root/kernel/sys.c

/* */

DEFINITIONS

1. sys_ni_syscall
2. proc_sel
3. sys_setpriority
4. sys_getpriority
5. sys_profil
6. sys_ftime
7. sys_break
8. sys_stty
9. sys_gtty
10. sys_prof
11. sys_reboot
12. ctrl_alt_del
13. sys_setregid
14. sys_setgid
15. sys_acct
16. sys_phys
17. sys_lock
18. sys_mpx
19. sys_ulimit
20. sys_old_syscall
21. sys_setreuid
22. sys_setuid
23. sys_setfsuid
24. sys_setfsgid
25. sys_times
26. sys_brk
27. sys_setpgid
28. sys_getpgid
29. sys_getpgrp
30. sys_setsid
31. sys_getgroups
32. sys_setgroups
33. in_group_p
34. sys_newuname
35. sys_uname
36. sys_olduname
37. sys_sethostname
38. sys_setdomainname
39. sys_getrlimit
40. sys_setrlimit
41. getrusage
42. sys_getrusage
43. sys_umask

   1 /*
   2  *  linux/kernel/sys.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  */
   6 
   7 #include <linux/errno.h>
   8 #include <linux/sched.h>
   9 #include <linux/kernel.h>
  10 #include <linux/times.h>
  11 #include <linux/utsname.h>
  12 #include <linux/param.h>
  13 #include <linux/resource.h>
  14 #include <linux/signal.h>
  15 #include <linux/string.h>
  16 #include <linux/ptrace.h>
  17 #include <linux/stat.h>
  18 #include <linux/mman.h>
  19 #include <linux/mm.h>
  20 
  21 #include <asm/segment.h>
  22 #include <asm/io.h>
  23 
  24 /*
  25  * this indicates whether you can reboot with ctrl-alt-del: the default is yes
  26  */
  27 static int C_A_D = 1;
  28 
  29 extern void adjust_clock(void);
  30 
  31 #define PZERO   15
  32 
  33 asmlinkage int sys_ni_syscall(void)
     /*  */
  34 {
  35         return -ENOSYS;
  36 }
  37 
  38 static int proc_sel(struct task_struct *p, int which, int who)
     /*  */
  39 {
  40         switch (which) {
  41                 case PRIO_PROCESS:
  42                         if (!who && p == current)
  43                                 return 1;
  44                         return(p->pid == who);
  45                 case PRIO_PGRP:
  46                         if (!who)
  47                                 who = current->pgrp;
  48                         return(p->pgrp == who);
  49                 case PRIO_USER:
  50                         if (!who)
  51                                 who = current->uid;
  52                         return(p->uid == who);
  53         }
  54         return 0;
  55 }
  56 
  57 asmlinkage int sys_setpriority(int which, int who, int niceval)
     /*  */
  58 {
  59         struct task_struct **p;
  60         int error = ESRCH;
  61         int priority;
  62 
  63         if (which > 2 || which < 0)
  64                 return -EINVAL;
  65 
  66         if ((priority = PZERO - niceval) <= 0)
  67                 priority = 1;
  68 
  69         for(p = &LAST_TASK; p > &FIRST_TASK; --p) {
  70                 if (!*p || !proc_sel(*p, which, who))
  71                         continue;
  72                 if ((*p)->uid != current->euid &&
  73                         (*p)->uid != current->uid && !suser()) {
  74                         error = EPERM;
  75                         continue;
  76                 }
  77                 if (error == ESRCH)
  78                         error = 0;
  79                 if (priority > (*p)->priority && !suser())
  80                         error = EACCES;
  81                 else
  82                         (*p)->priority = priority;
  83         }
  84         return -error;
  85 }
  86 
  87 asmlinkage int sys_getpriority(int which, int who)
     /*  */
  88 {
  89         struct task_struct **p;
  90         int max_prio = 0;
  91 
  92         if (which > 2 || which < 0)
  93                 return -EINVAL;
  94 
  95         for(p = &LAST_TASK; p > &FIRST_TASK; --p) {
  96                 if (!*p || !proc_sel(*p, which, who))
  97                         continue;
  98                 if ((*p)->priority > max_prio)
  99                         max_prio = (*p)->priority;
 100         }
 101         return(max_prio ? max_prio : -ESRCH);
 102 }
 103 
 104 asmlinkage int sys_profil(void)
     /*  */
 105 {
 106         return -ENOSYS;
 107 }
 108 
 109 asmlinkage int sys_ftime(void)
     /*  */
 110 {
 111         return -ENOSYS;
 112 }
 113 
 114 asmlinkage int sys_break(void)
     /*  */
 115 {
 116         return -ENOSYS;
 117 }
 118 
 119 asmlinkage int sys_stty(void)
     /*  */
 120 {
 121         return -ENOSYS;
 122 }
 123 
 124 asmlinkage int sys_gtty(void)
     /*  */
 125 {
 126         return -ENOSYS;
 127 }
 128 
 129 asmlinkage int sys_prof(void)
     /*  */
 130 {
 131         return -ENOSYS;
 132 }
 133 
 134 extern void hard_reset_now(void);
 135 extern asmlinkage sys_kill(int, int);
 136 
 137 /*
 138  * Reboot system call: for obvious reasons only root may call it,
 139  * and even root needs to set up some magic numbers in the registers
 140  * so that some mistake won't make this reboot the whole machine.
 141  * You can also set the meaning of the ctrl-alt-del-key here.
 142  *
 143  * reboot doesn't sync: do that yourself before calling this.
 144  */
 145 asmlinkage int sys_reboot(int magic, int magic_too, int flag)
     /*  */
 146 {
 147         if (!suser())
 148                 return -EPERM;
 149         if (magic != 0xfee1dead || magic_too != 672274793)
 150                 return -EINVAL;
 151         if (flag == 0x01234567)
 152                 hard_reset_now();
 153         else if (flag == 0x89ABCDEF)
 154                 C_A_D = 1;
 155         else if (!flag)
 156                 C_A_D = 0;
 157         else if (flag == 0xCDEF0123) {
 158                 printk(KERN_EMERG "System halted\n");
 159                 sys_kill(-1, SIGKILL);
 160                 do_exit(0);
 161         } else
 162                 return -EINVAL;
 163         return (0);
 164 }
 165 
 166 /*
 167  * This function gets called by ctrl-alt-del - ie the keyboard interrupt.
 168  * As it's called within an interrupt, it may NOT sync: the only choice
 169  * is whether to reboot at once, or just ignore the ctrl-alt-del.
 170  */
 171 void ctrl_alt_del(void)
     /*  */
 172 {
 173         if (C_A_D)
 174                 hard_reset_now();
 175         else
 176                 send_sig(SIGINT,task[1],1);
 177 }
 178         
 179 
 180 /*
 181  * Unprivileged users may change the real gid to the effective gid
 182  * or vice versa.  (BSD-style)
 183  *
 184  * If you set the real gid at all, or set the effective gid to a value not
 185  * equal to the real gid, then the saved gid is set to the new effective gid.
 186  *
 187  * This makes it possible for a setgid program to completely drop its
 188  * privileges, which is often a useful assertion to make when you are doing
 189  * a security audit over a program.
 190  *
 191  * The general idea is that a program which uses just setregid() will be
 192  * 100% compatible with BSD.  A program which uses just setgid() will be
 193  * 100% compatible with POSIX w/ Saved ID's. 
 194  */
 195 asmlinkage int sys_setregid(gid_t rgid, gid_t egid)
     /*  */
 196 {
 197         int old_rgid = current->gid;
 198 
 199         if (rgid != (gid_t) -1) {
 200                 if ((old_rgid == rgid) ||
 201                     (current->egid==rgid) ||
 202                     suser())
 203                         current->gid = rgid;
 204                 else
 205                         return(-EPERM);
 206         }
 207         if (egid != (gid_t) -1) {
 208                 if ((old_rgid == egid) ||
 209                     (current->egid == egid) ||
 210                     (current->sgid == egid) ||
 211                     suser())
 212                         current->egid = egid;
 213                 else {
 214                         current->gid = old_rgid;
 215                         return(-EPERM);
 216                 }
 217         }
 218         if (rgid != (gid_t) -1 ||
 219             (egid != (gid_t) -1 && egid != old_rgid))
 220                 current->sgid = current->egid;
 221         current->fsgid = current->egid;
 222         return 0;
 223 }
 224 
 225 /*
 226  * setgid() is implemented like SysV w/ SAVED_IDS 
 227  */
 228 asmlinkage int sys_setgid(gid_t gid)
     /*  */
 229 {
 230         if (suser())
 231                 current->gid = current->egid = current->sgid = current->fsgid = gid;
 232         else if ((gid == current->gid) || (gid == current->sgid))
 233                 current->egid = current->fsgid = gid;
 234         else
 235                 return -EPERM;
 236         return 0;
 237 }
 238 
 239 asmlinkage int sys_acct(void)
     /*  */
 240 {
 241         return -ENOSYS;
 242 }
 243 
 244 asmlinkage int sys_phys(void)
     /*  */
 245 {
 246         return -ENOSYS;
 247 }
 248 
 249 asmlinkage int sys_lock(void)
     /*  */
 250 {
 251         return -ENOSYS;
 252 }
 253 
 254 asmlinkage int sys_mpx(void)
     /*  */
 255 {
 256         return -ENOSYS;
 257 }
 258 
 259 asmlinkage int sys_ulimit(void)
     /*  */
 260 {
 261         return -ENOSYS;
 262 }
 263 
 264 asmlinkage int sys_old_syscall(void)
     /*  */
 265 {
 266         return -ENOSYS;
 267 }
 268 
 269 /*
 270  * Unprivileged users may change the real uid to the effective uid
 271  * or vice versa.  (BSD-style)
 272  *
 273  * If you set the real uid at all, or set the effective uid to a value not
 274  * equal to the real uid, then the saved uid is set to the new effective uid.
 275  *
 276  * This makes it possible for a setuid program to completely drop its
 277  * privileges, which is often a useful assertion to make when you are doing
 278  * a security audit over a program.
 279  *
 280  * The general idea is that a program which uses just setreuid() will be
 281  * 100% compatible with BSD.  A program which uses just setuid() will be
 282  * 100% compatible with POSIX w/ Saved ID's. 
 283  */
 284 asmlinkage int sys_setreuid(uid_t ruid, uid_t euid)
     /*  */
 285 {
 286         int old_ruid = current->uid;
 287 
 288         if (ruid != (uid_t) -1) {
 289                 if ((old_ruid == ruid) || 
 290                     (current->euid==ruid) ||
 291                     suser())
 292                         current->uid = ruid;
 293                 else
 294                         return(-EPERM);
 295         }
 296         if (euid != (uid_t) -1) {
 297                 if ((old_ruid == euid) ||
 298                     (current->euid == euid) ||
 299                     (current->suid == euid) ||
 300                     suser())
 301                         current->euid = euid;
 302                 else {
 303                         current->uid = old_ruid;
 304                         return(-EPERM);
 305                 }
 306         }
 307         if (ruid != (uid_t) -1 ||
 308             (euid != (uid_t) -1 && euid != old_ruid))
 309                 current->suid = current->euid;
 310         current->fsuid = current->euid;
 311         return 0;
 312 }
 313 
 314 /*
 315  * setuid() is implemented like SysV w/ SAVED_IDS 
 316  * 
 317  * Note that SAVED_ID's is deficient in that a setuid root program
 318  * like sendmail, for example, cannot set its uid to be a normal 
 319  * user and then switch back, because if you're root, setuid() sets
 320  * the saved uid too.  If you don't like this, blame the bright people
 321  * in the POSIX committee and/or USG.  Note that the BSD-style setreuid()
 322  * will allow a root program to temporarily drop privileges and be able to
 323  * regain them by swapping the real and effective uid.  
 324  */
 325 asmlinkage int sys_setuid(uid_t uid)
     /*  */
 326 {
 327         if (suser())
 328                 current->uid = current->euid = current->suid = current->fsuid = uid;
 329         else if ((uid == current->uid) || (uid == current->suid))
 330                 current->fsuid = current->euid = uid;
 331         else
 332                 return -EPERM;
 333         return(0);
 334 }
 335 
 336 /*
 337  * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This
 338  * is used for "access()" and for the NFS daemon (letting nfsd stay at
 339  * whatever uid it wants to). It normally shadows "euid", except when
 340  * explicitly set by setfsuid() or for access..
 341  */
 342 asmlinkage int sys_setfsuid(uid_t uid)
     /*  */
 343 {
 344         int old_fsuid = current->fsuid;
 345 
 346         if (uid == current->uid || uid == current->euid ||
 347             uid == current->suid || uid == current->fsuid || suser())
 348                 current->fsuid = uid;
 349         return old_fsuid;
 350 }
 351 
 352 /*
 353  * Samma på svenska..
 354  */
 355 asmlinkage int sys_setfsgid(gid_t gid)
     /*  */
 356 {
 357         int old_fsgid = current->fsgid;
 358 
 359         if (gid == current->gid || gid == current->egid ||
 360             gid == current->sgid || gid == current->fsgid || suser())
 361                 current->fsgid = gid;
 362         return old_fsgid;
 363 }
 364 
 365 asmlinkage int sys_times(struct tms * tbuf)
     /*  */
 366 {
 367         if (tbuf) {
 368                 int error = verify_area(VERIFY_WRITE,tbuf,sizeof *tbuf);
 369                 if (error)
 370                         return error;
 371                 put_fs_long(current->utime,(unsigned long *)&tbuf->tms_utime);
 372                 put_fs_long(current->stime,(unsigned long *)&tbuf->tms_stime);
 373                 put_fs_long(current->cutime,(unsigned long *)&tbuf->tms_cutime);
 374                 put_fs_long(current->cstime,(unsigned long *)&tbuf->tms_cstime);
 375         }
 376         return jiffies;
 377 }
 378 
 379 asmlinkage int sys_brk(unsigned long brk)
     /*  */
 380 {
 381         int freepages;
 382         unsigned long rlim;
 383         unsigned long newbrk, oldbrk;
 384 
 385         if (brk < current->mm->end_code)
 386                 return current->mm->brk;
 387         newbrk = PAGE_ALIGN(brk);
 388         oldbrk = PAGE_ALIGN(current->mm->brk);
 389         if (oldbrk == newbrk)
 390                 return current->mm->brk = brk;
 391 
 392         /*
 393          * Always allow shrinking brk
 394          */
 395         if (brk <= current->mm->brk) {
 396                 current->mm->brk = brk;
 397                 do_munmap(newbrk, oldbrk-newbrk);
 398                 return brk;
 399         }
 400         /*
 401          * Check against rlimit and stack..
 402          */
 403         rlim = current->rlim[RLIMIT_DATA].rlim_cur;
 404         if (rlim >= RLIM_INFINITY)
 405                 rlim = ~0;
 406         if (brk - current->mm->end_code > rlim ||
 407             brk >= current->mm->start_stack - 16384)
 408                 return current->mm->brk;
 409         /*
 410          * Check against existing mmap mappings.
 411          */
 412         if (find_vma_intersection(current, oldbrk, newbrk))
 413                 return current->mm->brk;
 414         /*
 415          * stupid algorithm to decide if we have enough memory: while
 416          * simple, it hopefully works in most obvious cases.. Easy to
 417          * fool it, but this should catch most mistakes.
 418          */
 419         freepages = buffermem >> 12;
 420         freepages += nr_free_pages;
 421         freepages += nr_swap_pages;
 422         freepages -= (high_memory - 0x100000) >> 16;
 423         freepages -= (newbrk-oldbrk) >> 12;
 424         if (freepages < 0)
 425                 return current->mm->brk;
 426 #if 0
 427         freepages += current->mm->rss;
 428         freepages -= oldbrk >> 12;
 429         if (freepages < 0)
 430                 return current->mm->brk;
 431 #endif
 432         /*
 433          * Ok, we have probably got enough memory - let it rip.
 434          */
 435         current->mm->brk = brk;
 436         do_mmap(NULL, oldbrk, newbrk-oldbrk,
 437                 PROT_READ|PROT_WRITE|PROT_EXEC,
 438                 MAP_FIXED|MAP_PRIVATE, 0);
 439         return brk;
 440 }
 441 
 442 /*
 443  * This needs some heave checking ...
 444  * I just haven't get the stomach for it. I also don't fully
 445  * understand sessions/pgrp etc. Let somebody who does explain it.
 446  *
 447  * OK, I think I have the protection semantics right.... this is really
 448  * only important on a multi-user system anyway, to make sure one user
 449  * can't send a signal to a process owned by another.  -TYT, 12/12/91
 450  *
 451  * Auch. Had to add the 'did_exec' flag to conform completely to POSIX.
 452  * LBT 04.03.94
 453  */
 454 asmlinkage int sys_setpgid(pid_t pid, pid_t pgid)
     /*  */
 455 {
 456         struct task_struct * p;
 457 
 458         if (!pid)
 459                 pid = current->pid;
 460         if (!pgid)
 461                 pgid = pid;
 462         if (pgid < 0)
 463                 return -EINVAL;
 464         for_each_task(p) {
 465                 if (p->pid == pid)
 466                         goto found_task;
 467         }
 468         return -ESRCH;
 469 
 470 found_task:
 471         if (p->p_pptr == current || p->p_opptr == current) {
 472                 if (p->session != current->session)
 473                         return -EPERM;
 474                 if (p->did_exec)
 475                         return -EACCES;
 476         } else if (p != current)
 477                 return -ESRCH;
 478         if (p->leader)
 479                 return -EPERM;
 480         if (pgid != pid) {
 481                 struct task_struct * tmp;
 482                 for_each_task (tmp) {
 483                         if (tmp->pgrp == pgid &&
 484                          tmp->session == current->session)
 485                                 goto ok_pgid;
 486                 }
 487                 return -EPERM;
 488         }
 489 
 490 ok_pgid:
 491         p->pgrp = pgid;
 492         return 0;
 493 }
 494 
 495 asmlinkage int sys_getpgid(pid_t pid)
     /*  */
 496 {
 497         struct task_struct * p;
 498 
 499         if (!pid)
 500                 return current->pgrp;
 501         for_each_task(p) {
 502                 if (p->pid == pid)
 503                         return p->pgrp;
 504         }
 505         return -ESRCH;
 506 }
 507 
 508 asmlinkage int sys_getpgrp(void)
     /*  */
 509 {
 510         return current->pgrp;
 511 }
 512 
 513 asmlinkage int sys_setsid(void)
     /*  */
 514 {
 515         if (current->leader)
 516                 return -EPERM;
 517         current->leader = 1;
 518         current->session = current->pgrp = current->pid;
 519         current->tty = NULL;
 520         return current->pgrp;
 521 }
 522 
 523 /*
 524  * Supplementary group ID's
 525  */
 526 asmlinkage int sys_getgroups(int gidsetsize, gid_t *grouplist)
     /*  */
 527 {
 528         int i;
 529 
 530         if (gidsetsize) {
 531                 i = verify_area(VERIFY_WRITE, grouplist, sizeof(gid_t) * gidsetsize);
 532                 if (i)
 533                         return i;
 534         }
 535         for (i = 0 ; (i < NGROUPS) && (current->groups[i] != NOGROUP) ; i++) {
 536                 if (!gidsetsize)
 537                         continue;
 538                 if (i >= gidsetsize)
 539                         break;
 540                 put_fs_word(current->groups[i], (short *) grouplist);
 541                 grouplist++;
 542         }
 543         return(i);
 544 }
 545 
 546 asmlinkage int sys_setgroups(int gidsetsize, gid_t *grouplist)
     /*  */
 547 {
 548         int     i;
 549 
 550         if (!suser())
 551                 return -EPERM;
 552         if (gidsetsize > NGROUPS)
 553                 return -EINVAL;
 554         for (i = 0; i < gidsetsize; i++, grouplist++) {
 555                 current->groups[i] = get_fs_word((unsigned short *) grouplist);
 556         }
 557         if (i < NGROUPS)
 558                 current->groups[i] = NOGROUP;
 559         return 0;
 560 }
 561 
 562 int in_group_p(gid_t grp)
     /*  */
 563 {
 564         int     i;
 565 
 566         if (grp == current->fsgid)
 567                 return 1;
 568 
 569         for (i = 0; i < NGROUPS; i++) {
 570                 if (current->groups[i] == NOGROUP)
 571                         break;
 572                 if (current->groups[i] == grp)
 573                         return 1;
 574         }
 575         return 0;
 576 }
 577 
 578 asmlinkage int sys_newuname(struct new_utsname * name)
     /*  */
 579 {
 580         int error;
 581 
 582         if (!name)
 583                 return -EFAULT;
 584         error = verify_area(VERIFY_WRITE, name, sizeof *name);
 585         if (!error)
 586                 memcpy_tofs(name,&system_utsname,sizeof *name);
 587         return error;
 588 }
 589 
 590 asmlinkage int sys_uname(struct old_utsname * name)
     /*  */
 591 {
 592         int error;
 593         if (!name)
 594                 return -EFAULT;
 595         error = verify_area(VERIFY_WRITE, name,sizeof *name);
 596         if (error)
 597                 return error;
 598         memcpy_tofs(&name->sysname,&system_utsname.sysname,
 599                 sizeof (system_utsname.sysname));
 600         memcpy_tofs(&name->nodename,&system_utsname.nodename,
 601                 sizeof (system_utsname.nodename));
 602         memcpy_tofs(&name->release,&system_utsname.release,
 603                 sizeof (system_utsname.release));
 604         memcpy_tofs(&name->version,&system_utsname.version,
 605                 sizeof (system_utsname.version));
 606         memcpy_tofs(&name->machine,&system_utsname.machine,
 607                 sizeof (system_utsname.machine));
 608         return 0;
 609 }
 610 
 611 asmlinkage int sys_olduname(struct oldold_utsname * name)
     /*  */
 612 {
 613         int error;
 614         if (!name)
 615                 return -EFAULT;
 616         error = verify_area(VERIFY_WRITE, name,sizeof *name);
 617         if (error)
 618                 return error;
 619         memcpy_tofs(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);
 620         put_fs_byte(0,name->sysname+__OLD_UTS_LEN);
 621         memcpy_tofs(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);
 622         put_fs_byte(0,name->nodename+__OLD_UTS_LEN);
 623         memcpy_tofs(&name->release,&system_utsname.release,__OLD_UTS_LEN);
 624         put_fs_byte(0,name->release+__OLD_UTS_LEN);
 625         memcpy_tofs(&name->version,&system_utsname.version,__OLD_UTS_LEN);
 626         put_fs_byte(0,name->version+__OLD_UTS_LEN);
 627         memcpy_tofs(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);
 628         put_fs_byte(0,name->machine+__OLD_UTS_LEN);
 629         return 0;
 630 }
 631 
 632 /*
 633  * Only sethostname; gethostname can be implemented by calling uname()
 634  */
 635 asmlinkage int sys_sethostname(char *name, int len)
     /*  */
 636 {
 637         int     i;
 638         
 639         if (!suser())
 640                 return -EPERM;
 641         if (len > __NEW_UTS_LEN)
 642                 return -EINVAL;
 643         for (i=0; i < len; i++) {
 644                 if ((system_utsname.nodename[i] = get_fs_byte(name+i)) == 0)
 645                         return 0;
 646         }
 647         system_utsname.nodename[i] = 0;
 648         return 0;
 649 }
 650 
 651 /*
 652  * Only setdomainname; getdomainname can be implemented by calling
 653  * uname()
 654  */
 655 asmlinkage int sys_setdomainname(char *name, int len)
     /*  */
 656 {
 657         int     i;
 658         
 659         if (!suser())
 660                 return -EPERM;
 661         if (len > __NEW_UTS_LEN)
 662                 return -EINVAL;
 663         for (i=0; i < len; i++) {
 664                 if ((system_utsname.domainname[i] = get_fs_byte(name+i)) == 0)
 665                         return 0;
 666         }
 667         system_utsname.domainname[i] = 0;
 668         return 0;
 669 }
 670 
 671 asmlinkage int sys_getrlimit(unsigned int resource, struct rlimit *rlim)
     /*  */
 672 {
 673         int error;
 674 
 675         if (resource >= RLIM_NLIMITS)
 676                 return -EINVAL;
 677         error = verify_area(VERIFY_WRITE,rlim,sizeof *rlim);
 678         if (error)
 679                 return error;
 680         put_fs_long(current->rlim[resource].rlim_cur, 
 681                     (unsigned long *) rlim);
 682         put_fs_long(current->rlim[resource].rlim_max, 
 683                     ((unsigned long *) rlim)+1);
 684         return 0;       
 685 }
 686 
 687 asmlinkage int sys_setrlimit(unsigned int resource, struct rlimit *rlim)
     /*  */
 688 {
 689         struct rlimit new_rlim, *old_rlim;
 690         int err;
 691 
 692         if (resource >= RLIM_NLIMITS)
 693                 return -EINVAL;
 694         err = verify_area(VERIFY_READ, rlim, sizeof(*rlim));
 695         if (err)
 696                 return err;
 697         memcpy_fromfs(&new_rlim, rlim, sizeof(*rlim));
 698         old_rlim = current->rlim + resource;
 699         if (((new_rlim.rlim_cur > old_rlim->rlim_max) ||
 700              (new_rlim.rlim_max > old_rlim->rlim_max)) &&
 701             !suser())
 702                 return -EPERM;
 703         if (resource == RLIMIT_NOFILE) {
 704                 if (new_rlim.rlim_cur > NR_OPEN || new_rlim.rlim_max > NR_OPEN)
 705                         return -EPERM;
 706         }
 707         *old_rlim = new_rlim;
 708         return 0;
 709 }
 710 
 711 /*
 712  * It would make sense to put struct rusage in the task_struct,
 713  * except that would make the task_struct be *really big*.  After
 714  * task_struct gets moved into malloc'ed memory, it would
 715  * make sense to do this.  It will make moving the rest of the information
 716  * a lot simpler!  (Which we're not doing right now because we're not
 717  * measuring them yet).
 718  */
 719 int getrusage(struct task_struct *p, int who, struct rusage *ru)
     /*  */
 720 {
 721         int error;
 722         struct rusage r;
 723 
 724         error = verify_area(VERIFY_WRITE, ru, sizeof *ru);
 725         if (error)
 726                 return error;
 727         memset((char *) &r, 0, sizeof(r));
 728         switch (who) {
 729                 case RUSAGE_SELF:
 730                         r.ru_utime.tv_sec = CT_TO_SECS(p->utime);
 731                         r.ru_utime.tv_usec = CT_TO_USECS(p->utime);
 732                         r.ru_stime.tv_sec = CT_TO_SECS(p->stime);
 733                         r.ru_stime.tv_usec = CT_TO_USECS(p->stime);
 734                         r.ru_minflt = p->mm->min_flt;
 735                         r.ru_majflt = p->mm->maj_flt;
 736                         break;
 737                 case RUSAGE_CHILDREN:
 738                         r.ru_utime.tv_sec = CT_TO_SECS(p->cutime);
 739                         r.ru_utime.tv_usec = CT_TO_USECS(p->cutime);
 740                         r.ru_stime.tv_sec = CT_TO_SECS(p->cstime);
 741                         r.ru_stime.tv_usec = CT_TO_USECS(p->cstime);
 742                         r.ru_minflt = p->mm->cmin_flt;
 743                         r.ru_majflt = p->mm->cmaj_flt;
 744                         break;
 745                 default:
 746                         r.ru_utime.tv_sec = CT_TO_SECS(p->utime + p->cutime);
 747                         r.ru_utime.tv_usec = CT_TO_USECS(p->utime + p->cutime);
 748                         r.ru_stime.tv_sec = CT_TO_SECS(p->stime + p->cstime);
 749                         r.ru_stime.tv_usec = CT_TO_USECS(p->stime + p->cstime);
 750                         r.ru_minflt = p->mm->min_flt + p->mm->cmin_flt;
 751                         r.ru_majflt = p->mm->maj_flt + p->mm->cmaj_flt;
 752                         break;
 753         }
 754         memcpy_tofs(ru, &r, sizeof(r));
 755         return 0;
 756 }
 757 
 758 asmlinkage int sys_getrusage(int who, struct rusage *ru)
     /*  */
 759 {
 760         if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN)
 761                 return -EINVAL;
 762         return getrusage(current, who, ru);
 763 }
 764 
 765 asmlinkage int sys_umask(int mask)
     /*  */
 766 {
 767         int old = current->fs->umask;
 768 
 769         current->fs->umask = mask & S_IRWXUGO;
 770         return (old);
 771 }

/* */