1 /* $OpenBSD: kern_exec.c,v 1.27 1999/04/22 19:37:43 art Exp $ */ 2 /* $NetBSD: kern_exec.c,v 1.75 1996/02/09 18:59:28 christos Exp $ */ 3 4 /*- 5 * Copyright (C) 1993, 1994 Christopher G. Demetriou 6 * Copyright (C) 1992 Wolfgang Solfrank. 7 * Copyright (C) 1992 TooLs GmbH. 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by TooLs GmbH. 21 * 4. The name of TooLs GmbH may not be used to endorse or promote products 22 * derived from this software without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 27 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 29 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 30 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 31 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 32 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 33 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/filedesc.h> 39 #include <sys/kernel.h> 40 #include <sys/proc.h> 41 #include <sys/mount.h> 42 #include <sys/malloc.h> 43 #include <sys/namei.h> 44 #include <sys/vnode.h> 45 #include <sys/file.h> 46 #include <sys/acct.h> 47 #include <sys/exec.h> 48 #include <sys/ktrace.h> 49 #include <sys/resourcevar.h> 50 #include <sys/wait.h> 51 #include <sys/mman.h> 52 #include <sys/signalvar.h> 53 #include <sys/stat.h> 54 #ifdef SYSVSHM 55 #include <sys/shm.h> 56 #endif 57 58 #include <sys/syscallargs.h> 59 60 #include <vm/vm.h> 61 #include <vm/vm_kern.h> 62 63 #if defined(UVM) 64 #include <uvm/uvm_extern.h> 65 #endif 66 67 #include <machine/cpu.h> 68 #include <machine/reg.h> 69 70 /* 71 * check exec: 72 * given an "executable" described in the exec package's namei info, 73 * see what we can do with it. 74 * 75 * ON ENTRY: 76 * exec package with appropriate namei info 77 * proc pointer of exec'ing proc 78 * NO SELF-LOCKED VNODES 79 * 80 * ON EXIT: 81 * error: nothing held, etc. exec header still allocated. 82 * ok: filled exec package, one locked vnode. 83 * 84 * EXEC SWITCH ENTRY: 85 * Locked vnode to check, exec package, proc. 86 * 87 * EXEC SWITCH EXIT: 88 * ok: return 0, filled exec package, one locked vnode. 89 * error: destructive: 90 * everything deallocated execept exec header. 91 * non-descructive: 92 * error code, locked vnode, exec header unmodified 93 */ 94 int 95 check_exec(p, epp) 96 struct proc *p; 97 struct exec_package *epp; 98 { 99 int error, i; 100 struct vnode *vp; 101 struct nameidata *ndp; 102 size_t resid; 103 104 ndp = epp->ep_ndp; 105 ndp->ni_cnd.cn_nameiop = LOOKUP; 106 ndp->ni_cnd.cn_flags = FOLLOW | LOCKLEAF | SAVENAME; 107 /* first get the vnode */ 108 if ((error = namei(ndp)) != 0) 109 return (error); 110 epp->ep_vp = vp = ndp->ni_vp; 111 112 /* check for regular file */ 113 if (vp->v_type == VDIR) { 114 error = EISDIR; 115 goto bad1; 116 } 117 if (vp->v_type != VREG) { 118 error = EACCES; 119 goto bad1; 120 } 121 122 /* get attributes */ 123 if ((error = VOP_GETATTR(vp, epp->ep_vap, p->p_ucred, p)) != 0) 124 goto bad1; 125 126 /* Check mount point */ 127 if (vp->v_mount->mnt_flag & MNT_NOEXEC) { 128 error = EACCES; 129 goto bad1; 130 } 131 if ((vp->v_mount->mnt_flag & MNT_NOSUID) || 132 (p->p_flag & P_TRACED) || p->p_fd->fd_refcnt > 1) 133 epp->ep_vap->va_mode &= ~(VSUID | VSGID); 134 135 /* check access. for root we have to see if any exec bit on */ 136 if ((error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p)) != 0) 137 goto bad1; 138 if ((epp->ep_vap->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0) { 139 error = EACCES; 140 goto bad1; 141 } 142 143 /* try to open it */ 144 if ((error = VOP_OPEN(vp, FREAD, p->p_ucred, p)) != 0) 145 goto bad1; 146 147 /* now we have the file, get the exec header */ 148 error = vn_rdwr(UIO_READ, vp, epp->ep_hdr, epp->ep_hdrlen, 0, 149 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, p); 150 if (error) 151 goto bad2; 152 epp->ep_hdrvalid = epp->ep_hdrlen - resid; 153 154 /* 155 * set up the vmcmds for creation of the process 156 * address space 157 */ 158 error = ENOEXEC; 159 for (i = 0; i < nexecs && error != 0; i++) { 160 int newerror; 161 162 if (execsw[i].es_check == NULL) 163 continue; 164 165 newerror = (*execsw[i].es_check)(p, epp); 166 /* make sure the first "interesting" error code is saved. */ 167 if (!newerror || error == ENOEXEC) 168 error = newerror; 169 if (epp->ep_flags & EXEC_DESTR && error != 0) 170 return (error); 171 } 172 if (!error) { 173 /* check that entry point is sane */ 174 if (epp->ep_entry > VM_MAXUSER_ADDRESS) { 175 error = ENOEXEC; 176 } 177 178 /* check limits */ 179 if ((epp->ep_tsize > MAXTSIZ) || 180 (epp->ep_dsize > p->p_rlimit[RLIMIT_DATA].rlim_cur)) 181 error = ENOMEM; 182 183 if (!error) 184 return (0); 185 } 186 187 /* 188 * free any vmspace-creation commands, 189 * and release their references 190 */ 191 kill_vmcmds(&epp->ep_vmcmds); 192 193 bad2: 194 /* 195 * unlock and close the vnode, free the 196 * pathname buf, and punt. 197 */ 198 VOP_UNLOCK(vp, 0, p); 199 vn_close(vp, FREAD, p->p_ucred, p); 200 FREE(ndp->ni_cnd.cn_pnbuf, M_NAMEI); 201 return (error); 202 203 bad1: 204 /* 205 * free the namei pathname buffer, and put the vnode 206 * (which we don't yet have open). 207 */ 208 FREE(ndp->ni_cnd.cn_pnbuf, M_NAMEI); 209 vput(vp); 210 return (error); 211 } 212 213 /* 214 * exec system call 215 */ 216 /* ARGSUSED */ 217 int 218 sys_execve(p, v, retval) 219 register struct proc *p; 220 void *v; 221 register_t *retval; 222 { 223 register struct sys_execve_args /* { 224 syscallarg(char *) path; 225 syscallarg(char * *) argp; 226 syscallarg(char * *) envp; 227 } */ *uap = v; 228 int error, i; 229 struct exec_package pack; 230 struct nameidata nid; 231 struct vattr attr; 232 struct ucred *cred = p->p_ucred; 233 char *argp; 234 char * const *cpp, *dp, *sp; 235 long argc, envc; 236 size_t len; 237 char *stack; 238 struct ps_strings arginfo; 239 struct vmspace *vm = p->p_vmspace; 240 char **tmpfap; 241 int szsigcode; 242 extern struct emul emul_native; 243 244 /* 245 * figure out the maximum size of an exec header, if necessary. 246 * XXX should be able to keep LKM code from modifying exec switch 247 * when we're still using it, but... 248 */ 249 if (exec_maxhdrsz == 0) { 250 for (i = 0; i < nexecs; i++) 251 if (execsw[i].es_check != NULL 252 && execsw[i].es_hdrsz > exec_maxhdrsz) 253 exec_maxhdrsz = execsw[i].es_hdrsz; 254 } 255 256 /* init the namei data to point the file user's program name */ 257 NDINIT(&nid, LOOKUP, NOFOLLOW, UIO_USERSPACE, SCARG(uap, path), p); 258 259 /* 260 * initialize the fields of the exec package. 261 */ 262 pack.ep_name = (char *)SCARG(uap, path); 263 MALLOC(pack.ep_hdr, void *, exec_maxhdrsz, M_EXEC, M_WAITOK); 264 pack.ep_hdrlen = exec_maxhdrsz; 265 pack.ep_hdrvalid = 0; 266 pack.ep_ndp = &nid; 267 pack.ep_emul_arg = NULL; 268 pack.ep_vmcmds.evs_cnt = 0; 269 pack.ep_vmcmds.evs_used = 0; 270 pack.ep_vap = &attr; 271 pack.ep_emul = &emul_native; 272 pack.ep_flags = 0; 273 274 /* see if we can run it. */ 275 if ((error = check_exec(p, &pack)) != 0) { 276 goto freehdr; 277 } 278 279 /* XXX -- THE FOLLOWING SECTION NEEDS MAJOR CLEANUP */ 280 281 /* allocate an argument buffer */ 282 #if defined(UVM) 283 argp = (char *) uvm_km_valloc_wait(exec_map, NCARGS); 284 #else 285 argp = (char *)kmem_alloc_wait(exec_map, NCARGS); 286 #endif 287 #ifdef DIAGNOSTIC 288 if (argp == (vm_offset_t) 0) 289 panic("execve: argp == NULL"); 290 #endif 291 dp = argp; 292 argc = 0; 293 294 /* copy the fake args list, if there's one, freeing it as we go */ 295 if (pack.ep_flags & EXEC_HASARGL) { 296 tmpfap = pack.ep_fa; 297 while (*tmpfap != NULL) { 298 char *cp; 299 300 cp = *tmpfap; 301 while (*cp) 302 *dp++ = *cp++; 303 dp++; 304 305 FREE(*tmpfap, M_EXEC); 306 tmpfap++; argc++; 307 } 308 FREE(pack.ep_fa, M_EXEC); 309 pack.ep_flags &= ~EXEC_HASARGL; 310 } 311 312 /* Now get argv & environment */ 313 if (!(cpp = SCARG(uap, argp))) { 314 error = EINVAL; 315 goto bad; 316 } 317 318 if (pack.ep_flags & EXEC_SKIPARG) 319 cpp++; 320 321 while (1) { 322 len = argp + ARG_MAX - dp; 323 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0) 324 goto bad; 325 if (!sp) 326 break; 327 if ((error = copyinstr(sp, dp, len, &len)) != 0) { 328 if (error == ENAMETOOLONG) 329 error = E2BIG; 330 goto bad; 331 } 332 dp += len; 333 cpp++; 334 argc++; 335 } 336 337 envc = 0; 338 /* environment need not be there */ 339 if ((cpp = SCARG(uap, envp)) != NULL ) { 340 while (1) { 341 len = argp + ARG_MAX - dp; 342 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0) 343 goto bad; 344 if (!sp) 345 break; 346 if ((error = copyinstr(sp, dp, len, &len)) != 0) { 347 if (error == ENAMETOOLONG) 348 error = E2BIG; 349 goto bad; 350 } 351 dp += len; 352 cpp++; 353 envc++; 354 } 355 } 356 357 dp = (char *)ALIGN(dp); 358 359 szsigcode = pack.ep_emul->e_esigcode - pack.ep_emul->e_sigcode; 360 361 /* Now check if args & environ fit into new stack */ 362 len = ((argc + envc + 2 + pack.ep_emul->e_arglen) * sizeof(char *) + 363 sizeof(long) + dp + STACKGAPLEN + szsigcode + 364 sizeof(struct ps_strings)) - argp; 365 366 len = ALIGN(len); /* make the stack "safely" aligned */ 367 368 if (len > pack.ep_ssize) { /* in effect, compare to initial limit */ 369 error = ENOMEM; 370 goto bad; 371 } 372 373 /* adjust "active stack depth" for process VSZ */ 374 pack.ep_ssize = len; /* maybe should go elsewhere, but... */ 375 376 /* 377 * Prepare vmspace for remapping. Note that uvmspace_exec can replace 378 * p_vmspace! 379 */ 380 #if defined(UVM) 381 uvmspace_exec(p); 382 #else 383 /* Unmap old program */ 384 #ifdef sparc 385 kill_user_windows(p); /* before stack addresses go away */ 386 #endif 387 /* Kill shared memory and unmap old program */ 388 #ifdef SYSVSHM 389 if (vm->vm_shm) 390 shmexit(p); 391 #endif 392 vm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, 393 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); 394 #endif 395 396 vm = p->p_vmspace; 397 /* Now map address space */ 398 vm->vm_taddr = (char *)pack.ep_taddr; 399 vm->vm_tsize = btoc(pack.ep_tsize); 400 vm->vm_daddr = (char *)pack.ep_daddr; 401 vm->vm_dsize = btoc(pack.ep_dsize); 402 vm->vm_ssize = btoc(pack.ep_ssize); 403 vm->vm_maxsaddr = (char *)pack.ep_maxsaddr; 404 405 /* create the new process's VM space by running the vmcmds */ 406 #ifdef DIAGNOSTIC 407 if (pack.ep_vmcmds.evs_used == 0) 408 panic("execve: no vmcmds"); 409 #endif 410 for (i = 0; i < pack.ep_vmcmds.evs_used && !error; i++) { 411 struct exec_vmcmd *vcp; 412 413 vcp = &pack.ep_vmcmds.evs_cmds[i]; 414 error = (*vcp->ev_proc)(p, vcp); 415 } 416 417 /* free the vmspace-creation commands, and release their references */ 418 kill_vmcmds(&pack.ep_vmcmds); 419 420 /* if an error happened, deallocate and punt */ 421 if (error) 422 goto exec_abort; 423 424 /* remember information about the process */ 425 arginfo.ps_nargvstr = argc; 426 arginfo.ps_nenvstr = envc; 427 428 stack = (char *)(USRSTACK - len); 429 /* Now copy argc, args & environ to new stack */ 430 if (!(*pack.ep_emul->e_copyargs)(&pack, &arginfo, stack, argp)) 431 goto exec_abort; 432 433 /* copy out the process's ps_strings structure */ 434 if (copyout(&arginfo, (char *)PS_STRINGS, sizeof(arginfo))) 435 goto exec_abort; 436 437 /* copy out the process's signal trapoline code */ 438 if (szsigcode && copyout((char *)pack.ep_emul->e_sigcode, 439 ((char *)PS_STRINGS) - szsigcode, szsigcode)) 440 goto exec_abort; 441 442 fdcloseexec(p); /* handle close on exec */ 443 execsigs(p); /* reset catched signals */ 444 445 /* set command name & other accounting info */ 446 len = min(nid.ni_cnd.cn_namelen, MAXCOMLEN); 447 bcopy(nid.ni_cnd.cn_nameptr, p->p_comm, len); 448 p->p_comm[len] = 0; 449 p->p_acflag &= ~AFORK; 450 451 /* record proc's vnode, for use by procfs and others */ 452 if (p->p_textvp) 453 vrele(p->p_textvp); 454 VREF(pack.ep_vp); 455 p->p_textvp = pack.ep_vp; 456 457 p->p_flag |= P_EXEC; 458 if (p->p_flag & P_PPWAIT) { 459 p->p_flag &= ~P_PPWAIT; 460 wakeup((caddr_t)p->p_pptr); 461 } 462 463 /* 464 * If process does execve() while it has euid/uid or egid/gid 465 * which are mismatched, it remains P_SUGIDEXEC. 466 */ 467 if (p->p_ucred->cr_uid == p->p_cred->p_ruid && 468 p->p_ucred->cr_gid == p->p_cred->p_rgid) 469 p->p_flag &= ~P_SUGIDEXEC; 470 471 /* 472 * deal with set[ug]id. 473 * MNT_NOEXEC and P_TRACED have already been used to disable s[ug]id. 474 */ 475 if ((attr.va_mode & (VSUID | VSGID))) { 476 int i; 477 478 #ifdef KTRACE 479 /* 480 * If process is being ktraced, turn off - unless 481 * root set it. 482 */ 483 if (p->p_tracep && !(p->p_traceflag & KTRFAC_ROOT)) { 484 p->p_traceflag = 0; 485 vrele(p->p_tracep); 486 p->p_tracep = NULL; 487 } 488 #endif 489 p->p_ucred = crcopy(cred); 490 if (attr.va_mode & VSUID) 491 p->p_ucred->cr_uid = attr.va_uid; 492 if (attr.va_mode & VSGID) 493 p->p_ucred->cr_gid = attr.va_gid; 494 p->p_flag |= P_SUGID; 495 p->p_flag |= P_SUGIDEXEC; 496 497 /* 498 * XXX For setuid processes, attempt to ensure that 499 * stdin, stdout, and stderr are already allocated. 500 * We do not want userland to accidentally allocate 501 * descriptors in this range which has implied meaning 502 * to libc. 503 */ 504 for (i = 0; i < 3; i++) { 505 extern struct fileops vnops; 506 struct nameidata nd; 507 struct file *fp; 508 int indx; 509 short flags; 510 511 flags = FREAD | (i == 0 ? 0 : FWRITE); 512 513 if (p->p_fd->fd_ofiles[i] == NULL) { 514 if ((error = falloc(p, &fp, &indx)) != 0) 515 continue; 516 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, 517 "/dev/null", p); 518 if ((error = vn_open(&nd, flags, 0)) != 0) { 519 ffree(fp); 520 p->p_fd->fd_ofiles[indx] = NULL; 521 break; 522 } 523 fp->f_flag = flags; 524 fp->f_type = DTYPE_VNODE; 525 fp->f_ops = &vnops; 526 fp->f_data = (caddr_t)nd.ni_vp; 527 VOP_UNLOCK(nd.ni_vp, 0, p); 528 } 529 } 530 531 } else 532 p->p_flag &= ~P_SUGID; 533 p->p_cred->p_svuid = p->p_ucred->cr_uid; 534 p->p_cred->p_svgid = p->p_ucred->cr_gid; 535 536 if (p->p_flag & P_SUGIDEXEC) { 537 int i, s = splclock(); 538 539 untimeout(realitexpire, (void *)p); 540 timerclear(&p->p_realtimer.it_interval); 541 timerclear(&p->p_realtimer.it_value); 542 for (i = 0; i < sizeof(p->p_stats->p_timer) / 543 sizeof(p->p_stats->p_timer[0]); i++) { 544 timerclear(&p->p_stats->p_timer[i].it_interval); 545 timerclear(&p->p_stats->p_timer[i].it_value); 546 } 547 splx(s); 548 } 549 550 #if defined(UVM) 551 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 552 #else 553 kmem_free_wakeup(exec_map, (vm_offset_t)argp, NCARGS); 554 #endif 555 556 FREE(nid.ni_cnd.cn_pnbuf, M_NAMEI); 557 VOP_CLOSE(pack.ep_vp, FREAD, cred, p); 558 vput(pack.ep_vp); 559 560 /* setup new registers and do misc. setup. */ 561 if(pack.ep_emul->e_fixup != NULL) { 562 if((*pack.ep_emul->e_fixup)(p, &pack) != 0) 563 goto free_pack_abort; 564 } 565 (*pack.ep_emul->e_setregs)(p, &pack, (u_long)stack, retval); 566 567 if (p->p_flag & P_TRACED) 568 psignal(p, SIGTRAP); 569 570 p->p_emul = pack.ep_emul; 571 FREE(pack.ep_hdr, M_EXEC); 572 573 #ifdef KTRACE 574 if (KTRPOINT(p, KTR_EMUL)) 575 ktremul(p->p_tracep, p->p_emul->e_name); 576 #endif 577 return (0); 578 579 bad: 580 /* free the vmspace-creation commands, and release their references */ 581 kill_vmcmds(&pack.ep_vmcmds); 582 /* kill any opened file descriptor, if necessary */ 583 if (pack.ep_flags & EXEC_HASFD) { 584 pack.ep_flags &= ~EXEC_HASFD; 585 (void) fdrelease(p, pack.ep_fd); 586 } 587 /* close and put the exec'd file */ 588 VOP_CLOSE(pack.ep_vp, FREAD, cred, p); 589 vput(pack.ep_vp); 590 FREE(nid.ni_cnd.cn_pnbuf, M_NAMEI); 591 #if defined(UVM) 592 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 593 #else 594 kmem_free_wakeup(exec_map, (vm_offset_t) argp, NCARGS); 595 #endif 596 597 freehdr: 598 FREE(pack.ep_hdr, M_EXEC); 599 return (error); 600 601 exec_abort: 602 /* 603 * the old process doesn't exist anymore. exit gracefully. 604 * get rid of the (new) address space we have created, if any, get rid 605 * of our namei data and vnode, and exit noting failure 606 */ 607 #if defined(UVM) 608 uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, 609 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); 610 #else 611 vm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, 612 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); 613 #endif 614 if (pack.ep_emul_arg) 615 FREE(pack.ep_emul_arg, M_TEMP); 616 FREE(nid.ni_cnd.cn_pnbuf, M_NAMEI); 617 VOP_CLOSE(pack.ep_vp, FREAD, cred, p); 618 vput(pack.ep_vp); 619 #if defined(UVM) 620 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 621 #else 622 kmem_free_wakeup(exec_map, (vm_offset_t) argp, NCARGS); 623 #endif 624 625 free_pack_abort: 626 FREE(pack.ep_hdr, M_EXEC); 627 exit1(p, W_EXITCODE(0, SIGABRT)); 628 exit1(p, -1); 629 630 /* NOTREACHED */ 631 return (0); 632 } 633 634 635 void * 636 copyargs(pack, arginfo, stack, argp) 637 struct exec_package *pack; 638 struct ps_strings *arginfo; 639 void *stack; 640 void *argp; 641 { 642 char **cpp = stack; 643 char *dp, *sp; 644 size_t len; 645 void *nullp = NULL; 646 int argc = arginfo->ps_nargvstr; 647 int envc = arginfo->ps_nenvstr; 648 649 if (copyout(&argc, cpp++, sizeof(argc))) 650 return (NULL); 651 652 dp = (char *) (cpp + argc + envc + 2 + pack->ep_emul->e_arglen); 653 sp = argp; 654 655 /* XXX don't copy them out, remap them! */ 656 arginfo->ps_argvstr = cpp; /* remember location of argv for later */ 657 658 for (; --argc >= 0; sp += len, dp += len) 659 if (copyout(&dp, cpp++, sizeof(dp)) || 660 copyoutstr(sp, dp, ARG_MAX, &len)) 661 return (NULL); 662 663 if (copyout(&nullp, cpp++, sizeof(nullp))) 664 return (NULL); 665 666 arginfo->ps_envstr = cpp; /* remember location of envp for later */ 667 668 for (; --envc >= 0; sp += len, dp += len) 669 if (copyout(&dp, cpp++, sizeof(dp)) || 670 copyoutstr(sp, dp, ARG_MAX, &len)) 671 return (NULL); 672 673 if (copyout(&nullp, cpp++, sizeof(nullp))) 674 return (NULL); 675 676 return (cpp); 677 } 678