root/kernel/sys.c

/* */

DEFINITIONS

1. proc_sel
2. sys_setpriority
3. sys_getpriority
4. sys_profil
5. sys_ftime
6. sys_break
7. sys_stty
8. sys_gtty
9. sys_prof
10. save_v86_state
11. mark_screen_rdonly
12. sys_vm86
13. sys_reboot
14. ctrl_alt_del
15. sys_setregid
16. sys_setgid
17. sys_acct
18. sys_phys
19. sys_lock
20. sys_mpx
21. sys_ulimit
22. sys_old_syscall
23. sys_setreuid
24. sys_setuid
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/config.h>
   8 #include <linux/errno.h>
   9 #include <linux/sched.h>
  10 #include <linux/kernel.h>
  11 #include <linux/times.h>
  12 #include <linux/utsname.h>
  13 #include <linux/param.h>
  14 #include <linux/resource.h>
  15 #include <linux/signal.h>
  16 #include <linux/string.h>
  17 #include <linux/ptrace.h>
  18 #include <linux/stat.h>
  19 #include <linux/mman.h>
  20 
  21 #include <asm/segment.h>
  22 #include <asm/io.h>
  23 
  24 /*
  25  * this indicates wether 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 static int proc_sel(struct task_struct *p, int which, int who)
     /*  */
  34 {
  35         switch (which) {
  36                 case PRIO_PROCESS:
  37                         if (!who && p == current)
  38                                 return 1;
  39                         return(p->pid == who);
  40                 case PRIO_PGRP:
  41                         if (!who)
  42                                 who = current->pgrp;
  43                         return(p->pgrp == who);
  44                 case PRIO_USER:
  45                         if (!who)
  46                                 who = current->uid;
  47                         return(p->uid == who);
  48         }
  49         return 0;
  50 }
  51 
  52 asmlinkage int sys_setpriority(int which, int who, int niceval)
     /*  */
  53 {
  54         struct task_struct **p;
  55         int error = ESRCH;
  56         int priority;
  57 
  58         if (which > 2 || which < 0)
  59                 return -EINVAL;
  60 
  61         if ((priority = PZERO - niceval) <= 0)
  62                 priority = 1;
  63 
  64         for(p = &LAST_TASK; p > &FIRST_TASK; --p) {
  65                 if (!*p || !proc_sel(*p, which, who))
  66                         continue;
  67                 if ((*p)->uid != current->euid &&
  68                         (*p)->uid != current->uid && !suser()) {
  69                         error = EPERM;
  70                         continue;
  71                 }
  72                 if (error == ESRCH)
  73                         error = 0;
  74                 if (priority > (*p)->priority && !suser())
  75                         error = EACCES;
  76                 else
  77                         (*p)->priority = priority;
  78         }
  79         return -error;
  80 }
  81 
  82 asmlinkage int sys_getpriority(int which, int who)
     /*  */
  83 {
  84         struct task_struct **p;
  85         int max_prio = 0;
  86 
  87         if (which > 2 || which < 0)
  88                 return -EINVAL;
  89 
  90         for(p = &LAST_TASK; p > &FIRST_TASK; --p) {
  91                 if (!*p || !proc_sel(*p, which, who))
  92                         continue;
  93                 if ((*p)->priority > max_prio)
  94                         max_prio = (*p)->priority;
  95         }
  96         return(max_prio ? max_prio : -ESRCH);
  97 }
  98 
  99 asmlinkage int sys_profil(void)
     /*  */
 100 {
 101         return -ENOSYS;
 102 }
 103 
 104 asmlinkage int sys_ftime(void)
     /*  */
 105 {
 106         return -ENOSYS;
 107 }
 108 
 109 asmlinkage int sys_break(void)
     /*  */
 110 {
 111         return -ENOSYS;
 112 }
 113 
 114 asmlinkage int sys_stty(void)
     /*  */
 115 {
 116         return -ENOSYS;
 117 }
 118 
 119 asmlinkage int sys_gtty(void)
     /*  */
 120 {
 121         return -ENOSYS;
 122 }
 123 
 124 asmlinkage int sys_prof(void)
     /*  */
 125 {
 126         return -ENOSYS;
 127 }
 128 
 129 asmlinkage unsigned long save_v86_state(struct vm86_regs * regs)
     /*  */
 130 {
 131         unsigned long stack;
 132 
 133         if (!current->vm86_info) {
 134                 printk("no vm86_info: BAD\n");
 135                 do_exit(SIGSEGV);
 136         }
 137         memcpy_tofs(&(current->vm86_info->regs),regs,sizeof(*regs));
 138         put_fs_long(current->screen_bitmap,&(current->vm86_info->screen_bitmap));
 139         stack = current->tss.esp0;
 140         current->tss.esp0 = current->saved_kernel_stack;
 141         current->saved_kernel_stack = 0;
 142         return stack;
 143 }
 144 
 145 static void mark_screen_rdonly(struct task_struct * tsk)
     /*  */
 146 {
 147         unsigned long tmp;
 148         unsigned long *pg_table;
 149 
 150         if ((tmp = tsk->tss.cr3) != 0) {
 151                 tmp = *(unsigned long *) tmp;
 152                 if (tmp & PAGE_PRESENT) {
 153                         tmp &= PAGE_MASK;
 154                         pg_table = (0xA0000 >> PAGE_SHIFT) + (unsigned long *) tmp;
 155                         tmp = 32;
 156                         while (tmp--) {
 157                                 if (PAGE_PRESENT & *pg_table)
 158                                         *pg_table &= ~PAGE_RW;
 159                                 pg_table++;
 160                         }
 161                 }
 162         }
 163 }
 164 
 165 asmlinkage int sys_vm86(struct vm86_struct * v86)
     /*  */
 166 {
 167         struct vm86_struct info;
 168         struct pt_regs * pt_regs = (struct pt_regs *) &v86;
 169 
 170         if (current->saved_kernel_stack)
 171                 return -EPERM;
 172         memcpy_fromfs(&info,v86,sizeof(info));
 173 /*
 174  * make sure the vm86() system call doesn't try to do anything silly
 175  */
 176         info.regs.__null_ds = 0;
 177         info.regs.__null_es = 0;
 178         info.regs.__null_fs = 0;
 179         info.regs.__null_gs = 0;
 180 /*
 181  * The eflags register is also special: we cannot trust that the user
 182  * has set it up safely, so this makes sure interrupt etc flags are
 183  * inherited from protected mode.
 184  */
 185         info.regs.eflags &= 0x00000dd5;
 186         info.regs.eflags |= ~0x00000dd5 & pt_regs->eflags;
 187         info.regs.eflags |= VM_MASK;
 188         current->saved_kernel_stack = current->tss.esp0;
 189         current->tss.esp0 = (unsigned long) pt_regs;
 190         current->vm86_info = v86;
 191         current->screen_bitmap = info.screen_bitmap;
 192         if (info.flags & VM86_SCREEN_BITMAP)
 193                 mark_screen_rdonly(current);
 194         __asm__ __volatile__("movl %0,%%esp\n\t"
 195                 "pushl $ret_from_sys_call\n\t"
 196                 "ret"
 197                 : /* no outputs */
 198                 :"g" ((long) &(info.regs)),"a" (info.regs.eax));
 199         return 0;
 200 }
 201 
 202 extern void hard_reset_now(void);
 203 
 204 /*
 205  * Reboot system call: for obvious reasons only root may call it,
 206  * and even root needs to set up some magic numbers in the registers
 207  * so that some mistake won't make this reboot the whole machine.
 208  * You can also set the meaning of the ctrl-alt-del-key here.
 209  *
 210  * reboot doesn't sync: do that yourself before calling this.
 211  */
 212 asmlinkage int sys_reboot(int magic, int magic_too, int flag)
     /*  */
 213 {
 214         if (!suser())
 215                 return -EPERM;
 216         if (magic != 0xfee1dead || magic_too != 672274793)
 217                 return -EINVAL;
 218         if (flag == 0x01234567)
 219                 hard_reset_now();
 220         else if (flag == 0x89ABCDEF)
 221                 C_A_D = 1;
 222         else if (!flag)
 223                 C_A_D = 0;
 224         else
 225                 return -EINVAL;
 226         return (0);
 227 }
 228 
 229 /*
 230  * This function gets called by ctrl-alt-del - ie the keyboard interrupt.
 231  * As it's called within an interrupt, it may NOT sync: the only choice
 232  * is wether to reboot at once, or just ignore the ctrl-alt-del.
 233  */
 234 void ctrl_alt_del(void)
     /*  */
 235 {
 236         if (C_A_D)
 237                 hard_reset_now();
 238         else
 239                 send_sig(SIGINT,task[1],1);
 240 }
 241         
 242 
 243 /*
 244  * This is done BSD-style, with no consideration of the saved gid, except
 245  * that if you set the effective gid, it sets the saved gid too.  This 
 246  * makes it possible for a setgid program to completely drop its privileges,
 247  * which is often a useful assertion to make when you are doing a security
 248  * audit over a program.
 249  *
 250  * The general idea is that a program which uses just setregid() will be
 251  * 100% compatible with BSD.  A program which uses just setgid() will be
 252  * 100% compatible with POSIX w/ Saved ID's. 
 253  */
 254 asmlinkage int sys_setregid(gid_t rgid, gid_t egid)
     /*  */
 255 {
 256         int old_rgid = current->gid;
 257 
 258         if (rgid != (gid_t) -1) {
 259                 if ((current->egid==rgid) ||
 260                     (old_rgid == rgid) || 
 261                     suser())
 262                         current->gid = rgid;
 263                 else
 264                         return(-EPERM);
 265         }
 266         if (egid != (gid_t) -1) {
 267                 if ((old_rgid == egid) ||
 268                     (current->egid == egid) ||
 269                     suser()) {
 270                         current->egid = egid;
 271                         current->sgid = egid;
 272                 } else {
 273                         current->gid = old_rgid;
 274                         return(-EPERM);
 275                 }
 276         }
 277         return 0;
 278 }
 279 
 280 /*
 281  * setgid() is implemeneted like SysV w/ SAVED_IDS 
 282  */
 283 asmlinkage int sys_setgid(gid_t gid)
     /*  */
 284 {
 285         if (suser())
 286                 current->gid = current->egid = current->sgid = gid;
 287         else if ((gid == current->gid) || (gid == current->sgid))
 288                 current->egid = gid;
 289         else
 290                 return -EPERM;
 291         return 0;
 292 }
 293 
 294 asmlinkage int sys_acct(void)
     /*  */
 295 {
 296         return -ENOSYS;
 297 }
 298 
 299 asmlinkage int sys_phys(void)
     /*  */
 300 {
 301         return -ENOSYS;
 302 }
 303 
 304 asmlinkage int sys_lock(void)
     /*  */
 305 {
 306         return -ENOSYS;
 307 }
 308 
 309 asmlinkage int sys_mpx(void)
     /*  */
 310 {
 311         return -ENOSYS;
 312 }
 313 
 314 asmlinkage int sys_ulimit(void)
     /*  */
 315 {
 316         return -ENOSYS;
 317 }
 318 
 319 asmlinkage int sys_old_syscall(void)
     /*  */
 320 {
 321         return -ENOSYS;
 322 }
 323 
 324 /*
 325  * Unprivileged users may change the real user id to the effective uid
 326  * or vice versa.  (BSD-style)
 327  *
 328  * When you set the effective uid, it sets the saved uid too.  This 
 329  * makes it possible for a setuid program to completely drop its privileges,
 330  * which is often a useful assertion to make when you are doing a security
 331  * audit over a program.
 332  *
 333  * The general idea is that a program which uses just setreuid() will be
 334  * 100% compatible with BSD.  A program which uses just setuid() will be
 335  * 100% compatible with POSIX w/ Saved ID's. 
 336  */
 337 asmlinkage int sys_setreuid(uid_t ruid, uid_t euid)
     /*  */
 338 {
 339         int old_ruid = current->uid;
 340         
 341         if (ruid != (uid_t) -1) {
 342                 if ((current->euid==ruid) ||
 343                     (old_ruid == ruid) ||
 344                     suser())
 345                         current->uid = ruid;
 346                 else
 347                         return(-EPERM);
 348         }
 349         if (euid != (uid_t) -1) {
 350                 if ((old_ruid == euid) ||
 351                     (current->euid == euid) ||
 352                     suser()) {
 353                         current->euid = euid;
 354                         current->suid = euid;
 355                 } else {
 356                         current->uid = old_ruid;
 357                         return(-EPERM);
 358                 }
 359         }
 360         return 0;
 361 }
 362 
 363 /*
 364  * setuid() is implemeneted like SysV w/ SAVED_IDS 
 365  * 
 366  * Note that SAVED_ID's is deficient in that a setuid root program
 367  * like sendmail, for example, cannot set its uid to be a normal 
 368  * user and then switch back, because if you're root, setuid() sets
 369  * the saved uid too.  If you don't like this, blame the bright people
 370  * in the POSIX commmittee and/or USG.  Note that the BSD-style setreuid()
 371  * will allow a root program to temporarily drop privileges and be able to
 372  * regain them by swapping the real and effective uid.  
 373  */
 374 asmlinkage int sys_setuid(uid_t uid)
     /*  */
 375 {
 376         if (suser())
 377                 current->uid = current->euid = current->suid = uid;
 378         else if ((uid == current->uid) || (uid == current->suid))
 379                 current->euid = uid;
 380         else
 381                 return -EPERM;
 382         return(0);
 383 }
 384 
 385 asmlinkage int sys_times(struct tms * tbuf)
     /*  */
 386 {
 387         if (tbuf) {
 388                 int error = verify_area(VERIFY_WRITE,tbuf,sizeof *tbuf);
 389                 if (error)
 390                         return error;
 391                 put_fs_long(current->utime,(unsigned long *)&tbuf->tms_utime);
 392                 put_fs_long(current->stime,(unsigned long *)&tbuf->tms_stime);
 393                 put_fs_long(current->cutime,(unsigned long *)&tbuf->tms_cutime);
 394                 put_fs_long(current->cstime,(unsigned long *)&tbuf->tms_cstime);
 395         }
 396         return jiffies;
 397 }
 398 
 399 asmlinkage int sys_brk(unsigned long brk)
     /*  */
 400 {
 401         int freepages;
 402         unsigned long rlim;
 403         unsigned long newbrk, oldbrk;
 404 
 405         if (brk < current->end_code)
 406                 return current->brk;
 407         newbrk = PAGE_ALIGN(brk);
 408         oldbrk = PAGE_ALIGN(current->brk);
 409         if (oldbrk == newbrk)
 410                 return current->brk = brk;
 411 
 412         /*
 413          * Always allow shrinking brk
 414          */
 415         if (brk <= current->brk) {
 416                 current->brk = brk;
 417                 do_munmap(newbrk, oldbrk-newbrk);
 418                 return brk;
 419         }
 420         /*
 421          * Check against rlimit and stack..
 422          */
 423         rlim = current->rlim[RLIMIT_DATA].rlim_cur;
 424         if (rlim >= RLIM_INFINITY)
 425                 rlim = ~0;
 426         if (brk - current->end_code > rlim || brk >= current->start_stack - 16384)
 427                 return current->brk;
 428         /*
 429          * stupid algorithm to decide if we have enough memory: while
 430          * simple, it hopefully works in most obvious cases.. Easy to
 431          * fool it, but this should catch most mistakes.
 432          */
 433         freepages = buffermem >> 12;
 434         freepages += nr_free_pages;
 435         freepages += nr_swap_pages;
 436         freepages -= (high_memory - 0x100000) >> 16;
 437         freepages -= (newbrk-oldbrk) >> 12;
 438         if (freepages < 0)
 439                 return current->brk;
 440 #if 0
 441         freepages += current->rss;
 442         freepages -= oldbrk >> 12;
 443         if (freepages < 0)
 444                 return current->brk;
 445 #endif
 446         /*
 447          * Ok, we have probably got enough memory - let it rip.
 448          */
 449         current->brk = brk;
 450         do_mmap(NULL, oldbrk, newbrk-oldbrk,
 451                 PROT_READ|PROT_WRITE|PROT_EXEC,
 452                 MAP_FIXED|MAP_PRIVATE, 0);
 453         return brk;
 454 }
 455 
 456 /*
 457  * This needs some heave checking ...
 458  * I just haven't get the stomach for it. I also don't fully
 459  * understand sessions/pgrp etc. Let somebody who does explain it.
 460  *
 461  * OK, I think I have the protection semantics right.... this is really
 462  * only important on a multi-user system anyway, to make sure one user
 463  * can't send a signal to a process owned by another.  -TYT, 12/12/91
 464  */
 465 asmlinkage int sys_setpgid(pid_t pid, pid_t pgid)
     /*  */
 466 {
 467         int i; 
 468 
 469         if (!pid)
 470                 pid = current->pid;
 471         if (!pgid)
 472                 pgid = current->pid;
 473         if (pgid < 0)
 474                 return -EINVAL;
 475         for (i=0 ; i<NR_TASKS ; i++)
 476                 if (task[i] && (task[i]->pid == pid) &&
 477                     ((task[i]->p_pptr == current) || 
 478                      (task[i]->p_opptr == current) || 
 479                      (task[i] == current))) {
 480                         if (task[i]->leader)
 481                                 return -EPERM;
 482                         if ((task[i]->session != current->session) ||
 483                             ((pgid != pid) && 
 484                              (session_of_pgrp(pgid) != current->session)))
 485                                 return -EPERM;
 486                         task[i]->pgrp = pgid;
 487                         return 0;
 488                 }
 489         return -ESRCH;
 490 }
 491 
 492 asmlinkage int sys_getpgid(pid_t pid)
     /*  */
 493 {
 494         struct task_struct * p;
 495 
 496         if (!pid)
 497                 return current->pgrp;
 498         for_each_task(p) {
 499                 if (p->pid == pid)
 500                         return p->pgrp;
 501         }
 502         return -ESRCH;
 503 }
 504 
 505 asmlinkage int sys_getpgrp(void)
     /*  */
 506 {
 507         return current->pgrp;
 508 }
 509 
 510 asmlinkage int sys_setsid(void)
     /*  */
 511 {
 512         if (current->leader)
 513                 return -EPERM;
 514         current->leader = 1;
 515         current->session = current->pgrp = current->pid;
 516         current->tty = -1;
 517         return current->pgrp;
 518 }
 519 
 520 /*
 521  * Supplementary group ID's
 522  */
 523 asmlinkage int sys_getgroups(int gidsetsize, gid_t *grouplist)
     /*  */
 524 {
 525         int i;
 526 
 527         if (gidsetsize) {
 528                 i = verify_area(VERIFY_WRITE, grouplist, sizeof(gid_t) * gidsetsize);
 529                 if (i)
 530                         return i;
 531         }
 532         for (i = 0 ; (i < NGROUPS) && (current->groups[i] != NOGROUP) ; i++) {
 533                 if (!gidsetsize)
 534                         continue;
 535                 if (i >= gidsetsize)
 536                         break;
 537                 put_fs_word(current->groups[i], (short *) grouplist);
 538                 grouplist++;
 539         }
 540         return(i);
 541 }
 542 
 543 asmlinkage int sys_setgroups(int gidsetsize, gid_t *grouplist)
     /*  */
 544 {
 545         int     i;
 546 
 547         if (!suser())
 548                 return -EPERM;
 549         if (gidsetsize > NGROUPS)
 550                 return -EINVAL;
 551         for (i = 0; i < gidsetsize; i++, grouplist++) {
 552                 current->groups[i] = get_fs_word((unsigned short *) grouplist);
 553         }
 554         if (i < NGROUPS)
 555                 current->groups[i] = NOGROUP;
 556         return 0;
 557 }
 558 
 559 int in_group_p(gid_t grp)
     /*  */
 560 {
 561         int     i;
 562 
 563         if (grp == current->egid)
 564                 return 1;
 565 
 566         for (i = 0; i < NGROUPS; i++) {
 567                 if (current->groups[i] == NOGROUP)
 568                         break;
 569                 if (current->groups[i] == grp)
 570                         return 1;
 571         }
 572         return 0;
 573 }
 574 
 575 asmlinkage int sys_newuname(struct new_utsname * name)
     /*  */
 576 {
 577         int error;
 578 
 579         if (!name)
 580                 return -EFAULT;
 581         error = verify_area(VERIFY_WRITE, name, sizeof *name);
 582         if (!error)
 583                 memcpy_tofs(name,&system_utsname,sizeof *name);
 584         return error;
 585 }
 586 
 587 asmlinkage int sys_uname(struct old_utsname * name)
     /*  */
 588 {
 589         int error;
 590         if (!name)
 591                 return -EFAULT;
 592         error = verify_area(VERIFY_WRITE, name,sizeof *name);
 593         if (error)
 594                 return error;
 595         memcpy_tofs(&name->sysname,&system_utsname.sysname,
 596                 sizeof (system_utsname.sysname));
 597         memcpy_tofs(&name->nodename,&system_utsname.nodename,
 598                 sizeof (system_utsname.nodename));
 599         memcpy_tofs(&name->release,&system_utsname.release,
 600                 sizeof (system_utsname.release));
 601         memcpy_tofs(&name->version,&system_utsname.version,
 602                 sizeof (system_utsname.version));
 603         memcpy_tofs(&name->machine,&system_utsname.machine,
 604                 sizeof (system_utsname.machine));
 605         return 0;
 606 }
 607 
 608 asmlinkage int sys_olduname(struct oldold_utsname * name)
     /*  */
 609 {
 610         int error;
 611         if (!name)
 612                 return -EFAULT;
 613         error = verify_area(VERIFY_WRITE, name,sizeof *name);
 614         if (error)
 615                 return error;
 616         memcpy_tofs(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);
 617         put_fs_byte(0,name->sysname+__OLD_UTS_LEN);
 618         memcpy_tofs(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);
 619         put_fs_byte(0,name->nodename+__OLD_UTS_LEN);
 620         memcpy_tofs(&name->release,&system_utsname.release,__OLD_UTS_LEN);
 621         put_fs_byte(0,name->release+__OLD_UTS_LEN);
 622         memcpy_tofs(&name->version,&system_utsname.version,__OLD_UTS_LEN);
 623         put_fs_byte(0,name->version+__OLD_UTS_LEN);
 624         memcpy_tofs(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);
 625         put_fs_byte(0,name->machine+__OLD_UTS_LEN);
 626         return 0;
 627 }
 628 
 629 /*
 630  * Only sethostname; gethostname can be implemented by calling uname()
 631  */
 632 asmlinkage int sys_sethostname(char *name, int len)
     /*  */
 633 {
 634         int     i;
 635         
 636         if (!suser())
 637                 return -EPERM;
 638         if (len > __NEW_UTS_LEN)
 639                 return -EINVAL;
 640         for (i=0; i < len; i++) {
 641                 if ((system_utsname.nodename[i] = get_fs_byte(name+i)) == 0)
 642                         return 0;
 643         }
 644         system_utsname.nodename[i] = 0;
 645         return 0;
 646 }
 647 
 648 /*
 649  * Only setdomainname; getdomainname can be implemented by calling
 650  * uname()
 651  */
 652 asmlinkage int sys_setdomainname(char *name, int len)
     /*  */
 653 {
 654         int     i;
 655         
 656         if (!suser())
 657                 return -EPERM;
 658         if (len > __NEW_UTS_LEN)
 659                 return -EINVAL;
 660         for (i=0; i < len; i++) {
 661                 if ((system_utsname.domainname[i] = get_fs_byte(name+i)) == 0)
 662                         return 0;
 663         }
 664         system_utsname.domainname[i] = 0;
 665         return 0;
 666 }
 667 
 668 asmlinkage int sys_getrlimit(unsigned int resource, struct rlimit *rlim)
     /*  */
 669 {
 670         int error;
 671 
 672         if (resource >= RLIM_NLIMITS)
 673                 return -EINVAL;
 674         error = verify_area(VERIFY_WRITE,rlim,sizeof *rlim);
 675         if (error)
 676                 return error;
 677         put_fs_long(current->rlim[resource].rlim_cur, 
 678                     (unsigned long *) rlim);
 679         put_fs_long(current->rlim[resource].rlim_max, 
 680                     ((unsigned long *) rlim)+1);
 681         return 0;       
 682 }
 683 
 684 asmlinkage int sys_setrlimit(unsigned int resource, struct rlimit *rlim)
     /*  */
 685 {
 686         struct rlimit new_rlim, *old_rlim;
 687 
 688         if (resource >= RLIM_NLIMITS)
 689                 return -EINVAL;
 690         old_rlim = current->rlim + resource;
 691         new_rlim.rlim_cur = get_fs_long((unsigned long *) rlim);
 692         new_rlim.rlim_max = get_fs_long(((unsigned long *) rlim)+1);
 693         if (((new_rlim.rlim_cur > old_rlim->rlim_max) ||
 694              (new_rlim.rlim_max > old_rlim->rlim_max)) &&
 695             !suser())
 696                 return -EPERM;
 697         *old_rlim = new_rlim;
 698         return 0;
 699 }
 700 
 701 /*
 702  * It would make sense to put struct rusuage in the task_struct,
 703  * except that would make the task_struct be *really big*.  After
 704  * task_struct gets moved into malloc'ed memory, it would
 705  * make sense to do this.  It will make moving the rest of the information
 706  * a lot simpler!  (Which we're not doing right now because we're not
 707  * measuring them yet).
 708  */
 709 int getrusage(struct task_struct *p, int who, struct rusage *ru)
     /*  */
 710 {
 711         int error;
 712         struct rusage r;
 713         unsigned long   *lp, *lpend, *dest;
 714 
 715         error = verify_area(VERIFY_WRITE, ru, sizeof *ru);
 716         if (error)
 717                 return error;
 718         memset((char *) &r, 0, sizeof(r));
 719         switch (who) {
 720                 case RUSAGE_SELF:
 721                         r.ru_utime.tv_sec = CT_TO_SECS(p->utime);
 722                         r.ru_utime.tv_usec = CT_TO_USECS(p->utime);
 723                         r.ru_stime.tv_sec = CT_TO_SECS(p->stime);
 724                         r.ru_stime.tv_usec = CT_TO_USECS(p->stime);
 725                         r.ru_minflt = p->min_flt;
 726                         r.ru_majflt = p->maj_flt;
 727                         break;
 728                 case RUSAGE_CHILDREN:
 729                         r.ru_utime.tv_sec = CT_TO_SECS(p->cutime);
 730                         r.ru_utime.tv_usec = CT_TO_USECS(p->cutime);
 731                         r.ru_stime.tv_sec = CT_TO_SECS(p->cstime);
 732                         r.ru_stime.tv_usec = CT_TO_USECS(p->cstime);
 733                         r.ru_minflt = p->cmin_flt;
 734                         r.ru_majflt = p->cmaj_flt;
 735                         break;
 736                 default:
 737                         r.ru_utime.tv_sec = CT_TO_SECS(p->utime + p->cutime);
 738                         r.ru_utime.tv_usec = CT_TO_USECS(p->utime + p->cutime);
 739                         r.ru_stime.tv_sec = CT_TO_SECS(p->stime + p->cstime);
 740                         r.ru_stime.tv_usec = CT_TO_USECS(p->stime + p->cstime);
 741                         r.ru_minflt = p->min_flt + p->cmin_flt;
 742                         r.ru_majflt = p->maj_flt + p->cmaj_flt;
 743                         break;
 744         }
 745         lp = (unsigned long *) &r;
 746         lpend = (unsigned long *) (&r+1);
 747         dest = (unsigned long *) ru;
 748         for (; lp < lpend; lp++, dest++) 
 749                 put_fs_long(*lp, dest);
 750         return 0;
 751 }
 752 
 753 asmlinkage int sys_getrusage(int who, struct rusage *ru)
     /*  */
 754 {
 755         if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN)
 756                 return -EINVAL;
 757         return getrusage(current, who, ru);
 758 }
 759 
 760 asmlinkage int sys_umask(int mask)
     /*  */
 761 {
 762         int old = current->umask;
 763 
 764         current->umask = mask & S_IRWXUGO;
 765         return (old);
 766 }

/* */