Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/kernel/sys.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | */ | |
6 | ||
9984de1a | 7 | #include <linux/export.h> |
1da177e4 LT |
8 | #include <linux/mm.h> |
9 | #include <linux/utsname.h> | |
10 | #include <linux/mman.h> | |
1da177e4 LT |
11 | #include <linux/reboot.h> |
12 | #include <linux/prctl.h> | |
1da177e4 LT |
13 | #include <linux/highuid.h> |
14 | #include <linux/fs.h> | |
74da1ff7 | 15 | #include <linux/kmod.h> |
cdd6c482 | 16 | #include <linux/perf_event.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> |
e28cbf22 | 36 | #include <linux/personality.h> |
e3d5a27d | 37 | #include <linux/ptrace.h> |
5ad4e53b | 38 | #include <linux/fs_struct.h> |
b32dfe37 CG |
39 | #include <linux/file.h> |
40 | #include <linux/mount.h> | |
5a0e3ad6 | 41 | #include <linux/gfp.h> |
40dc166c | 42 | #include <linux/syscore_ops.h> |
be27425d AK |
43 | #include <linux/version.h> |
44 | #include <linux/ctype.h> | |
1da177e4 LT |
45 | |
46 | #include <linux/compat.h> | |
47 | #include <linux/syscalls.h> | |
00d7c05a | 48 | #include <linux/kprobes.h> |
acce292c | 49 | #include <linux/user_namespace.h> |
7fe5e042 | 50 | #include <linux/binfmts.h> |
1da177e4 | 51 | |
04c6862c | 52 | #include <linux/kmsg_dump.h> |
be27425d AK |
53 | /* Move somewhere else to avoid recompiling? */ |
54 | #include <generated/utsrelease.h> | |
04c6862c | 55 | |
1da177e4 LT |
56 | #include <asm/uaccess.h> |
57 | #include <asm/io.h> | |
58 | #include <asm/unistd.h> | |
59 | ||
60 | #ifndef SET_UNALIGN_CTL | |
61 | # define SET_UNALIGN_CTL(a,b) (-EINVAL) | |
62 | #endif | |
63 | #ifndef GET_UNALIGN_CTL | |
64 | # define GET_UNALIGN_CTL(a,b) (-EINVAL) | |
65 | #endif | |
66 | #ifndef SET_FPEMU_CTL | |
67 | # define SET_FPEMU_CTL(a,b) (-EINVAL) | |
68 | #endif | |
69 | #ifndef GET_FPEMU_CTL | |
70 | # define GET_FPEMU_CTL(a,b) (-EINVAL) | |
71 | #endif | |
72 | #ifndef SET_FPEXC_CTL | |
73 | # define SET_FPEXC_CTL(a,b) (-EINVAL) | |
74 | #endif | |
75 | #ifndef GET_FPEXC_CTL | |
76 | # define GET_FPEXC_CTL(a,b) (-EINVAL) | |
77 | #endif | |
651d765d AB |
78 | #ifndef GET_ENDIAN |
79 | # define GET_ENDIAN(a,b) (-EINVAL) | |
80 | #endif | |
81 | #ifndef SET_ENDIAN | |
82 | # define SET_ENDIAN(a,b) (-EINVAL) | |
83 | #endif | |
8fb402bc EB |
84 | #ifndef GET_TSC_CTL |
85 | # define GET_TSC_CTL(a) (-EINVAL) | |
86 | #endif | |
87 | #ifndef SET_TSC_CTL | |
88 | # define SET_TSC_CTL(a) (-EINVAL) | |
89 | #endif | |
1da177e4 LT |
90 | |
91 | /* | |
92 | * this is where the system-wide overflow UID and GID are defined, for | |
93 | * architectures that now have 32-bit UID/GID but didn't in the past | |
94 | */ | |
95 | ||
96 | int overflowuid = DEFAULT_OVERFLOWUID; | |
97 | int overflowgid = DEFAULT_OVERFLOWGID; | |
98 | ||
1da177e4 LT |
99 | EXPORT_SYMBOL(overflowuid); |
100 | EXPORT_SYMBOL(overflowgid); | |
1da177e4 LT |
101 | |
102 | /* | |
103 | * the same as above, but for filesystems which can only store a 16-bit | |
104 | * UID and GID. as such, this is needed on all architectures | |
105 | */ | |
106 | ||
107 | int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; | |
108 | int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; | |
109 | ||
110 | EXPORT_SYMBOL(fs_overflowuid); | |
111 | EXPORT_SYMBOL(fs_overflowgid); | |
112 | ||
113 | /* | |
114 | * this indicates whether you can reboot with ctrl-alt-del: the default is yes | |
115 | */ | |
116 | ||
117 | int C_A_D = 1; | |
9ec52099 CLG |
118 | struct pid *cad_pid; |
119 | EXPORT_SYMBOL(cad_pid); | |
1da177e4 | 120 | |
bd804eba RW |
121 | /* |
122 | * If set, this is used for preparing the system to power off. | |
123 | */ | |
124 | ||
125 | void (*pm_power_off_prepare)(void); | |
bd804eba | 126 | |
fc832ad3 SH |
127 | /* |
128 | * Returns true if current's euid is same as p's uid or euid, | |
129 | * or has CAP_SYS_NICE to p's user_ns. | |
130 | * | |
131 | * Called with rcu_read_lock, creds are safe | |
132 | */ | |
133 | static bool set_one_prio_perm(struct task_struct *p) | |
134 | { | |
135 | const struct cred *cred = current_cred(), *pcred = __task_cred(p); | |
136 | ||
5af66203 EB |
137 | if (uid_eq(pcred->uid, cred->euid) || |
138 | uid_eq(pcred->euid, cred->euid)) | |
fc832ad3 | 139 | return true; |
c4a4d603 | 140 | if (ns_capable(pcred->user_ns, CAP_SYS_NICE)) |
fc832ad3 SH |
141 | return true; |
142 | return false; | |
143 | } | |
144 | ||
c69e8d9c DH |
145 | /* |
146 | * set the priority of a task | |
147 | * - the caller must hold the RCU read lock | |
148 | */ | |
1da177e4 LT |
149 | static int set_one_prio(struct task_struct *p, int niceval, int error) |
150 | { | |
151 | int no_nice; | |
152 | ||
fc832ad3 | 153 | if (!set_one_prio_perm(p)) { |
1da177e4 LT |
154 | error = -EPERM; |
155 | goto out; | |
156 | } | |
e43379f1 | 157 | if (niceval < task_nice(p) && !can_nice(p, niceval)) { |
1da177e4 LT |
158 | error = -EACCES; |
159 | goto out; | |
160 | } | |
161 | no_nice = security_task_setnice(p, niceval); | |
162 | if (no_nice) { | |
163 | error = no_nice; | |
164 | goto out; | |
165 | } | |
166 | if (error == -ESRCH) | |
167 | error = 0; | |
168 | set_user_nice(p, niceval); | |
169 | out: | |
170 | return error; | |
171 | } | |
172 | ||
754fe8d2 | 173 | SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval) |
1da177e4 LT |
174 | { |
175 | struct task_struct *g, *p; | |
176 | struct user_struct *user; | |
86a264ab | 177 | const struct cred *cred = current_cred(); |
1da177e4 | 178 | int error = -EINVAL; |
41487c65 | 179 | struct pid *pgrp; |
7b44ab97 | 180 | kuid_t uid; |
1da177e4 | 181 | |
3e88c553 | 182 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
183 | goto out; |
184 | ||
185 | /* normalize: avoid signed division (rounding problems) */ | |
186 | error = -ESRCH; | |
187 | if (niceval < -20) | |
188 | niceval = -20; | |
189 | if (niceval > 19) | |
190 | niceval = 19; | |
191 | ||
d4581a23 | 192 | rcu_read_lock(); |
1da177e4 LT |
193 | read_lock(&tasklist_lock); |
194 | switch (which) { | |
195 | case PRIO_PROCESS: | |
41487c65 | 196 | if (who) |
228ebcbe | 197 | p = find_task_by_vpid(who); |
41487c65 EB |
198 | else |
199 | p = current; | |
1da177e4 LT |
200 | if (p) |
201 | error = set_one_prio(p, niceval, error); | |
202 | break; | |
203 | case PRIO_PGRP: | |
41487c65 | 204 | if (who) |
b488893a | 205 | pgrp = find_vpid(who); |
41487c65 EB |
206 | else |
207 | pgrp = task_pgrp(current); | |
2d70b68d | 208 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 | 209 | error = set_one_prio(p, niceval, error); |
2d70b68d | 210 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
211 | break; |
212 | case PRIO_USER: | |
7b44ab97 | 213 | uid = make_kuid(cred->user_ns, who); |
74ba508f | 214 | user = cred->user; |
1da177e4 | 215 | if (!who) |
078de5f7 EB |
216 | uid = cred->uid; |
217 | else if (!uid_eq(uid, cred->uid) && | |
7b44ab97 | 218 | !(user = find_user(uid))) |
86a264ab | 219 | goto out_unlock; /* No processes for this user */ |
1da177e4 | 220 | |
dfc6a736 | 221 | do_each_thread(g, p) { |
078de5f7 | 222 | if (uid_eq(task_uid(p), uid)) |
1da177e4 | 223 | error = set_one_prio(p, niceval, error); |
dfc6a736 | 224 | } while_each_thread(g, p); |
078de5f7 | 225 | if (!uid_eq(uid, cred->uid)) |
1da177e4 LT |
226 | free_uid(user); /* For find_user() */ |
227 | break; | |
228 | } | |
229 | out_unlock: | |
230 | read_unlock(&tasklist_lock); | |
d4581a23 | 231 | rcu_read_unlock(); |
1da177e4 LT |
232 | out: |
233 | return error; | |
234 | } | |
235 | ||
236 | /* | |
237 | * Ugh. To avoid negative return values, "getpriority()" will | |
238 | * not return the normal nice-value, but a negated value that | |
239 | * has been offset by 20 (ie it returns 40..1 instead of -20..19) | |
240 | * to stay compatible. | |
241 | */ | |
754fe8d2 | 242 | SYSCALL_DEFINE2(getpriority, int, which, int, who) |
1da177e4 LT |
243 | { |
244 | struct task_struct *g, *p; | |
245 | struct user_struct *user; | |
86a264ab | 246 | const struct cred *cred = current_cred(); |
1da177e4 | 247 | long niceval, retval = -ESRCH; |
41487c65 | 248 | struct pid *pgrp; |
7b44ab97 | 249 | kuid_t uid; |
1da177e4 | 250 | |
3e88c553 | 251 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
252 | return -EINVAL; |
253 | ||
70118837 | 254 | rcu_read_lock(); |
1da177e4 LT |
255 | read_lock(&tasklist_lock); |
256 | switch (which) { | |
257 | case PRIO_PROCESS: | |
41487c65 | 258 | if (who) |
228ebcbe | 259 | p = find_task_by_vpid(who); |
41487c65 EB |
260 | else |
261 | p = current; | |
1da177e4 LT |
262 | if (p) { |
263 | niceval = 20 - task_nice(p); | |
264 | if (niceval > retval) | |
265 | retval = niceval; | |
266 | } | |
267 | break; | |
268 | case PRIO_PGRP: | |
41487c65 | 269 | if (who) |
b488893a | 270 | pgrp = find_vpid(who); |
41487c65 EB |
271 | else |
272 | pgrp = task_pgrp(current); | |
2d70b68d | 273 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 LT |
274 | niceval = 20 - task_nice(p); |
275 | if (niceval > retval) | |
276 | retval = niceval; | |
2d70b68d | 277 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
278 | break; |
279 | case PRIO_USER: | |
7b44ab97 | 280 | uid = make_kuid(cred->user_ns, who); |
74ba508f | 281 | user = cred->user; |
1da177e4 | 282 | if (!who) |
078de5f7 EB |
283 | uid = cred->uid; |
284 | else if (!uid_eq(uid, cred->uid) && | |
7b44ab97 | 285 | !(user = find_user(uid))) |
86a264ab | 286 | goto out_unlock; /* No processes for this user */ |
1da177e4 | 287 | |
dfc6a736 | 288 | do_each_thread(g, p) { |
078de5f7 | 289 | if (uid_eq(task_uid(p), uid)) { |
1da177e4 LT |
290 | niceval = 20 - task_nice(p); |
291 | if (niceval > retval) | |
292 | retval = niceval; | |
293 | } | |
dfc6a736 | 294 | } while_each_thread(g, p); |
078de5f7 | 295 | if (!uid_eq(uid, cred->uid)) |
1da177e4 LT |
296 | free_uid(user); /* for find_user() */ |
297 | break; | |
298 | } | |
299 | out_unlock: | |
300 | read_unlock(&tasklist_lock); | |
70118837 | 301 | rcu_read_unlock(); |
1da177e4 LT |
302 | |
303 | return retval; | |
304 | } | |
305 | ||
e4c94330 EB |
306 | /** |
307 | * emergency_restart - reboot the system | |
308 | * | |
309 | * Without shutting down any hardware or taking any locks | |
310 | * reboot the system. This is called when we know we are in | |
311 | * trouble so this is our best effort to reboot. This is | |
312 | * safe to call in interrupt context. | |
313 | */ | |
7c903473 EB |
314 | void emergency_restart(void) |
315 | { | |
04c6862c | 316 | kmsg_dump(KMSG_DUMP_EMERG); |
7c903473 EB |
317 | machine_emergency_restart(); |
318 | } | |
319 | EXPORT_SYMBOL_GPL(emergency_restart); | |
320 | ||
ca195b7f | 321 | void kernel_restart_prepare(char *cmd) |
4a00ea1e | 322 | { |
e041c683 | 323 | blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd); |
4a00ea1e | 324 | system_state = SYSTEM_RESTART; |
b50fa7c8 | 325 | usermodehelper_disable(); |
4a00ea1e | 326 | device_shutdown(); |
40dc166c | 327 | syscore_shutdown(); |
e4c94330 | 328 | } |
1e5d5331 | 329 | |
c5f41752 AW |
330 | /** |
331 | * register_reboot_notifier - Register function to be called at reboot time | |
332 | * @nb: Info about notifier function to be called | |
333 | * | |
334 | * Registers a function with the list of functions | |
335 | * to be called at reboot time. | |
336 | * | |
337 | * Currently always returns zero, as blocking_notifier_chain_register() | |
338 | * always returns zero. | |
339 | */ | |
340 | int register_reboot_notifier(struct notifier_block *nb) | |
341 | { | |
342 | return blocking_notifier_chain_register(&reboot_notifier_list, nb); | |
343 | } | |
344 | EXPORT_SYMBOL(register_reboot_notifier); | |
345 | ||
346 | /** | |
347 | * unregister_reboot_notifier - Unregister previously registered reboot notifier | |
348 | * @nb: Hook to be unregistered | |
349 | * | |
350 | * Unregisters a previously registered reboot | |
351 | * notifier function. | |
352 | * | |
353 | * Returns zero on success, or %-ENOENT on failure. | |
354 | */ | |
355 | int unregister_reboot_notifier(struct notifier_block *nb) | |
356 | { | |
357 | return blocking_notifier_chain_unregister(&reboot_notifier_list, nb); | |
358 | } | |
359 | EXPORT_SYMBOL(unregister_reboot_notifier); | |
360 | ||
1e5d5331 RD |
361 | /** |
362 | * kernel_restart - reboot the system | |
363 | * @cmd: pointer to buffer containing command to execute for restart | |
b8887e6e | 364 | * or %NULL |
1e5d5331 RD |
365 | * |
366 | * Shutdown everything and perform a clean reboot. | |
367 | * This is not safe to call in interrupt context. | |
368 | */ | |
e4c94330 EB |
369 | void kernel_restart(char *cmd) |
370 | { | |
371 | kernel_restart_prepare(cmd); | |
f96972f2 | 372 | disable_nonboot_cpus(); |
756184b7 | 373 | if (!cmd) |
4a00ea1e | 374 | printk(KERN_EMERG "Restarting system.\n"); |
756184b7 | 375 | else |
4a00ea1e | 376 | printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd); |
04c6862c | 377 | kmsg_dump(KMSG_DUMP_RESTART); |
4a00ea1e EB |
378 | machine_restart(cmd); |
379 | } | |
380 | EXPORT_SYMBOL_GPL(kernel_restart); | |
381 | ||
4ef7229f | 382 | static void kernel_shutdown_prepare(enum system_states state) |
729b4d4c | 383 | { |
e041c683 | 384 | blocking_notifier_call_chain(&reboot_notifier_list, |
729b4d4c AS |
385 | (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL); |
386 | system_state = state; | |
b50fa7c8 | 387 | usermodehelper_disable(); |
729b4d4c AS |
388 | device_shutdown(); |
389 | } | |
e4c94330 EB |
390 | /** |
391 | * kernel_halt - halt the system | |
392 | * | |
393 | * Shutdown everything and perform a clean system halt. | |
394 | */ | |
e4c94330 EB |
395 | void kernel_halt(void) |
396 | { | |
729b4d4c | 397 | kernel_shutdown_prepare(SYSTEM_HALT); |
40dc166c | 398 | syscore_shutdown(); |
4a00ea1e | 399 | printk(KERN_EMERG "System halted.\n"); |
04c6862c | 400 | kmsg_dump(KMSG_DUMP_HALT); |
4a00ea1e EB |
401 | machine_halt(); |
402 | } | |
729b4d4c | 403 | |
4a00ea1e EB |
404 | EXPORT_SYMBOL_GPL(kernel_halt); |
405 | ||
e4c94330 EB |
406 | /** |
407 | * kernel_power_off - power_off the system | |
408 | * | |
409 | * Shutdown everything and perform a clean system power_off. | |
410 | */ | |
e4c94330 EB |
411 | void kernel_power_off(void) |
412 | { | |
729b4d4c | 413 | kernel_shutdown_prepare(SYSTEM_POWER_OFF); |
bd804eba RW |
414 | if (pm_power_off_prepare) |
415 | pm_power_off_prepare(); | |
4047727e | 416 | disable_nonboot_cpus(); |
40dc166c | 417 | syscore_shutdown(); |
4a00ea1e | 418 | printk(KERN_EMERG "Power down.\n"); |
04c6862c | 419 | kmsg_dump(KMSG_DUMP_POWEROFF); |
4a00ea1e EB |
420 | machine_power_off(); |
421 | } | |
422 | EXPORT_SYMBOL_GPL(kernel_power_off); | |
6f15fa50 TG |
423 | |
424 | static DEFINE_MUTEX(reboot_mutex); | |
425 | ||
1da177e4 LT |
426 | /* |
427 | * Reboot system call: for obvious reasons only root may call it, | |
428 | * and even root needs to set up some magic numbers in the registers | |
429 | * so that some mistake won't make this reboot the whole machine. | |
430 | * You can also set the meaning of the ctrl-alt-del-key here. | |
431 | * | |
432 | * reboot doesn't sync: do that yourself before calling this. | |
433 | */ | |
754fe8d2 HC |
434 | SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, |
435 | void __user *, arg) | |
1da177e4 LT |
436 | { |
437 | char buffer[256]; | |
3d26dcf7 | 438 | int ret = 0; |
1da177e4 LT |
439 | |
440 | /* We only trust the superuser with rebooting the system. */ | |
441 | if (!capable(CAP_SYS_BOOT)) | |
442 | return -EPERM; | |
443 | ||
444 | /* For safety, we require "magic" arguments. */ | |
445 | if (magic1 != LINUX_REBOOT_MAGIC1 || | |
446 | (magic2 != LINUX_REBOOT_MAGIC2 && | |
447 | magic2 != LINUX_REBOOT_MAGIC2A && | |
448 | magic2 != LINUX_REBOOT_MAGIC2B && | |
449 | magic2 != LINUX_REBOOT_MAGIC2C)) | |
450 | return -EINVAL; | |
451 | ||
cf3f8921 DL |
452 | /* |
453 | * If pid namespaces are enabled and the current task is in a child | |
454 | * pid_namespace, the command is handled by reboot_pid_ns() which will | |
455 | * call do_exit(). | |
456 | */ | |
457 | ret = reboot_pid_ns(task_active_pid_ns(current), cmd); | |
458 | if (ret) | |
459 | return ret; | |
460 | ||
5e38291d EB |
461 | /* Instead of trying to make the power_off code look like |
462 | * halt when pm_power_off is not set do it the easy way. | |
463 | */ | |
464 | if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off) | |
465 | cmd = LINUX_REBOOT_CMD_HALT; | |
466 | ||
6f15fa50 | 467 | mutex_lock(&reboot_mutex); |
1da177e4 LT |
468 | switch (cmd) { |
469 | case LINUX_REBOOT_CMD_RESTART: | |
4a00ea1e | 470 | kernel_restart(NULL); |
1da177e4 LT |
471 | break; |
472 | ||
473 | case LINUX_REBOOT_CMD_CAD_ON: | |
474 | C_A_D = 1; | |
475 | break; | |
476 | ||
477 | case LINUX_REBOOT_CMD_CAD_OFF: | |
478 | C_A_D = 0; | |
479 | break; | |
480 | ||
481 | case LINUX_REBOOT_CMD_HALT: | |
4a00ea1e | 482 | kernel_halt(); |
1da177e4 | 483 | do_exit(0); |
3d26dcf7 | 484 | panic("cannot halt"); |
1da177e4 LT |
485 | |
486 | case LINUX_REBOOT_CMD_POWER_OFF: | |
4a00ea1e | 487 | kernel_power_off(); |
1da177e4 LT |
488 | do_exit(0); |
489 | break; | |
490 | ||
491 | case LINUX_REBOOT_CMD_RESTART2: | |
492 | if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) { | |
6f15fa50 TG |
493 | ret = -EFAULT; |
494 | break; | |
1da177e4 LT |
495 | } |
496 | buffer[sizeof(buffer) - 1] = '\0'; | |
497 | ||
4a00ea1e | 498 | kernel_restart(buffer); |
1da177e4 LT |
499 | break; |
500 | ||
3ab83521 | 501 | #ifdef CONFIG_KEXEC |
dc009d92 | 502 | case LINUX_REBOOT_CMD_KEXEC: |
3d26dcf7 AK |
503 | ret = kernel_kexec(); |
504 | break; | |
3ab83521 | 505 | #endif |
4a00ea1e | 506 | |
b0cb1a19 | 507 | #ifdef CONFIG_HIBERNATION |
1da177e4 | 508 | case LINUX_REBOOT_CMD_SW_SUSPEND: |
3d26dcf7 AK |
509 | ret = hibernate(); |
510 | break; | |
1da177e4 LT |
511 | #endif |
512 | ||
513 | default: | |
3d26dcf7 AK |
514 | ret = -EINVAL; |
515 | break; | |
1da177e4 | 516 | } |
6f15fa50 | 517 | mutex_unlock(&reboot_mutex); |
3d26dcf7 | 518 | return ret; |
1da177e4 LT |
519 | } |
520 | ||
65f27f38 | 521 | static void deferred_cad(struct work_struct *dummy) |
1da177e4 | 522 | { |
abcd9e51 | 523 | kernel_restart(NULL); |
1da177e4 LT |
524 | } |
525 | ||
526 | /* | |
527 | * This function gets called by ctrl-alt-del - ie the keyboard interrupt. | |
528 | * As it's called within an interrupt, it may NOT sync: the only choice | |
529 | * is whether to reboot at once, or just ignore the ctrl-alt-del. | |
530 | */ | |
531 | void ctrl_alt_del(void) | |
532 | { | |
65f27f38 | 533 | static DECLARE_WORK(cad_work, deferred_cad); |
1da177e4 LT |
534 | |
535 | if (C_A_D) | |
536 | schedule_work(&cad_work); | |
537 | else | |
9ec52099 | 538 | kill_cad_pid(SIGINT, 1); |
1da177e4 LT |
539 | } |
540 | ||
1da177e4 LT |
541 | /* |
542 | * Unprivileged users may change the real gid to the effective gid | |
543 | * or vice versa. (BSD-style) | |
544 | * | |
545 | * If you set the real gid at all, or set the effective gid to a value not | |
546 | * equal to the real gid, then the saved gid is set to the new effective gid. | |
547 | * | |
548 | * This makes it possible for a setgid program to completely drop its | |
549 | * privileges, which is often a useful assertion to make when you are doing | |
550 | * a security audit over a program. | |
551 | * | |
552 | * The general idea is that a program which uses just setregid() will be | |
553 | * 100% compatible with BSD. A program which uses just setgid() will be | |
554 | * 100% compatible with POSIX with saved IDs. | |
555 | * | |
556 | * SMP: There are not races, the GIDs are checked only by filesystem | |
557 | * operations (as far as semantic preservation is concerned). | |
558 | */ | |
ae1251ab | 559 | SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) |
1da177e4 | 560 | { |
a29c33f4 | 561 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
562 | const struct cred *old; |
563 | struct cred *new; | |
1da177e4 | 564 | int retval; |
a29c33f4 EB |
565 | kgid_t krgid, kegid; |
566 | ||
567 | krgid = make_kgid(ns, rgid); | |
568 | kegid = make_kgid(ns, egid); | |
569 | ||
570 | if ((rgid != (gid_t) -1) && !gid_valid(krgid)) | |
571 | return -EINVAL; | |
572 | if ((egid != (gid_t) -1) && !gid_valid(kegid)) | |
573 | return -EINVAL; | |
1da177e4 | 574 | |
d84f4f99 DH |
575 | new = prepare_creds(); |
576 | if (!new) | |
577 | return -ENOMEM; | |
578 | old = current_cred(); | |
579 | ||
d84f4f99 | 580 | retval = -EPERM; |
1da177e4 | 581 | if (rgid != (gid_t) -1) { |
a29c33f4 EB |
582 | if (gid_eq(old->gid, krgid) || |
583 | gid_eq(old->egid, krgid) || | |
fc832ad3 | 584 | nsown_capable(CAP_SETGID)) |
a29c33f4 | 585 | new->gid = krgid; |
1da177e4 | 586 | else |
d84f4f99 | 587 | goto error; |
1da177e4 LT |
588 | } |
589 | if (egid != (gid_t) -1) { | |
a29c33f4 EB |
590 | if (gid_eq(old->gid, kegid) || |
591 | gid_eq(old->egid, kegid) || | |
592 | gid_eq(old->sgid, kegid) || | |
fc832ad3 | 593 | nsown_capable(CAP_SETGID)) |
a29c33f4 | 594 | new->egid = kegid; |
756184b7 | 595 | else |
d84f4f99 | 596 | goto error; |
1da177e4 | 597 | } |
d84f4f99 | 598 | |
1da177e4 | 599 | if (rgid != (gid_t) -1 || |
a29c33f4 | 600 | (egid != (gid_t) -1 && !gid_eq(kegid, old->gid))) |
d84f4f99 DH |
601 | new->sgid = new->egid; |
602 | new->fsgid = new->egid; | |
603 | ||
604 | return commit_creds(new); | |
605 | ||
606 | error: | |
607 | abort_creds(new); | |
608 | return retval; | |
1da177e4 LT |
609 | } |
610 | ||
611 | /* | |
612 | * setgid() is implemented like SysV w/ SAVED_IDS | |
613 | * | |
614 | * SMP: Same implicit races as above. | |
615 | */ | |
ae1251ab | 616 | SYSCALL_DEFINE1(setgid, gid_t, gid) |
1da177e4 | 617 | { |
a29c33f4 | 618 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
619 | const struct cred *old; |
620 | struct cred *new; | |
1da177e4 | 621 | int retval; |
a29c33f4 EB |
622 | kgid_t kgid; |
623 | ||
624 | kgid = make_kgid(ns, gid); | |
625 | if (!gid_valid(kgid)) | |
626 | return -EINVAL; | |
1da177e4 | 627 | |
d84f4f99 DH |
628 | new = prepare_creds(); |
629 | if (!new) | |
630 | return -ENOMEM; | |
631 | old = current_cred(); | |
632 | ||
d84f4f99 | 633 | retval = -EPERM; |
fc832ad3 | 634 | if (nsown_capable(CAP_SETGID)) |
a29c33f4 EB |
635 | new->gid = new->egid = new->sgid = new->fsgid = kgid; |
636 | else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid)) | |
637 | new->egid = new->fsgid = kgid; | |
1da177e4 | 638 | else |
d84f4f99 | 639 | goto error; |
1da177e4 | 640 | |
d84f4f99 DH |
641 | return commit_creds(new); |
642 | ||
643 | error: | |
644 | abort_creds(new); | |
645 | return retval; | |
1da177e4 | 646 | } |
54e99124 | 647 | |
d84f4f99 DH |
648 | /* |
649 | * change the user struct in a credentials set to match the new UID | |
650 | */ | |
651 | static int set_user(struct cred *new) | |
1da177e4 LT |
652 | { |
653 | struct user_struct *new_user; | |
654 | ||
078de5f7 | 655 | new_user = alloc_uid(new->uid); |
1da177e4 LT |
656 | if (!new_user) |
657 | return -EAGAIN; | |
658 | ||
72fa5997 VK |
659 | /* |
660 | * We don't fail in case of NPROC limit excess here because too many | |
661 | * poorly written programs don't check set*uid() return code, assuming | |
662 | * it never fails if called by root. We may still enforce NPROC limit | |
663 | * for programs doing set*uid()+execve() by harmlessly deferring the | |
664 | * failure to the execve() stage. | |
665 | */ | |
78d7d407 | 666 | if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) && |
72fa5997 VK |
667 | new_user != INIT_USER) |
668 | current->flags |= PF_NPROC_EXCEEDED; | |
669 | else | |
670 | current->flags &= ~PF_NPROC_EXCEEDED; | |
1da177e4 | 671 | |
d84f4f99 DH |
672 | free_uid(new->user); |
673 | new->user = new_user; | |
1da177e4 LT |
674 | return 0; |
675 | } | |
676 | ||
677 | /* | |
678 | * Unprivileged users may change the real uid to the effective uid | |
679 | * or vice versa. (BSD-style) | |
680 | * | |
681 | * If you set the real uid at all, or set the effective uid to a value not | |
682 | * equal to the real uid, then the saved uid is set to the new effective uid. | |
683 | * | |
684 | * This makes it possible for a setuid program to completely drop its | |
685 | * privileges, which is often a useful assertion to make when you are doing | |
686 | * a security audit over a program. | |
687 | * | |
688 | * The general idea is that a program which uses just setreuid() will be | |
689 | * 100% compatible with BSD. A program which uses just setuid() will be | |
690 | * 100% compatible with POSIX with saved IDs. | |
691 | */ | |
ae1251ab | 692 | SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) |
1da177e4 | 693 | { |
a29c33f4 | 694 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
695 | const struct cred *old; |
696 | struct cred *new; | |
1da177e4 | 697 | int retval; |
a29c33f4 EB |
698 | kuid_t kruid, keuid; |
699 | ||
700 | kruid = make_kuid(ns, ruid); | |
701 | keuid = make_kuid(ns, euid); | |
702 | ||
703 | if ((ruid != (uid_t) -1) && !uid_valid(kruid)) | |
704 | return -EINVAL; | |
705 | if ((euid != (uid_t) -1) && !uid_valid(keuid)) | |
706 | return -EINVAL; | |
1da177e4 | 707 | |
d84f4f99 DH |
708 | new = prepare_creds(); |
709 | if (!new) | |
710 | return -ENOMEM; | |
711 | old = current_cred(); | |
712 | ||
d84f4f99 | 713 | retval = -EPERM; |
1da177e4 | 714 | if (ruid != (uid_t) -1) { |
a29c33f4 EB |
715 | new->uid = kruid; |
716 | if (!uid_eq(old->uid, kruid) && | |
717 | !uid_eq(old->euid, kruid) && | |
fc832ad3 | 718 | !nsown_capable(CAP_SETUID)) |
d84f4f99 | 719 | goto error; |
1da177e4 LT |
720 | } |
721 | ||
722 | if (euid != (uid_t) -1) { | |
a29c33f4 EB |
723 | new->euid = keuid; |
724 | if (!uid_eq(old->uid, keuid) && | |
725 | !uid_eq(old->euid, keuid) && | |
726 | !uid_eq(old->suid, keuid) && | |
fc832ad3 | 727 | !nsown_capable(CAP_SETUID)) |
d84f4f99 | 728 | goto error; |
1da177e4 LT |
729 | } |
730 | ||
a29c33f4 | 731 | if (!uid_eq(new->uid, old->uid)) { |
54e99124 DG |
732 | retval = set_user(new); |
733 | if (retval < 0) | |
734 | goto error; | |
735 | } | |
1da177e4 | 736 | if (ruid != (uid_t) -1 || |
a29c33f4 | 737 | (euid != (uid_t) -1 && !uid_eq(keuid, old->uid))) |
d84f4f99 DH |
738 | new->suid = new->euid; |
739 | new->fsuid = new->euid; | |
1da177e4 | 740 | |
d84f4f99 DH |
741 | retval = security_task_fix_setuid(new, old, LSM_SETID_RE); |
742 | if (retval < 0) | |
743 | goto error; | |
1da177e4 | 744 | |
d84f4f99 | 745 | return commit_creds(new); |
1da177e4 | 746 | |
d84f4f99 DH |
747 | error: |
748 | abort_creds(new); | |
749 | return retval; | |
750 | } | |
1da177e4 LT |
751 | |
752 | /* | |
753 | * setuid() is implemented like SysV with SAVED_IDS | |
754 | * | |
755 | * Note that SAVED_ID's is deficient in that a setuid root program | |
756 | * like sendmail, for example, cannot set its uid to be a normal | |
757 | * user and then switch back, because if you're root, setuid() sets | |
758 | * the saved uid too. If you don't like this, blame the bright people | |
759 | * in the POSIX committee and/or USG. Note that the BSD-style setreuid() | |
760 | * will allow a root program to temporarily drop privileges and be able to | |
761 | * regain them by swapping the real and effective uid. | |
762 | */ | |
ae1251ab | 763 | SYSCALL_DEFINE1(setuid, uid_t, uid) |
1da177e4 | 764 | { |
a29c33f4 | 765 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
766 | const struct cred *old; |
767 | struct cred *new; | |
1da177e4 | 768 | int retval; |
a29c33f4 EB |
769 | kuid_t kuid; |
770 | ||
771 | kuid = make_kuid(ns, uid); | |
772 | if (!uid_valid(kuid)) | |
773 | return -EINVAL; | |
1da177e4 | 774 | |
d84f4f99 DH |
775 | new = prepare_creds(); |
776 | if (!new) | |
777 | return -ENOMEM; | |
778 | old = current_cred(); | |
779 | ||
d84f4f99 | 780 | retval = -EPERM; |
fc832ad3 | 781 | if (nsown_capable(CAP_SETUID)) { |
a29c33f4 EB |
782 | new->suid = new->uid = kuid; |
783 | if (!uid_eq(kuid, old->uid)) { | |
54e99124 DG |
784 | retval = set_user(new); |
785 | if (retval < 0) | |
786 | goto error; | |
d84f4f99 | 787 | } |
a29c33f4 | 788 | } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) { |
d84f4f99 | 789 | goto error; |
1da177e4 | 790 | } |
1da177e4 | 791 | |
a29c33f4 | 792 | new->fsuid = new->euid = kuid; |
d84f4f99 DH |
793 | |
794 | retval = security_task_fix_setuid(new, old, LSM_SETID_ID); | |
795 | if (retval < 0) | |
796 | goto error; | |
1da177e4 | 797 | |
d84f4f99 | 798 | return commit_creds(new); |
1da177e4 | 799 | |
d84f4f99 DH |
800 | error: |
801 | abort_creds(new); | |
802 | return retval; | |
1da177e4 LT |
803 | } |
804 | ||
805 | ||
806 | /* | |
807 | * This function implements a generic ability to update ruid, euid, | |
808 | * and suid. This allows you to implement the 4.4 compatible seteuid(). | |
809 | */ | |
ae1251ab | 810 | SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) |
1da177e4 | 811 | { |
a29c33f4 | 812 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
813 | const struct cred *old; |
814 | struct cred *new; | |
1da177e4 | 815 | int retval; |
a29c33f4 EB |
816 | kuid_t kruid, keuid, ksuid; |
817 | ||
818 | kruid = make_kuid(ns, ruid); | |
819 | keuid = make_kuid(ns, euid); | |
820 | ksuid = make_kuid(ns, suid); | |
821 | ||
822 | if ((ruid != (uid_t) -1) && !uid_valid(kruid)) | |
823 | return -EINVAL; | |
824 | ||
825 | if ((euid != (uid_t) -1) && !uid_valid(keuid)) | |
826 | return -EINVAL; | |
827 | ||
828 | if ((suid != (uid_t) -1) && !uid_valid(ksuid)) | |
829 | return -EINVAL; | |
1da177e4 | 830 | |
d84f4f99 DH |
831 | new = prepare_creds(); |
832 | if (!new) | |
833 | return -ENOMEM; | |
834 | ||
d84f4f99 | 835 | old = current_cred(); |
1da177e4 | 836 | |
d84f4f99 | 837 | retval = -EPERM; |
fc832ad3 | 838 | if (!nsown_capable(CAP_SETUID)) { |
a29c33f4 EB |
839 | if (ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) && |
840 | !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid)) | |
d84f4f99 | 841 | goto error; |
a29c33f4 EB |
842 | if (euid != (uid_t) -1 && !uid_eq(keuid, old->uid) && |
843 | !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid)) | |
d84f4f99 | 844 | goto error; |
a29c33f4 EB |
845 | if (suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) && |
846 | !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid)) | |
d84f4f99 | 847 | goto error; |
1da177e4 | 848 | } |
d84f4f99 | 849 | |
1da177e4 | 850 | if (ruid != (uid_t) -1) { |
a29c33f4 EB |
851 | new->uid = kruid; |
852 | if (!uid_eq(kruid, old->uid)) { | |
54e99124 DG |
853 | retval = set_user(new); |
854 | if (retval < 0) | |
855 | goto error; | |
856 | } | |
1da177e4 | 857 | } |
d84f4f99 | 858 | if (euid != (uid_t) -1) |
a29c33f4 | 859 | new->euid = keuid; |
1da177e4 | 860 | if (suid != (uid_t) -1) |
a29c33f4 | 861 | new->suid = ksuid; |
d84f4f99 | 862 | new->fsuid = new->euid; |
1da177e4 | 863 | |
d84f4f99 DH |
864 | retval = security_task_fix_setuid(new, old, LSM_SETID_RES); |
865 | if (retval < 0) | |
866 | goto error; | |
1da177e4 | 867 | |
d84f4f99 | 868 | return commit_creds(new); |
1da177e4 | 869 | |
d84f4f99 DH |
870 | error: |
871 | abort_creds(new); | |
872 | return retval; | |
1da177e4 LT |
873 | } |
874 | ||
a29c33f4 | 875 | SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp) |
1da177e4 | 876 | { |
86a264ab | 877 | const struct cred *cred = current_cred(); |
1da177e4 | 878 | int retval; |
a29c33f4 EB |
879 | uid_t ruid, euid, suid; |
880 | ||
881 | ruid = from_kuid_munged(cred->user_ns, cred->uid); | |
882 | euid = from_kuid_munged(cred->user_ns, cred->euid); | |
883 | suid = from_kuid_munged(cred->user_ns, cred->suid); | |
1da177e4 | 884 | |
a29c33f4 EB |
885 | if (!(retval = put_user(ruid, ruidp)) && |
886 | !(retval = put_user(euid, euidp))) | |
887 | retval = put_user(suid, suidp); | |
1da177e4 LT |
888 | |
889 | return retval; | |
890 | } | |
891 | ||
892 | /* | |
893 | * Same as above, but for rgid, egid, sgid. | |
894 | */ | |
ae1251ab | 895 | SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) |
1da177e4 | 896 | { |
a29c33f4 | 897 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
898 | const struct cred *old; |
899 | struct cred *new; | |
1da177e4 | 900 | int retval; |
a29c33f4 EB |
901 | kgid_t krgid, kegid, ksgid; |
902 | ||
903 | krgid = make_kgid(ns, rgid); | |
904 | kegid = make_kgid(ns, egid); | |
905 | ksgid = make_kgid(ns, sgid); | |
906 | ||
907 | if ((rgid != (gid_t) -1) && !gid_valid(krgid)) | |
908 | return -EINVAL; | |
909 | if ((egid != (gid_t) -1) && !gid_valid(kegid)) | |
910 | return -EINVAL; | |
911 | if ((sgid != (gid_t) -1) && !gid_valid(ksgid)) | |
912 | return -EINVAL; | |
1da177e4 | 913 | |
d84f4f99 DH |
914 | new = prepare_creds(); |
915 | if (!new) | |
916 | return -ENOMEM; | |
917 | old = current_cred(); | |
918 | ||
d84f4f99 | 919 | retval = -EPERM; |
fc832ad3 | 920 | if (!nsown_capable(CAP_SETGID)) { |
a29c33f4 EB |
921 | if (rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) && |
922 | !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid)) | |
d84f4f99 | 923 | goto error; |
a29c33f4 EB |
924 | if (egid != (gid_t) -1 && !gid_eq(kegid, old->gid) && |
925 | !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid)) | |
d84f4f99 | 926 | goto error; |
a29c33f4 EB |
927 | if (sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) && |
928 | !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid)) | |
d84f4f99 | 929 | goto error; |
1da177e4 | 930 | } |
d84f4f99 | 931 | |
1da177e4 | 932 | if (rgid != (gid_t) -1) |
a29c33f4 | 933 | new->gid = krgid; |
d84f4f99 | 934 | if (egid != (gid_t) -1) |
a29c33f4 | 935 | new->egid = kegid; |
1da177e4 | 936 | if (sgid != (gid_t) -1) |
a29c33f4 | 937 | new->sgid = ksgid; |
d84f4f99 | 938 | new->fsgid = new->egid; |
1da177e4 | 939 | |
d84f4f99 DH |
940 | return commit_creds(new); |
941 | ||
942 | error: | |
943 | abort_creds(new); | |
944 | return retval; | |
1da177e4 LT |
945 | } |
946 | ||
a29c33f4 | 947 | SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp) |
1da177e4 | 948 | { |
86a264ab | 949 | const struct cred *cred = current_cred(); |
1da177e4 | 950 | int retval; |
a29c33f4 EB |
951 | gid_t rgid, egid, sgid; |
952 | ||
953 | rgid = from_kgid_munged(cred->user_ns, cred->gid); | |
954 | egid = from_kgid_munged(cred->user_ns, cred->egid); | |
955 | sgid = from_kgid_munged(cred->user_ns, cred->sgid); | |
1da177e4 | 956 | |
a29c33f4 EB |
957 | if (!(retval = put_user(rgid, rgidp)) && |
958 | !(retval = put_user(egid, egidp))) | |
959 | retval = put_user(sgid, sgidp); | |
1da177e4 LT |
960 | |
961 | return retval; | |
962 | } | |
963 | ||
964 | ||
965 | /* | |
966 | * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This | |
967 | * is used for "access()" and for the NFS daemon (letting nfsd stay at | |
968 | * whatever uid it wants to). It normally shadows "euid", except when | |
969 | * explicitly set by setfsuid() or for access.. | |
970 | */ | |
ae1251ab | 971 | SYSCALL_DEFINE1(setfsuid, uid_t, uid) |
1da177e4 | 972 | { |
d84f4f99 DH |
973 | const struct cred *old; |
974 | struct cred *new; | |
975 | uid_t old_fsuid; | |
a29c33f4 EB |
976 | kuid_t kuid; |
977 | ||
978 | old = current_cred(); | |
979 | old_fsuid = from_kuid_munged(old->user_ns, old->fsuid); | |
980 | ||
981 | kuid = make_kuid(old->user_ns, uid); | |
982 | if (!uid_valid(kuid)) | |
983 | return old_fsuid; | |
1da177e4 | 984 | |
d84f4f99 DH |
985 | new = prepare_creds(); |
986 | if (!new) | |
a29c33f4 | 987 | return old_fsuid; |
1da177e4 | 988 | |
a29c33f4 EB |
989 | if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) || |
990 | uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) || | |
fc832ad3 | 991 | nsown_capable(CAP_SETUID)) { |
a29c33f4 EB |
992 | if (!uid_eq(kuid, old->fsuid)) { |
993 | new->fsuid = kuid; | |
d84f4f99 DH |
994 | if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) |
995 | goto change_okay; | |
1da177e4 | 996 | } |
1da177e4 LT |
997 | } |
998 | ||
d84f4f99 DH |
999 | abort_creds(new); |
1000 | return old_fsuid; | |
1da177e4 | 1001 | |
d84f4f99 DH |
1002 | change_okay: |
1003 | commit_creds(new); | |
1da177e4 LT |
1004 | return old_fsuid; |
1005 | } | |
1006 | ||
1007 | /* | |
f42df9e6 | 1008 | * Samma på svenska.. |
1da177e4 | 1009 | */ |
ae1251ab | 1010 | SYSCALL_DEFINE1(setfsgid, gid_t, gid) |
1da177e4 | 1011 | { |
d84f4f99 DH |
1012 | const struct cred *old; |
1013 | struct cred *new; | |
1014 | gid_t old_fsgid; | |
a29c33f4 EB |
1015 | kgid_t kgid; |
1016 | ||
1017 | old = current_cred(); | |
1018 | old_fsgid = from_kgid_munged(old->user_ns, old->fsgid); | |
1019 | ||
1020 | kgid = make_kgid(old->user_ns, gid); | |
1021 | if (!gid_valid(kgid)) | |
1022 | return old_fsgid; | |
d84f4f99 DH |
1023 | |
1024 | new = prepare_creds(); | |
1025 | if (!new) | |
a29c33f4 | 1026 | return old_fsgid; |
1da177e4 | 1027 | |
a29c33f4 EB |
1028 | if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) || |
1029 | gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) || | |
fc832ad3 | 1030 | nsown_capable(CAP_SETGID)) { |
a29c33f4 EB |
1031 | if (!gid_eq(kgid, old->fsgid)) { |
1032 | new->fsgid = kgid; | |
d84f4f99 | 1033 | goto change_okay; |
1da177e4 | 1034 | } |
1da177e4 | 1035 | } |
d84f4f99 | 1036 | |
d84f4f99 DH |
1037 | abort_creds(new); |
1038 | return old_fsgid; | |
1039 | ||
1040 | change_okay: | |
1041 | commit_creds(new); | |
1da177e4 LT |
1042 | return old_fsgid; |
1043 | } | |
1044 | ||
f06febc9 FM |
1045 | void do_sys_times(struct tms *tms) |
1046 | { | |
0cf55e1e | 1047 | cputime_t tgutime, tgstime, cutime, cstime; |
f06febc9 | 1048 | |
2b5fe6de | 1049 | spin_lock_irq(¤t->sighand->siglock); |
e80d0a1a | 1050 | thread_group_cputime_adjusted(current, &tgutime, &tgstime); |
f06febc9 FM |
1051 | cutime = current->signal->cutime; |
1052 | cstime = current->signal->cstime; | |
1053 | spin_unlock_irq(¤t->sighand->siglock); | |
0cf55e1e HS |
1054 | tms->tms_utime = cputime_to_clock_t(tgutime); |
1055 | tms->tms_stime = cputime_to_clock_t(tgstime); | |
f06febc9 FM |
1056 | tms->tms_cutime = cputime_to_clock_t(cutime); |
1057 | tms->tms_cstime = cputime_to_clock_t(cstime); | |
1058 | } | |
1059 | ||
58fd3aa2 | 1060 | SYSCALL_DEFINE1(times, struct tms __user *, tbuf) |
1da177e4 | 1061 | { |
1da177e4 LT |
1062 | if (tbuf) { |
1063 | struct tms tmp; | |
f06febc9 FM |
1064 | |
1065 | do_sys_times(&tmp); | |
1da177e4 LT |
1066 | if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
1067 | return -EFAULT; | |
1068 | } | |
e3d5a27d | 1069 | force_successful_syscall_return(); |
1da177e4 LT |
1070 | return (long) jiffies_64_to_clock_t(get_jiffies_64()); |
1071 | } | |
1072 | ||
1073 | /* | |
1074 | * This needs some heavy checking ... | |
1075 | * I just haven't the stomach for it. I also don't fully | |
1076 | * understand sessions/pgrp etc. Let somebody who does explain it. | |
1077 | * | |
1078 | * OK, I think I have the protection semantics right.... this is really | |
1079 | * only important on a multi-user system anyway, to make sure one user | |
1080 | * can't send a signal to a process owned by another. -TYT, 12/12/91 | |
1081 | * | |
1082 | * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. | |
1083 | * LBT 04.03.94 | |
1084 | */ | |
b290ebe2 | 1085 | SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) |
1da177e4 LT |
1086 | { |
1087 | struct task_struct *p; | |
ee0acf90 | 1088 | struct task_struct *group_leader = current->group_leader; |
4e021306 ON |
1089 | struct pid *pgrp; |
1090 | int err; | |
1da177e4 LT |
1091 | |
1092 | if (!pid) | |
b488893a | 1093 | pid = task_pid_vnr(group_leader); |
1da177e4 LT |
1094 | if (!pgid) |
1095 | pgid = pid; | |
1096 | if (pgid < 0) | |
1097 | return -EINVAL; | |
950eaaca | 1098 | rcu_read_lock(); |
1da177e4 LT |
1099 | |
1100 | /* From this point forward we keep holding onto the tasklist lock | |
1101 | * so that our parent does not change from under us. -DaveM | |
1102 | */ | |
1103 | write_lock_irq(&tasklist_lock); | |
1104 | ||
1105 | err = -ESRCH; | |
4e021306 | 1106 | p = find_task_by_vpid(pid); |
1da177e4 LT |
1107 | if (!p) |
1108 | goto out; | |
1109 | ||
1110 | err = -EINVAL; | |
1111 | if (!thread_group_leader(p)) | |
1112 | goto out; | |
1113 | ||
4e021306 | 1114 | if (same_thread_group(p->real_parent, group_leader)) { |
1da177e4 | 1115 | err = -EPERM; |
41487c65 | 1116 | if (task_session(p) != task_session(group_leader)) |
1da177e4 LT |
1117 | goto out; |
1118 | err = -EACCES; | |
1119 | if (p->did_exec) | |
1120 | goto out; | |
1121 | } else { | |
1122 | err = -ESRCH; | |
ee0acf90 | 1123 | if (p != group_leader) |
1da177e4 LT |
1124 | goto out; |
1125 | } | |
1126 | ||
1127 | err = -EPERM; | |
1128 | if (p->signal->leader) | |
1129 | goto out; | |
1130 | ||
4e021306 | 1131 | pgrp = task_pid(p); |
1da177e4 | 1132 | if (pgid != pid) { |
b488893a | 1133 | struct task_struct *g; |
1da177e4 | 1134 | |
4e021306 ON |
1135 | pgrp = find_vpid(pgid); |
1136 | g = pid_task(pgrp, PIDTYPE_PGID); | |
41487c65 | 1137 | if (!g || task_session(g) != task_session(group_leader)) |
f020bc46 | 1138 | goto out; |
1da177e4 LT |
1139 | } |
1140 | ||
1da177e4 LT |
1141 | err = security_task_setpgid(p, pgid); |
1142 | if (err) | |
1143 | goto out; | |
1144 | ||
1b0f7ffd | 1145 | if (task_pgrp(p) != pgrp) |
83beaf3c | 1146 | change_pid(p, PIDTYPE_PGID, pgrp); |
1da177e4 LT |
1147 | |
1148 | err = 0; | |
1149 | out: | |
1150 | /* All paths lead to here, thus we are safe. -DaveM */ | |
1151 | write_unlock_irq(&tasklist_lock); | |
950eaaca | 1152 | rcu_read_unlock(); |
1da177e4 LT |
1153 | return err; |
1154 | } | |
1155 | ||
dbf040d9 | 1156 | SYSCALL_DEFINE1(getpgid, pid_t, pid) |
1da177e4 | 1157 | { |
12a3de0a ON |
1158 | struct task_struct *p; |
1159 | struct pid *grp; | |
1160 | int retval; | |
1161 | ||
1162 | rcu_read_lock(); | |
756184b7 | 1163 | if (!pid) |
12a3de0a | 1164 | grp = task_pgrp(current); |
756184b7 | 1165 | else { |
1da177e4 | 1166 | retval = -ESRCH; |
12a3de0a ON |
1167 | p = find_task_by_vpid(pid); |
1168 | if (!p) | |
1169 | goto out; | |
1170 | grp = task_pgrp(p); | |
1171 | if (!grp) | |
1172 | goto out; | |
1173 | ||
1174 | retval = security_task_getpgid(p); | |
1175 | if (retval) | |
1176 | goto out; | |
1da177e4 | 1177 | } |
12a3de0a ON |
1178 | retval = pid_vnr(grp); |
1179 | out: | |
1180 | rcu_read_unlock(); | |
1181 | return retval; | |
1da177e4 LT |
1182 | } |
1183 | ||
1184 | #ifdef __ARCH_WANT_SYS_GETPGRP | |
1185 | ||
dbf040d9 | 1186 | SYSCALL_DEFINE0(getpgrp) |
1da177e4 | 1187 | { |
12a3de0a | 1188 | return sys_getpgid(0); |
1da177e4 LT |
1189 | } |
1190 | ||
1191 | #endif | |
1192 | ||
dbf040d9 | 1193 | SYSCALL_DEFINE1(getsid, pid_t, pid) |
1da177e4 | 1194 | { |
1dd768c0 ON |
1195 | struct task_struct *p; |
1196 | struct pid *sid; | |
1197 | int retval; | |
1198 | ||
1199 | rcu_read_lock(); | |
756184b7 | 1200 | if (!pid) |
1dd768c0 | 1201 | sid = task_session(current); |
756184b7 | 1202 | else { |
1da177e4 | 1203 | retval = -ESRCH; |
1dd768c0 ON |
1204 | p = find_task_by_vpid(pid); |
1205 | if (!p) | |
1206 | goto out; | |
1207 | sid = task_session(p); | |
1208 | if (!sid) | |
1209 | goto out; | |
1210 | ||
1211 | retval = security_task_getsid(p); | |
1212 | if (retval) | |
1213 | goto out; | |
1da177e4 | 1214 | } |
1dd768c0 ON |
1215 | retval = pid_vnr(sid); |
1216 | out: | |
1217 | rcu_read_unlock(); | |
1218 | return retval; | |
1da177e4 LT |
1219 | } |
1220 | ||
b290ebe2 | 1221 | SYSCALL_DEFINE0(setsid) |
1da177e4 | 1222 | { |
e19f247a | 1223 | struct task_struct *group_leader = current->group_leader; |
e4cc0a9c ON |
1224 | struct pid *sid = task_pid(group_leader); |
1225 | pid_t session = pid_vnr(sid); | |
1da177e4 LT |
1226 | int err = -EPERM; |
1227 | ||
1da177e4 | 1228 | write_lock_irq(&tasklist_lock); |
390e2ff0 EB |
1229 | /* Fail if I am already a session leader */ |
1230 | if (group_leader->signal->leader) | |
1231 | goto out; | |
1232 | ||
430c6231 ON |
1233 | /* Fail if a process group id already exists that equals the |
1234 | * proposed session id. | |
390e2ff0 | 1235 | */ |
6806aac6 | 1236 | if (pid_task(sid, PIDTYPE_PGID)) |
1da177e4 LT |
1237 | goto out; |
1238 | ||
e19f247a | 1239 | group_leader->signal->leader = 1; |
8520d7c7 | 1240 | __set_special_pids(sid); |
24ec839c | 1241 | |
9c9f4ded | 1242 | proc_clear_tty(group_leader); |
24ec839c | 1243 | |
e4cc0a9c | 1244 | err = session; |
1da177e4 LT |
1245 | out: |
1246 | write_unlock_irq(&tasklist_lock); | |
5091faa4 | 1247 | if (err > 0) { |
0d0df599 | 1248 | proc_sid_connector(group_leader); |
5091faa4 MG |
1249 | sched_autogroup_create_attach(group_leader); |
1250 | } | |
1da177e4 LT |
1251 | return err; |
1252 | } | |
1253 | ||
1da177e4 LT |
1254 | DECLARE_RWSEM(uts_sem); |
1255 | ||
e28cbf22 CH |
1256 | #ifdef COMPAT_UTS_MACHINE |
1257 | #define override_architecture(name) \ | |
46da2766 | 1258 | (personality(current->personality) == PER_LINUX32 && \ |
e28cbf22 CH |
1259 | copy_to_user(name->machine, COMPAT_UTS_MACHINE, \ |
1260 | sizeof(COMPAT_UTS_MACHINE))) | |
1261 | #else | |
1262 | #define override_architecture(name) 0 | |
1263 | #endif | |
1264 | ||
be27425d AK |
1265 | /* |
1266 | * Work around broken programs that cannot handle "Linux 3.0". | |
1267 | * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40 | |
1268 | */ | |
2702b152 | 1269 | static int override_release(char __user *release, size_t len) |
be27425d AK |
1270 | { |
1271 | int ret = 0; | |
be27425d AK |
1272 | |
1273 | if (current->personality & UNAME26) { | |
2702b152 KC |
1274 | const char *rest = UTS_RELEASE; |
1275 | char buf[65] = { 0 }; | |
be27425d AK |
1276 | int ndots = 0; |
1277 | unsigned v; | |
2702b152 | 1278 | size_t copy; |
be27425d AK |
1279 | |
1280 | while (*rest) { | |
1281 | if (*rest == '.' && ++ndots >= 3) | |
1282 | break; | |
1283 | if (!isdigit(*rest) && *rest != '.') | |
1284 | break; | |
1285 | rest++; | |
1286 | } | |
1287 | v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 40; | |
31fd84b9 | 1288 | copy = clamp_t(size_t, len, 1, sizeof(buf)); |
2702b152 KC |
1289 | copy = scnprintf(buf, copy, "2.6.%u%s", v, rest); |
1290 | ret = copy_to_user(release, buf, copy + 1); | |
be27425d AK |
1291 | } |
1292 | return ret; | |
1293 | } | |
1294 | ||
e48fbb69 | 1295 | SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name) |
1da177e4 LT |
1296 | { |
1297 | int errno = 0; | |
1298 | ||
1299 | down_read(&uts_sem); | |
e9ff3990 | 1300 | if (copy_to_user(name, utsname(), sizeof *name)) |
1da177e4 LT |
1301 | errno = -EFAULT; |
1302 | up_read(&uts_sem); | |
e28cbf22 | 1303 | |
be27425d AK |
1304 | if (!errno && override_release(name->release, sizeof(name->release))) |
1305 | errno = -EFAULT; | |
e28cbf22 CH |
1306 | if (!errno && override_architecture(name)) |
1307 | errno = -EFAULT; | |
1da177e4 LT |
1308 | return errno; |
1309 | } | |
1310 | ||
5cacdb4a CH |
1311 | #ifdef __ARCH_WANT_SYS_OLD_UNAME |
1312 | /* | |
1313 | * Old cruft | |
1314 | */ | |
1315 | SYSCALL_DEFINE1(uname, struct old_utsname __user *, name) | |
1316 | { | |
1317 | int error = 0; | |
1318 | ||
1319 | if (!name) | |
1320 | return -EFAULT; | |
1321 | ||
1322 | down_read(&uts_sem); | |
1323 | if (copy_to_user(name, utsname(), sizeof(*name))) | |
1324 | error = -EFAULT; | |
1325 | up_read(&uts_sem); | |
1326 | ||
be27425d AK |
1327 | if (!error && override_release(name->release, sizeof(name->release))) |
1328 | error = -EFAULT; | |
5cacdb4a CH |
1329 | if (!error && override_architecture(name)) |
1330 | error = -EFAULT; | |
1331 | return error; | |
1332 | } | |
1333 | ||
1334 | SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name) | |
1335 | { | |
1336 | int error; | |
1337 | ||
1338 | if (!name) | |
1339 | return -EFAULT; | |
1340 | if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname))) | |
1341 | return -EFAULT; | |
1342 | ||
1343 | down_read(&uts_sem); | |
1344 | error = __copy_to_user(&name->sysname, &utsname()->sysname, | |
1345 | __OLD_UTS_LEN); | |
1346 | error |= __put_user(0, name->sysname + __OLD_UTS_LEN); | |
1347 | error |= __copy_to_user(&name->nodename, &utsname()->nodename, | |
1348 | __OLD_UTS_LEN); | |
1349 | error |= __put_user(0, name->nodename + __OLD_UTS_LEN); | |
1350 | error |= __copy_to_user(&name->release, &utsname()->release, | |
1351 | __OLD_UTS_LEN); | |
1352 | error |= __put_user(0, name->release + __OLD_UTS_LEN); | |
1353 | error |= __copy_to_user(&name->version, &utsname()->version, | |
1354 | __OLD_UTS_LEN); | |
1355 | error |= __put_user(0, name->version + __OLD_UTS_LEN); | |
1356 | error |= __copy_to_user(&name->machine, &utsname()->machine, | |
1357 | __OLD_UTS_LEN); | |
1358 | error |= __put_user(0, name->machine + __OLD_UTS_LEN); | |
1359 | up_read(&uts_sem); | |
1360 | ||
1361 | if (!error && override_architecture(name)) | |
1362 | error = -EFAULT; | |
be27425d AK |
1363 | if (!error && override_release(name->release, sizeof(name->release))) |
1364 | error = -EFAULT; | |
5cacdb4a CH |
1365 | return error ? -EFAULT : 0; |
1366 | } | |
1367 | #endif | |
1368 | ||
5a8a82b1 | 1369 | SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) |
1da177e4 LT |
1370 | { |
1371 | int errno; | |
1372 | char tmp[__NEW_UTS_LEN]; | |
1373 | ||
bb96a6f5 | 1374 | if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
1da177e4 | 1375 | return -EPERM; |
fc832ad3 | 1376 | |
1da177e4 LT |
1377 | if (len < 0 || len > __NEW_UTS_LEN) |
1378 | return -EINVAL; | |
1379 | down_write(&uts_sem); | |
1380 | errno = -EFAULT; | |
1381 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1382 | struct new_utsname *u = utsname(); |
1383 | ||
1384 | memcpy(u->nodename, tmp, len); | |
1385 | memset(u->nodename + len, 0, sizeof(u->nodename) - len); | |
1da177e4 | 1386 | errno = 0; |
499eea6b | 1387 | uts_proc_notify(UTS_PROC_HOSTNAME); |
1da177e4 LT |
1388 | } |
1389 | up_write(&uts_sem); | |
1390 | return errno; | |
1391 | } | |
1392 | ||
1393 | #ifdef __ARCH_WANT_SYS_GETHOSTNAME | |
1394 | ||
5a8a82b1 | 1395 | SYSCALL_DEFINE2(gethostname, char __user *, name, int, len) |
1da177e4 LT |
1396 | { |
1397 | int i, errno; | |
9679e4dd | 1398 | struct new_utsname *u; |
1da177e4 LT |
1399 | |
1400 | if (len < 0) | |
1401 | return -EINVAL; | |
1402 | down_read(&uts_sem); | |
9679e4dd AM |
1403 | u = utsname(); |
1404 | i = 1 + strlen(u->nodename); | |
1da177e4 LT |
1405 | if (i > len) |
1406 | i = len; | |
1407 | errno = 0; | |
9679e4dd | 1408 | if (copy_to_user(name, u->nodename, i)) |
1da177e4 LT |
1409 | errno = -EFAULT; |
1410 | up_read(&uts_sem); | |
1411 | return errno; | |
1412 | } | |
1413 | ||
1414 | #endif | |
1415 | ||
1416 | /* | |
1417 | * Only setdomainname; getdomainname can be implemented by calling | |
1418 | * uname() | |
1419 | */ | |
5a8a82b1 | 1420 | SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) |
1da177e4 LT |
1421 | { |
1422 | int errno; | |
1423 | char tmp[__NEW_UTS_LEN]; | |
1424 | ||
fc832ad3 | 1425 | if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
1da177e4 LT |
1426 | return -EPERM; |
1427 | if (len < 0 || len > __NEW_UTS_LEN) | |
1428 | return -EINVAL; | |
1429 | ||
1430 | down_write(&uts_sem); | |
1431 | errno = -EFAULT; | |
1432 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1433 | struct new_utsname *u = utsname(); |
1434 | ||
1435 | memcpy(u->domainname, tmp, len); | |
1436 | memset(u->domainname + len, 0, sizeof(u->domainname) - len); | |
1da177e4 | 1437 | errno = 0; |
499eea6b | 1438 | uts_proc_notify(UTS_PROC_DOMAINNAME); |
1da177e4 LT |
1439 | } |
1440 | up_write(&uts_sem); | |
1441 | return errno; | |
1442 | } | |
1443 | ||
e48fbb69 | 1444 | SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1da177e4 | 1445 | { |
b9518345 JS |
1446 | struct rlimit value; |
1447 | int ret; | |
1448 | ||
1449 | ret = do_prlimit(current, resource, NULL, &value); | |
1450 | if (!ret) | |
1451 | ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; | |
1452 | ||
1453 | return ret; | |
1da177e4 LT |
1454 | } |
1455 | ||
1456 | #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT | |
1457 | ||
1458 | /* | |
1459 | * Back compatibility for getrlimit. Needed for some apps. | |
1460 | */ | |
1461 | ||
e48fbb69 HC |
1462 | SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, |
1463 | struct rlimit __user *, rlim) | |
1da177e4 LT |
1464 | { |
1465 | struct rlimit x; | |
1466 | if (resource >= RLIM_NLIMITS) | |
1467 | return -EINVAL; | |
1468 | ||
1469 | task_lock(current->group_leader); | |
1470 | x = current->signal->rlim[resource]; | |
1471 | task_unlock(current->group_leader); | |
756184b7 | 1472 | if (x.rlim_cur > 0x7FFFFFFF) |
1da177e4 | 1473 | x.rlim_cur = 0x7FFFFFFF; |
756184b7 | 1474 | if (x.rlim_max > 0x7FFFFFFF) |
1da177e4 LT |
1475 | x.rlim_max = 0x7FFFFFFF; |
1476 | return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0; | |
1477 | } | |
1478 | ||
1479 | #endif | |
1480 | ||
c022a0ac JS |
1481 | static inline bool rlim64_is_infinity(__u64 rlim64) |
1482 | { | |
1483 | #if BITS_PER_LONG < 64 | |
1484 | return rlim64 >= ULONG_MAX; | |
1485 | #else | |
1486 | return rlim64 == RLIM64_INFINITY; | |
1487 | #endif | |
1488 | } | |
1489 | ||
1490 | static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64) | |
1491 | { | |
1492 | if (rlim->rlim_cur == RLIM_INFINITY) | |
1493 | rlim64->rlim_cur = RLIM64_INFINITY; | |
1494 | else | |
1495 | rlim64->rlim_cur = rlim->rlim_cur; | |
1496 | if (rlim->rlim_max == RLIM_INFINITY) | |
1497 | rlim64->rlim_max = RLIM64_INFINITY; | |
1498 | else | |
1499 | rlim64->rlim_max = rlim->rlim_max; | |
1500 | } | |
1501 | ||
1502 | static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim) | |
1503 | { | |
1504 | if (rlim64_is_infinity(rlim64->rlim_cur)) | |
1505 | rlim->rlim_cur = RLIM_INFINITY; | |
1506 | else | |
1507 | rlim->rlim_cur = (unsigned long)rlim64->rlim_cur; | |
1508 | if (rlim64_is_infinity(rlim64->rlim_max)) | |
1509 | rlim->rlim_max = RLIM_INFINITY; | |
1510 | else | |
1511 | rlim->rlim_max = (unsigned long)rlim64->rlim_max; | |
1512 | } | |
1513 | ||
1c1e618d | 1514 | /* make sure you are allowed to change @tsk limits before calling this */ |
5b41535a JS |
1515 | int do_prlimit(struct task_struct *tsk, unsigned int resource, |
1516 | struct rlimit *new_rlim, struct rlimit *old_rlim) | |
1da177e4 | 1517 | { |
5b41535a | 1518 | struct rlimit *rlim; |
86f162f4 | 1519 | int retval = 0; |
1da177e4 LT |
1520 | |
1521 | if (resource >= RLIM_NLIMITS) | |
1522 | return -EINVAL; | |
5b41535a JS |
1523 | if (new_rlim) { |
1524 | if (new_rlim->rlim_cur > new_rlim->rlim_max) | |
1525 | return -EINVAL; | |
1526 | if (resource == RLIMIT_NOFILE && | |
1527 | new_rlim->rlim_max > sysctl_nr_open) | |
1528 | return -EPERM; | |
1529 | } | |
1da177e4 | 1530 | |
1c1e618d JS |
1531 | /* protect tsk->signal and tsk->sighand from disappearing */ |
1532 | read_lock(&tasklist_lock); | |
1533 | if (!tsk->sighand) { | |
1534 | retval = -ESRCH; | |
1535 | goto out; | |
1536 | } | |
1537 | ||
5b41535a | 1538 | rlim = tsk->signal->rlim + resource; |
86f162f4 | 1539 | task_lock(tsk->group_leader); |
5b41535a | 1540 | if (new_rlim) { |
fc832ad3 SH |
1541 | /* Keep the capable check against init_user_ns until |
1542 | cgroups can contain all limits */ | |
5b41535a JS |
1543 | if (new_rlim->rlim_max > rlim->rlim_max && |
1544 | !capable(CAP_SYS_RESOURCE)) | |
1545 | retval = -EPERM; | |
1546 | if (!retval) | |
1547 | retval = security_task_setrlimit(tsk->group_leader, | |
1548 | resource, new_rlim); | |
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 | } | |
1559 | if (!retval) { | |
1560 | if (old_rlim) | |
1561 | *old_rlim = *rlim; | |
1562 | if (new_rlim) | |
1563 | *rlim = *new_rlim; | |
9926e4c7 | 1564 | } |
7855c35d | 1565 | task_unlock(tsk->group_leader); |
1da177e4 | 1566 | |
d3561f78 AM |
1567 | /* |
1568 | * RLIMIT_CPU handling. Note that the kernel fails to return an error | |
1569 | * code if it rejected the user's attempt to set RLIMIT_CPU. This is a | |
1570 | * very long-standing error, and fixing it now risks breakage of | |
1571 | * applications, so we live with it | |
1572 | */ | |
5b41535a JS |
1573 | if (!retval && new_rlim && resource == RLIMIT_CPU && |
1574 | new_rlim->rlim_cur != RLIM_INFINITY) | |
1575 | update_rlimit_cpu(tsk, new_rlim->rlim_cur); | |
ec9e16ba | 1576 | out: |
1c1e618d | 1577 | read_unlock(&tasklist_lock); |
2fb9d268 | 1578 | return retval; |
1da177e4 LT |
1579 | } |
1580 | ||
c022a0ac JS |
1581 | /* rcu lock must be held */ |
1582 | static int check_prlimit_permission(struct task_struct *task) | |
1583 | { | |
1584 | const struct cred *cred = current_cred(), *tcred; | |
1585 | ||
fc832ad3 SH |
1586 | if (current == task) |
1587 | return 0; | |
c022a0ac | 1588 | |
fc832ad3 | 1589 | tcred = __task_cred(task); |
5af66203 EB |
1590 | if (uid_eq(cred->uid, tcred->euid) && |
1591 | uid_eq(cred->uid, tcred->suid) && | |
1592 | uid_eq(cred->uid, tcred->uid) && | |
1593 | gid_eq(cred->gid, tcred->egid) && | |
1594 | gid_eq(cred->gid, tcred->sgid) && | |
1595 | gid_eq(cred->gid, tcred->gid)) | |
fc832ad3 | 1596 | return 0; |
c4a4d603 | 1597 | if (ns_capable(tcred->user_ns, CAP_SYS_RESOURCE)) |
fc832ad3 SH |
1598 | return 0; |
1599 | ||
1600 | return -EPERM; | |
c022a0ac JS |
1601 | } |
1602 | ||
1603 | SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource, | |
1604 | const struct rlimit64 __user *, new_rlim, | |
1605 | struct rlimit64 __user *, old_rlim) | |
1606 | { | |
1607 | struct rlimit64 old64, new64; | |
1608 | struct rlimit old, new; | |
1609 | struct task_struct *tsk; | |
1610 | int ret; | |
1611 | ||
1612 | if (new_rlim) { | |
1613 | if (copy_from_user(&new64, new_rlim, sizeof(new64))) | |
1614 | return -EFAULT; | |
1615 | rlim64_to_rlim(&new64, &new); | |
1616 | } | |
1617 | ||
1618 | rcu_read_lock(); | |
1619 | tsk = pid ? find_task_by_vpid(pid) : current; | |
1620 | if (!tsk) { | |
1621 | rcu_read_unlock(); | |
1622 | return -ESRCH; | |
1623 | } | |
1624 | ret = check_prlimit_permission(tsk); | |
1625 | if (ret) { | |
1626 | rcu_read_unlock(); | |
1627 | return ret; | |
1628 | } | |
1629 | get_task_struct(tsk); | |
1630 | rcu_read_unlock(); | |
1631 | ||
1632 | ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL, | |
1633 | old_rlim ? &old : NULL); | |
1634 | ||
1635 | if (!ret && old_rlim) { | |
1636 | rlim_to_rlim64(&old, &old64); | |
1637 | if (copy_to_user(old_rlim, &old64, sizeof(old64))) | |
1638 | ret = -EFAULT; | |
1639 | } | |
1640 | ||
1641 | put_task_struct(tsk); | |
1642 | return ret; | |
1643 | } | |
1644 | ||
7855c35d JS |
1645 | SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1646 | { | |
1647 | struct rlimit new_rlim; | |
1648 | ||
1649 | if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) | |
1650 | return -EFAULT; | |
5b41535a | 1651 | return do_prlimit(current, resource, &new_rlim, NULL); |
7855c35d JS |
1652 | } |
1653 | ||
1da177e4 LT |
1654 | /* |
1655 | * It would make sense to put struct rusage in the task_struct, | |
1656 | * except that would make the task_struct be *really big*. After | |
1657 | * task_struct gets moved into malloc'ed memory, it would | |
1658 | * make sense to do this. It will make moving the rest of the information | |
1659 | * a lot simpler! (Which we're not doing right now because we're not | |
1660 | * measuring them yet). | |
1661 | * | |
1da177e4 LT |
1662 | * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
1663 | * races with threads incrementing their own counters. But since word | |
1664 | * reads are atomic, we either get new values or old values and we don't | |
1665 | * care which for the sums. We always take the siglock to protect reading | |
1666 | * the c* fields from p->signal from races with exit.c updating those | |
1667 | * fields when reaping, so a sample either gets all the additions of a | |
1668 | * given child after it's reaped, or none so this sample is before reaping. | |
2dd0ebcd | 1669 | * |
de047c1b RT |
1670 | * Locking: |
1671 | * We need to take the siglock for CHILDEREN, SELF and BOTH | |
1672 | * for the cases current multithreaded, non-current single threaded | |
1673 | * non-current multithreaded. Thread traversal is now safe with | |
1674 | * the siglock held. | |
1675 | * Strictly speaking, we donot need to take the siglock if we are current and | |
1676 | * single threaded, as no one else can take our signal_struct away, no one | |
1677 | * else can reap the children to update signal->c* counters, and no one else | |
1678 | * can race with the signal-> fields. If we do not take any lock, the | |
1679 | * signal-> fields could be read out of order while another thread was just | |
1680 | * exiting. So we should place a read memory barrier when we avoid the lock. | |
1681 | * On the writer side, write memory barrier is implied in __exit_signal | |
1682 | * as __exit_signal releases the siglock spinlock after updating the signal-> | |
1683 | * fields. But we don't do this yet to keep things simple. | |
2dd0ebcd | 1684 | * |
1da177e4 LT |
1685 | */ |
1686 | ||
f06febc9 | 1687 | static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) |
679c9cd4 | 1688 | { |
679c9cd4 SK |
1689 | r->ru_nvcsw += t->nvcsw; |
1690 | r->ru_nivcsw += t->nivcsw; | |
1691 | r->ru_minflt += t->min_flt; | |
1692 | r->ru_majflt += t->maj_flt; | |
1693 | r->ru_inblock += task_io_get_inblock(t); | |
1694 | r->ru_oublock += task_io_get_oublock(t); | |
1695 | } | |
1696 | ||
1da177e4 LT |
1697 | static void k_getrusage(struct task_struct *p, int who, struct rusage *r) |
1698 | { | |
1699 | struct task_struct *t; | |
1700 | unsigned long flags; | |
0cf55e1e | 1701 | cputime_t tgutime, tgstime, utime, stime; |
1f10206c | 1702 | unsigned long maxrss = 0; |
1da177e4 LT |
1703 | |
1704 | memset((char *) r, 0, sizeof *r); | |
64861634 | 1705 | utime = stime = 0; |
1da177e4 | 1706 | |
679c9cd4 | 1707 | if (who == RUSAGE_THREAD) { |
e80d0a1a | 1708 | task_cputime_adjusted(current, &utime, &stime); |
f06febc9 | 1709 | accumulate_thread_rusage(p, r); |
1f10206c | 1710 | maxrss = p->signal->maxrss; |
679c9cd4 SK |
1711 | goto out; |
1712 | } | |
1713 | ||
d6cf723a | 1714 | if (!lock_task_sighand(p, &flags)) |
de047c1b | 1715 | return; |
0f59cc4a | 1716 | |
1da177e4 | 1717 | switch (who) { |
0f59cc4a | 1718 | case RUSAGE_BOTH: |
1da177e4 | 1719 | case RUSAGE_CHILDREN: |
1da177e4 LT |
1720 | utime = p->signal->cutime; |
1721 | stime = p->signal->cstime; | |
1722 | r->ru_nvcsw = p->signal->cnvcsw; | |
1723 | r->ru_nivcsw = p->signal->cnivcsw; | |
1724 | r->ru_minflt = p->signal->cmin_flt; | |
1725 | r->ru_majflt = p->signal->cmaj_flt; | |
6eaeeaba ED |
1726 | r->ru_inblock = p->signal->cinblock; |
1727 | r->ru_oublock = p->signal->coublock; | |
1f10206c | 1728 | maxrss = p->signal->cmaxrss; |
0f59cc4a ON |
1729 | |
1730 | if (who == RUSAGE_CHILDREN) | |
1731 | break; | |
1732 | ||
1da177e4 | 1733 | case RUSAGE_SELF: |
e80d0a1a | 1734 | thread_group_cputime_adjusted(p, &tgutime, &tgstime); |
64861634 MS |
1735 | utime += tgutime; |
1736 | stime += tgstime; | |
1da177e4 LT |
1737 | r->ru_nvcsw += p->signal->nvcsw; |
1738 | r->ru_nivcsw += p->signal->nivcsw; | |
1739 | r->ru_minflt += p->signal->min_flt; | |
1740 | r->ru_majflt += p->signal->maj_flt; | |
6eaeeaba ED |
1741 | r->ru_inblock += p->signal->inblock; |
1742 | r->ru_oublock += p->signal->oublock; | |
1f10206c JP |
1743 | if (maxrss < p->signal->maxrss) |
1744 | maxrss = p->signal->maxrss; | |
1da177e4 LT |
1745 | t = p; |
1746 | do { | |
f06febc9 | 1747 | accumulate_thread_rusage(t, r); |
1da177e4 LT |
1748 | t = next_thread(t); |
1749 | } while (t != p); | |
1da177e4 | 1750 | break; |
0f59cc4a | 1751 | |
1da177e4 LT |
1752 | default: |
1753 | BUG(); | |
1754 | } | |
de047c1b | 1755 | unlock_task_sighand(p, &flags); |
de047c1b | 1756 | |
679c9cd4 | 1757 | out: |
0f59cc4a ON |
1758 | cputime_to_timeval(utime, &r->ru_utime); |
1759 | cputime_to_timeval(stime, &r->ru_stime); | |
1f10206c JP |
1760 | |
1761 | if (who != RUSAGE_CHILDREN) { | |
1762 | struct mm_struct *mm = get_task_mm(p); | |
1763 | if (mm) { | |
1764 | setmax_mm_hiwater_rss(&maxrss, mm); | |
1765 | mmput(mm); | |
1766 | } | |
1767 | } | |
1768 | r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */ | |
1da177e4 LT |
1769 | } |
1770 | ||
1771 | int getrusage(struct task_struct *p, int who, struct rusage __user *ru) | |
1772 | { | |
1773 | struct rusage r; | |
1da177e4 | 1774 | k_getrusage(p, who, &r); |
1da177e4 LT |
1775 | return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
1776 | } | |
1777 | ||
e48fbb69 | 1778 | SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) |
1da177e4 | 1779 | { |
679c9cd4 SK |
1780 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
1781 | who != RUSAGE_THREAD) | |
1da177e4 LT |
1782 | return -EINVAL; |
1783 | return getrusage(current, who, ru); | |
1784 | } | |
1785 | ||
e48fbb69 | 1786 | SYSCALL_DEFINE1(umask, int, mask) |
1da177e4 LT |
1787 | { |
1788 | mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); | |
1789 | return mask; | |
1790 | } | |
3b7391de | 1791 | |
028ee4be | 1792 | #ifdef CONFIG_CHECKPOINT_RESTORE |
b32dfe37 CG |
1793 | static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd) |
1794 | { | |
2903ff01 | 1795 | struct fd exe; |
b32dfe37 | 1796 | struct dentry *dentry; |
2903ff01 | 1797 | int err; |
b32dfe37 | 1798 | |
2903ff01 AV |
1799 | exe = fdget(fd); |
1800 | if (!exe.file) | |
b32dfe37 CG |
1801 | return -EBADF; |
1802 | ||
2903ff01 | 1803 | dentry = exe.file->f_path.dentry; |
b32dfe37 CG |
1804 | |
1805 | /* | |
1806 | * Because the original mm->exe_file points to executable file, make | |
1807 | * sure that this one is executable as well, to avoid breaking an | |
1808 | * overall picture. | |
1809 | */ | |
1810 | err = -EACCES; | |
1811 | if (!S_ISREG(dentry->d_inode->i_mode) || | |
2903ff01 | 1812 | exe.file->f_path.mnt->mnt_flags & MNT_NOEXEC) |
b32dfe37 CG |
1813 | goto exit; |
1814 | ||
1815 | err = inode_permission(dentry->d_inode, MAY_EXEC); | |
1816 | if (err) | |
1817 | goto exit; | |
1818 | ||
bafb282d KK |
1819 | down_write(&mm->mmap_sem); |
1820 | ||
1821 | /* | |
4229fb1d | 1822 | * Forbid mm->exe_file change if old file still mapped. |
bafb282d KK |
1823 | */ |
1824 | err = -EBUSY; | |
4229fb1d KK |
1825 | if (mm->exe_file) { |
1826 | struct vm_area_struct *vma; | |
1827 | ||
1828 | for (vma = mm->mmap; vma; vma = vma->vm_next) | |
1829 | if (vma->vm_file && | |
1830 | path_equal(&vma->vm_file->f_path, | |
1831 | &mm->exe_file->f_path)) | |
1832 | goto exit_unlock; | |
bafb282d KK |
1833 | } |
1834 | ||
b32dfe37 CG |
1835 | /* |
1836 | * The symlink can be changed only once, just to disallow arbitrary | |
1837 | * transitions malicious software might bring in. This means one | |
1838 | * could make a snapshot over all processes running and monitor | |
1839 | * /proc/pid/exe changes to notice unusual activity if needed. | |
1840 | */ | |
bafb282d KK |
1841 | err = -EPERM; |
1842 | if (test_and_set_bit(MMF_EXE_FILE_CHANGED, &mm->flags)) | |
1843 | goto exit_unlock; | |
1844 | ||
4229fb1d | 1845 | err = 0; |
2903ff01 | 1846 | set_mm_exe_file(mm, exe.file); /* this grabs a reference to exe.file */ |
bafb282d | 1847 | exit_unlock: |
b32dfe37 CG |
1848 | up_write(&mm->mmap_sem); |
1849 | ||
1850 | exit: | |
2903ff01 | 1851 | fdput(exe); |
b32dfe37 CG |
1852 | return err; |
1853 | } | |
1854 | ||
028ee4be CG |
1855 | static int prctl_set_mm(int opt, unsigned long addr, |
1856 | unsigned long arg4, unsigned long arg5) | |
1857 | { | |
1858 | unsigned long rlim = rlimit(RLIMIT_DATA); | |
028ee4be | 1859 | struct mm_struct *mm = current->mm; |
fe8c7f5c CG |
1860 | struct vm_area_struct *vma; |
1861 | int error; | |
028ee4be | 1862 | |
fe8c7f5c | 1863 | if (arg5 || (arg4 && opt != PR_SET_MM_AUXV)) |
028ee4be CG |
1864 | return -EINVAL; |
1865 | ||
79f0713d | 1866 | if (!capable(CAP_SYS_RESOURCE)) |
028ee4be CG |
1867 | return -EPERM; |
1868 | ||
b32dfe37 CG |
1869 | if (opt == PR_SET_MM_EXE_FILE) |
1870 | return prctl_set_mm_exe_file(mm, (unsigned int)addr); | |
1871 | ||
1ad75b9e | 1872 | if (addr >= TASK_SIZE || addr < mmap_min_addr) |
028ee4be CG |
1873 | return -EINVAL; |
1874 | ||
fe8c7f5c CG |
1875 | error = -EINVAL; |
1876 | ||
028ee4be CG |
1877 | down_read(&mm->mmap_sem); |
1878 | vma = find_vma(mm, addr); | |
1879 | ||
028ee4be CG |
1880 | switch (opt) { |
1881 | case PR_SET_MM_START_CODE: | |
fe8c7f5c CG |
1882 | mm->start_code = addr; |
1883 | break; | |
028ee4be | 1884 | case PR_SET_MM_END_CODE: |
fe8c7f5c | 1885 | mm->end_code = addr; |
028ee4be | 1886 | break; |
028ee4be | 1887 | case PR_SET_MM_START_DATA: |
fe8c7f5c | 1888 | mm->start_data = addr; |
028ee4be | 1889 | break; |
fe8c7f5c CG |
1890 | case PR_SET_MM_END_DATA: |
1891 | mm->end_data = addr; | |
028ee4be CG |
1892 | break; |
1893 | ||
1894 | case PR_SET_MM_START_BRK: | |
1895 | if (addr <= mm->end_data) | |
1896 | goto out; | |
1897 | ||
1898 | if (rlim < RLIM_INFINITY && | |
1899 | (mm->brk - addr) + | |
1900 | (mm->end_data - mm->start_data) > rlim) | |
1901 | goto out; | |
1902 | ||
1903 | mm->start_brk = addr; | |
1904 | break; | |
1905 | ||
1906 | case PR_SET_MM_BRK: | |
1907 | if (addr <= mm->end_data) | |
1908 | goto out; | |
1909 | ||
1910 | if (rlim < RLIM_INFINITY && | |
1911 | (addr - mm->start_brk) + | |
1912 | (mm->end_data - mm->start_data) > rlim) | |
1913 | goto out; | |
1914 | ||
1915 | mm->brk = addr; | |
1916 | break; | |
1917 | ||
fe8c7f5c CG |
1918 | /* |
1919 | * If command line arguments and environment | |
1920 | * are placed somewhere else on stack, we can | |
1921 | * set them up here, ARG_START/END to setup | |
1922 | * command line argumets and ENV_START/END | |
1923 | * for environment. | |
1924 | */ | |
1925 | case PR_SET_MM_START_STACK: | |
1926 | case PR_SET_MM_ARG_START: | |
1927 | case PR_SET_MM_ARG_END: | |
1928 | case PR_SET_MM_ENV_START: | |
1929 | case PR_SET_MM_ENV_END: | |
1930 | if (!vma) { | |
1931 | error = -EFAULT; | |
1932 | goto out; | |
1933 | } | |
fe8c7f5c CG |
1934 | if (opt == PR_SET_MM_START_STACK) |
1935 | mm->start_stack = addr; | |
1936 | else if (opt == PR_SET_MM_ARG_START) | |
1937 | mm->arg_start = addr; | |
1938 | else if (opt == PR_SET_MM_ARG_END) | |
1939 | mm->arg_end = addr; | |
1940 | else if (opt == PR_SET_MM_ENV_START) | |
1941 | mm->env_start = addr; | |
1942 | else if (opt == PR_SET_MM_ENV_END) | |
1943 | mm->env_end = addr; | |
1944 | break; | |
1945 | ||
1946 | /* | |
1947 | * This doesn't move auxiliary vector itself | |
1948 | * since it's pinned to mm_struct, but allow | |
1949 | * to fill vector with new values. It's up | |
1950 | * to a caller to provide sane values here | |
1951 | * otherwise user space tools which use this | |
1952 | * vector might be unhappy. | |
1953 | */ | |
1954 | case PR_SET_MM_AUXV: { | |
1955 | unsigned long user_auxv[AT_VECTOR_SIZE]; | |
1956 | ||
1957 | if (arg4 > sizeof(user_auxv)) | |
1958 | goto out; | |
1959 | up_read(&mm->mmap_sem); | |
1960 | ||
1961 | if (copy_from_user(user_auxv, (const void __user *)addr, arg4)) | |
1962 | return -EFAULT; | |
1963 | ||
1964 | /* Make sure the last entry is always AT_NULL */ | |
1965 | user_auxv[AT_VECTOR_SIZE - 2] = 0; | |
1966 | user_auxv[AT_VECTOR_SIZE - 1] = 0; | |
1967 | ||
1968 | BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); | |
1969 | ||
1970 | task_lock(current); | |
1971 | memcpy(mm->saved_auxv, user_auxv, arg4); | |
1972 | task_unlock(current); | |
1973 | ||
1974 | return 0; | |
1975 | } | |
028ee4be | 1976 | default: |
028ee4be CG |
1977 | goto out; |
1978 | } | |
1979 | ||
1980 | error = 0; | |
028ee4be CG |
1981 | out: |
1982 | up_read(&mm->mmap_sem); | |
028ee4be CG |
1983 | return error; |
1984 | } | |
300f786b CG |
1985 | |
1986 | static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr) | |
1987 | { | |
1988 | return put_user(me->clear_child_tid, tid_addr); | |
1989 | } | |
1990 | ||
028ee4be CG |
1991 | #else /* CONFIG_CHECKPOINT_RESTORE */ |
1992 | static int prctl_set_mm(int opt, unsigned long addr, | |
1993 | unsigned long arg4, unsigned long arg5) | |
1994 | { | |
1995 | return -EINVAL; | |
1996 | } | |
300f786b CG |
1997 | static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr) |
1998 | { | |
1999 | return -EINVAL; | |
2000 | } | |
028ee4be CG |
2001 | #endif |
2002 | ||
c4ea37c2 HC |
2003 | SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, |
2004 | unsigned long, arg4, unsigned long, arg5) | |
1da177e4 | 2005 | { |
b6dff3ec DH |
2006 | struct task_struct *me = current; |
2007 | unsigned char comm[sizeof(me->comm)]; | |
2008 | long error; | |
1da177e4 | 2009 | |
d84f4f99 DH |
2010 | error = security_task_prctl(option, arg2, arg3, arg4, arg5); |
2011 | if (error != -ENOSYS) | |
1da177e4 LT |
2012 | return error; |
2013 | ||
d84f4f99 | 2014 | error = 0; |
1da177e4 | 2015 | switch (option) { |
f3cbd435 AM |
2016 | case PR_SET_PDEATHSIG: |
2017 | if (!valid_signal(arg2)) { | |
2018 | error = -EINVAL; | |
1da177e4 | 2019 | break; |
f3cbd435 AM |
2020 | } |
2021 | me->pdeath_signal = arg2; | |
2022 | break; | |
2023 | case PR_GET_PDEATHSIG: | |
2024 | error = put_user(me->pdeath_signal, (int __user *)arg2); | |
2025 | break; | |
2026 | case PR_GET_DUMPABLE: | |
2027 | error = get_dumpable(me->mm); | |
2028 | break; | |
2029 | case PR_SET_DUMPABLE: | |
2030 | if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) { | |
2031 | error = -EINVAL; | |
1da177e4 | 2032 | break; |
f3cbd435 AM |
2033 | } |
2034 | set_dumpable(me->mm, arg2); | |
2035 | break; | |
1da177e4 | 2036 | |
f3cbd435 AM |
2037 | case PR_SET_UNALIGN: |
2038 | error = SET_UNALIGN_CTL(me, arg2); | |
2039 | break; | |
2040 | case PR_GET_UNALIGN: | |
2041 | error = GET_UNALIGN_CTL(me, arg2); | |
2042 | break; | |
2043 | case PR_SET_FPEMU: | |
2044 | error = SET_FPEMU_CTL(me, arg2); | |
2045 | break; | |
2046 | case PR_GET_FPEMU: | |
2047 | error = GET_FPEMU_CTL(me, arg2); | |
2048 | break; | |
2049 | case PR_SET_FPEXC: | |
2050 | error = SET_FPEXC_CTL(me, arg2); | |
2051 | break; | |
2052 | case PR_GET_FPEXC: | |
2053 | error = GET_FPEXC_CTL(me, arg2); | |
2054 | break; | |
2055 | case PR_GET_TIMING: | |
2056 | error = PR_TIMING_STATISTICAL; | |
2057 | break; | |
2058 | case PR_SET_TIMING: | |
2059 | if (arg2 != PR_TIMING_STATISTICAL) | |
2060 | error = -EINVAL; | |
2061 | break; | |
2062 | case PR_SET_NAME: | |
2063 | comm[sizeof(me->comm) - 1] = 0; | |
2064 | if (strncpy_from_user(comm, (char __user *)arg2, | |
2065 | sizeof(me->comm) - 1) < 0) | |
2066 | return -EFAULT; | |
2067 | set_task_comm(me, comm); | |
2068 | proc_comm_connector(me); | |
2069 | break; | |
2070 | case PR_GET_NAME: | |
2071 | get_task_comm(comm, me); | |
2072 | if (copy_to_user((char __user *)arg2, comm, sizeof(comm))) | |
2073 | return -EFAULT; | |
2074 | break; | |
2075 | case PR_GET_ENDIAN: | |
2076 | error = GET_ENDIAN(me, arg2); | |
2077 | break; | |
2078 | case PR_SET_ENDIAN: | |
2079 | error = SET_ENDIAN(me, arg2); | |
2080 | break; | |
2081 | case PR_GET_SECCOMP: | |
2082 | error = prctl_get_seccomp(); | |
2083 | break; | |
2084 | case PR_SET_SECCOMP: | |
2085 | error = prctl_set_seccomp(arg2, (char __user *)arg3); | |
2086 | break; | |
2087 | case PR_GET_TSC: | |
2088 | error = GET_TSC_CTL(arg2); | |
2089 | break; | |
2090 | case PR_SET_TSC: | |
2091 | error = SET_TSC_CTL(arg2); | |
2092 | break; | |
2093 | case PR_TASK_PERF_EVENTS_DISABLE: | |
2094 | error = perf_event_task_disable(); | |
2095 | break; | |
2096 | case PR_TASK_PERF_EVENTS_ENABLE: | |
2097 | error = perf_event_task_enable(); | |
2098 | break; | |
2099 | case PR_GET_TIMERSLACK: | |
2100 | error = current->timer_slack_ns; | |
2101 | break; | |
2102 | case PR_SET_TIMERSLACK: | |
2103 | if (arg2 <= 0) | |
2104 | current->timer_slack_ns = | |
6976675d | 2105 | current->default_timer_slack_ns; |
f3cbd435 AM |
2106 | else |
2107 | current->timer_slack_ns = arg2; | |
2108 | break; | |
2109 | case PR_MCE_KILL: | |
2110 | if (arg4 | arg5) | |
2111 | return -EINVAL; | |
2112 | switch (arg2) { | |
2113 | case PR_MCE_KILL_CLEAR: | |
2114 | if (arg3 != 0) | |
4db96cf0 | 2115 | return -EINVAL; |
f3cbd435 | 2116 | current->flags &= ~PF_MCE_PROCESS; |
4db96cf0 | 2117 | break; |
f3cbd435 AM |
2118 | case PR_MCE_KILL_SET: |
2119 | current->flags |= PF_MCE_PROCESS; | |
2120 | if (arg3 == PR_MCE_KILL_EARLY) | |
2121 | current->flags |= PF_MCE_EARLY; | |
2122 | else if (arg3 == PR_MCE_KILL_LATE) | |
2123 | current->flags &= ~PF_MCE_EARLY; | |
2124 | else if (arg3 == PR_MCE_KILL_DEFAULT) | |
2125 | current->flags &= | |
2126 | ~(PF_MCE_EARLY|PF_MCE_PROCESS); | |
1087e9b4 | 2127 | else |
259e5e6c | 2128 | return -EINVAL; |
259e5e6c | 2129 | break; |
1da177e4 | 2130 | default: |
f3cbd435 AM |
2131 | return -EINVAL; |
2132 | } | |
2133 | break; | |
2134 | case PR_MCE_KILL_GET: | |
2135 | if (arg2 | arg3 | arg4 | arg5) | |
2136 | return -EINVAL; | |
2137 | if (current->flags & PF_MCE_PROCESS) | |
2138 | error = (current->flags & PF_MCE_EARLY) ? | |
2139 | PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE; | |
2140 | else | |
2141 | error = PR_MCE_KILL_DEFAULT; | |
2142 | break; | |
2143 | case PR_SET_MM: | |
2144 | error = prctl_set_mm(arg2, arg3, arg4, arg5); | |
2145 | break; | |
2146 | case PR_GET_TID_ADDRESS: | |
2147 | error = prctl_get_tid_address(me, (int __user **)arg2); | |
2148 | break; | |
2149 | case PR_SET_CHILD_SUBREAPER: | |
2150 | me->signal->is_child_subreaper = !!arg2; | |
2151 | break; | |
2152 | case PR_GET_CHILD_SUBREAPER: | |
2153 | error = put_user(me->signal->is_child_subreaper, | |
2154 | (int __user *)arg2); | |
2155 | break; | |
2156 | case PR_SET_NO_NEW_PRIVS: | |
2157 | if (arg2 != 1 || arg3 || arg4 || arg5) | |
2158 | return -EINVAL; | |
2159 | ||
2160 | current->no_new_privs = 1; | |
2161 | break; | |
2162 | case PR_GET_NO_NEW_PRIVS: | |
2163 | if (arg2 || arg3 || arg4 || arg5) | |
2164 | return -EINVAL; | |
2165 | return current->no_new_privs ? 1 : 0; | |
2166 | default: | |
2167 | error = -EINVAL; | |
2168 | break; | |
1da177e4 LT |
2169 | } |
2170 | return error; | |
2171 | } | |
3cfc348b | 2172 | |
836f92ad HC |
2173 | SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep, |
2174 | struct getcpu_cache __user *, unused) | |
3cfc348b AK |
2175 | { |
2176 | int err = 0; | |
2177 | int cpu = raw_smp_processor_id(); | |
2178 | if (cpup) | |
2179 | err |= put_user(cpu, cpup); | |
2180 | if (nodep) | |
2181 | err |= put_user(cpu_to_node(cpu), nodep); | |
3cfc348b AK |
2182 | return err ? -EFAULT : 0; |
2183 | } | |
10a0a8d4 JF |
2184 | |
2185 | char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff"; | |
2186 | ||
a06a4dc3 | 2187 | static void argv_cleanup(struct subprocess_info *info) |
10a0a8d4 | 2188 | { |
a06a4dc3 | 2189 | argv_free(info->argv); |
10a0a8d4 JF |
2190 | } |
2191 | ||
b57b44ae | 2192 | static int __orderly_poweroff(void) |
10a0a8d4 JF |
2193 | { |
2194 | int argc; | |
b57b44ae | 2195 | char **argv; |
10a0a8d4 JF |
2196 | static char *envp[] = { |
2197 | "HOME=/", | |
2198 | "PATH=/sbin:/bin:/usr/sbin:/usr/bin", | |
2199 | NULL | |
2200 | }; | |
b57b44ae | 2201 | int ret; |
10a0a8d4 | 2202 | |
b57b44ae | 2203 | argv = argv_split(GFP_ATOMIC, poweroff_cmd, &argc); |
10a0a8d4 JF |
2204 | if (argv == NULL) { |
2205 | printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n", | |
2206 | __func__, poweroff_cmd); | |
b57b44ae | 2207 | return -ENOMEM; |
10a0a8d4 JF |
2208 | } |
2209 | ||
6c0c0d4d | 2210 | ret = call_usermodehelper_fns(argv[0], argv, envp, UMH_WAIT_EXEC, |
81ab6e7b | 2211 | NULL, argv_cleanup, NULL); |
81ab6e7b BH |
2212 | if (ret == -ENOMEM) |
2213 | argv_free(argv); | |
10a0a8d4 | 2214 | |
b57b44ae AM |
2215 | return ret; |
2216 | } | |
2217 | ||
2218 | /** | |
2219 | * orderly_poweroff - Trigger an orderly system poweroff | |
2220 | * @force: force poweroff if command execution fails | |
2221 | * | |
2222 | * This may be called from any context to trigger a system shutdown. | |
2223 | * If the orderly shutdown fails, it will force an immediate shutdown. | |
2224 | */ | |
2225 | int orderly_poweroff(bool force) | |
2226 | { | |
2227 | int ret = __orderly_poweroff(); | |
2228 | ||
2229 | if (ret && force) { | |
10a0a8d4 JF |
2230 | printk(KERN_WARNING "Failed to start orderly shutdown: " |
2231 | "forcing the issue\n"); | |
2232 | ||
b57b44ae AM |
2233 | /* |
2234 | * I guess this should try to kick off some daemon to sync and | |
2235 | * poweroff asap. Or not even bother syncing if we're doing an | |
2236 | * emergency shutdown? | |
2237 | */ | |
10a0a8d4 JF |
2238 | emergency_sync(); |
2239 | kernel_power_off(); | |
2240 | } | |
2241 | ||
2242 | return ret; | |
2243 | } | |
2244 | EXPORT_SYMBOL_GPL(orderly_poweroff); |