84f4f99 | 510 | |
1da177e4 | 511 | if (rgid != (gid_t) -1 || |
d84f4f99 DH |
512 | (egid != (gid_t) -1 && egid != old->gid)) |
513 | new->sgid = new->egid; | |
514 | new->fsgid = new->egid; | |
515 | ||
516 | return commit_creds(new); | |
517 | ||
518 | error: | |
519 | abort_creds(new); | |
520 | return retval; | |
1da177e4 LT |
521 | } |
522 | ||
523 | /* | |
524 | * setgid() is implemented like SysV w/ SAVED_IDS | |
525 | * | |
526 | * SMP: Same implicit races as above. | |
527 | */ | |
ae1251ab | 528 | SYSCALL_DEFINE1(setgid, gid_t, gid) |
1da177e4 | 529 | { |
d84f4f99 DH |
530 | const struct cred *old; |
531 | struct cred *new; | |
1da177e4 LT |
532 | int retval; |
533 | ||
d84f4f99 DH |
534 | new = prepare_creds(); |
535 | if (!new) | |
536 | return -ENOMEM; | |
537 | old = current_cred(); | |
538 | ||
1da177e4 LT |
539 | retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID); |
540 | if (retval) | |
d84f4f99 | 541 | goto error; |
1da177e4 | 542 | |
d84f4f99 DH |
543 | retval = -EPERM; |
544 | if (capable(CAP_SETGID)) | |
545 | new->gid = new->egid = new->sgid = new->fsgid = gid; | |
546 | else if (gid == old->gid || gid == old->sgid) | |
547 | new->egid = new->fsgid = gid; | |
1da177e4 | 548 | else |
d84f4f99 | 549 | goto error; |
1da177e4 | 550 | |
d84f4f99 DH |
551 | return commit_creds(new); |
552 | ||
553 | error: | |
554 | abort_creds(new); | |
555 | return retval; | |
1da177e4 | 556 | } |
54e99124 | 557 | |
d84f4f99 DH |
558 | /* |
559 | * change the user struct in a credentials set to match the new UID | |
560 | */ | |
561 | static int set_user(struct cred *new) | |
1da177e4 LT |
562 | { |
563 | struct user_struct *new_user; | |
564 | ||
18b6e041 | 565 | new_user = alloc_uid(current_user_ns(), new->uid); |
1da177e4 LT |
566 | if (!new_user) |
567 | return -EAGAIN; | |
568 | ||
54e99124 DG |
569 | if (!task_can_switch_user(new_user, current)) { |
570 | free_uid(new_user); | |
571 | return -EINVAL; | |
572 | } | |
573 | ||
1da177e4 LT |
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 | ||
54e99124 DG |
634 | if (new->uid != old->uid) { |
635 | retval = set_user(new); | |
636 | if (retval < 0) | |
637 | goto error; | |
638 | } | |
1da177e4 | 639 | if (ruid != (uid_t) -1 || |
d84f4f99 DH |
640 | (euid != (uid_t) -1 && euid != old->uid)) |
641 | new->suid = new->euid; | |
642 | new->fsuid = new->euid; | |
1da177e4 | 643 | |
d84f4f99 DH |
644 | retval = security_task_fix_setuid(new, old, LSM_SETID_RE); |
645 | if (retval < 0) | |
646 | goto error; | |
1da177e4 | 647 | |
d84f4f99 | 648 | return commit_creds(new); |
1da177e4 | 649 | |
d84f4f99 DH |
650 | error: |
651 | abort_creds(new); | |
652 | return retval; | |
653 | } | |
1da177e4 LT |
654 | |
655 | /* | |
656 | * setuid() is implemented like SysV with SAVED_IDS | |
657 | * | |
658 | * Note that SAVED_ID's is deficient in that a setuid root program | |
659 | * like sendmail, for example, cannot set its uid to be a normal | |
660 | * user and then switch back, because if you're root, setuid() sets | |
661 | * the saved uid too. If you don't like this, blame the bright people | |
662 | * in the POSIX committee and/or USG. Note that the BSD-style setreuid() | |
663 | * will allow a root program to temporarily drop privileges and be able to | |
664 | * regain them by swapping the real and effective uid. | |
665 | */ | |
ae1251ab | 666 | SYSCALL_DEFINE1(setuid, uid_t, uid) |
1da177e4 | 667 | { |
d84f4f99 DH |
668 | const struct cred *old; |
669 | struct cred *new; | |
1da177e4 LT |
670 | int retval; |
671 | ||
d84f4f99 DH |
672 | new = prepare_creds(); |
673 | if (!new) | |
674 | return -ENOMEM; | |
675 | old = current_cred(); | |
676 | ||
1da177e4 LT |
677 | retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID); |
678 | if (retval) | |
d84f4f99 | 679 | goto error; |
1da177e4 | 680 | |
d84f4f99 | 681 | retval = -EPERM; |
1da177e4 | 682 | if (capable(CAP_SETUID)) { |
d84f4f99 | 683 | new->suid = new->uid = uid; |
54e99124 DG |
684 | if (uid != old->uid) { |
685 | retval = set_user(new); | |
686 | if (retval < 0) | |
687 | goto error; | |
d84f4f99 DH |
688 | } |
689 | } else if (uid != old->uid && uid != new->suid) { | |
690 | goto error; | |
1da177e4 | 691 | } |
1da177e4 | 692 | |
d84f4f99 DH |
693 | new->fsuid = new->euid = uid; |
694 | ||
695 | retval = security_task_fix_setuid(new, old, LSM_SETID_ID); | |
696 | if (retval < 0) | |
697 | goto error; | |
698 | ||
699 | return commit_creds(new); | |
1da177e4 | 700 | |
d84f4f99 DH |
701 | error: |
702 | abort_creds(new); | |
703 | return retval; | |
1da177e4 LT |
704 | } |
705 | ||
706 | ||
707 | /* | |
708 | * This function implements a generic ability to update ruid, euid, | |
709 | * and suid. This allows you to implement the 4.4 compatible seteuid(). | |
710 | */ | |
ae1251ab | 711 | SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) |
1da177e4 | 712 | { |
d84f4f99 DH |
713 | const struct cred *old; |
714 | struct cred *new; | |
1da177e4 LT |
715 | int retval; |
716 | ||
d84f4f99 DH |
717 | new = prepare_creds(); |
718 | if (!new) | |
719 | return -ENOMEM; | |
720 | ||
1da177e4 LT |
721 | retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES); |
722 | if (retval) | |
d84f4f99 DH |
723 | goto error; |
724 | old = current_cred(); | |
1da177e4 | 725 | |
d84f4f99 | 726 | retval = -EPERM; |
1da177e4 | 727 | if (!capable(CAP_SETUID)) { |
d84f4f99 DH |
728 | if (ruid != (uid_t) -1 && ruid != old->uid && |
729 | ruid != old->euid && ruid != old->suid) | |
730 | goto error; | |
731 | if (euid != (uid_t) -1 && euid != old->uid && | |
732 | euid != old->euid && euid != old->suid) | |
733 | goto error; | |
734 | if (suid != (uid_t) -1 && suid != old->uid && | |
735 | suid != old->euid && suid != old->suid) | |
736 | goto error; | |
1da177e4 | 737 | } |
d84f4f99 | 738 | |
1da177e4 | 739 | if (ruid != (uid_t) -1) { |
d84f4f99 | 740 | new->uid = ruid; |
54e99124 DG |
741 | if (ruid != old->uid) { |
742 | retval = set_user(new); | |
743 | if (retval < 0) | |
744 | goto error; | |
745 | } | |
1da177e4 | 746 | } |
d84f4f99 DH |
747 | if (euid != (uid_t) -1) |
748 | new->euid = euid; | |
1da177e4 | 749 | if (suid != (uid_t) -1) |
d84f4f99 DH |
750 | new->suid = suid; |
751 | new->fsuid = new->euid; | |
1da177e4 | 752 | |
d84f4f99 DH |
753 | retval = security_task_fix_setuid(new, old, LSM_SETID_RES); |
754 | if (retval < 0) | |
755 | goto error; | |
1da177e4 | 756 | |
d84f4f99 DH |
757 | return commit_creds(new); |
758 | ||
759 | error: | |
760 | abort_creds(new); | |
761 | return retval; | |
1da177e4 LT |
762 | } |
763 | ||
dbf040d9 | 764 | SYSCALL_DEFINE3(getresuid, uid_t __user *, ruid, uid_t __user *, euid, uid_t __user *, suid) |
1da177e4 | 765 | { |
86a264ab | 766 | const struct cred *cred = current_cred(); |
1da177e4 LT |
767 | int retval; |
768 | ||
86a264ab DH |
769 | if (!(retval = put_user(cred->uid, ruid)) && |
770 | !(retval = put_user(cred->euid, euid))) | |
b6dff3ec | 771 | retval = put_user(cred->suid, suid); |
1da177e4 LT |
772 | |
773 | return retval; | |
774 | } | |
775 | ||
776 | /* | |
777 | * Same as above, but for rgid, egid, sgid. | |
778 | */ | |
ae1251ab | 779 | SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) |
1da177e4 | 780 | { |
d84f4f99 DH |
781 | const struct cred *old; |
782 | struct cred *new; | |
1da177e4 LT |
783 | int retval; |
784 | ||
d84f4f99 DH |
785 | new = prepare_creds(); |
786 | if (!new) | |
787 | return -ENOMEM; | |
788 | old = current_cred(); | |
789 | ||
1da177e4 LT |
790 | retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES); |
791 | if (retval) | |
d84f4f99 | 792 | goto error; |
1da177e4 | 793 | |
d84f4f99 | 794 | retval = -EPERM; |
1da177e4 | 795 | if (!capable(CAP_SETGID)) { |
d84f4f99 DH |
796 | if (rgid != (gid_t) -1 && rgid != old->gid && |
797 | rgid != old->egid && rgid != old->sgid) | |
798 | goto error; | |
799 | if (egid != (gid_t) -1 && egid != old->gid && | |
800 | egid != old->egid && egid != old->sgid) | |
801 | goto error; | |
802 | if (sgid != (gid_t) -1 && sgid != old->gid && | |
803 | sgid != old->egid && sgid != old->sgid) | |
804 | goto error; | |
1da177e4 | 805 | } |
d84f4f99 | 806 | |
1da177e4 | 807 | if (rgid != (gid_t) -1) |
d84f4f99 DH |
808 | new->gid = rgid; |
809 | if (egid != (gid_t) -1) | |
810 | new->egid = egid; | |
1da177e4 | 811 | if (sgid != (gid_t) -1) |
d84f4f99 DH |
812 | new->sgid = sgid; |
813 | new->fsgid = new->egid; | |
1da177e4 | 814 | |
d84f4f99 DH |
815 | return commit_creds(new); |
816 | ||
817 | error: | |
818 | abort_creds(new); | |
819 | return retval; | |
1da177e4 LT |
820 | } |
821 | ||
dbf040d9 | 822 | SYSCALL_DEFINE3(getresgid, gid_t __user *, rgid, gid_t __user *, egid, gid_t __user *, sgid) |
1da177e4 | 823 | { |
86a264ab | 824 | const struct cred *cred = current_cred(); |
1da177e4 LT |
825 | int retval; |
826 | ||
86a264ab DH |
827 | if (!(retval = put_user(cred->gid, rgid)) && |
828 | !(retval = put_user(cred->egid, egid))) | |
b6dff3ec | 829 | retval = put_user(cred->sgid, sgid); |
1da177e4 LT |
830 | |
831 | return retval; | |
832 | } | |
833 | ||
834 | ||
835 | /* | |
836 | * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This | |
837 | * is used for "access()" and for the NFS daemon (letting nfsd stay at | |
838 | * whatever uid it wants to). It normally shadows "euid", except when | |
839 | * explicitly set by setfsuid() or for access.. | |
840 | */ | |
ae1251ab | 841 | SYSCALL_DEFINE1(setfsuid, uid_t, uid) |
1da177e4 | 842 | { |
d84f4f99 DH |
843 | const struct cred *old; |
844 | struct cred *new; | |
845 | uid_t old_fsuid; | |
846 | ||
847 | new = prepare_creds(); | |
848 | if (!new) | |
849 | return current_fsuid(); | |
850 | old = current_cred(); | |
851 | old_fsuid = old->fsuid; | |
1da177e4 | 852 | |
d84f4f99 DH |
853 | if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS) < 0) |
854 | goto error; | |
1da177e4 | 855 | |
d84f4f99 DH |
856 | if (uid == old->uid || uid == old->euid || |
857 | uid == old->suid || uid == old->fsuid || | |
756184b7 CP |
858 | capable(CAP_SETUID)) { |
859 | if (uid != old_fsuid) { | |
d84f4f99 DH |
860 | new->fsuid = uid; |
861 | if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) | |
862 | goto change_okay; | |
1da177e4 | 863 | } |
1da177e4 LT |
864 | } |
865 | ||
d84f4f99 DH |
866 | error: |
867 | abort_creds(new); | |
868 | return old_fsuid; | |
1da177e4 | 869 | |
d84f4f99 DH |
870 | change_okay: |
871 | commit_creds(new); | |
1da177e4 LT |
872 | return old_fsuid; |
873 | } | |
874 | ||
875 | /* | |
f42df9e6 | 876 | * Samma på svenska.. |
1da177e4 | 877 | */ |
ae1251ab | 878 | SYSCALL_DEFINE1(setfsgid, gid_t, gid) |
1da177e4 | 879 | { |
d84f4f99 DH |
880 | const struct cred *old; |
881 | struct cred *new; | |
882 | gid_t old_fsgid; | |
883 | ||
884 | new = prepare_creds(); | |
885 | if (!new) | |
886 | return current_fsgid(); | |
887 | old = current_cred(); | |
888 | old_fsgid = old->fsgid; | |
1da177e4 | 889 | |
1da177e4 | 890 | if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS)) |
d84f4f99 | 891 | goto error; |
1da177e4 | 892 | |
d84f4f99 DH |
893 | if (gid == old->gid || gid == old->egid || |
894 | gid == old->sgid || gid == old->fsgid || | |
756184b7 CP |
895 | capable(CAP_SETGID)) { |
896 | if (gid != old_fsgid) { | |
d84f4f99 DH |
897 | new->fsgid = gid; |
898 | goto change_okay; | |
1da177e4 | 899 | } |
1da177e4 | 900 | } |
d84f4f99 DH |
901 | |
902 | error: | |
903 | abort_creds(new); | |
904 | return old_fsgid; | |
905 | ||
906 | change_okay: | |
907 | commit_creds(new); | |
1da177e4 LT |
908 | return old_fsgid; |
909 | } | |
910 | ||
f06febc9 FM |
911 | void do_sys_times(struct tms *tms) |
912 | { | |
913 | struct task_cputime cputime; | |
914 | cputime_t cutime, cstime; | |
915 | ||
f06febc9 | 916 | thread_group_cputime(current, &cputime); |
2b5fe6de | 917 | spin_lock_irq(¤t->sighand->siglock); |
f06febc9 FM |
918 | cutime = current->signal->cutime; |
919 | cstime = current->signal->cstime; | |
920 | spin_unlock_irq(¤t->sighand->siglock); | |
921 | tms->tms_utime = cputime_to_clock_t(cputime.utime); | |
922 | tms->tms_stime = cputime_to_clock_t(cputime.stime); | |
923 | tms->tms_cutime = cputime_to_clock_t(cutime); | |
924 | tms->tms_cstime = cputime_to_clock_t(cstime); | |
925 | } | |
926 | ||
58fd3aa2 | 927 | SYSCALL_DEFINE1(times, struct tms __user *, tbuf) |
1da177e4 | 928 | { |
1da177e4 LT |
929 | if (tbuf) { |
930 | struct tms tmp; | |
f06febc9 FM |
931 | |
932 | do_sys_times(&tmp); | |
1da177e4 LT |
933 | if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
934 | return -EFAULT; | |
935 | } | |
e3d5a27d | 936 | force_successful_syscall_return(); |
1da177e4 LT |
937 | return (long) jiffies_64_to_clock_t(get_jiffies_64()); |
938 | } | |
939 | ||
940 | /* | |
941 | * This needs some heavy checking ... | |
942 | * I just haven't the stomach for it. I also don't fully | |
943 | * understand sessions/pgrp etc. Let somebody who does explain it. | |
944 | * | |
945 | * OK, I think I have the protection semantics right.... this is really | |
946 | * only important on a multi-user system anyway, to make sure one user | |
947 | * can't send a signal to a process owned by another. -TYT, 12/12/91 | |
948 | * | |
949 | * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. | |
950 | * LBT 04.03.94 | |
951 | */ | |
b290ebe2 | 952 | SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) |
1da177e4 LT |
953 | { |
954 | struct task_struct *p; | |
ee0acf90 | 955 | struct task_struct *group_leader = current->group_leader; |
4e021306 ON |
956 | struct pid *pgrp; |
957 | int err; | |
1da177e4 LT |
958 | |
959 | if (!pid) | |
b488893a | 960 | pid = task_pid_vnr(group_leader); |
1da177e4 LT |
961 | if (!pgid) |
962 | pgid = pid; | |
963 | if (pgid < 0) | |
964 | return -EINVAL; | |
965 | ||
966 | /* From this point forward we keep holding onto the tasklist lock | |
967 | * so that our parent does not change from under us. -DaveM | |
968 | */ | |
969 | write_lock_irq(&tasklist_lock); | |
970 | ||
971 | err = -ESRCH; | |
4e021306 | 972 | p = find_task_by_vpid(pid); |
1da177e4 LT |
973 | if (!p) |
974 | goto out; | |
975 | ||
976 | err = -EINVAL; | |
977 | if (!thread_group_leader(p)) | |
978 | goto out; | |
979 | ||
4e021306 | 980 | if (same_thread_group(p->real_parent, group_leader)) { |
1da177e4 | 981 | err = -EPERM; |
41487c65 | 982 | if (task_session(p) != task_session(group_leader)) |
1da177e4 LT |
983 | goto out; |
984 | err = -EACCES; | |
985 | if (p->did_exec) | |
986 | goto out; | |
987 | } else { | |
988 | err = -ESRCH; | |
ee0acf90 | 989 | if (p != group_leader) |
1da177e4 LT |
990 | goto out; |
991 | } | |
992 | ||
993 | err = -EPERM; | |
994 | if (p->signal->leader) | |
995 | goto out; | |
996 | ||
4e021306 | 997 | pgrp = task_pid(p); |
1da177e4 | 998 | if (pgid != pid) { |
b488893a | 999 | struct task_struct *g; |
1da177e4 | 1000 | |
4e021306 ON |
1001 | pgrp = find_vpid(pgid); |
1002 | g = pid_task(pgrp, PIDTYPE_PGID); | |
41487c65 | 1003 | if (!g || task_session(g) != task_session(group_leader)) |
f020bc46 | 1004 | goto out; |
1da177e4 LT |
1005 | } |
1006 | ||
1da177e4 LT |
1007 | err = security_task_setpgid(p, pgid); |
1008 | if (err) | |
1009 | goto out; | |
1010 | ||
1b0f7ffd | 1011 | if (task_pgrp(p) != pgrp) |
83beaf3c | 1012 | change_pid(p, PIDTYPE_PGID, pgrp); |
1da177e4 LT |
1013 | |
1014 | err = 0; | |
1015 | out: | |
1016 | /* All paths lead to here, thus we are safe. -DaveM */ | |
1017 | write_unlock_irq(&tasklist_lock); | |
1018 | return err; | |
1019 | } | |
1020 | ||
dbf040d9 | 1021 | SYSCALL_DEFINE1(getpgid, pid_t, pid) |
1da177e4 | 1022 | { |
12a3de0a ON |
1023 | struct task_struct *p; |
1024 | struct pid *grp; | |
1025 | int retval; | |
1026 | ||
1027 | rcu_read_lock(); | |
756184b7 | 1028 | if (!pid) |
12a3de0a | 1029 | grp = task_pgrp(current); |
756184b7 | 1030 | else { |
1da177e4 | 1031 | retval = -ESRCH; |
12a3de0a ON |
1032 | p = find_task_by_vpid(pid); |
1033 | if (!p) | |
1034 | goto out; | |
1035 | grp = task_pgrp(p); | |
1036 | if (!grp) | |
1037 | goto out; | |
1038 | ||
1039 | retval = security_task_getpgid(p); | |
1040 | if (retval) | |
1041 | goto out; | |
1da177e4 | 1042 | } |
12a3de0a ON |
1043 | retval = pid_vnr(grp); |
1044 | out: | |
1045 | rcu_read_unlock(); | |
1046 | return retval; | |
1da177e4 LT |
1047 | } |
1048 | ||
1049 | #ifdef __ARCH_WANT_SYS_GETPGRP | |
1050 | ||
dbf040d9 | 1051 | SYSCALL_DEFINE0(getpgrp) |
1da177e4 | 1052 | { |
12a3de0a | 1053 | return sys_getpgid(0); |
1da177e4 LT |
1054 | } |
1055 | ||
1056 | #endif | |
1057 | ||
dbf040d9 | 1058 | SYSCALL_DEFINE1(getsid, pid_t, pid) |
1da177e4 | 1059 | { |
1dd768c0 ON |
1060 | struct task_struct *p; |
1061 | struct pid *sid; | |
1062 | int retval; | |
1063 | ||
1064 | rcu_read_lock(); | |
756184b7 | 1065 | if (!pid) |
1dd768c0 | 1066 | sid = task_session(current); |
756184b7 | 1067 | else { |
1da177e4 | 1068 | retval = -ESRCH; |
1dd768c0 ON |
1069 | p = find_task_by_vpid(pid); |
1070 | if (!p) | |
1071 | goto out; | |
1072 | sid = task_session(p); | |
1073 | if (!sid) | |
1074 | goto out; | |
1075 | ||
1076 | retval = security_task_getsid(p); | |
1077 | if (retval) | |
1078 | goto out; | |
1da177e4 | 1079 | } |
1dd768c0 ON |
1080 | retval = pid_vnr(sid); |
1081 | out: | |
1082 | rcu_read_unlock(); | |
1083 | return retval; | |
1da177e4 LT |
1084 | } |
1085 | ||
b290ebe2 | 1086 | SYSCALL_DEFINE0(setsid) |
1da177e4 | 1087 | { |
e19f247a | 1088 | struct task_struct *group_leader = current->group_leader; |
e4cc0a9c ON |
1089 | struct pid *sid = task_pid(group_leader); |
1090 | pid_t session = pid_vnr(sid); | |
1da177e4 LT |
1091 | int err = -EPERM; |
1092 | ||
1da177e4 | 1093 | write_lock_irq(&tasklist_lock); |
390e2ff0 EB |
1094 | /* Fail if I am already a session leader */ |
1095 | if (group_leader->signal->leader) | |
1096 | goto out; | |
1097 | ||
430c6231 ON |
1098 | /* Fail if a process group id already exists that equals the |
1099 | * proposed session id. | |
390e2ff0 | 1100 | */ |
6806aac6 | 1101 | if (pid_task(sid, PIDTYPE_PGID)) |
1da177e4 LT |
1102 | goto out; |
1103 | ||
e19f247a | 1104 | group_leader->signal->leader = 1; |
8520d7c7 | 1105 | __set_special_pids(sid); |
24ec839c | 1106 | |
9c9f4ded | 1107 | proc_clear_tty(group_leader); |
24ec839c | 1108 | |
e4cc0a9c | 1109 | err = session; |
1da177e4 LT |
1110 | out: |
1111 | write_unlock_irq(&tasklist_lock); | |
1da177e4 LT |
1112 | return err; |
1113 | } | |
1114 | ||
1115 | /* | |
1116 | * Supplementary group IDs | |
1117 | */ | |
1118 | ||
1119 | /* init to 2 - one for init_task, one to ensure it is never freed */ | |
1120 | struct group_info init_groups = { .usage = ATOMIC_INIT(2) }; | |
1121 | ||
1122 | struct group_info *groups_alloc(int gidsetsize) | |
1123 | { | |
1124 | struct group_info *group_info; | |
1125 | int nblocks; | |
1126 | int i; | |
1127 | ||
1128 | nblocks = (gidsetsize + NGROUPS_PER_BLOCK - 1) / NGROUPS_PER_BLOCK; | |
1129 | /* Make sure we always allocate at least one indirect block pointer */ | |
1130 | nblocks = nblocks ? : 1; | |
1131 | group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *), GFP_USER); | |
1132 | if (!group_info) | |
1133 | return NULL; | |
1134 | group_info->ngroups = gidsetsize; | |
1135 | group_info->nblocks = nblocks; | |
1136 | atomic_set(&group_info->usage, 1); | |
1137 | ||
756184b7 | 1138 | if (gidsetsize <= NGROUPS_SMALL) |
1da177e4 | 1139 | group_info->blocks[0] = group_info->small_block; |
756184b7 | 1140 | else { |
1da177e4 LT |
1141 | for (i = 0; i < nblocks; i++) { |
1142 | gid_t *b; | |
1143 | b = (void *)__get_free_page(GFP_USER); | |
1144 | if (!b) | |
1145 | goto out_undo_partial_alloc; | |
1146 | group_info->blocks[i] = b; | |
1147 | } | |
1148 | } | |
1149 | return group_info; | |
1150 | ||
1151 | out_undo_partial_alloc: | |
1152 | while (--i >= 0) { | |
1153 | free_page((unsigned long)group_info->blocks[i]); | |
1154 | } | |
1155 | kfree(group_info); | |
1156 | return NULL; | |
1157 | } | |
1158 | ||
1159 | EXPORT_SYMBOL(groups_alloc); | |
1160 | ||
1161 | void groups_free(struct group_info *group_info) | |
1162 | { | |
1163 | if (group_info->blocks[0] != group_info->small_block) { | |
1164 | int i; | |
1165 | for (i = 0; i < group_info->nblocks; i++) | |
1166 | free_page((unsigned long)group_info->blocks[i]); | |
1167 | } | |
1168 | kfree(group_info); | |
1169 | } | |
1170 | ||
1171 | EXPORT_SYMBOL(groups_free); | |
1172 | ||
1173 | /* export the group_info to a user-space array */ | |
1174 | static int groups_to_user(gid_t __user *grouplist, | |
d84f4f99 | 1175 | const struct group_info *group_info) |
1da177e4 LT |
1176 | { |
1177 | int i; | |
1bf47346 | 1178 | unsigned int count = group_info->ngroups; |
1da177e4 LT |
1179 | |
1180 | for (i = 0; i < group_info->nblocks; i++) { | |
1bf47346 ED |
1181 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
1182 | unsigned int len = cp_count * sizeof(*grouplist); | |
1da177e4 | 1183 | |
1bf47346 | 1184 | if (copy_to_user(grouplist, group_info->blocks[i], len)) |
1da177e4 LT |
1185 | return -EFAULT; |
1186 | ||
1bf47346 | 1187 | grouplist += NGROUPS_PER_BLOCK; |
1da177e4 LT |
1188 | count -= cp_count; |
1189 | } | |
1190 | return 0; | |
1191 | } | |
1192 | ||
1193 | /* fill a group_info from a user-space array - it must be allocated already */ | |
1194 | static int groups_from_user(struct group_info *group_info, | |
1195 | gid_t __user *grouplist) | |
756184b7 | 1196 | { |
1da177e4 | 1197 | int i; |
1bf47346 | 1198 | unsigned int count = group_info->ngroups; |
1da177e4 LT |
1199 | |
1200 | for (i = 0; i < group_info->nblocks; i++) { | |
1bf47346 ED |
1201 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
1202 | unsigned int len = cp_count * sizeof(*grouplist); | |
1da177e4 | 1203 | |
1bf47346 | 1204 | if (copy_from_user(group_info->blocks[i], grouplist, len)) |
1da177e4 LT |
1205 | return -EFAULT; |
1206 | ||
1bf47346 | 1207 | grouplist += NGROUPS_PER_BLOCK; |
1da177e4 LT |
1208 | count -= cp_count; |
1209 | } | |
1210 | return 0; | |
1211 | } | |
1212 | ||
ebe8b541 | 1213 | /* a simple Shell sort */ |
1da177e4 LT |
1214 | static void groups_sort(struct group_info *group_info) |
1215 | { | |
1216 | int base, max, stride; | |
1217 | int gidsetsize = group_info->ngroups; | |
1218 | ||
1219 | for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1) | |
1220 | ; /* nothing */ | |
1221 | stride /= 3; | |
1222 | ||
1223 | while (stride) { | |
1224 | max = gidsetsize - stride; | |
1225 | for (base = 0; base < max; base++) { | |
1226 | int left = base; | |
1227 | int right = left + stride; | |
1228 | gid_t tmp = GROUP_AT(group_info, right); | |
1229 | ||
1230 | while (left >= 0 && GROUP_AT(group_info, left) > tmp) { | |
1231 | GROUP_AT(group_info, right) = | |
1232 | GROUP_AT(group_info, left); | |
1233 | right = left; | |
1234 | left -= stride; | |
1235 | } | |
1236 | GROUP_AT(group_info, right) = tmp; | |
1237 | } | |
1238 | stride /= 3; | |
1239 | } | |
1240 | } | |
1241 | ||
1242 | /* a simple bsearch */ | |
86a264ab | 1243 | int groups_search(const struct group_info *group_info, gid_t grp) |
1da177e4 | 1244 | { |
d74beb9f | 1245 | unsigned int left, right; |
1da177e4 LT |
1246 | |
1247 | if (!group_info) | |
1248 | return 0; | |
1249 | ||
1250 | left = 0; | |
1251 | right = group_info->ngroups; | |
1252 | while (left < right) { | |
d74beb9f | 1253 | unsigned int mid = (left+right)/2; |
1da177e4 LT |
1254 | int cmp = grp - GROUP_AT(group_info, mid); |
1255 | if (cmp > 0) | |
1256 | left = mid + 1; | |
1257 | else if (cmp < 0) | |
1258 | right = mid; | |
1259 | else | |
1260 | return 1; | |
1261 | } | |
1262 | return 0; | |
1263 | } | |
1264 | ||
b6dff3ec | 1265 | /** |
d84f4f99 DH |
1266 | * set_groups - Change a group subscription in a set of credentials |
1267 | * @new: The newly prepared set of credentials to alter | |
1268 | * @group_info: The group list to install | |
b6dff3ec | 1269 | * |
d84f4f99 DH |
1270 | * Validate a group subscription and, if valid, insert it into a set |
1271 | * of credentials. | |
b6dff3ec | 1272 | */ |
d84f4f99 | 1273 | int set_groups(struct cred *new, struct group_info *group_info) |
1da177e4 LT |
1274 | { |
1275 | int retval; | |
1da177e4 LT |
1276 | |
1277 | retval = security_task_setgroups(group_info); | |
1278 | if (retval) | |
1279 | return retval; | |
1280 | ||
d84f4f99 | 1281 | put_group_info(new->group_info); |
1da177e4 LT |
1282 | groups_sort(group_info); |
1283 | get_group_info(group_info); | |
d84f4f99 | 1284 | new->group_info = group_info; |
1da177e4 LT |
1285 | return 0; |
1286 | } | |
1287 | ||
b6dff3ec DH |
1288 | EXPORT_SYMBOL(set_groups); |
1289 | ||
1290 | /** | |
1291 | * set_current_groups - Change current's group subscription | |
1292 | * @group_info: The group list to impose | |
1293 | * | |
1294 | * Validate a group subscription and, if valid, impose it upon current's task | |
1295 | * security record. | |
1296 | */ | |
1297 | int set_current_groups(struct group_info *group_info) | |
1298 | { | |
d84f4f99 DH |
1299 | struct cred *new; |
1300 | int ret; | |
1301 | ||
1302 | new = prepare_creds(); | |
1303 | if (!new) | |
1304 | return -ENOMEM; | |
1305 | ||
1306 | ret = set_groups(new, group_info); | |
1307 | if (ret < 0) { | |
1308 | abort_creds(new); | |
1309 | return ret; | |
1310 | } | |
1311 | ||
1312 | return commit_creds(new); | |
b6dff3ec DH |
1313 | } |
1314 | ||
1da177e4 LT |
1315 | EXPORT_SYMBOL(set_current_groups); |
1316 | ||
ae1251ab | 1317 | SYSCALL_DEFINE2(getgroups, int, gidsetsize, gid_t __user *, grouplist) |
1da177e4 | 1318 | { |
86a264ab DH |
1319 | const struct cred *cred = current_cred(); |
1320 | int i; | |
1da177e4 LT |
1321 | |
1322 | if (gidsetsize < 0) | |
1323 | return -EINVAL; | |
1324 | ||
1325 | /* no need to grab task_lock here; it cannot change */ | |
b6dff3ec | 1326 | i = cred->group_info->ngroups; |
1da177e4 LT |
1327 | if (gidsetsize) { |
1328 | if (i > gidsetsize) { | |
1329 | i = -EINVAL; | |
1330 | goto out; | |
1331 | } | |
b6dff3ec | 1332 | if (groups_to_user(grouplist, cred->group_info)) { |
1da177e4 LT |
1333 | i = -EFAULT; |
1334 | goto out; | |
1335 | } | |
1336 | } | |
1337 | out: | |
1da177e4 LT |
1338 | return i; |
1339 | } | |
1340 | ||
1341 | /* | |
1342 | * SMP: Our groups are copy-on-write. We can set them safely | |
1343 | * without another task interfering. | |
1344 | */ | |
1345 | ||
b290ebe2 | 1346 | SYSCALL_DEFINE2(setgroups, int, gidsetsize, gid_t __user *, grouplist) |
1da177e4 LT |
1347 | { |
1348 | struct group_info *group_info; | |
1349 | int retval; | |
1350 | ||
1351 | if (!capable(CAP_SETGID)) | |
1352 | return -EPERM; | |
1353 | if ((unsigned)gidsetsize > NGROUPS_MAX) | |
1354 | return -EINVAL; | |
1355 | ||
1356 | group_info = groups_alloc(gidsetsize); | |
1357 | if (!group_info) | |
1358 | return -ENOMEM; | |
1359 | retval = groups_from_user(group_info, grouplist); | |
1360 | if (retval) { | |
1361 | put_group_info(group_info); | |
1362 | return retval; | |
1363 | } | |
1364 | ||
1365 | retval = set_current_groups(group_info); | |
1366 | put_group_info(group_info); | |
1367 | ||
1368 | return retval; | |
1369 | } | |
1370 | ||
1371 | /* | |
1372 | * Check whether we're fsgid/egid or in the supplemental group.. | |
1373 | */ | |
1374 | int in_group_p(gid_t grp) | |
1375 | { | |
86a264ab | 1376 | const struct cred *cred = current_cred(); |
1da177e4 | 1377 | int retval = 1; |
86a264ab | 1378 | |
b6dff3ec DH |
1379 | if (grp != cred->fsgid) |
1380 | retval = groups_search(cred->group_info, grp); | |
1da177e4 LT |
1381 | return retval; |
1382 | } | |
1383 | ||
1384 | EXPORT_SYMBOL(in_group_p); | |
1385 | ||
1386 | int in_egroup_p(gid_t grp) | |
1387 | { | |
86a264ab | 1388 | const struct cred *cred = current_cred(); |
1da177e4 | 1389 | int retval = 1; |
86a264ab | 1390 | |
b6dff3ec DH |
1391 | if (grp != cred->egid) |
1392 | retval = groups_search(cred->group_info, grp); | |
1da177e4 LT |
1393 | return retval; |
1394 | } | |
1395 | ||
1396 | EXPORT_SYMBOL(in_egroup_p); | |
1397 | ||
1398 | DECLARE_RWSEM(uts_sem); | |
1399 | ||
e48fbb69 | 1400 | SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name) |
1da177e4 LT |
1401 | { |
1402 | int errno = 0; | |
1403 | ||
1404 | down_read(&uts_sem); | |
e9ff3990 | 1405 | if (copy_to_user(name, utsname(), sizeof *name)) |
1da177e4 LT |
1406 | errno = -EFAULT; |
1407 | up_read(&uts_sem); | |
1408 | return errno; | |
1409 | } | |
1410 | ||
5a8a82b1 | 1411 | SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) |
1da177e4 LT |
1412 | { |
1413 | int errno; | |
1414 | char tmp[__NEW_UTS_LEN]; | |
1415 | ||
1416 | if (!capable(CAP_SYS_ADMIN)) | |
1417 | return -EPERM; | |
1418 | if (len < 0 || len > __NEW_UTS_LEN) | |
1419 | return -EINVAL; | |
1420 | down_write(&uts_sem); | |
1421 | errno = -EFAULT; | |
1422 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1423 | struct new_utsname *u = utsname(); |
1424 | ||
1425 | memcpy(u->nodename, tmp, len); | |
1426 | memset(u->nodename + len, 0, sizeof(u->nodename) - len); | |
1da177e4 LT |
1427 | errno = 0; |
1428 | } | |
1429 | up_write(&uts_sem); | |
1430 | return errno; | |
1431 | } | |
1432 | ||
1433 | #ifdef __ARCH_WANT_SYS_GETHOSTNAME | |
1434 | ||
5a8a82b1 | 1435 | SYSCALL_DEFINE2(gethostname, char __user *, name, int, len) |
1da177e4 LT |
1436 | { |
1437 | int i, errno; | |
9679e4dd | 1438 | struct new_utsname *u; |
1da177e4 LT |
1439 | |
1440 | if (len < 0) | |
1441 | return -EINVAL; | |
1442 | down_read(&uts_sem); | |
9679e4dd AM |
1443 | u = utsname(); |
1444 | i = 1 + strlen(u->nodename); | |
1da177e4 LT |
1445 | if (i > len) |
1446 | i = len; | |
1447 | errno = 0; | |
9679e4dd | 1448 | if (copy_to_user(name, u->nodename, i)) |
1da177e4 LT |
1449 | errno = -EFAULT; |
1450 | up_read(&uts_sem); | |
1451 | return errno; | |
1452 | } | |
1453 | ||
1454 | #endif | |
1455 | ||
1456 | /* | |
1457 | * Only setdomainname; getdomainname can be implemented by calling | |
1458 | * uname() | |
1459 | */ | |
5a8a82b1 | 1460 | SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) |
1da177e4 LT |
1461 | { |
1462 | int errno; | |
1463 | char tmp[__NEW_UTS_LEN]; | |
1464 | ||
1465 | if (!capable(CAP_SYS_ADMIN)) | |
1466 | return -EPERM; | |
1467 | if (len < 0 || len > __NEW_UTS_LEN) | |
1468 | return -EINVAL; | |
1469 | ||
1470 | down_write(&uts_sem); | |
1471 | errno = -EFAULT; | |
1472 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1473 | struct new_utsname *u = utsname(); |
1474 | ||
1475 | memcpy(u->domainname, tmp, len); | |
1476 | memset(u->domainname + len, 0, sizeof(u->domainname) - len); | |
1da177e4 LT |
1477 | errno = 0; |
1478 | } | |
1479 | up_write(&uts_sem); | |
1480 | return errno; | |
1481 | } | |
1482 | ||
e48fbb69 | 1483 | SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1da177e4 LT |
1484 | { |
1485 | if (resource >= RLIM_NLIMITS) | |
1486 | return -EINVAL; | |
1487 | else { | |
1488 | struct rlimit value; | |
1489 | task_lock(current->group_leader); | |
1490 | value = current->signal->rlim[resource]; | |
1491 | task_unlock(current->group_leader); | |
1492 | return copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; | |
1493 | } | |
1494 | } | |
1495 | ||
1496 | #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT | |
1497 | ||
1498 | /* | |
1499 | * Back compatibility for getrlimit. Needed for some apps. | |
1500 | */ | |
1501 | ||
e48fbb69 HC |
1502 | SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, |
1503 | struct rlimit __user *, rlim) | |
1da177e4 LT |
1504 | { |
1505 | struct rlimit x; | |
1506 | if (resource >= RLIM_NLIMITS) | |
1507 | return -EINVAL; | |
1508 | ||
1509 | task_lock(current->group_leader); | |
1510 | x = current->signal->rlim[resource]; | |
1511 | task_unlock(current->group_leader); | |
756184b7 | 1512 | if (x.rlim_cur > 0x7FFFFFFF) |
1da177e4 | 1513 | x.rlim_cur = 0x7FFFFFFF; |
756184b7 | 1514 | if (x.rlim_max > 0x7FFFFFFF) |
1da177e4 LT |
1515 | x.rlim_max = 0x7FFFFFFF; |
1516 | return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0; | |
1517 | } | |
1518 | ||
1519 | #endif | |
1520 | ||
e48fbb69 | 1521 | SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1da177e4 LT |
1522 | { |
1523 | struct rlimit new_rlim, *old_rlim; | |
1524 | int retval; | |
1525 | ||
1526 | if (resource >= RLIM_NLIMITS) | |
1527 | return -EINVAL; | |
ec9e16ba | 1528 | if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) |
1da177e4 | 1529 | return -EFAULT; |
60fd760f AM |
1530 | if (new_rlim.rlim_cur > new_rlim.rlim_max) |
1531 | return -EINVAL; | |
1da177e4 LT |
1532 | old_rlim = current->signal->rlim + resource; |
1533 | if ((new_rlim.rlim_max > old_rlim->rlim_max) && | |
1534 | !capable(CAP_SYS_RESOURCE)) | |
1535 | return -EPERM; | |
60fd760f AM |
1536 | if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open) |
1537 | return -EPERM; | |
1da177e4 LT |
1538 | |
1539 | retval = security_task_setrlimit(resource, &new_rlim); | |
1540 | if (retval) | |
1541 | return retval; | |
1542 | ||
9926e4c7 TA |
1543 | if (resource == RLIMIT_CPU && new_rlim.rlim_cur == 0) { |
1544 | /* | |
1545 | * The caller is asking for an immediate RLIMIT_CPU | |
1546 | * expiry. But we use the zero value to mean "it was | |
1547 | * never set". So let's cheat and make it one second | |
1548 | * instead | |
1549 | */ | |
1550 | new_rlim.rlim_cur = 1; | |
1551 | } | |
1552 | ||
1da177e4 LT |
1553 | task_lock(current->group_leader); |
1554 | *old_rlim = new_rlim; | |
1555 | task_unlock(current->group_leader); | |
1556 | ||
ec9e16ba AM |
1557 | if (resource != RLIMIT_CPU) |
1558 | goto out; | |
d3561f78 AM |
1559 | |
1560 | /* | |
1561 | * RLIMIT_CPU handling. Note that the kernel fails to return an error | |
1562 | * code if it rejected the user's attempt to set RLIMIT_CPU. This is a | |
1563 | * very long-standing error, and fixing it now risks breakage of | |
1564 | * applications, so we live with it | |
1565 | */ | |
ec9e16ba AM |
1566 | if (new_rlim.rlim_cur == RLIM_INFINITY) |
1567 | goto out; | |
1568 | ||
f06febc9 | 1569 | update_rlimit_cpu(new_rlim.rlim_cur); |
ec9e16ba | 1570 | out: |
1da177e4 LT |
1571 | return 0; |
1572 | } | |
1573 | ||
1574 | /* | |
1575 | * It would make sense to put struct rusage in the task_struct, | |
1576 | * except that would make the task_struct be *really big*. After | |
1577 | * task_struct gets moved into malloc'ed memory, it would | |
1578 | * make sense to do this. It will make moving the rest of the information | |
1579 | * a lot simpler! (Which we're not doing right now because we're not | |
1580 | * measuring them yet). | |
1581 | * | |
1da177e4 LT |
1582 | * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
1583 | * races with threads incrementing their own counters. But since word | |
1584 | * reads are atomic, we either get new values or old values and we don't | |
1585 | * care which for the sums. We always take the siglock to protect reading | |
1586 | * the c* fields from p->signal from races with exit.c updating those | |
1587 | * fields when reaping, so a sample either gets all the additions of a | |
1588 | * given child after it's reaped, or none so this sample is before reaping. | |
2dd0ebcd | 1589 | * |
de047c1b RT |
1590 | * Locking: |
1591 | * We need to take the siglock for CHILDEREN, SELF and BOTH | |
1592 | * for the cases current multithreaded, non-current single threaded | |
1593 | * non-current multithreaded. Thread traversal is now safe with | |
1594 | * the siglock held. | |
1595 | * Strictly speaking, we donot need to take the siglock if we are current and | |
1596 | * single threaded, as no one else can take our signal_struct away, no one | |
1597 | * else can reap the children to update signal->c* counters, and no one else | |
1598 | * can race with the signal-> fields. If we do not take any lock, the | |
1599 | * signal-> fields could be read out of order while another thread was just | |
1600 | * exiting. So we should place a read memory barrier when we avoid the lock. | |
1601 | * On the writer side, write memory barrier is implied in __exit_signal | |
1602 | * as __exit_signal releases the siglock spinlock after updating the signal-> | |
1603 | * fields. But we don't do this yet to keep things simple. | |
2dd0ebcd | 1604 | * |
1da177e4 LT |
1605 | */ |
1606 | ||
f06febc9 | 1607 | static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) |
679c9cd4 | 1608 | { |
679c9cd4 SK |
1609 | r->ru_nvcsw += t->nvcsw; |
1610 | r->ru_nivcsw += t->nivcsw; | |
1611 | r->ru_minflt += t->min_flt; | |
1612 | r->ru_majflt += t->maj_flt; | |
1613 | r->ru_inblock += task_io_get_inblock(t); | |
1614 | r->ru_oublock += task_io_get_oublock(t); | |
1615 | } | |
1616 | ||
1da177e4 LT |
1617 | static void k_getrusage(struct task_struct *p, int who, struct rusage *r) |
1618 | { | |
1619 | struct task_struct *t; | |
1620 | unsigned long flags; | |
1621 | cputime_t utime, stime; | |
f06febc9 | 1622 | struct task_cputime cputime; |
1da177e4 LT |
1623 | |
1624 | memset((char *) r, 0, sizeof *r); | |
2dd0ebcd | 1625 | utime = stime = cputime_zero; |
1da177e4 | 1626 | |
679c9cd4 | 1627 | if (who == RUSAGE_THREAD) { |
8916edef KM |
1628 | utime = task_utime(current); |
1629 | stime = task_stime(current); | |
f06febc9 | 1630 | accumulate_thread_rusage(p, r); |
679c9cd4 SK |
1631 | goto out; |
1632 | } | |
1633 | ||
d6cf723a | 1634 | if (!lock_task_sighand(p, &flags)) |
de047c1b | 1635 | return; |
0f59cc4a | 1636 | |
1da177e4 | 1637 | switch (who) { |
0f59cc4a | 1638 | case RUSAGE_BOTH: |
1da177e4 | 1639 | case RUSAGE_CHILDREN: |
1da177e4 LT |
1640 | utime = p->signal->cutime; |
1641 | stime = p->signal->cstime; | |
1642 | r->ru_nvcsw = p->signal->cnvcsw; | |
1643 | r->ru_nivcsw = p->signal->cnivcsw; | |
1644 | r->ru_minflt = p->signal->cmin_flt; | |
1645 | r->ru_majflt = p->signal->cmaj_flt; | |
6eaeeaba ED |
1646 | r->ru_inblock = p->signal->cinblock; |
1647 | r->ru_oublock = p->signal->coublock; | |
0f59cc4a ON |
1648 | |
1649 | if (who == RUSAGE_CHILDREN) | |
1650 | break; | |
1651 | ||
1da177e4 | 1652 | case RUSAGE_SELF: |
f06febc9 FM |
1653 | thread_group_cputime(p, &cputime); |
1654 | utime = cputime_add(utime, cputime.utime); | |
1655 | stime = cputime_add(stime, cputime.stime); | |
1da177e4 LT |
1656 | r->ru_nvcsw += p->signal->nvcsw; |
1657 | r->ru_nivcsw += p->signal->nivcsw; | |
1658 | r->ru_minflt += p->signal->min_flt; | |
1659 | r->ru_majflt += p->signal->maj_flt; | |
6eaeeaba ED |
1660 | r->ru_inblock += p->signal->inblock; |
1661 | r->ru_oublock += p->signal->oublock; | |
1da177e4 LT |
1662 | t = p; |
1663 | do { | |
f06febc9 | 1664 | accumulate_thread_rusage(t, r); |
1da177e4 LT |
1665 | t = next_thread(t); |
1666 | } while (t != p); | |
1da177e4 | 1667 | break; |
0f59cc4a | 1668 | |
1da177e4 LT |
1669 | default: |
1670 | BUG(); | |
1671 | } | |
de047c1b | 1672 | unlock_task_sighand(p, &flags); |
de047c1b | 1673 | |
679c9cd4 | 1674 | out: |
0f59cc4a ON |
1675 | cputime_to_timeval(utime, &r->ru_utime); |
1676 | cputime_to_timeval(stime, &r->ru_stime); | |
1da177e4 LT |
1677 | } |
1678 | ||
1679 | int getrusage(struct task_struct *p, int who, struct rusage __user *ru) | |
1680 | { | |
1681 | struct rusage r; | |
1da177e4 | 1682 | k_getrusage(p, who, &r); |
1da177e4 LT |
1683 | return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
1684 | } | |
1685 | ||
e48fbb69 | 1686 | SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) |
1da177e4 | 1687 | { |
679c9cd4 SK |
1688 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
1689 | who != RUSAGE_THREAD) | |
1da177e4 LT |
1690 | return -EINVAL; |
1691 | return getrusage(current, who, ru); | |
1692 | } | |
1693 | ||
e48fbb69 | 1694 | SYSCALL_DEFINE1(umask, int, mask) |
1da177e4 LT |
1695 | { |
1696 | mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); | |
1697 | return mask; | |
1698 | } | |
3b7391de | 1699 | |
c4ea37c2 HC |
1700 | SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, |
1701 | unsigned long, arg4, unsigned long, arg5) | |
1da177e4 | 1702 | { |
b6dff3ec DH |
1703 | struct task_struct *me = current; |
1704 | unsigned char comm[sizeof(me->comm)]; | |
1705 | long error; | |
1da177e4 | 1706 | |
d84f4f99 DH |
1707 | error = security_task_prctl(option, arg2, arg3, arg4, arg5); |
1708 | if (error != -ENOSYS) | |
1da177e4 LT |
1709 | return error; |
1710 | ||
d84f4f99 | 1711 | error = 0; |
1da177e4 LT |
1712 | switch (option) { |
1713 | case PR_SET_PDEATHSIG: | |
0730ded5 | 1714 | if (!valid_signal(arg2)) { |
1da177e4 LT |
1715 | error = -EINVAL; |
1716 | break; | |
1717 | } | |
b6dff3ec DH |
1718 | me->pdeath_signal = arg2; |
1719 | error = 0; | |
1da177e4 LT |
1720 | break; |
1721 | case PR_GET_PDEATHSIG: | |
b6dff3ec | 1722 | error = put_user(me->pdeath_signal, (int __user *)arg2); |
1da177e4 LT |
1723 | break; |
1724 | case PR_GET_DUMPABLE: | |
b6dff3ec | 1725 | error = get_dumpable(me->mm); |
1da177e4 LT |
1726 | break; |
1727 | case PR_SET_DUMPABLE: | |
abf75a50 | 1728 | if (arg2 < 0 || arg2 > 1) { |
1da177e4 LT |
1729 | error = -EINVAL; |
1730 | break; | |
1731 | } | |
b6dff3ec DH |
1732 | set_dumpable(me->mm, arg2); |
1733 | error = 0; | |
1da177e4 LT |
1734 | break; |
1735 | ||
1736 | case PR_SET_UNALIGN: | |
b6dff3ec | 1737 | error = SET_UNALIGN_CTL(me, arg2); |
1da177e4 LT |
1738 | break; |
1739 | case PR_GET_UNALIGN: | |
b6dff3ec | 1740 | error = GET_UNALIGN_CTL(me, arg2); |
1da177e4 LT |
1741 | break; |
1742 | case PR_SET_FPEMU: | |
b6dff3ec | 1743 | error = SET_FPEMU_CTL(me, arg2); |
1da177e4 LT |
1744 | break; |
1745 | case PR_GET_FPEMU: | |
b6dff3ec | 1746 | error = GET_FPEMU_CTL(me, arg2); |
1da177e4 LT |
1747 | break; |
1748 | case PR_SET_FPEXC: | |
b6dff3ec | 1749 | error = SET_FPEXC_CTL(me, arg2); |
1da177e4 LT |
1750 | break; |
1751 | case PR_GET_FPEXC: | |
b6dff3ec | 1752 | error = GET_FPEXC_CTL(me, arg2); |
1da177e4 LT |
1753 | break; |
1754 | case PR_GET_TIMING: | |
1755 | error = PR_TIMING_STATISTICAL; | |
1756 | break; | |
1757 | case PR_SET_TIMING: | |
7b26655f | 1758 | if (arg2 != PR_TIMING_STATISTICAL) |
1da177e4 | 1759 | error = -EINVAL; |
b6dff3ec DH |
1760 | else |
1761 | error = 0; | |
1da177e4 LT |
1762 | break; |
1763 | ||
b6dff3ec DH |
1764 | case PR_SET_NAME: |
1765 | comm[sizeof(me->comm)-1] = 0; | |
1766 | if (strncpy_from_user(comm, (char __user *)arg2, | |
1767 | sizeof(me->comm) - 1) < 0) | |
1da177e4 | 1768 | return -EFAULT; |
b6dff3ec | 1769 | set_task_comm(me, comm); |
1da177e4 | 1770 | return 0; |
b6dff3ec DH |
1771 | case PR_GET_NAME: |
1772 | get_task_comm(comm, me); | |
1773 | if (copy_to_user((char __user *)arg2, comm, | |
1774 | sizeof(comm))) | |
1da177e4 LT |
1775 | return -EFAULT; |
1776 | return 0; | |
651d765d | 1777 | case PR_GET_ENDIAN: |
b6dff3ec | 1778 | error = GET_ENDIAN(me, arg2); |
651d765d AB |
1779 | break; |
1780 | case PR_SET_ENDIAN: | |
b6dff3ec | 1781 | error = SET_ENDIAN(me, arg2); |
651d765d AB |
1782 | break; |
1783 | ||
1d9d02fe AA |
1784 | case PR_GET_SECCOMP: |
1785 | error = prctl_get_seccomp(); | |
1786 | break; | |
1787 | case PR_SET_SECCOMP: | |
1788 | error = prctl_set_seccomp(arg2); | |
1789 | break; | |
8fb402bc EB |
1790 | case PR_GET_TSC: |
1791 | error = GET_TSC_CTL(arg2); | |
1792 | break; | |
1793 | case PR_SET_TSC: | |
1794 | error = SET_TSC_CTL(arg2); | |
1795 | break; | |
6976675d AV |
1796 | case PR_GET_TIMERSLACK: |
1797 | error = current->timer_slack_ns; | |
1798 | break; | |
1799 | case PR_SET_TIMERSLACK: | |
1800 | if (arg2 <= 0) | |
1801 | current->timer_slack_ns = | |
1802 | current->default_timer_slack_ns; | |
1803 | else | |
1804 | current->timer_slack_ns = arg2; | |
b6dff3ec | 1805 | error = 0; |
6976675d | 1806 | break; |
1da177e4 LT |
1807 | default: |
1808 | error = -EINVAL; | |
1809 | break; | |
1810 | } | |
1811 | return error; | |
1812 | } | |
3cfc348b | 1813 | |
836f92ad HC |
1814 | SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep, |
1815 | struct getcpu_cache __user *, unused) | |
3cfc348b AK |
1816 | { |
1817 | int err = 0; | |
1818 | int cpu = raw_smp_processor_id(); | |
1819 | if (cpup) | |
1820 | err |= put_user(cpu, cpup); | |
1821 | if (nodep) | |
1822 | err |= put_user(cpu_to_node(cpu), nodep); | |
3cfc348b AK |
1823 | return err ? -EFAULT : 0; |
1824 | } | |
10a0a8d4 JF |
1825 | |
1826 | char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff"; | |
1827 | ||
1828 | static void argv_cleanup(char **argv, char **envp) | |
1829 | { | |
1830 | argv_free(argv); | |
1831 | } | |
1832 | ||
1833 | /** | |
1834 | * orderly_poweroff - Trigger an orderly system poweroff | |
1835 | * @force: force poweroff if command execution fails | |
1836 | * | |
1837 | * This may be called from any context to trigger a system shutdown. | |
1838 | * If the orderly shutdown fails, it will force an immediate shutdown. | |
1839 | */ | |
1840 | int orderly_poweroff(bool force) | |
1841 | { | |
1842 | int argc; | |
1843 | char **argv = argv_split(GFP_ATOMIC, poweroff_cmd, &argc); | |
1844 | static char *envp[] = { | |
1845 | "HOME=/", | |
1846 | "PATH=/sbin:/bin:/usr/sbin:/usr/bin", | |
1847 | NULL | |
1848 | }; | |
1849 | int ret = -ENOMEM; | |
1850 | struct subprocess_info *info; | |
1851 | ||
1852 | if (argv == NULL) { | |
1853 | printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n", | |
1854 | __func__, poweroff_cmd); | |
1855 | goto out; | |
1856 | } | |
1857 | ||
ac331d15 | 1858 | info = call_usermodehelper_setup(argv[0], argv, envp, GFP_ATOMIC); |
10a0a8d4 JF |
1859 | if (info == NULL) { |
1860 | argv_free(argv); | |
1861 | goto out; | |
1862 | } | |
1863 | ||
1864 | call_usermodehelper_setcleanup(info, argv_cleanup); | |
1865 | ||
86313c48 | 1866 | ret = call_usermodehelper_exec(info, UMH_NO_WAIT); |
10a0a8d4 JF |
1867 | |
1868 | out: | |
1869 | if (ret && force) { | |
1870 | printk(KERN_WARNING "Failed to start orderly shutdown: " | |
1871 | "forcing the issue\n"); | |
1872 | ||
1873 | /* I guess this should try to kick off some daemon to | |
1874 | sync and poweroff asap. Or not even bother syncing | |
1875 | if we're doing an emergency shutdown? */ | |
1876 | emergency_sync(); | |
1877 | kernel_power_off(); | |
1878 | } | |
1879 | ||
1880 | return ret; | |
1881 | } | |
1882 | EXPORT_SYMBOL_GPL(orderly_poweroff); |