1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/kernel/sys.c 4 * 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 */ 7 8 #include <linux/export.h> 9 #include <linux/mm.h> 10 #include <linux/mm_inline.h> 11 #include <linux/utsname.h> 12 #include <linux/mman.h> 13 #include <linux/reboot.h> 14 #include <linux/prctl.h> 15 #include <linux/highuid.h> 16 #include <linux/fs.h> 17 #include <linux/kmod.h> 18 #include <linux/perf_event.h> 19 #include <linux/resource.h> 20 #include <linux/kernel.h> 21 #include <linux/workqueue.h> 22 #include <linux/capability.h> 23 #include <linux/device.h> 24 #include <linux/key.h> 25 #include <linux/times.h> 26 #include <linux/posix-timers.h> 27 #include <linux/security.h> 28 #include <linux/suspend.h> 29 #include <linux/tty.h> 30 #include <linux/signal.h> 31 #include <linux/cn_proc.h> 32 #include <linux/getcpu.h> 33 #include <linux/task_io_accounting_ops.h> 34 #include <linux/seccomp.h> 35 #include <linux/cpu.h> 36 #include <linux/personality.h> 37 #include <linux/ptrace.h> 38 #include <linux/fs_struct.h> 39 #include <linux/file.h> 40 #include <linux/mount.h> 41 #include <linux/gfp.h> 42 #include <linux/syscore_ops.h> 43 #include <linux/version.h> 44 #include <linux/ctype.h> 45 #include <linux/syscall_user_dispatch.h> 46 47 #include <linux/compat.h> 48 #include <linux/syscalls.h> 49 #include <linux/kprobes.h> 50 #include <linux/user_namespace.h> 51 #include <linux/time_namespace.h> 52 #include <linux/binfmts.h> 53 54 #include <linux/sched.h> 55 #include <linux/sched/autogroup.h> 56 #include <linux/sched/loadavg.h> 57 #include <linux/sched/stat.h> 58 #include <linux/sched/mm.h> 59 #include <linux/sched/coredump.h> 60 #include <linux/sched/task.h> 61 #include <linux/sched/cputime.h> 62 #include <linux/rcupdate.h> 63 #include <linux/uidgid.h> 64 #include <linux/cred.h> 65 66 #include <linux/nospec.h> 67 68 #include <linux/kmsg_dump.h> 69 /* Move somewhere else to avoid recompiling? */ 70 #include <generated/utsrelease.h> 71 72 #include <linux/uaccess.h> 73 #include <asm/io.h> 74 #include <asm/unistd.h> 75 76 #include "uid16.h" 77 78 #ifndef SET_UNALIGN_CTL 79 # define SET_UNALIGN_CTL(a, b) (-EINVAL) 80 #endif 81 #ifndef GET_UNALIGN_CTL 82 # define GET_UNALIGN_CTL(a, b) (-EINVAL) 83 #endif 84 #ifndef SET_FPEMU_CTL 85 # define SET_FPEMU_CTL(a, b) (-EINVAL) 86 #endif 87 #ifndef GET_FPEMU_CTL 88 # define GET_FPEMU_CTL(a, b) (-EINVAL) 89 #endif 90 #ifndef SET_FPEXC_CTL 91 # define SET_FPEXC_CTL(a, b) (-EINVAL) 92 #endif 93 #ifndef GET_FPEXC_CTL 94 # define GET_FPEXC_CTL(a, b) (-EINVAL) 95 #endif 96 #ifndef GET_ENDIAN 97 # define GET_ENDIAN(a, b) (-EINVAL) 98 #endif 99 #ifndef SET_ENDIAN 100 # define SET_ENDIAN(a, b) (-EINVAL) 101 #endif 102 #ifndef GET_TSC_CTL 103 # define GET_TSC_CTL(a) (-EINVAL) 104 #endif 105 #ifndef SET_TSC_CTL 106 # define SET_TSC_CTL(a) (-EINVAL) 107 #endif 108 #ifndef GET_FP_MODE 109 # define GET_FP_MODE(a) (-EINVAL) 110 #endif 111 #ifndef SET_FP_MODE 112 # define SET_FP_MODE(a,b) (-EINVAL) 113 #endif 114 #ifndef SVE_SET_VL 115 # define SVE_SET_VL(a) (-EINVAL) 116 #endif 117 #ifndef SVE_GET_VL 118 # define SVE_GET_VL() (-EINVAL) 119 #endif 120 #ifndef SME_SET_VL 121 # define SME_SET_VL(a) (-EINVAL) 122 #endif 123 #ifndef SME_GET_VL 124 # define SME_GET_VL() (-EINVAL) 125 #endif 126 #ifndef PAC_RESET_KEYS 127 # define PAC_RESET_KEYS(a, b) (-EINVAL) 128 #endif 129 #ifndef PAC_SET_ENABLED_KEYS 130 # define PAC_SET_ENABLED_KEYS(a, b, c) (-EINVAL) 131 #endif 132 #ifndef PAC_GET_ENABLED_KEYS 133 # define PAC_GET_ENABLED_KEYS(a) (-EINVAL) 134 #endif 135 #ifndef SET_TAGGED_ADDR_CTRL 136 # define SET_TAGGED_ADDR_CTRL(a) (-EINVAL) 137 #endif 138 #ifndef GET_TAGGED_ADDR_CTRL 139 # define GET_TAGGED_ADDR_CTRL() (-EINVAL) 140 #endif 141 142 /* 143 * this is where the system-wide overflow UID and GID are defined, for 144 * architectures that now have 32-bit UID/GID but didn't in the past 145 */ 146 147 int overflowuid = DEFAULT_OVERFLOWUID; 148 int overflowgid = DEFAULT_OVERFLOWGID; 149 150 EXPORT_SYMBOL(overflowuid); 151 EXPORT_SYMBOL(overflowgid); 152 153 /* 154 * the same as above, but for filesystems which can only store a 16-bit 155 * UID and GID. as such, this is needed on all architectures 156 */ 157 158 int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; 159 int fs_overflowgid = DEFAULT_FS_OVERFLOWGID; 160 161 EXPORT_SYMBOL(fs_overflowuid); 162 EXPORT_SYMBOL(fs_overflowgid); 163 164 /* 165 * Returns true if current's euid is same as p's uid or euid, 166 * or has CAP_SYS_NICE to p's user_ns. 167 * 168 * Called with rcu_read_lock, creds are safe 169 */ 170 static bool set_one_prio_perm(struct task_struct *p) 171 { 172 const struct cred *cred = current_cred(), *pcred = __task_cred(p); 173 174 if (uid_eq(pcred->uid, cred->euid) || 175 uid_eq(pcred->euid, cred->euid)) 176 return true; 177 if (ns_capable(pcred->user_ns, CAP_SYS_NICE)) 178 return true; 179 return false; 180 } 181 182 /* 183 * set the priority of a task 184 * - the caller must hold the RCU read lock 185 */ 186 static int set_one_prio(struct task_struct *p, int niceval, int error) 187 { 188 int no_nice; 189 190 if (!set_one_prio_perm(p)) { 191 error = -EPERM; 192 goto out; 193 } 194 if (niceval < task_nice(p) && !can_nice(p, niceval)) { 195 error = -EACCES; 196 goto out; 197 } 198 no_nice = security_task_setnice(p, niceval); 199 if (no_nice) { 200 error = no_nice; 201 goto out; 202 } 203 if (error == -ESRCH) 204 error = 0; 205 set_user_nice(p, niceval); 206 out: 207 return error; 208 } 209 210 SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval) 211 { 212 struct task_struct *g, *p; 213 struct user_struct *user; 214 const struct cred *cred = current_cred(); 215 int error = -EINVAL; 216 struct pid *pgrp; 217 kuid_t uid; 218 219 if (which > PRIO_USER || which < PRIO_PROCESS) 220 goto out; 221 222 /* normalize: avoid signed division (rounding problems) */ 223 error = -ESRCH; 224 if (niceval < MIN_NICE) 225 niceval = MIN_NICE; 226 if (niceval > MAX_NICE) 227 niceval = MAX_NICE; 228 229 rcu_read_lock(); 230 switch (which) { 231 case PRIO_PROCESS: 232 if (who) 233 p = find_task_by_vpid(who); 234 else 235 p = current; 236 if (p) 237 error = set_one_prio(p, niceval, error); 238 break; 239 case PRIO_PGRP: 240 if (who) 241 pgrp = find_vpid(who); 242 else 243 pgrp = task_pgrp(current); 244 read_lock(&tasklist_lock); 245 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { 246 error = set_one_prio(p, niceval, error); 247 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); 248 read_unlock(&tasklist_lock); 249 break; 250 case PRIO_USER: 251 uid = make_kuid(cred->user_ns, who); 252 user = cred->user; 253 if (!who) 254 uid = cred->uid; 255 else if (!uid_eq(uid, cred->uid)) { 256 user = find_user(uid); 257 if (!user) 258 goto out_unlock; /* No processes for this user */ 259 } 260 for_each_process_thread(g, p) { 261 if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) 262 error = set_one_prio(p, niceval, error); 263 } 264 if (!uid_eq(uid, cred->uid)) 265 free_uid(user); /* For find_user() */ 266 break; 267 } 268 out_unlock: 269 rcu_read_unlock(); 270 out: 271 return error; 272 } 273 274 /* 275 * Ugh. To avoid negative return values, "getpriority()" will 276 * not return the normal nice-value, but a negated value that 277 * has been offset by 20 (ie it returns 40..1 instead of -20..19) 278 * to stay compatible. 279 */ 280 SYSCALL_DEFINE2(getpriority, int, which, int, who) 281 { 282 struct task_struct *g, *p; 283 struct user_struct *user; 284 const struct cred *cred = current_cred(); 285 long niceval, retval = -ESRCH; 286 struct pid *pgrp; 287 kuid_t uid; 288 289 if (which > PRIO_USER || which < PRIO_PROCESS) 290 return -EINVAL; 291 292 rcu_read_lock(); 293 switch (which) { 294 case PRIO_PROCESS: 295 if (who) 296 p = find_task_by_vpid(who); 297 else 298 p = current; 299 if (p) { 300 niceval = nice_to_rlimit(task_nice(p)); 301 if (niceval > retval) 302 retval = niceval; 303 } 304 break; 305 case PRIO_PGRP: 306 if (who) 307 pgrp = find_vpid(who); 308 else 309 pgrp = task_pgrp(current); 310 read_lock(&tasklist_lock); 311 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { 312 niceval = nice_to_rlimit(task_nice(p)); 313 if (niceval > retval) 314 retval = niceval; 315 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); 316 read_unlock(&tasklist_lock); 317 break; 318 case PRIO_USER: 319 uid = make_kuid(cred->user_ns, who); 320 user = cred->user; 321 if (!who) 322 uid = cred->uid; 323 else if (!uid_eq(uid, cred->uid)) { 324 user = find_user(uid); 325 if (!user) 326 goto out_unlock; /* No processes for this user */ 327 } 328 for_each_process_thread(g, p) { 329 if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) { 330 niceval = nice_to_rlimit(task_nice(p)); 331 if (niceval > retval) 332 retval = niceval; 333 } 334 } 335 if (!uid_eq(uid, cred->uid)) 336 free_uid(user); /* for find_user() */ 337 break; 338 } 339 out_unlock: 340 rcu_read_unlock(); 341 342 return retval; 343 } 344 345 /* 346 * Unprivileged users may change the real gid to the effective gid 347 * or vice versa. (BSD-style) 348 * 349 * If you set the real gid at all, or set the effective gid to a value not 350 * equal to the real gid, then the saved gid is set to the new effective gid. 351 * 352 * This makes it possible for a setgid program to completely drop its 353 * privileges, which is often a useful assertion to make when you are doing 354 * a security audit over a program. 355 * 356 * The general idea is that a program which uses just setregid() will be 357 * 100% compatible with BSD. A program which uses just setgid() will be 358 * 100% compatible with POSIX with saved IDs. 359 * 360 * SMP: There are not races, the GIDs are checked only by filesystem 361 * operations (as far as semantic preservation is concerned). 362 */ 363 #ifdef CONFIG_MULTIUSER 364 long __sys_setregid(gid_t rgid, gid_t egid) 365 { 366 struct user_namespace *ns = current_user_ns(); 367 const struct cred *old; 368 struct cred *new; 369 int retval; 370 kgid_t krgid, kegid; 371 372 krgid = make_kgid(ns, rgid); 373 kegid = make_kgid(ns, egid); 374 375 if ((rgid != (gid_t) -1) && !gid_valid(krgid)) 376 return -EINVAL; 377 if ((egid != (gid_t) -1) && !gid_valid(kegid)) 378 return -EINVAL; 379 380 new = prepare_creds(); 381 if (!new) 382 return -ENOMEM; 383 old = current_cred(); 384 385 retval = -EPERM; 386 if (rgid != (gid_t) -1) { 387 if (gid_eq(old->gid, krgid) || 388 gid_eq(old->egid, krgid) || 389 ns_capable_setid(old->user_ns, CAP_SETGID)) 390 new->gid = krgid; 391 else 392 goto error; 393 } 394 if (egid != (gid_t) -1) { 395 if (gid_eq(old->gid, kegid) || 396 gid_eq(old->egid, kegid) || 397 gid_eq(old->sgid, kegid) || 398 ns_capable_setid(old->user_ns, CAP_SETGID)) 399 new->egid = kegid; 400 else 401 goto error; 402 } 403 404 if (rgid != (gid_t) -1 || 405 (egid != (gid_t) -1 && !gid_eq(kegid, old->gid))) 406 new->sgid = new->egid; 407 new->fsgid = new->egid; 408 409 retval = security_task_fix_setgid(new, old, LSM_SETID_RE); 410 if (retval < 0) 411 goto error; 412 413 return commit_creds(new); 414 415 error: 416 abort_creds(new); 417 return retval; 418 } 419 420 SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) 421 { 422 return __sys_setregid(rgid, egid); 423 } 424 425 /* 426 * setgid() is implemented like SysV w/ SAVED_IDS 427 * 428 * SMP: Same implicit races as above. 429 */ 430 long __sys_setgid(gid_t gid) 431 { 432 struct user_namespace *ns = current_user_ns(); 433 const struct cred *old; 434 struct cred *new; 435 int retval; 436 kgid_t kgid; 437 438 kgid = make_kgid(ns, gid); 439 if (!gid_valid(kgid)) 440 return -EINVAL; 441 442 new = prepare_creds(); 443 if (!new) 444 return -ENOMEM; 445 old = current_cred(); 446 447 retval = -EPERM; 448 if (ns_capable_setid(old->user_ns, CAP_SETGID)) 449 new->gid = new->egid = new->sgid = new->fsgid = kgid; 450 else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid)) 451 new->egid = new->fsgid = kgid; 452 else 453 goto error; 454 455 retval = security_task_fix_setgid(new, old, LSM_SETID_ID); 456 if (retval < 0) 457 goto error; 458 459 return commit_creds(new); 460 461 error: 462 abort_creds(new); 463 return retval; 464 } 465 466 SYSCALL_DEFINE1(setgid, gid_t, gid) 467 { 468 return __sys_setgid(gid); 469 } 470 471 /* 472 * change the user struct in a credentials set to match the new UID 473 */ 474 static int set_user(struct cred *new) 475 { 476 struct user_struct *new_user; 477 478 new_user = alloc_uid(new->uid); 479 if (!new_user) 480 return -EAGAIN; 481 482 free_uid(new->user); 483 new->user = new_user; 484 return 0; 485 } 486 487 static void flag_nproc_exceeded(struct cred *new) 488 { 489 if (new->ucounts == current_ucounts()) 490 return; 491 492 /* 493 * We don't fail in case of NPROC limit excess here because too many 494 * poorly written programs don't check set*uid() return code, assuming 495 * it never fails if called by root. We may still enforce NPROC limit 496 * for programs doing set*uid()+execve() by harmlessly deferring the 497 * failure to the execve() stage. 498 */ 499 if (is_ucounts_overlimit(new->ucounts, UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC)) && 500 new->user != INIT_USER) 501 current->flags |= PF_NPROC_EXCEEDED; 502 else 503 current->flags &= ~PF_NPROC_EXCEEDED; 504 } 505 506 /* 507 * Unprivileged users may change the real uid to the effective uid 508 * or vice versa. (BSD-style) 509 * 510 * If you set the real uid at all, or set the effective uid to a value not 511 * equal to the real uid, then the saved uid is set to the new effective uid. 512 * 513 * This makes it possible for a setuid program to completely drop its 514 * privileges, which is often a useful assertion to make when you are doing 515 * a security audit over a program. 516 * 517 * The general idea is that a program which uses just setreuid() will be 518 * 100% compatible with BSD. A program which uses just setuid() will be 519 * 100% compatible with POSIX with saved IDs. 520 */ 521 long __sys_setreuid(uid_t ruid, uid_t euid) 522 { 523 struct user_namespace *ns = current_user_ns(); 524 const struct cred *old; 525 struct cred *new; 526 int retval; 527 kuid_t kruid, keuid; 528 529 kruid = make_kuid(ns, ruid); 530 keuid = make_kuid(ns, euid); 531 532 if ((ruid != (uid_t) -1) && !uid_valid(kruid)) 533 return -EINVAL; 534 if ((euid != (uid_t) -1) && !uid_valid(keuid)) 535 return -EINVAL; 536 537 new = prepare_creds(); 538 if (!new) 539 return -ENOMEM; 540 old = current_cred(); 541 542 retval = -EPERM; 543 if (ruid != (uid_t) -1) { 544 new->uid = kruid; 545 if (!uid_eq(old->uid, kruid) && 546 !uid_eq(old->euid, kruid) && 547 !ns_capable_setid(old->user_ns, CAP_SETUID)) 548 goto error; 549 } 550 551 if (euid != (uid_t) -1) { 552 new->euid = keuid; 553 if (!uid_eq(old->uid, keuid) && 554 !uid_eq(old->euid, keuid) && 555 !uid_eq(old->suid, keuid) && 556 !ns_capable_setid(old->user_ns, CAP_SETUID)) 557 goto error; 558 } 559 560 if (!uid_eq(new->uid, old->uid)) { 561 retval = set_user(new); 562 if (retval < 0) 563 goto error; 564 } 565 if (ruid != (uid_t) -1 || 566 (euid != (uid_t) -1 && !uid_eq(keuid, old->uid))) 567 new->suid = new->euid; 568 new->fsuid = new->euid; 569 570 retval = security_task_fix_setuid(new, old, LSM_SETID_RE); 571 if (retval < 0) 572 goto error; 573 574 retval = set_cred_ucounts(new); 575 if (retval < 0) 576 goto error; 577 578 flag_nproc_exceeded(new); 579 return commit_creds(new); 580 581 error: 582 abort_creds(new); 583 return retval; 584 } 585 586 SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) 587 { 588 return __sys_setreuid(ruid, euid); 589 } 590 591 /* 592 * setuid() is implemented like SysV with SAVED_IDS 593 * 594 * Note that SAVED_ID's is deficient in that a setuid root program 595 * like sendmail, for example, cannot set its uid to be a normal 596 * user and then switch back, because if you're root, setuid() sets 597 * the saved uid too. If you don't like this, blame the bright people 598 * in the POSIX committee and/or USG. Note that the BSD-style setreuid() 599 * will allow a root program to temporarily drop privileges and be able to 600 * regain them by swapping the real and effective uid. 601 */ 602 long __sys_setuid(uid_t uid) 603 { 604 struct user_namespace *ns = current_user_ns(); 605 const struct cred *old; 606 struct cred *new; 607 int retval; 608 kuid_t kuid; 609 610 kuid = make_kuid(ns, uid); 611 if (!uid_valid(kuid)) 612 return -EINVAL; 613 614 new = prepare_creds(); 615 if (!new) 616 return -ENOMEM; 617 old = current_cred(); 618 619 retval = -EPERM; 620 if (ns_capable_setid(old->user_ns, CAP_SETUID)) { 621 new->suid = new->uid = kuid; 622 if (!uid_eq(kuid, old->uid)) { 623 retval = set_user(new); 624 if (retval < 0) 625 goto error; 626 } 627 } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) { 628 goto error; 629 } 630 631 new->fsuid = new->euid = kuid; 632 633 retval = security_task_fix_setuid(new, old, LSM_SETID_ID); 634 if (retval < 0) 635 goto error; 636 637 retval = set_cred_ucounts(new); 638 if (retval < 0) 639 goto error; 640 641 flag_nproc_exceeded(new); 642 return commit_creds(new); 643 644 error: 645 abort_creds(new); 646 return retval; 647 } 648 649 SYSCALL_DEFINE1(setuid, uid_t, uid) 650 { 651 return __sys_setuid(uid); 652 } 653 654 655 /* 656 * This function implements a generic ability to update ruid, euid, 657 * and suid. This allows you to implement the 4.4 compatible seteuid(). 658 */ 659 long __sys_setresuid(uid_t ruid, uid_t euid, uid_t suid) 660 { 661 struct user_namespace *ns = current_user_ns(); 662 const struct cred *old; 663 struct cred *new; 664 int retval; 665 kuid_t kruid, keuid, ksuid; 666 667 kruid = make_kuid(ns, ruid); 668 keuid = make_kuid(ns, euid); 669 ksuid = make_kuid(ns, suid); 670 671 if ((ruid != (uid_t) -1) && !uid_valid(kruid)) 672 return -EINVAL; 673 674 if ((euid != (uid_t) -1) && !uid_valid(keuid)) 675 return -EINVAL; 676 677 if ((suid != (uid_t) -1) && !uid_valid(ksuid)) 678 return -EINVAL; 679 680 new = prepare_creds(); 681 if (!new) 682 return -ENOMEM; 683 684 old = current_cred(); 685 686 retval = -EPERM; 687 if (!ns_capable_setid(old->user_ns, CAP_SETUID)) { 688 if (ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) && 689 !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid)) 690 goto error; 691 if (euid != (uid_t) -1 && !uid_eq(keuid, old->uid) && 692 !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid)) 693 goto error; 694 if (suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) && 695 !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid)) 696 goto error; 697 } 698 699 if (ruid != (uid_t) -1) { 700 new->uid = kruid; 701 if (!uid_eq(kruid, old->uid)) { 702 retval = set_user(new); 703 if (retval < 0) 704 goto error; 705 } 706 } 707 if (euid != (uid_t) -1) 708 new->euid = keuid; 709 if (suid != (uid_t) -1) 710 new->suid = ksuid; 711 new->fsuid = new->euid; 712 713 retval = security_task_fix_setuid(new, old, LSM_SETID_RES); 714 if (retval < 0) 715 goto error; 716 717 retval = set_cred_ucounts(new); 718 if (retval < 0) 719 goto error; 720 721 flag_nproc_exceeded(new); 722 return commit_creds(new); 723 724 error: 725 abort_creds(new); 726 return retval; 727 } 728 729 SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) 730 { 731 return __sys_setresuid(ruid, euid, suid); 732 } 733 734 SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp) 735 { 736 const struct cred *cred = current_cred(); 737 int retval; 738 uid_t ruid, euid, suid; 739 740 ruid = from_kuid_munged(cred->user_ns, cred->uid); 741 euid = from_kuid_munged(cred->user_ns, cred->euid); 742 suid = from_kuid_munged(cred->user_ns, cred->suid); 743 744 retval = put_user(ruid, ruidp); 745 if (!retval) { 746 retval = put_user(euid, euidp); 747 if (!retval) 748 return put_user(suid, suidp); 749 } 750 return retval; 751 } 752 753 /* 754 * Same as above, but for rgid, egid, sgid. 755 */ 756 long __sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid) 757 { 758 struct user_namespace *ns = current_user_ns(); 759 const struct cred *old; 760 struct cred *new; 761 int retval; 762 kgid_t krgid, kegid, ksgid; 763 764 krgid = make_kgid(ns, rgid); 765 kegid = make_kgid(ns, egid); 766 ksgid = make_kgid(ns, sgid); 767 768 if ((rgid != (gid_t) -1) && !gid_valid(krgid)) 769 return -EINVAL; 770 if ((egid != (gid_t) -1) && !gid_valid(kegid)) 771 return -EINVAL; 772 if ((sgid != (gid_t) -1) && !gid_valid(ksgid)) 773 return -EINVAL; 774 775 new = prepare_creds(); 776 if (!new) 777 return -ENOMEM; 778 old = current_cred(); 779 780 retval = -EPERM; 781 if (!ns_capable_setid(old->user_ns, CAP_SETGID)) { 782 if (rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) && 783 !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid)) 784 goto error; 785 if (egid != (gid_t) -1 && !gid_eq(kegid, old->gid) && 786 !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid)) 787 goto error; 788 if (sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) && 789 !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid)) 790 goto error; 791 } 792 793 if (rgid != (gid_t) -1) 794 new->gid = krgid; 795 if (egid != (gid_t) -1) 796 new->egid = kegid; 797 if (sgid != (gid_t) -1) 798 new->sgid = ksgid; 799 new->fsgid = new->egid; 800 801 retval = security_task_fix_setgid(new, old, LSM_SETID_RES); 802 if (retval < 0) 803 goto error; 804 805 return commit_creds(new); 806 807 error: 808 abort_creds(new); 809 return retval; 810 } 811 812 SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) 813 { 814 return __sys_setresgid(rgid, egid, sgid); 815 } 816 817 SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp) 818 { 819 const struct cred *cred = current_cred(); 820 int retval; 821 gid_t rgid, egid, sgid; 822 823 rgid = from_kgid_munged(cred->user_ns, cred->gid); 824 egid = from_kgid_munged(cred->user_ns, cred->egid); 825 sgid = from_kgid_munged(cred->user_ns, cred->sgid); 826 827 retval = put_user(rgid, rgidp); 828 if (!retval) { 829 retval = put_user(egid, egidp); 830 if (!retval) 831 retval = put_user(sgid, sgidp); 832 } 833 834 return retval; 835 } 836 837 838 /* 839 * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This 840 * is used for "access()" and for the NFS daemon (letting nfsd stay at 841 * whatever uid it wants to). It normally shadows "euid", except when 842 * explicitly set by setfsuid() or for access.. 843 */ 844 long __sys_setfsuid(uid_t uid) 845 { 846 const struct cred *old; 847 struct cred *new; 848 uid_t old_fsuid; 849 kuid_t kuid; 850 851 old = current_cred(); 852 old_fsuid = from_kuid_munged(old->user_ns, old->fsuid); 853 854 kuid = make_kuid(old->user_ns, uid); 855 if (!uid_valid(kuid)) 856 return old_fsuid; 857 858 new = prepare_creds(); 859 if (!new) 860 return old_fsuid; 861 862 if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) || 863 uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) || 864 ns_capable_setid(old->user_ns, CAP_SETUID)) { 865 if (!uid_eq(kuid, old->fsuid)) { 866 new->fsuid = kuid; 867 if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) 868 goto change_okay; 869 } 870 } 871 872 abort_creds(new); 873 return old_fsuid; 874 875 change_okay: 876 commit_creds(new); 877 return old_fsuid; 878 } 879 880 SYSCALL_DEFINE1(setfsuid, uid_t, uid) 881 { 882 return __sys_setfsuid(uid); 883 } 884 885 /* 886 * Samma på svenska.. 887 */ 888 long __sys_setfsgid(gid_t gid) 889 { 890 const struct cred *old; 891 struct cred *new; 892 gid_t old_fsgid; 893 kgid_t kgid; 894 895 old = current_cred(); 896 old_fsgid = from_kgid_munged(old->user_ns, old->fsgid); 897 898 kgid = make_kgid(old->user_ns, gid); 899 if (!gid_valid(kgid)) 900 return old_fsgid; 901 902 new = prepare_creds(); 903 if (!new) 904 return old_fsgid; 905 906 if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) || 907 gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) || 908 ns_capable_setid(old->user_ns, CAP_SETGID)) { 909 if (!gid_eq(kgid, old->fsgid)) { 910 new->fsgid = kgid; 911 if (security_task_fix_setgid(new,old,LSM_SETID_FS) == 0) 912 goto change_okay; 913 } 914 } 915 916 abort_creds(new); 917 return old_fsgid; 918 919 change_okay: 920 commit_creds(new); 921 return old_fsgid; 922 } 923 924 SYSCALL_DEFINE1(setfsgid, gid_t, gid) 925 { 926 return __sys_setfsgid(gid); 927 } 928 #endif /* CONFIG_MULTIUSER */ 929 930 /** 931 * sys_getpid - return the thread group id of the current process 932 * 933 * Note, despite the name, this returns the tgid not the pid. The tgid and 934 * the pid are identical unless CLONE_THREAD was specified on clone() in 935 * which case the tgid is the same in all threads of the same group. 936 * 937 * This is SMP safe as current->tgid does not change. 938 */ 939 SYSCALL_DEFINE0(getpid) 940 { 941 return task_tgid_vnr(current); 942 } 943 944 /* Thread ID - the internal kernel "pid" */ 945 SYSCALL_DEFINE0(gettid) 946 { 947 return task_pid_vnr(current); 948 } 949 950 /* 951 * Accessing ->real_parent is not SMP-safe, it could 952 * change from under us. However, we can use a stale 953 * value of ->real_parent under rcu_read_lock(), see 954 * release_task()->call_rcu(delayed_put_task_struct). 955 */ 956 SYSCALL_DEFINE0(getppid) 957 { 958 int pid; 959 960 rcu_read_lock(); 961 pid = task_tgid_vnr(rcu_dereference(current->real_parent)); 962 rcu_read_unlock(); 963 964 return pid; 965 } 966 967 SYSCALL_DEFINE0(getuid) 968 { 969 /* Only we change this so SMP safe */ 970 return from_kuid_munged(current_user_ns(), current_uid()); 971 } 972 973 SYSCALL_DEFINE0(geteuid) 974 { 975 /* Only we change this so SMP safe */ 976 return from_kuid_munged(current_user_ns(), current_euid()); 977 } 978 979 SYSCALL_DEFINE0(getgid) 980 { 981 /* Only we change this so SMP safe */ 982 return from_kgid_munged(current_user_ns(), current_gid()); 983 } 984 985 SYSCALL_DEFINE0(getegid) 986 { 987 /* Only we change this so SMP safe */ 988 return from_kgid_munged(current_user_ns(), current_egid()); 989 } 990 991 static void do_sys_times(struct tms *tms) 992 { 993 u64 tgutime, tgstime, cutime, cstime; 994 995 thread_group_cputime_adjusted(current, &tgutime, &tgstime); 996 cutime = current->signal->cutime; 997 cstime = current->signal->cstime; 998 tms->tms_utime = nsec_to_clock_t(tgutime); 999 tms->tms_stime = nsec_to_clock_t(tgstime); 1000 tms->tms_cutime = nsec_to_clock_t(cutime); 1001 tms->tms_cstime = nsec_to_clock_t(cstime); 1002 } 1003 1004 SYSCALL_DEFINE1(times, struct tms __user *, tbuf) 1005 { 1006 if (tbuf) { 1007 struct tms tmp; 1008 1009 do_sys_times(&tmp); 1010 if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) 1011 return -EFAULT; 1012 } 1013 force_successful_syscall_return(); 1014 return (long) jiffies_64_to_clock_t(get_jiffies_64()); 1015 } 1016 1017 #ifdef CONFIG_COMPAT 1018 static compat_clock_t clock_t_to_compat_clock_t(clock_t x) 1019 { 1020 return compat_jiffies_to_clock_t(clock_t_to_jiffies(x)); 1021 } 1022 1023 COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf) 1024 { 1025 if (tbuf) { 1026 struct tms tms; 1027 struct compat_tms tmp; 1028 1029 do_sys_times(&tms); 1030 /* Convert our struct tms to the compat version. */ 1031 tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime); 1032 tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime); 1033 tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime); 1034 tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime); 1035 if (copy_to_user(tbuf, &tmp, sizeof(tmp))) 1036 return -EFAULT; 1037 } 1038 force_successful_syscall_return(); 1039 return compat_jiffies_to_clock_t(jiffies); 1040 } 1041 #endif 1042 1043 /* 1044 * This needs some heavy checking ... 1045 * I just haven't the stomach for it. I also don't fully 1046 * understand sessions/pgrp etc. Let somebody who does explain it. 1047 * 1048 * OK, I think I have the protection semantics right.... this is really 1049 * only important on a multi-user system anyway, to make sure one user 1050 * can't send a signal to a process owned by another. -TYT, 12/12/91 1051 * 1052 * !PF_FORKNOEXEC check to conform completely to POSIX. 1053 */ 1054 SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) 1055 { 1056 struct task_struct *p; 1057 struct task_struct *group_leader = current->group_leader; 1058 struct pid *pgrp; 1059 int err; 1060 1061 if (!pid) 1062 pid = task_pid_vnr(group_leader); 1063 if (!pgid) 1064 pgid = pid; 1065 if (pgid < 0) 1066 return -EINVAL; 1067 rcu_read_lock(); 1068 1069 /* From this point forward we keep holding onto the tasklist lock 1070 * so that our parent does not change from under us. -DaveM 1071 */ 1072 write_lock_irq(&tasklist_lock); 1073 1074 err = -ESRCH; 1075 p = find_task_by_vpid(pid); 1076 if (!p) 1077 goto out; 1078 1079 err = -EINVAL; 1080 if (!thread_group_leader(p)) 1081 goto out; 1082 1083 if (same_thread_group(p->real_parent, group_leader)) { 1084 err = -EPERM; 1085 if (task_session(p) != task_session(group_leader)) 1086 goto out; 1087 err = -EACCES; 1088 if (!(p->flags & PF_FORKNOEXEC)) 1089 goto out; 1090 } else { 1091 err = -ESRCH; 1092 if (p != group_leader) 1093 goto out; 1094 } 1095 1096 err = -EPERM; 1097 if (p->signal->leader) 1098 goto out; 1099 1100 pgrp = task_pid(p); 1101 if (pgid != pid) { 1102 struct task_struct *g; 1103 1104 pgrp = find_vpid(pgid); 1105 g = pid_task(pgrp, PIDTYPE_PGID); 1106 if (!g || task_session(g) != task_session(group_leader)) 1107 goto out; 1108 } 1109 1110 err = security_task_setpgid(p, pgid); 1111 if (err) 1112 goto out; 1113 1114 if (task_pgrp(p) != pgrp) 1115 change_pid(p, PIDTYPE_PGID, pgrp); 1116 1117 err = 0; 1118 out: 1119 /* All paths lead to here, thus we are safe. -DaveM */ 1120 write_unlock_irq(&tasklist_lock); 1121 rcu_read_unlock(); 1122 return err; 1123 } 1124 1125 static int do_getpgid(pid_t pid) 1126 { 1127 struct task_struct *p; 1128 struct pid *grp; 1129 int retval; 1130 1131 rcu_read_lock(); 1132 if (!pid) 1133 grp = task_pgrp(current); 1134 else { 1135 retval = -ESRCH; 1136 p = find_task_by_vpid(pid); 1137 if (!p) 1138 goto out; 1139 grp = task_pgrp(p); 1140 if (!grp) 1141 goto out; 1142 1143 retval = security_task_getpgid(p); 1144 if (retval) 1145 goto out; 1146 } 1147 retval = pid_vnr(grp); 1148 out: 1149 rcu_read_unlock(); 1150 return retval; 1151 } 1152 1153 SYSCALL_DEFINE1(getpgid, pid_t, pid) 1154 { 1155 return do_getpgid(pid); 1156 } 1157 1158 #ifdef __ARCH_WANT_SYS_GETPGRP 1159 1160 SYSCALL_DEFINE0(getpgrp) 1161 { 1162 return do_getpgid(0); 1163 } 1164 1165 #endif 1166 1167 SYSCALL_DEFINE1(getsid, pid_t, pid) 1168 { 1169 struct task_struct *p; 1170 struct pid *sid; 1171 int retval; 1172 1173 rcu_read_lock(); 1174 if (!pid) 1175 sid = task_session(current); 1176 else { 1177 retval = -ESRCH; 1178 p = find_task_by_vpid(pid); 1179 if (!p) 1180 goto out; 1181 sid = task_session(p); 1182 if (!sid) 1183 goto out; 1184 1185 retval = security_task_getsid(p); 1186 if (retval) 1187 goto out; 1188 } 1189 retval = pid_vnr(sid); 1190 out: 1191 rcu_read_unlock(); 1192 return retval; 1193 } 1194 1195 static void set_special_pids(struct pid *pid) 1196 { 1197 struct task_struct *curr = current->group_leader; 1198 1199 if (task_session(curr) != pid) 1200 change_pid(curr, PIDTYPE_SID, pid); 1201 1202 if (task_pgrp(curr) != pid) 1203 change_pid(curr, PIDTYPE_PGID, pid); 1204 } 1205 1206 int ksys_setsid(void) 1207 { 1208 struct task_struct *group_leader = current->group_leader; 1209 struct pid *sid = task_pid(group_leader); 1210 pid_t session = pid_vnr(sid); 1211 int err = -EPERM; 1212 1213 write_lock_irq(&tasklist_lock); 1214 /* Fail if I am already a session leader */ 1215 if (group_leader->signal->leader) 1216 goto out; 1217 1218 /* Fail if a process group id already exists that equals the 1219 * proposed session id. 1220 */ 1221 if (pid_task(sid, PIDTYPE_PGID)) 1222 goto out; 1223 1224 group_leader->signal->leader = 1; 1225 set_special_pids(sid); 1226 1227 proc_clear_tty(group_leader); 1228 1229 err = session; 1230 out: 1231 write_unlock_irq(&tasklist_lock); 1232 if (err > 0) { 1233 proc_sid_connector(group_leader); 1234 sched_autogroup_create_attach(group_leader); 1235 } 1236 return err; 1237 } 1238 1239 SYSCALL_DEFINE0(setsid) 1240 { 1241 return ksys_setsid(); 1242 } 1243 1244 DECLARE_RWSEM(uts_sem); 1245 1246 #ifdef COMPAT_UTS_MACHINE 1247 #define override_architecture(name) \ 1248 (personality(current->personality) == PER_LINUX32 && \ 1249 copy_to_user(name->machine, COMPAT_UTS_MACHINE, \ 1250 sizeof(COMPAT_UTS_MACHINE))) 1251 #else 1252 #define override_architecture(name) 0 1253 #endif 1254 1255 /* 1256 * Work around broken programs that cannot handle "Linux 3.0". 1257 * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40 1258 * And we map 4.x and later versions to 2.6.60+x, so 4.0/5.0/6.0/... would be 1259 * 2.6.60. 1260 */ 1261 static int override_release(char __user *release, size_t len) 1262 { 1263 int ret = 0; 1264 1265 if (current->personality & UNAME26) { 1266 const char *rest = UTS_RELEASE; 1267 char buf[65] = { 0 }; 1268 int ndots = 0; 1269 unsigned v; 1270 size_t copy; 1271 1272 while (*rest) { 1273 if (*rest == '.' && ++ndots >= 3) 1274 break; 1275 if (!isdigit(*rest) && *rest != '.') 1276 break; 1277 rest++; 1278 } 1279 v = LINUX_VERSION_PATCHLEVEL + 60; 1280 copy = clamp_t(size_t, len, 1, sizeof(buf)); 1281 copy = scnprintf(buf, copy, "2.6.%u%s", v, rest); 1282 ret = copy_to_user(release, buf, copy + 1); 1283 } 1284 return ret; 1285 } 1286 1287 SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name) 1288 { 1289 struct new_utsname tmp; 1290 1291 down_read(&uts_sem); 1292 memcpy(&tmp, utsname(), sizeof(tmp)); 1293 up_read(&uts_sem); 1294 if (copy_to_user(name, &tmp, sizeof(tmp))) 1295 return -EFAULT; 1296 1297 if (override_release(name->release, sizeof(name->release))) 1298 return -EFAULT; 1299 if (override_architecture(name)) 1300 return -EFAULT; 1301 return 0; 1302 } 1303 1304 #ifdef __ARCH_WANT_SYS_OLD_UNAME 1305 /* 1306 * Old cruft 1307 */ 1308 SYSCALL_DEFINE1(uname, struct old_utsname __user *, name) 1309 { 1310 struct old_utsname tmp; 1311 1312 if (!name) 1313 return -EFAULT; 1314 1315 down_read(&uts_sem); 1316 memcpy(&tmp, utsname(), sizeof(tmp)); 1317 up_read(&uts_sem); 1318 if (copy_to_user(name, &tmp, sizeof(tmp))) 1319 return -EFAULT; 1320 1321 if (override_release(name->release, sizeof(name->release))) 1322 return -EFAULT; 1323 if (override_architecture(name)) 1324 return -EFAULT; 1325 return 0; 1326 } 1327 1328 SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name) 1329 { 1330 struct oldold_utsname tmp; 1331 1332 if (!name) 1333 return -EFAULT; 1334 1335 memset(&tmp, 0, sizeof(tmp)); 1336 1337 down_read(&uts_sem); 1338 memcpy(&tmp.sysname, &utsname()->sysname, __OLD_UTS_LEN); 1339 memcpy(&tmp.nodename, &utsname()->nodename, __OLD_UTS_LEN); 1340 memcpy(&tmp.release, &utsname()->release, __OLD_UTS_LEN); 1341 memcpy(&tmp.version, &utsname()->version, __OLD_UTS_LEN); 1342 memcpy(&tmp.machine, &utsname()->machine, __OLD_UTS_LEN); 1343 up_read(&uts_sem); 1344 if (copy_to_user(name, &tmp, sizeof(tmp))) 1345 return -EFAULT; 1346 1347 if (override_architecture(name)) 1348 return -EFAULT; 1349 if (override_release(name->release, sizeof(name->release))) 1350 return -EFAULT; 1351 return 0; 1352 } 1353 #endif 1354 1355 SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) 1356 { 1357 int errno; 1358 char tmp[__NEW_UTS_LEN]; 1359 1360 if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) 1361 return -EPERM; 1362 1363 if (len < 0 || len > __NEW_UTS_LEN) 1364 return -EINVAL; 1365 errno = -EFAULT; 1366 if (!copy_from_user(tmp, name, len)) { 1367 struct new_utsname *u; 1368 1369 down_write(&uts_sem); 1370 u = utsname(); 1371 memcpy(u->nodename, tmp, len); 1372 memset(u->nodename + len, 0, sizeof(u->nodename) - len); 1373 errno = 0; 1374 uts_proc_notify(UTS_PROC_HOSTNAME); 1375 up_write(&uts_sem); 1376 } 1377 return errno; 1378 } 1379 1380 #ifdef __ARCH_WANT_SYS_GETHOSTNAME 1381 1382 SYSCALL_DEFINE2(gethostname, char __user *, name, int, len) 1383 { 1384 int i; 1385 struct new_utsname *u; 1386 char tmp[__NEW_UTS_LEN + 1]; 1387 1388 if (len < 0) 1389 return -EINVAL; 1390 down_read(&uts_sem); 1391 u = utsname(); 1392 i = 1 + strlen(u->nodename); 1393 if (i > len) 1394 i = len; 1395 memcpy(tmp, u->nodename, i); 1396 up_read(&uts_sem); 1397 if (copy_to_user(name, tmp, i)) 1398 return -EFAULT; 1399 return 0; 1400 } 1401 1402 #endif 1403 1404 /* 1405 * Only setdomainname; getdomainname can be implemented by calling 1406 * uname() 1407 */ 1408 SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) 1409 { 1410 int errno; 1411 char tmp[__NEW_UTS_LEN]; 1412 1413 if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) 1414 return -EPERM; 1415 if (len < 0 || len > __NEW_UTS_LEN) 1416 return -EINVAL; 1417 1418 errno = -EFAULT; 1419 if (!copy_from_user(tmp, name, len)) { 1420 struct new_utsname *u; 1421 1422 down_write(&uts_sem); 1423 u = utsname(); 1424 memcpy(u->domainname, tmp, len); 1425 memset(u->domainname + len, 0, sizeof(u->domainname) - len); 1426 errno = 0; 1427 uts_proc_notify(UTS_PROC_DOMAINNAME); 1428 up_write(&uts_sem); 1429 } 1430 return errno; 1431 } 1432 1433 /* make sure you are allowed to change @tsk limits before calling this */ 1434 static int do_prlimit(struct task_struct *tsk, unsigned int resource, 1435 struct rlimit *new_rlim, struct rlimit *old_rlim) 1436 { 1437 struct rlimit *rlim; 1438 int retval = 0; 1439 1440 if (resource >= RLIM_NLIMITS) 1441 return -EINVAL; 1442 if (new_rlim) { 1443 if (new_rlim->rlim_cur > new_rlim->rlim_max) 1444 return -EINVAL; 1445 if (resource == RLIMIT_NOFILE && 1446 new_rlim->rlim_max > sysctl_nr_open) 1447 return -EPERM; 1448 } 1449 1450 /* Holding a refcount on tsk protects tsk->signal from disappearing. */ 1451 rlim = tsk->signal->rlim + resource; 1452 task_lock(tsk->group_leader); 1453 if (new_rlim) { 1454 /* 1455 * Keep the capable check against init_user_ns until cgroups can 1456 * contain all limits. 1457 */ 1458 if (new_rlim->rlim_max > rlim->rlim_max && 1459 !capable(CAP_SYS_RESOURCE)) 1460 retval = -EPERM; 1461 if (!retval) 1462 retval = security_task_setrlimit(tsk, resource, new_rlim); 1463 } 1464 if (!retval) { 1465 if (old_rlim) 1466 *old_rlim = *rlim; 1467 if (new_rlim) 1468 *rlim = *new_rlim; 1469 } 1470 task_unlock(tsk->group_leader); 1471 1472 /* 1473 * RLIMIT_CPU handling. Arm the posix CPU timer if the limit is not 1474 * infinite. In case of RLIM_INFINITY the posix CPU timer code 1475 * ignores the rlimit. 1476 */ 1477 if (!retval && new_rlim && resource == RLIMIT_CPU && 1478 new_rlim->rlim_cur != RLIM_INFINITY && 1479 IS_ENABLED(CONFIG_POSIX_TIMERS)) { 1480 /* 1481 * update_rlimit_cpu can fail if the task is exiting, but there 1482 * may be other tasks in the thread group that are not exiting, 1483 * and they need their cpu timers adjusted. 1484 * 1485 * The group_leader is the last task to be released, so if we 1486 * cannot update_rlimit_cpu on it, then the entire process is 1487 * exiting and we do not need to update at all. 1488 */ 1489 update_rlimit_cpu(tsk->group_leader, new_rlim->rlim_cur); 1490 } 1491 1492 return retval; 1493 } 1494 1495 SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim) 1496 { 1497 struct rlimit value; 1498 int ret; 1499 1500 ret = do_prlimit(current, resource, NULL, &value); 1501 if (!ret) 1502 ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; 1503 1504 return ret; 1505 } 1506 1507 #ifdef CONFIG_COMPAT 1508 1509 COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource, 1510 struct compat_rlimit __user *, rlim) 1511 { 1512 struct rlimit r; 1513 struct compat_rlimit r32; 1514 1515 if (copy_from_user(&r32, rlim, sizeof(struct compat_rlimit))) 1516 return -EFAULT; 1517 1518 if (r32.rlim_cur == COMPAT_RLIM_INFINITY) 1519 r.rlim_cur = RLIM_INFINITY; 1520 else 1521 r.rlim_cur = r32.rlim_cur; 1522 if (r32.rlim_max == COMPAT_RLIM_INFINITY) 1523 r.rlim_max = RLIM_INFINITY; 1524 else 1525 r.rlim_max = r32.rlim_max; 1526 return do_prlimit(current, resource, &r, NULL); 1527 } 1528 1529 COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource, 1530 struct compat_rlimit __user *, rlim) 1531 { 1532 struct rlimit r; 1533 int ret; 1534 1535 ret = do_prlimit(current, resource, NULL, &r); 1536 if (!ret) { 1537 struct compat_rlimit r32; 1538 if (r.rlim_cur > COMPAT_RLIM_INFINITY) 1539 r32.rlim_cur = COMPAT_RLIM_INFINITY; 1540 else 1541 r32.rlim_cur = r.rlim_cur; 1542 if (r.rlim_max > COMPAT_RLIM_INFINITY) 1543 r32.rlim_max = COMPAT_RLIM_INFINITY; 1544 else 1545 r32.rlim_max = r.rlim_max; 1546 1547 if (copy_to_user(rlim, &r32, sizeof(struct compat_rlimit))) 1548 return -EFAULT; 1549 } 1550 return ret; 1551 } 1552 1553 #endif 1554 1555 #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT 1556 1557 /* 1558 * Back compatibility for getrlimit. Needed for some apps. 1559 */ 1560 SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, 1561 struct rlimit __user *, rlim) 1562 { 1563 struct rlimit x; 1564 if (resource >= RLIM_NLIMITS) 1565 return -EINVAL; 1566 1567 resource = array_index_nospec(resource, RLIM_NLIMITS); 1568 task_lock(current->group_leader); 1569 x = current->signal->rlim[resource]; 1570 task_unlock(current->group_leader); 1571 if (x.rlim_cur > 0x7FFFFFFF) 1572 x.rlim_cur = 0x7FFFFFFF; 1573 if (x.rlim_max > 0x7FFFFFFF) 1574 x.rlim_max = 0x7FFFFFFF; 1575 return copy_to_user(rlim, &x, sizeof(x)) ? -EFAULT : 0; 1576 } 1577 1578 #ifdef CONFIG_COMPAT 1579 COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, 1580 struct compat_rlimit __user *, rlim) 1581 { 1582 struct rlimit r; 1583 1584 if (resource >= RLIM_NLIMITS) 1585 return -EINVAL; 1586 1587 resource = array_index_nospec(resource, RLIM_NLIMITS); 1588 task_lock(current->group_leader); 1589 r = current->signal->rlim[resource]; 1590 task_unlock(current->group_leader); 1591 if (r.rlim_cur > 0x7FFFFFFF) 1592 r.rlim_cur = 0x7FFFFFFF; 1593 if (r.rlim_max > 0x7FFFFFFF) 1594 r.rlim_max = 0x7FFFFFFF; 1595 1596 if (put_user(r.rlim_cur, &rlim->rlim_cur) || 1597 put_user(r.rlim_max, &rlim->rlim_max)) 1598 return -EFAULT; 1599 return 0; 1600 } 1601 #endif 1602 1603 #endif 1604 1605 static inline bool rlim64_is_infinity(__u64 rlim64) 1606 { 1607 #if BITS_PER_LONG < 64 1608 return rlim64 >= ULONG_MAX; 1609 #else 1610 return rlim64 == RLIM64_INFINITY; 1611 #endif 1612 } 1613 1614 static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64) 1615 { 1616 if (rlim->rlim_cur == RLIM_INFINITY) 1617 rlim64->rlim_cur = RLIM64_INFINITY; 1618 else 1619 rlim64->rlim_cur = rlim->rlim_cur; 1620 if (rlim->rlim_max == RLIM_INFINITY) 1621 rlim64->rlim_max = RLIM64_INFINITY; 1622 else 1623 rlim64->rlim_max = rlim->rlim_max; 1624 } 1625 1626 static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim) 1627 { 1628 if (rlim64_is_infinity(rlim64->rlim_cur)) 1629 rlim->rlim_cur = RLIM_INFINITY; 1630 else 1631 rlim->rlim_cur = (unsigned long)rlim64->rlim_cur; 1632 if (rlim64_is_infinity(rlim64->rlim_max)) 1633 rlim->rlim_max = RLIM_INFINITY; 1634 else 1635 rlim->rlim_max = (unsigned long)rlim64->rlim_max; 1636 } 1637 1638 /* rcu lock must be held */ 1639 static int check_prlimit_permission(struct task_struct *task, 1640 unsigned int flags) 1641 { 1642 const struct cred *cred = current_cred(), *tcred; 1643 bool id_match; 1644 1645 if (current == task) 1646 return 0; 1647 1648 tcred = __task_cred(task); 1649 id_match = (uid_eq(cred->uid, tcred->euid) && 1650 uid_eq(cred->uid, tcred->suid) && 1651 uid_eq(cred->uid, tcred->uid) && 1652 gid_eq(cred->gid, tcred->egid) && 1653 gid_eq(cred->gid, tcred->sgid) && 1654 gid_eq(cred->gid, tcred->gid)); 1655 if (!id_match && !ns_capable(tcred->user_ns, CAP_SYS_RESOURCE)) 1656 return -EPERM; 1657 1658 return security_task_prlimit(cred, tcred, flags); 1659 } 1660 1661 SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource, 1662 const struct rlimit64 __user *, new_rlim, 1663 struct rlimit64 __user *, old_rlim) 1664 { 1665 struct rlimit64 old64, new64; 1666 struct rlimit old, new; 1667 struct task_struct *tsk; 1668 unsigned int checkflags = 0; 1669 int ret; 1670 1671 if (old_rlim) 1672 checkflags |= LSM_PRLIMIT_READ; 1673 1674 if (new_rlim) { 1675 if (copy_from_user(&new64, new_rlim, sizeof(new64))) 1676 return -EFAULT; 1677 rlim64_to_rlim(&new64, &new); 1678 checkflags |= LSM_PRLIMIT_WRITE; 1679 } 1680 1681 rcu_read_lock(); 1682 tsk = pid ? find_task_by_vpid(pid) : current; 1683 if (!tsk) { 1684 rcu_read_unlock(); 1685 return -ESRCH; 1686 } 1687 ret = check_prlimit_permission(tsk, checkflags); 1688 if (ret) { 1689 rcu_read_unlock(); 1690 return ret; 1691 } 1692 get_task_struct(tsk); 1693 rcu_read_unlock(); 1694 1695 ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL, 1696 old_rlim ? &old : NULL); 1697 1698 if (!ret && old_rlim) { 1699 rlim_to_rlim64(&old, &old64); 1700 if (copy_to_user(old_rlim, &old64, sizeof(old64))) 1701 ret = -EFAULT; 1702 } 1703 1704 put_task_struct(tsk); 1705 return ret; 1706 } 1707 1708 SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) 1709 { 1710 struct rlimit new_rlim; 1711 1712 if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) 1713 return -EFAULT; 1714 return do_prlimit(current, resource, &new_rlim, NULL); 1715 } 1716 1717 /* 1718 * It would make sense to put struct rusage in the task_struct, 1719 * except that would make the task_struct be *really big*. After 1720 * task_struct gets moved into malloc'ed memory, it would 1721 * make sense to do this. It will make moving the rest of the information 1722 * a lot simpler! (Which we're not doing right now because we're not 1723 * measuring them yet). 1724 * 1725 * When sampling multiple threads for RUSAGE_SELF, under SMP we might have 1726 * races with threads incrementing their own counters. But since word 1727 * reads are atomic, we either get new values or old values and we don't 1728 * care which for the sums. We always take the siglock to protect reading 1729 * the c* fields from p->signal from races with exit.c updating those 1730 * fields when reaping, so a sample either gets all the additions of a 1731 * given child after it's reaped, or none so this sample is before reaping. 1732 * 1733 * Locking: 1734 * We need to take the siglock for CHILDEREN, SELF and BOTH 1735 * for the cases current multithreaded, non-current single threaded 1736 * non-current multithreaded. Thread traversal is now safe with 1737 * the siglock held. 1738 * Strictly speaking, we donot need to take the siglock if we are current and 1739 * single threaded, as no one else can take our signal_struct away, no one 1740 * else can reap the children to update signal->c* counters, and no one else 1741 * can race with the signal-> fields. If we do not take any lock, the 1742 * signal-> fields could be read out of order while another thread was just 1743 * exiting. So we should place a read memory barrier when we avoid the lock. 1744 * On the writer side, write memory barrier is implied in __exit_signal 1745 * as __exit_signal releases the siglock spinlock after updating the signal-> 1746 * fields. But we don't do this yet to keep things simple. 1747 * 1748 */ 1749 1750 static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) 1751 { 1752 r->ru_nvcsw += t->nvcsw; 1753 r->ru_nivcsw += t->nivcsw; 1754 r->ru_minflt += t->min_flt; 1755 r->ru_majflt += t->maj_flt; 1756 r->ru_inblock += task_io_get_inblock(t); 1757 r->ru_oublock += task_io_get_oublock(t); 1758 } 1759 1760 void getrusage(struct task_struct *p, int who, struct rusage *r) 1761 { 1762 struct task_struct *t; 1763 unsigned long flags; 1764 u64 tgutime, tgstime, utime, stime; 1765 unsigned long maxrss = 0; 1766 1767 memset((char *)r, 0, sizeof (*r)); 1768 utime = stime = 0; 1769 1770 if (who == RUSAGE_THREAD) { 1771 task_cputime_adjusted(current, &utime, &stime); 1772 accumulate_thread_rusage(p, r); 1773 maxrss = p->signal->maxrss; 1774 goto out; 1775 } 1776 1777 if (!lock_task_sighand(p, &flags)) 1778 return; 1779 1780 switch (who) { 1781 case RUSAGE_BOTH: 1782 case RUSAGE_CHILDREN: 1783 utime = p->signal->cutime; 1784 stime = p->signal->cstime; 1785 r->ru_nvcsw = p->signal->cnvcsw; 1786 r->ru_nivcsw = p->signal->cnivcsw; 1787 r->ru_minflt = p->signal->cmin_flt; 1788 r->ru_majflt = p->signal->cmaj_flt; 1789 r->ru_inblock = p->signal->cinblock; 1790 r->ru_oublock = p->signal->coublock; 1791 maxrss = p->signal->cmaxrss; 1792 1793 if (who == RUSAGE_CHILDREN) 1794 break; 1795 fallthrough; 1796 1797 case RUSAGE_SELF: 1798 thread_group_cputime_adjusted(p, &tgutime, &tgstime); 1799 utime += tgutime; 1800 stime += tgstime; 1801 r->ru_nvcsw += p->signal->nvcsw; 1802 r->ru_nivcsw += p->signal->nivcsw; 1803 r->ru_minflt += p->signal->min_flt; 1804 r->ru_majflt += p->signal->maj_flt; 1805 r->ru_inblock += p->signal->inblock; 1806 r->ru_oublock += p->signal->oublock; 1807 if (maxrss < p->signal->maxrss) 1808 maxrss = p->signal->maxrss; 1809 t = p; 1810 do { 1811 accumulate_thread_rusage(t, r); 1812 } while_each_thread(p, t); 1813 break; 1814 1815 default: 1816 BUG(); 1817 } 1818 unlock_task_sighand(p, &flags); 1819 1820 out: 1821 r->ru_utime = ns_to_kernel_old_timeval(utime); 1822 r->ru_stime = ns_to_kernel_old_timeval(stime); 1823 1824 if (who != RUSAGE_CHILDREN) { 1825 struct mm_struct *mm = get_task_mm(p); 1826 1827 if (mm) { 1828 setmax_mm_hiwater_rss(&maxrss, mm); 1829 mmput(mm); 1830 } 1831 } 1832 r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */ 1833 } 1834 1835 SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) 1836 { 1837 struct rusage r; 1838 1839 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && 1840 who != RUSAGE_THREAD) 1841 return -EINVAL; 1842 1843 getrusage(current, who, &r); 1844 return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; 1845 } 1846 1847 #ifdef CONFIG_COMPAT 1848 COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru) 1849 { 1850 struct rusage r; 1851 1852 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && 1853 who != RUSAGE_THREAD) 1854 return -EINVAL; 1855 1856 getrusage(current, who, &r); 1857 return put_compat_rusage(&r, ru); 1858 } 1859 #endif 1860 1861 SYSCALL_DEFINE1(umask, int, mask) 1862 { 1863 mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); 1864 return mask; 1865 } 1866 1867 static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd) 1868 { 1869 struct fd exe; 1870 struct inode *inode; 1871 int err; 1872 1873 exe = fdget(fd); 1874 if (!exe.file) 1875 return -EBADF; 1876 1877 inode = file_inode(exe.file); 1878 1879 /* 1880 * Because the original mm->exe_file points to executable file, make 1881 * sure that this one is executable as well, to avoid breaking an 1882 * overall picture. 1883 */ 1884 err = -EACCES; 1885 if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path)) 1886 goto exit; 1887 1888 err = file_permission(exe.file, MAY_EXEC); 1889 if (err) 1890 goto exit; 1891 1892 err = replace_mm_exe_file(mm, exe.file); 1893 exit: 1894 fdput(exe); 1895 return err; 1896 } 1897 1898 /* 1899 * Check arithmetic relations of passed addresses. 1900 * 1901 * WARNING: we don't require any capability here so be very careful 1902 * in what is allowed for modification from userspace. 1903 */ 1904 static int validate_prctl_map_addr(struct prctl_mm_map *prctl_map) 1905 { 1906 unsigned long mmap_max_addr = TASK_SIZE; 1907 int error = -EINVAL, i; 1908 1909 static const unsigned char offsets[] = { 1910 offsetof(struct prctl_mm_map, start_code), 1911 offsetof(struct prctl_mm_map, end_code), 1912 offsetof(struct prctl_mm_map, start_data), 1913 offsetof(struct prctl_mm_map, end_data), 1914 offsetof(struct prctl_mm_map, start_brk), 1915 offsetof(struct prctl_mm_map, brk), 1916 offsetof(struct prctl_mm_map, start_stack), 1917 offsetof(struct prctl_mm_map, arg_start), 1918 offsetof(struct prctl_mm_map, arg_end), 1919 offsetof(struct prctl_mm_map, env_start), 1920 offsetof(struct prctl_mm_map, env_end), 1921 }; 1922 1923 /* 1924 * Make sure the members are not somewhere outside 1925 * of allowed address space. 1926 */ 1927 for (i = 0; i < ARRAY_SIZE(offsets); i++) { 1928 u64 val = *(u64 *)((char *)prctl_map + offsets[i]); 1929 1930 if ((unsigned long)val >= mmap_max_addr || 1931 (unsigned long)val < mmap_min_addr) 1932 goto out; 1933 } 1934 1935 /* 1936 * Make sure the pairs are ordered. 1937 */ 1938 #define __prctl_check_order(__m1, __op, __m2) \ 1939 ((unsigned long)prctl_map->__m1 __op \ 1940 (unsigned long)prctl_map->__m2) ? 0 : -EINVAL 1941 error = __prctl_check_order(start_code, <, end_code); 1942 error |= __prctl_check_order(start_data,<=, end_data); 1943 error |= __prctl_check_order(start_brk, <=, brk); 1944 error |= __prctl_check_order(arg_start, <=, arg_end); 1945 error |= __prctl_check_order(env_start, <=, env_end); 1946 if (error) 1947 goto out; 1948 #undef __prctl_check_order 1949 1950 error = -EINVAL; 1951 1952 /* 1953 * Neither we should allow to override limits if they set. 1954 */ 1955 if (check_data_rlimit(rlimit(RLIMIT_DATA), prctl_map->brk, 1956 prctl_map->start_brk, prctl_map->end_data, 1957 prctl_map->start_data)) 1958 goto out; 1959 1960 error = 0; 1961 out: 1962 return error; 1963 } 1964 1965 #ifdef CONFIG_CHECKPOINT_RESTORE 1966 static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size) 1967 { 1968 struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, }; 1969 unsigned long user_auxv[AT_VECTOR_SIZE]; 1970 struct mm_struct *mm = current->mm; 1971 int error; 1972 1973 BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); 1974 BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256); 1975 1976 if (opt == PR_SET_MM_MAP_SIZE) 1977 return put_user((unsigned int)sizeof(prctl_map), 1978 (unsigned int __user *)addr); 1979 1980 if (data_size != sizeof(prctl_map)) 1981 return -EINVAL; 1982 1983 if (copy_from_user(&prctl_map, addr, sizeof(prctl_map))) 1984 return -EFAULT; 1985 1986 error = validate_prctl_map_addr(&prctl_map); 1987 if (error) 1988 return error; 1989 1990 if (prctl_map.auxv_size) { 1991 /* 1992 * Someone is trying to cheat the auxv vector. 1993 */ 1994 if (!prctl_map.auxv || 1995 prctl_map.auxv_size > sizeof(mm->saved_auxv)) 1996 return -EINVAL; 1997 1998 memset(user_auxv, 0, sizeof(user_auxv)); 1999 if (copy_from_user(user_auxv, 2000 (const void __user *)prctl_map.auxv, 2001 prctl_map.auxv_size)) 2002 return -EFAULT; 2003 2004 /* Last entry must be AT_NULL as specification requires */ 2005 user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL; 2006 user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL; 2007 } 2008 2009 if (prctl_map.exe_fd != (u32)-1) { 2010 /* 2011 * Check if the current user is checkpoint/restore capable. 2012 * At the time of this writing, it checks for CAP_SYS_ADMIN 2013 * or CAP_CHECKPOINT_RESTORE. 2014 * Note that a user with access to ptrace can masquerade an 2015 * arbitrary program as any executable, even setuid ones. 2016 * This may have implications in the tomoyo subsystem. 2017 */ 2018 if (!checkpoint_restore_ns_capable(current_user_ns())) 2019 return -EPERM; 2020 2021 error = prctl_set_mm_exe_file(mm, prctl_map.exe_fd); 2022 if (error) 2023 return error; 2024 } 2025 2026 /* 2027 * arg_lock protects concurrent updates but we still need mmap_lock for 2028 * read to exclude races with sys_brk. 2029 */ 2030 mmap_read_lock(mm); 2031 2032 /* 2033 * We don't validate if these members are pointing to 2034 * real present VMAs because application may have correspond 2035 * VMAs already unmapped and kernel uses these members for statistics 2036 * output in procfs mostly, except 2037 * 2038 * - @start_brk/@brk which are used in do_brk_flags but kernel lookups 2039 * for VMAs when updating these members so anything wrong written 2040 * here cause kernel to swear at userspace program but won't lead 2041 * to any problem in kernel itself 2042 */ 2043 2044 spin_lock(&mm->arg_lock); 2045 mm->start_code = prctl_map.start_code; 2046 mm->end_code = prctl_map.end_code; 2047 mm->start_data = prctl_map.start_data; 2048 mm->end_data = prctl_map.end_data; 2049 mm->start_brk = prctl_map.start_brk; 2050 mm->brk = prctl_map.brk; 2051 mm->start_stack = prctl_map.start_stack; 2052 mm->arg_start = prctl_map.arg_start; 2053 mm->arg_end = prctl_map.arg_end; 2054 mm->env_start = prctl_map.env_start; 2055 mm->env_end = prctl_map.env_end; 2056 spin_unlock(&mm->arg_lock); 2057 2058 /* 2059 * Note this update of @saved_auxv is lockless thus 2060 * if someone reads this member in procfs while we're 2061 * updating -- it may get partly updated results. It's 2062 * known and acceptable trade off: we leave it as is to 2063 * not introduce additional locks here making the kernel 2064 * more complex. 2065 */ 2066 if (prctl_map.auxv_size) 2067 memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv)); 2068 2069 mmap_read_unlock(mm); 2070 return 0; 2071 } 2072 #endif /* CONFIG_CHECKPOINT_RESTORE */ 2073 2074 static int prctl_set_auxv(struct mm_struct *mm, unsigned long addr, 2075 unsigned long len) 2076 { 2077 /* 2078 * This doesn't move the auxiliary vector itself since it's pinned to 2079 * mm_struct, but it permits filling the vector with new values. It's 2080 * up to the caller to provide sane values here, otherwise userspace 2081 * tools which use this vector might be unhappy. 2082 */ 2083 unsigned long user_auxv[AT_VECTOR_SIZE] = {}; 2084 2085 if (len > sizeof(user_auxv)) 2086 return -EINVAL; 2087 2088 if (copy_from_user(user_auxv, (const void __user *)addr, len)) 2089 return -EFAULT; 2090 2091 /* Make sure the last entry is always AT_NULL */ 2092 user_auxv[AT_VECTOR_SIZE - 2] = 0; 2093 user_auxv[AT_VECTOR_SIZE - 1] = 0; 2094 2095 BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); 2096 2097 task_lock(current); 2098 memcpy(mm->saved_auxv, user_auxv, len); 2099 task_unlock(current); 2100 2101 return 0; 2102 } 2103 2104 static int prctl_set_mm(int opt, unsigned long addr, 2105 unsigned long arg4, unsigned long arg5) 2106 { 2107 struct mm_struct *mm = current->mm; 2108 struct prctl_mm_map prctl_map = { 2109 .auxv = NULL, 2110 .auxv_size = 0, 2111 .exe_fd = -1, 2112 }; 2113 struct vm_area_struct *vma; 2114 int error; 2115 2116 if (arg5 || (arg4 && (opt != PR_SET_MM_AUXV && 2117 opt != PR_SET_MM_MAP && 2118 opt != PR_SET_MM_MAP_SIZE))) 2119 return -EINVAL; 2120 2121 #ifdef CONFIG_CHECKPOINT_RESTORE 2122 if (opt == PR_SET_MM_MAP || opt == PR_SET_MM_MAP_SIZE) 2123 return prctl_set_mm_map(opt, (const void __user *)addr, arg4); 2124 #endif 2125 2126 if (!capable(CAP_SYS_RESOURCE)) 2127 return -EPERM; 2128 2129 if (opt == PR_SET_MM_EXE_FILE) 2130 return prctl_set_mm_exe_file(mm, (unsigned int)addr); 2131 2132 if (opt == PR_SET_MM_AUXV) 2133 return prctl_set_auxv(mm, addr, arg4); 2134 2135 if (addr >= TASK_SIZE || addr < mmap_min_addr) 2136 return -EINVAL; 2137 2138 error = -EINVAL; 2139 2140 /* 2141 * arg_lock protects concurrent updates of arg boundaries, we need 2142 * mmap_lock for a) concurrent sys_brk, b) finding VMA for addr 2143 * validation. 2144 */ 2145 mmap_read_lock(mm); 2146 vma = find_vma(mm, addr); 2147 2148 spin_lock(&mm->arg_lock); 2149 prctl_map.start_code = mm->start_code; 2150 prctl_map.end_code = mm->end_code; 2151 prctl_map.start_data = mm->start_data; 2152 prctl_map.end_data = mm->end_data; 2153 prctl_map.start_brk = mm->start_brk; 2154 prctl_map.brk = mm->brk; 2155 prctl_map.start_stack = mm->start_stack; 2156 prctl_map.arg_start = mm->arg_start; 2157 prctl_map.arg_end = mm->arg_end; 2158 prctl_map.env_start = mm->env_start; 2159 prctl_map.env_end = mm->env_end; 2160 2161 switch (opt) { 2162 case PR_SET_MM_START_CODE: 2163 prctl_map.start_code = addr; 2164 break; 2165 case PR_SET_MM_END_CODE: 2166 prctl_map.end_code = addr; 2167 break; 2168 case PR_SET_MM_START_DATA: 2169 prctl_map.start_data = addr; 2170 break; 2171 case PR_SET_MM_END_DATA: 2172 prctl_map.end_data = addr; 2173 break; 2174 case PR_SET_MM_START_STACK: 2175 prctl_map.start_stack = addr; 2176 break; 2177 case PR_SET_MM_START_BRK: 2178 prctl_map.start_brk = addr; 2179 break; 2180 case PR_SET_MM_BRK: 2181 prctl_map.brk = addr; 2182 break; 2183 case PR_SET_MM_ARG_START: 2184 prctl_map.arg_start = addr; 2185 break; 2186 case PR_SET_MM_ARG_END: 2187 prctl_map.arg_end = addr; 2188 break; 2189 case PR_SET_MM_ENV_START: 2190 prctl_map.env_start = addr; 2191 break; 2192 case PR_SET_MM_ENV_END: 2193 prctl_map.env_end = addr; 2194 break; 2195 default: 2196 goto out; 2197 } 2198 2199 error = validate_prctl_map_addr(&prctl_map); 2200 if (error) 2201 goto out; 2202 2203 switch (opt) { 2204 /* 2205 * If command line arguments and environment 2206 * are placed somewhere else on stack, we can 2207 * set them up here, ARG_START/END to setup 2208 * command line arguments and ENV_START/END 2209 * for environment. 2210 */ 2211 case PR_SET_MM_START_STACK: 2212 case PR_SET_MM_ARG_START: 2213 case PR_SET_MM_ARG_END: 2214 case PR_SET_MM_ENV_START: 2215 case PR_SET_MM_ENV_END: 2216 if (!vma) { 2217 error = -EFAULT; 2218 goto out; 2219 } 2220 } 2221 2222 mm->start_code = prctl_map.start_code; 2223 mm->end_code = prctl_map.end_code; 2224 mm->start_data = prctl_map.start_data; 2225 mm->end_data = prctl_map.end_data; 2226 mm->start_brk = prctl_map.start_brk; 2227 mm->brk = prctl_map.brk; 2228 mm->start_stack = prctl_map.start_stack; 2229 mm->arg_start = prctl_map.arg_start; 2230 mm->arg_end = prctl_map.arg_end; 2231 mm->env_start = prctl_map.env_start; 2232 mm->env_end = prctl_map.env_end; 2233 2234 error = 0; 2235 out: 2236 spin_unlock(&mm->arg_lock); 2237 mmap_read_unlock(mm); 2238 return error; 2239 } 2240 2241 #ifdef CONFIG_CHECKPOINT_RESTORE 2242 static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr) 2243 { 2244 return put_user(me->clear_child_tid, tid_addr); 2245 } 2246 #else 2247 static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr) 2248 { 2249 return -EINVAL; 2250 } 2251 #endif 2252 2253 static int propagate_has_child_subreaper(struct task_struct *p, void *data) 2254 { 2255 /* 2256 * If task has has_child_subreaper - all its descendants 2257 * already have these flag too and new descendants will 2258 * inherit it on fork, skip them. 2259 * 2260 * If we've found child_reaper - skip descendants in 2261 * it's subtree as they will never get out pidns. 2262 */ 2263 if (p->signal->has_child_subreaper || 2264 is_child_reaper(task_pid(p))) 2265 return 0; 2266 2267 p->signal->has_child_subreaper = 1; 2268 return 1; 2269 } 2270 2271 int __weak arch_prctl_spec_ctrl_get(struct task_struct *t, unsigned long which) 2272 { 2273 return -EINVAL; 2274 } 2275 2276 int __weak arch_prctl_spec_ctrl_set(struct task_struct *t, unsigned long which, 2277 unsigned long ctrl) 2278 { 2279 return -EINVAL; 2280 } 2281 2282 #define PR_IO_FLUSHER (PF_MEMALLOC_NOIO | PF_LOCAL_THROTTLE) 2283 2284 #ifdef CONFIG_ANON_VMA_NAME 2285 2286 #define ANON_VMA_NAME_MAX_LEN 80 2287 #define ANON_VMA_NAME_INVALID_CHARS "\\`$[]" 2288 2289 static inline bool is_valid_name_char(char ch) 2290 { 2291 /* printable ascii characters, excluding ANON_VMA_NAME_INVALID_CHARS */ 2292 return ch > 0x1f && ch < 0x7f && 2293 !strchr(ANON_VMA_NAME_INVALID_CHARS, ch); 2294 } 2295 2296 static int prctl_set_vma(unsigned long opt, unsigned long addr, 2297 unsigned long size, unsigned long arg) 2298 { 2299 struct mm_struct *mm = current->mm; 2300 const char __user *uname; 2301 struct anon_vma_name *anon_name = NULL; 2302 int error; 2303 2304 switch (opt) { 2305 case PR_SET_VMA_ANON_NAME: 2306 uname = (const char __user *)arg; 2307 if (uname) { 2308 char *name, *pch; 2309 2310 name = strndup_user(uname, ANON_VMA_NAME_MAX_LEN); 2311 if (IS_ERR(name)) 2312 return PTR_ERR(name); 2313 2314 for (pch = name; *pch != '\0'; pch++) { 2315 if (!is_valid_name_char(*pch)) { 2316 kfree(name); 2317 return -EINVAL; 2318 } 2319 } 2320 /* anon_vma has its own copy */ 2321 anon_name = anon_vma_name_alloc(name); 2322 kfree(name); 2323 if (!anon_name) 2324 return -ENOMEM; 2325 2326 } 2327 2328 mmap_write_lock(mm); 2329 error = madvise_set_anon_name(mm, addr, size, anon_name); 2330 mmap_write_unlock(mm); 2331 anon_vma_name_put(anon_name); 2332 break; 2333 default: 2334 error = -EINVAL; 2335 } 2336 2337 return error; 2338 } 2339 2340 #else /* CONFIG_ANON_VMA_NAME */ 2341 static int prctl_set_vma(unsigned long opt, unsigned long start, 2342 unsigned long size, unsigned long arg) 2343 { 2344 return -EINVAL; 2345 } 2346 #endif /* CONFIG_ANON_VMA_NAME */ 2347 2348 SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, 2349 unsigned long, arg4, unsigned long, arg5) 2350 { 2351 struct task_struct *me = current; 2352 unsigned char comm[sizeof(me->comm)]; 2353 long error; 2354 2355 error = security_task_prctl(option, arg2, arg3, arg4, arg5); 2356 if (error != -ENOSYS) 2357 return error; 2358 2359 error = 0; 2360 switch (option) { 2361 case PR_SET_PDEATHSIG: 2362 if (!valid_signal(arg2)) { 2363 error = -EINVAL; 2364 break; 2365 } 2366 me->pdeath_signal = arg2; 2367 break; 2368 case PR_GET_PDEATHSIG: 2369 error = put_user(me->pdeath_signal, (int __user *)arg2); 2370 break; 2371 case PR_GET_DUMPABLE: 2372 error = get_dumpable(me->mm); 2373 break; 2374 case PR_SET_DUMPABLE: 2375 if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) { 2376 error = -EINVAL; 2377 break; 2378 } 2379 set_dumpable(me->mm, arg2); 2380 break; 2381 2382 case PR_SET_UNALIGN: 2383 error = SET_UNALIGN_CTL(me, arg2); 2384 break; 2385 case PR_GET_UNALIGN: 2386 error = GET_UNALIGN_CTL(me, arg2); 2387 break; 2388 case PR_SET_FPEMU: 2389 error = SET_FPEMU_CTL(me, arg2); 2390 break; 2391 case PR_GET_FPEMU: 2392 error = GET_FPEMU_CTL(me, arg2); 2393 break; 2394 case PR_SET_FPEXC: 2395 error = SET_FPEXC_CTL(me, arg2); 2396 break; 2397 case PR_GET_FPEXC: 2398 error = GET_FPEXC_CTL(me, arg2); 2399 break; 2400 case PR_GET_TIMING: 2401 error = PR_TIMING_STATISTICAL; 2402 break; 2403 case PR_SET_TIMING: 2404 if (arg2 != PR_TIMING_STATISTICAL) 2405 error = -EINVAL; 2406 break; 2407 case PR_SET_NAME: 2408 comm[sizeof(me->comm) - 1] = 0; 2409 if (strncpy_from_user(comm, (char __user *)arg2, 2410 sizeof(me->comm) - 1) < 0) 2411 return -EFAULT; 2412 set_task_comm(me, comm); 2413 proc_comm_connector(me); 2414 break; 2415 case PR_GET_NAME: 2416 get_task_comm(comm, me); 2417 if (copy_to_user((char __user *)arg2, comm, sizeof(comm))) 2418 return -EFAULT; 2419 break; 2420 case PR_GET_ENDIAN: 2421 error = GET_ENDIAN(me, arg2); 2422 break; 2423 case PR_SET_ENDIAN: 2424 error = SET_ENDIAN(me, arg2); 2425 break; 2426 case PR_GET_SECCOMP: 2427 error = prctl_get_seccomp(); 2428 break; 2429 case PR_SET_SECCOMP: 2430 error = prctl_set_seccomp(arg2, (char __user *)arg3); 2431 break; 2432 case PR_GET_TSC: 2433 error = GET_TSC_CTL(arg2); 2434 break; 2435 case PR_SET_TSC: 2436 error = SET_TSC_CTL(arg2); 2437 break; 2438 case PR_TASK_PERF_EVENTS_DISABLE: 2439 error = perf_event_task_disable(); 2440 break; 2441 case PR_TASK_PERF_EVENTS_ENABLE: 2442 error = perf_event_task_enable(); 2443 break; 2444 case PR_GET_TIMERSLACK: 2445 if (current->timer_slack_ns > ULONG_MAX) 2446 error = ULONG_MAX; 2447 else 2448 error = current->timer_slack_ns; 2449 break; 2450 case PR_SET_TIMERSLACK: 2451 if (arg2 <= 0) 2452 current->timer_slack_ns = 2453 current->default_timer_slack_ns; 2454 else 2455 current->timer_slack_ns = arg2; 2456 break; 2457 case PR_MCE_KILL: 2458 if (arg4 | arg5) 2459 return -EINVAL; 2460 switch (arg2) { 2461 case PR_MCE_KILL_CLEAR: 2462 if (arg3 != 0) 2463 return -EINVAL; 2464 current->flags &= ~PF_MCE_PROCESS; 2465 break; 2466 case PR_MCE_KILL_SET: 2467 current->flags |= PF_MCE_PROCESS; 2468 if (arg3 == PR_MCE_KILL_EARLY) 2469 current->flags |= PF_MCE_EARLY; 2470 else if (arg3 == PR_MCE_KILL_LATE) 2471 current->flags &= ~PF_MCE_EARLY; 2472 else if (arg3 == PR_MCE_KILL_DEFAULT) 2473 current->flags &= 2474 ~(PF_MCE_EARLY|PF_MCE_PROCESS); 2475 else 2476 return -EINVAL; 2477 break; 2478 default: 2479 return -EINVAL; 2480 } 2481 break; 2482 case PR_MCE_KILL_GET: 2483 if (arg2 | arg3 | arg4 | arg5) 2484 return -EINVAL; 2485 if (current->flags & PF_MCE_PROCESS) 2486 error = (current->flags & PF_MCE_EARLY) ? 2487 PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE; 2488 else 2489 error = PR_MCE_KILL_DEFAULT; 2490 break; 2491 case PR_SET_MM: 2492 error = prctl_set_mm(arg2, arg3, arg4, arg5); 2493 break; 2494 case PR_GET_TID_ADDRESS: 2495 error = prctl_get_tid_address(me, (int __user * __user *)arg2); 2496 break; 2497 case PR_SET_CHILD_SUBREAPER: 2498 me->signal->is_child_subreaper = !!arg2; 2499 if (!arg2) 2500 break; 2501 2502 walk_process_tree(me, propagate_has_child_subreaper, NULL); 2503 break; 2504 case PR_GET_CHILD_SUBREAPER: 2505 error = put_user(me->signal->is_child_subreaper, 2506 (int __user *)arg2); 2507 break; 2508 case PR_SET_NO_NEW_PRIVS: 2509 if (arg2 != 1 || arg3 || arg4 || arg5) 2510 return -EINVAL; 2511 2512 task_set_no_new_privs(current); 2513 break; 2514 case PR_GET_NO_NEW_PRIVS: 2515 if (arg2 || arg3 || arg4 || arg5) 2516 return -EINVAL; 2517 return task_no_new_privs(current) ? 1 : 0; 2518 case PR_GET_THP_DISABLE: 2519 if (arg2 || arg3 || arg4 || arg5) 2520 return -EINVAL; 2521 error = !!test_bit(MMF_DISABLE_THP, &me->mm->flags); 2522 break; 2523 case PR_SET_THP_DISABLE: 2524 if (arg3 || arg4 || arg5) 2525 return -EINVAL; 2526 if (mmap_write_lock_killable(me->mm)) 2527 return -EINTR; 2528 if (arg2) 2529 set_bit(MMF_DISABLE_THP, &me->mm->flags); 2530 else 2531 clear_bit(MMF_DISABLE_THP, &me->mm->flags); 2532 mmap_write_unlock(me->mm); 2533 break; 2534 case PR_MPX_ENABLE_MANAGEMENT: 2535 case PR_MPX_DISABLE_MANAGEMENT: 2536 /* No longer implemented: */ 2537 return -EINVAL; 2538 case PR_SET_FP_MODE: 2539 error = SET_FP_MODE(me, arg2); 2540 break; 2541 case PR_GET_FP_MODE: 2542 error = GET_FP_MODE(me); 2543 break; 2544 case PR_SVE_SET_VL: 2545 error = SVE_SET_VL(arg2); 2546 break; 2547 case PR_SVE_GET_VL: 2548 error = SVE_GET_VL(); 2549 break; 2550 case PR_SME_SET_VL: 2551 error = SME_SET_VL(arg2); 2552 break; 2553 case PR_SME_GET_VL: 2554 error = SME_GET_VL(); 2555 break; 2556 case PR_GET_SPECULATION_CTRL: 2557 if (arg3 || arg4 || arg5) 2558 return -EINVAL; 2559 error = arch_prctl_spec_ctrl_get(me, arg2); 2560 break; 2561 case PR_SET_SPECULATION_CTRL: 2562 if (arg4 || arg5) 2563 return -EINVAL; 2564 error = arch_prctl_spec_ctrl_set(me, arg2, arg3); 2565 break; 2566 case PR_PAC_RESET_KEYS: 2567 if (arg3 || arg4 || arg5) 2568 return -EINVAL; 2569 error = PAC_RESET_KEYS(me, arg2); 2570 break; 2571 case PR_PAC_SET_ENABLED_KEYS: 2572 if (arg4 || arg5) 2573 return -EINVAL; 2574 error = PAC_SET_ENABLED_KEYS(me, arg2, arg3); 2575 break; 2576 case PR_PAC_GET_ENABLED_KEYS: 2577 if (arg2 || arg3 || arg4 || arg5) 2578 return -EINVAL; 2579 error = PAC_GET_ENABLED_KEYS(me); 2580 break; 2581 case PR_SET_TAGGED_ADDR_CTRL: 2582 if (arg3 || arg4 || arg5) 2583 return -EINVAL; 2584 error = SET_TAGGED_ADDR_CTRL(arg2); 2585 break; 2586 case PR_GET_TAGGED_ADDR_CTRL: 2587 if (arg2 || arg3 || arg4 || arg5) 2588 return -EINVAL; 2589 error = GET_TAGGED_ADDR_CTRL(); 2590 break; 2591 case PR_SET_IO_FLUSHER: 2592 if (!capable(CAP_SYS_RESOURCE)) 2593 return -EPERM; 2594 2595 if (arg3 || arg4 || arg5) 2596 return -EINVAL; 2597 2598 if (arg2 == 1) 2599 current->flags |= PR_IO_FLUSHER; 2600 else if (!arg2) 2601 current->flags &= ~PR_IO_FLUSHER; 2602 else 2603 return -EINVAL; 2604 break; 2605 case PR_GET_IO_FLUSHER: 2606 if (!capable(CAP_SYS_RESOURCE)) 2607 return -EPERM; 2608 2609 if (arg2 || arg3 || arg4 || arg5) 2610 return -EINVAL; 2611 2612 error = (current->flags & PR_IO_FLUSHER) == PR_IO_FLUSHER; 2613 break; 2614 case PR_SET_SYSCALL_USER_DISPATCH: 2615 error = set_syscall_user_dispatch(arg2, arg3, arg4, 2616 (char __user *) arg5); 2617 break; 2618 #ifdef CONFIG_SCHED_CORE 2619 case PR_SCHED_CORE: 2620 error = sched_core_share_pid(arg2, arg3, arg4, arg5); 2621 break; 2622 #endif 2623 case PR_SET_VMA: 2624 error = prctl_set_vma(arg2, arg3, arg4, arg5); 2625 break; 2626 default: 2627 error = -EINVAL; 2628 break; 2629 } 2630 return error; 2631 } 2632 2633 SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep, 2634 struct getcpu_cache __user *, unused) 2635 { 2636 int err = 0; 2637 int cpu = raw_smp_processor_id(); 2638 2639 if (cpup) 2640 err |= put_user(cpu, cpup); 2641 if (nodep) 2642 err |= put_user(cpu_to_node(cpu), nodep); 2643 return err ? -EFAULT : 0; 2644 } 2645 2646 /** 2647 * do_sysinfo - fill in sysinfo struct 2648 * @info: pointer to buffer to fill 2649 */ 2650 static int do_sysinfo(struct sysinfo *info) 2651 { 2652 unsigned long mem_total, sav_total; 2653 unsigned int mem_unit, bitcount; 2654 struct timespec64 tp; 2655 2656 memset(info, 0, sizeof(struct sysinfo)); 2657 2658 ktime_get_boottime_ts64(&tp); 2659 timens_add_boottime(&tp); 2660 info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0); 2661 2662 get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT); 2663 2664 info->procs = nr_threads; 2665 2666 si_meminfo(info); 2667 si_swapinfo(info); 2668 2669 /* 2670 * If the sum of all the available memory (i.e. ram + swap) 2671 * is less than can be stored in a 32 bit unsigned long then 2672 * we can be binary compatible with 2.2.x kernels. If not, 2673 * well, in that case 2.2.x was broken anyways... 2674 * 2675 * -Erik Andersen <andersee@debian.org> 2676 */ 2677 2678 mem_total = info->totalram + info->totalswap; 2679 if (mem_total < info->totalram || mem_total < info->totalswap) 2680 goto out; 2681 bitcount = 0; 2682 mem_unit = info->mem_unit; 2683 while (mem_unit > 1) { 2684 bitcount++; 2685 mem_unit >>= 1; 2686 sav_total = mem_total; 2687 mem_total <<= 1; 2688 if (mem_total < sav_total) 2689 goto out; 2690 } 2691 2692 /* 2693 * If mem_total did not overflow, multiply all memory values by 2694 * info->mem_unit and set it to 1. This leaves things compatible 2695 * with 2.2.x, and also retains compatibility with earlier 2.4.x 2696 * kernels... 2697 */ 2698 2699 info->mem_unit = 1; 2700 info->totalram <<= bitcount; 2701 info->freeram <<= bitcount; 2702 info->sharedram <<= bitcount; 2703 info->bufferram <<= bitcount; 2704 info->totalswap <<= bitcount; 2705 info->freeswap <<= bitcount; 2706 info->totalhigh <<= bitcount; 2707 info->freehigh <<= bitcount; 2708 2709 out: 2710 return 0; 2711 } 2712 2713 SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info) 2714 { 2715 struct sysinfo val; 2716 2717 do_sysinfo(&val); 2718 2719 if (copy_to_user(info, &val, sizeof(struct sysinfo))) 2720 return -EFAULT; 2721 2722 return 0; 2723 } 2724 2725 #ifdef CONFIG_COMPAT 2726 struct compat_sysinfo { 2727 s32 uptime; 2728 u32 loads[3]; 2729 u32 totalram; 2730 u32 freeram; 2731 u32 sharedram; 2732 u32 bufferram; 2733 u32 totalswap; 2734 u32 freeswap; 2735 u16 procs; 2736 u16 pad; 2737 u32 totalhigh; 2738 u32 freehigh; 2739 u32 mem_unit; 2740 char _f[20-2*sizeof(u32)-sizeof(int)]; 2741 }; 2742 2743 COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info) 2744 { 2745 struct sysinfo s; 2746 struct compat_sysinfo s_32; 2747 2748 do_sysinfo(&s); 2749 2750 /* Check to see if any memory value is too large for 32-bit and scale 2751 * down if needed 2752 */ 2753 if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) { 2754 int bitcount = 0; 2755 2756 while (s.mem_unit < PAGE_SIZE) { 2757 s.mem_unit <<= 1; 2758 bitcount++; 2759 } 2760 2761 s.totalram >>= bitcount; 2762 s.freeram >>= bitcount; 2763 s.sharedram >>= bitcount; 2764 s.bufferram >>= bitcount; 2765 s.totalswap >>= bitcount; 2766 s.freeswap >>= bitcount; 2767 s.totalhigh >>= bitcount; 2768 s.freehigh >>= bitcount; 2769 } 2770 2771 memset(&s_32, 0, sizeof(s_32)); 2772 s_32.uptime = s.uptime; 2773 s_32.loads[0] = s.loads[0]; 2774 s_32.loads[1] = s.loads[1]; 2775 s_32.loads[2] = s.loads[2]; 2776 s_32.totalram = s.totalram; 2777 s_32.freeram = s.freeram; 2778 s_32.sharedram = s.sharedram; 2779 s_32.bufferram = s.bufferram; 2780 s_32.totalswap = s.totalswap; 2781 s_32.freeswap = s.freeswap; 2782 s_32.procs = s.procs; 2783 s_32.totalhigh = s.totalhigh; 2784 s_32.freehigh = s.freehigh; 2785 s_32.mem_unit = s.mem_unit; 2786 if (copy_to_user(info, &s_32, sizeof(s_32))) 2787 return -EFAULT; 2788 return 0; 2789 } 2790 #endif /* CONFIG_COMPAT */ 2791