1 /* $OpenBSD: kern_exec.c,v 1.100 2006/11/15 17:25:40 jmc 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/pool.h> 44 #include <sys/namei.h> 45 #include <sys/vnode.h> 46 #include <sys/file.h> 47 #include <sys/acct.h> 48 #include <sys/exec.h> 49 #include <sys/ktrace.h> 50 #include <sys/resourcevar.h> 51 #include <sys/wait.h> 52 #include <sys/mman.h> 53 #include <sys/signalvar.h> 54 #include <sys/stat.h> 55 #include <sys/conf.h> 56 #ifdef SYSVSHM 57 #include <sys/shm.h> 58 #endif 59 60 #include <sys/syscallargs.h> 61 62 #include <uvm/uvm_extern.h> 63 64 #include <machine/cpu.h> 65 #include <machine/reg.h> 66 67 #include <dev/rndvar.h> 68 69 #include "systrace.h" 70 71 #if NSYSTRACE > 0 72 #include <dev/systrace.h> 73 #endif 74 75 /* 76 * Map the shared signal code. 77 */ 78 int exec_sigcode_map(struct proc *, struct emul *); 79 80 /* 81 * stackgap_random specifies if the stackgap should have a random size added 82 * to it. Must be a n^2. If non-zero, the stack gap will be calculated as: 83 * (arc4random() * ALIGNBYTES) & (stackgap_random - 1) + STACKGAPLEN. 84 */ 85 int stackgap_random = STACKGAP_RANDOM; 86 87 /* 88 * check exec: 89 * given an "executable" described in the exec package's namei info, 90 * see what we can do with it. 91 * 92 * ON ENTRY: 93 * exec package with appropriate namei info 94 * proc pointer of exec'ing proc 95 * NO SELF-LOCKED VNODES 96 * 97 * ON EXIT: 98 * error: nothing held, etc. exec header still allocated. 99 * ok: filled exec package, one locked vnode. 100 * 101 * EXEC SWITCH ENTRY: 102 * Locked vnode to check, exec package, proc. 103 * 104 * EXEC SWITCH EXIT: 105 * ok: return 0, filled exec package, one locked vnode. 106 * error: destructive: 107 * everything deallocated execept exec header. 108 * non-destructive: 109 * error code, locked vnode, exec header unmodified 110 */ 111 int 112 check_exec(struct proc *p, struct exec_package *epp) 113 { 114 int error, i; 115 struct vnode *vp; 116 struct nameidata *ndp; 117 size_t resid; 118 119 ndp = epp->ep_ndp; 120 ndp->ni_cnd.cn_nameiop = LOOKUP; 121 ndp->ni_cnd.cn_flags = FOLLOW | LOCKLEAF | SAVENAME; 122 /* first get the vnode */ 123 if ((error = namei(ndp)) != 0) 124 return (error); 125 epp->ep_vp = vp = ndp->ni_vp; 126 127 /* check for regular file */ 128 if (vp->v_type == VDIR) { 129 error = EISDIR; 130 goto bad1; 131 } 132 if (vp->v_type != VREG) { 133 error = EACCES; 134 goto bad1; 135 } 136 137 /* get attributes */ 138 if ((error = VOP_GETATTR(vp, epp->ep_vap, p->p_ucred, p)) != 0) 139 goto bad1; 140 141 /* Check mount point */ 142 if (vp->v_mount->mnt_flag & MNT_NOEXEC) { 143 error = EACCES; 144 goto bad1; 145 } 146 147 if ((vp->v_mount->mnt_flag & MNT_NOSUID)) 148 epp->ep_vap->va_mode &= ~(VSUID | VSGID); 149 150 /* check access. for root we have to see if any exec bit on */ 151 if ((error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p)) != 0) 152 goto bad1; 153 if ((epp->ep_vap->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0) { 154 error = EACCES; 155 goto bad1; 156 } 157 158 /* try to open it */ 159 if ((error = VOP_OPEN(vp, FREAD, p->p_ucred, p)) != 0) 160 goto bad1; 161 162 /* unlock vp, we need it unlocked from here */ 163 VOP_UNLOCK(vp, 0, p); 164 165 /* now we have the file, get the exec header */ 166 error = vn_rdwr(UIO_READ, vp, epp->ep_hdr, epp->ep_hdrlen, 0, 167 UIO_SYSSPACE, 0, p->p_ucred, &resid, p); 168 if (error) 169 goto bad2; 170 epp->ep_hdrvalid = epp->ep_hdrlen - resid; 171 172 /* 173 * set up the vmcmds for creation of the process 174 * address space 175 */ 176 error = ENOEXEC; 177 for (i = 0; i < nexecs && error != 0; i++) { 178 int newerror; 179 180 if (execsw[i].es_check == NULL) 181 continue; 182 newerror = (*execsw[i].es_check)(p, epp); 183 if (!newerror && !(epp->ep_emul->e_flags & EMUL_ENABLED)) 184 newerror = EPERM; 185 /* make sure the first "interesting" error code is saved. */ 186 if (!newerror || error == ENOEXEC) 187 error = newerror; 188 if (epp->ep_flags & EXEC_DESTR && error != 0) 189 return (error); 190 } 191 if (!error) { 192 /* check that entry point is sane */ 193 if (epp->ep_entry > VM_MAXUSER_ADDRESS) { 194 error = ENOEXEC; 195 } 196 197 /* check limits */ 198 if ((epp->ep_tsize > MAXTSIZ) || 199 (epp->ep_dsize > p->p_rlimit[RLIMIT_DATA].rlim_cur)) 200 error = ENOMEM; 201 202 if (!error) 203 return (0); 204 } 205 206 /* 207 * free any vmspace-creation commands, 208 * and release their references 209 */ 210 kill_vmcmds(&epp->ep_vmcmds); 211 212 bad2: 213 /* 214 * close the vnode, free the pathname buf, and punt. 215 */ 216 vn_close(vp, FREAD, p->p_ucred, p); 217 pool_put(&namei_pool, ndp->ni_cnd.cn_pnbuf); 218 return (error); 219 220 bad1: 221 /* 222 * free the namei pathname buffer, and put the vnode 223 * (which we don't yet have open). 224 */ 225 pool_put(&namei_pool, ndp->ni_cnd.cn_pnbuf); 226 vput(vp); 227 return (error); 228 } 229 230 /* 231 * exec system call 232 */ 233 /* ARGSUSED */ 234 int 235 sys_execve(struct proc *p, void *v, register_t *retval) 236 { 237 struct sys_execve_args /* { 238 syscallarg(const char *) path; 239 syscallarg(char *const *) argp; 240 syscallarg(char *const *) envp; 241 } */ *uap = v; 242 int error; 243 struct exec_package pack; 244 struct nameidata nid; 245 struct vattr attr; 246 struct ucred *cred = p->p_ucred; 247 char *argp; 248 char * const *cpp, *dp, *sp; 249 long argc, envc; 250 size_t len, sgap; 251 #ifdef MACHINE_STACK_GROWS_UP 252 size_t slen; 253 #endif 254 char *stack; 255 struct ps_strings arginfo; 256 struct vmspace *vm = p->p_vmspace; 257 char **tmpfap; 258 extern struct emul emul_native; 259 #if NSYSTRACE > 0 260 int wassugid = 261 ISSET(p->p_flag, P_SUGID) || ISSET(p->p_flag, P_SUGIDEXEC); 262 size_t pathbuflen; 263 #endif 264 char *pathbuf = NULL; 265 266 /* 267 * Cheap solution to complicated problems. 268 * Mark this process as "leave me alone, I'm execing". 269 */ 270 p->p_flag |= P_INEXEC; 271 272 #if NSYSTRACE > 0 273 if (ISSET(p->p_flag, P_SYSTRACE)) { 274 systrace_execve0(p); 275 pathbuf = pool_get(&namei_pool, PR_WAITOK); 276 error = copyinstr(SCARG(uap, path), pathbuf, MAXPATHLEN, 277 &pathbuflen); 278 if (error != 0) 279 goto clrflag; 280 } 281 #endif 282 if (pathbuf != NULL) { 283 NDINIT(&nid, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, p); 284 } else { 285 NDINIT(&nid, LOOKUP, NOFOLLOW, UIO_USERSPACE, 286 SCARG(uap, path), p); 287 } 288 289 /* 290 * initialize the fields of the exec package. 291 */ 292 if (pathbuf != NULL) 293 pack.ep_name = pathbuf; 294 else 295 pack.ep_name = (char *)SCARG(uap, path); 296 pack.ep_hdr = malloc(exec_maxhdrsz, M_EXEC, M_WAITOK); 297 pack.ep_hdrlen = exec_maxhdrsz; 298 pack.ep_hdrvalid = 0; 299 pack.ep_ndp = &nid; 300 pack.ep_interp = NULL; 301 pack.ep_emul_arg = NULL; 302 VMCMDSET_INIT(&pack.ep_vmcmds); 303 pack.ep_vap = &attr; 304 pack.ep_emul = &emul_native; 305 pack.ep_flags = 0; 306 307 /* see if we can run it. */ 308 if ((error = check_exec(p, &pack)) != 0) { 309 goto freehdr; 310 } 311 312 /* XXX -- THE FOLLOWING SECTION NEEDS MAJOR CLEANUP */ 313 314 /* allocate an argument buffer */ 315 argp = (char *) uvm_km_valloc_wait(exec_map, NCARGS); 316 #ifdef DIAGNOSTIC 317 if (argp == NULL) 318 panic("execve: argp == NULL"); 319 #endif 320 dp = argp; 321 argc = 0; 322 323 /* copy the fake args list, if there's one, freeing it as we go */ 324 if (pack.ep_flags & EXEC_HASARGL) { 325 tmpfap = pack.ep_fa; 326 while (*tmpfap != NULL) { 327 char *cp; 328 329 cp = *tmpfap; 330 while (*cp) 331 *dp++ = *cp++; 332 dp++; 333 334 free(*tmpfap, M_EXEC); 335 tmpfap++; argc++; 336 } 337 FREE(pack.ep_fa, M_EXEC); 338 pack.ep_flags &= ~EXEC_HASARGL; 339 } 340 341 /* Now get argv & environment */ 342 if (!(cpp = SCARG(uap, argp))) { 343 error = EFAULT; 344 goto bad; 345 } 346 347 if (pack.ep_flags & EXEC_SKIPARG) 348 cpp++; 349 350 while (1) { 351 len = argp + ARG_MAX - dp; 352 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0) 353 goto bad; 354 if (!sp) 355 break; 356 if ((error = copyinstr(sp, dp, len, &len)) != 0) { 357 if (error == ENAMETOOLONG) 358 error = E2BIG; 359 goto bad; 360 } 361 dp += len; 362 cpp++; 363 argc++; 364 } 365 366 envc = 0; 367 /* environment does not need to be there */ 368 if ((cpp = SCARG(uap, envp)) != NULL ) { 369 while (1) { 370 len = argp + ARG_MAX - dp; 371 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0) 372 goto bad; 373 if (!sp) 374 break; 375 if ((error = copyinstr(sp, dp, len, &len)) != 0) { 376 if (error == ENAMETOOLONG) 377 error = E2BIG; 378 goto bad; 379 } 380 dp += len; 381 cpp++; 382 envc++; 383 } 384 } 385 386 dp = (char *)ALIGN(dp); 387 388 sgap = STACKGAPLEN; 389 if (stackgap_random != 0) 390 sgap += (arc4random() * ALIGNBYTES) & (stackgap_random - 1); 391 /* Now check if args & environ fit into new stack */ 392 len = ((argc + envc + 2 + pack.ep_emul->e_arglen) * sizeof(char *) + 393 sizeof(long) + dp + sgap + sizeof(struct ps_strings)) - argp; 394 395 len = ALIGN(len); /* make the stack "safely" aligned */ 396 397 if (len > pack.ep_ssize) { /* in effect, compare to initial limit */ 398 error = ENOMEM; 399 goto bad; 400 } 401 402 /* adjust "active stack depth" for process VSZ */ 403 pack.ep_ssize = len; /* maybe should go elsewhere, but... */ 404 405 /* 406 * Prepare vmspace for remapping. Note that uvmspace_exec can replace 407 * p_vmspace! 408 */ 409 uvmspace_exec(p, VM_MIN_ADDRESS, VM_MAXUSER_ADDRESS); 410 411 vm = p->p_vmspace; 412 /* Now map address space */ 413 vm->vm_taddr = (char *)pack.ep_taddr; 414 vm->vm_tsize = btoc(pack.ep_tsize); 415 vm->vm_daddr = (char *)pack.ep_daddr; 416 vm->vm_dsize = btoc(pack.ep_dsize); 417 vm->vm_dused = 0; 418 vm->vm_ssize = btoc(pack.ep_ssize); 419 vm->vm_maxsaddr = (char *)pack.ep_maxsaddr; 420 vm->vm_minsaddr = (char *)pack.ep_minsaddr; 421 422 /* create the new process's VM space by running the vmcmds */ 423 #ifdef DIAGNOSTIC 424 if (pack.ep_vmcmds.evs_used == 0) 425 panic("execve: no vmcmds"); 426 #endif 427 error = exec_process_vmcmds(p, &pack); 428 429 /* if an error happened, deallocate and punt */ 430 if (error) 431 goto exec_abort; 432 433 /* remember information about the process */ 434 arginfo.ps_nargvstr = argc; 435 arginfo.ps_nenvstr = envc; 436 437 #ifdef MACHINE_STACK_GROWS_UP 438 stack = (char *)USRSTACK + sizeof(arginfo); 439 slen = len - sizeof(arginfo); 440 #else 441 stack = (char *)(USRSTACK - len); 442 #endif 443 /* Now copy argc, args & environ to new stack */ 444 if (!(*pack.ep_emul->e_copyargs)(&pack, &arginfo, stack, argp)) 445 goto exec_abort; 446 447 /* copy out the process's ps_strings structure */ 448 if (copyout(&arginfo, (char *)PS_STRINGS, sizeof(arginfo))) 449 goto exec_abort; 450 451 stopprofclock(p); /* stop profiling */ 452 fdcloseexec(p); /* handle close on exec */ 453 execsigs(p); /* reset caught signals */ 454 455 /* set command name & other accounting info */ 456 len = min(nid.ni_cnd.cn_namelen, MAXCOMLEN); 457 bcopy(nid.ni_cnd.cn_nameptr, p->p_comm, len); 458 p->p_comm[len] = 0; 459 p->p_acflag &= ~AFORK; 460 461 /* record proc's vnode, for use by procfs and others */ 462 if (p->p_textvp) 463 vrele(p->p_textvp); 464 VREF(pack.ep_vp); 465 p->p_textvp = pack.ep_vp; 466 467 p->p_flag |= P_EXEC; 468 if (p->p_flag & P_PPWAIT) { 469 p->p_flag &= ~P_PPWAIT; 470 wakeup((caddr_t)p->p_pptr); 471 } 472 473 /* 474 * If process does execve() while it has a mismatched real, 475 * effective, or saved uid/gid, we set P_SUGIDEXEC. 476 */ 477 if (p->p_ucred->cr_uid != p->p_cred->p_ruid || 478 p->p_ucred->cr_uid != p->p_cred->p_svuid || 479 p->p_ucred->cr_gid != p->p_cred->p_rgid || 480 p->p_ucred->cr_gid != p->p_cred->p_svgid) 481 p->p_flag |= P_SUGIDEXEC; 482 else 483 p->p_flag &= ~P_SUGIDEXEC; 484 485 /* 486 * deal with set[ug]id. 487 * MNT_NOEXEC has already been used to disable s[ug]id. 488 */ 489 if ((attr.va_mode & (VSUID | VSGID)) && proc_cansugid(p)) { 490 int i; 491 492 p->p_flag |= P_SUGID; 493 p->p_flag |= P_SUGIDEXEC; 494 495 #ifdef KTRACE 496 /* 497 * If process is being ktraced, turn off - unless 498 * root set it. 499 */ 500 if (p->p_tracep && !(p->p_traceflag & KTRFAC_ROOT)) { 501 p->p_traceflag = 0; 502 ktrsettracevnode(p, NULL); 503 } 504 #endif 505 p->p_ucred = crcopy(cred); 506 if (attr.va_mode & VSUID) 507 p->p_ucred->cr_uid = attr.va_uid; 508 if (attr.va_mode & VSGID) 509 p->p_ucred->cr_gid = attr.va_gid; 510 511 /* 512 * For set[ug]id processes, a few caveats apply to 513 * stdin, stdout, and stderr. 514 */ 515 for (i = 0; i < 3; i++) { 516 struct file *fp = NULL; 517 518 /* 519 * NOTE - This will never return NULL because of 520 * immature fds. The file descriptor table is not 521 * shared because we're suid. 522 */ 523 fp = fd_getfile(p->p_fd, i); 524 #ifdef PROCFS 525 /* 526 * Close descriptors that are writing to procfs. 527 */ 528 if (fp && fp->f_type == DTYPE_VNODE && 529 ((struct vnode *)(fp->f_data))->v_tag == VT_PROCFS && 530 (fp->f_flag & FWRITE)) { 531 fdrelease(p, i); 532 fp = NULL; 533 } 534 #endif 535 536 /* 537 * Ensure that stdin, stdout, and stderr are already 538 * allocated. We do not want userland to accidentally 539 * allocate descriptors in this range which has implied 540 * meaning to libc. 541 */ 542 if (fp == NULL) { 543 short flags = FREAD | (i == 0 ? 0 : FWRITE); 544 struct vnode *vp; 545 int indx; 546 547 if ((error = falloc(p, &fp, &indx)) != 0) 548 goto exec_abort; 549 #ifdef DIAGNOSTIC 550 if (indx != i) 551 panic("sys_execve: falloc indx != i"); 552 #endif 553 if ((error = cdevvp(getnulldev(), &vp)) != 0) { 554 fdremove(p->p_fd, indx); 555 closef(fp, p); 556 goto exec_abort; 557 } 558 if ((error = VOP_OPEN(vp, flags, p->p_ucred, p)) != 0) { 559 fdremove(p->p_fd, indx); 560 closef(fp, p); 561 vrele(vp); 562 goto exec_abort; 563 } 564 if (flags & FWRITE) 565 vp->v_writecount++; 566 fp->f_flag = flags; 567 fp->f_type = DTYPE_VNODE; 568 fp->f_ops = &vnops; 569 fp->f_data = (caddr_t)vp; 570 FILE_SET_MATURE(fp); 571 } 572 } 573 } else 574 p->p_flag &= ~P_SUGID; 575 p->p_cred->p_svuid = p->p_ucred->cr_uid; 576 p->p_cred->p_svgid = p->p_ucred->cr_gid; 577 578 if (p->p_flag & P_SUGIDEXEC) { 579 int i, s = splclock(); 580 581 timeout_del(&p->p_realit_to); 582 timerclear(&p->p_realtimer.it_interval); 583 timerclear(&p->p_realtimer.it_value); 584 for (i = 0; i < sizeof(p->p_stats->p_timer) / 585 sizeof(p->p_stats->p_timer[0]); i++) { 586 timerclear(&p->p_stats->p_timer[i].it_interval); 587 timerclear(&p->p_stats->p_timer[i].it_value); 588 } 589 splx(s); 590 } 591 592 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 593 594 pool_put(&namei_pool, nid.ni_cnd.cn_pnbuf); 595 vn_close(pack.ep_vp, FREAD, cred, p); 596 597 /* 598 * notify others that we exec'd 599 */ 600 KNOTE(&p->p_klist, NOTE_EXEC); 601 602 /* setup new registers and do misc. setup. */ 603 if (pack.ep_emul->e_fixup != NULL) { 604 if ((*pack.ep_emul->e_fixup)(p, &pack) != 0) 605 goto free_pack_abort; 606 } 607 #ifdef MACHINE_STACK_GROWS_UP 608 (*pack.ep_emul->e_setregs)(p, &pack, (u_long)stack + slen, retval); 609 #else 610 (*pack.ep_emul->e_setregs)(p, &pack, (u_long)stack, retval); 611 #endif 612 613 /* map the process's signal trampoline code */ 614 if (exec_sigcode_map(p, pack.ep_emul)) 615 goto free_pack_abort; 616 617 if (p->p_flag & P_TRACED) 618 psignal(p, SIGTRAP); 619 620 free(pack.ep_hdr, M_EXEC); 621 622 /* 623 * Call emulation specific exec hook. This can setup per-process 624 * p->p_emuldata or do any other per-process stuff an emulation needs. 625 * 626 * If we are executing process of different emulation than the 627 * original forked process, call e_proc_exit() of the old emulation 628 * first, then e_proc_exec() of new emulation. If the emulation is 629 * same, the exec hook code should deallocate any old emulation 630 * resources held previously by this process. 631 */ 632 if (p->p_emul && p->p_emul->e_proc_exit && 633 p->p_emul != pack.ep_emul) 634 (*p->p_emul->e_proc_exit)(p); 635 636 p->p_descfd = 255; 637 if ((pack.ep_flags & EXEC_HASFD) && pack.ep_fd < 255) 638 p->p_descfd = pack.ep_fd; 639 640 /* 641 * Call exec hook. Emulation code may NOT store reference to anything 642 * from &pack. 643 */ 644 if (pack.ep_emul->e_proc_exec) 645 (*pack.ep_emul->e_proc_exec)(p, &pack); 646 647 /* update p_emul, the old value is no longer needed */ 648 p->p_emul = pack.ep_emul; 649 650 #ifdef KTRACE 651 if (KTRPOINT(p, KTR_EMUL)) 652 ktremul(p, p->p_emul->e_name); 653 #endif 654 655 p->p_flag &= ~P_INEXEC; 656 657 #if NSYSTRACE > 0 658 if (ISSET(p->p_flag, P_SYSTRACE) && 659 wassugid && !ISSET(p->p_flag, P_SUGID) && 660 !ISSET(p->p_flag, P_SUGIDEXEC)) 661 systrace_execve1(pathbuf, p); 662 #endif 663 664 if (pathbuf != NULL) 665 pool_put(&namei_pool, pathbuf); 666 667 return (0); 668 669 bad: 670 /* free the vmspace-creation commands, and release their references */ 671 kill_vmcmds(&pack.ep_vmcmds); 672 /* kill any opened file descriptor, if necessary */ 673 if (pack.ep_flags & EXEC_HASFD) { 674 pack.ep_flags &= ~EXEC_HASFD; 675 (void) fdrelease(p, pack.ep_fd); 676 } 677 if (pack.ep_interp != NULL) 678 pool_put(&namei_pool, pack.ep_interp); 679 if (pack.ep_emul_arg != NULL) 680 FREE(pack.ep_emul_arg, M_TEMP); 681 /* close and put the exec'd file */ 682 vn_close(pack.ep_vp, FREAD, cred, p); 683 pool_put(&namei_pool, nid.ni_cnd.cn_pnbuf); 684 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 685 686 freehdr: 687 free(pack.ep_hdr, M_EXEC); 688 #if NSYSTRACE > 0 689 clrflag: 690 #endif 691 p->p_flag &= ~P_INEXEC; 692 693 if (pathbuf != NULL) 694 pool_put(&namei_pool, pathbuf); 695 696 return (error); 697 698 exec_abort: 699 /* 700 * the old process doesn't exist anymore. exit gracefully. 701 * get rid of the (new) address space we have created, if any, get rid 702 * of our namei data and vnode, and exit noting failure 703 */ 704 uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, 705 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); 706 if (pack.ep_interp != NULL) 707 pool_put(&namei_pool, pack.ep_interp); 708 if (pack.ep_emul_arg != NULL) 709 FREE(pack.ep_emul_arg, M_TEMP); 710 pool_put(&namei_pool, nid.ni_cnd.cn_pnbuf); 711 vn_close(pack.ep_vp, FREAD, cred, p); 712 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 713 714 free_pack_abort: 715 free(pack.ep_hdr, M_EXEC); 716 exit1(p, W_EXITCODE(0, SIGABRT), EXIT_NORMAL); 717 718 /* NOTREACHED */ 719 p->p_flag &= ~P_INEXEC; 720 if (pathbuf != NULL) 721 pool_put(&namei_pool, pathbuf); 722 723 return (0); 724 } 725 726 727 void * 728 copyargs(struct exec_package *pack, struct ps_strings *arginfo, void *stack, 729 void *argp) 730 { 731 char **cpp = stack; 732 char *dp, *sp; 733 size_t len; 734 void *nullp = NULL; 735 long argc = arginfo->ps_nargvstr; 736 int envc = arginfo->ps_nenvstr; 737 738 if (copyout(&argc, cpp++, sizeof(argc))) 739 return (NULL); 740 741 dp = (char *) (cpp + argc + envc + 2 + pack->ep_emul->e_arglen); 742 sp = argp; 743 744 /* XXX don't copy them out, remap them! */ 745 arginfo->ps_argvstr = cpp; /* remember location of argv for later */ 746 747 for (; --argc >= 0; sp += len, dp += len) 748 if (copyout(&dp, cpp++, sizeof(dp)) || 749 copyoutstr(sp, dp, ARG_MAX, &len)) 750 return (NULL); 751 752 if (copyout(&nullp, cpp++, sizeof(nullp))) 753 return (NULL); 754 755 arginfo->ps_envstr = cpp; /* remember location of envp for later */ 756 757 for (; --envc >= 0; sp += len, dp += len) 758 if (copyout(&dp, cpp++, sizeof(dp)) || 759 copyoutstr(sp, dp, ARG_MAX, &len)) 760 return (NULL); 761 762 if (copyout(&nullp, cpp++, sizeof(nullp))) 763 return (NULL); 764 765 return (cpp); 766 } 767 768 int 769 exec_sigcode_map(struct proc *p, struct emul *e) 770 { 771 vsize_t sz; 772 773 sz = (vaddr_t)e->e_esigcode - (vaddr_t)e->e_sigcode; 774 775 /* 776 * If we don't have a sigobject for this emulation, create one. 777 * 778 * sigobject is an anonymous memory object (just like SYSV shared 779 * memory) that we keep a permanent reference to and that we map 780 * in all processes that need this sigcode. The creation is simple, 781 * we create an object, add a permanent reference to it, map it in 782 * kernel space, copy out the sigcode to it and unmap it. 783 * Then we map it with PROT_READ|PROT_EXEC into the process just 784 * the way sys_mmap would map it. 785 */ 786 if (e->e_sigobject == NULL) { 787 vaddr_t va; 788 int r; 789 790 e->e_sigobject = uao_create(sz, 0); 791 uao_reference(e->e_sigobject); /* permanent reference */ 792 793 va = vm_map_min(kernel_map); /* hint */ 794 if ((r = uvm_map(kernel_map, &va, round_page(sz), e->e_sigobject, 795 0, 0, UVM_MAPFLAG(UVM_PROT_RW, UVM_PROT_RW, 796 UVM_INH_SHARE, UVM_ADV_RANDOM, 0)))) { 797 printf("kernel mapping failed %d\n", r); 798 uao_detach(e->e_sigobject); 799 return (ENOMEM); 800 } 801 memcpy((void *)va, e->e_sigcode, sz); 802 uvm_unmap(kernel_map, va, va + round_page(sz)); 803 } 804 805 /* Just a hint to uvm_mmap where to put it. */ 806 p->p_sigcode = uvm_map_hint(p, VM_PROT_READ|VM_PROT_EXECUTE); 807 uao_reference(e->e_sigobject); 808 if (uvm_map(&p->p_vmspace->vm_map, &p->p_sigcode, round_page(sz), 809 e->e_sigobject, 0, 0, UVM_MAPFLAG(UVM_PROT_RX, UVM_PROT_RX, 810 UVM_INH_SHARE, UVM_ADV_RANDOM, 0))) { 811 printf("user mapping failed\n"); 812 uao_detach(e->e_sigobject); 813 return (ENOMEM); 814 } 815 816 return (0); 817 } 818