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 | 18 | #include <linux/kernel.h> |
1da177e4 | 19 | #include <linux/workqueue.h> |
c59ede7b | 20 | #include <linux/capability.h> |
1da177e4 LT |
21 | #include <linux/device.h> |
22 | #include <linux/key.h> | |
23 | #include <linux/times.h> | |
24 | #include <linux/posix-timers.h> | |
25 | #include <linux/security.h> | |
26 | #include <linux/dcookies.h> | |
27 | #include <linux/suspend.h> | |
28 | #include <linux/tty.h> | |
7ed20e1a | 29 | #include <linux/signal.h> |
9f46080c | 30 | #include <linux/cn_proc.h> |
3cfc348b | 31 | #include <linux/getcpu.h> |
6eaeeaba | 32 | #include <linux/task_io_accounting_ops.h> |
1d9d02fe | 33 | #include <linux/seccomp.h> |
4047727e | 34 | #include <linux/cpu.h> |
e28cbf22 | 35 | #include <linux/personality.h> |
e3d5a27d | 36 | #include <linux/ptrace.h> |
5ad4e53b | 37 | #include <linux/fs_struct.h> |
b32dfe37 CG |
38 | #include <linux/file.h> |
39 | #include <linux/mount.h> | |
5a0e3ad6 | 40 | #include <linux/gfp.h> |
40dc166c | 41 | #include <linux/syscore_ops.h> |
be27425d AK |
42 | #include <linux/version.h> |
43 | #include <linux/ctype.h> | |
1da177e4 LT |
44 | |
45 | #include <linux/compat.h> | |
46 | #include <linux/syscalls.h> | |
00d7c05a | 47 | #include <linux/kprobes.h> |
acce292c | 48 | #include <linux/user_namespace.h> |
7fe5e042 | 49 | #include <linux/binfmts.h> |
1da177e4 | 50 | |
4a22f166 SR |
51 | #include <linux/sched.h> |
52 | #include <linux/rcupdate.h> | |
53 | #include <linux/uidgid.h> | |
54 | #include <linux/cred.h> | |
55 | ||
04c6862c | 56 | #include <linux/kmsg_dump.h> |
be27425d AK |
57 | /* Move somewhere else to avoid recompiling? */ |
58 | #include <generated/utsrelease.h> | |
04c6862c | 59 | |
1da177e4 LT |
60 | #include <asm/uaccess.h> |
61 | #include <asm/io.h> | |
62 | #include <asm/unistd.h> | |
63 | ||
64 | #ifndef SET_UNALIGN_CTL | |
ec94fc3d | 65 | # define SET_UNALIGN_CTL(a, b) (-EINVAL) |
1da177e4 LT |
66 | #endif |
67 | #ifndef GET_UNALIGN_CTL | |
ec94fc3d | 68 | # define GET_UNALIGN_CTL(a, b) (-EINVAL) |
1da177e4 LT |
69 | #endif |
70 | #ifndef SET_FPEMU_CTL | |
ec94fc3d | 71 | # define SET_FPEMU_CTL(a, b) (-EINVAL) |
1da177e4 LT |
72 | #endif |
73 | #ifndef GET_FPEMU_CTL | |
ec94fc3d | 74 | # define GET_FPEMU_CTL(a, b) (-EINVAL) |
1da177e4 LT |
75 | #endif |
76 | #ifndef SET_FPEXC_CTL | |
ec94fc3d | 77 | # define SET_FPEXC_CTL(a, b) (-EINVAL) |
1da177e4 LT |
78 | #endif |
79 | #ifndef GET_FPEXC_CTL | |
ec94fc3d | 80 | # define GET_FPEXC_CTL(a, b) (-EINVAL) |
1da177e4 | 81 | #endif |
651d765d | 82 | #ifndef GET_ENDIAN |
ec94fc3d | 83 | # define GET_ENDIAN(a, b) (-EINVAL) |
651d765d AB |
84 | #endif |
85 | #ifndef SET_ENDIAN | |
ec94fc3d | 86 | # define SET_ENDIAN(a, b) (-EINVAL) |
651d765d | 87 | #endif |
8fb402bc EB |
88 | #ifndef GET_TSC_CTL |
89 | # define GET_TSC_CTL(a) (-EINVAL) | |
90 | #endif | |
91 | #ifndef SET_TSC_CTL | |
92 | # define SET_TSC_CTL(a) (-EINVAL) | |
93 | #endif | |
1da177e4 LT |
94 | |
95 | /* | |
96 | * this is where the system-wide overflow UID and GID are defined, for | |
97 | * architectures that now have 32-bit UID/GID but didn't in the past | |
98 | */ | |
99 | ||
100 | int overflowuid = DEFAULT_OVERFLOWUID; | |
101 | int overflowgid = DEFAULT_OVERFLOWGID; | |
102 | ||
1da177e4 LT |
103 | EXPORT_SYMBOL(overflowuid); |
104 | EXPORT_SYMBOL(overflowgid); | |
1da177e4 LT |
105 | |
106 | /* | |
107 | * the same as above, but for filesystems which can only store a 16-bit | |
108 | * UID and GID. as such, this is needed on all architectures | |
109 | */ | |
110 | ||
111 | int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; | |
112 | int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; | |
113 | ||
114 | EXPORT_SYMBOL(fs_overflowuid); | |
115 | EXPORT_SYMBOL(fs_overflowgid); | |
116 | ||
fc832ad3 SH |
117 | /* |
118 | * Returns true if current's euid is same as p's uid or euid, | |
119 | * or has CAP_SYS_NICE to p's user_ns. | |
120 | * | |
121 | * Called with rcu_read_lock, creds are safe | |
122 | */ | |
123 | static bool set_one_prio_perm(struct task_struct *p) | |
124 | { | |
125 | const struct cred *cred = current_cred(), *pcred = __task_cred(p); | |
126 | ||
5af66203 EB |
127 | if (uid_eq(pcred->uid, cred->euid) || |
128 | uid_eq(pcred->euid, cred->euid)) | |
fc832ad3 | 129 | return true; |
c4a4d603 | 130 | if (ns_capable(pcred->user_ns, CAP_SYS_NICE)) |
fc832ad3 SH |
131 | return true; |
132 | return false; | |
133 | } | |
134 | ||
c69e8d9c DH |
135 | /* |
136 | * set the priority of a task | |
137 | * - the caller must hold the RCU read lock | |
138 | */ | |
1da177e4 LT |
139 | static int set_one_prio(struct task_struct *p, int niceval, int error) |
140 | { | |
141 | int no_nice; | |
142 | ||
fc832ad3 | 143 | if (!set_one_prio_perm(p)) { |
1da177e4 LT |
144 | error = -EPERM; |
145 | goto out; | |
146 | } | |
e43379f1 | 147 | if (niceval < task_nice(p) && !can_nice(p, niceval)) { |
1da177e4 LT |
148 | error = -EACCES; |
149 | goto out; | |
150 | } | |
151 | no_nice = security_task_setnice(p, niceval); | |
152 | if (no_nice) { | |
153 | error = no_nice; | |
154 | goto out; | |
155 | } | |
156 | if (error == -ESRCH) | |
157 | error = 0; | |
158 | set_user_nice(p, niceval); | |
159 | out: | |
160 | return error; | |
161 | } | |
162 | ||
754fe8d2 | 163 | SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval) |
1da177e4 LT |
164 | { |
165 | struct task_struct *g, *p; | |
166 | struct user_struct *user; | |
86a264ab | 167 | const struct cred *cred = current_cred(); |
1da177e4 | 168 | int error = -EINVAL; |
41487c65 | 169 | struct pid *pgrp; |
7b44ab97 | 170 | kuid_t uid; |
1da177e4 | 171 | |
3e88c553 | 172 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
173 | goto out; |
174 | ||
175 | /* normalize: avoid signed division (rounding problems) */ | |
176 | error = -ESRCH; | |
c4a4d2f4 DY |
177 | if (niceval < MIN_NICE) |
178 | niceval = MIN_NICE; | |
179 | if (niceval > MAX_NICE) | |
180 | niceval = MAX_NICE; | |
1da177e4 | 181 | |
d4581a23 | 182 | rcu_read_lock(); |
1da177e4 LT |
183 | read_lock(&tasklist_lock); |
184 | switch (which) { | |
ec94fc3d | 185 | case PRIO_PROCESS: |
186 | if (who) | |
187 | p = find_task_by_vpid(who); | |
188 | else | |
189 | p = current; | |
190 | if (p) | |
191 | error = set_one_prio(p, niceval, error); | |
192 | break; | |
193 | case PRIO_PGRP: | |
194 | if (who) | |
195 | pgrp = find_vpid(who); | |
196 | else | |
197 | pgrp = task_pgrp(current); | |
198 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { | |
199 | error = set_one_prio(p, niceval, error); | |
200 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); | |
201 | break; | |
202 | case PRIO_USER: | |
203 | uid = make_kuid(cred->user_ns, who); | |
204 | user = cred->user; | |
205 | if (!who) | |
206 | uid = cred->uid; | |
207 | else if (!uid_eq(uid, cred->uid)) { | |
208 | user = find_user(uid); | |
209 | if (!user) | |
86a264ab | 210 | goto out_unlock; /* No processes for this user */ |
ec94fc3d | 211 | } |
212 | do_each_thread(g, p) { | |
213 | if (uid_eq(task_uid(p), uid)) | |
214 | error = set_one_prio(p, niceval, error); | |
215 | } while_each_thread(g, p); | |
216 | if (!uid_eq(uid, cred->uid)) | |
217 | free_uid(user); /* For find_user() */ | |
218 | break; | |
1da177e4 LT |
219 | } |
220 | out_unlock: | |
221 | read_unlock(&tasklist_lock); | |
d4581a23 | 222 | rcu_read_unlock(); |
1da177e4 LT |
223 | out: |
224 | return error; | |
225 | } | |
226 | ||
227 | /* | |
228 | * Ugh. To avoid negative return values, "getpriority()" will | |
229 | * not return the normal nice-value, but a negated value that | |
230 | * has been offset by 20 (ie it returns 40..1 instead of -20..19) | |
231 | * to stay compatible. | |
232 | */ | |
754fe8d2 | 233 | SYSCALL_DEFINE2(getpriority, int, which, int, who) |
1da177e4 LT |
234 | { |
235 | struct task_struct *g, *p; | |
236 | struct user_struct *user; | |
86a264ab | 237 | const struct cred *cred = current_cred(); |
1da177e4 | 238 | long niceval, retval = -ESRCH; |
41487c65 | 239 | struct pid *pgrp; |
7b44ab97 | 240 | kuid_t uid; |
1da177e4 | 241 | |
3e88c553 | 242 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
243 | return -EINVAL; |
244 | ||
70118837 | 245 | rcu_read_lock(); |
1da177e4 LT |
246 | read_lock(&tasklist_lock); |
247 | switch (which) { | |
ec94fc3d | 248 | case PRIO_PROCESS: |
249 | if (who) | |
250 | p = find_task_by_vpid(who); | |
251 | else | |
252 | p = current; | |
253 | if (p) { | |
254 | niceval = nice_to_rlimit(task_nice(p)); | |
255 | if (niceval > retval) | |
256 | retval = niceval; | |
257 | } | |
258 | break; | |
259 | case PRIO_PGRP: | |
260 | if (who) | |
261 | pgrp = find_vpid(who); | |
262 | else | |
263 | pgrp = task_pgrp(current); | |
264 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { | |
265 | niceval = nice_to_rlimit(task_nice(p)); | |
266 | if (niceval > retval) | |
267 | retval = niceval; | |
268 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); | |
269 | break; | |
270 | case PRIO_USER: | |
271 | uid = make_kuid(cred->user_ns, who); | |
272 | user = cred->user; | |
273 | if (!who) | |
274 | uid = cred->uid; | |
275 | else if (!uid_eq(uid, cred->uid)) { | |
276 | user = find_user(uid); | |
277 | if (!user) | |
278 | goto out_unlock; /* No processes for this user */ | |
279 | } | |
280 | do_each_thread(g, p) { | |
281 | if (uid_eq(task_uid(p), uid)) { | |
7aa2c016 | 282 | niceval = nice_to_rlimit(task_nice(p)); |
1da177e4 LT |
283 | if (niceval > retval) |
284 | retval = niceval; | |
285 | } | |
ec94fc3d | 286 | } while_each_thread(g, p); |
287 | if (!uid_eq(uid, cred->uid)) | |
288 | free_uid(user); /* for find_user() */ | |
289 | break; | |
1da177e4 LT |
290 | } |
291 | out_unlock: | |
292 | read_unlock(&tasklist_lock); | |
70118837 | 293 | rcu_read_unlock(); |
1da177e4 LT |
294 | |
295 | return retval; | |
296 | } | |
297 | ||
1da177e4 LT |
298 | /* |
299 | * Unprivileged users may change the real gid to the effective gid | |
300 | * or vice versa. (BSD-style) | |
301 | * | |
302 | * If you set the real gid at all, or set the effective gid to a value not | |
303 | * equal to the real gid, then the saved gid is set to the new effective gid. | |
304 | * | |
305 | * This makes it possible for a setgid program to completely drop its | |
306 | * privileges, which is often a useful assertion to make when you are doing | |
307 | * a security audit over a program. | |
308 | * | |
309 | * The general idea is that a program which uses just setregid() will be | |
310 | * 100% compatible with BSD. A program which uses just setgid() will be | |
ec94fc3d | 311 | * 100% compatible with POSIX with saved IDs. |
1da177e4 LT |
312 | * |
313 | * SMP: There are not races, the GIDs are checked only by filesystem | |
314 | * operations (as far as semantic preservation is concerned). | |
315 | */ | |
ae1251ab | 316 | SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) |
1da177e4 | 317 | { |
a29c33f4 | 318 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
319 | const struct cred *old; |
320 | struct cred *new; | |
1da177e4 | 321 | int retval; |
a29c33f4 EB |
322 | kgid_t krgid, kegid; |
323 | ||
324 | krgid = make_kgid(ns, rgid); | |
325 | kegid = make_kgid(ns, egid); | |
326 | ||
327 | if ((rgid != (gid_t) -1) && !gid_valid(krgid)) | |
328 | return -EINVAL; | |
329 | if ((egid != (gid_t) -1) && !gid_valid(kegid)) | |
330 | return -EINVAL; | |
1da177e4 | 331 | |
d84f4f99 DH |
332 | new = prepare_creds(); |
333 | if (!new) | |
334 | return -ENOMEM; | |
335 | old = current_cred(); | |
336 | ||
d84f4f99 | 337 | retval = -EPERM; |
1da177e4 | 338 | if (rgid != (gid_t) -1) { |
a29c33f4 EB |
339 | if (gid_eq(old->gid, krgid) || |
340 | gid_eq(old->egid, krgid) || | |
c7b96acf | 341 | ns_capable(old->user_ns, CAP_SETGID)) |
a29c33f4 | 342 | new->gid = krgid; |
1da177e4 | 343 | else |
d84f4f99 | 344 | goto error; |
1da177e4 LT |
345 | } |
346 | if (egid != (gid_t) -1) { | |
a29c33f4 EB |
347 | if (gid_eq(old->gid, kegid) || |
348 | gid_eq(old->egid, kegid) || | |
349 | gid_eq(old->sgid, kegid) || | |
c7b96acf | 350 | ns_capable(old->user_ns, CAP_SETGID)) |
a29c33f4 | 351 | new->egid = kegid; |
756184b7 | 352 | else |
d84f4f99 | 353 | goto error; |
1da177e4 | 354 | } |
d84f4f99 | 355 | |
1da177e4 | 356 | if (rgid != (gid_t) -1 || |
a29c33f4 | 357 | (egid != (gid_t) -1 && !gid_eq(kegid, old->gid))) |
d84f4f99 DH |
358 | new->sgid = new->egid; |
359 | new->fsgid = new->egid; | |
360 | ||
361 | return commit_creds(new); | |
362 | ||
363 | error: | |
364 | abort_creds(new); | |
365 | return retval; | |
1da177e4 LT |
366 | } |
367 | ||
368 | /* | |
ec94fc3d | 369 | * setgid() is implemented like SysV w/ SAVED_IDS |
1da177e4 LT |
370 | * |
371 | * SMP: Same implicit races as above. | |
372 | */ | |
ae1251ab | 373 | SYSCALL_DEFINE1(setgid, gid_t, gid) |
1da177e4 | 374 | { |
a29c33f4 | 375 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
376 | const struct cred *old; |
377 | struct cred *new; | |
1da177e4 | 378 | int retval; |
a29c33f4 EB |
379 | kgid_t kgid; |
380 | ||
381 | kgid = make_kgid(ns, gid); | |
382 | if (!gid_valid(kgid)) | |
383 | return -EINVAL; | |
1da177e4 | 384 | |
d84f4f99 DH |
385 | new = prepare_creds(); |
386 | if (!new) | |
387 | return -ENOMEM; | |
388 | old = current_cred(); | |
389 | ||
d84f4f99 | 390 | retval = -EPERM; |
c7b96acf | 391 | if (ns_capable(old->user_ns, CAP_SETGID)) |
a29c33f4 EB |
392 | new->gid = new->egid = new->sgid = new->fsgid = kgid; |
393 | else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid)) | |
394 | new->egid = new->fsgid = kgid; | |
1da177e4 | 395 | else |
d84f4f99 | 396 | goto error; |
1da177e4 | 397 | |
d84f4f99 DH |
398 | return commit_creds(new); |
399 | ||
400 | error: | |
401 | abort_creds(new); | |
402 | return retval; | |
1da177e4 | 403 | } |
54e99124 | 404 | |
d84f4f99 DH |
405 | /* |
406 | * change the user struct in a credentials set to match the new UID | |
407 | */ | |
408 | static int set_user(struct cred *new) | |
1da177e4 LT |
409 | { |
410 | struct user_struct *new_user; | |
411 | ||
078de5f7 | 412 | new_user = alloc_uid(new->uid); |
1da177e4 LT |
413 | if (!new_user) |
414 | return -EAGAIN; | |
415 | ||
72fa5997 VK |
416 | /* |
417 | * We don't fail in case of NPROC limit excess here because too many | |
418 | * poorly written programs don't check set*uid() return code, assuming | |
419 | * it never fails if called by root. We may still enforce NPROC limit | |
420 | * for programs doing set*uid()+execve() by harmlessly deferring the | |
421 | * failure to the execve() stage. | |
422 | */ | |
78d7d407 | 423 | if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) && |
72fa5997 VK |
424 | new_user != INIT_USER) |
425 | current->flags |= PF_NPROC_EXCEEDED; | |
426 | else | |
427 | current->flags &= ~PF_NPROC_EXCEEDED; | |
1da177e4 | 428 | |
d84f4f99 DH |
429 | free_uid(new->user); |
430 | new->user = new_user; | |
1da177e4 LT |
431 | return 0; |
432 | } | |
433 | ||
434 | /* | |
435 | * Unprivileged users may change the real uid to the effective uid | |
436 | * or vice versa. (BSD-style) | |
437 | * | |
438 | * If you set the real uid at all, or set the effective uid to a value not | |
439 | * equal to the real uid, then the saved uid is set to the new effective uid. | |
440 | * | |
441 | * This makes it possible for a setuid program to completely drop its | |
442 | * privileges, which is often a useful assertion to make when you are doing | |
443 | * a security audit over a program. | |
444 | * | |
445 | * The general idea is that a program which uses just setreuid() will be | |
446 | * 100% compatible with BSD. A program which uses just setuid() will be | |
ec94fc3d | 447 | * 100% compatible with POSIX with saved IDs. |
1da177e4 | 448 | */ |
ae1251ab | 449 | SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) |
1da177e4 | 450 | { |
a29c33f4 | 451 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
452 | const struct cred *old; |
453 | struct cred *new; | |
1da177e4 | 454 | int retval; |
a29c33f4 EB |
455 | kuid_t kruid, keuid; |
456 | ||
457 | kruid = make_kuid(ns, ruid); | |
458 | keuid = make_kuid(ns, euid); | |
459 | ||
460 | if ((ruid != (uid_t) -1) && !uid_valid(kruid)) | |
461 | return -EINVAL; | |
462 | if ((euid != (uid_t) -1) && !uid_valid(keuid)) | |
463 | return -EINVAL; | |
1da177e4 | 464 | |
d84f4f99 DH |
465 | new = prepare_creds(); |
466 | if (!new) | |
467 | return -ENOMEM; | |
468 | old = current_cred(); | |
469 | ||
d84f4f99 | 470 | retval = -EPERM; |
1da177e4 | 471 | if (ruid != (uid_t) -1) { |
a29c33f4 EB |
472 | new->uid = kruid; |
473 | if (!uid_eq(old->uid, kruid) && | |
474 | !uid_eq(old->euid, kruid) && | |
c7b96acf | 475 | !ns_capable(old->user_ns, CAP_SETUID)) |
d84f4f99 | 476 | goto error; |
1da177e4 LT |
477 | } |
478 | ||
479 | if (euid != (uid_t) -1) { | |
a29c33f4 EB |
480 | new->euid = keuid; |
481 | if (!uid_eq(old->uid, keuid) && | |
482 | !uid_eq(old->euid, keuid) && | |
483 | !uid_eq(old->suid, keuid) && | |
c7b96acf | 484 | !ns_capable(old->user_ns, CAP_SETUID)) |
d84f4f99 | 485 | goto error; |
1da177e4 LT |
486 | } |
487 | ||
a29c33f4 | 488 | if (!uid_eq(new->uid, old->uid)) { |
54e99124 DG |
489 | retval = set_user(new); |
490 | if (retval < 0) | |
491 | goto error; | |
492 | } | |
1da177e4 | 493 | if (ruid != (uid_t) -1 || |
a29c33f4 | 494 | (euid != (uid_t) -1 && !uid_eq(keuid, old->uid))) |
d84f4f99 DH |
495 | new->suid = new->euid; |
496 | new->fsuid = new->euid; | |
1da177e4 | 497 | |
d84f4f99 DH |
498 | retval = security_task_fix_setuid(new, old, LSM_SETID_RE); |
499 | if (retval < 0) | |
500 | goto error; | |
1da177e4 | 501 | |
d84f4f99 | 502 | return commit_creds(new); |
1da177e4 | 503 | |
d84f4f99 DH |
504 | error: |
505 | abort_creds(new); | |
506 | return retval; | |
507 | } | |
ec94fc3d | 508 | |
1da177e4 | 509 | /* |
ec94fc3d | 510 | * setuid() is implemented like SysV with SAVED_IDS |
511 | * | |
1da177e4 | 512 | * Note that SAVED_ID's is deficient in that a setuid root program |
ec94fc3d | 513 | * like sendmail, for example, cannot set its uid to be a normal |
1da177e4 LT |
514 | * user and then switch back, because if you're root, setuid() sets |
515 | * the saved uid too. If you don't like this, blame the bright people | |
516 | * in the POSIX committee and/or USG. Note that the BSD-style setreuid() | |
517 | * will allow a root program to temporarily drop privileges and be able to | |
ec94fc3d | 518 | * regain them by swapping the real and effective uid. |
1da177e4 | 519 | */ |
ae1251ab | 520 | SYSCALL_DEFINE1(setuid, uid_t, uid) |
1da177e4 | 521 | { |
a29c33f4 | 522 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
523 | const struct cred *old; |
524 | struct cred *new; | |
1da177e4 | 525 | int retval; |
a29c33f4 EB |
526 | kuid_t kuid; |
527 | ||
528 | kuid = make_kuid(ns, uid); | |
529 | if (!uid_valid(kuid)) | |
530 | return -EINVAL; | |
1da177e4 | 531 | |
d84f4f99 DH |
532 | new = prepare_creds(); |
533 | if (!new) | |
534 | return -ENOMEM; | |
535 | old = current_cred(); | |
536 | ||
d84f4f99 | 537 | retval = -EPERM; |
c7b96acf | 538 | if (ns_capable(old->user_ns, CAP_SETUID)) { |
a29c33f4 EB |
539 | new->suid = new->uid = kuid; |
540 | if (!uid_eq(kuid, old->uid)) { | |
54e99124 DG |
541 | retval = set_user(new); |
542 | if (retval < 0) | |
543 | goto error; | |
d84f4f99 | 544 | } |
a29c33f4 | 545 | } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) { |
d84f4f99 | 546 | goto error; |
1da177e4 | 547 | } |
1da177e4 | 548 | |
a29c33f4 | 549 | new->fsuid = new->euid = kuid; |
d84f4f99 DH |
550 | |
551 | retval = security_task_fix_setuid(new, old, LSM_SETID_ID); | |
552 | if (retval < 0) | |
553 | goto error; | |
1da177e4 | 554 | |
d84f4f99 | 555 | return commit_creds(new); |
1da177e4 | 556 | |
d84f4f99 DH |
557 | error: |
558 | abort_creds(new); | |
559 | return retval; | |
1da177e4 LT |
560 | } |
561 | ||
562 | ||
563 | /* | |
564 | * This function implements a generic ability to update ruid, euid, | |
565 | * and suid. This allows you to implement the 4.4 compatible seteuid(). | |
566 | */ | |
ae1251ab | 567 | SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) |
1da177e4 | 568 | { |
a29c33f4 | 569 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
570 | const struct cred *old; |
571 | struct cred *new; | |
1da177e4 | 572 | int retval; |
a29c33f4 EB |
573 | kuid_t kruid, keuid, ksuid; |
574 | ||
575 | kruid = make_kuid(ns, ruid); | |
576 | keuid = make_kuid(ns, euid); | |
577 | ksuid = make_kuid(ns, suid); | |
578 | ||
579 | if ((ruid != (uid_t) -1) && !uid_valid(kruid)) | |
580 | return -EINVAL; | |
581 | ||
582 | if ((euid != (uid_t) -1) && !uid_valid(keuid)) | |
583 | return -EINVAL; | |
584 | ||
585 | if ((suid != (uid_t) -1) && !uid_valid(ksuid)) | |
586 | return -EINVAL; | |
1da177e4 | 587 | |
d84f4f99 DH |
588 | new = prepare_creds(); |
589 | if (!new) | |
590 | return -ENOMEM; | |
591 | ||
d84f4f99 | 592 | old = current_cred(); |
1da177e4 | 593 | |
d84f4f99 | 594 | retval = -EPERM; |
c7b96acf | 595 | if (!ns_capable(old->user_ns, CAP_SETUID)) { |
a29c33f4 EB |
596 | if (ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) && |
597 | !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid)) | |
d84f4f99 | 598 | goto error; |
a29c33f4 EB |
599 | if (euid != (uid_t) -1 && !uid_eq(keuid, old->uid) && |
600 | !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid)) | |
d84f4f99 | 601 | goto error; |
a29c33f4 EB |
602 | if (suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) && |
603 | !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid)) | |
d84f4f99 | 604 | goto error; |
1da177e4 | 605 | } |
d84f4f99 | 606 | |
1da177e4 | 607 | if (ruid != (uid_t) -1) { |
a29c33f4 EB |
608 | new->uid = kruid; |
609 | if (!uid_eq(kruid, old->uid)) { | |
54e99124 DG |
610 | retval = set_user(new); |
611 | if (retval < 0) | |
612 | goto error; | |
613 | } | |
1da177e4 | 614 | } |
d84f4f99 | 615 | if (euid != (uid_t) -1) |
a29c33f4 | 616 | new->euid = keuid; |
1da177e4 | 617 | if (suid != (uid_t) -1) |
a29c33f4 | 618 | new->suid = ksuid; |
d84f4f99 | 619 | new->fsuid = new->euid; |
1da177e4 | 620 | |
d84f4f99 DH |
621 | retval = security_task_fix_setuid(new, old, LSM_SETID_RES); |
622 | if (retval < 0) | |
623 | goto error; | |
1da177e4 | 624 | |
d84f4f99 | 625 | return commit_creds(new); |
1da177e4 | 626 | |
d84f4f99 DH |
627 | error: |
628 | abort_creds(new); | |
629 | return retval; | |
1da177e4 LT |
630 | } |
631 | ||
a29c33f4 | 632 | SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp) |
1da177e4 | 633 | { |
86a264ab | 634 | const struct cred *cred = current_cred(); |
1da177e4 | 635 | int retval; |
a29c33f4 EB |
636 | uid_t ruid, euid, suid; |
637 | ||
638 | ruid = from_kuid_munged(cred->user_ns, cred->uid); | |
639 | euid = from_kuid_munged(cred->user_ns, cred->euid); | |
640 | suid = from_kuid_munged(cred->user_ns, cred->suid); | |
1da177e4 | 641 | |
ec94fc3d | 642 | retval = put_user(ruid, ruidp); |
643 | if (!retval) { | |
644 | retval = put_user(euid, euidp); | |
645 | if (!retval) | |
646 | return put_user(suid, suidp); | |
647 | } | |
1da177e4 LT |
648 | return retval; |
649 | } | |
650 | ||
651 | /* | |
652 | * Same as above, but for rgid, egid, sgid. | |
653 | */ | |
ae1251ab | 654 | SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) |
1da177e4 | 655 | { |
a29c33f4 | 656 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
657 | const struct cred *old; |
658 | struct cred *new; | |
1da177e4 | 659 | int retval; |
a29c33f4 EB |
660 | kgid_t krgid, kegid, ksgid; |
661 | ||
662 | krgid = make_kgid(ns, rgid); | |
663 | kegid = make_kgid(ns, egid); | |
664 | ksgid = make_kgid(ns, sgid); | |
665 | ||
666 | if ((rgid != (gid_t) -1) && !gid_valid(krgid)) | |
667 | return -EINVAL; | |
668 | if ((egid != (gid_t) -1) && !gid_valid(kegid)) | |
669 | return -EINVAL; | |
670 | if ((sgid != (gid_t) -1) && !gid_valid(ksgid)) | |
671 | return -EINVAL; | |
1da177e4 | 672 | |
d84f4f99 DH |
673 | new = prepare_creds(); |
674 | if (!new) | |
675 | return -ENOMEM; | |
676 | old = current_cred(); | |
677 | ||
d84f4f99 | 678 | retval = -EPERM; |
c7b96acf | 679 | if (!ns_capable(old->user_ns, CAP_SETGID)) { |
a29c33f4 EB |
680 | if (rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) && |
681 | !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid)) | |
d84f4f99 | 682 | goto error; |
a29c33f4 EB |
683 | if (egid != (gid_t) -1 && !gid_eq(kegid, old->gid) && |
684 | !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid)) | |
d84f4f99 | 685 | goto error; |
a29c33f4 EB |
686 | if (sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) && |
687 | !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid)) | |
d84f4f99 | 688 | goto error; |
1da177e4 | 689 | } |
d84f4f99 | 690 | |
1da177e4 | 691 | if (rgid != (gid_t) -1) |
a29c33f4 | 692 | new->gid = krgid; |
d84f4f99 | 693 | if (egid != (gid_t) -1) |
a29c33f4 | 694 | new->egid = kegid; |
1da177e4 | 695 | if (sgid != (gid_t) -1) |
a29c33f4 | 696 | new->sgid = ksgid; |
d84f4f99 | 697 | new->fsgid = new->egid; |
1da177e4 | 698 | |
d84f4f99 DH |
699 | return commit_creds(new); |
700 | ||
701 | error: | |
702 | abort_creds(new); | |
703 | return retval; | |
1da177e4 LT |
704 | } |
705 | ||
a29c33f4 | 706 | SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp) |
1da177e4 | 707 | { |
86a264ab | 708 | const struct cred *cred = current_cred(); |
1da177e4 | 709 | int retval; |
a29c33f4 EB |
710 | gid_t rgid, egid, sgid; |
711 | ||
712 | rgid = from_kgid_munged(cred->user_ns, cred->gid); | |
713 | egid = from_kgid_munged(cred->user_ns, cred->egid); | |
714 | sgid = from_kgid_munged(cred->user_ns, cred->sgid); | |
1da177e4 | 715 | |
ec94fc3d | 716 | retval = put_user(rgid, rgidp); |
717 | if (!retval) { | |
718 | retval = put_user(egid, egidp); | |
719 | if (!retval) | |
720 | retval = put_user(sgid, sgidp); | |
721 | } | |
1da177e4 LT |
722 | |
723 | return retval; | |
724 | } | |
725 | ||
726 | ||
727 | /* | |
728 | * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This | |
729 | * is used for "access()" and for the NFS daemon (letting nfsd stay at | |
730 | * whatever uid it wants to). It normally shadows "euid", except when | |
731 | * explicitly set by setfsuid() or for access.. | |
732 | */ | |
ae1251ab | 733 | SYSCALL_DEFINE1(setfsuid, uid_t, uid) |
1da177e4 | 734 | { |
d84f4f99 DH |
735 | const struct cred *old; |
736 | struct cred *new; | |
737 | uid_t old_fsuid; | |
a29c33f4 EB |
738 | kuid_t kuid; |
739 | ||
740 | old = current_cred(); | |
741 | old_fsuid = from_kuid_munged(old->user_ns, old->fsuid); | |
742 | ||
743 | kuid = make_kuid(old->user_ns, uid); | |
744 | if (!uid_valid(kuid)) | |
745 | return old_fsuid; | |
1da177e4 | 746 | |
d84f4f99 DH |
747 | new = prepare_creds(); |
748 | if (!new) | |
a29c33f4 | 749 | return old_fsuid; |
1da177e4 | 750 | |
a29c33f4 EB |
751 | if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) || |
752 | uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) || | |
c7b96acf | 753 | ns_capable(old->user_ns, CAP_SETUID)) { |
a29c33f4 EB |
754 | if (!uid_eq(kuid, old->fsuid)) { |
755 | new->fsuid = kuid; | |
d84f4f99 DH |
756 | if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) |
757 | goto change_okay; | |
1da177e4 | 758 | } |
1da177e4 LT |
759 | } |
760 | ||
d84f4f99 DH |
761 | abort_creds(new); |
762 | return old_fsuid; | |
1da177e4 | 763 | |
d84f4f99 DH |
764 | change_okay: |
765 | commit_creds(new); | |
1da177e4 LT |
766 | return old_fsuid; |
767 | } | |
768 | ||
769 | /* | |
f42df9e6 | 770 | * Samma på svenska.. |
1da177e4 | 771 | */ |
ae1251ab | 772 | SYSCALL_DEFINE1(setfsgid, gid_t, gid) |
1da177e4 | 773 | { |
d84f4f99 DH |
774 | const struct cred *old; |
775 | struct cred *new; | |
776 | gid_t old_fsgid; | |
a29c33f4 EB |
777 | kgid_t kgid; |
778 | ||
779 | old = current_cred(); | |
780 | old_fsgid = from_kgid_munged(old->user_ns, old->fsgid); | |
781 | ||
782 | kgid = make_kgid(old->user_ns, gid); | |
783 | if (!gid_valid(kgid)) | |
784 | return old_fsgid; | |
d84f4f99 DH |
785 | |
786 | new = prepare_creds(); | |
787 | if (!new) | |
a29c33f4 | 788 | return old_fsgid; |
1da177e4 | 789 | |
a29c33f4 EB |
790 | if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) || |
791 | gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) || | |
c7b96acf | 792 | ns_capable(old->user_ns, CAP_SETGID)) { |
a29c33f4 EB |
793 | if (!gid_eq(kgid, old->fsgid)) { |
794 | new->fsgid = kgid; | |
d84f4f99 | 795 | goto change_okay; |
1da177e4 | 796 | } |
1da177e4 | 797 | } |
d84f4f99 | 798 | |
d84f4f99 DH |
799 | abort_creds(new); |
800 | return old_fsgid; | |
801 | ||
802 | change_okay: | |
803 | commit_creds(new); | |
1da177e4 LT |
804 | return old_fsgid; |
805 | } | |
806 | ||
4a22f166 SR |
807 | /** |
808 | * sys_getpid - return the thread group id of the current process | |
809 | * | |
810 | * Note, despite the name, this returns the tgid not the pid. The tgid and | |
811 | * the pid are identical unless CLONE_THREAD was specified on clone() in | |
812 | * which case the tgid is the same in all threads of the same group. | |
813 | * | |
814 | * This is SMP safe as current->tgid does not change. | |
815 | */ | |
816 | SYSCALL_DEFINE0(getpid) | |
817 | { | |
818 | return task_tgid_vnr(current); | |
819 | } | |
820 | ||
821 | /* Thread ID - the internal kernel "pid" */ | |
822 | SYSCALL_DEFINE0(gettid) | |
823 | { | |
824 | return task_pid_vnr(current); | |
825 | } | |
826 | ||
827 | /* | |
828 | * Accessing ->real_parent is not SMP-safe, it could | |
829 | * change from under us. However, we can use a stale | |
830 | * value of ->real_parent under rcu_read_lock(), see | |
831 | * release_task()->call_rcu(delayed_put_task_struct). | |
832 | */ | |
833 | SYSCALL_DEFINE0(getppid) | |
834 | { | |
835 | int pid; | |
836 | ||
837 | rcu_read_lock(); | |
838 | pid = task_tgid_vnr(rcu_dereference(current->real_parent)); | |
839 | rcu_read_unlock(); | |
840 | ||
841 | return pid; | |
842 | } | |
843 | ||
844 | SYSCALL_DEFINE0(getuid) | |
845 | { | |
846 | /* Only we change this so SMP safe */ | |
847 | return from_kuid_munged(current_user_ns(), current_uid()); | |
848 | } | |
849 | ||
850 | SYSCALL_DEFINE0(geteuid) | |
851 | { | |
852 | /* Only we change this so SMP safe */ | |
853 | return from_kuid_munged(current_user_ns(), current_euid()); | |
854 | } | |
855 | ||
856 | SYSCALL_DEFINE0(getgid) | |
857 | { | |
858 | /* Only we change this so SMP safe */ | |
859 | return from_kgid_munged(current_user_ns(), current_gid()); | |
860 | } | |
861 | ||
862 | SYSCALL_DEFINE0(getegid) | |
863 | { | |
864 | /* Only we change this so SMP safe */ | |
865 | return from_kgid_munged(current_user_ns(), current_egid()); | |
866 | } | |
867 | ||
f06febc9 FM |
868 | void do_sys_times(struct tms *tms) |
869 | { | |
0cf55e1e | 870 | cputime_t tgutime, tgstime, cutime, cstime; |
f06febc9 | 871 | |
e80d0a1a | 872 | thread_group_cputime_adjusted(current, &tgutime, &tgstime); |
f06febc9 FM |
873 | cutime = current->signal->cutime; |
874 | cstime = current->signal->cstime; | |
0cf55e1e HS |
875 | tms->tms_utime = cputime_to_clock_t(tgutime); |
876 | tms->tms_stime = cputime_to_clock_t(tgstime); | |
f06febc9 FM |
877 | tms->tms_cutime = cputime_to_clock_t(cutime); |
878 | tms->tms_cstime = cputime_to_clock_t(cstime); | |
879 | } | |
880 | ||
58fd3aa2 | 881 | SYSCALL_DEFINE1(times, struct tms __user *, tbuf) |
1da177e4 | 882 | { |
1da177e4 LT |
883 | if (tbuf) { |
884 | struct tms tmp; | |
f06febc9 FM |
885 | |
886 | do_sys_times(&tmp); | |
1da177e4 LT |
887 | if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
888 | return -EFAULT; | |
889 | } | |
e3d5a27d | 890 | force_successful_syscall_return(); |
1da177e4 LT |
891 | return (long) jiffies_64_to_clock_t(get_jiffies_64()); |
892 | } | |
893 | ||
894 | /* | |
895 | * This needs some heavy checking ... | |
896 | * I just haven't the stomach for it. I also don't fully | |
897 | * understand sessions/pgrp etc. Let somebody who does explain it. | |
898 | * | |
899 | * OK, I think I have the protection semantics right.... this is really | |
900 | * only important on a multi-user system anyway, to make sure one user | |
901 | * can't send a signal to a process owned by another. -TYT, 12/12/91 | |
902 | * | |
98611e4e | 903 | * !PF_FORKNOEXEC check to conform completely to POSIX. |
1da177e4 | 904 | */ |
b290ebe2 | 905 | SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) |
1da177e4 LT |
906 | { |
907 | struct task_struct *p; | |
ee0acf90 | 908 | struct task_struct *group_leader = current->group_leader; |
4e021306 ON |
909 | struct pid *pgrp; |
910 | int err; | |
1da177e4 LT |
911 | |
912 | if (!pid) | |
b488893a | 913 | pid = task_pid_vnr(group_leader); |
1da177e4 LT |
914 | if (!pgid) |
915 | pgid = pid; | |
916 | if (pgid < 0) | |
917 | return -EINVAL; | |
950eaaca | 918 | rcu_read_lock(); |
1da177e4 LT |
919 | |
920 | /* From this point forward we keep holding onto the tasklist lock | |
921 | * so that our parent does not change from under us. -DaveM | |
922 | */ | |
923 | write_lock_irq(&tasklist_lock); | |
924 | ||
925 | err = -ESRCH; | |
4e021306 | 926 | p = find_task_by_vpid(pid); |
1da177e4 LT |
927 | if (!p) |
928 | goto out; | |
929 | ||
930 | err = -EINVAL; | |
931 | if (!thread_group_leader(p)) | |
932 | goto out; | |
933 | ||
4e021306 | 934 | if (same_thread_group(p->real_parent, group_leader)) { |
1da177e4 | 935 | err = -EPERM; |
41487c65 | 936 | if (task_session(p) != task_session(group_leader)) |
1da177e4 LT |
937 | goto out; |
938 | err = -EACCES; | |
98611e4e | 939 | if (!(p->flags & PF_FORKNOEXEC)) |
1da177e4 LT |
940 | goto out; |
941 | } else { | |
942 | err = -ESRCH; | |
ee0acf90 | 943 | if (p != group_leader) |
1da177e4 LT |
944 | goto out; |
945 | } | |
946 | ||
947 | err = -EPERM; | |
948 | if (p->signal->leader) | |
949 | goto out; | |
950 | ||
4e021306 | 951 | pgrp = task_pid(p); |
1da177e4 | 952 | if (pgid != pid) { |
b488893a | 953 | struct task_struct *g; |
1da177e4 | 954 | |
4e021306 ON |
955 | pgrp = find_vpid(pgid); |
956 | g = pid_task(pgrp, PIDTYPE_PGID); | |
41487c65 | 957 | if (!g || task_session(g) != task_session(group_leader)) |
f020bc46 | 958 | goto out; |
1da177e4 LT |
959 | } |
960 | ||
1da177e4 LT |
961 | err = security_task_setpgid(p, pgid); |
962 | if (err) | |
963 | goto out; | |
964 | ||
1b0f7ffd | 965 | if (task_pgrp(p) != pgrp) |
83beaf3c | 966 | change_pid(p, PIDTYPE_PGID, pgrp); |
1da177e4 LT |
967 | |
968 | err = 0; | |
969 | out: | |
970 | /* All paths lead to here, thus we are safe. -DaveM */ | |
971 | write_unlock_irq(&tasklist_lock); | |
950eaaca | 972 | rcu_read_unlock(); |
1da177e4 LT |
973 | return err; |
974 | } | |
975 | ||
dbf040d9 | 976 | SYSCALL_DEFINE1(getpgid, pid_t, pid) |
1da177e4 | 977 | { |
12a3de0a ON |
978 | struct task_struct *p; |
979 | struct pid *grp; | |
980 | int retval; | |
981 | ||
982 | rcu_read_lock(); | |
756184b7 | 983 | if (!pid) |
12a3de0a | 984 | grp = task_pgrp(current); |
756184b7 | 985 | else { |
1da177e4 | 986 | retval = -ESRCH; |
12a3de0a ON |
987 | p = find_task_by_vpid(pid); |
988 | if (!p) | |
989 | goto out; | |
990 | grp = task_pgrp(p); | |
991 | if (!grp) | |
992 | goto out; | |
993 | ||
994 | retval = security_task_getpgid(p); | |
995 | if (retval) | |
996 | goto out; | |
1da177e4 | 997 | } |
12a3de0a ON |
998 | retval = pid_vnr(grp); |
999 | out: | |
1000 | rcu_read_unlock(); | |
1001 | return retval; | |
1da177e4 LT |
1002 | } |
1003 | ||
1004 | #ifdef __ARCH_WANT_SYS_GETPGRP | |
1005 | ||
dbf040d9 | 1006 | SYSCALL_DEFINE0(getpgrp) |
1da177e4 | 1007 | { |
12a3de0a | 1008 | return sys_getpgid(0); |
1da177e4 LT |
1009 | } |
1010 | ||
1011 | #endif | |
1012 | ||
dbf040d9 | 1013 | SYSCALL_DEFINE1(getsid, pid_t, pid) |
1da177e4 | 1014 | { |
1dd768c0 ON |
1015 | struct task_struct *p; |
1016 | struct pid *sid; | |
1017 | int retval; | |
1018 | ||
1019 | rcu_read_lock(); | |
756184b7 | 1020 | if (!pid) |
1dd768c0 | 1021 | sid = task_session(current); |
756184b7 | 1022 | else { |
1da177e4 | 1023 | retval = -ESRCH; |
1dd768c0 ON |
1024 | p = find_task_by_vpid(pid); |
1025 | if (!p) | |
1026 | goto out; | |
1027 | sid = task_session(p); | |
1028 | if (!sid) | |
1029 | goto out; | |
1030 | ||
1031 | retval = security_task_getsid(p); | |
1032 | if (retval) | |
1033 | goto out; | |
1da177e4 | 1034 | } |
1dd768c0 ON |
1035 | retval = pid_vnr(sid); |
1036 | out: | |
1037 | rcu_read_unlock(); | |
1038 | return retval; | |
1da177e4 LT |
1039 | } |
1040 | ||
81dabb46 ON |
1041 | static void set_special_pids(struct pid *pid) |
1042 | { | |
1043 | struct task_struct *curr = current->group_leader; | |
1044 | ||
1045 | if (task_session(curr) != pid) | |
1046 | change_pid(curr, PIDTYPE_SID, pid); | |
1047 | ||
1048 | if (task_pgrp(curr) != pid) | |
1049 | change_pid(curr, PIDTYPE_PGID, pid); | |
1050 | } | |
1051 | ||
b290ebe2 | 1052 | SYSCALL_DEFINE0(setsid) |
1da177e4 | 1053 | { |
e19f247a | 1054 | struct task_struct *group_leader = current->group_leader; |
e4cc0a9c ON |
1055 | struct pid *sid = task_pid(group_leader); |
1056 | pid_t session = pid_vnr(sid); | |
1da177e4 LT |
1057 | int err = -EPERM; |
1058 | ||
1da177e4 | 1059 | write_lock_irq(&tasklist_lock); |
390e2ff0 EB |
1060 | /* Fail if I am already a session leader */ |
1061 | if (group_leader->signal->leader) | |
1062 | goto out; | |
1063 | ||
430c6231 ON |
1064 | /* Fail if a process group id already exists that equals the |
1065 | * proposed session id. | |
390e2ff0 | 1066 | */ |
6806aac6 | 1067 | if (pid_task(sid, PIDTYPE_PGID)) |
1da177e4 LT |
1068 | goto out; |
1069 | ||
e19f247a | 1070 | group_leader->signal->leader = 1; |
81dabb46 | 1071 | set_special_pids(sid); |
24ec839c | 1072 | |
9c9f4ded | 1073 | proc_clear_tty(group_leader); |
24ec839c | 1074 | |
e4cc0a9c | 1075 | err = session; |
1da177e4 LT |
1076 | out: |
1077 | write_unlock_irq(&tasklist_lock); | |
5091faa4 | 1078 | if (err > 0) { |
0d0df599 | 1079 | proc_sid_connector(group_leader); |
5091faa4 MG |
1080 | sched_autogroup_create_attach(group_leader); |
1081 | } | |
1da177e4 LT |
1082 | return err; |
1083 | } | |
1084 | ||
1da177e4 LT |
1085 | DECLARE_RWSEM(uts_sem); |
1086 | ||
e28cbf22 CH |
1087 | #ifdef COMPAT_UTS_MACHINE |
1088 | #define override_architecture(name) \ | |
46da2766 | 1089 | (personality(current->personality) == PER_LINUX32 && \ |
e28cbf22 CH |
1090 | copy_to_user(name->machine, COMPAT_UTS_MACHINE, \ |
1091 | sizeof(COMPAT_UTS_MACHINE))) | |
1092 | #else | |
1093 | #define override_architecture(name) 0 | |
1094 | #endif | |
1095 | ||
be27425d AK |
1096 | /* |
1097 | * Work around broken programs that cannot handle "Linux 3.0". | |
1098 | * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40 | |
1099 | */ | |
2702b152 | 1100 | static int override_release(char __user *release, size_t len) |
be27425d AK |
1101 | { |
1102 | int ret = 0; | |
be27425d AK |
1103 | |
1104 | if (current->personality & UNAME26) { | |
2702b152 KC |
1105 | const char *rest = UTS_RELEASE; |
1106 | char buf[65] = { 0 }; | |
be27425d AK |
1107 | int ndots = 0; |
1108 | unsigned v; | |
2702b152 | 1109 | size_t copy; |
be27425d AK |
1110 | |
1111 | while (*rest) { | |
1112 | if (*rest == '.' && ++ndots >= 3) | |
1113 | break; | |
1114 | if (!isdigit(*rest) && *rest != '.') | |
1115 | break; | |
1116 | rest++; | |
1117 | } | |
1118 | v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 40; | |
31fd84b9 | 1119 | copy = clamp_t(size_t, len, 1, sizeof(buf)); |
2702b152 KC |
1120 | copy = scnprintf(buf, copy, "2.6.%u%s", v, rest); |
1121 | ret = copy_to_user(release, buf, copy + 1); | |
be27425d AK |
1122 | } |
1123 | return ret; | |
1124 | } | |
1125 | ||
e48fbb69 | 1126 | SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name) |
1da177e4 LT |
1127 | { |
1128 | int errno = 0; | |
1129 | ||
1130 | down_read(&uts_sem); | |
e9ff3990 | 1131 | if (copy_to_user(name, utsname(), sizeof *name)) |
1da177e4 LT |
1132 | errno = -EFAULT; |
1133 | up_read(&uts_sem); | |
e28cbf22 | 1134 | |
be27425d AK |
1135 | if (!errno && override_release(name->release, sizeof(name->release))) |
1136 | errno = -EFAULT; | |
e28cbf22 CH |
1137 | if (!errno && override_architecture(name)) |
1138 | errno = -EFAULT; | |
1da177e4 LT |
1139 | return errno; |
1140 | } | |
1141 | ||
5cacdb4a CH |
1142 | #ifdef __ARCH_WANT_SYS_OLD_UNAME |
1143 | /* | |
1144 | * Old cruft | |
1145 | */ | |
1146 | SYSCALL_DEFINE1(uname, struct old_utsname __user *, name) | |
1147 | { | |
1148 | int error = 0; | |
1149 | ||
1150 | if (!name) | |
1151 | return -EFAULT; | |
1152 | ||
1153 | down_read(&uts_sem); | |
1154 | if (copy_to_user(name, utsname(), sizeof(*name))) | |
1155 | error = -EFAULT; | |
1156 | up_read(&uts_sem); | |
1157 | ||
be27425d AK |
1158 | if (!error && override_release(name->release, sizeof(name->release))) |
1159 | error = -EFAULT; | |
5cacdb4a CH |
1160 | if (!error && override_architecture(name)) |
1161 | error = -EFAULT; | |
1162 | return error; | |
1163 | } | |
1164 | ||
1165 | SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name) | |
1166 | { | |
1167 | int error; | |
1168 | ||
1169 | if (!name) | |
1170 | return -EFAULT; | |
1171 | if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname))) | |
1172 | return -EFAULT; | |
1173 | ||
1174 | down_read(&uts_sem); | |
1175 | error = __copy_to_user(&name->sysname, &utsname()->sysname, | |
1176 | __OLD_UTS_LEN); | |
1177 | error |= __put_user(0, name->sysname + __OLD_UTS_LEN); | |
1178 | error |= __copy_to_user(&name->nodename, &utsname()->nodename, | |
1179 | __OLD_UTS_LEN); | |
1180 | error |= __put_user(0, name->nodename + __OLD_UTS_LEN); | |
1181 | error |= __copy_to_user(&name->release, &utsname()->release, | |
1182 | __OLD_UTS_LEN); | |
1183 | error |= __put_user(0, name->release + __OLD_UTS_LEN); | |
1184 | error |= __copy_to_user(&name->version, &utsname()->version, | |
1185 | __OLD_UTS_LEN); | |
1186 | error |= __put_user(0, name->version + __OLD_UTS_LEN); | |
1187 | error |= __copy_to_user(&name->machine, &utsname()->machine, | |
1188 | __OLD_UTS_LEN); | |
1189 | error |= __put_user(0, name->machine + __OLD_UTS_LEN); | |
1190 | up_read(&uts_sem); | |
1191 | ||
1192 | if (!error && override_architecture(name)) | |
1193 | error = -EFAULT; | |
be27425d AK |
1194 | if (!error && override_release(name->release, sizeof(name->release))) |
1195 | error = -EFAULT; | |
5cacdb4a CH |
1196 | return error ? -EFAULT : 0; |
1197 | } | |
1198 | #endif | |
1199 | ||
5a8a82b1 | 1200 | SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) |
1da177e4 LT |
1201 | { |
1202 | int errno; | |
1203 | char tmp[__NEW_UTS_LEN]; | |
1204 | ||
bb96a6f5 | 1205 | if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
1da177e4 | 1206 | return -EPERM; |
fc832ad3 | 1207 | |
1da177e4 LT |
1208 | if (len < 0 || len > __NEW_UTS_LEN) |
1209 | return -EINVAL; | |
1210 | down_write(&uts_sem); | |
1211 | errno = -EFAULT; | |
1212 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1213 | struct new_utsname *u = utsname(); |
1214 | ||
1215 | memcpy(u->nodename, tmp, len); | |
1216 | memset(u->nodename + len, 0, sizeof(u->nodename) - len); | |
1da177e4 | 1217 | errno = 0; |
499eea6b | 1218 | uts_proc_notify(UTS_PROC_HOSTNAME); |
1da177e4 LT |
1219 | } |
1220 | up_write(&uts_sem); | |
1221 | return errno; | |
1222 | } | |
1223 | ||
1224 | #ifdef __ARCH_WANT_SYS_GETHOSTNAME | |
1225 | ||
5a8a82b1 | 1226 | SYSCALL_DEFINE2(gethostname, char __user *, name, int, len) |
1da177e4 LT |
1227 | { |
1228 | int i, errno; | |
9679e4dd | 1229 | struct new_utsname *u; |
1da177e4 LT |
1230 | |
1231 | if (len < 0) | |
1232 | return -EINVAL; | |
1233 | down_read(&uts_sem); | |
9679e4dd AM |
1234 | u = utsname(); |
1235 | i = 1 + strlen(u->nodename); | |
1da177e4 LT |
1236 | if (i > len) |
1237 | i = len; | |
1238 | errno = 0; | |
9679e4dd | 1239 | if (copy_to_user(name, u->nodename, i)) |
1da177e4 LT |
1240 | errno = -EFAULT; |
1241 | up_read(&uts_sem); | |
1242 | return errno; | |
1243 | } | |
1244 | ||
1245 | #endif | |
1246 | ||
1247 | /* | |
1248 | * Only setdomainname; getdomainname can be implemented by calling | |
1249 | * uname() | |
1250 | */ | |
5a8a82b1 | 1251 | SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) |
1da177e4 LT |
1252 | { |
1253 | int errno; | |
1254 | char tmp[__NEW_UTS_LEN]; | |
1255 | ||
fc832ad3 | 1256 | if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
1da177e4 LT |
1257 | return -EPERM; |
1258 | if (len < 0 || len > __NEW_UTS_LEN) | |
1259 | return -EINVAL; | |
1260 | ||
1261 | down_write(&uts_sem); | |
1262 | errno = -EFAULT; | |
1263 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1264 | struct new_utsname *u = utsname(); |
1265 | ||
1266 | memcpy(u->domainname, tmp, len); | |
1267 | memset(u->domainname + len, 0, sizeof(u->domainname) - len); | |
1da177e4 | 1268 | errno = 0; |
499eea6b | 1269 | uts_proc_notify(UTS_PROC_DOMAINNAME); |
1da177e4 LT |
1270 | } |
1271 | up_write(&uts_sem); | |
1272 | return errno; | |
1273 | } | |
1274 | ||
e48fbb69 | 1275 | SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1da177e4 | 1276 | { |
b9518345 JS |
1277 | struct rlimit value; |
1278 | int ret; | |
1279 | ||
1280 | ret = do_prlimit(current, resource, NULL, &value); | |
1281 | if (!ret) | |
1282 | ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; | |
1283 | ||
1284 | return ret; | |
1da177e4 LT |
1285 | } |
1286 | ||
1287 | #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT | |
1288 | ||
1289 | /* | |
1290 | * Back compatibility for getrlimit. Needed for some apps. | |
1291 | */ | |
e48fbb69 HC |
1292 | SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, |
1293 | struct rlimit __user *, rlim) | |
1da177e4 LT |
1294 | { |
1295 | struct rlimit x; | |
1296 | if (resource >= RLIM_NLIMITS) | |
1297 | return -EINVAL; | |
1298 | ||
1299 | task_lock(current->group_leader); | |
1300 | x = current->signal->rlim[resource]; | |
1301 | task_unlock(current->group_leader); | |
756184b7 | 1302 | if (x.rlim_cur > 0x7FFFFFFF) |
1da177e4 | 1303 | x.rlim_cur = 0x7FFFFFFF; |
756184b7 | 1304 | if (x.rlim_max > 0x7FFFFFFF) |
1da177e4 | 1305 | x.rlim_max = 0x7FFFFFFF; |
ec94fc3d | 1306 | return copy_to_user(rlim, &x, sizeof(x)) ? -EFAULT : 0; |
1da177e4 LT |
1307 | } |
1308 | ||
1309 | #endif | |
1310 | ||
c022a0ac JS |
1311 | static inline bool rlim64_is_infinity(__u64 rlim64) |
1312 | { | |
1313 | #if BITS_PER_LONG < 64 | |
1314 | return rlim64 >= ULONG_MAX; | |
1315 | #else | |
1316 | return rlim64 == RLIM64_INFINITY; | |
1317 | #endif | |
1318 | } | |
1319 | ||
1320 | static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64) | |
1321 | { | |
1322 | if (rlim->rlim_cur == RLIM_INFINITY) | |
1323 | rlim64->rlim_cur = RLIM64_INFINITY; | |
1324 | else | |
1325 | rlim64->rlim_cur = rlim->rlim_cur; | |
1326 | if (rlim->rlim_max == RLIM_INFINITY) | |
1327 | rlim64->rlim_max = RLIM64_INFINITY; | |
1328 | else | |
1329 | rlim64->rlim_max = rlim->rlim_max; | |
1330 | } | |
1331 | ||
1332 | static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim) | |
1333 | { | |
1334 | if (rlim64_is_infinity(rlim64->rlim_cur)) | |
1335 | rlim->rlim_cur = RLIM_INFINITY; | |
1336 | else | |
1337 | rlim->rlim_cur = (unsigned long)rlim64->rlim_cur; | |
1338 | if (rlim64_is_infinity(rlim64->rlim_max)) | |
1339 | rlim->rlim_max = RLIM_INFINITY; | |
1340 | else | |
1341 | rlim->rlim_max = (unsigned long)rlim64->rlim_max; | |
1342 | } | |
1343 | ||
1c1e618d | 1344 | /* make sure you are allowed to change @tsk limits before calling this */ |
5b41535a JS |
1345 | int do_prlimit(struct task_struct *tsk, unsigned int resource, |
1346 | struct rlimit *new_rlim, struct rlimit *old_rlim) | |
1da177e4 | 1347 | { |
5b41535a | 1348 | struct rlimit *rlim; |
86f162f4 | 1349 | int retval = 0; |
1da177e4 LT |
1350 | |
1351 | if (resource >= RLIM_NLIMITS) | |
1352 | return -EINVAL; | |
5b41535a JS |
1353 | if (new_rlim) { |
1354 | if (new_rlim->rlim_cur > new_rlim->rlim_max) | |
1355 | return -EINVAL; | |
1356 | if (resource == RLIMIT_NOFILE && | |
1357 | new_rlim->rlim_max > sysctl_nr_open) | |
1358 | return -EPERM; | |
1359 | } | |
1da177e4 | 1360 | |
1c1e618d JS |
1361 | /* protect tsk->signal and tsk->sighand from disappearing */ |
1362 | read_lock(&tasklist_lock); | |
1363 | if (!tsk->sighand) { | |
1364 | retval = -ESRCH; | |
1365 | goto out; | |
1366 | } | |
1367 | ||
5b41535a | 1368 | rlim = tsk->signal->rlim + resource; |
86f162f4 | 1369 | task_lock(tsk->group_leader); |
5b41535a | 1370 | if (new_rlim) { |
fc832ad3 SH |
1371 | /* Keep the capable check against init_user_ns until |
1372 | cgroups can contain all limits */ | |
5b41535a JS |
1373 | if (new_rlim->rlim_max > rlim->rlim_max && |
1374 | !capable(CAP_SYS_RESOURCE)) | |
1375 | retval = -EPERM; | |
1376 | if (!retval) | |
1377 | retval = security_task_setrlimit(tsk->group_leader, | |
1378 | resource, new_rlim); | |
1379 | if (resource == RLIMIT_CPU && new_rlim->rlim_cur == 0) { | |
1380 | /* | |
1381 | * The caller is asking for an immediate RLIMIT_CPU | |
1382 | * expiry. But we use the zero value to mean "it was | |
1383 | * never set". So let's cheat and make it one second | |
1384 | * instead | |
1385 | */ | |
1386 | new_rlim->rlim_cur = 1; | |
1387 | } | |
1388 | } | |
1389 | if (!retval) { | |
1390 | if (old_rlim) | |
1391 | *old_rlim = *rlim; | |
1392 | if (new_rlim) | |
1393 | *rlim = *new_rlim; | |
9926e4c7 | 1394 | } |
7855c35d | 1395 | task_unlock(tsk->group_leader); |
1da177e4 | 1396 | |
d3561f78 AM |
1397 | /* |
1398 | * RLIMIT_CPU handling. Note that the kernel fails to return an error | |
1399 | * code if it rejected the user's attempt to set RLIMIT_CPU. This is a | |
1400 | * very long-standing error, and fixing it now risks breakage of | |
1401 | * applications, so we live with it | |
1402 | */ | |
5b41535a JS |
1403 | if (!retval && new_rlim && resource == RLIMIT_CPU && |
1404 | new_rlim->rlim_cur != RLIM_INFINITY) | |
1405 | update_rlimit_cpu(tsk, new_rlim->rlim_cur); | |
ec9e16ba | 1406 | out: |
1c1e618d | 1407 | read_unlock(&tasklist_lock); |
2fb9d268 | 1408 | return retval; |
1da177e4 LT |
1409 | } |
1410 | ||
c022a0ac JS |
1411 | /* rcu lock must be held */ |
1412 | static int check_prlimit_permission(struct task_struct *task) | |
1413 | { | |
1414 | const struct cred *cred = current_cred(), *tcred; | |
1415 | ||
fc832ad3 SH |
1416 | if (current == task) |
1417 | return 0; | |
c022a0ac | 1418 | |
fc832ad3 | 1419 | tcred = __task_cred(task); |
5af66203 EB |
1420 | if (uid_eq(cred->uid, tcred->euid) && |
1421 | uid_eq(cred->uid, tcred->suid) && | |
1422 | uid_eq(cred->uid, tcred->uid) && | |
1423 | gid_eq(cred->gid, tcred->egid) && | |
1424 | gid_eq(cred->gid, tcred->sgid) && | |
1425 | gid_eq(cred->gid, tcred->gid)) | |
fc832ad3 | 1426 | return 0; |
c4a4d603 | 1427 | if (ns_capable(tcred->user_ns, CAP_SYS_RESOURCE)) |
fc832ad3 SH |
1428 | return 0; |
1429 | ||
1430 | return -EPERM; | |
c022a0ac JS |
1431 | } |
1432 | ||
1433 | SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource, | |
1434 | const struct rlimit64 __user *, new_rlim, | |
1435 | struct rlimit64 __user *, old_rlim) | |
1436 | { | |
1437 | struct rlimit64 old64, new64; | |
1438 | struct rlimit old, new; | |
1439 | struct task_struct *tsk; | |
1440 | int ret; | |
1441 | ||
1442 | if (new_rlim) { | |
1443 | if (copy_from_user(&new64, new_rlim, sizeof(new64))) | |
1444 | return -EFAULT; | |
1445 | rlim64_to_rlim(&new64, &new); | |
1446 | } | |
1447 | ||
1448 | rcu_read_lock(); | |
1449 | tsk = pid ? find_task_by_vpid(pid) : current; | |
1450 | if (!tsk) { | |
1451 | rcu_read_unlock(); | |
1452 | return -ESRCH; | |
1453 | } | |
1454 | ret = check_prlimit_permission(tsk); | |
1455 | if (ret) { | |
1456 | rcu_read_unlock(); | |
1457 | return ret; | |
1458 | } | |
1459 | get_task_struct(tsk); | |
1460 | rcu_read_unlock(); | |
1461 | ||
1462 | ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL, | |
1463 | old_rlim ? &old : NULL); | |
1464 | ||
1465 | if (!ret && old_rlim) { | |
1466 | rlim_to_rlim64(&old, &old64); | |
1467 | if (copy_to_user(old_rlim, &old64, sizeof(old64))) | |
1468 | ret = -EFAULT; | |
1469 | } | |
1470 | ||
1471 | put_task_struct(tsk); | |
1472 | return ret; | |
1473 | } | |
1474 | ||
7855c35d JS |
1475 | SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1476 | { | |
1477 | struct rlimit new_rlim; | |
1478 | ||
1479 | if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) | |
1480 | return -EFAULT; | |
5b41535a | 1481 | return do_prlimit(current, resource, &new_rlim, NULL); |
7855c35d JS |
1482 | } |
1483 | ||
1da177e4 LT |
1484 | /* |
1485 | * It would make sense to put struct rusage in the task_struct, | |
1486 | * except that would make the task_struct be *really big*. After | |
1487 | * task_struct gets moved into malloc'ed memory, it would | |
1488 | * make sense to do this. It will make moving the rest of the information | |
1489 | * a lot simpler! (Which we're not doing right now because we're not | |
1490 | * measuring them yet). | |
1491 | * | |
1da177e4 LT |
1492 | * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
1493 | * races with threads incrementing their own counters. But since word | |
1494 | * reads are atomic, we either get new values or old values and we don't | |
1495 | * care which for the sums. We always take the siglock to protect reading | |
1496 | * the c* fields from p->signal from races with exit.c updating those | |
1497 | * fields when reaping, so a sample either gets all the additions of a | |
1498 | * given child after it's reaped, or none so this sample is before reaping. | |
2dd0ebcd | 1499 | * |
de047c1b RT |
1500 | * Locking: |
1501 | * We need to take the siglock for CHILDEREN, SELF and BOTH | |
1502 | * for the cases current multithreaded, non-current single threaded | |
1503 | * non-current multithreaded. Thread traversal is now safe with | |
1504 | * the siglock held. | |
1505 | * Strictly speaking, we donot need to take the siglock if we are current and | |
1506 | * single threaded, as no one else can take our signal_struct away, no one | |
1507 | * else can reap the children to update signal->c* counters, and no one else | |
1508 | * can race with the signal-> fields. If we do not take any lock, the | |
1509 | * signal-> fields could be read out of order while another thread was just | |
1510 | * exiting. So we should place a read memory barrier when we avoid the lock. | |
1511 | * On the writer side, write memory barrier is implied in __exit_signal | |
1512 | * as __exit_signal releases the siglock spinlock after updating the signal-> | |
1513 | * fields. But we don't do this yet to keep things simple. | |
2dd0ebcd | 1514 | * |
1da177e4 LT |
1515 | */ |
1516 | ||
f06febc9 | 1517 | static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) |
679c9cd4 | 1518 | { |
679c9cd4 SK |
1519 | r->ru_nvcsw += t->nvcsw; |
1520 | r->ru_nivcsw += t->nivcsw; | |
1521 | r->ru_minflt += t->min_flt; | |
1522 | r->ru_majflt += t->maj_flt; | |
1523 | r->ru_inblock += task_io_get_inblock(t); | |
1524 | r->ru_oublock += task_io_get_oublock(t); | |
1525 | } | |
1526 | ||
1da177e4 LT |
1527 | static void k_getrusage(struct task_struct *p, int who, struct rusage *r) |
1528 | { | |
1529 | struct task_struct *t; | |
1530 | unsigned long flags; | |
0cf55e1e | 1531 | cputime_t tgutime, tgstime, utime, stime; |
1f10206c | 1532 | unsigned long maxrss = 0; |
1da177e4 | 1533 | |
ec94fc3d | 1534 | memset((char *)r, 0, sizeof (*r)); |
64861634 | 1535 | utime = stime = 0; |
1da177e4 | 1536 | |
679c9cd4 | 1537 | if (who == RUSAGE_THREAD) { |
e80d0a1a | 1538 | task_cputime_adjusted(current, &utime, &stime); |
f06febc9 | 1539 | accumulate_thread_rusage(p, r); |
1f10206c | 1540 | maxrss = p->signal->maxrss; |
679c9cd4 SK |
1541 | goto out; |
1542 | } | |
1543 | ||
d6cf723a | 1544 | if (!lock_task_sighand(p, &flags)) |
de047c1b | 1545 | return; |
0f59cc4a | 1546 | |
1da177e4 | 1547 | switch (who) { |
ec94fc3d | 1548 | case RUSAGE_BOTH: |
1549 | case RUSAGE_CHILDREN: | |
1550 | utime = p->signal->cutime; | |
1551 | stime = p->signal->cstime; | |
1552 | r->ru_nvcsw = p->signal->cnvcsw; | |
1553 | r->ru_nivcsw = p->signal->cnivcsw; | |
1554 | r->ru_minflt = p->signal->cmin_flt; | |
1555 | r->ru_majflt = p->signal->cmaj_flt; | |
1556 | r->ru_inblock = p->signal->cinblock; | |
1557 | r->ru_oublock = p->signal->coublock; | |
1558 | maxrss = p->signal->cmaxrss; | |
1559 | ||
1560 | if (who == RUSAGE_CHILDREN) | |
1da177e4 | 1561 | break; |
0f59cc4a | 1562 | |
ec94fc3d | 1563 | case RUSAGE_SELF: |
1564 | thread_group_cputime_adjusted(p, &tgutime, &tgstime); | |
1565 | utime += tgutime; | |
1566 | stime += tgstime; | |
1567 | r->ru_nvcsw += p->signal->nvcsw; | |
1568 | r->ru_nivcsw += p->signal->nivcsw; | |
1569 | r->ru_minflt += p->signal->min_flt; | |
1570 | r->ru_majflt += p->signal->maj_flt; | |
1571 | r->ru_inblock += p->signal->inblock; | |
1572 | r->ru_oublock += p->signal->oublock; | |
1573 | if (maxrss < p->signal->maxrss) | |
1574 | maxrss = p->signal->maxrss; | |
1575 | t = p; | |
1576 | do { | |
1577 | accumulate_thread_rusage(t, r); | |
1578 | } while_each_thread(p, t); | |
1579 | break; | |
1580 | ||
1581 | default: | |
1582 | BUG(); | |
1da177e4 | 1583 | } |
de047c1b | 1584 | unlock_task_sighand(p, &flags); |
de047c1b | 1585 | |
679c9cd4 | 1586 | out: |
0f59cc4a ON |
1587 | cputime_to_timeval(utime, &r->ru_utime); |
1588 | cputime_to_timeval(stime, &r->ru_stime); | |
1f10206c JP |
1589 | |
1590 | if (who != RUSAGE_CHILDREN) { | |
1591 | struct mm_struct *mm = get_task_mm(p); | |
ec94fc3d | 1592 | |
1f10206c JP |
1593 | if (mm) { |
1594 | setmax_mm_hiwater_rss(&maxrss, mm); | |
1595 | mmput(mm); | |
1596 | } | |
1597 | } | |
1598 | r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */ | |
1da177e4 LT |
1599 | } |
1600 | ||
1601 | int getrusage(struct task_struct *p, int who, struct rusage __user *ru) | |
1602 | { | |
1603 | struct rusage r; | |
ec94fc3d | 1604 | |
1da177e4 | 1605 | k_getrusage(p, who, &r); |
1da177e4 LT |
1606 | return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
1607 | } | |
1608 | ||
e48fbb69 | 1609 | SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) |
1da177e4 | 1610 | { |
679c9cd4 SK |
1611 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
1612 | who != RUSAGE_THREAD) | |
1da177e4 LT |
1613 | return -EINVAL; |
1614 | return getrusage(current, who, ru); | |
1615 | } | |
1616 | ||
8d2d5c4a AV |
1617 | #ifdef CONFIG_COMPAT |
1618 | COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru) | |
1619 | { | |
1620 | struct rusage r; | |
1621 | ||
1622 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && | |
1623 | who != RUSAGE_THREAD) | |
1624 | return -EINVAL; | |
1625 | ||
1626 | k_getrusage(current, who, &r); | |
1627 | return put_compat_rusage(&r, ru); | |
1628 | } | |
1629 | #endif | |
1630 | ||
e48fbb69 | 1631 | SYSCALL_DEFINE1(umask, int, mask) |
1da177e4 LT |
1632 | { |
1633 | mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); | |
1634 | return mask; | |
1635 | } | |
3b7391de | 1636 | |
71fe97e1 | 1637 | static int prctl_set_mm_exe_file_locked(struct mm_struct *mm, unsigned int fd) |
b32dfe37 | 1638 | { |
2903ff01 | 1639 | struct fd exe; |
496ad9aa | 1640 | struct inode *inode; |
2903ff01 | 1641 | int err; |
b32dfe37 | 1642 | |
96dad67f | 1643 | VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_sem), mm); |
71fe97e1 | 1644 | |
2903ff01 AV |
1645 | exe = fdget(fd); |
1646 | if (!exe.file) | |
b32dfe37 CG |
1647 | return -EBADF; |
1648 | ||
496ad9aa | 1649 | inode = file_inode(exe.file); |
b32dfe37 CG |
1650 | |
1651 | /* | |
1652 | * Because the original mm->exe_file points to executable file, make | |
1653 | * sure that this one is executable as well, to avoid breaking an | |
1654 | * overall picture. | |
1655 | */ | |
1656 | err = -EACCES; | |
496ad9aa | 1657 | if (!S_ISREG(inode->i_mode) || |
2903ff01 | 1658 | exe.file->f_path.mnt->mnt_flags & MNT_NOEXEC) |
b32dfe37 CG |
1659 | goto exit; |
1660 | ||
496ad9aa | 1661 | err = inode_permission(inode, MAY_EXEC); |
b32dfe37 CG |
1662 | if (err) |
1663 | goto exit; | |
1664 | ||
bafb282d | 1665 | /* |
4229fb1d | 1666 | * Forbid mm->exe_file change if old file still mapped. |
bafb282d KK |
1667 | */ |
1668 | err = -EBUSY; | |
4229fb1d KK |
1669 | if (mm->exe_file) { |
1670 | struct vm_area_struct *vma; | |
1671 | ||
1672 | for (vma = mm->mmap; vma; vma = vma->vm_next) | |
1673 | if (vma->vm_file && | |
1674 | path_equal(&vma->vm_file->f_path, | |
1675 | &mm->exe_file->f_path)) | |
71fe97e1 | 1676 | goto exit; |
bafb282d KK |
1677 | } |
1678 | ||
b32dfe37 CG |
1679 | /* |
1680 | * The symlink can be changed only once, just to disallow arbitrary | |
1681 | * transitions malicious software might bring in. This means one | |
1682 | * could make a snapshot over all processes running and monitor | |
1683 | * /proc/pid/exe changes to notice unusual activity if needed. | |
1684 | */ | |
bafb282d KK |
1685 | err = -EPERM; |
1686 | if (test_and_set_bit(MMF_EXE_FILE_CHANGED, &mm->flags)) | |
71fe97e1 | 1687 | goto exit; |
bafb282d | 1688 | |
4229fb1d | 1689 | err = 0; |
2903ff01 | 1690 | set_mm_exe_file(mm, exe.file); /* this grabs a reference to exe.file */ |
b32dfe37 | 1691 | exit: |
2903ff01 | 1692 | fdput(exe); |
b32dfe37 CG |
1693 | return err; |
1694 | } | |
1695 | ||
f606b77f CG |
1696 | #ifdef CONFIG_CHECKPOINT_RESTORE |
1697 | /* | |
1698 | * WARNING: we don't require any capability here so be very careful | |
1699 | * in what is allowed for modification from userspace. | |
1700 | */ | |
1701 | static int validate_prctl_map(struct prctl_mm_map *prctl_map) | |
1702 | { | |
1703 | unsigned long mmap_max_addr = TASK_SIZE; | |
1704 | struct mm_struct *mm = current->mm; | |
1705 | int error = -EINVAL, i; | |
1706 | ||
1707 | static const unsigned char offsets[] = { | |
1708 | offsetof(struct prctl_mm_map, start_code), | |
1709 | offsetof(struct prctl_mm_map, end_code), | |
1710 | offsetof(struct prctl_mm_map, start_data), | |
1711 | offsetof(struct prctl_mm_map, end_data), | |
1712 | offsetof(struct prctl_mm_map, start_brk), | |
1713 | offsetof(struct prctl_mm_map, brk), | |
1714 | offsetof(struct prctl_mm_map, start_stack), | |
1715 | offsetof(struct prctl_mm_map, arg_start), | |
1716 | offsetof(struct prctl_mm_map, arg_end), | |
1717 | offsetof(struct prctl_mm_map, env_start), | |
1718 | offsetof(struct prctl_mm_map, env_end), | |
1719 | }; | |
1720 | ||
1721 | /* | |
1722 | * Make sure the members are not somewhere outside | |
1723 | * of allowed address space. | |
1724 | */ | |
1725 | for (i = 0; i < ARRAY_SIZE(offsets); i++) { | |
1726 | u64 val = *(u64 *)((char *)prctl_map + offsets[i]); | |
1727 | ||
1728 | if ((unsigned long)val >= mmap_max_addr || | |
1729 | (unsigned long)val < mmap_min_addr) | |
1730 | goto out; | |
1731 | } | |
1732 | ||
1733 | /* | |
1734 | * Make sure the pairs are ordered. | |
1735 | */ | |
1736 | #define __prctl_check_order(__m1, __op, __m2) \ | |
1737 | ((unsigned long)prctl_map->__m1 __op \ | |
1738 | (unsigned long)prctl_map->__m2) ? 0 : -EINVAL | |
1739 | error = __prctl_check_order(start_code, <, end_code); | |
1740 | error |= __prctl_check_order(start_data, <, end_data); | |
1741 | error |= __prctl_check_order(start_brk, <=, brk); | |
1742 | error |= __prctl_check_order(arg_start, <=, arg_end); | |
1743 | error |= __prctl_check_order(env_start, <=, env_end); | |
1744 | if (error) | |
1745 | goto out; | |
1746 | #undef __prctl_check_order | |
1747 | ||
1748 | error = -EINVAL; | |
1749 | ||
1750 | /* | |
1751 | * @brk should be after @end_data in traditional maps. | |
1752 | */ | |
1753 | if (prctl_map->start_brk <= prctl_map->end_data || | |
1754 | prctl_map->brk <= prctl_map->end_data) | |
1755 | goto out; | |
1756 | ||
1757 | /* | |
1758 | * Neither we should allow to override limits if they set. | |
1759 | */ | |
1760 | if (check_data_rlimit(rlimit(RLIMIT_DATA), prctl_map->brk, | |
1761 | prctl_map->start_brk, prctl_map->end_data, | |
1762 | prctl_map->start_data)) | |
1763 | goto out; | |
1764 | ||
1765 | /* | |
1766 | * Someone is trying to cheat the auxv vector. | |
1767 | */ | |
1768 | if (prctl_map->auxv_size) { | |
1769 | if (!prctl_map->auxv || prctl_map->auxv_size > sizeof(mm->saved_auxv)) | |
1770 | goto out; | |
1771 | } | |
1772 | ||
1773 | /* | |
1774 | * Finally, make sure the caller has the rights to | |
1775 | * change /proc/pid/exe link: only local root should | |
1776 | * be allowed to. | |
1777 | */ | |
1778 | if (prctl_map->exe_fd != (u32)-1) { | |
1779 | struct user_namespace *ns = current_user_ns(); | |
1780 | const struct cred *cred = current_cred(); | |
1781 | ||
1782 | if (!uid_eq(cred->uid, make_kuid(ns, 0)) || | |
1783 | !gid_eq(cred->gid, make_kgid(ns, 0))) | |
1784 | goto out; | |
1785 | } | |
1786 | ||
1787 | error = 0; | |
1788 | out: | |
1789 | return error; | |
1790 | } | |
1791 | ||
1792 | static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size) | |
1793 | { | |
1794 | struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, }; | |
1795 | unsigned long user_auxv[AT_VECTOR_SIZE]; | |
1796 | struct mm_struct *mm = current->mm; | |
1797 | int error; | |
1798 | ||
1799 | BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); | |
1800 | BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256); | |
1801 | ||
1802 | if (opt == PR_SET_MM_MAP_SIZE) | |
1803 | return put_user((unsigned int)sizeof(prctl_map), | |
1804 | (unsigned int __user *)addr); | |
1805 | ||
1806 | if (data_size != sizeof(prctl_map)) | |
1807 | return -EINVAL; | |
1808 | ||
1809 | if (copy_from_user(&prctl_map, addr, sizeof(prctl_map))) | |
1810 | return -EFAULT; | |
1811 | ||
1812 | error = validate_prctl_map(&prctl_map); | |
1813 | if (error) | |
1814 | return error; | |
1815 | ||
1816 | if (prctl_map.auxv_size) { | |
1817 | memset(user_auxv, 0, sizeof(user_auxv)); | |
1818 | if (copy_from_user(user_auxv, | |
1819 | (const void __user *)prctl_map.auxv, | |
1820 | prctl_map.auxv_size)) | |
1821 | return -EFAULT; | |
1822 | ||
1823 | /* Last entry must be AT_NULL as specification requires */ | |
1824 | user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL; | |
1825 | user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL; | |
1826 | } | |
1827 | ||
1828 | down_write(&mm->mmap_sem); | |
1829 | if (prctl_map.exe_fd != (u32)-1) | |
1830 | error = prctl_set_mm_exe_file_locked(mm, prctl_map.exe_fd); | |
1831 | downgrade_write(&mm->mmap_sem); | |
1832 | if (error) | |
1833 | goto out; | |
1834 | ||
1835 | /* | |
1836 | * We don't validate if these members are pointing to | |
1837 | * real present VMAs because application may have correspond | |
1838 | * VMAs already unmapped and kernel uses these members for statistics | |
1839 | * output in procfs mostly, except | |
1840 | * | |
1841 | * - @start_brk/@brk which are used in do_brk but kernel lookups | |
1842 | * for VMAs when updating these memvers so anything wrong written | |
1843 | * here cause kernel to swear at userspace program but won't lead | |
1844 | * to any problem in kernel itself | |
1845 | */ | |
1846 | ||
1847 | mm->start_code = prctl_map.start_code; | |
1848 | mm->end_code = prctl_map.end_code; | |
1849 | mm->start_data = prctl_map.start_data; | |
1850 | mm->end_data = prctl_map.end_data; | |
1851 | mm->start_brk = prctl_map.start_brk; | |
1852 | mm->brk = prctl_map.brk; | |
1853 | mm->start_stack = prctl_map.start_stack; | |
1854 | mm->arg_start = prctl_map.arg_start; | |
1855 | mm->arg_end = prctl_map.arg_end; | |
1856 | mm->env_start = prctl_map.env_start; | |
1857 | mm->env_end = prctl_map.env_end; | |
1858 | ||
1859 | /* | |
1860 | * Note this update of @saved_auxv is lockless thus | |
1861 | * if someone reads this member in procfs while we're | |
1862 | * updating -- it may get partly updated results. It's | |
1863 | * known and acceptable trade off: we leave it as is to | |
1864 | * not introduce additional locks here making the kernel | |
1865 | * more complex. | |
1866 | */ | |
1867 | if (prctl_map.auxv_size) | |
1868 | memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv)); | |
1869 | ||
1870 | error = 0; | |
1871 | out: | |
1872 | up_read(&mm->mmap_sem); | |
1873 | return error; | |
1874 | } | |
1875 | #endif /* CONFIG_CHECKPOINT_RESTORE */ | |
1876 | ||
028ee4be CG |
1877 | static int prctl_set_mm(int opt, unsigned long addr, |
1878 | unsigned long arg4, unsigned long arg5) | |
1879 | { | |
028ee4be | 1880 | struct mm_struct *mm = current->mm; |
fe8c7f5c CG |
1881 | struct vm_area_struct *vma; |
1882 | int error; | |
028ee4be | 1883 | |
f606b77f CG |
1884 | if (arg5 || (arg4 && (opt != PR_SET_MM_AUXV && |
1885 | opt != PR_SET_MM_MAP && | |
1886 | opt != PR_SET_MM_MAP_SIZE))) | |
028ee4be CG |
1887 | return -EINVAL; |
1888 | ||
f606b77f CG |
1889 | #ifdef CONFIG_CHECKPOINT_RESTORE |
1890 | if (opt == PR_SET_MM_MAP || opt == PR_SET_MM_MAP_SIZE) | |
1891 | return prctl_set_mm_map(opt, (const void __user *)addr, arg4); | |
1892 | #endif | |
1893 | ||
79f0713d | 1894 | if (!capable(CAP_SYS_RESOURCE)) |
028ee4be CG |
1895 | return -EPERM; |
1896 | ||
71fe97e1 CG |
1897 | if (opt == PR_SET_MM_EXE_FILE) { |
1898 | down_write(&mm->mmap_sem); | |
1899 | error = prctl_set_mm_exe_file_locked(mm, (unsigned int)addr); | |
1900 | up_write(&mm->mmap_sem); | |
1901 | return error; | |
1902 | } | |
b32dfe37 | 1903 | |
1ad75b9e | 1904 | if (addr >= TASK_SIZE || addr < mmap_min_addr) |
028ee4be CG |
1905 | return -EINVAL; |
1906 | ||
fe8c7f5c CG |
1907 | error = -EINVAL; |
1908 | ||
028ee4be CG |
1909 | down_read(&mm->mmap_sem); |
1910 | vma = find_vma(mm, addr); | |
1911 | ||
028ee4be CG |
1912 | switch (opt) { |
1913 | case PR_SET_MM_START_CODE: | |
fe8c7f5c CG |
1914 | mm->start_code = addr; |
1915 | break; | |
028ee4be | 1916 | case PR_SET_MM_END_CODE: |
fe8c7f5c | 1917 | mm->end_code = addr; |
028ee4be | 1918 | break; |
028ee4be | 1919 | case PR_SET_MM_START_DATA: |
fe8c7f5c | 1920 | mm->start_data = addr; |
028ee4be | 1921 | break; |
fe8c7f5c CG |
1922 | case PR_SET_MM_END_DATA: |
1923 | mm->end_data = addr; | |
028ee4be CG |
1924 | break; |
1925 | ||
1926 | case PR_SET_MM_START_BRK: | |
1927 | if (addr <= mm->end_data) | |
1928 | goto out; | |
1929 | ||
8764b338 CG |
1930 | if (check_data_rlimit(rlimit(RLIMIT_DATA), mm->brk, addr, |
1931 | mm->end_data, mm->start_data)) | |
028ee4be CG |
1932 | goto out; |
1933 | ||
1934 | mm->start_brk = addr; | |
1935 | break; | |
1936 | ||
1937 | case PR_SET_MM_BRK: | |
1938 | if (addr <= mm->end_data) | |
1939 | goto out; | |
1940 | ||
8764b338 CG |
1941 | if (check_data_rlimit(rlimit(RLIMIT_DATA), addr, mm->start_brk, |
1942 | mm->end_data, mm->start_data)) | |
028ee4be CG |
1943 | goto out; |
1944 | ||
1945 | mm->brk = addr; | |
1946 | break; | |
1947 | ||
fe8c7f5c CG |
1948 | /* |
1949 | * If command line arguments and environment | |
1950 | * are placed somewhere else on stack, we can | |
1951 | * set them up here, ARG_START/END to setup | |
1952 | * command line argumets and ENV_START/END | |
1953 | * for environment. | |
1954 | */ | |
1955 | case PR_SET_MM_START_STACK: | |
1956 | case PR_SET_MM_ARG_START: | |
1957 | case PR_SET_MM_ARG_END: | |
1958 | case PR_SET_MM_ENV_START: | |
1959 | case PR_SET_MM_ENV_END: | |
1960 | if (!vma) { | |
1961 | error = -EFAULT; | |
1962 | goto out; | |
1963 | } | |
fe8c7f5c CG |
1964 | if (opt == PR_SET_MM_START_STACK) |
1965 | mm->start_stack = addr; | |
1966 | else if (opt == PR_SET_MM_ARG_START) | |
1967 | mm->arg_start = addr; | |
1968 | else if (opt == PR_SET_MM_ARG_END) | |
1969 | mm->arg_end = addr; | |
1970 | else if (opt == PR_SET_MM_ENV_START) | |
1971 | mm->env_start = addr; | |
1972 | else if (opt == PR_SET_MM_ENV_END) | |
1973 | mm->env_end = addr; | |
1974 | break; | |
1975 | ||
1976 | /* | |
1977 | * This doesn't move auxiliary vector itself | |
1978 | * since it's pinned to mm_struct, but allow | |
1979 | * to fill vector with new values. It's up | |
1980 | * to a caller to provide sane values here | |
1981 | * otherwise user space tools which use this | |
1982 | * vector might be unhappy. | |
1983 | */ | |
1984 | case PR_SET_MM_AUXV: { | |
1985 | unsigned long user_auxv[AT_VECTOR_SIZE]; | |
1986 | ||
1987 | if (arg4 > sizeof(user_auxv)) | |
1988 | goto out; | |
1989 | up_read(&mm->mmap_sem); | |
1990 | ||
1991 | if (copy_from_user(user_auxv, (const void __user *)addr, arg4)) | |
1992 | return -EFAULT; | |
1993 | ||
1994 | /* Make sure the last entry is always AT_NULL */ | |
1995 | user_auxv[AT_VECTOR_SIZE - 2] = 0; | |
1996 | user_auxv[AT_VECTOR_SIZE - 1] = 0; | |
1997 | ||
1998 | BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); | |
1999 | ||
2000 | task_lock(current); | |
2001 | memcpy(mm->saved_auxv, user_auxv, arg4); | |
2002 | task_unlock(current); | |
2003 | ||
2004 | return 0; | |
2005 | } | |
028ee4be | 2006 | default: |
028ee4be CG |
2007 | goto out; |
2008 | } | |
2009 | ||
2010 | error = 0; | |
028ee4be CG |
2011 | out: |
2012 | up_read(&mm->mmap_sem); | |
028ee4be CG |
2013 | return error; |
2014 | } | |
300f786b | 2015 | |
52b36941 | 2016 | #ifdef CONFIG_CHECKPOINT_RESTORE |
300f786b CG |
2017 | static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr) |
2018 | { | |
2019 | return put_user(me->clear_child_tid, tid_addr); | |
2020 | } | |
52b36941 | 2021 | #else |
300f786b CG |
2022 | static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr) |
2023 | { | |
2024 | return -EINVAL; | |
2025 | } | |
028ee4be CG |
2026 | #endif |
2027 | ||
c4ea37c2 HC |
2028 | SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, |
2029 | unsigned long, arg4, unsigned long, arg5) | |
1da177e4 | 2030 | { |
b6dff3ec DH |
2031 | struct task_struct *me = current; |
2032 | unsigned char comm[sizeof(me->comm)]; | |
2033 | long error; | |
1da177e4 | 2034 | |
d84f4f99 DH |
2035 | error = security_task_prctl(option, arg2, arg3, arg4, arg5); |
2036 | if (error != -ENOSYS) | |
1da177e4 LT |
2037 | return error; |
2038 | ||
d84f4f99 | 2039 | error = 0; |
1da177e4 | 2040 | switch (option) { |
f3cbd435 AM |
2041 | case PR_SET_PDEATHSIG: |
2042 | if (!valid_signal(arg2)) { | |
2043 | error = -EINVAL; | |
1da177e4 | 2044 | break; |
f3cbd435 AM |
2045 | } |
2046 | me->pdeath_signal = arg2; | |
2047 | break; | |
2048 | case PR_GET_PDEATHSIG: | |
2049 | error = put_user(me->pdeath_signal, (int __user *)arg2); | |
2050 | break; | |
2051 | case PR_GET_DUMPABLE: | |
2052 | error = get_dumpable(me->mm); | |
2053 | break; | |
2054 | case PR_SET_DUMPABLE: | |
2055 | if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) { | |
2056 | error = -EINVAL; | |
1da177e4 | 2057 | break; |
f3cbd435 AM |
2058 | } |
2059 | set_dumpable(me->mm, arg2); | |
2060 | break; | |
1da177e4 | 2061 | |
f3cbd435 AM |
2062 | case PR_SET_UNALIGN: |
2063 | error = SET_UNALIGN_CTL(me, arg2); | |
2064 | break; | |
2065 | case PR_GET_UNALIGN: | |
2066 | error = GET_UNALIGN_CTL(me, arg2); | |
2067 | break; | |
2068 | case PR_SET_FPEMU: | |
2069 | error = SET_FPEMU_CTL(me, arg2); | |
2070 | break; | |
2071 | case PR_GET_FPEMU: | |
2072 | error = GET_FPEMU_CTL(me, arg2); | |
2073 | break; | |
2074 | case PR_SET_FPEXC: | |
2075 | error = SET_FPEXC_CTL(me, arg2); | |
2076 | break; | |
2077 | case PR_GET_FPEXC: | |
2078 | error = GET_FPEXC_CTL(me, arg2); | |
2079 | break; | |
2080 | case PR_GET_TIMING: | |
2081 | error = PR_TIMING_STATISTICAL; | |
2082 | break; | |
2083 | case PR_SET_TIMING: | |
2084 | if (arg2 != PR_TIMING_STATISTICAL) | |
2085 | error = -EINVAL; | |
2086 | break; | |
2087 | case PR_SET_NAME: | |
2088 | comm[sizeof(me->comm) - 1] = 0; | |
2089 | if (strncpy_from_user(comm, (char __user *)arg2, | |
2090 | sizeof(me->comm) - 1) < 0) | |
2091 | return -EFAULT; | |
2092 | set_task_comm(me, comm); | |
2093 | proc_comm_connector(me); | |
2094 | break; | |
2095 | case PR_GET_NAME: | |
2096 | get_task_comm(comm, me); | |
2097 | if (copy_to_user((char __user *)arg2, comm, sizeof(comm))) | |
2098 | return -EFAULT; | |
2099 | break; | |
2100 | case PR_GET_ENDIAN: | |
2101 | error = GET_ENDIAN(me, arg2); | |
2102 | break; | |
2103 | case PR_SET_ENDIAN: | |
2104 | error = SET_ENDIAN(me, arg2); | |
2105 | break; | |
2106 | case PR_GET_SECCOMP: | |
2107 | error = prctl_get_seccomp(); | |
2108 | break; | |
2109 | case PR_SET_SECCOMP: | |
2110 | error = prctl_set_seccomp(arg2, (char __user *)arg3); | |
2111 | break; | |
2112 | case PR_GET_TSC: | |
2113 | error = GET_TSC_CTL(arg2); | |
2114 | break; | |
2115 | case PR_SET_TSC: | |
2116 | error = SET_TSC_CTL(arg2); | |
2117 | break; | |
2118 | case PR_TASK_PERF_EVENTS_DISABLE: | |
2119 | error = perf_event_task_disable(); | |
2120 | break; | |
2121 | case PR_TASK_PERF_EVENTS_ENABLE: | |
2122 | error = perf_event_task_enable(); | |
2123 | break; | |
2124 | case PR_GET_TIMERSLACK: | |
2125 | error = current->timer_slack_ns; | |
2126 | break; | |
2127 | case PR_SET_TIMERSLACK: | |
2128 | if (arg2 <= 0) | |
2129 | current->timer_slack_ns = | |
6976675d | 2130 | current->default_timer_slack_ns; |
f3cbd435 AM |
2131 | else |
2132 | current->timer_slack_ns = arg2; | |
2133 | break; | |
2134 | case PR_MCE_KILL: | |
2135 | if (arg4 | arg5) | |
2136 | return -EINVAL; | |
2137 | switch (arg2) { | |
2138 | case PR_MCE_KILL_CLEAR: | |
2139 | if (arg3 != 0) | |
4db96cf0 | 2140 | return -EINVAL; |
f3cbd435 | 2141 | current->flags &= ~PF_MCE_PROCESS; |
4db96cf0 | 2142 | break; |
f3cbd435 AM |
2143 | case PR_MCE_KILL_SET: |
2144 | current->flags |= PF_MCE_PROCESS; | |
2145 | if (arg3 == PR_MCE_KILL_EARLY) | |
2146 | current->flags |= PF_MCE_EARLY; | |
2147 | else if (arg3 == PR_MCE_KILL_LATE) | |
2148 | current->flags &= ~PF_MCE_EARLY; | |
2149 | else if (arg3 == PR_MCE_KILL_DEFAULT) | |
2150 | current->flags &= | |
2151 | ~(PF_MCE_EARLY|PF_MCE_PROCESS); | |
1087e9b4 | 2152 | else |
259e5e6c | 2153 | return -EINVAL; |
259e5e6c | 2154 | break; |
1da177e4 | 2155 | default: |
f3cbd435 AM |
2156 | return -EINVAL; |
2157 | } | |
2158 | break; | |
2159 | case PR_MCE_KILL_GET: | |
2160 | if (arg2 | arg3 | arg4 | arg5) | |
2161 | return -EINVAL; | |
2162 | if (current->flags & PF_MCE_PROCESS) | |
2163 | error = (current->flags & PF_MCE_EARLY) ? | |
2164 | PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE; | |
2165 | else | |
2166 | error = PR_MCE_KILL_DEFAULT; | |
2167 | break; | |
2168 | case PR_SET_MM: | |
2169 | error = prctl_set_mm(arg2, arg3, arg4, arg5); | |
2170 | break; | |
2171 | case PR_GET_TID_ADDRESS: | |
2172 | error = prctl_get_tid_address(me, (int __user **)arg2); | |
2173 | break; | |
2174 | case PR_SET_CHILD_SUBREAPER: | |
2175 | me->signal->is_child_subreaper = !!arg2; | |
2176 | break; | |
2177 | case PR_GET_CHILD_SUBREAPER: | |
2178 | error = put_user(me->signal->is_child_subreaper, | |
2179 | (int __user *)arg2); | |
2180 | break; | |
2181 | case PR_SET_NO_NEW_PRIVS: | |
2182 | if (arg2 != 1 || arg3 || arg4 || arg5) | |
2183 | return -EINVAL; | |
2184 | ||
1d4457f9 | 2185 | task_set_no_new_privs(current); |
f3cbd435 AM |
2186 | break; |
2187 | case PR_GET_NO_NEW_PRIVS: | |
2188 | if (arg2 || arg3 || arg4 || arg5) | |
2189 | return -EINVAL; | |
1d4457f9 | 2190 | return task_no_new_privs(current) ? 1 : 0; |
a0715cc2 AT |
2191 | case PR_GET_THP_DISABLE: |
2192 | if (arg2 || arg3 || arg4 || arg5) | |
2193 | return -EINVAL; | |
2194 | error = !!(me->mm->def_flags & VM_NOHUGEPAGE); | |
2195 | break; | |
2196 | case PR_SET_THP_DISABLE: | |
2197 | if (arg3 || arg4 || arg5) | |
2198 | return -EINVAL; | |
2199 | down_write(&me->mm->mmap_sem); | |
2200 | if (arg2) | |
2201 | me->mm->def_flags |= VM_NOHUGEPAGE; | |
2202 | else | |
2203 | me->mm->def_flags &= ~VM_NOHUGEPAGE; | |
2204 | up_write(&me->mm->mmap_sem); | |
2205 | break; | |
f3cbd435 AM |
2206 | default: |
2207 | error = -EINVAL; | |
2208 | break; | |
1da177e4 LT |
2209 | } |
2210 | return error; | |
2211 | } | |
3cfc348b | 2212 | |
836f92ad HC |
2213 | SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep, |
2214 | struct getcpu_cache __user *, unused) | |
3cfc348b AK |
2215 | { |
2216 | int err = 0; | |
2217 | int cpu = raw_smp_processor_id(); | |
ec94fc3d | 2218 | |
3cfc348b AK |
2219 | if (cpup) |
2220 | err |= put_user(cpu, cpup); | |
2221 | if (nodep) | |
2222 | err |= put_user(cpu_to_node(cpu), nodep); | |
3cfc348b AK |
2223 | return err ? -EFAULT : 0; |
2224 | } | |
10a0a8d4 | 2225 | |
4a22f166 SR |
2226 | /** |
2227 | * do_sysinfo - fill in sysinfo struct | |
2228 | * @info: pointer to buffer to fill | |
2229 | */ | |
2230 | static int do_sysinfo(struct sysinfo *info) | |
2231 | { | |
2232 | unsigned long mem_total, sav_total; | |
2233 | unsigned int mem_unit, bitcount; | |
2234 | struct timespec tp; | |
2235 | ||
2236 | memset(info, 0, sizeof(struct sysinfo)); | |
2237 | ||
45c64940 | 2238 | get_monotonic_boottime(&tp); |
4a22f166 SR |
2239 | info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0); |
2240 | ||
2241 | get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT); | |
2242 | ||
2243 | info->procs = nr_threads; | |
2244 | ||
2245 | si_meminfo(info); | |
2246 | si_swapinfo(info); | |
2247 | ||
2248 | /* | |
2249 | * If the sum of all the available memory (i.e. ram + swap) | |
2250 | * is less than can be stored in a 32 bit unsigned long then | |
2251 | * we can be binary compatible with 2.2.x kernels. If not, | |
2252 | * well, in that case 2.2.x was broken anyways... | |
2253 | * | |
2254 | * -Erik Andersen <andersee@debian.org> | |
2255 | */ | |
2256 | ||
2257 | mem_total = info->totalram + info->totalswap; | |
2258 | if (mem_total < info->totalram || mem_total < info->totalswap) | |
2259 | goto out; | |
2260 | bitcount = 0; | |
2261 | mem_unit = info->mem_unit; | |
2262 | while (mem_unit > 1) { | |
2263 | bitcount++; | |
2264 | mem_unit >>= 1; | |
2265 | sav_total = mem_total; | |
2266 | mem_total <<= 1; | |
2267 | if (mem_total < sav_total) | |
2268 | goto out; | |
2269 | } | |
2270 | ||
2271 | /* | |
2272 | * If mem_total did not overflow, multiply all memory values by | |
2273 | * info->mem_unit and set it to 1. This leaves things compatible | |
2274 | * with 2.2.x, and also retains compatibility with earlier 2.4.x | |
2275 | * kernels... | |
2276 | */ | |
2277 | ||
2278 | info->mem_unit = 1; | |
2279 | info->totalram <<= bitcount; | |
2280 | info->freeram <<= bitcount; | |
2281 | info->sharedram <<= bitcount; | |
2282 | info->bufferram <<= bitcount; | |
2283 | info->totalswap <<= bitcount; | |
2284 | info->freeswap <<= bitcount; | |
2285 | info->totalhigh <<= bitcount; | |
2286 | info->freehigh <<= bitcount; | |
2287 | ||
2288 | out: | |
2289 | return 0; | |
2290 | } | |
2291 | ||
2292 | SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info) | |
2293 | { | |
2294 | struct sysinfo val; | |
2295 | ||
2296 | do_sysinfo(&val); | |
2297 | ||
2298 | if (copy_to_user(info, &val, sizeof(struct sysinfo))) | |
2299 | return -EFAULT; | |
2300 | ||
2301 | return 0; | |
2302 | } | |
2303 | ||
2304 | #ifdef CONFIG_COMPAT | |
2305 | struct compat_sysinfo { | |
2306 | s32 uptime; | |
2307 | u32 loads[3]; | |
2308 | u32 totalram; | |
2309 | u32 freeram; | |
2310 | u32 sharedram; | |
2311 | u32 bufferram; | |
2312 | u32 totalswap; | |
2313 | u32 freeswap; | |
2314 | u16 procs; | |
2315 | u16 pad; | |
2316 | u32 totalhigh; | |
2317 | u32 freehigh; | |
2318 | u32 mem_unit; | |
2319 | char _f[20-2*sizeof(u32)-sizeof(int)]; | |
2320 | }; | |
2321 | ||
2322 | COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info) | |
2323 | { | |
2324 | struct sysinfo s; | |
2325 | ||
2326 | do_sysinfo(&s); | |
2327 | ||
2328 | /* Check to see if any memory value is too large for 32-bit and scale | |
2329 | * down if needed | |
2330 | */ | |
0baae41e | 2331 | if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) { |
4a22f166 SR |
2332 | int bitcount = 0; |
2333 | ||
2334 | while (s.mem_unit < PAGE_SIZE) { | |
2335 | s.mem_unit <<= 1; | |
2336 | bitcount++; | |
2337 | } | |
2338 | ||
2339 | s.totalram >>= bitcount; | |
2340 | s.freeram >>= bitcount; | |
2341 | s.sharedram >>= bitcount; | |
2342 | s.bufferram >>= bitcount; | |
2343 | s.totalswap >>= bitcount; | |
2344 | s.freeswap >>= bitcount; | |
2345 | s.totalhigh >>= bitcount; | |
2346 | s.freehigh >>= bitcount; | |
2347 | } | |
2348 | ||
2349 | if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) || | |
2350 | __put_user(s.uptime, &info->uptime) || | |
2351 | __put_user(s.loads[0], &info->loads[0]) || | |
2352 | __put_user(s.loads[1], &info->loads[1]) || | |
2353 | __put_user(s.loads[2], &info->loads[2]) || | |
2354 | __put_user(s.totalram, &info->totalram) || | |
2355 | __put_user(s.freeram, &info->freeram) || | |
2356 | __put_user(s.sharedram, &info->sharedram) || | |
2357 | __put_user(s.bufferram, &info->bufferram) || | |
2358 | __put_user(s.totalswap, &info->totalswap) || | |
2359 | __put_user(s.freeswap, &info->freeswap) || | |
2360 | __put_user(s.procs, &info->procs) || | |
2361 | __put_user(s.totalhigh, &info->totalhigh) || | |
2362 | __put_user(s.freehigh, &info->freehigh) || | |
2363 | __put_user(s.mem_unit, &info->mem_unit)) | |
2364 | return -EFAULT; | |
2365 | ||
2366 | return 0; | |
2367 | } | |
2368 | #endif /* CONFIG_COMPAT */ |