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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/kernel/sys.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | */ | |
6 | ||
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 | |
fe3d197f DH |
94 | #ifndef MPX_ENABLE_MANAGEMENT |
95 | # define MPX_ENABLE_MANAGEMENT(a) (-EINVAL) | |
96 | #endif | |
97 | #ifndef MPX_DISABLE_MANAGEMENT | |
98 | # define MPX_DISABLE_MANAGEMENT(a) (-EINVAL) | |
99 | #endif | |
9791554b PB |
100 | #ifndef GET_FP_MODE |
101 | # define GET_FP_MODE(a) (-EINVAL) | |
102 | #endif | |
103 | #ifndef SET_FP_MODE | |
104 | # define SET_FP_MODE(a,b) (-EINVAL) | |
105 | #endif | |
1da177e4 LT |
106 | |
107 | /* | |
108 | * this is where the system-wide overflow UID and GID are defined, for | |
109 | * architectures that now have 32-bit UID/GID but didn't in the past | |
110 | */ | |
111 | ||
112 | int overflowuid = DEFAULT_OVERFLOWUID; | |
113 | int overflowgid = DEFAULT_OVERFLOWGID; | |
114 | ||
1da177e4 LT |
115 | EXPORT_SYMBOL(overflowuid); |
116 | EXPORT_SYMBOL(overflowgid); | |
1da177e4 LT |
117 | |
118 | /* | |
119 | * the same as above, but for filesystems which can only store a 16-bit | |
120 | * UID and GID. as such, this is needed on all architectures | |
121 | */ | |
122 | ||
123 | int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; | |
124 | int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; | |
125 | ||
126 | EXPORT_SYMBOL(fs_overflowuid); | |
127 | EXPORT_SYMBOL(fs_overflowgid); | |
128 | ||
fc832ad3 SH |
129 | /* |
130 | * Returns true if current's euid is same as p's uid or euid, | |
131 | * or has CAP_SYS_NICE to p's user_ns. | |
132 | * | |
133 | * Called with rcu_read_lock, creds are safe | |
134 | */ | |
135 | static bool set_one_prio_perm(struct task_struct *p) | |
136 | { | |
137 | const struct cred *cred = current_cred(), *pcred = __task_cred(p); | |
138 | ||
5af66203 EB |
139 | if (uid_eq(pcred->uid, cred->euid) || |
140 | uid_eq(pcred->euid, cred->euid)) | |
fc832ad3 | 141 | return true; |
c4a4d603 | 142 | if (ns_capable(pcred->user_ns, CAP_SYS_NICE)) |
fc832ad3 SH |
143 | return true; |
144 | return false; | |
145 | } | |
146 | ||
c69e8d9c DH |
147 | /* |
148 | * set the priority of a task | |
149 | * - the caller must hold the RCU read lock | |
150 | */ | |
1da177e4 LT |
151 | static int set_one_prio(struct task_struct *p, int niceval, int error) |
152 | { | |
153 | int no_nice; | |
154 | ||
fc832ad3 | 155 | if (!set_one_prio_perm(p)) { |
1da177e4 LT |
156 | error = -EPERM; |
157 | goto out; | |
158 | } | |
e43379f1 | 159 | if (niceval < task_nice(p) && !can_nice(p, niceval)) { |
1da177e4 LT |
160 | error = -EACCES; |
161 | goto out; | |
162 | } | |
163 | no_nice = security_task_setnice(p, niceval); | |
164 | if (no_nice) { | |
165 | error = no_nice; | |
166 | goto out; | |
167 | } | |
168 | if (error == -ESRCH) | |
169 | error = 0; | |
170 | set_user_nice(p, niceval); | |
171 | out: | |
172 | return error; | |
173 | } | |
174 | ||
754fe8d2 | 175 | SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval) |
1da177e4 LT |
176 | { |
177 | struct task_struct *g, *p; | |
178 | struct user_struct *user; | |
86a264ab | 179 | const struct cred *cred = current_cred(); |
1da177e4 | 180 | int error = -EINVAL; |
41487c65 | 181 | struct pid *pgrp; |
7b44ab97 | 182 | kuid_t uid; |
1da177e4 | 183 | |
3e88c553 | 184 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
185 | goto out; |
186 | ||
187 | /* normalize: avoid signed division (rounding problems) */ | |
188 | error = -ESRCH; | |
c4a4d2f4 DY |
189 | if (niceval < MIN_NICE) |
190 | niceval = MIN_NICE; | |
191 | if (niceval > MAX_NICE) | |
192 | niceval = MAX_NICE; | |
1da177e4 | 193 | |
d4581a23 | 194 | rcu_read_lock(); |
1da177e4 LT |
195 | read_lock(&tasklist_lock); |
196 | switch (which) { | |
ec94fc3d | 197 | case PRIO_PROCESS: |
198 | if (who) | |
199 | p = find_task_by_vpid(who); | |
200 | else | |
201 | p = current; | |
202 | if (p) | |
203 | error = set_one_prio(p, niceval, error); | |
204 | break; | |
205 | case PRIO_PGRP: | |
206 | if (who) | |
207 | pgrp = find_vpid(who); | |
208 | else | |
209 | pgrp = task_pgrp(current); | |
210 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { | |
211 | error = set_one_prio(p, niceval, error); | |
212 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); | |
213 | break; | |
214 | case PRIO_USER: | |
215 | uid = make_kuid(cred->user_ns, who); | |
216 | user = cred->user; | |
217 | if (!who) | |
218 | uid = cred->uid; | |
219 | else if (!uid_eq(uid, cred->uid)) { | |
220 | user = find_user(uid); | |
221 | if (!user) | |
86a264ab | 222 | goto out_unlock; /* No processes for this user */ |
ec94fc3d | 223 | } |
224 | do_each_thread(g, p) { | |
225 | if (uid_eq(task_uid(p), uid)) | |
226 | error = set_one_prio(p, niceval, error); | |
227 | } while_each_thread(g, p); | |
228 | if (!uid_eq(uid, cred->uid)) | |
229 | free_uid(user); /* For find_user() */ | |
230 | break; | |
1da177e4 LT |
231 | } |
232 | out_unlock: | |
233 | read_unlock(&tasklist_lock); | |
d4581a23 | 234 | rcu_read_unlock(); |
1da177e4 LT |
235 | out: |
236 | return error; | |
237 | } | |
238 | ||
239 | /* | |
240 | * Ugh. To avoid negative return values, "getpriority()" will | |
241 | * not return the normal nice-value, but a negated value that | |
242 | * has been offset by 20 (ie it returns 40..1 instead of -20..19) | |
243 | * to stay compatible. | |
244 | */ | |
754fe8d2 | 245 | SYSCALL_DEFINE2(getpriority, int, which, int, who) |
1da177e4 LT |
246 | { |
247 | struct task_struct *g, *p; | |
248 | struct user_struct *user; | |
86a264ab | 249 | const struct cred *cred = current_cred(); |
1da177e4 | 250 | long niceval, retval = -ESRCH; |
41487c65 | 251 | struct pid *pgrp; |
7b44ab97 | 252 | kuid_t uid; |
1da177e4 | 253 | |
3e88c553 | 254 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
255 | return -EINVAL; |
256 | ||
70118837 | 257 | rcu_read_lock(); |
1da177e4 LT |
258 | read_lock(&tasklist_lock); |
259 | switch (which) { | |
ec94fc3d | 260 | case PRIO_PROCESS: |
261 | if (who) | |
262 | p = find_task_by_vpid(who); | |
263 | else | |
264 | p = current; | |
265 | if (p) { | |
266 | niceval = nice_to_rlimit(task_nice(p)); | |
267 | if (niceval > retval) | |
268 | retval = niceval; | |
269 | } | |
270 | break; | |
271 | case PRIO_PGRP: | |
272 | if (who) | |
273 | pgrp = find_vpid(who); | |
274 | else | |
275 | pgrp = task_pgrp(current); | |
276 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { | |
277 | niceval = nice_to_rlimit(task_nice(p)); | |
278 | if (niceval > retval) | |
279 | retval = niceval; | |
280 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); | |
281 | break; | |
282 | case PRIO_USER: | |
283 | uid = make_kuid(cred->user_ns, who); | |
284 | user = cred->user; | |
285 | if (!who) | |
286 | uid = cred->uid; | |
287 | else if (!uid_eq(uid, cred->uid)) { | |
288 | user = find_user(uid); | |
289 | if (!user) | |
290 | goto out_unlock; /* No processes for this user */ | |
291 | } | |
292 | do_each_thread(g, p) { | |
293 | if (uid_eq(task_uid(p), uid)) { | |
7aa2c016 | 294 | niceval = nice_to_rlimit(task_nice(p)); |
1da177e4 LT |
295 | if (niceval > retval) |
296 | retval = niceval; | |
297 | } | |
ec94fc3d | 298 | } while_each_thread(g, p); |
299 | if (!uid_eq(uid, cred->uid)) | |
300 | free_uid(user); /* for find_user() */ | |
301 | break; | |
1da177e4 LT |
302 | } |
303 | out_unlock: | |
304 | read_unlock(&tasklist_lock); | |
70118837 | 305 | rcu_read_unlock(); |
1da177e4 LT |
306 | |
307 | return retval; | |
308 | } | |
309 | ||
1da177e4 LT |
310 | /* |
311 | * Unprivileged users may change the real gid to the effective gid | |
312 | * or vice versa. (BSD-style) | |
313 | * | |
314 | * If you set the real gid at all, or set the effective gid to a value not | |
315 | * equal to the real gid, then the saved gid is set to the new effective gid. | |
316 | * | |
317 | * This makes it possible for a setgid program to completely drop its | |
318 | * privileges, which is often a useful assertion to make when you are doing | |
319 | * a security audit over a program. | |
320 | * | |
321 | * The general idea is that a program which uses just setregid() will be | |
322 | * 100% compatible with BSD. A program which uses just setgid() will be | |
ec94fc3d | 323 | * 100% compatible with POSIX with saved IDs. |
1da177e4 LT |
324 | * |
325 | * SMP: There are not races, the GIDs are checked only by filesystem | |
326 | * operations (as far as semantic preservation is concerned). | |
327 | */ | |
ae1251ab | 328 | SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) |
1da177e4 | 329 | { |
a29c33f4 | 330 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
331 | const struct cred *old; |
332 | struct cred *new; | |
1da177e4 | 333 | int retval; |
a29c33f4 EB |
334 | kgid_t krgid, kegid; |
335 | ||
336 | krgid = make_kgid(ns, rgid); | |
337 | kegid = make_kgid(ns, egid); | |
338 | ||
339 | if ((rgid != (gid_t) -1) && !gid_valid(krgid)) | |
340 | return -EINVAL; | |
341 | if ((egid != (gid_t) -1) && !gid_valid(kegid)) | |
342 | return -EINVAL; | |
1da177e4 | 343 | |
d84f4f99 DH |
344 | new = prepare_creds(); |
345 | if (!new) | |
346 | return -ENOMEM; | |
347 | old = current_cred(); | |
348 | ||
d84f4f99 | 349 | retval = -EPERM; |
1da177e4 | 350 | if (rgid != (gid_t) -1) { |
a29c33f4 EB |
351 | if (gid_eq(old->gid, krgid) || |
352 | gid_eq(old->egid, krgid) || | |
c7b96acf | 353 | ns_capable(old->user_ns, CAP_SETGID)) |
a29c33f4 | 354 | new->gid = krgid; |
1da177e4 | 355 | else |
d84f4f99 | 356 | goto error; |
1da177e4 LT |
357 | } |
358 | if (egid != (gid_t) -1) { | |
a29c33f4 EB |
359 | if (gid_eq(old->gid, kegid) || |
360 | gid_eq(old->egid, kegid) || | |
361 | gid_eq(old->sgid, kegid) || | |
c7b96acf | 362 | ns_capable(old->user_ns, CAP_SETGID)) |
a29c33f4 | 363 | new->egid = kegid; |
756184b7 | 364 | else |
d84f4f99 | 365 | goto error; |
1da177e4 | 366 | } |
d84f4f99 | 367 | |
1da177e4 | 368 | if (rgid != (gid_t) -1 || |
a29c33f4 | 369 | (egid != (gid_t) -1 && !gid_eq(kegid, old->gid))) |
d84f4f99 DH |
370 | new->sgid = new->egid; |
371 | new->fsgid = new->egid; | |
372 | ||
373 | return commit_creds(new); | |
374 | ||
375 | error: | |
376 | abort_creds(new); | |
377 | return retval; | |
1da177e4 LT |
378 | } |
379 | ||
380 | /* | |
ec94fc3d | 381 | * setgid() is implemented like SysV w/ SAVED_IDS |
1da177e4 LT |
382 | * |
383 | * SMP: Same implicit races as above. | |
384 | */ | |
ae1251ab | 385 | SYSCALL_DEFINE1(setgid, gid_t, gid) |
1da177e4 | 386 | { |
a29c33f4 | 387 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
388 | const struct cred *old; |
389 | struct cred *new; | |
1da177e4 | 390 | int retval; |
a29c33f4 EB |
391 | kgid_t kgid; |
392 | ||
393 | kgid = make_kgid(ns, gid); | |
394 | if (!gid_valid(kgid)) | |
395 | return -EINVAL; | |
1da177e4 | 396 | |
d84f4f99 DH |
397 | new = prepare_creds(); |
398 | if (!new) | |
399 | return -ENOMEM; | |
400 | old = current_cred(); | |
401 | ||
d84f4f99 | 402 | retval = -EPERM; |
c7b96acf | 403 | if (ns_capable(old->user_ns, CAP_SETGID)) |
a29c33f4 EB |
404 | new->gid = new->egid = new->sgid = new->fsgid = kgid; |
405 | else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid)) | |
406 | new->egid = new->fsgid = kgid; | |
1da177e4 | 407 | else |
d84f4f99 | 408 | goto error; |
1da177e4 | 409 | |
d84f4f99 DH |
410 | return commit_creds(new); |
411 | ||
412 | error: | |
413 | abort_creds(new); | |
414 | return retval; | |
1da177e4 | 415 | } |
54e99124 | 416 | |
d84f4f99 DH |
417 | /* |
418 | * change the user struct in a credentials set to match the new UID | |
419 | */ | |
420 | static int set_user(struct cred *new) | |
1da177e4 LT |
421 | { |
422 | struct user_struct *new_user; | |
423 | ||
078de5f7 | 424 | new_user = alloc_uid(new->uid); |
1da177e4 LT |
425 | if (!new_user) |
426 | return -EAGAIN; | |
427 | ||
72fa5997 VK |
428 | /* |
429 | * We don't fail in case of NPROC limit excess here because too many | |
430 | * poorly written programs don't check set*uid() return code, assuming | |
431 | * it never fails if called by root. We may still enforce NPROC limit | |
432 | * for programs doing set*uid()+execve() by harmlessly deferring the | |
433 | * failure to the execve() stage. | |
434 | */ | |
78d7d407 | 435 | if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) && |
72fa5997 VK |
436 | new_user != INIT_USER) |
437 | current->flags |= PF_NPROC_EXCEEDED; | |
438 | else | |
439 | current->flags &= ~PF_NPROC_EXCEEDED; | |
1da177e4 | 440 | |
d84f4f99 DH |
441 | free_uid(new->user); |
442 | new->user = new_user; | |
1da177e4 LT |
443 | return 0; |
444 | } | |
445 | ||
446 | /* | |
447 | * Unprivileged users may change the real uid to the effective uid | |
448 | * or vice versa. (BSD-style) | |
449 | * | |
450 | * If you set the real uid at all, or set the effective uid to a value not | |
451 | * equal to the real uid, then the saved uid is set to the new effective uid. | |
452 | * | |
453 | * This makes it possible for a setuid program to completely drop its | |
454 | * privileges, which is often a useful assertion to make when you are doing | |
455 | * a security audit over a program. | |
456 | * | |
457 | * The general idea is that a program which uses just setreuid() will be | |
458 | * 100% compatible with BSD. A program which uses just setuid() will be | |
ec94fc3d | 459 | * 100% compatible with POSIX with saved IDs. |
1da177e4 | 460 | */ |
ae1251ab | 461 | SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) |
1da177e4 | 462 | { |
a29c33f4 | 463 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
464 | const struct cred *old; |
465 | struct cred *new; | |
1da177e4 | 466 | int retval; |
a29c33f4 EB |
467 | kuid_t kruid, keuid; |
468 | ||
469 | kruid = make_kuid(ns, ruid); | |
470 | keuid = make_kuid(ns, euid); | |
471 | ||
472 | if ((ruid != (uid_t) -1) && !uid_valid(kruid)) | |
473 | return -EINVAL; | |
474 | if ((euid != (uid_t) -1) && !uid_valid(keuid)) | |
475 | return -EINVAL; | |
1da177e4 | 476 | |
d84f4f99 DH |
477 | new = prepare_creds(); |
478 | if (!new) | |
479 | return -ENOMEM; | |
480 | old = current_cred(); | |
481 | ||
d84f4f99 | 482 | retval = -EPERM; |
1da177e4 | 483 | if (ruid != (uid_t) -1) { |
a29c33f4 EB |
484 | new->uid = kruid; |
485 | if (!uid_eq(old->uid, kruid) && | |
486 | !uid_eq(old->euid, kruid) && | |
c7b96acf | 487 | !ns_capable(old->user_ns, CAP_SETUID)) |
d84f4f99 | 488 | goto error; |
1da177e4 LT |
489 | } |
490 | ||
491 | if (euid != (uid_t) -1) { | |
a29c33f4 EB |
492 | new->euid = keuid; |
493 | if (!uid_eq(old->uid, keuid) && | |
494 | !uid_eq(old->euid, keuid) && | |
495 | !uid_eq(old->suid, keuid) && | |
c7b96acf | 496 | !ns_capable(old->user_ns, CAP_SETUID)) |
d84f4f99 | 497 | goto error; |
1da177e4 LT |
498 | } |
499 | ||
a29c33f4 | 500 | if (!uid_eq(new->uid, old->uid)) { |
54e99124 DG |
501 | retval = set_user(new); |
502 | if (retval < 0) | |
503 | goto error; | |
504 | } | |
1da177e4 | 505 | if (ruid != (uid_t) -1 || |
a29c33f4 | 506 | (euid != (uid_t) -1 && !uid_eq(keuid, old->uid))) |
d84f4f99 DH |
507 | new->suid = new->euid; |
508 | new->fsuid = new->euid; | |
1da177e4 | 509 | |
d84f4f99 DH |
510 | retval = security_task_fix_setuid(new, old, LSM_SETID_RE); |
511 | if (retval < 0) | |
512 | goto error; | |
1da177e4 | 513 | |
d84f4f99 | 514 | return commit_creds(new); |
1da177e4 | 515 | |
d84f4f99 DH |
516 | error: |
517 | abort_creds(new); | |
518 | return retval; | |
519 | } | |
ec94fc3d | 520 | |
1da177e4 | 521 | /* |
ec94fc3d | 522 | * setuid() is implemented like SysV with SAVED_IDS |
523 | * | |
1da177e4 | 524 | * Note that SAVED_ID's is deficient in that a setuid root program |
ec94fc3d | 525 | * like sendmail, for example, cannot set its uid to be a normal |
1da177e4 LT |
526 | * user and then switch back, because if you're root, setuid() sets |
527 | * the saved uid too. If you don't like this, blame the bright people | |
528 | * in the POSIX committee and/or USG. Note that the BSD-style setreuid() | |
529 | * will allow a root program to temporarily drop privileges and be able to | |
ec94fc3d | 530 | * regain them by swapping the real and effective uid. |
1da177e4 | 531 | */ |
ae1251ab | 532 | SYSCALL_DEFINE1(setuid, uid_t, uid) |
1da177e4 | 533 | { |
a29c33f4 | 534 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
535 | const struct cred *old; |
536 | struct cred *new; | |
1da177e4 | 537 | int retval; |
a29c33f4 EB |
538 | kuid_t kuid; |
539 | ||
540 | kuid = make_kuid(ns, uid); | |
541 | if (!uid_valid(kuid)) | |
542 | return -EINVAL; | |
1da177e4 | 543 | |
d84f4f99 DH |
544 | new = prepare_creds(); |
545 | if (!new) | |
546 | return -ENOMEM; | |
547 | old = current_cred(); | |
548 | ||
d84f4f99 | 549 | retval = -EPERM; |
c7b96acf | 550 | if (ns_capable(old->user_ns, CAP_SETUID)) { |
a29c33f4 EB |
551 | new->suid = new->uid = kuid; |
552 | if (!uid_eq(kuid, old->uid)) { | |
54e99124 DG |
553 | retval = set_user(new); |
554 | if (retval < 0) | |
555 | goto error; | |
d84f4f99 | 556 | } |
a29c33f4 | 557 | } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) { |
d84f4f99 | 558 | goto error; |
1da177e4 | 559 | } |
1da177e4 | 560 | |
a29c33f4 | 561 | new->fsuid = new->euid = kuid; |
d84f4f99 DH |
562 | |
563 | retval = security_task_fix_setuid(new, old, LSM_SETID_ID); | |
564 | if (retval < 0) | |
565 | goto error; | |
1da177e4 | 566 | |
d84f4f99 | 567 | return commit_creds(new); |
1da177e4 | 568 | |
d84f4f99 DH |
569 | error: |
570 | abort_creds(new); | |
571 | return retval; | |
1da177e4 LT |
572 | } |
573 | ||
574 | ||
575 | /* | |
576 | * This function implements a generic ability to update ruid, euid, | |
577 | * and suid. This allows you to implement the 4.4 compatible seteuid(). | |
578 | */ | |
ae1251ab | 579 | SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) |
1da177e4 | 580 | { |
a29c33f4 | 581 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
582 | const struct cred *old; |
583 | struct cred *new; | |
1da177e4 | 584 | int retval; |
a29c33f4 EB |
585 | kuid_t kruid, keuid, ksuid; |
586 | ||
587 | kruid = make_kuid(ns, ruid); | |
588 | keuid = make_kuid(ns, euid); | |
589 | ksuid = make_kuid(ns, suid); | |
590 | ||
591 | if ((ruid != (uid_t) -1) && !uid_valid(kruid)) | |
592 | return -EINVAL; | |
593 | ||
594 | if ((euid != (uid_t) -1) && !uid_valid(keuid)) | |
595 | return -EINVAL; | |
596 | ||
597 | if ((suid != (uid_t) -1) && !uid_valid(ksuid)) | |
598 | return -EINVAL; | |
1da177e4 | 599 | |
d84f4f99 DH |
600 | new = prepare_creds(); |
601 | if (!new) | |
602 | return -ENOMEM; | |
603 | ||
d84f4f99 | 604 | old = current_cred(); |
1da177e4 | 605 | |
d84f4f99 | 606 | retval = -EPERM; |
c7b96acf | 607 | if (!ns_capable(old->user_ns, CAP_SETUID)) { |
a29c33f4 EB |
608 | if (ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) && |
609 | !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid)) | |
d84f4f99 | 610 | goto error; |
a29c33f4 EB |
611 | if (euid != (uid_t) -1 && !uid_eq(keuid, old->uid) && |
612 | !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid)) | |
d84f4f99 | 613 | goto error; |
a29c33f4 EB |
614 | if (suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) && |
615 | !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid)) | |
d84f4f99 | 616 | goto error; |
1da177e4 | 617 | } |
d84f4f99 | 618 | |
1da177e4 | 619 | if (ruid != (uid_t) -1) { |
a29c33f4 EB |
620 | new->uid = kruid; |
621 | if (!uid_eq(kruid, old->uid)) { | |
54e99124 DG |
622 | retval = set_user(new); |
623 | if (retval < 0) | |
624 | goto error; | |
625 | } | |
1da177e4 | 626 | } |
d84f4f99 | 627 | if (euid != (uid_t) -1) |
a29c33f4 | 628 | new->euid = keuid; |
1da177e4 | 629 | if (suid != (uid_t) -1) |
a29c33f4 | 630 | new->suid = ksuid; |
d84f4f99 | 631 | new->fsuid = new->euid; |
1da177e4 | 632 | |
d84f4f99 DH |
633 | retval = security_task_fix_setuid(new, old, LSM_SETID_RES); |
634 | if (retval < 0) | |
635 | goto error; | |
1da177e4 | 636 | |
d84f4f99 | 637 | return commit_creds(new); |
1da177e4 | 638 | |
d84f4f99 DH |
639 | error: |
640 | abort_creds(new); | |
641 | return retval; | |
1da177e4 LT |
642 | } |
643 | ||
a29c33f4 | 644 | SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp) |
1da177e4 | 645 | { |
86a264ab | 646 | const struct cred *cred = current_cred(); |
1da177e4 | 647 | int retval; |
a29c33f4 EB |
648 | uid_t ruid, euid, suid; |
649 | ||
650 | ruid = from_kuid_munged(cred->user_ns, cred->uid); | |
651 | euid = from_kuid_munged(cred->user_ns, cred->euid); | |
652 | suid = from_kuid_munged(cred->user_ns, cred->suid); | |
1da177e4 | 653 | |
ec94fc3d | 654 | retval = put_user(ruid, ruidp); |
655 | if (!retval) { | |
656 | retval = put_user(euid, euidp); | |
657 | if (!retval) | |
658 | return put_user(suid, suidp); | |
659 | } | |
1da177e4 LT |
660 | return retval; |
661 | } | |
662 | ||
663 | /* | |
664 | * Same as above, but for rgid, egid, sgid. | |
665 | */ | |
ae1251ab | 666 | SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) |
1da177e4 | 667 | { |
a29c33f4 | 668 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
669 | const struct cred *old; |
670 | struct cred *new; | |
1da177e4 | 671 | int retval; |
a29c33f4 EB |
672 | kgid_t krgid, kegid, ksgid; |
673 | ||
674 | krgid = make_kgid(ns, rgid); | |
675 | kegid = make_kgid(ns, egid); | |
676 | ksgid = make_kgid(ns, sgid); | |
677 | ||
678 | if ((rgid != (gid_t) -1) && !gid_valid(krgid)) | |
679 | return -EINVAL; | |
680 | if ((egid != (gid_t) -1) && !gid_valid(kegid)) | |
681 | return -EINVAL; | |
682 | if ((sgid != (gid_t) -1) && !gid_valid(ksgid)) | |
683 | return -EINVAL; | |
1da177e4 | 684 | |
d84f4f99 DH |
685 | new = prepare_creds(); |
686 | if (!new) | |
687 | return -ENOMEM; | |
688 | old = current_cred(); | |
689 | ||
d84f4f99 | 690 | retval = -EPERM; |
c7b96acf | 691 | if (!ns_capable(old->user_ns, CAP_SETGID)) { |
a29c33f4 EB |
692 | if (rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) && |
693 | !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid)) | |
d84f4f99 | 694 | goto error; |
a29c33f4 EB |
695 | if (egid != (gid_t) -1 && !gid_eq(kegid, old->gid) && |
696 | !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid)) | |
d84f4f99 | 697 | goto error; |
a29c33f4 EB |
698 | if (sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) && |
699 | !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid)) | |
d84f4f99 | 700 | goto error; |
1da177e4 | 701 | } |
d84f4f99 | 702 | |
1da177e4 | 703 | if (rgid != (gid_t) -1) |
a29c33f4 | 704 | new->gid = krgid; |
d84f4f99 | 705 | if (egid != (gid_t) -1) |
a29c33f4 | 706 | new->egid = kegid; |
1da177e4 | 707 | if (sgid != (gid_t) -1) |
a29c33f4 | 708 | new->sgid = ksgid; |
d84f4f99 | 709 | new->fsgid = new->egid; |
1da177e4 | 710 | |
d84f4f99 DH |
711 | return commit_creds(new); |
712 | ||
713 | error: | |
714 | abort_creds(new); | |
715 | return retval; | |
1da177e4 LT |
716 | } |
717 | ||
a29c33f4 | 718 | SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp) |
1da177e4 | 719 | { |
86a264ab | 720 | const struct cred *cred = current_cred(); |
1da177e4 | 721 | int retval; |
a29c33f4 EB |
722 | gid_t rgid, egid, sgid; |
723 | ||
724 | rgid = from_kgid_munged(cred->user_ns, cred->gid); | |
725 | egid = from_kgid_munged(cred->user_ns, cred->egid); | |
726 | sgid = from_kgid_munged(cred->user_ns, cred->sgid); | |
1da177e4 | 727 | |
ec94fc3d | 728 | retval = put_user(rgid, rgidp); |
729 | if (!retval) { | |
730 | retval = put_user(egid, egidp); | |
731 | if (!retval) | |
732 | retval = put_user(sgid, sgidp); | |
733 | } | |
1da177e4 LT |
734 | |
735 | return retval; | |
736 | } | |
737 | ||
738 | ||
739 | /* | |
740 | * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This | |
741 | * is used for "access()" and for the NFS daemon (letting nfsd stay at | |
742 | * whatever uid it wants to). It normally shadows "euid", except when | |
743 | * explicitly set by setfsuid() or for access.. | |
744 | */ | |
ae1251ab | 745 | SYSCALL_DEFINE1(setfsuid, uid_t, uid) |
1da177e4 | 746 | { |
d84f4f99 DH |
747 | const struct cred *old; |
748 | struct cred *new; | |
749 | uid_t old_fsuid; | |
a29c33f4 EB |
750 | kuid_t kuid; |
751 | ||
752 | old = current_cred(); | |
753 | old_fsuid = from_kuid_munged(old->user_ns, old->fsuid); | |
754 | ||
755 | kuid = make_kuid(old->user_ns, uid); | |
756 | if (!uid_valid(kuid)) | |
757 | return old_fsuid; | |
1da177e4 | 758 | |
d84f4f99 DH |
759 | new = prepare_creds(); |
760 | if (!new) | |
a29c33f4 | 761 | return old_fsuid; |
1da177e4 | 762 | |
a29c33f4 EB |
763 | if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) || |
764 | uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) || | |
c7b96acf | 765 | ns_capable(old->user_ns, CAP_SETUID)) { |
a29c33f4 EB |
766 | if (!uid_eq(kuid, old->fsuid)) { |
767 | new->fsuid = kuid; | |
d84f4f99 DH |
768 | if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) |
769 | goto change_okay; | |
1da177e4 | 770 | } |
1da177e4 LT |
771 | } |
772 | ||
d84f4f99 DH |
773 | abort_creds(new); |
774 | return old_fsuid; | |
1da177e4 | 775 | |
d84f4f99 DH |
776 | change_okay: |
777 | commit_creds(new); | |
1da177e4 LT |
778 | return old_fsuid; |
779 | } | |
780 | ||
781 | /* | |
f42df9e6 | 782 | * Samma på svenska.. |
1da177e4 | 783 | */ |
ae1251ab | 784 | SYSCALL_DEFINE1(setfsgid, gid_t, gid) |
1da177e4 | 785 | { |
d84f4f99 DH |
786 | const struct cred *old; |
787 | struct cred *new; | |
788 | gid_t old_fsgid; | |
a29c33f4 EB |
789 | kgid_t kgid; |
790 | ||
791 | old = current_cred(); | |
792 | old_fsgid = from_kgid_munged(old->user_ns, old->fsgid); | |
793 | ||
794 | kgid = make_kgid(old->user_ns, gid); | |
795 | if (!gid_valid(kgid)) | |
796 | return old_fsgid; | |
d84f4f99 DH |
797 | |
798 | new = prepare_creds(); | |
799 | if (!new) | |
a29c33f4 | 800 | return old_fsgid; |
1da177e4 | 801 | |
a29c33f4 EB |
802 | if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) || |
803 | gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) || | |
c7b96acf | 804 | ns_capable(old->user_ns, CAP_SETGID)) { |
a29c33f4 EB |
805 | if (!gid_eq(kgid, old->fsgid)) { |
806 | new->fsgid = kgid; | |
d84f4f99 | 807 | goto change_okay; |
1da177e4 | 808 | } |
1da177e4 | 809 | } |
d84f4f99 | 810 | |
d84f4f99 DH |
811 | abort_creds(new); |
812 | return old_fsgid; | |
813 | ||
814 | change_okay: | |
815 | commit_creds(new); | |
1da177e4 LT |
816 | return old_fsgid; |
817 | } | |
818 | ||
4a22f166 SR |
819 | /** |
820 | * sys_getpid - return the thread group id of the current process | |
821 | * | |
822 | * Note, despite the name, this returns the tgid not the pid. The tgid and | |
823 | * the pid are identical unless CLONE_THREAD was specified on clone() in | |
824 | * which case the tgid is the same in all threads of the same group. | |
825 | * | |
826 | * This is SMP safe as current->tgid does not change. | |
827 | */ | |
828 | SYSCALL_DEFINE0(getpid) | |
829 | { | |
830 | return task_tgid_vnr(current); | |
831 | } | |
832 | ||
833 | /* Thread ID - the internal kernel "pid" */ | |
834 | SYSCALL_DEFINE0(gettid) | |
835 | { | |
836 | return task_pid_vnr(current); | |
837 | } | |
838 | ||
839 | /* | |
840 | * Accessing ->real_parent is not SMP-safe, it could | |
841 | * change from under us. However, we can use a stale | |
842 | * value of ->real_parent under rcu_read_lock(), see | |
843 | * release_task()->call_rcu(delayed_put_task_struct). | |
844 | */ | |
845 | SYSCALL_DEFINE0(getppid) | |
846 | { | |
847 | int pid; | |
848 | ||
849 | rcu_read_lock(); | |
850 | pid = task_tgid_vnr(rcu_dereference(current->real_parent)); | |
851 | rcu_read_unlock(); | |
852 | ||
853 | return pid; | |
854 | } | |
855 | ||
856 | SYSCALL_DEFINE0(getuid) | |
857 | { | |
858 | /* Only we change this so SMP safe */ | |
859 | return from_kuid_munged(current_user_ns(), current_uid()); | |
860 | } | |
861 | ||
862 | SYSCALL_DEFINE0(geteuid) | |
863 | { | |
864 | /* Only we change this so SMP safe */ | |
865 | return from_kuid_munged(current_user_ns(), current_euid()); | |
866 | } | |
867 | ||
868 | SYSCALL_DEFINE0(getgid) | |
869 | { | |
870 | /* Only we change this so SMP safe */ | |
871 | return from_kgid_munged(current_user_ns(), current_gid()); | |
872 | } | |
873 | ||
874 | SYSCALL_DEFINE0(getegid) | |
875 | { | |
876 | /* Only we change this so SMP safe */ | |
877 | return from_kgid_munged(current_user_ns(), current_egid()); | |
878 | } | |
879 | ||
f06febc9 FM |
880 | void do_sys_times(struct tms *tms) |
881 | { | |
0cf55e1e | 882 | cputime_t tgutime, tgstime, cutime, cstime; |
f06febc9 | 883 | |
e80d0a1a | 884 | thread_group_cputime_adjusted(current, &tgutime, &tgstime); |
f06febc9 FM |
885 | cutime = current->signal->cutime; |
886 | cstime = current->signal->cstime; | |
0cf55e1e HS |
887 | tms->tms_utime = cputime_to_clock_t(tgutime); |
888 | tms->tms_stime = cputime_to_clock_t(tgstime); | |
f06febc9 FM |
889 | tms->tms_cutime = cputime_to_clock_t(cutime); |
890 | tms->tms_cstime = cputime_to_clock_t(cstime); | |
891 | } | |
892 | ||
58fd3aa2 | 893 | SYSCALL_DEFINE1(times, struct tms __user *, tbuf) |
1da177e4 | 894 | { |
1da177e4 LT |
895 | if (tbuf) { |
896 | struct tms tmp; | |
f06febc9 FM |
897 | |
898 | do_sys_times(&tmp); | |
1da177e4 LT |
899 | if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
900 | return -EFAULT; | |
901 | } | |
e3d5a27d | 902 | force_successful_syscall_return(); |
1da177e4 LT |
903 | return (long) jiffies_64_to_clock_t(get_jiffies_64()); |
904 | } | |
905 | ||
906 | /* | |
907 | * This needs some heavy checking ... | |
908 | * I just haven't the stomach for it. I also don't fully | |
909 | * understand sessions/pgrp etc. Let somebody who does explain it. | |
910 | * | |
911 | * OK, I think I have the protection semantics right.... this is really | |
912 | * only important on a multi-user system anyway, to make sure one user | |
913 | * can't send a signal to a process owned by another. -TYT, 12/12/91 | |
914 | * | |
98611e4e | 915 | * !PF_FORKNOEXEC check to conform completely to POSIX. |
1da177e4 | 916 | */ |
b290ebe2 | 917 | SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) |
1da177e4 LT |
918 | { |
919 | struct task_struct *p; | |
ee0acf90 | 920 | struct task_struct *group_leader = current->group_leader; |
4e021306 ON |
921 | struct pid *pgrp; |
922 | int err; | |
1da177e4 LT |
923 | |
924 | if (!pid) | |
b488893a | 925 | pid = task_pid_vnr(group_leader); |
1da177e4 LT |
926 | if (!pgid) |
927 | pgid = pid; | |
928 | if (pgid < 0) | |
929 | return -EINVAL; | |
950eaaca | 930 | rcu_read_lock(); |
1da177e4 LT |
931 | |
932 | /* From this point forward we keep holding onto the tasklist lock | |
933 | * so that our parent does not change from under us. -DaveM | |
934 | */ | |
935 | write_lock_irq(&tasklist_lock); | |
936 | ||
937 | err = -ESRCH; | |
4e021306 | 938 | p = find_task_by_vpid(pid); |
1da177e4 LT |
939 | if (!p) |
940 | goto out; | |
941 | ||
942 | err = -EINVAL; | |
943 | if (!thread_group_leader(p)) | |
944 | goto out; | |
945 | ||
4e021306 | 946 | if (same_thread_group(p->real_parent, group_leader)) { |
1da177e4 | 947 | err = -EPERM; |
41487c65 | 948 | if (task_session(p) != task_session(group_leader)) |
1da177e4 LT |
949 | goto out; |
950 | err = -EACCES; | |
98611e4e | 951 | if (!(p->flags & PF_FORKNOEXEC)) |
1da177e4 LT |
952 | goto out; |
953 | } else { | |
954 | err = -ESRCH; | |
ee0acf90 | 955 | if (p != group_leader) |
1da177e4 LT |
956 | goto out; |
957 | } | |
958 | ||
959 | err = -EPERM; | |
960 | if (p->signal->leader) | |
961 | goto out; | |
962 | ||
4e021306 | 963 | pgrp = task_pid(p); |
1da177e4 | 964 | if (pgid != pid) { |
b488893a | 965 | struct task_struct *g; |
1da177e4 | 966 | |
4e021306 ON |
967 | pgrp = find_vpid(pgid); |
968 | g = pid_task(pgrp, PIDTYPE_PGID); | |
41487c65 | 969 | if (!g || task_session(g) != task_session(group_leader)) |
f020bc46 | 970 | goto out; |
1da177e4 LT |
971 | } |
972 | ||
1da177e4 LT |
973 | err = security_task_setpgid(p, pgid); |
974 | if (err) | |
975 | goto out; | |
976 | ||
1b0f7ffd | 977 | if (task_pgrp(p) != pgrp) |
83beaf3c | 978 | change_pid(p, PIDTYPE_PGID, pgrp); |
1da177e4 LT |
979 | |
980 | err = 0; | |
981 | out: | |
982 | /* All paths lead to here, thus we are safe. -DaveM */ | |
983 | write_unlock_irq(&tasklist_lock); | |
950eaaca | 984 | rcu_read_unlock(); |
1da177e4 LT |
985 | return err; |
986 | } | |
987 | ||
dbf040d9 | 988 | SYSCALL_DEFINE1(getpgid, pid_t, pid) |
1da177e4 | 989 | { |
12a3de0a ON |
990 | struct task_struct *p; |
991 | struct pid *grp; | |
992 | int retval; | |
993 | ||
994 | rcu_read_lock(); | |
756184b7 | 995 | if (!pid) |
12a3de0a | 996 | grp = task_pgrp(current); |
756184b7 | 997 | else { |
1da177e4 | 998 | retval = -ESRCH; |
12a3de0a ON |
999 | p = find_task_by_vpid(pid); |
1000 | if (!p) | |
1001 | goto out; | |
1002 | grp = task_pgrp(p); | |
1003 | if (!grp) | |
1004 | goto out; | |
1005 | ||
1006 | retval = security_task_getpgid(p); | |
1007 | if (retval) | |
1008 | goto out; | |
1da177e4 | 1009 | } |
12a3de0a ON |
1010 | retval = pid_vnr(grp); |
1011 | out: | |
1012 | rcu_read_unlock(); | |
1013 | return retval; | |
1da177e4 LT |
1014 | } |
1015 | ||
1016 | #ifdef __ARCH_WANT_SYS_GETPGRP | |
1017 | ||
dbf040d9 | 1018 | SYSCALL_DEFINE0(getpgrp) |
1da177e4 | 1019 | { |
12a3de0a | 1020 | return sys_getpgid(0); |
1da177e4 LT |
1021 | } |
1022 | ||
1023 | #endif | |
1024 | ||
dbf040d9 | 1025 | SYSCALL_DEFINE1(getsid, pid_t, pid) |
1da177e4 | 1026 | { |
1dd768c0 ON |
1027 | struct task_struct *p; |
1028 | struct pid *sid; | |
1029 | int retval; | |
1030 | ||
1031 | rcu_read_lock(); | |
756184b7 | 1032 | if (!pid) |
1dd768c0 | 1033 | sid = task_session(current); |
756184b7 | 1034 | else { |
1da177e4 | 1035 | retval = -ESRCH; |
1dd768c0 ON |
1036 | p = find_task_by_vpid(pid); |
1037 | if (!p) | |
1038 | goto out; | |
1039 | sid = task_session(p); | |
1040 | if (!sid) | |
1041 | goto out; | |
1042 | ||
1043 | retval = security_task_getsid(p); | |
1044 | if (retval) | |
1045 | goto out; | |
1da177e4 | 1046 | } |
1dd768c0 ON |
1047 | retval = pid_vnr(sid); |
1048 | out: | |
1049 | rcu_read_unlock(); | |
1050 | return retval; | |
1da177e4 LT |
1051 | } |
1052 | ||
81dabb46 ON |
1053 | static void set_special_pids(struct pid *pid) |
1054 | { | |
1055 | struct task_struct *curr = current->group_leader; | |
1056 | ||
1057 | if (task_session(curr) != pid) | |
1058 | change_pid(curr, PIDTYPE_SID, pid); | |
1059 | ||
1060 | if (task_pgrp(curr) != pid) | |
1061 | change_pid(curr, PIDTYPE_PGID, pid); | |
1062 | } | |
1063 | ||
b290ebe2 | 1064 | SYSCALL_DEFINE0(setsid) |
1da177e4 | 1065 | { |
e19f247a | 1066 | struct task_struct *group_leader = current->group_leader; |
e4cc0a9c ON |
1067 | struct pid *sid = task_pid(group_leader); |
1068 | pid_t session = pid_vnr(sid); | |
1da177e4 LT |
1069 | int err = -EPERM; |
1070 | ||
1da177e4 | 1071 | write_lock_irq(&tasklist_lock); |
390e2ff0 EB |
1072 | /* Fail if I am already a session leader */ |
1073 | if (group_leader->signal->leader) | |
1074 | goto out; | |
1075 | ||
430c6231 ON |
1076 | /* Fail if a process group id already exists that equals the |
1077 | * proposed session id. | |
390e2ff0 | 1078 | */ |
6806aac6 | 1079 | if (pid_task(sid, PIDTYPE_PGID)) |
1da177e4 LT |
1080 | goto out; |
1081 | ||
e19f247a | 1082 | group_leader->signal->leader = 1; |
81dabb46 | 1083 | set_special_pids(sid); |
24ec839c | 1084 | |
9c9f4ded | 1085 | proc_clear_tty(group_leader); |
24ec839c | 1086 | |
e4cc0a9c | 1087 | err = session; |
1da177e4 LT |
1088 | out: |
1089 | write_unlock_irq(&tasklist_lock); | |
5091faa4 | 1090 | if (err > 0) { |
0d0df599 | 1091 | proc_sid_connector(group_leader); |
5091faa4 MG |
1092 | sched_autogroup_create_attach(group_leader); |
1093 | } | |
1da177e4 LT |
1094 | return err; |
1095 | } | |
1096 | ||
1da177e4 LT |
1097 | DECLARE_RWSEM(uts_sem); |
1098 | ||
e28cbf22 CH |
1099 | #ifdef COMPAT_UTS_MACHINE |
1100 | #define override_architecture(name) \ | |
46da2766 | 1101 | (personality(current->personality) == PER_LINUX32 && \ |
e28cbf22 CH |
1102 | copy_to_user(name->machine, COMPAT_UTS_MACHINE, \ |
1103 | sizeof(COMPAT_UTS_MACHINE))) | |
1104 | #else | |
1105 | #define override_architecture(name) 0 | |
1106 | #endif | |
1107 | ||
be27425d AK |
1108 | /* |
1109 | * Work around broken programs that cannot handle "Linux 3.0". | |
1110 | * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40 | |
39afb5ee | 1111 | * And we map 4.x to 2.6.60+x, so 4.0 would be 2.6.60. |
be27425d | 1112 | */ |
2702b152 | 1113 | static int override_release(char __user *release, size_t len) |
be27425d AK |
1114 | { |
1115 | int ret = 0; | |
be27425d AK |
1116 | |
1117 | if (current->personality & UNAME26) { | |
2702b152 KC |
1118 | const char *rest = UTS_RELEASE; |
1119 | char buf[65] = { 0 }; | |
be27425d AK |
1120 | int ndots = 0; |
1121 | unsigned v; | |
2702b152 | 1122 | size_t copy; |
be27425d AK |
1123 | |
1124 | while (*rest) { | |
1125 | if (*rest == '.' && ++ndots >= 3) | |
1126 | break; | |
1127 | if (!isdigit(*rest) && *rest != '.') | |
1128 | break; | |
1129 | rest++; | |
1130 | } | |
39afb5ee | 1131 | v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 60; |
31fd84b9 | 1132 | copy = clamp_t(size_t, len, 1, sizeof(buf)); |
2702b152 KC |
1133 | copy = scnprintf(buf, copy, "2.6.%u%s", v, rest); |
1134 | ret = copy_to_user(release, buf, copy + 1); | |
be27425d AK |
1135 | } |
1136 | return ret; | |
1137 | } | |
1138 | ||
e48fbb69 | 1139 | SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name) |
1da177e4 LT |
1140 | { |
1141 | int errno = 0; | |
1142 | ||
1143 | down_read(&uts_sem); | |
e9ff3990 | 1144 | if (copy_to_user(name, utsname(), sizeof *name)) |
1da177e4 LT |
1145 | errno = -EFAULT; |
1146 | up_read(&uts_sem); | |
e28cbf22 | 1147 | |
be27425d AK |
1148 | if (!errno && override_release(name->release, sizeof(name->release))) |
1149 | errno = -EFAULT; | |
e28cbf22 CH |
1150 | if (!errno && override_architecture(name)) |
1151 | errno = -EFAULT; | |
1da177e4 LT |
1152 | return errno; |
1153 | } | |
1154 | ||
5cacdb4a CH |
1155 | #ifdef __ARCH_WANT_SYS_OLD_UNAME |
1156 | /* | |
1157 | * Old cruft | |
1158 | */ | |
1159 | SYSCALL_DEFINE1(uname, struct old_utsname __user *, name) | |
1160 | { | |
1161 | int error = 0; | |
1162 | ||
1163 | if (!name) | |
1164 | return -EFAULT; | |
1165 | ||
1166 | down_read(&uts_sem); | |
1167 | if (copy_to_user(name, utsname(), sizeof(*name))) | |
1168 | error = -EFAULT; | |
1169 | up_read(&uts_sem); | |
1170 | ||
be27425d AK |
1171 | if (!error && override_release(name->release, sizeof(name->release))) |
1172 | error = -EFAULT; | |
5cacdb4a CH |
1173 | if (!error && override_architecture(name)) |
1174 | error = -EFAULT; | |
1175 | return error; | |
1176 | } | |
1177 | ||
1178 | SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name) | |
1179 | { | |
1180 | int error; | |
1181 | ||
1182 | if (!name) | |
1183 | return -EFAULT; | |
1184 | if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname))) | |
1185 | return -EFAULT; | |
1186 | ||
1187 | down_read(&uts_sem); | |
1188 | error = __copy_to_user(&name->sysname, &utsname()->sysname, | |
1189 | __OLD_UTS_LEN); | |
1190 | error |= __put_user(0, name->sysname + __OLD_UTS_LEN); | |
1191 | error |= __copy_to_user(&name->nodename, &utsname()->nodename, | |
1192 | __OLD_UTS_LEN); | |
1193 | error |= __put_user(0, name->nodename + __OLD_UTS_LEN); | |
1194 | error |= __copy_to_user(&name->release, &utsname()->release, | |
1195 | __OLD_UTS_LEN); | |
1196 | error |= __put_user(0, name->release + __OLD_UTS_LEN); | |
1197 | error |= __copy_to_user(&name->version, &utsname()->version, | |
1198 | __OLD_UTS_LEN); | |
1199 | error |= __put_user(0, name->version + __OLD_UTS_LEN); | |
1200 | error |= __copy_to_user(&name->machine, &utsname()->machine, | |
1201 | __OLD_UTS_LEN); | |
1202 | error |= __put_user(0, name->machine + __OLD_UTS_LEN); | |
1203 | up_read(&uts_sem); | |
1204 | ||
1205 | if (!error && override_architecture(name)) | |
1206 | error = -EFAULT; | |
be27425d AK |
1207 | if (!error && override_release(name->release, sizeof(name->release))) |
1208 | error = -EFAULT; | |
5cacdb4a CH |
1209 | return error ? -EFAULT : 0; |
1210 | } | |
1211 | #endif | |
1212 | ||
5a8a82b1 | 1213 | SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) |
1da177e4 LT |
1214 | { |
1215 | int errno; | |
1216 | char tmp[__NEW_UTS_LEN]; | |
1217 | ||
bb96a6f5 | 1218 | if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
1da177e4 | 1219 | return -EPERM; |
fc832ad3 | 1220 | |
1da177e4 LT |
1221 | if (len < 0 || len > __NEW_UTS_LEN) |
1222 | return -EINVAL; | |
1223 | down_write(&uts_sem); | |
1224 | errno = -EFAULT; | |
1225 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1226 | struct new_utsname *u = utsname(); |
1227 | ||
1228 | memcpy(u->nodename, tmp, len); | |
1229 | memset(u->nodename + len, 0, sizeof(u->nodename) - len); | |
1da177e4 | 1230 | errno = 0; |
499eea6b | 1231 | uts_proc_notify(UTS_PROC_HOSTNAME); |
1da177e4 LT |
1232 | } |
1233 | up_write(&uts_sem); | |
1234 | return errno; | |
1235 | } | |
1236 | ||
1237 | #ifdef __ARCH_WANT_SYS_GETHOSTNAME | |
1238 | ||
5a8a82b1 | 1239 | SYSCALL_DEFINE2(gethostname, char __user *, name, int, len) |
1da177e4 LT |
1240 | { |
1241 | int i, errno; | |
9679e4dd | 1242 | struct new_utsname *u; |
1da177e4 LT |
1243 | |
1244 | if (len < 0) | |
1245 | return -EINVAL; | |
1246 | down_read(&uts_sem); | |
9679e4dd AM |
1247 | u = utsname(); |
1248 | i = 1 + strlen(u->nodename); | |
1da177e4 LT |
1249 | if (i > len) |
1250 | i = len; | |
1251 | errno = 0; | |
9679e4dd | 1252 | if (copy_to_user(name, u->nodename, i)) |
1da177e4 LT |
1253 | errno = -EFAULT; |
1254 | up_read(&uts_sem); | |
1255 | return errno; | |
1256 | } | |
1257 | ||
1258 | #endif | |
1259 | ||
1260 | /* | |
1261 | * Only setdomainname; getdomainname can be implemented by calling | |
1262 | * uname() | |
1263 | */ | |
5a8a82b1 | 1264 | SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) |
1da177e4 LT |
1265 | { |
1266 | int errno; | |
1267 | char tmp[__NEW_UTS_LEN]; | |
1268 | ||
fc832ad3 | 1269 | if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
1da177e4 LT |
1270 | return -EPERM; |
1271 | if (len < 0 || len > __NEW_UTS_LEN) | |
1272 | return -EINVAL; | |
1273 | ||
1274 | down_write(&uts_sem); | |
1275 | errno = -EFAULT; | |
1276 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1277 | struct new_utsname *u = utsname(); |
1278 | ||
1279 | memcpy(u->domainname, tmp, len); | |
1280 | memset(u->domainname + len, 0, sizeof(u->domainname) - len); | |
1da177e4 | 1281 | errno = 0; |
499eea6b | 1282 | uts_proc_notify(UTS_PROC_DOMAINNAME); |
1da177e4 LT |
1283 | } |
1284 | up_write(&uts_sem); | |
1285 | return errno; | |
1286 | } | |
1287 | ||
e48fbb69 | 1288 | SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1da177e4 | 1289 | { |
b9518345 JS |
1290 | struct rlimit value; |
1291 | int ret; | |
1292 | ||
1293 | ret = do_prlimit(current, resource, NULL, &value); | |
1294 | if (!ret) | |
1295 | ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; | |
1296 | ||
1297 | return ret; | |
1da177e4 LT |
1298 | } |
1299 | ||
1300 | #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT | |
1301 | ||
1302 | /* | |
1303 | * Back compatibility for getrlimit. Needed for some apps. | |
1304 | */ | |
e48fbb69 HC |
1305 | SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, |
1306 | struct rlimit __user *, rlim) | |
1da177e4 LT |
1307 | { |
1308 | struct rlimit x; | |
1309 | if (resource >= RLIM_NLIMITS) | |
1310 | return -EINVAL; | |
1311 | ||
1312 | task_lock(current->group_leader); | |
1313 | x = current->signal->rlim[resource]; | |
1314 | task_unlock(current->group_leader); | |
756184b7 | 1315 | if (x.rlim_cur > 0x7FFFFFFF) |
1da177e4 | 1316 | x.rlim_cur = 0x7FFFFFFF; |
756184b7 | 1317 | if (x.rlim_max > 0x7FFFFFFF) |
1da177e4 | 1318 | x.rlim_max = 0x7FFFFFFF; |
ec94fc3d | 1319 | return copy_to_user(rlim, &x, sizeof(x)) ? -EFAULT : 0; |
1da177e4 LT |
1320 | } |
1321 | ||
1322 | #endif | |
1323 | ||
c022a0ac JS |
1324 | static inline bool rlim64_is_infinity(__u64 rlim64) |
1325 | { | |
1326 | #if BITS_PER_LONG < 64 | |
1327 | return rlim64 >= ULONG_MAX; | |
1328 | #else | |
1329 | return rlim64 == RLIM64_INFINITY; | |
1330 | #endif | |
1331 | } | |
1332 | ||
1333 | static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64) | |
1334 | { | |
1335 | if (rlim->rlim_cur == RLIM_INFINITY) | |
1336 | rlim64->rlim_cur = RLIM64_INFINITY; | |
1337 | else | |
1338 | rlim64->rlim_cur = rlim->rlim_cur; | |
1339 | if (rlim->rlim_max == RLIM_INFINITY) | |
1340 | rlim64->rlim_max = RLIM64_INFINITY; | |
1341 | else | |
1342 | rlim64->rlim_max = rlim->rlim_max; | |
1343 | } | |
1344 | ||
1345 | static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim) | |
1346 | { | |
1347 | if (rlim64_is_infinity(rlim64->rlim_cur)) | |
1348 | rlim->rlim_cur = RLIM_INFINITY; | |
1349 | else | |
1350 | rlim->rlim_cur = (unsigned long)rlim64->rlim_cur; | |
1351 | if (rlim64_is_infinity(rlim64->rlim_max)) | |
1352 | rlim->rlim_max = RLIM_INFINITY; | |
1353 | else | |
1354 | rlim->rlim_max = (unsigned long)rlim64->rlim_max; | |
1355 | } | |
1356 | ||
1c1e618d | 1357 | /* make sure you are allowed to change @tsk limits before calling this */ |
5b41535a JS |
1358 | int do_prlimit(struct task_struct *tsk, unsigned int resource, |
1359 | struct rlimit *new_rlim, struct rlimit *old_rlim) | |
1da177e4 | 1360 | { |
5b41535a | 1361 | struct rlimit *rlim; |
86f162f4 | 1362 | int retval = 0; |
1da177e4 LT |
1363 | |
1364 | if (resource >= RLIM_NLIMITS) | |
1365 | return -EINVAL; | |
5b41535a JS |
1366 | if (new_rlim) { |
1367 | if (new_rlim->rlim_cur > new_rlim->rlim_max) | |
1368 | return -EINVAL; | |
1369 | if (resource == RLIMIT_NOFILE && | |
1370 | new_rlim->rlim_max > sysctl_nr_open) | |
1371 | return -EPERM; | |
1372 | } | |
1da177e4 | 1373 | |
1c1e618d JS |
1374 | /* protect tsk->signal and tsk->sighand from disappearing */ |
1375 | read_lock(&tasklist_lock); | |
1376 | if (!tsk->sighand) { | |
1377 | retval = -ESRCH; | |
1378 | goto out; | |
1379 | } | |
1380 | ||
5b41535a | 1381 | rlim = tsk->signal->rlim + resource; |
86f162f4 | 1382 | task_lock(tsk->group_leader); |
5b41535a | 1383 | if (new_rlim) { |
fc832ad3 SH |
1384 | /* Keep the capable check against init_user_ns until |
1385 | cgroups can contain all limits */ | |
5b41535a JS |
1386 | if (new_rlim->rlim_max > rlim->rlim_max && |
1387 | !capable(CAP_SYS_RESOURCE)) | |
1388 | retval = -EPERM; | |
1389 | if (!retval) | |
1390 | retval = security_task_setrlimit(tsk->group_leader, | |
1391 | resource, new_rlim); | |
1392 | if (resource == RLIMIT_CPU && new_rlim->rlim_cur == 0) { | |
1393 | /* | |
1394 | * The caller is asking for an immediate RLIMIT_CPU | |
1395 | * expiry. But we use the zero value to mean "it was | |
1396 | * never set". So let's cheat and make it one second | |
1397 | * instead | |
1398 | */ | |
1399 | new_rlim->rlim_cur = 1; | |
1400 | } | |
1401 | } | |
1402 | if (!retval) { | |
1403 | if (old_rlim) | |
1404 | *old_rlim = *rlim; | |
1405 | if (new_rlim) | |
1406 | *rlim = *new_rlim; | |
9926e4c7 | 1407 | } |
7855c35d | 1408 | task_unlock(tsk->group_leader); |
1da177e4 | 1409 | |
d3561f78 AM |
1410 | /* |
1411 | * RLIMIT_CPU handling. Note that the kernel fails to return an error | |
1412 | * code if it rejected the user's attempt to set RLIMIT_CPU. This is a | |
1413 | * very long-standing error, and fixing it now risks breakage of | |
1414 | * applications, so we live with it | |
1415 | */ | |
5b41535a JS |
1416 | if (!retval && new_rlim && resource == RLIMIT_CPU && |
1417 | new_rlim->rlim_cur != RLIM_INFINITY) | |
1418 | update_rlimit_cpu(tsk, new_rlim->rlim_cur); | |
ec9e16ba | 1419 | out: |
1c1e618d | 1420 | read_unlock(&tasklist_lock); |
2fb9d268 | 1421 | return retval; |
1da177e4 LT |
1422 | } |
1423 | ||
c022a0ac JS |
1424 | /* rcu lock must be held */ |
1425 | static int check_prlimit_permission(struct task_struct *task) | |
1426 | { | |
1427 | const struct cred *cred = current_cred(), *tcred; | |
1428 | ||
fc832ad3 SH |
1429 | if (current == task) |
1430 | return 0; | |
c022a0ac | 1431 | |
fc832ad3 | 1432 | tcred = __task_cred(task); |
5af66203 EB |
1433 | if (uid_eq(cred->uid, tcred->euid) && |
1434 | uid_eq(cred->uid, tcred->suid) && | |
1435 | uid_eq(cred->uid, tcred->uid) && | |
1436 | gid_eq(cred->gid, tcred->egid) && | |
1437 | gid_eq(cred->gid, tcred->sgid) && | |
1438 | gid_eq(cred->gid, tcred->gid)) | |
fc832ad3 | 1439 | return 0; |
c4a4d603 | 1440 | if (ns_capable(tcred->user_ns, CAP_SYS_RESOURCE)) |
fc832ad3 SH |
1441 | return 0; |
1442 | ||
1443 | return -EPERM; | |
c022a0ac JS |
1444 | } |
1445 | ||
1446 | SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource, | |
1447 | const struct rlimit64 __user *, new_rlim, | |
1448 | struct rlimit64 __user *, old_rlim) | |
1449 | { | |
1450 | struct rlimit64 old64, new64; | |
1451 | struct rlimit old, new; | |
1452 | struct task_struct *tsk; | |
1453 | int ret; | |
1454 | ||
1455 | if (new_rlim) { | |
1456 | if (copy_from_user(&new64, new_rlim, sizeof(new64))) | |
1457 | return -EFAULT; | |
1458 | rlim64_to_rlim(&new64, &new); | |
1459 | } | |
1460 | ||
1461 | rcu_read_lock(); | |
1462 | tsk = pid ? find_task_by_vpid(pid) : current; | |
1463 | if (!tsk) { | |
1464 | rcu_read_unlock(); | |
1465 | return -ESRCH; | |
1466 | } | |
1467 | ret = check_prlimit_permission(tsk); | |
1468 | if (ret) { | |
1469 | rcu_read_unlock(); | |
1470 | return ret; | |
1471 | } | |
1472 | get_task_struct(tsk); | |
1473 | rcu_read_unlock(); | |
1474 | ||
1475 | ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL, | |
1476 | old_rlim ? &old : NULL); | |
1477 | ||
1478 | if (!ret && old_rlim) { | |
1479 | rlim_to_rlim64(&old, &old64); | |
1480 | if (copy_to_user(old_rlim, &old64, sizeof(old64))) | |
1481 | ret = -EFAULT; | |
1482 | } | |
1483 | ||
1484 | put_task_struct(tsk); | |
1485 | return ret; | |
1486 | } | |
1487 | ||
7855c35d JS |
1488 | SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1489 | { | |
1490 | struct rlimit new_rlim; | |
1491 | ||
1492 | if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) | |
1493 | return -EFAULT; | |
5b41535a | 1494 | return do_prlimit(current, resource, &new_rlim, NULL); |
7855c35d JS |
1495 | } |
1496 | ||
1da177e4 LT |
1497 | /* |
1498 | * It would make sense to put struct rusage in the task_struct, | |
1499 | * except that would make the task_struct be *really big*. After | |
1500 | * task_struct gets moved into malloc'ed memory, it would | |
1501 | * make sense to do this. It will make moving the rest of the information | |
1502 | * a lot simpler! (Which we're not doing right now because we're not | |
1503 | * measuring them yet). | |
1504 | * | |
1da177e4 LT |
1505 | * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
1506 | * races with threads incrementing their own counters. But since word | |
1507 | * reads are atomic, we either get new values or old values and we don't | |
1508 | * care which for the sums. We always take the siglock to protect reading | |
1509 | * the c* fields from p->signal from races with exit.c updating those | |
1510 | * fields when reaping, so a sample either gets all the additions of a | |
1511 | * given child after it's reaped, or none so this sample is before reaping. | |
2dd0ebcd | 1512 | * |
de047c1b RT |
1513 | * Locking: |
1514 | * We need to take the siglock for CHILDEREN, SELF and BOTH | |
1515 | * for the cases current multithreaded, non-current single threaded | |
1516 | * non-current multithreaded. Thread traversal is now safe with | |
1517 | * the siglock held. | |
1518 | * Strictly speaking, we donot need to take the siglock if we are current and | |
1519 | * single threaded, as no one else can take our signal_struct away, no one | |
1520 | * else can reap the children to update signal->c* counters, and no one else | |
1521 | * can race with the signal-> fields. If we do not take any lock, the | |
1522 | * signal-> fields could be read out of order while another thread was just | |
1523 | * exiting. So we should place a read memory barrier when we avoid the lock. | |
1524 | * On the writer side, write memory barrier is implied in __exit_signal | |
1525 | * as __exit_signal releases the siglock spinlock after updating the signal-> | |
1526 | * fields. But we don't do this yet to keep things simple. | |
2dd0ebcd | 1527 | * |
1da177e4 LT |
1528 | */ |
1529 | ||
f06febc9 | 1530 | static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) |
679c9cd4 | 1531 | { |
679c9cd4 SK |
1532 | r->ru_nvcsw += t->nvcsw; |
1533 | r->ru_nivcsw += t->nivcsw; | |
1534 | r->ru_minflt += t->min_flt; | |
1535 | r->ru_majflt += t->maj_flt; | |
1536 | r->ru_inblock += task_io_get_inblock(t); | |
1537 | r->ru_oublock += task_io_get_oublock(t); | |
1538 | } | |
1539 | ||
1da177e4 LT |
1540 | static void k_getrusage(struct task_struct *p, int who, struct rusage *r) |
1541 | { | |
1542 | struct task_struct *t; | |
1543 | unsigned long flags; | |
0cf55e1e | 1544 | cputime_t tgutime, tgstime, utime, stime; |
1f10206c | 1545 | unsigned long maxrss = 0; |
1da177e4 | 1546 | |
ec94fc3d | 1547 | memset((char *)r, 0, sizeof (*r)); |
64861634 | 1548 | utime = stime = 0; |
1da177e4 | 1549 | |
679c9cd4 | 1550 | if (who == RUSAGE_THREAD) { |
e80d0a1a | 1551 | task_cputime_adjusted(current, &utime, &stime); |
f06febc9 | 1552 | accumulate_thread_rusage(p, r); |
1f10206c | 1553 | maxrss = p->signal->maxrss; |
679c9cd4 SK |
1554 | goto out; |
1555 | } | |
1556 | ||
d6cf723a | 1557 | if (!lock_task_sighand(p, &flags)) |
de047c1b | 1558 | return; |
0f59cc4a | 1559 | |
1da177e4 | 1560 | switch (who) { |
ec94fc3d | 1561 | case RUSAGE_BOTH: |
1562 | case RUSAGE_CHILDREN: | |
1563 | utime = p->signal->cutime; | |
1564 | stime = p->signal->cstime; | |
1565 | r->ru_nvcsw = p->signal->cnvcsw; | |
1566 | r->ru_nivcsw = p->signal->cnivcsw; | |
1567 | r->ru_minflt = p->signal->cmin_flt; | |
1568 | r->ru_majflt = p->signal->cmaj_flt; | |
1569 | r->ru_inblock = p->signal->cinblock; | |
1570 | r->ru_oublock = p->signal->coublock; | |
1571 | maxrss = p->signal->cmaxrss; | |
1572 | ||
1573 | if (who == RUSAGE_CHILDREN) | |
1da177e4 | 1574 | break; |
0f59cc4a | 1575 | |
ec94fc3d | 1576 | case RUSAGE_SELF: |
1577 | thread_group_cputime_adjusted(p, &tgutime, &tgstime); | |
1578 | utime += tgutime; | |
1579 | stime += tgstime; | |
1580 | r->ru_nvcsw += p->signal->nvcsw; | |
1581 | r->ru_nivcsw += p->signal->nivcsw; | |
1582 | r->ru_minflt += p->signal->min_flt; | |
1583 | r->ru_majflt += p->signal->maj_flt; | |
1584 | r->ru_inblock += p->signal->inblock; | |
1585 | r->ru_oublock += p->signal->oublock; | |
1586 | if (maxrss < p->signal->maxrss) | |
1587 | maxrss = p->signal->maxrss; | |
1588 | t = p; | |
1589 | do { | |
1590 | accumulate_thread_rusage(t, r); | |
1591 | } while_each_thread(p, t); | |
1592 | break; | |
1593 | ||
1594 | default: | |
1595 | BUG(); | |
1da177e4 | 1596 | } |
de047c1b | 1597 | unlock_task_sighand(p, &flags); |
de047c1b | 1598 | |
679c9cd4 | 1599 | out: |
0f59cc4a ON |
1600 | cputime_to_timeval(utime, &r->ru_utime); |
1601 | cputime_to_timeval(stime, &r->ru_stime); | |
1f10206c JP |
1602 | |
1603 | if (who != RUSAGE_CHILDREN) { | |
1604 | struct mm_struct *mm = get_task_mm(p); | |
ec94fc3d | 1605 | |
1f10206c JP |
1606 | if (mm) { |
1607 | setmax_mm_hiwater_rss(&maxrss, mm); | |
1608 | mmput(mm); | |
1609 | } | |
1610 | } | |
1611 | r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */ | |
1da177e4 LT |
1612 | } |
1613 | ||
1614 | int getrusage(struct task_struct *p, int who, struct rusage __user *ru) | |
1615 | { | |
1616 | struct rusage r; | |
ec94fc3d | 1617 | |
1da177e4 | 1618 | k_getrusage(p, who, &r); |
1da177e4 LT |
1619 | return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
1620 | } | |
1621 | ||
e48fbb69 | 1622 | SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) |
1da177e4 | 1623 | { |
679c9cd4 SK |
1624 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
1625 | who != RUSAGE_THREAD) | |
1da177e4 LT |
1626 | return -EINVAL; |
1627 | return getrusage(current, who, ru); | |
1628 | } | |
1629 | ||
8d2d5c4a AV |
1630 | #ifdef CONFIG_COMPAT |
1631 | COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru) | |
1632 | { | |
1633 | struct rusage r; | |
1634 | ||
1635 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && | |
1636 | who != RUSAGE_THREAD) | |
1637 | return -EINVAL; | |
1638 | ||
1639 | k_getrusage(current, who, &r); | |
1640 | return put_compat_rusage(&r, ru); | |
1641 | } | |
1642 | #endif | |
1643 | ||
e48fbb69 | 1644 | SYSCALL_DEFINE1(umask, int, mask) |
1da177e4 LT |
1645 | { |
1646 | mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); | |
1647 | return mask; | |
1648 | } | |
3b7391de | 1649 | |
71fe97e1 | 1650 | static int prctl_set_mm_exe_file_locked(struct mm_struct *mm, unsigned int fd) |
b32dfe37 | 1651 | { |
2903ff01 | 1652 | struct fd exe; |
496ad9aa | 1653 | struct inode *inode; |
2903ff01 | 1654 | int err; |
b32dfe37 | 1655 | |
96dad67f | 1656 | VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_sem), mm); |
71fe97e1 | 1657 | |
2903ff01 AV |
1658 | exe = fdget(fd); |
1659 | if (!exe.file) | |
b32dfe37 CG |
1660 | return -EBADF; |
1661 | ||
496ad9aa | 1662 | inode = file_inode(exe.file); |
b32dfe37 CG |
1663 | |
1664 | /* | |
1665 | * Because the original mm->exe_file points to executable file, make | |
1666 | * sure that this one is executable as well, to avoid breaking an | |
1667 | * overall picture. | |
1668 | */ | |
1669 | err = -EACCES; | |
496ad9aa | 1670 | if (!S_ISREG(inode->i_mode) || |
2903ff01 | 1671 | exe.file->f_path.mnt->mnt_flags & MNT_NOEXEC) |
b32dfe37 CG |
1672 | goto exit; |
1673 | ||
496ad9aa | 1674 | err = inode_permission(inode, MAY_EXEC); |
b32dfe37 CG |
1675 | if (err) |
1676 | goto exit; | |
1677 | ||
bafb282d | 1678 | /* |
4229fb1d | 1679 | * Forbid mm->exe_file change if old file still mapped. |
bafb282d KK |
1680 | */ |
1681 | err = -EBUSY; | |
4229fb1d KK |
1682 | if (mm->exe_file) { |
1683 | struct vm_area_struct *vma; | |
1684 | ||
1685 | for (vma = mm->mmap; vma; vma = vma->vm_next) | |
1686 | if (vma->vm_file && | |
1687 | path_equal(&vma->vm_file->f_path, | |
1688 | &mm->exe_file->f_path)) | |
71fe97e1 | 1689 | goto exit; |
bafb282d KK |
1690 | } |
1691 | ||
b32dfe37 CG |
1692 | /* |
1693 | * The symlink can be changed only once, just to disallow arbitrary | |
1694 | * transitions malicious software might bring in. This means one | |
1695 | * could make a snapshot over all processes running and monitor | |
1696 | * /proc/pid/exe changes to notice unusual activity if needed. | |
1697 | */ | |
bafb282d KK |
1698 | err = -EPERM; |
1699 | if (test_and_set_bit(MMF_EXE_FILE_CHANGED, &mm->flags)) | |
71fe97e1 | 1700 | goto exit; |
bafb282d | 1701 | |
4229fb1d | 1702 | err = 0; |
2903ff01 | 1703 | set_mm_exe_file(mm, exe.file); /* this grabs a reference to exe.file */ |
b32dfe37 | 1704 | exit: |
2903ff01 | 1705 | fdput(exe); |
b32dfe37 CG |
1706 | return err; |
1707 | } | |
1708 | ||
f606b77f CG |
1709 | #ifdef CONFIG_CHECKPOINT_RESTORE |
1710 | /* | |
1711 | * WARNING: we don't require any capability here so be very careful | |
1712 | * in what is allowed for modification from userspace. | |
1713 | */ | |
1714 | static int validate_prctl_map(struct prctl_mm_map *prctl_map) | |
1715 | { | |
1716 | unsigned long mmap_max_addr = TASK_SIZE; | |
1717 | struct mm_struct *mm = current->mm; | |
1718 | int error = -EINVAL, i; | |
1719 | ||
1720 | static const unsigned char offsets[] = { | |
1721 | offsetof(struct prctl_mm_map, start_code), | |
1722 | offsetof(struct prctl_mm_map, end_code), | |
1723 | offsetof(struct prctl_mm_map, start_data), | |
1724 | offsetof(struct prctl_mm_map, end_data), | |
1725 | offsetof(struct prctl_mm_map, start_brk), | |
1726 | offsetof(struct prctl_mm_map, brk), | |
1727 | offsetof(struct prctl_mm_map, start_stack), | |
1728 | offsetof(struct prctl_mm_map, arg_start), | |
1729 | offsetof(struct prctl_mm_map, arg_end), | |
1730 | offsetof(struct prctl_mm_map, env_start), | |
1731 | offsetof(struct prctl_mm_map, env_end), | |
1732 | }; | |
1733 | ||
1734 | /* | |
1735 | * Make sure the members are not somewhere outside | |
1736 | * of allowed address space. | |
1737 | */ | |
1738 | for (i = 0; i < ARRAY_SIZE(offsets); i++) { | |
1739 | u64 val = *(u64 *)((char *)prctl_map + offsets[i]); | |
1740 | ||
1741 | if ((unsigned long)val >= mmap_max_addr || | |
1742 | (unsigned long)val < mmap_min_addr) | |
1743 | goto out; | |
1744 | } | |
1745 | ||
1746 | /* | |
1747 | * Make sure the pairs are ordered. | |
1748 | */ | |
1749 | #define __prctl_check_order(__m1, __op, __m2) \ | |
1750 | ((unsigned long)prctl_map->__m1 __op \ | |
1751 | (unsigned long)prctl_map->__m2) ? 0 : -EINVAL | |
1752 | error = __prctl_check_order(start_code, <, end_code); | |
1753 | error |= __prctl_check_order(start_data, <, end_data); | |
1754 | error |= __prctl_check_order(start_brk, <=, brk); | |
1755 | error |= __prctl_check_order(arg_start, <=, arg_end); | |
1756 | error |= __prctl_check_order(env_start, <=, env_end); | |
1757 | if (error) | |
1758 | goto out; | |
1759 | #undef __prctl_check_order | |
1760 | ||
1761 | error = -EINVAL; | |
1762 | ||
1763 | /* | |
1764 | * @brk should be after @end_data in traditional maps. | |
1765 | */ | |
1766 | if (prctl_map->start_brk <= prctl_map->end_data || | |
1767 | prctl_map->brk <= prctl_map->end_data) | |
1768 | goto out; | |
1769 | ||
1770 | /* | |
1771 | * Neither we should allow to override limits if they set. | |
1772 | */ | |
1773 | if (check_data_rlimit(rlimit(RLIMIT_DATA), prctl_map->brk, | |
1774 | prctl_map->start_brk, prctl_map->end_data, | |
1775 | prctl_map->start_data)) | |
1776 | goto out; | |
1777 | ||
1778 | /* | |
1779 | * Someone is trying to cheat the auxv vector. | |
1780 | */ | |
1781 | if (prctl_map->auxv_size) { | |
1782 | if (!prctl_map->auxv || prctl_map->auxv_size > sizeof(mm->saved_auxv)) | |
1783 | goto out; | |
1784 | } | |
1785 | ||
1786 | /* | |
1787 | * Finally, make sure the caller has the rights to | |
1788 | * change /proc/pid/exe link: only local root should | |
1789 | * be allowed to. | |
1790 | */ | |
1791 | if (prctl_map->exe_fd != (u32)-1) { | |
1792 | struct user_namespace *ns = current_user_ns(); | |
1793 | const struct cred *cred = current_cred(); | |
1794 | ||
1795 | if (!uid_eq(cred->uid, make_kuid(ns, 0)) || | |
1796 | !gid_eq(cred->gid, make_kgid(ns, 0))) | |
1797 | goto out; | |
1798 | } | |
1799 | ||
1800 | error = 0; | |
1801 | out: | |
1802 | return error; | |
1803 | } | |
1804 | ||
1805 | static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size) | |
1806 | { | |
1807 | struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, }; | |
1808 | unsigned long user_auxv[AT_VECTOR_SIZE]; | |
1809 | struct mm_struct *mm = current->mm; | |
1810 | int error; | |
1811 | ||
1812 | BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); | |
1813 | BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256); | |
1814 | ||
1815 | if (opt == PR_SET_MM_MAP_SIZE) | |
1816 | return put_user((unsigned int)sizeof(prctl_map), | |
1817 | (unsigned int __user *)addr); | |
1818 | ||
1819 | if (data_size != sizeof(prctl_map)) | |
1820 | return -EINVAL; | |
1821 | ||
1822 | if (copy_from_user(&prctl_map, addr, sizeof(prctl_map))) | |
1823 | return -EFAULT; | |
1824 | ||
1825 | error = validate_prctl_map(&prctl_map); | |
1826 | if (error) | |
1827 | return error; | |
1828 | ||
1829 | if (prctl_map.auxv_size) { | |
1830 | memset(user_auxv, 0, sizeof(user_auxv)); | |
1831 | if (copy_from_user(user_auxv, | |
1832 | (const void __user *)prctl_map.auxv, | |
1833 | prctl_map.auxv_size)) | |
1834 | return -EFAULT; | |
1835 | ||
1836 | /* Last entry must be AT_NULL as specification requires */ | |
1837 | user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL; | |
1838 | user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL; | |
1839 | } | |
1840 | ||
1841 | down_write(&mm->mmap_sem); | |
1842 | if (prctl_map.exe_fd != (u32)-1) | |
1843 | error = prctl_set_mm_exe_file_locked(mm, prctl_map.exe_fd); | |
1844 | downgrade_write(&mm->mmap_sem); | |
1845 | if (error) | |
1846 | goto out; | |
1847 | ||
1848 | /* | |
1849 | * We don't validate if these members are pointing to | |
1850 | * real present VMAs because application may have correspond | |
1851 | * VMAs already unmapped and kernel uses these members for statistics | |
1852 | * output in procfs mostly, except | |
1853 | * | |
1854 | * - @start_brk/@brk which are used in do_brk but kernel lookups | |
1855 | * for VMAs when updating these memvers so anything wrong written | |
1856 | * here cause kernel to swear at userspace program but won't lead | |
1857 | * to any problem in kernel itself | |
1858 | */ | |
1859 | ||
1860 | mm->start_code = prctl_map.start_code; | |
1861 | mm->end_code = prctl_map.end_code; | |
1862 | mm->start_data = prctl_map.start_data; | |
1863 | mm->end_data = prctl_map.end_data; | |
1864 | mm->start_brk = prctl_map.start_brk; | |
1865 | mm->brk = prctl_map.brk; | |
1866 | mm->start_stack = prctl_map.start_stack; | |
1867 | mm->arg_start = prctl_map.arg_start; | |
1868 | mm->arg_end = prctl_map.arg_end; | |
1869 | mm->env_start = prctl_map.env_start; | |
1870 | mm->env_end = prctl_map.env_end; | |
1871 | ||
1872 | /* | |
1873 | * Note this update of @saved_auxv is lockless thus | |
1874 | * if someone reads this member in procfs while we're | |
1875 | * updating -- it may get partly updated results. It's | |
1876 | * known and acceptable trade off: we leave it as is to | |
1877 | * not introduce additional locks here making the kernel | |
1878 | * more complex. | |
1879 | */ | |
1880 | if (prctl_map.auxv_size) | |
1881 | memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv)); | |
1882 | ||
1883 | error = 0; | |
1884 | out: | |
1885 | up_read(&mm->mmap_sem); | |
1886 | return error; | |
1887 | } | |
1888 | #endif /* CONFIG_CHECKPOINT_RESTORE */ | |
1889 | ||
028ee4be CG |
1890 | static int prctl_set_mm(int opt, unsigned long addr, |
1891 | unsigned long arg4, unsigned long arg5) | |
1892 | { | |
028ee4be | 1893 | struct mm_struct *mm = current->mm; |
fe8c7f5c CG |
1894 | struct vm_area_struct *vma; |
1895 | int error; | |
028ee4be | 1896 | |
f606b77f CG |
1897 | if (arg5 || (arg4 && (opt != PR_SET_MM_AUXV && |
1898 | opt != PR_SET_MM_MAP && | |
1899 | opt != PR_SET_MM_MAP_SIZE))) | |
028ee4be CG |
1900 | return -EINVAL; |
1901 | ||
f606b77f CG |
1902 | #ifdef CONFIG_CHECKPOINT_RESTORE |
1903 | if (opt == PR_SET_MM_MAP || opt == PR_SET_MM_MAP_SIZE) | |
1904 | return prctl_set_mm_map(opt, (const void __user *)addr, arg4); | |
1905 | #endif | |
1906 | ||
79f0713d | 1907 | if (!capable(CAP_SYS_RESOURCE)) |
028ee4be CG |
1908 | return -EPERM; |
1909 | ||
71fe97e1 CG |
1910 | if (opt == PR_SET_MM_EXE_FILE) { |
1911 | down_write(&mm->mmap_sem); | |
1912 | error = prctl_set_mm_exe_file_locked(mm, (unsigned int)addr); | |
1913 | up_write(&mm->mmap_sem); | |
1914 | return error; | |
1915 | } | |
b32dfe37 | 1916 | |
1ad75b9e | 1917 | if (addr >= TASK_SIZE || addr < mmap_min_addr) |
028ee4be CG |
1918 | return -EINVAL; |
1919 | ||
fe8c7f5c CG |
1920 | error = -EINVAL; |
1921 | ||
028ee4be CG |
1922 | down_read(&mm->mmap_sem); |
1923 | vma = find_vma(mm, addr); | |
1924 | ||
028ee4be CG |
1925 | switch (opt) { |
1926 | case PR_SET_MM_START_CODE: | |
fe8c7f5c CG |
1927 | mm->start_code = addr; |
1928 | break; | |
028ee4be | 1929 | case PR_SET_MM_END_CODE: |
fe8c7f5c | 1930 | mm->end_code = addr; |
028ee4be | 1931 | break; |
028ee4be | 1932 | case PR_SET_MM_START_DATA: |
fe8c7f5c | 1933 | mm->start_data = addr; |
028ee4be | 1934 | break; |
fe8c7f5c CG |
1935 | case PR_SET_MM_END_DATA: |
1936 | mm->end_data = addr; | |
028ee4be CG |
1937 | break; |
1938 | ||
1939 | case PR_SET_MM_START_BRK: | |
1940 | if (addr <= mm->end_data) | |
1941 | goto out; | |
1942 | ||
8764b338 CG |
1943 | if (check_data_rlimit(rlimit(RLIMIT_DATA), mm->brk, addr, |
1944 | mm->end_data, mm->start_data)) | |
028ee4be CG |
1945 | goto out; |
1946 | ||
1947 | mm->start_brk = addr; | |
1948 | break; | |
1949 | ||
1950 | case PR_SET_MM_BRK: | |
1951 | if (addr <= mm->end_data) | |
1952 | goto out; | |
1953 | ||
8764b338 CG |
1954 | if (check_data_rlimit(rlimit(RLIMIT_DATA), addr, mm->start_brk, |
1955 | mm->end_data, mm->start_data)) | |
028ee4be CG |
1956 | goto out; |
1957 | ||
1958 | mm->brk = addr; | |
1959 | break; | |
1960 | ||
fe8c7f5c CG |
1961 | /* |
1962 | * If command line arguments and environment | |
1963 | * are placed somewhere else on stack, we can | |
1964 | * set them up here, ARG_START/END to setup | |
1965 | * command line argumets and ENV_START/END | |
1966 | * for environment. | |
1967 | */ | |
1968 | case PR_SET_MM_START_STACK: | |
1969 | case PR_SET_MM_ARG_START: | |
1970 | case PR_SET_MM_ARG_END: | |
1971 | case PR_SET_MM_ENV_START: | |
1972 | case PR_SET_MM_ENV_END: | |
1973 | if (!vma) { | |
1974 | error = -EFAULT; | |
1975 | goto out; | |
1976 | } | |
fe8c7f5c CG |
1977 | if (opt == PR_SET_MM_START_STACK) |
1978 | mm->start_stack = addr; | |
1979 | else if (opt == PR_SET_MM_ARG_START) | |
1980 | mm->arg_start = addr; | |
1981 | else if (opt == PR_SET_MM_ARG_END) | |
1982 | mm->arg_end = addr; | |
1983 | else if (opt == PR_SET_MM_ENV_START) | |
1984 | mm->env_start = addr; | |
1985 | else if (opt == PR_SET_MM_ENV_END) | |
1986 | mm->env_end = addr; | |
1987 | break; | |
1988 | ||
1989 | /* | |
1990 | * This doesn't move auxiliary vector itself | |
1991 | * since it's pinned to mm_struct, but allow | |
1992 | * to fill vector with new values. It's up | |
1993 | * to a caller to provide sane values here | |
1994 | * otherwise user space tools which use this | |
1995 | * vector might be unhappy. | |
1996 | */ | |
1997 | case PR_SET_MM_AUXV: { | |
1998 | unsigned long user_auxv[AT_VECTOR_SIZE]; | |
1999 | ||
2000 | if (arg4 > sizeof(user_auxv)) | |
2001 | goto out; | |
2002 | up_read(&mm->mmap_sem); | |
2003 | ||
2004 | if (copy_from_user(user_auxv, (const void __user *)addr, arg4)) | |
2005 | return -EFAULT; | |
2006 | ||
2007 | /* Make sure the last entry is always AT_NULL */ | |
2008 | user_auxv[AT_VECTOR_SIZE - 2] = 0; | |
2009 | user_auxv[AT_VECTOR_SIZE - 1] = 0; | |
2010 | ||
2011 | BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); | |
2012 | ||
2013 | task_lock(current); | |
2014 | memcpy(mm->saved_auxv, user_auxv, arg4); | |
2015 | task_unlock(current); | |
2016 | ||
2017 | return 0; | |
2018 | } | |
028ee4be | 2019 | default: |
028ee4be CG |
2020 | goto out; |
2021 | } | |
2022 | ||
2023 | error = 0; | |
028ee4be CG |
2024 | out: |
2025 | up_read(&mm->mmap_sem); | |
028ee4be CG |
2026 | return error; |
2027 | } | |
300f786b | 2028 | |
52b36941 | 2029 | #ifdef CONFIG_CHECKPOINT_RESTORE |
300f786b CG |
2030 | static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr) |
2031 | { | |
2032 | return put_user(me->clear_child_tid, tid_addr); | |
2033 | } | |
52b36941 | 2034 | #else |
300f786b CG |
2035 | static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr) |
2036 | { | |
2037 | return -EINVAL; | |
2038 | } | |
028ee4be CG |
2039 | #endif |
2040 | ||
c4ea37c2 HC |
2041 | SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, |
2042 | unsigned long, arg4, unsigned long, arg5) | |
1da177e4 | 2043 | { |
b6dff3ec DH |
2044 | struct task_struct *me = current; |
2045 | unsigned char comm[sizeof(me->comm)]; | |
2046 | long error; | |
1da177e4 | 2047 | |
d84f4f99 DH |
2048 | error = security_task_prctl(option, arg2, arg3, arg4, arg5); |
2049 | if (error != -ENOSYS) | |
1da177e4 LT |
2050 | return error; |
2051 | ||
d84f4f99 | 2052 | error = 0; |
1da177e4 | 2053 | switch (option) { |
f3cbd435 AM |
2054 | case PR_SET_PDEATHSIG: |
2055 | if (!valid_signal(arg2)) { | |
2056 | error = -EINVAL; | |
1da177e4 | 2057 | break; |
f3cbd435 AM |
2058 | } |
2059 | me->pdeath_signal = arg2; | |
2060 | break; | |
2061 | case PR_GET_PDEATHSIG: | |
2062 | error = put_user(me->pdeath_signal, (int __user *)arg2); | |
2063 | break; | |
2064 | case PR_GET_DUMPABLE: | |
2065 | error = get_dumpable(me->mm); | |
2066 | break; | |
2067 | case PR_SET_DUMPABLE: | |
2068 | if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) { | |
2069 | error = -EINVAL; | |
1da177e4 | 2070 | break; |
f3cbd435 AM |
2071 | } |
2072 | set_dumpable(me->mm, arg2); | |
2073 | break; | |
1da177e4 | 2074 | |
f3cbd435 AM |
2075 | case PR_SET_UNALIGN: |
2076 | error = SET_UNALIGN_CTL(me, arg2); | |
2077 | break; | |
2078 | case PR_GET_UNALIGN: | |
2079 | error = GET_UNALIGN_CTL(me, arg2); | |
2080 | break; | |
2081 | case PR_SET_FPEMU: | |
2082 | error = SET_FPEMU_CTL(me, arg2); | |
2083 | break; | |
2084 | case PR_GET_FPEMU: | |
2085 | error = GET_FPEMU_CTL(me, arg2); | |
2086 | break; | |
2087 | case PR_SET_FPEXC: | |
2088 | error = SET_FPEXC_CTL(me, arg2); | |
2089 | break; | |
2090 | case PR_GET_FPEXC: | |
2091 | error = GET_FPEXC_CTL(me, arg2); | |
2092 | break; | |
2093 | case PR_GET_TIMING: | |
2094 | error = PR_TIMING_STATISTICAL; | |
2095 | break; | |
2096 | case PR_SET_TIMING: | |
2097 | if (arg2 != PR_TIMING_STATISTICAL) | |
2098 | error = -EINVAL; | |
2099 | break; | |
2100 | case PR_SET_NAME: | |
2101 | comm[sizeof(me->comm) - 1] = 0; | |
2102 | if (strncpy_from_user(comm, (char __user *)arg2, | |
2103 | sizeof(me->comm) - 1) < 0) | |
2104 | return -EFAULT; | |
2105 | set_task_comm(me, comm); | |
2106 | proc_comm_connector(me); | |
2107 | break; | |
2108 | case PR_GET_NAME: | |
2109 | get_task_comm(comm, me); | |
2110 | if (copy_to_user((char __user *)arg2, comm, sizeof(comm))) | |
2111 | return -EFAULT; | |
2112 | break; | |
2113 | case PR_GET_ENDIAN: | |
2114 | error = GET_ENDIAN(me, arg2); | |
2115 | break; | |
2116 | case PR_SET_ENDIAN: | |
2117 | error = SET_ENDIAN(me, arg2); | |
2118 | break; | |
2119 | case PR_GET_SECCOMP: | |
2120 | error = prctl_get_seccomp(); | |
2121 | break; | |
2122 | case PR_SET_SECCOMP: | |
2123 | error = prctl_set_seccomp(arg2, (char __user *)arg3); | |
2124 | break; | |
2125 | case PR_GET_TSC: | |
2126 | error = GET_TSC_CTL(arg2); | |
2127 | break; | |
2128 | case PR_SET_TSC: | |
2129 | error = SET_TSC_CTL(arg2); | |
2130 | break; | |
2131 | case PR_TASK_PERF_EVENTS_DISABLE: | |
2132 | error = perf_event_task_disable(); | |
2133 | break; | |
2134 | case PR_TASK_PERF_EVENTS_ENABLE: | |
2135 | error = perf_event_task_enable(); | |
2136 | break; | |
2137 | case PR_GET_TIMERSLACK: | |
2138 | error = current->timer_slack_ns; | |
2139 | break; | |
2140 | case PR_SET_TIMERSLACK: | |
2141 | if (arg2 <= 0) | |
2142 | current->timer_slack_ns = | |
6976675d | 2143 | current->default_timer_slack_ns; |
f3cbd435 AM |
2144 | else |
2145 | current->timer_slack_ns = arg2; | |
2146 | break; | |
2147 | case PR_MCE_KILL: | |
2148 | if (arg4 | arg5) | |
2149 | return -EINVAL; | |
2150 | switch (arg2) { | |
2151 | case PR_MCE_KILL_CLEAR: | |
2152 | if (arg3 != 0) | |
4db96cf0 | 2153 | return -EINVAL; |
f3cbd435 | 2154 | current->flags &= ~PF_MCE_PROCESS; |
4db96cf0 | 2155 | break; |
f3cbd435 AM |
2156 | case PR_MCE_KILL_SET: |
2157 | current->flags |= PF_MCE_PROCESS; | |
2158 | if (arg3 == PR_MCE_KILL_EARLY) | |
2159 | current->flags |= PF_MCE_EARLY; | |
2160 | else if (arg3 == PR_MCE_KILL_LATE) | |
2161 | current->flags &= ~PF_MCE_EARLY; | |
2162 | else if (arg3 == PR_MCE_KILL_DEFAULT) | |
2163 | current->flags &= | |
2164 | ~(PF_MCE_EARLY|PF_MCE_PROCESS); | |
1087e9b4 | 2165 | else |
259e5e6c | 2166 | return -EINVAL; |
259e5e6c | 2167 | break; |
1da177e4 | 2168 | default: |
f3cbd435 AM |
2169 | return -EINVAL; |
2170 | } | |
2171 | break; | |
2172 | case PR_MCE_KILL_GET: | |
2173 | if (arg2 | arg3 | arg4 | arg5) | |
2174 | return -EINVAL; | |
2175 | if (current->flags & PF_MCE_PROCESS) | |
2176 | error = (current->flags & PF_MCE_EARLY) ? | |
2177 | PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE; | |
2178 | else | |
2179 | error = PR_MCE_KILL_DEFAULT; | |
2180 | break; | |
2181 | case PR_SET_MM: | |
2182 | error = prctl_set_mm(arg2, arg3, arg4, arg5); | |
2183 | break; | |
2184 | case PR_GET_TID_ADDRESS: | |
2185 | error = prctl_get_tid_address(me, (int __user **)arg2); | |
2186 | break; | |
2187 | case PR_SET_CHILD_SUBREAPER: | |
2188 | me->signal->is_child_subreaper = !!arg2; | |
2189 | break; | |
2190 | case PR_GET_CHILD_SUBREAPER: | |
2191 | error = put_user(me->signal->is_child_subreaper, | |
2192 | (int __user *)arg2); | |
2193 | break; | |
2194 | case PR_SET_NO_NEW_PRIVS: | |
2195 | if (arg2 != 1 || arg3 || arg4 || arg5) | |
2196 | return -EINVAL; | |
2197 | ||
1d4457f9 | 2198 | task_set_no_new_privs(current); |
f3cbd435 AM |
2199 | break; |
2200 | case PR_GET_NO_NEW_PRIVS: | |
2201 | if (arg2 || arg3 || arg4 || arg5) | |
2202 | return -EINVAL; | |
1d4457f9 | 2203 | return task_no_new_privs(current) ? 1 : 0; |
a0715cc2 AT |
2204 | case PR_GET_THP_DISABLE: |
2205 | if (arg2 || arg3 || arg4 || arg5) | |
2206 | return -EINVAL; | |
2207 | error = !!(me->mm->def_flags & VM_NOHUGEPAGE); | |
2208 | break; | |
2209 | case PR_SET_THP_DISABLE: | |
2210 | if (arg3 || arg4 || arg5) | |
2211 | return -EINVAL; | |
2212 | down_write(&me->mm->mmap_sem); | |
2213 | if (arg2) | |
2214 | me->mm->def_flags |= VM_NOHUGEPAGE; | |
2215 | else | |
2216 | me->mm->def_flags &= ~VM_NOHUGEPAGE; | |
2217 | up_write(&me->mm->mmap_sem); | |
2218 | break; | |
fe3d197f | 2219 | case PR_MPX_ENABLE_MANAGEMENT: |
e9d1b4f3 DH |
2220 | if (arg2 || arg3 || arg4 || arg5) |
2221 | return -EINVAL; | |
fe3d197f DH |
2222 | error = MPX_ENABLE_MANAGEMENT(me); |
2223 | break; | |
2224 | case PR_MPX_DISABLE_MANAGEMENT: | |
e9d1b4f3 DH |
2225 | if (arg2 || arg3 || arg4 || arg5) |
2226 | return -EINVAL; | |
fe3d197f DH |
2227 | error = MPX_DISABLE_MANAGEMENT(me); |
2228 | break; | |
9791554b PB |
2229 | case PR_SET_FP_MODE: |
2230 | error = SET_FP_MODE(me, arg2); | |
2231 | break; | |
2232 | case PR_GET_FP_MODE: | |
2233 | error = GET_FP_MODE(me); | |
2234 | break; | |
f3cbd435 AM |
2235 | default: |
2236 | error = -EINVAL; | |
2237 | break; | |
1da177e4 LT |
2238 | } |
2239 | return error; | |
2240 | } | |
3cfc348b | 2241 | |
836f92ad HC |
2242 | SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep, |
2243 | struct getcpu_cache __user *, unused) | |
3cfc348b AK |
2244 | { |
2245 | int err = 0; | |
2246 | int cpu = raw_smp_processor_id(); | |
ec94fc3d | 2247 | |
3cfc348b AK |
2248 | if (cpup) |
2249 | err |= put_user(cpu, cpup); | |
2250 | if (nodep) | |
2251 | err |= put_user(cpu_to_node(cpu), nodep); | |
3cfc348b AK |
2252 | return err ? -EFAULT : 0; |
2253 | } | |
10a0a8d4 | 2254 | |
4a22f166 SR |
2255 | /** |
2256 | * do_sysinfo - fill in sysinfo struct | |
2257 | * @info: pointer to buffer to fill | |
2258 | */ | |
2259 | static int do_sysinfo(struct sysinfo *info) | |
2260 | { | |
2261 | unsigned long mem_total, sav_total; | |
2262 | unsigned int mem_unit, bitcount; | |
2263 | struct timespec tp; | |
2264 | ||
2265 | memset(info, 0, sizeof(struct sysinfo)); | |
2266 | ||
45c64940 | 2267 | get_monotonic_boottime(&tp); |
4a22f166 SR |
2268 | info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0); |
2269 | ||
2270 | get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT); | |
2271 | ||
2272 | info->procs = nr_threads; | |
2273 | ||
2274 | si_meminfo(info); | |
2275 | si_swapinfo(info); | |
2276 | ||
2277 | /* | |
2278 | * If the sum of all the available memory (i.e. ram + swap) | |
2279 | * is less than can be stored in a 32 bit unsigned long then | |
2280 | * we can be binary compatible with 2.2.x kernels. If not, | |
2281 | * well, in that case 2.2.x was broken anyways... | |
2282 | * | |
2283 | * -Erik Andersen <andersee@debian.org> | |
2284 | */ | |
2285 | ||
2286 | mem_total = info->totalram + info->totalswap; | |
2287 | if (mem_total < info->totalram || mem_total < info->totalswap) | |
2288 | goto out; | |
2289 | bitcount = 0; | |
2290 | mem_unit = info->mem_unit; | |
2291 | while (mem_unit > 1) { | |
2292 | bitcount++; | |
2293 | mem_unit >>= 1; | |
2294 | sav_total = mem_total; | |
2295 | mem_total <<= 1; | |
2296 | if (mem_total < sav_total) | |
2297 | goto out; | |
2298 | } | |
2299 | ||
2300 | /* | |
2301 | * If mem_total did not overflow, multiply all memory values by | |
2302 | * info->mem_unit and set it to 1. This leaves things compatible | |
2303 | * with 2.2.x, and also retains compatibility with earlier 2.4.x | |
2304 | * kernels... | |
2305 | */ | |
2306 | ||
2307 | info->mem_unit = 1; | |
2308 | info->totalram <<= bitcount; | |
2309 | info->freeram <<= bitcount; | |
2310 | info->sharedram <<= bitcount; | |
2311 | info->bufferram <<= bitcount; | |
2312 | info->totalswap <<= bitcount; | |
2313 | info->freeswap <<= bitcount; | |
2314 | info->totalhigh <<= bitcount; | |
2315 | info->freehigh <<= bitcount; | |
2316 | ||
2317 | out: | |
2318 | return 0; | |
2319 | } | |
2320 | ||
2321 | SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info) | |
2322 | { | |
2323 | struct sysinfo val; | |
2324 | ||
2325 | do_sysinfo(&val); | |
2326 | ||
2327 | if (copy_to_user(info, &val, sizeof(struct sysinfo))) | |
2328 | return -EFAULT; | |
2329 | ||
2330 | return 0; | |
2331 | } | |
2332 | ||
2333 | #ifdef CONFIG_COMPAT | |
2334 | struct compat_sysinfo { | |
2335 | s32 uptime; | |
2336 | u32 loads[3]; | |
2337 | u32 totalram; | |
2338 | u32 freeram; | |
2339 | u32 sharedram; | |
2340 | u32 bufferram; | |
2341 | u32 totalswap; | |
2342 | u32 freeswap; | |
2343 | u16 procs; | |
2344 | u16 pad; | |
2345 | u32 totalhigh; | |
2346 | u32 freehigh; | |
2347 | u32 mem_unit; | |
2348 | char _f[20-2*sizeof(u32)-sizeof(int)]; | |
2349 | }; | |
2350 | ||
2351 | COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info) | |
2352 | { | |
2353 | struct sysinfo s; | |
2354 | ||
2355 | do_sysinfo(&s); | |
2356 | ||
2357 | /* Check to see if any memory value is too large for 32-bit and scale | |
2358 | * down if needed | |
2359 | */ | |
0baae41e | 2360 | if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) { |
4a22f166 SR |
2361 | int bitcount = 0; |
2362 | ||
2363 | while (s.mem_unit < PAGE_SIZE) { | |
2364 | s.mem_unit <<= 1; | |
2365 | bitcount++; | |
2366 | } | |
2367 | ||
2368 | s.totalram >>= bitcount; | |
2369 | s.freeram >>= bitcount; | |
2370 | s.sharedram >>= bitcount; | |
2371 | s.bufferram >>= bitcount; | |
2372 | s.totalswap >>= bitcount; | |
2373 | s.freeswap >>= bitcount; | |
2374 | s.totalhigh >>= bitcount; | |
2375 | s.freehigh >>= bitcount; | |
2376 | } | |
2377 | ||
2378 | if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) || | |
2379 | __put_user(s.uptime, &info->uptime) || | |
2380 | __put_user(s.loads[0], &info->loads[0]) || | |
2381 | __put_user(s.loads[1], &info->loads[1]) || | |
2382 | __put_user(s.loads[2], &info->loads[2]) || | |
2383 | __put_user(s.totalram, &info->totalram) || | |
2384 | __put_user(s.freeram, &info->freeram) || | |
2385 | __put_user(s.sharedram, &info->sharedram) || | |
2386 | __put_user(s.bufferram, &info->bufferram) || | |
2387 | __put_user(s.totalswap, &info->totalswap) || | |
2388 | __put_user(s.freeswap, &info->freeswap) || | |
2389 | __put_user(s.procs, &info->procs) || | |
2390 | __put_user(s.totalhigh, &info->totalhigh) || | |
2391 | __put_user(s.freehigh, &info->freehigh) || | |
2392 | __put_user(s.mem_unit, &info->mem_unit)) | |
2393 | return -EFAULT; | |
2394 | ||
2395 | return 0; | |
2396 | } | |
2397 | #endif /* CONFIG_COMPAT */ |