lib/libkvm/kvm_proc.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1989, 1992, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software developed by the Computer Systems
   8  * Engineering group at Lawrence Berkeley Laboratory under DARPA contract
   9  * BG 91-66 and contributed to Berkeley.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36
  37 /*
  38  * Proc traversal interface for kvm.  ps and w are (probably) the exclusive
  39  * users of this code, so we've factored it out into a separate module.
  40  * Thus, we keep this grunge out of the other kvm applications (i.e.,
  41  * most other applications are interested only in open/close/read/nlist).
  42  */
  43
  44 #include <sys/param.h>
  45 #define _WANT_UCRED     /* make ucred.h give us 'struct ucred' */
  46 #include <sys/ucred.h>
  47 #include <sys/queue.h>
  48 #include <sys/_lock.h>
  49 #include <sys/_mutex.h>
  50 #include <sys/_task.h>
  51 #include <sys/cpuset.h>
  52 #include <sys/user.h>
  53 #include <sys/proc.h>
  54 #define _WANT_PRISON    /* make jail.h give us 'struct prison' */
  55 #include <sys/jail.h>
  56 #include <sys/exec.h>
  57 #include <sys/stat.h>
  58 #include <sys/sysent.h>
  59 #include <sys/ioctl.h>
  60 #include <sys/tty.h>
  61 #include <sys/file.h>
  62 #include <sys/conf.h>
  63 #define _WANT_KW_EXITCODE
  64 #include <sys/wait.h>
  65 #include <stdio.h>
  66 #include <stdlib.h>
  67 #include <stdbool.h>
  68 #include <unistd.h>
  69 #include <nlist.h>
  70 #include <kvm.h>
  71
  72 #include <sys/sysctl.h>
  73
  74 #include <limits.h>
  75 #include <memory.h>
  76 #include <paths.h>
  77
  78 #include "kvm_private.h"
  79
  80 #define KREAD(kd, addr, obj) \
  81         (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj))
  82
  83 static int ticks;
  84 static int hz;
  85 static uint64_t cpu_tick_frequency;
  86
  87 /*
  88  * From sys/kern/kern_tc.c. Depends on cpu_tick_frequency, which is
  89  * read/initialized before this function is ever called.
  90  */
  91 static uint64_t
  92 cputick2usec(uint64_t tick)
  93 {
  94         if (cpu_tick_frequency == 0)
  95                 return (0);
  96         return ((tick / cpu_tick_frequency) * 1000000ULL) +
  97             ((tick % cpu_tick_frequency) * 1000000ULL) / cpu_tick_frequency;
  98 }
  99
 100 /*
 101  * Read proc's from memory file into buffer bp, which has space to hold
 102  * at most maxcnt procs.
 103  */
 104 static int
 105 kvm_proclist(kvm_t *kd, int what, int arg, struct proc *p,
 106     struct kinfo_proc *bp, int maxcnt)
 107 {
 108         int cnt = 0;
 109         struct kinfo_proc kinfo_proc, *kp;
 110         struct pgrp pgrp;
 111         struct session sess;
 112         struct cdev t_cdev;
 113         struct tty tty;
 114         struct vmspace vmspace;
 115         struct sigacts sigacts;
 116 #if 0
 117         struct pstats pstats;
 118 #endif
 119         struct ucred ucred;
 120         struct prison pr;
 121         struct thread mtd;
 122         struct proc proc;
 123         struct proc pproc;
 124         struct sysentvec sysent;
 125         char svname[KI_EMULNAMELEN];
 126         struct thread *td = NULL;
 127         bool first_thread;
 128
 129         kp = &kinfo_proc;
 130         kp->ki_structsize = sizeof(kinfo_proc);
 131         /*
 132          * Loop on the processes, then threads within the process if requested.
 133          */
 134         if (what == KERN_PROC_ALL)
 135                 what |= KERN_PROC_INC_THREAD;
 136         for (; cnt < maxcnt && p != NULL; p = LIST_NEXT(&proc, p_list)) {
 137                 memset(kp, 0, sizeof *kp);
 138                 if (KREAD(kd, (u_long)p, &proc)) {
 139                         _kvm_err(kd, kd->program, "can't read proc at %p", p);
 140                         return (-1);
 141                 }
 142                 if (proc.p_state == PRS_NEW)
 143                         continue;
 144                 if (KREAD(kd, (u_long)proc.p_ucred, &ucred) == 0) {
 145                         kp->ki_ruid = ucred.cr_ruid;
 146                         kp->ki_svuid = ucred.cr_svuid;
 147                         kp->ki_rgid = ucred.cr_rgid;
 148                         kp->ki_svgid = ucred.cr_svgid;
 149                         kp->ki_cr_flags = ucred.cr_flags;
 150                         if (ucred.cr_ngroups > KI_NGROUPS) {
 151                                 kp->ki_ngroups = KI_NGROUPS;
 152                                 kp->ki_cr_flags |= KI_CRF_GRP_OVERFLOW;
 153                         } else
 154                                 kp->ki_ngroups = ucred.cr_ngroups;
 155                         kvm_read(kd, (u_long)ucred.cr_groups, kp->ki_groups,
 156                             kp->ki_ngroups * sizeof(gid_t));
 157                         kp->ki_uid = ucred.cr_uid;
 158                         if (ucred.cr_prison != NULL) {
 159                                 if (KREAD(kd, (u_long)ucred.cr_prison, &pr)) {
 160                                         _kvm_err(kd, kd->program,
 161                                             "can't read prison at %p",
 162                                             ucred.cr_prison);
 163                                         return (-1);
 164                                 }
 165                                 kp->ki_jid = pr.pr_id;
 166                         }
 167                 }
 168
 169                 switch(what & ~KERN_PROC_INC_THREAD) {
 170
 171                 case KERN_PROC_GID:
 172                         if (kp->ki_groups[0] != (gid_t)arg)
 173                                 continue;
 174                         break;
 175
 176                 case KERN_PROC_PID:
 177                         if (proc.p_pid != (pid_t)arg)
 178                                 continue;
 179                         break;
 180
 181                 case KERN_PROC_RGID:
 182                         if (kp->ki_rgid != (gid_t)arg)
 183                                 continue;
 184                         break;
 185
 186                 case KERN_PROC_UID:
 187                         if (kp->ki_uid != (uid_t)arg)
 188                                 continue;
 189                         break;
 190
 191                 case KERN_PROC_RUID:
 192                         if (kp->ki_ruid != (uid_t)arg)
 193                                 continue;
 194                         break;
 195                 }
 196                 /*
 197                  * We're going to add another proc to the set.  If this
 198                  * will overflow the buffer, assume the reason is because
 199                  * nprocs (or the proc list) is corrupt and declare an error.
 200                  */
 201                 if (cnt >= maxcnt) {
 202                         _kvm_err(kd, kd->program, "nprocs corrupt");
 203                         return (-1);
 204                 }
 205                 /*
 206                  * gather kinfo_proc
 207                  */
 208                 kp->ki_paddr = p;
 209                 kp->ki_addr = 0;        /* XXX uarea */
 210                 /* kp->ki_kstack = proc.p_thread.td_kstack; XXXKSE */
 211                 kp->ki_args = proc.p_args;
 212                 kp->ki_numthreads = proc.p_numthreads;
 213                 kp->ki_tracep = NULL;   /* XXXKIB do not expose ktr_io_params */
 214                 kp->ki_textvp = proc.p_textvp;
 215                 kp->ki_fd = proc.p_fd;
 216                 kp->ki_pd = proc.p_pd;
 217                 kp->ki_vmspace = proc.p_vmspace;
 218                 if (proc.p_sigacts != NULL) {
 219                         if (KREAD(kd, (u_long)proc.p_sigacts, &sigacts)) {
 220                                 _kvm_err(kd, kd->program,
 221                                     "can't read sigacts at %p", proc.p_sigacts);
 222                                 return (-1);
 223                         }
 224                         kp->ki_sigignore = sigacts.ps_sigignore;
 225                         kp->ki_sigcatch = sigacts.ps_sigcatch;
 226                 }
 227 #if 0
 228                 if ((proc.p_flag & P_INMEM) && proc.p_stats != NULL) {
 229                         if (KREAD(kd, (u_long)proc.p_stats, &pstats)) {
 230                                 _kvm_err(kd, kd->program,
 231                                     "can't read stats at %x", proc.p_stats);
 232                                 return (-1);
 233                         }
 234                         kp->ki_start = pstats.p_start;
 235
 236                         /*
 237                          * XXX: The times here are probably zero and need
 238                          * to be calculated from the raw data in p_rux and
 239                          * p_crux.
 240                          */
 241                         kp->ki_rusage = pstats.p_ru;
 242                         kp->ki_childstime = pstats.p_cru.ru_stime;
 243                         kp->ki_childutime = pstats.p_cru.ru_utime;
 244                         /* Some callers want child-times in a single value */
 245                         timeradd(&kp->ki_childstime, &kp->ki_childutime,
 246                             &kp->ki_childtime);
 247                 }
 248 #endif
 249                 if (proc.p_oppid)
 250                         kp->ki_ppid = proc.p_oppid;
 251                 else if (proc.p_pptr) {
 252                         if (KREAD(kd, (u_long)proc.p_pptr, &pproc)) {
 253                                 _kvm_err(kd, kd->program,
 254                                     "can't read pproc at %p", proc.p_pptr);
 255                                 return (-1);
 256                         }
 257                         kp->ki_ppid = pproc.p_pid;
 258                 } else
 259                         kp->ki_ppid = 0;
 260                 if (proc.p_pgrp == NULL)
 261                         goto nopgrp;
 262                 if (KREAD(kd, (u_long)proc.p_pgrp, &pgrp)) {
 263                         _kvm_err(kd, kd->program, "can't read pgrp at %p",
 264                                  proc.p_pgrp);
 265                         return (-1);
 266                 }
 267                 kp->ki_pgid = pgrp.pg_id;
 268                 kp->ki_jobc = -1;       /* Or calculate?  Arguably not. */
 269                 if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) {
 270                         _kvm_err(kd, kd->program, "can't read session at %p",
 271                                 pgrp.pg_session);
 272                         return (-1);
 273                 }
 274                 kp->ki_sid = sess.s_sid;
 275                 (void)memcpy(kp->ki_login, sess.s_login,
 276                                                 sizeof(kp->ki_login));
 277                 if ((proc.p_flag & P_CONTROLT) && sess.s_ttyp != NULL) {
 278                         if (KREAD(kd, (u_long)sess.s_ttyp, &tty)) {
 279                                 _kvm_err(kd, kd->program,
 280                                          "can't read tty at %p", sess.s_ttyp);
 281                                 return (-1);
 282                         }
 283                         if (tty.t_dev != NULL) {
 284                                 if (KREAD(kd, (u_long)tty.t_dev, &t_cdev)) {
 285                                         _kvm_err(kd, kd->program,
 286                                                  "can't read cdev at %p",
 287                                                 tty.t_dev);
 288                                         return (-1);
 289                                 }
 290 #if 0
 291                                 kp->ki_tdev = t_cdev.si_udev;
 292 #else
 293                                 kp->ki_tdev = NODEV;
 294 #endif
 295                         }
 296                         if (tty.t_pgrp != NULL) {
 297                                 if (KREAD(kd, (u_long)tty.t_pgrp, &pgrp)) {
 298                                         _kvm_err(kd, kd->program,
 299                                                  "can't read tpgrp at %p",
 300                                                 tty.t_pgrp);
 301                                         return (-1);
 302                                 }
 303                                 kp->ki_tpgid = pgrp.pg_id;
 304                         } else
 305                                 kp->ki_tpgid = -1;
 306                         if (tty.t_session != NULL) {
 307                                 if (KREAD(kd, (u_long)tty.t_session, &sess)) {
 308                                         _kvm_err(kd, kd->program,
 309                                             "can't read session at %p",
 310                                             tty.t_session);
 311                                         return (-1);
 312                                 }
 313                                 kp->ki_tsid = sess.s_sid;
 314                         }
 315                 } else {
 316 nopgrp:
 317                         kp->ki_tdev = NODEV;
 318                 }
 319
 320                 (void)kvm_read(kd, (u_long)proc.p_vmspace,
 321                     (char *)&vmspace, sizeof(vmspace));
 322                 kp->ki_size = vmspace.vm_map.size;
 323                 /*
 324                  * Approximate the kernel's method of calculating
 325                  * this field.
 326                  */
 327 #define         pmap_resident_count(pm) ((pm)->pm_stats.resident_count)
 328                 kp->ki_rssize = pmap_resident_count(&vmspace.vm_pmap);
 329                 kp->ki_swrss = vmspace.vm_swrss;
 330                 kp->ki_tsize = vmspace.vm_tsize;
 331                 kp->ki_dsize = vmspace.vm_dsize;
 332                 kp->ki_ssize = vmspace.vm_ssize;
 333
 334                 switch (what & ~KERN_PROC_INC_THREAD) {
 335
 336                 case KERN_PROC_PGRP:
 337                         if (kp->ki_pgid != (pid_t)arg)
 338                                 continue;
 339                         break;
 340
 341                 case KERN_PROC_SESSION:
 342                         if (kp->ki_sid != (pid_t)arg)
 343                                 continue;
 344                         break;
 345
 346                 case KERN_PROC_TTY:
 347                         if ((proc.p_flag & P_CONTROLT) == 0 ||
 348                              kp->ki_tdev != (dev_t)arg)
 349                                 continue;
 350                         break;
 351                 }
 352                 if (proc.p_comm[0] != 0)
 353                         strlcpy(kp->ki_comm, proc.p_comm, MAXCOMLEN);
 354                 (void)kvm_read(kd, (u_long)proc.p_sysent, (char *)&sysent,
 355                     sizeof(sysent));
 356                 (void)kvm_read(kd, (u_long)sysent.sv_name, (char *)&svname,
 357                     sizeof(svname));
 358                 if (svname[0] != 0)
 359                         strlcpy(kp->ki_emul, svname, KI_EMULNAMELEN);
 360                 kp->ki_runtime = cputick2usec(proc.p_rux.rux_runtime);
 361                 kp->ki_pid = proc.p_pid;
 362                 kp->ki_xstat = KW_EXITCODE(proc.p_xexit, proc.p_xsig);
 363                 kp->ki_acflag = proc.p_acflag;
 364                 kp->ki_lock = proc.p_lock;
 365                 kp->ki_tdev_freebsd11 = kp->ki_tdev; /* truncate */
 366
 367                 /* Per-thread items; iterate as appropriate. */
 368                 td = TAILQ_FIRST(&proc.p_threads);
 369                 for (first_thread = true; cnt < maxcnt && td != NULL &&
 370                     (first_thread || (what & KERN_PROC_INC_THREAD));
 371                     first_thread = false) {
 372                         if (proc.p_state != PRS_ZOMBIE) {
 373                                 if (KREAD(kd, (u_long)td, &mtd)) {
 374                                         _kvm_err(kd, kd->program,
 375                                             "can't read thread at %p", td);
 376                                         return (-1);
 377                                 }
 378                                 if (what & KERN_PROC_INC_THREAD)
 379                                         td = TAILQ_NEXT(&mtd, td_plist);
 380                         } else
 381                                 td = NULL;
 382                         if ((proc.p_state != PRS_ZOMBIE) && mtd.td_wmesg)
 383                                 (void)kvm_read(kd, (u_long)mtd.td_wmesg,
 384                                     kp->ki_wmesg, WMESGLEN);
 385                         else
 386                                 memset(kp->ki_wmesg, 0, WMESGLEN);
 387                         if (proc.p_pgrp == NULL) {
 388                                 kp->ki_kiflag = 0;
 389                         } else {
 390                                 kp->ki_kiflag = sess.s_ttyvp ? KI_CTTY : 0;
 391                                 if (sess.s_leader == p)
 392                                         kp->ki_kiflag |= KI_SLEADER;
 393                         }
 394                         if ((proc.p_state != PRS_ZOMBIE) &&
 395                             (mtd.td_blocked != 0)) {
 396                                 kp->ki_kiflag |= KI_LOCKBLOCK;
 397                                 if (mtd.td_lockname)
 398                                         (void)kvm_read(kd,
 399                                             (u_long)mtd.td_lockname,
 400                                             kp->ki_lockname, LOCKNAMELEN);
 401                                 else
 402                                         memset(kp->ki_lockname, 0,
 403                                             LOCKNAMELEN);
 404                                 kp->ki_lockname[LOCKNAMELEN] = 0;
 405                         } else
 406                                 kp->ki_kiflag &= ~KI_LOCKBLOCK;
 407                         kp->ki_siglist = proc.p_siglist;
 408                         if (proc.p_state != PRS_ZOMBIE) {
 409                                 SIGSETOR(kp->ki_siglist, mtd.td_siglist);
 410                                 kp->ki_sigmask = mtd.td_sigmask;
 411                                 kp->ki_swtime = (ticks - proc.p_swtick) / hz;
 412                                 kp->ki_flag = proc.p_flag;
 413                                 kp->ki_sflag = 0;
 414                                 kp->ki_nice = proc.p_nice;
 415                                 kp->ki_traceflag = proc.p_traceflag;
 416                                 if (proc.p_state == PRS_NORMAL) {
 417                                         if (TD_ON_RUNQ(&mtd) ||
 418                                             TD_CAN_RUN(&mtd) ||
 419                                             TD_IS_RUNNING(&mtd)) {
 420                                                 kp->ki_stat = SRUN;
 421                                         } else if (TD_GET_STATE(&mtd) ==
 422                                             TDS_INHIBITED) {
 423                                                 if (P_SHOULDSTOP(&proc)) {
 424                                                         kp->ki_stat = SSTOP;
 425                                                 } else if (
 426                                                     TD_IS_SLEEPING(&mtd)) {
 427                                                         kp->ki_stat = SSLEEP;
 428                                                 } else if (TD_ON_LOCK(&mtd)) {
 429                                                         kp->ki_stat = SLOCK;
 430                                                 } else {
 431                                                         kp->ki_stat = SWAIT;
 432                                                 }
 433                                         }
 434                                 } else {
 435                                         kp->ki_stat = SIDL;
 436                                 }
 437                                 /* Stuff from the thread */
 438                                 kp->ki_pri.pri_level = mtd.td_priority;
 439                                 kp->ki_pri.pri_native = mtd.td_base_pri;
 440                                 kp->ki_lastcpu = mtd.td_lastcpu;
 441                                 kp->ki_wchan = mtd.td_wchan;
 442                                 kp->ki_oncpu = mtd.td_oncpu;
 443                                 if (mtd.td_name[0] != '\0')
 444                                         strlcpy(kp->ki_tdname, mtd.td_name,
 445                                             sizeof(kp->ki_tdname));
 446                                 else
 447                                         memset(kp->ki_tdname, 0,
 448                                             sizeof(kp->ki_tdname));
 449                                 kp->ki_pctcpu = 0;
 450                                 kp->ki_rqindex = 0;
 451
 452                                 /*
 453                                  * Note: legacy fields; wraps at NO_CPU_OLD
 454                                  * or the old max CPU value as appropriate
 455                                  */
 456                                 if (mtd.td_lastcpu == NOCPU)
 457                                         kp->ki_lastcpu_old = NOCPU_OLD;
 458                                 else if (mtd.td_lastcpu > MAXCPU_OLD)
 459                                         kp->ki_lastcpu_old = MAXCPU_OLD;
 460                                 else
 461                                         kp->ki_lastcpu_old = mtd.td_lastcpu;
 462
 463                                 if (mtd.td_oncpu == NOCPU)
 464                                         kp->ki_oncpu_old = NOCPU_OLD;
 465                                 else if (mtd.td_oncpu > MAXCPU_OLD)
 466                                         kp->ki_oncpu_old = MAXCPU_OLD;
 467                                 else
 468                                         kp->ki_oncpu_old = mtd.td_oncpu;
 469                                 kp->ki_tid = mtd.td_tid;
 470                         } else {
 471                                 memset(&kp->ki_sigmask, 0,
 472                                     sizeof(kp->ki_sigmask));
 473                                 kp->ki_stat = SZOMB;
 474                                 kp->ki_tid = 0;
 475                         }
 476
 477                         bcopy(&kinfo_proc, bp, sizeof(kinfo_proc));
 478                         ++bp;
 479                         ++cnt;
 480                 }
 481         }
 482         return (cnt);
 483 }
 484
 485 /*
 486  * Build proc info array by reading in proc list from a crash dump.
 487  * Return number of procs read.  maxcnt is the max we will read.
 488  */
 489 static int
 490 kvm_deadprocs(kvm_t *kd, int what, int arg, u_long a_allproc,
 491     u_long a_zombproc, int maxcnt)
 492 {
 493         struct kinfo_proc *bp = kd->procbase;
 494         int acnt, zcnt = 0;
 495         struct proc *p;
 496
 497         if (KREAD(kd, a_allproc, &p)) {
 498                 _kvm_err(kd, kd->program, "cannot read allproc");
 499                 return (-1);
 500         }
 501         acnt = kvm_proclist(kd, what, arg, p, bp, maxcnt);
 502         if (acnt < 0)
 503                 return (acnt);
 504
 505         if (a_zombproc != 0) {
 506                 if (KREAD(kd, a_zombproc, &p)) {
 507                         _kvm_err(kd, kd->program, "cannot read zombproc");
 508                         return (-1);
 509                 }
 510                 zcnt = kvm_proclist(kd, what, arg, p, bp + acnt, maxcnt - acnt);
 511                 if (zcnt < 0)
 512                         zcnt = 0;
 513         }
 514
 515         return (acnt + zcnt);
 516 }
 517
 518 struct kinfo_proc *
 519 kvm_getprocs(kvm_t *kd, int op, int arg, int *cnt)
 520 {
 521         int mib[4], st, nprocs;
 522         size_t size, osize;
 523         int temp_op;
 524
 525         if (kd->procbase != 0) {
 526                 free((void *)kd->procbase);
 527                 /*
 528                  * Clear this pointer in case this call fails.  Otherwise,
 529                  * kvm_close() will free it again.
 530                  */
 531                 kd->procbase = 0;
 532         }
 533         if (ISALIVE(kd)) {
 534                 size = 0;
 535                 mib[0] = CTL_KERN;
 536                 mib[1] = KERN_PROC;
 537                 mib[2] = op;
 538                 mib[3] = arg;
 539                 temp_op = op & ~KERN_PROC_INC_THREAD;
 540                 st = sysctl(mib,
 541                     temp_op == KERN_PROC_ALL || temp_op == KERN_PROC_PROC ?
 542                     3 : 4, NULL, &size, NULL, 0);
 543                 if (st == -1) {
 544                         _kvm_syserr(kd, kd->program, "kvm_getprocs");
 545                         return (0);
 546                 }
 547                 /*
 548                  * We can't continue with a size of 0 because we pass
 549                  * it to realloc() (via _kvm_realloc()), and passing 0
 550                  * to realloc() results in undefined behavior.
 551                  */
 552                 if (size == 0) {
 553                         /*
 554                          * XXX: We should probably return an invalid,
 555                          * but non-NULL, pointer here so any client
 556                          * program trying to dereference it will
 557                          * crash.  However, _kvm_freeprocs() calls
 558                          * free() on kd->procbase if it isn't NULL,
 559                          * and free()'ing a junk pointer isn't good.
 560                          * Then again, _kvm_freeprocs() isn't used
 561                          * anywhere . . .
 562                          */
 563                         kd->procbase = _kvm_malloc(kd, 1);
 564                         goto liveout;
 565                 }
 566                 do {
 567                         size += size / 10;
 568                         kd->procbase = (struct kinfo_proc *)
 569                             _kvm_realloc(kd, kd->procbase, size);
 570                         if (kd->procbase == NULL)
 571                                 return (0);
 572                         osize = size;
 573                         st = sysctl(mib, temp_op == KERN_PROC_ALL ||
 574                             temp_op == KERN_PROC_PROC ? 3 : 4,
 575                             kd->procbase, &size, NULL, 0);
 576                 } while (st == -1 && errno == ENOMEM && size == osize);
 577                 if (st == -1) {
 578                         _kvm_syserr(kd, kd->program, "kvm_getprocs");
 579                         return (0);
 580                 }
 581                 /*
 582                  * We have to check the size again because sysctl()
 583                  * may "round up" oldlenp if oldp is NULL; hence it
 584                  * might've told us that there was data to get when
 585                  * there really isn't any.
 586                  */
 587                 if (size > 0 &&
 588                     kd->procbase->ki_structsize != sizeof(struct kinfo_proc)) {
 589                         _kvm_err(kd, kd->program,
 590                             "kinfo_proc size mismatch (expected %zu, got %d)",
 591                             sizeof(struct kinfo_proc),
 592                             kd->procbase->ki_structsize);
 593                         return (0);
 594                 }
 595 liveout:
 596                 nprocs = size == 0 ? 0 : size / kd->procbase->ki_structsize;
 597         } else {
 598                 struct nlist nl[6], *p;
 599                 struct nlist nlz[2];
 600
 601                 nl[0].n_name = "_nprocs";
 602                 nl[1].n_name = "_allproc";
 603                 nl[2].n_name = "_ticks";
 604                 nl[3].n_name = "_hz";
 605                 nl[4].n_name = "_cpu_tick_frequency";
 606                 nl[5].n_name = 0;
 607
 608                 nlz[0].n_name = "_zombproc";
 609                 nlz[1].n_name = 0;
 610
 611                 if (!kd->arch->ka_native(kd)) {
 612                         _kvm_err(kd, kd->program,
 613                             "cannot read procs from non-native core");
 614                         return (0);
 615                 }
 616
 617                 if (kvm_nlist(kd, nl) != 0) {
 618                         for (p = nl; p->n_type != 0; ++p)
 619                                 ;
 620                         _kvm_err(kd, kd->program,
 621                                  "%s: no such symbol", p->n_name);
 622                         return (0);
 623                 }
 624                 (void) kvm_nlist(kd, nlz);      /* attempt to get zombproc */
 625                 if (KREAD(kd, nl[0].n_value, &nprocs)) {
 626                         _kvm_err(kd, kd->program, "can't read nprocs");
 627                         return (0);
 628                 }
 629                 /*
 630                  * If returning all threads, we don't know how many that
 631                  * might be.  Presume that there are, on average, no more
 632                  * than 10 threads per process.
 633                  */
 634                 if (op == KERN_PROC_ALL || (op & KERN_PROC_INC_THREAD))
 635                         nprocs *= 10;           /* XXX */
 636                 if (KREAD(kd, nl[2].n_value, &ticks)) {
 637                         _kvm_err(kd, kd->program, "can't read ticks");
 638                         return (0);
 639                 }
 640                 if (KREAD(kd, nl[3].n_value, &hz)) {
 641                         _kvm_err(kd, kd->program, "can't read hz");
 642                         return (0);
 643                 }
 644                 if (KREAD(kd, nl[4].n_value, &cpu_tick_frequency)) {
 645                         _kvm_err(kd, kd->program,
 646                             "can't read cpu_tick_frequency");
 647                         return (0);
 648                 }
 649                 size = nprocs * sizeof(struct kinfo_proc);
 650                 kd->procbase = (struct kinfo_proc *)_kvm_malloc(kd, size);
 651                 if (kd->procbase == NULL)
 652                         return (0);
 653
 654                 nprocs = kvm_deadprocs(kd, op, arg, nl[1].n_value,
 655                                       nlz[0].n_value, nprocs);
 656                 if (nprocs <= 0) {
 657                         _kvm_freeprocs(kd);
 658                         nprocs = 0;
 659                 }
 660 #ifdef notdef
 661                 else {
 662                         size = nprocs * sizeof(struct kinfo_proc);
 663                         kd->procbase = realloc(kd->procbase, size);
 664                 }
 665 #endif
 666         }
 667         *cnt = nprocs;
 668         return (kd->procbase);
 669 }
 670
 671 void
 672 _kvm_freeprocs(kvm_t *kd)
 673 {
 674
 675         free(kd->procbase);
 676         kd->procbase = NULL;
 677 }
 678
 679 void *
 680 _kvm_realloc(kvm_t *kd, void *p, size_t n)
 681 {
 682         void *np;
 683
 684         np = reallocf(p, n);
 685         if (np == NULL)
 686                 _kvm_err(kd, kd->program, "out of memory");
 687         return (np);
 688 }
 689
 690 /*
 691  * Get the command args or environment.
 692  */
 693 static char **
 694 kvm_argv(kvm_t *kd, const struct kinfo_proc *kp, int env, int nchr)
 695 {
 696         int oid[4];
 697         int i;
 698         size_t bufsz;
 699         static int buflen;
 700         static char *buf, *p;
 701         static char **bufp;
 702         static int argc;
 703         char **nbufp;
 704
 705         if (!ISALIVE(kd)) {
 706                 _kvm_err(kd, kd->program,
 707                     "cannot read user space from dead kernel");
 708                 return (NULL);
 709         }
 710
 711         if (nchr == 0 || nchr > ARG_MAX)
 712                 nchr = ARG_MAX;
 713         if (buflen == 0) {
 714                 buf = malloc(nchr);
 715                 if (buf == NULL) {
 716                         _kvm_err(kd, kd->program, "cannot allocate memory");
 717                         return (NULL);
 718                 }
 719                 argc = 32;
 720                 bufp = malloc(sizeof(char *) * argc);
 721                 if (bufp == NULL) {
 722                         free(buf);
 723                         buf = NULL;
 724                         _kvm_err(kd, kd->program, "cannot allocate memory");
 725                         return (NULL);
 726                 }
 727                 buflen = nchr;
 728         } else if (nchr > buflen) {
 729                 p = realloc(buf, nchr);
 730                 if (p != NULL) {
 731                         buf = p;
 732                         buflen = nchr;
 733                 }
 734         }
 735         oid[0] = CTL_KERN;
 736         oid[1] = KERN_PROC;
 737         oid[2] = env ? KERN_PROC_ENV : KERN_PROC_ARGS;
 738         oid[3] = kp->ki_pid;
 739         bufsz = buflen;
 740         if (sysctl(oid, 4, buf, &bufsz, 0, 0) == -1) {
 741                 /*
 742                  * If the supplied buf is too short to hold the requested
 743                  * value the sysctl returns with ENOMEM. The buf is filled
 744                  * with the truncated value and the returned bufsz is equal
 745                  * to the requested len.
 746                  */
 747                 if (errno != ENOMEM || bufsz != (size_t)buflen)
 748                         return (NULL);
 749                 buf[bufsz - 1] = '\0';
 750                 errno = 0;
 751         } else if (bufsz == 0)
 752                 return (NULL);
 753         i = 0;
 754         p = buf;
 755         do {
 756                 bufp[i++] = p;
 757                 p += strlen(p) + 1;
 758                 if (i >= argc) {
 759                         argc += argc;
 760                         nbufp = realloc(bufp, sizeof(char *) * argc);
 761                         if (nbufp == NULL)
 762                                 return (NULL);
 763                         bufp = nbufp;
 764                 }
 765         } while (p < buf + bufsz);
 766         bufp[i++] = 0;
 767         return (bufp);
 768 }
 769
 770 char **
 771 kvm_getargv(kvm_t *kd, const struct kinfo_proc *kp, int nchr)
 772 {
 773         return (kvm_argv(kd, kp, 0, nchr));
 774 }
 775
 776 char **
 777 kvm_getenvv(kvm_t *kd, const struct kinfo_proc *kp, int nchr)
 778 {
 779         return (kvm_argv(kd, kp, 1, nchr));
 780 }