kvm_proc.c revision 1.19
1 /* $NetBSD: kvm_proc.c,v 1.19 1997/08/15 02:22:02 mikel Exp $ */ 2 3 /*- 4 * Copyright (c) 1994, 1995 Charles M. Hannum. All rights reserved. 5 * Copyright (c) 1989, 1992, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software developed by the Computer Systems 9 * Engineering group at Lawrence Berkeley Laboratory under DARPA contract 10 * BG 91-66 and contributed to Berkeley. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 */ 40 41 #include <sys/cdefs.h> 42 #if defined(LIBC_SCCS) && !defined(lint) 43 #if 0 44 static char sccsid[] = "@(#)kvm_proc.c 8.3 (Berkeley) 9/23/93"; 45 #else 46 __RCSID("$NetBSD: kvm_proc.c,v 1.19 1997/08/15 02:22:02 mikel Exp $"); 47 #endif 48 #endif /* LIBC_SCCS and not lint */ 49 50 /* 51 * Proc traversal interface for kvm. ps and w are (probably) the exclusive 52 * users of this code, so we've factored it out into a separate module. 53 * Thus, we keep this grunge out of the other kvm applications (i.e., 54 * most other applications are interested only in open/close/read/nlist). 55 */ 56 57 #include <sys/param.h> 58 #include <sys/user.h> 59 #include <sys/proc.h> 60 #include <sys/exec.h> 61 #include <sys/stat.h> 62 #include <sys/ioctl.h> 63 #include <sys/tty.h> 64 #include <stdlib.h> 65 #include <string.h> 66 #include <unistd.h> 67 #include <nlist.h> 68 #include <kvm.h> 69 70 #include <vm/vm.h> 71 #include <vm/vm_param.h> 72 #include <vm/swap_pager.h> 73 74 #include <sys/sysctl.h> 75 76 #include <limits.h> 77 #include <db.h> 78 #include <paths.h> 79 80 #include "kvm_private.h" 81 82 #define KREAD(kd, addr, obj) \ 83 (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj)) 84 85 int _kvm_readfromcore __P((kvm_t *, u_long, u_long)); 86 int _kvm_readfrompager __P((kvm_t *, struct vm_object *, u_long)); 87 ssize_t kvm_uread __P((kvm_t *, const struct proc *, u_long, char *, 88 size_t)); 89 90 static char **kvm_argv __P((kvm_t *, const struct proc *, u_long, int, 91 int)); 92 static int kvm_deadprocs __P((kvm_t *, int, int, u_long, u_long, int)); 93 static char **kvm_doargv __P((kvm_t *, const struct kinfo_proc *, int, 94 void (*)(struct ps_strings *, u_long *, int *))); 95 static int kvm_proclist __P((kvm_t *, int, int, struct proc *, 96 struct kinfo_proc *, int)); 97 static int proc_verify __P((kvm_t *, u_long, const struct proc *)); 98 static void ps_str_a __P((struct ps_strings *, u_long *, int *)); 99 static void ps_str_e __P((struct ps_strings *, u_long *, int *)); 100 101 char * 102 _kvm_uread(kd, p, va, cnt) 103 kvm_t *kd; 104 const struct proc *p; 105 u_long va; 106 u_long *cnt; 107 { 108 register u_long addr, head; 109 register u_long offset; 110 struct vm_map_entry vme; 111 struct vm_object vmo; 112 int rv; 113 114 if (kd->swapspc == 0) { 115 kd->swapspc = (char *)_kvm_malloc(kd, kd->nbpg); 116 if (kd->swapspc == 0) 117 return (0); 118 } 119 120 /* 121 * Look through the address map for the memory object 122 * that corresponds to the given virtual address. 123 * The header just has the entire valid range. 124 */ 125 head = (u_long)&p->p_vmspace->vm_map.header; 126 addr = head; 127 while (1) { 128 if (KREAD(kd, addr, &vme)) 129 return (0); 130 131 if (va >= vme.start && va < vme.end && 132 vme.object.vm_object != 0) 133 break; 134 135 addr = (u_long)vme.next; 136 if (addr == head) 137 return (0); 138 } 139 140 /* 141 * We found the right object -- follow shadow links. 142 */ 143 offset = va - vme.start + vme.offset; 144 addr = (u_long)vme.object.vm_object; 145 146 while (1) { 147 /* Try reading the page from core first. */ 148 if ((rv = _kvm_readfromcore(kd, addr, offset))) 149 break; 150 151 if (KREAD(kd, addr, &vmo)) 152 return (0); 153 154 /* If there is a pager here, see if it has the page. */ 155 if (vmo.pager != 0 && 156 (rv = _kvm_readfrompager(kd, &vmo, offset))) 157 break; 158 159 /* Move down the shadow chain. */ 160 addr = (u_long)vmo.shadow; 161 if (addr == 0) 162 return (0); 163 offset += vmo.shadow_offset; 164 } 165 166 if (rv == -1) 167 return (0); 168 169 /* Found the page. */ 170 offset %= kd->nbpg; 171 *cnt = kd->nbpg - offset; 172 return (&kd->swapspc[offset]); 173 } 174 175 #define vm_page_hash(kd, object, offset) \ 176 (((u_long)object + (u_long)(offset / kd->nbpg)) & kd->vm_page_hash_mask) 177 178 int 179 _kvm_coreinit(kd) 180 kvm_t *kd; 181 { 182 struct nlist nlist[3]; 183 184 nlist[0].n_name = "_vm_page_buckets"; 185 nlist[1].n_name = "_vm_page_hash_mask"; 186 nlist[2].n_name = 0; 187 if (kvm_nlist(kd, nlist) != 0) 188 return (-1); 189 190 if (KREAD(kd, nlist[0].n_value, &kd->vm_page_buckets) || 191 KREAD(kd, nlist[1].n_value, &kd->vm_page_hash_mask)) 192 return (-1); 193 194 return (0); 195 } 196 197 int 198 _kvm_readfromcore(kd, object, offset) 199 kvm_t *kd; 200 u_long object, offset; 201 { 202 u_long addr; 203 struct pglist bucket; 204 struct vm_page mem; 205 off_t seekpoint; 206 207 if (kd->vm_page_buckets == 0 && 208 _kvm_coreinit(kd)) 209 return (-1); 210 211 addr = (u_long)&kd->vm_page_buckets[vm_page_hash(kd, object, offset)]; 212 if (KREAD(kd, addr, &bucket)) 213 return (-1); 214 215 addr = (u_long)bucket.tqh_first; 216 offset &= ~(kd->nbpg -1); 217 while (1) { 218 if (addr == 0) 219 return (0); 220 221 if (KREAD(kd, addr, &mem)) 222 return (-1); 223 224 if ((u_long)mem.object == object && 225 (u_long)mem.offset == offset) 226 break; 227 228 addr = (u_long)mem.hashq.tqe_next; 229 } 230 231 seekpoint = mem.phys_addr; 232 233 if (lseek(kd->pmfd, seekpoint, 0) == -1) 234 return (-1); 235 if (read(kd->pmfd, kd->swapspc, kd->nbpg) != kd->nbpg) 236 return (-1); 237 238 return (1); 239 } 240 241 int 242 _kvm_readfrompager(kd, vmop, offset) 243 kvm_t *kd; 244 struct vm_object *vmop; 245 u_long offset; 246 { 247 u_long addr; 248 struct pager_struct pager; 249 struct swpager swap; 250 int ix; 251 struct swblock swb; 252 off_t seekpoint; 253 254 /* Read in the pager info and make sure it's a swap device. */ 255 addr = (u_long)vmop->pager; 256 if (KREAD(kd, addr, &pager) || pager.pg_type != PG_SWAP) 257 return (-1); 258 259 /* Read in the swap_pager private data. */ 260 addr = (u_long)pager.pg_data; 261 if (KREAD(kd, addr, &swap)) 262 return (-1); 263 264 /* 265 * Calculate the paging offset, and make sure it's within the 266 * bounds of the pager. 267 */ 268 offset += vmop->paging_offset; 269 ix = offset / dbtob(swap.sw_bsize); 270 #if 0 271 if (swap.sw_blocks == 0 || ix >= swap.sw_nblocks) 272 return (-1); 273 #else 274 if (swap.sw_blocks == 0 || ix >= swap.sw_nblocks) { 275 int i; 276 printf("BUG BUG BUG BUG:\n"); 277 printf("object %p offset %lx pgoffset %lx ", 278 vmop, offset - vmop->paging_offset, 279 (u_long)vmop->paging_offset); 280 printf("pager %p swpager %p\n", 281 vmop->pager, pager.pg_data); 282 printf("osize %lx bsize %x blocks %p nblocks %x\n", 283 (u_long)swap.sw_osize, swap.sw_bsize, swap.sw_blocks, 284 swap.sw_nblocks); 285 for (ix = 0; ix < swap.sw_nblocks; ix++) { 286 addr = (u_long)&swap.sw_blocks[ix]; 287 if (KREAD(kd, addr, &swb)) 288 return (0); 289 printf("sw_blocks[%d]: block %x mask %x\n", ix, 290 swb.swb_block, swb.swb_mask); 291 } 292 return (-1); 293 } 294 #endif 295 296 /* Read in the swap records. */ 297 addr = (u_long)&swap.sw_blocks[ix]; 298 if (KREAD(kd, addr, &swb)) 299 return (-1); 300 301 /* Calculate offset within pager. */ 302 offset %= dbtob(swap.sw_bsize); 303 304 /* Check that the page is actually present. */ 305 if ((swb.swb_mask & (1 << (offset / kd->nbpg))) == 0) 306 return (0); 307 308 if (!ISALIVE(kd)) 309 return (-1); 310 311 /* Calculate the physical address and read the page. */ 312 seekpoint = dbtob(swb.swb_block) + (offset & ~(kd->nbpg -1)); 313 314 if (lseek(kd->swfd, seekpoint, 0) == -1) 315 return (-1); 316 if (read(kd->swfd, kd->swapspc, kd->nbpg) != kd->nbpg) 317 return (-1); 318 319 return (1); 320 } 321 322 /* 323 * Read proc's from memory file into buffer bp, which has space to hold 324 * at most maxcnt procs. 325 */ 326 static int 327 kvm_proclist(kd, what, arg, p, bp, maxcnt) 328 kvm_t *kd; 329 int what, arg; 330 struct proc *p; 331 struct kinfo_proc *bp; 332 int maxcnt; 333 { 334 register int cnt = 0; 335 struct eproc eproc; 336 struct pgrp pgrp; 337 struct session sess; 338 struct tty tty; 339 struct proc proc; 340 341 for (; cnt < maxcnt && p != NULL; p = proc.p_list.le_next) { 342 if (KREAD(kd, (u_long)p, &proc)) { 343 _kvm_err(kd, kd->program, "can't read proc at %x", p); 344 return (-1); 345 } 346 if (KREAD(kd, (u_long)proc.p_cred, &eproc.e_pcred) == 0) 347 KREAD(kd, (u_long)eproc.e_pcred.pc_ucred, 348 &eproc.e_ucred); 349 350 switch(what) { 351 352 case KERN_PROC_PID: 353 if (proc.p_pid != (pid_t)arg) 354 continue; 355 break; 356 357 case KERN_PROC_UID: 358 if (eproc.e_ucred.cr_uid != (uid_t)arg) 359 continue; 360 break; 361 362 case KERN_PROC_RUID: 363 if (eproc.e_pcred.p_ruid != (uid_t)arg) 364 continue; 365 break; 366 } 367 /* 368 * We're going to add another proc to the set. If this 369 * will overflow the buffer, assume the reason is because 370 * nprocs (or the proc list) is corrupt and declare an error. 371 */ 372 if (cnt >= maxcnt) { 373 _kvm_err(kd, kd->program, "nprocs corrupt"); 374 return (-1); 375 } 376 /* 377 * gather eproc 378 */ 379 eproc.e_paddr = p; 380 if (KREAD(kd, (u_long)proc.p_pgrp, &pgrp)) { 381 _kvm_err(kd, kd->program, "can't read pgrp at %x", 382 proc.p_pgrp); 383 return (-1); 384 } 385 eproc.e_sess = pgrp.pg_session; 386 eproc.e_pgid = pgrp.pg_id; 387 eproc.e_jobc = pgrp.pg_jobc; 388 if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) { 389 _kvm_err(kd, kd->program, "can't read session at %x", 390 pgrp.pg_session); 391 return (-1); 392 } 393 if ((proc.p_flag & P_CONTROLT) && sess.s_ttyp != NULL) { 394 if (KREAD(kd, (u_long)sess.s_ttyp, &tty)) { 395 _kvm_err(kd, kd->program, 396 "can't read tty at %x", sess.s_ttyp); 397 return (-1); 398 } 399 eproc.e_tdev = tty.t_dev; 400 eproc.e_tsess = tty.t_session; 401 if (tty.t_pgrp != NULL) { 402 if (KREAD(kd, (u_long)tty.t_pgrp, &pgrp)) { 403 _kvm_err(kd, kd->program, 404 "can't read tpgrp at &x", 405 tty.t_pgrp); 406 return (-1); 407 } 408 eproc.e_tpgid = pgrp.pg_id; 409 } else 410 eproc.e_tpgid = -1; 411 } else 412 eproc.e_tdev = NODEV; 413 eproc.e_flag = sess.s_ttyvp ? EPROC_CTTY : 0; 414 if (sess.s_leader == p) 415 eproc.e_flag |= EPROC_SLEADER; 416 if (proc.p_wmesg) 417 (void)kvm_read(kd, (u_long)proc.p_wmesg, 418 eproc.e_wmesg, WMESGLEN); 419 420 (void)kvm_read(kd, (u_long)proc.p_vmspace, 421 (char *)&eproc.e_vm, sizeof(eproc.e_vm)); 422 423 eproc.e_xsize = eproc.e_xrssize = 0; 424 eproc.e_xccount = eproc.e_xswrss = 0; 425 426 switch (what) { 427 428 case KERN_PROC_PGRP: 429 if (eproc.e_pgid != (pid_t)arg) 430 continue; 431 break; 432 433 case KERN_PROC_TTY: 434 if ((proc.p_flag & P_CONTROLT) == 0 || 435 eproc.e_tdev != (dev_t)arg) 436 continue; 437 break; 438 } 439 bcopy(&proc, &bp->kp_proc, sizeof(proc)); 440 bcopy(&eproc, &bp->kp_eproc, sizeof(eproc)); 441 ++bp; 442 ++cnt; 443 } 444 return (cnt); 445 } 446 447 /* 448 * Build proc info array by reading in proc list from a crash dump. 449 * Return number of procs read. maxcnt is the max we will read. 450 */ 451 static int 452 kvm_deadprocs(kd, what, arg, a_allproc, a_zombproc, maxcnt) 453 kvm_t *kd; 454 int what, arg; 455 u_long a_allproc; 456 u_long a_zombproc; 457 int maxcnt; 458 { 459 register struct kinfo_proc *bp = kd->procbase; 460 register int acnt, zcnt; 461 struct proc *p; 462 463 if (KREAD(kd, a_allproc, &p)) { 464 _kvm_err(kd, kd->program, "cannot read allproc"); 465 return (-1); 466 } 467 acnt = kvm_proclist(kd, what, arg, p, bp, maxcnt); 468 if (acnt < 0) 469 return (acnt); 470 471 if (KREAD(kd, a_zombproc, &p)) { 472 _kvm_err(kd, kd->program, "cannot read zombproc"); 473 return (-1); 474 } 475 zcnt = kvm_proclist(kd, what, arg, p, bp + acnt, maxcnt - acnt); 476 if (zcnt < 0) 477 zcnt = 0; 478 479 return (acnt + zcnt); 480 } 481 482 struct kinfo_proc * 483 kvm_getprocs(kd, op, arg, cnt) 484 kvm_t *kd; 485 int op, arg; 486 int *cnt; 487 { 488 size_t size; 489 int mib[4], st, nprocs; 490 491 if (kd->procbase != 0) { 492 free((void *)kd->procbase); 493 /* 494 * Clear this pointer in case this call fails. Otherwise, 495 * kvm_close() will free it again. 496 */ 497 kd->procbase = 0; 498 } 499 if (ISALIVE(kd)) { 500 size = 0; 501 mib[0] = CTL_KERN; 502 mib[1] = KERN_PROC; 503 mib[2] = op; 504 mib[3] = arg; 505 st = sysctl(mib, 4, NULL, &size, NULL, 0); 506 if (st == -1) { 507 _kvm_syserr(kd, kd->program, "kvm_getprocs"); 508 return (0); 509 } 510 kd->procbase = (struct kinfo_proc *)_kvm_malloc(kd, size); 511 if (kd->procbase == 0) 512 return (0); 513 st = sysctl(mib, 4, kd->procbase, &size, NULL, 0); 514 if (st == -1) { 515 _kvm_syserr(kd, kd->program, "kvm_getprocs"); 516 return (0); 517 } 518 if (size % sizeof(struct kinfo_proc) != 0) { 519 _kvm_err(kd, kd->program, 520 "proc size mismatch (%d total, %d chunks)", 521 size, sizeof(struct kinfo_proc)); 522 return (0); 523 } 524 nprocs = size / sizeof(struct kinfo_proc); 525 } else { 526 struct nlist nl[4], *p; 527 528 nl[0].n_name = "_nprocs"; 529 nl[1].n_name = "_allproc"; 530 nl[2].n_name = "_zombproc"; 531 nl[3].n_name = 0; 532 533 if (kvm_nlist(kd, nl) != 0) { 534 for (p = nl; p->n_type != 0; ++p) 535 ; 536 _kvm_err(kd, kd->program, 537 "%s: no such symbol", p->n_name); 538 return (0); 539 } 540 if (KREAD(kd, nl[0].n_value, &nprocs)) { 541 _kvm_err(kd, kd->program, "can't read nprocs"); 542 return (0); 543 } 544 size = nprocs * sizeof(struct kinfo_proc); 545 kd->procbase = (struct kinfo_proc *)_kvm_malloc(kd, size); 546 if (kd->procbase == 0) 547 return (0); 548 549 nprocs = kvm_deadprocs(kd, op, arg, nl[1].n_value, 550 nl[2].n_value, nprocs); 551 #ifdef notdef 552 size = nprocs * sizeof(struct kinfo_proc); 553 (void)realloc(kd->procbase, size); 554 #endif 555 } 556 *cnt = nprocs; 557 return (kd->procbase); 558 } 559 560 void 561 _kvm_freeprocs(kd) 562 kvm_t *kd; 563 { 564 if (kd->procbase) { 565 free(kd->procbase); 566 kd->procbase = 0; 567 } 568 } 569 570 void * 571 _kvm_realloc(kd, p, n) 572 kvm_t *kd; 573 void *p; 574 size_t n; 575 { 576 void *np = (void *)realloc(p, n); 577 578 if (np == 0) 579 _kvm_err(kd, kd->program, "out of memory"); 580 return (np); 581 } 582 583 #ifndef MAX 584 #define MAX(a, b) ((a) > (b) ? (a) : (b)) 585 #endif 586 587 /* 588 * Read in an argument vector from the user address space of process p. 589 * addr if the user-space base address of narg null-terminated contiguous 590 * strings. This is used to read in both the command arguments and 591 * environment strings. Read at most maxcnt characters of strings. 592 */ 593 static char ** 594 kvm_argv(kd, p, addr, narg, maxcnt) 595 kvm_t *kd; 596 const struct proc *p; 597 register u_long addr; 598 register int narg; 599 register int maxcnt; 600 { 601 register char *np, *cp, *ep, *ap; 602 register u_long oaddr = -1; 603 register int len, cc; 604 register char **argv; 605 606 /* 607 * Check that there aren't an unreasonable number of agruments, 608 * and that the address is in user space. 609 */ 610 if (narg > ARG_MAX || addr < kd->min_uva || addr >= kd->max_uva) 611 return (0); 612 613 if (kd->argv == 0) { 614 /* 615 * Try to avoid reallocs. 616 */ 617 kd->argc = MAX(narg + 1, 32); 618 kd->argv = (char **)_kvm_malloc(kd, kd->argc * 619 sizeof(*kd->argv)); 620 if (kd->argv == 0) 621 return (0); 622 } else if (narg + 1 > kd->argc) { 623 kd->argc = MAX(2 * kd->argc, narg + 1); 624 kd->argv = (char **)_kvm_realloc(kd, kd->argv, kd->argc * 625 sizeof(*kd->argv)); 626 if (kd->argv == 0) 627 return (0); 628 } 629 if (kd->argspc == 0) { 630 kd->argspc = (char *)_kvm_malloc(kd, kd->nbpg); 631 if (kd->argspc == 0) 632 return (0); 633 kd->arglen = kd->nbpg; 634 } 635 if (kd->argbuf == 0) { 636 kd->argbuf = (char *)_kvm_malloc(kd, kd->nbpg); 637 if (kd->argbuf == 0) 638 return (0); 639 } 640 cc = sizeof(char *) * narg; 641 if (kvm_uread(kd, p, addr, (char *)kd->argv, cc) != cc) 642 return (0); 643 ap = np = kd->argspc; 644 argv = kd->argv; 645 len = 0; 646 /* 647 * Loop over pages, filling in the argument vector. 648 */ 649 while (argv < kd->argv + narg && *argv != 0) { 650 addr = (u_long)*argv & ~(kd->nbpg - 1); 651 if (addr != oaddr) { 652 if (kvm_uread(kd, p, addr, kd->argbuf, kd->nbpg) != 653 kd->nbpg) 654 return (0); 655 oaddr = addr; 656 } 657 addr = (u_long)*argv & (kd->nbpg - 1); 658 cp = kd->argbuf + addr; 659 cc = kd->nbpg - addr; 660 if (maxcnt > 0 && cc > maxcnt - len) 661 cc = maxcnt - len;; 662 ep = memchr(cp, '\0', cc); 663 if (ep != 0) 664 cc = ep - cp + 1; 665 if (len + cc > kd->arglen) { 666 register int off; 667 register char **pp; 668 register char *op = kd->argspc; 669 670 kd->arglen *= 2; 671 kd->argspc = (char *)_kvm_realloc(kd, kd->argspc, 672 kd->arglen); 673 if (kd->argspc == 0) 674 return (0); 675 /* 676 * Adjust argv pointers in case realloc moved 677 * the string space. 678 */ 679 off = kd->argspc - op; 680 for (pp = kd->argv; pp < argv; pp++) 681 *pp += off; 682 ap += off; 683 np += off; 684 } 685 memcpy(np, cp, cc); 686 np += cc; 687 len += cc; 688 if (ep != 0) { 689 *argv++ = ap; 690 ap = np; 691 } else 692 *argv += cc; 693 if (maxcnt > 0 && len >= maxcnt) { 694 /* 695 * We're stopping prematurely. Terminate the 696 * current string. 697 */ 698 if (ep == 0) { 699 *np = '\0'; 700 *argv++ = ap; 701 } 702 break; 703 } 704 } 705 /* Make sure argv is terminated. */ 706 *argv = 0; 707 return (kd->argv); 708 } 709 710 static void 711 ps_str_a(p, addr, n) 712 struct ps_strings *p; 713 u_long *addr; 714 int *n; 715 { 716 *addr = (u_long)p->ps_argvstr; 717 *n = p->ps_nargvstr; 718 } 719 720 static void 721 ps_str_e(p, addr, n) 722 struct ps_strings *p; 723 u_long *addr; 724 int *n; 725 { 726 *addr = (u_long)p->ps_envstr; 727 *n = p->ps_nenvstr; 728 } 729 730 /* 731 * Determine if the proc indicated by p is still active. 732 * This test is not 100% foolproof in theory, but chances of 733 * being wrong are very low. 734 */ 735 static int 736 proc_verify(kd, kernp, p) 737 kvm_t *kd; 738 u_long kernp; 739 const struct proc *p; 740 { 741 struct proc kernproc; 742 743 /* 744 * Just read in the whole proc. It's not that big relative 745 * to the cost of the read system call. 746 */ 747 if (kvm_read(kd, kernp, (char *)&kernproc, sizeof(kernproc)) != 748 sizeof(kernproc)) 749 return (0); 750 return (p->p_pid == kernproc.p_pid && 751 (kernproc.p_stat != SZOMB || p->p_stat == SZOMB)); 752 } 753 754 static char ** 755 kvm_doargv(kd, kp, nchr, info) 756 kvm_t *kd; 757 const struct kinfo_proc *kp; 758 int nchr; 759 void (*info)(struct ps_strings *, u_long *, int *); 760 { 761 register const struct proc *p = &kp->kp_proc; 762 register char **ap; 763 u_long addr; 764 int cnt; 765 struct ps_strings arginfo; 766 767 /* 768 * Pointers are stored at the top of the user stack. 769 */ 770 if (p->p_stat == SZOMB) 771 return (0); 772 cnt = kvm_uread(kd, p, kd->usrstack - sizeof(arginfo), 773 (char *)&arginfo, sizeof(arginfo)); 774 if (cnt != sizeof(arginfo)) 775 return (0); 776 777 (*info)(&arginfo, &addr, &cnt); 778 if (cnt == 0) 779 return (0); 780 ap = kvm_argv(kd, p, addr, cnt, nchr); 781 /* 782 * For live kernels, make sure this process didn't go away. 783 */ 784 if (ap != 0 && ISALIVE(kd) && 785 !proc_verify(kd, (u_long)kp->kp_eproc.e_paddr, p)) 786 ap = 0; 787 return (ap); 788 } 789 790 /* 791 * Get the command args. This code is now machine independent. 792 */ 793 char ** 794 kvm_getargv(kd, kp, nchr) 795 kvm_t *kd; 796 const struct kinfo_proc *kp; 797 int nchr; 798 { 799 return (kvm_doargv(kd, kp, nchr, ps_str_a)); 800 } 801 802 char ** 803 kvm_getenvv(kd, kp, nchr) 804 kvm_t *kd; 805 const struct kinfo_proc *kp; 806 int nchr; 807 { 808 return (kvm_doargv(kd, kp, nchr, ps_str_e)); 809 } 810 811 /* 812 * Read from user space. The user context is given by p. 813 */ 814 ssize_t 815 kvm_uread(kd, p, uva, buf, len) 816 kvm_t *kd; 817 register const struct proc *p; 818 register u_long uva; 819 register char *buf; 820 register size_t len; 821 { 822 register char *cp; 823 824 cp = buf; 825 while (len > 0) { 826 register int cc; 827 register char *dp; 828 u_long cnt; 829 830 dp = _kvm_uread(kd, p, uva, &cnt); 831 if (dp == 0) { 832 _kvm_err(kd, 0, "invalid address (%x)", uva); 833 return (0); 834 } 835 cc = MIN(cnt, len); 836 bcopy(dp, cp, cc); 837 838 cp += cc; 839 uva += cc; 840 len -= cc; 841 } 842 return (ssize_t)(cp - buf); 843 } 844
Indexes created Tue Sep 23 02:09:52 GMT 2025