kvm_proc.c revision 1.22
1 /* $NetBSD: kvm_proc.c,v 1.22 1998/02/11 12:00:37 mrg 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 1.22 1998/02/11 12:00:37 mrg 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 char *_kvm_uread __P((kvm_t *, const struct proc *, u_long, u_long *)); 86 int _kvm_coreinit __P((kvm_t *)); 87 int _kvm_readfromcore __P((kvm_t *, u_long, u_long)); 88 int _kvm_readfrompager __P((kvm_t *, struct vm_object *, u_long)); 89 ssize_t kvm_uread __P((kvm_t *, const struct proc *, u_long, char *, 90 size_t)); 91 92 static char **kvm_argv __P((kvm_t *, const struct proc *, u_long, int, 93 int)); 94 static int kvm_deadprocs __P((kvm_t *, int, int, u_long, u_long, int)); 95 static char **kvm_doargv __P((kvm_t *, const struct kinfo_proc *, int, 96 void (*)(struct ps_strings *, u_long *, int *))); 97 static int kvm_proclist __P((kvm_t *, int, int, struct proc *, 98 struct kinfo_proc *, int)); 99 static int proc_verify __P((kvm_t *, u_long, const struct proc *)); 100 static void ps_str_a __P((struct ps_strings *, u_long *, int *)); 101 static void ps_str_e __P((struct ps_strings *, u_long *, int *)); 102 103 char * 104 _kvm_uread(kd, p, va, cnt) 105 kvm_t *kd; 106 const struct proc *p; 107 u_long va; 108 u_long *cnt; 109 { 110 u_long addr, head; 111 u_long offset; 112 struct vm_map_entry vme; 113 struct vm_object vmo; 114 int rv; 115 116 if (kd->swapspc == 0) { 117 kd->swapspc = (char *)_kvm_malloc(kd, kd->nbpg); 118 if (kd->swapspc == 0) 119 return (0); 120 } 121 122 /* 123 * Look through the address map for the memory object 124 * that corresponds to the given virtual address. 125 * The header just has the entire valid range. 126 */ 127 head = (u_long)&p->p_vmspace->vm_map.header; 128 addr = head; 129 while (1) { 130 if (KREAD(kd, addr, &vme)) 131 return (0); 132 133 if (va >= vme.start && va < vme.end && 134 vme.object.vm_object != 0) 135 break; 136 137 addr = (u_long)vme.next; 138 if (addr == head) 139 return (0); 140 } 141 142 /* 143 * We found the right object -- follow shadow links. 144 */ 145 offset = va - vme.start + vme.offset; 146 addr = (u_long)vme.object.vm_object; 147 148 while (1) { 149 /* Try reading the page from core first. */ 150 if ((rv = _kvm_readfromcore(kd, addr, offset))) 151 break; 152 153 if (KREAD(kd, addr, &vmo)) 154 return (0); 155 156 /* If there is a pager here, see if it has the page. */ 157 if (vmo.pager != 0 && 158 (rv = _kvm_readfrompager(kd, &vmo, offset))) 159 break; 160 161 /* Move down the shadow chain. */ 162 addr = (u_long)vmo.shadow; 163 if (addr == 0) 164 return (0); 165 offset += vmo.shadow_offset; 166 } 167 168 if (rv == -1) 169 return (0); 170 171 /* Found the page. */ 172 offset %= kd->nbpg; 173 *cnt = kd->nbpg - offset; 174 return (&kd->swapspc[offset]); 175 } 176 177 #define vm_page_hash(kd, object, offset) \ 178 (((u_long)object + (u_long)(offset / kd->nbpg)) & kd->vm_page_hash_mask) 179 180 int 181 _kvm_coreinit(kd) 182 kvm_t *kd; 183 { 184 struct nlist nlist[3]; 185 186 nlist[0].n_name = "_vm_page_buckets"; 187 nlist[1].n_name = "_vm_page_hash_mask"; 188 nlist[2].n_name = 0; 189 if (kvm_nlist(kd, nlist) != 0) 190 return (-1); 191 192 if (KREAD(kd, nlist[0].n_value, &kd->vm_page_buckets) || 193 KREAD(kd, nlist[1].n_value, &kd->vm_page_hash_mask)) 194 return (-1); 195 196 return (0); 197 } 198 199 int 200 _kvm_readfromcore(kd, object, offset) 201 kvm_t *kd; 202 u_long object, offset; 203 { 204 u_long addr; 205 struct pglist bucket; 206 struct vm_page mem; 207 off_t seekpoint; 208 209 if (kd->vm_page_buckets == 0 && 210 _kvm_coreinit(kd)) 211 return (-1); 212 213 addr = (u_long)&kd->vm_page_buckets[vm_page_hash(kd, object, offset)]; 214 if (KREAD(kd, addr, &bucket)) 215 return (-1); 216 217 addr = (u_long)bucket.tqh_first; 218 offset &= ~(kd->nbpg -1); 219 while (1) { 220 if (addr == 0) 221 return (0); 222 223 if (KREAD(kd, addr, &mem)) 224 return (-1); 225 226 #if defined(UVM) 227 if ((u_long)mem.uobject == object && 228 (u_long)mem.offset == offset) 229 #else 230 if ((u_long)mem.object == object && 231 (u_long)mem.offset == offset) 232 #endif 233 break; 234 235 addr = (u_long)mem.hashq.tqe_next; 236 } 237 238 seekpoint = mem.phys_addr; 239 240 if (lseek(kd->pmfd, seekpoint, 0) == -1) 241 return (-1); 242 if (read(kd->pmfd, kd->swapspc, kd->nbpg) != kd->nbpg) 243 return (-1); 244 245 return (1); 246 } 247 248 int 249 _kvm_readfrompager(kd, vmop, offset) 250 kvm_t *kd; 251 struct vm_object *vmop; 252 u_long offset; 253 { 254 u_long addr; 255 struct pager_struct pager; 256 struct swpager swap; 257 int ix; 258 struct swblock swb; 259 off_t seekpoint; 260 261 /* Read in the pager info and make sure it's a swap device. */ 262 addr = (u_long)vmop->pager; 263 if (KREAD(kd, addr, &pager) || pager.pg_type != PG_SWAP) 264 return (-1); 265 266 /* Read in the swap_pager private data. */ 267 addr = (u_long)pager.pg_data; 268 if (KREAD(kd, addr, &swap)) 269 return (-1); 270 271 /* 272 * Calculate the paging offset, and make sure it's within the 273 * bounds of the pager. 274 */ 275 offset += vmop->paging_offset; 276 ix = offset / dbtob(swap.sw_bsize); 277 #if 0 278 if (swap.sw_blocks == 0 || ix >= swap.sw_nblocks) 279 return (-1); 280 #else 281 if (swap.sw_blocks == 0 || ix >= swap.sw_nblocks) { 282 int i; 283 printf("BUG BUG BUG BUG:\n"); 284 printf("object %p offset %lx pgoffset %lx ", 285 vmop, offset - vmop->paging_offset, 286 (u_long)vmop->paging_offset); 287 printf("pager %p swpager %p\n", 288 vmop->pager, pager.pg_data); 289 printf("osize %lx bsize %x blocks %p nblocks %x\n", 290 (u_long)swap.sw_osize, swap.sw_bsize, swap.sw_blocks, 291 swap.sw_nblocks); 292 for (i = 0; i < swap.sw_nblocks; i++) { 293 addr = (u_long)&swap.sw_blocks[i]; 294 if (KREAD(kd, addr, &swb)) 295 return (0); 296 printf("sw_blocks[%d]: block %x mask %x\n", i, 297 swb.swb_block, swb.swb_mask); 298 } 299 return (-1); 300 } 301 #endif 302 303 /* Read in the swap records. */ 304 addr = (u_long)&swap.sw_blocks[ix]; 305 if (KREAD(kd, addr, &swb)) 306 return (-1); 307 308 /* Calculate offset within pager. */ 309 offset %= dbtob(swap.sw_bsize); 310 311 /* Check that the page is actually present. */ 312 if ((swb.swb_mask & (1 << (offset / kd->nbpg))) == 0) 313 return (0); 314 315 if (!ISALIVE(kd)) 316 return (-1); 317 318 /* Calculate the physical address and read the page. */ 319 seekpoint = dbtob(swb.swb_block) + (offset & ~(kd->nbpg -1)); 320 321 if (lseek(kd->swfd, seekpoint, 0) == -1) 322 return (-1); 323 if (read(kd->swfd, kd->swapspc, kd->nbpg) != kd->nbpg) 324 return (-1); 325 326 return (1); 327 } 328 329 /* 330 * Read proc's from memory file into buffer bp, which has space to hold 331 * at most maxcnt procs. 332 */ 333 static int 334 kvm_proclist(kd, what, arg, p, bp, maxcnt) 335 kvm_t *kd; 336 int what, arg; 337 struct proc *p; 338 struct kinfo_proc *bp; 339 int maxcnt; 340 { 341 int cnt = 0; 342 struct eproc eproc; 343 struct pgrp pgrp; 344 struct session sess; 345 struct tty tty; 346 struct proc proc; 347 348 for (; cnt < maxcnt && p != NULL; p = proc.p_list.le_next) { 349 if (KREAD(kd, (u_long)p, &proc)) { 350 _kvm_err(kd, kd->program, "can't read proc at %x", p); 351 return (-1); 352 } 353 if (KREAD(kd, (u_long)proc.p_cred, &eproc.e_pcred) == 0) 354 (void)KREAD(kd, (u_long)eproc.e_pcred.pc_ucred, 355 &eproc.e_ucred); 356 357 switch(what) { 358 359 case KERN_PROC_PID: 360 if (proc.p_pid != (pid_t)arg) 361 continue; 362 break; 363 364 case KERN_PROC_UID: 365 if (eproc.e_ucred.cr_uid != (uid_t)arg) 366 continue; 367 break; 368 369 case KERN_PROC_RUID: 370 if (eproc.e_pcred.p_ruid != (uid_t)arg) 371 continue; 372 break; 373 } 374 /* 375 * We're going to add another proc to the set. If this 376 * will overflow the buffer, assume the reason is because 377 * nprocs (or the proc list) is corrupt and declare an error. 378 */ 379 if (cnt >= maxcnt) { 380 _kvm_err(kd, kd->program, "nprocs corrupt"); 381 return (-1); 382 } 383 /* 384 * gather eproc 385 */ 386 eproc.e_paddr = p; 387 if (KREAD(kd, (u_long)proc.p_pgrp, &pgrp)) { 388 _kvm_err(kd, kd->program, "can't read pgrp at %x", 389 proc.p_pgrp); 390 return (-1); 391 } 392 eproc.e_sess = pgrp.pg_session; 393 eproc.e_pgid = pgrp.pg_id; 394 eproc.e_jobc = pgrp.pg_jobc; 395 if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) { 396 _kvm_err(kd, kd->program, "can't read session at %x", 397 pgrp.pg_session); 398 return (-1); 399 } 400 if ((proc.p_flag & P_CONTROLT) && sess.s_ttyp != NULL) { 401 if (KREAD(kd, (u_long)sess.s_ttyp, &tty)) { 402 _kvm_err(kd, kd->program, 403 "can't read tty at %x", sess.s_ttyp); 404 return (-1); 405 } 406 eproc.e_tdev = tty.t_dev; 407 eproc.e_tsess = tty.t_session; 408 if (tty.t_pgrp != NULL) { 409 if (KREAD(kd, (u_long)tty.t_pgrp, &pgrp)) { 410 _kvm_err(kd, kd->program, 411 "can't read tpgrp at &x", 412 tty.t_pgrp); 413 return (-1); 414 } 415 eproc.e_tpgid = pgrp.pg_id; 416 } else 417 eproc.e_tpgid = -1; 418 } else 419 eproc.e_tdev = NODEV; 420 eproc.e_flag = sess.s_ttyvp ? EPROC_CTTY : 0; 421 if (sess.s_leader == p) 422 eproc.e_flag |= EPROC_SLEADER; 423 if (proc.p_wmesg) 424 (void)kvm_read(kd, (u_long)proc.p_wmesg, 425 eproc.e_wmesg, WMESGLEN); 426 427 (void)kvm_read(kd, (u_long)proc.p_vmspace, 428 (char *)&eproc.e_vm, sizeof(eproc.e_vm)); 429 430 eproc.e_xsize = eproc.e_xrssize = 0; 431 eproc.e_xccount = eproc.e_xswrss = 0; 432 433 switch (what) { 434 435 case KERN_PROC_PGRP: 436 if (eproc.e_pgid != (pid_t)arg) 437 continue; 438 break; 439 440 case KERN_PROC_TTY: 441 if ((proc.p_flag & P_CONTROLT) == 0 || 442 eproc.e_tdev != (dev_t)arg) 443 continue; 444 break; 445 } 446 bcopy(&proc, &bp->kp_proc, sizeof(proc)); 447 bcopy(&eproc, &bp->kp_eproc, sizeof(eproc)); 448 ++bp; 449 ++cnt; 450 } 451 return (cnt); 452 } 453 454 /* 455 * Build proc info array by reading in proc list from a crash dump. 456 * Return number of procs read. maxcnt is the max we will read. 457 */ 458 static int 459 kvm_deadprocs(kd, what, arg, a_allproc, a_zombproc, maxcnt) 460 kvm_t *kd; 461 int what, arg; 462 u_long a_allproc; 463 u_long a_zombproc; 464 int maxcnt; 465 { 466 struct kinfo_proc *bp = kd->procbase; 467 int acnt, zcnt; 468 struct proc *p; 469 470 if (KREAD(kd, a_allproc, &p)) { 471 _kvm_err(kd, kd->program, "cannot read allproc"); 472 return (-1); 473 } 474 acnt = kvm_proclist(kd, what, arg, p, bp, maxcnt); 475 if (acnt < 0) 476 return (acnt); 477 478 if (KREAD(kd, a_zombproc, &p)) { 479 _kvm_err(kd, kd->program, "cannot read zombproc"); 480 return (-1); 481 } 482 zcnt = kvm_proclist(kd, what, arg, p, bp + acnt, maxcnt - acnt); 483 if (zcnt < 0) 484 zcnt = 0; 485 486 return (acnt + zcnt); 487 } 488 489 struct kinfo_proc * 490 kvm_getprocs(kd, op, arg, cnt) 491 kvm_t *kd; 492 int op, arg; 493 int *cnt; 494 { 495 size_t size; 496 int mib[4], st, nprocs; 497 498 if (kd->procbase != 0) { 499 free((void *)kd->procbase); 500 /* 501 * Clear this pointer in case this call fails. Otherwise, 502 * kvm_close() will free it again. 503 */ 504 kd->procbase = 0; 505 } 506 if (ISALIVE(kd)) { 507 size = 0; 508 mib[0] = CTL_KERN; 509 mib[1] = KERN_PROC; 510 mib[2] = op; 511 mib[3] = arg; 512 st = sysctl(mib, 4, NULL, &size, NULL, 0); 513 if (st == -1) { 514 _kvm_syserr(kd, kd->program, "kvm_getprocs"); 515 return (0); 516 } 517 kd->procbase = (struct kinfo_proc *)_kvm_malloc(kd, size); 518 if (kd->procbase == 0) 519 return (0); 520 st = sysctl(mib, 4, kd->procbase, &size, NULL, 0); 521 if (st == -1) { 522 _kvm_syserr(kd, kd->program, "kvm_getprocs"); 523 return (0); 524 } 525 if (size % sizeof(struct kinfo_proc) != 0) { 526 _kvm_err(kd, kd->program, 527 "proc size mismatch (%d total, %d chunks)", 528 size, sizeof(struct kinfo_proc)); 529 return (0); 530 } 531 nprocs = size / sizeof(struct kinfo_proc); 532 } else { 533 struct nlist nl[4], *p; 534 535 nl[0].n_name = "_nprocs"; 536 nl[1].n_name = "_allproc"; 537 nl[2].n_name = "_zombproc"; 538 nl[3].n_name = 0; 539 540 if (kvm_nlist(kd, nl) != 0) { 541 for (p = nl; p->n_type != 0; ++p) 542 ; 543 _kvm_err(kd, kd->program, 544 "%s: no such symbol", p->n_name); 545 return (0); 546 } 547 if (KREAD(kd, nl[0].n_value, &nprocs)) { 548 _kvm_err(kd, kd->program, "can't read nprocs"); 549 return (0); 550 } 551 size = nprocs * sizeof(struct kinfo_proc); 552 kd->procbase = (struct kinfo_proc *)_kvm_malloc(kd, size); 553 if (kd->procbase == 0) 554 return (0); 555 556 nprocs = kvm_deadprocs(kd, op, arg, nl[1].n_value, 557 nl[2].n_value, nprocs); 558 #ifdef notdef 559 size = nprocs * sizeof(struct kinfo_proc); 560 (void)realloc(kd->procbase, size); 561 #endif 562 } 563 *cnt = nprocs; 564 return (kd->procbase); 565 } 566 567 void 568 _kvm_freeprocs(kd) 569 kvm_t *kd; 570 { 571 if (kd->procbase) { 572 free(kd->procbase); 573 kd->procbase = 0; 574 } 575 } 576 577 void * 578 _kvm_realloc(kd, p, n) 579 kvm_t *kd; 580 void *p; 581 size_t n; 582 { 583 void *np = (void *)realloc(p, n); 584 585 if (np == 0) 586 _kvm_err(kd, kd->program, "out of memory"); 587 return (np); 588 } 589 590 #ifndef MAX 591 #define MAX(a, b) ((a) > (b) ? (a) : (b)) 592 #endif 593 594 /* 595 * Read in an argument vector from the user address space of process p. 596 * addr if the user-space base address of narg null-terminated contiguous 597 * strings. This is used to read in both the command arguments and 598 * environment strings. Read at most maxcnt characters of strings. 599 */ 600 static char ** 601 kvm_argv(kd, p, addr, narg, maxcnt) 602 kvm_t *kd; 603 const struct proc *p; 604 u_long addr; 605 int narg; 606 int maxcnt; 607 { 608 char *np, *cp, *ep, *ap; 609 u_long oaddr = -1; 610 int len, cc; 611 char **argv; 612 613 /* 614 * Check that there aren't an unreasonable number of agruments, 615 * and that the address is in user space. 616 */ 617 if (narg > ARG_MAX || addr < kd->min_uva || addr >= kd->max_uva) 618 return (0); 619 620 if (kd->argv == 0) { 621 /* 622 * Try to avoid reallocs. 623 */ 624 kd->argc = MAX(narg + 1, 32); 625 kd->argv = (char **)_kvm_malloc(kd, kd->argc * 626 sizeof(*kd->argv)); 627 if (kd->argv == 0) 628 return (0); 629 } else if (narg + 1 > kd->argc) { 630 kd->argc = MAX(2 * kd->argc, narg + 1); 631 kd->argv = (char **)_kvm_realloc(kd, kd->argv, kd->argc * 632 sizeof(*kd->argv)); 633 if (kd->argv == 0) 634 return (0); 635 } 636 if (kd->argspc == 0) { 637 kd->argspc = (char *)_kvm_malloc(kd, kd->nbpg); 638 if (kd->argspc == 0) 639 return (0); 640 kd->arglen = kd->nbpg; 641 } 642 if (kd->argbuf == 0) { 643 kd->argbuf = (char *)_kvm_malloc(kd, kd->nbpg); 644 if (kd->argbuf == 0) 645 return (0); 646 } 647 cc = sizeof(char *) * narg; 648 if (kvm_uread(kd, p, addr, (char *)kd->argv, cc) != cc) 649 return (0); 650 ap = np = kd->argspc; 651 argv = kd->argv; 652 len = 0; 653 /* 654 * Loop over pages, filling in the argument vector. 655 */ 656 while (argv < kd->argv + narg && *argv != 0) { 657 addr = (u_long)*argv & ~(kd->nbpg - 1); 658 if (addr != oaddr) { 659 if (kvm_uread(kd, p, addr, kd->argbuf, kd->nbpg) != 660 kd->nbpg) 661 return (0); 662 oaddr = addr; 663 } 664 addr = (u_long)*argv & (kd->nbpg - 1); 665 cp = kd->argbuf + addr; 666 cc = kd->nbpg - addr; 667 if (maxcnt > 0 && cc > maxcnt - len) 668 cc = maxcnt - len;; 669 ep = memchr(cp, '\0', cc); 670 if (ep != 0) 671 cc = ep - cp + 1; 672 if (len + cc > kd->arglen) { 673 int off; 674 char **pp; 675 char *op = kd->argspc; 676 677 kd->arglen *= 2; 678 kd->argspc = (char *)_kvm_realloc(kd, kd->argspc, 679 kd->arglen); 680 if (kd->argspc == 0) 681 return (0); 682 /* 683 * Adjust argv pointers in case realloc moved 684 * the string space. 685 */ 686 off = kd->argspc - op; 687 for (pp = kd->argv; pp < argv; pp++) 688 *pp += off; 689 ap += off; 690 np += off; 691 } 692 memcpy(np, cp, cc); 693 np += cc; 694 len += cc; 695 if (ep != 0) { 696 *argv++ = ap; 697 ap = np; 698 } else 699 *argv += cc; 700 if (maxcnt > 0 && len >= maxcnt) { 701 /* 702 * We're stopping prematurely. Terminate the 703 * current string. 704 */ 705 if (ep == 0) { 706 *np = '\0'; 707 *argv++ = ap; 708 } 709 break; 710 } 711 } 712 /* Make sure argv is terminated. */ 713 *argv = 0; 714 return (kd->argv); 715 } 716 717 static void 718 ps_str_a(p, addr, n) 719 struct ps_strings *p; 720 u_long *addr; 721 int *n; 722 { 723 *addr = (u_long)p->ps_argvstr; 724 *n = p->ps_nargvstr; 725 } 726 727 static void 728 ps_str_e(p, addr, n) 729 struct ps_strings *p; 730 u_long *addr; 731 int *n; 732 { 733 *addr = (u_long)p->ps_envstr; 734 *n = p->ps_nenvstr; 735 } 736 737 /* 738 * Determine if the proc indicated by p is still active. 739 * This test is not 100% foolproof in theory, but chances of 740 * being wrong are very low. 741 */ 742 static int 743 proc_verify(kd, kernp, p) 744 kvm_t *kd; 745 u_long kernp; 746 const struct proc *p; 747 { 748 struct proc kernproc; 749 750 /* 751 * Just read in the whole proc. It's not that big relative 752 * to the cost of the read system call. 753 */ 754 if (kvm_read(kd, kernp, (char *)&kernproc, sizeof(kernproc)) != 755 sizeof(kernproc)) 756 return (0); 757 return (p->p_pid == kernproc.p_pid && 758 (kernproc.p_stat != SZOMB || p->p_stat == SZOMB)); 759 } 760 761 static char ** 762 kvm_doargv(kd, kp, nchr, info) 763 kvm_t *kd; 764 const struct kinfo_proc *kp; 765 int nchr; 766 void (*info)(struct ps_strings *, u_long *, int *); 767 { 768 const struct proc *p = &kp->kp_proc; 769 char **ap; 770 u_long addr; 771 int cnt; 772 struct ps_strings arginfo; 773 774 /* 775 * Pointers are stored at the top of the user stack. 776 */ 777 if (p->p_stat == SZOMB) 778 return (0); 779 cnt = kvm_uread(kd, p, kd->usrstack - sizeof(arginfo), 780 (char *)&arginfo, sizeof(arginfo)); 781 if (cnt != sizeof(arginfo)) 782 return (0); 783 784 (*info)(&arginfo, &addr, &cnt); 785 if (cnt == 0) 786 return (0); 787 ap = kvm_argv(kd, p, addr, cnt, nchr); 788 /* 789 * For live kernels, make sure this process didn't go away. 790 */ 791 if (ap != 0 && ISALIVE(kd) && 792 !proc_verify(kd, (u_long)kp->kp_eproc.e_paddr, p)) 793 ap = 0; 794 return (ap); 795 } 796 797 /* 798 * Get the command args. This code is now machine independent. 799 */ 800 char ** 801 kvm_getargv(kd, kp, nchr) 802 kvm_t *kd; 803 const struct kinfo_proc *kp; 804 int nchr; 805 { 806 return (kvm_doargv(kd, kp, nchr, ps_str_a)); 807 } 808 809 char ** 810 kvm_getenvv(kd, kp, nchr) 811 kvm_t *kd; 812 const struct kinfo_proc *kp; 813 int nchr; 814 { 815 return (kvm_doargv(kd, kp, nchr, ps_str_e)); 816 } 817 818 /* 819 * Read from user space. The user context is given by p. 820 */ 821 ssize_t 822 kvm_uread(kd, p, uva, buf, len) 823 kvm_t *kd; 824 const struct proc *p; 825 u_long uva; 826 char *buf; 827 size_t len; 828 { 829 char *cp; 830 831 cp = buf; 832 while (len > 0) { 833 int cc; 834 char *dp; 835 u_long cnt; 836 837 dp = _kvm_uread(kd, p, uva, &cnt); 838 if (dp == 0) { 839 _kvm_err(kd, 0, "invalid address (%x)", uva); 840 return (0); 841 } 842 cc = MIN(cnt, len); 843 bcopy(dp, cp, cc); 844 845 cp += cc; 846 uva += cc; 847 len -= cc; 848 } 849 return (ssize_t)(cp - buf); 850 } 851
Indexes created Tue Sep 23 23:09:58 GMT 2025