1 /* $OpenBSD: kern_exec.c,v 1.109 2009/01/04 00:28:42 thib 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 atomic_setbits_int(&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++ = '\0'; 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 #ifdef MACHINE_STACK_GROWS_UP 392 sgap = ALIGN(sgap); 393 #endif 394 /* Now check if args & environ fit into new stack */ 395 len = ((argc + envc + 2 + pack.ep_emul->e_arglen) * sizeof(char *) + 396 sizeof(long) + dp + sgap + sizeof(struct ps_strings)) - argp; 397 398 len = ALIGN(len); /* make the stack "safely" aligned */ 399 400 if (len > pack.ep_ssize) { /* in effect, compare to initial limit */ 401 error = ENOMEM; 402 goto bad; 403 } 404 405 /* adjust "active stack depth" for process VSZ */ 406 pack.ep_ssize = len; /* maybe should go elsewhere, but... */ 407 408 /* 409 * Prepare vmspace for remapping. Note that uvmspace_exec can replace 410 * p_vmspace! 411 */ 412 uvmspace_exec(p, VM_MIN_ADDRESS, VM_MAXUSER_ADDRESS); 413 414 vm = p->p_vmspace; 415 /* Now map address space */ 416 vm->vm_taddr = (char *)pack.ep_taddr; 417 vm->vm_tsize = atop(round_page(pack.ep_tsize)); 418 vm->vm_daddr = (char *)pack.ep_daddr; 419 vm->vm_dsize = atop(round_page(pack.ep_dsize)); 420 vm->vm_dused = 0; 421 vm->vm_ssize = atop(round_page(pack.ep_ssize)); 422 vm->vm_maxsaddr = (char *)pack.ep_maxsaddr; 423 vm->vm_minsaddr = (char *)pack.ep_minsaddr; 424 425 /* create the new process's VM space by running the vmcmds */ 426 #ifdef DIAGNOSTIC 427 if (pack.ep_vmcmds.evs_used == 0) 428 panic("execve: no vmcmds"); 429 #endif 430 error = exec_process_vmcmds(p, &pack); 431 432 /* if an error happened, deallocate and punt */ 433 if (error) 434 goto exec_abort; 435 436 /* remember information about the process */ 437 arginfo.ps_nargvstr = argc; 438 arginfo.ps_nenvstr = envc; 439 440 #ifdef MACHINE_STACK_GROWS_UP 441 stack = (char *)USRSTACK + sizeof(arginfo) + sgap; 442 slen = len - sizeof(arginfo) - sgap; 443 #else 444 stack = (char *)(USRSTACK - len); 445 #endif 446 /* Now copy argc, args & environ to new stack */ 447 if (!(*pack.ep_emul->e_copyargs)(&pack, &arginfo, stack, argp)) 448 goto exec_abort; 449 450 /* copy out the process's ps_strings structure */ 451 if (copyout(&arginfo, (char *)PS_STRINGS, sizeof(arginfo))) 452 goto exec_abort; 453 454 stopprofclock(p); /* stop profiling */ 455 fdcloseexec(p); /* handle close on exec */ 456 execsigs(p); /* reset caught signals */ 457 458 /* set command name & other accounting info */ 459 len = min(nid.ni_cnd.cn_namelen, MAXCOMLEN); 460 bcopy(nid.ni_cnd.cn_nameptr, p->p_comm, len); 461 p->p_comm[len] = 0; 462 p->p_acflag &= ~AFORK; 463 464 /* record proc's vnode, for use by procfs and others */ 465 if (p->p_textvp) 466 vrele(p->p_textvp); 467 VREF(pack.ep_vp); 468 p->p_textvp = pack.ep_vp; 469 470 atomic_setbits_int(&p->p_flag, P_EXEC); 471 if (p->p_flag & P_PPWAIT) { 472 atomic_clearbits_int(&p->p_flag, P_PPWAIT); 473 wakeup((caddr_t)p->p_pptr); 474 } 475 476 /* 477 * If process does execve() while it has a mismatched real, 478 * effective, or saved uid/gid, we set P_SUGIDEXEC. 479 */ 480 if (p->p_ucred->cr_uid != p->p_cred->p_ruid || 481 p->p_ucred->cr_uid != p->p_cred->p_svuid || 482 p->p_ucred->cr_gid != p->p_cred->p_rgid || 483 p->p_ucred->cr_gid != p->p_cred->p_svgid) 484 atomic_setbits_int(&p->p_flag, P_SUGIDEXEC); 485 else 486 atomic_clearbits_int(&p->p_flag, P_SUGIDEXEC); 487 488 /* 489 * deal with set[ug]id. 490 * MNT_NOEXEC has already been used to disable s[ug]id. 491 */ 492 if ((attr.va_mode & (VSUID | VSGID)) && proc_cansugid(p)) { 493 int i; 494 495 atomic_setbits_int(&p->p_flag, P_SUGID|P_SUGIDEXEC); 496 497 #ifdef KTRACE 498 /* 499 * If process is being ktraced, turn off - unless 500 * root set it. 501 */ 502 if (p->p_tracep && !(p->p_traceflag & KTRFAC_ROOT)) { 503 p->p_traceflag = 0; 504 ktrsettracevnode(p, NULL); 505 } 506 #endif 507 p->p_ucred = crcopy(cred); 508 if (attr.va_mode & VSUID) 509 p->p_ucred->cr_uid = attr.va_uid; 510 if (attr.va_mode & VSGID) 511 p->p_ucred->cr_gid = attr.va_gid; 512 513 /* 514 * For set[ug]id processes, a few caveats apply to 515 * stdin, stdout, and stderr. 516 */ 517 for (i = 0; i < 3; i++) { 518 struct file *fp = NULL; 519 520 /* 521 * NOTE - This will never return NULL because of 522 * immature fds. The file descriptor table is not 523 * shared because we're suid. 524 */ 525 fp = fd_getfile(p->p_fd, i); 526 #ifdef PROCFS 527 /* 528 * Close descriptors that are writing to procfs. 529 */ 530 if (fp && fp->f_type == DTYPE_VNODE && 531 ((struct vnode *)(fp->f_data))->v_tag == VT_PROCFS && 532 (fp->f_flag & FWRITE)) { 533 fdrelease(p, i); 534 fp = NULL; 535 } 536 #endif 537 538 /* 539 * Ensure that stdin, stdout, and stderr are already 540 * allocated. We do not want userland to accidentally 541 * allocate descriptors in this range which has implied 542 * meaning to libc. 543 */ 544 if (fp == NULL) { 545 short flags = FREAD | (i == 0 ? 0 : FWRITE); 546 struct vnode *vp; 547 int indx; 548 549 if ((error = falloc(p, &fp, &indx)) != 0) 550 goto exec_abort; 551 #ifdef DIAGNOSTIC 552 if (indx != i) 553 panic("sys_execve: falloc indx != i"); 554 #endif 555 if ((error = cdevvp(getnulldev(), &vp)) != 0) { 556 fdremove(p->p_fd, indx); 557 closef(fp, p); 558 goto exec_abort; 559 } 560 if ((error = VOP_OPEN(vp, flags, p->p_ucred, p)) != 0) { 561 fdremove(p->p_fd, indx); 562 closef(fp, p); 563 vrele(vp); 564 goto exec_abort; 565 } 566 if (flags & FWRITE) 567 vp->v_writecount++; 568 fp->f_flag = flags; 569 fp->f_type = DTYPE_VNODE; 570 fp->f_ops = &vnops; 571 fp->f_data = (caddr_t)vp; 572 FILE_SET_MATURE(fp); 573 } 574 } 575 } else 576 atomic_clearbits_int(&p->p_flag, P_SUGID); 577 p->p_cred->p_svuid = p->p_ucred->cr_uid; 578 p->p_cred->p_svgid = p->p_ucred->cr_gid; 579 580 if (p->p_flag & P_SUGIDEXEC) { 581 int i, s = splclock(); 582 583 timeout_del(&p->p_realit_to); 584 timerclear(&p->p_realtimer.it_interval); 585 timerclear(&p->p_realtimer.it_value); 586 for (i = 0; i < sizeof(p->p_stats->p_timer) / 587 sizeof(p->p_stats->p_timer[0]); i++) { 588 timerclear(&p->p_stats->p_timer[i].it_interval); 589 timerclear(&p->p_stats->p_timer[i].it_value); 590 } 591 splx(s); 592 } 593 594 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 595 596 pool_put(&namei_pool, nid.ni_cnd.cn_pnbuf); 597 vn_close(pack.ep_vp, FREAD, cred, p); 598 599 /* 600 * notify others that we exec'd 601 */ 602 KNOTE(&p->p_klist, NOTE_EXEC); 603 604 /* setup new registers and do misc. setup. */ 605 if (pack.ep_emul->e_fixup != NULL) { 606 if ((*pack.ep_emul->e_fixup)(p, &pack) != 0) 607 goto free_pack_abort; 608 } 609 #ifdef MACHINE_STACK_GROWS_UP 610 (*pack.ep_emul->e_setregs)(p, &pack, (u_long)stack + slen, retval); 611 #else 612 (*pack.ep_emul->e_setregs)(p, &pack, (u_long)stack, retval); 613 #endif 614 615 /* map the process's signal trampoline code */ 616 if (exec_sigcode_map(p, pack.ep_emul)) 617 goto free_pack_abort; 618 619 if (p->p_flag & P_TRACED) 620 psignal(p, SIGTRAP); 621 622 free(pack.ep_hdr, M_EXEC); 623 624 /* 625 * Call emulation specific exec hook. This can setup per-process 626 * p->p_emuldata or do any other per-process stuff an emulation needs. 627 * 628 * If we are executing process of different emulation than the 629 * original forked process, call e_proc_exit() of the old emulation 630 * first, then e_proc_exec() of new emulation. If the emulation is 631 * same, the exec hook code should deallocate any old emulation 632 * resources held previously by this process. 633 */ 634 if (p->p_emul && p->p_emul->e_proc_exit && 635 p->p_emul != pack.ep_emul) 636 (*p->p_emul->e_proc_exit)(p); 637 638 p->p_descfd = 255; 639 if ((pack.ep_flags & EXEC_HASFD) && pack.ep_fd < 255) 640 p->p_descfd = pack.ep_fd; 641 642 /* 643 * Call exec hook. Emulation code may NOT store reference to anything 644 * from &pack. 645 */ 646 if (pack.ep_emul->e_proc_exec) 647 (*pack.ep_emul->e_proc_exec)(p, &pack); 648 649 /* update p_emul, the old value is no longer needed */ 650 p->p_emul = pack.ep_emul; 651 652 #ifdef KTRACE 653 if (KTRPOINT(p, KTR_EMUL)) 654 ktremul(p, p->p_emul->e_name); 655 #endif 656 657 atomic_clearbits_int(&p->p_flag, P_INEXEC); 658 659 #if NSYSTRACE > 0 660 if (ISSET(p->p_flag, P_SYSTRACE) && 661 wassugid && !ISSET(p->p_flag, P_SUGID) && 662 !ISSET(p->p_flag, P_SUGIDEXEC)) 663 systrace_execve1(pathbuf, p); 664 #endif 665 666 if (pathbuf != NULL) 667 pool_put(&namei_pool, pathbuf); 668 669 return (0); 670 671 bad: 672 /* free the vmspace-creation commands, and release their references */ 673 kill_vmcmds(&pack.ep_vmcmds); 674 /* kill any opened file descriptor, if necessary */ 675 if (pack.ep_flags & EXEC_HASFD) { 676 pack.ep_flags &= ~EXEC_HASFD; 677 (void) fdrelease(p, pack.ep_fd); 678 } 679 if (pack.ep_interp != NULL) 680 pool_put(&namei_pool, pack.ep_interp); 681 if (pack.ep_emul_arg != NULL) 682 free(pack.ep_emul_arg, M_TEMP); 683 /* close and put the exec'd file */ 684 vn_close(pack.ep_vp, FREAD, cred, p); 685 pool_put(&namei_pool, nid.ni_cnd.cn_pnbuf); 686 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 687 688 freehdr: 689 free(pack.ep_hdr, M_EXEC); 690 #if NSYSTRACE > 0 691 clrflag: 692 #endif 693 atomic_clearbits_int(&p->p_flag, P_INEXEC); 694 695 if (pathbuf != NULL) 696 pool_put(&namei_pool, pathbuf); 697 698 return (error); 699 700 exec_abort: 701 /* 702 * the old process doesn't exist anymore. exit gracefully. 703 * get rid of the (new) address space we have created, if any, get rid 704 * of our namei data and vnode, and exit noting failure 705 */ 706 uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, 707 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); 708 if (pack.ep_interp != NULL) 709 pool_put(&namei_pool, pack.ep_interp); 710 if (pack.ep_emul_arg != NULL) 711 free(pack.ep_emul_arg, M_TEMP); 712 pool_put(&namei_pool, nid.ni_cnd.cn_pnbuf); 713 vn_close(pack.ep_vp, FREAD, cred, p); 714 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 715 716 free_pack_abort: 717 free(pack.ep_hdr, M_EXEC); 718 exit1(p, W_EXITCODE(0, SIGABRT), EXIT_NORMAL); 719 720 /* NOTREACHED */ 721 atomic_clearbits_int(&p->p_flag, P_INEXEC); 722 if (pathbuf != NULL) 723 pool_put(&namei_pool, pathbuf); 724 725 return (0); 726 } 727 728 729 void * 730 copyargs(struct exec_package *pack, struct ps_strings *arginfo, void *stack, 731 void *argp) 732 { 733 char **cpp = stack; 734 char *dp, *sp; 735 size_t len; 736 void *nullp = NULL; 737 long argc = arginfo->ps_nargvstr; 738 int envc = arginfo->ps_nenvstr; 739 740 if (copyout(&argc, cpp++, sizeof(argc))) 741 return (NULL); 742 743 dp = (char *) (cpp + argc + envc + 2 + pack->ep_emul->e_arglen); 744 sp = argp; 745 746 /* XXX don't copy them out, remap them! */ 747 arginfo->ps_argvstr = cpp; /* remember location of argv for later */ 748 749 for (; --argc >= 0; sp += len, dp += len) 750 if (copyout(&dp, cpp++, sizeof(dp)) || 751 copyoutstr(sp, dp, ARG_MAX, &len)) 752 return (NULL); 753 754 if (copyout(&nullp, cpp++, sizeof(nullp))) 755 return (NULL); 756 757 arginfo->ps_envstr = cpp; /* remember location of envp for later */ 758 759 for (; --envc >= 0; sp += len, dp += len) 760 if (copyout(&dp, cpp++, sizeof(dp)) || 761 copyoutstr(sp, dp, ARG_MAX, &len)) 762 return (NULL); 763 764 if (copyout(&nullp, cpp++, sizeof(nullp))) 765 return (NULL); 766 767 return (cpp); 768 } 769 770 int 771 exec_sigcode_map(struct proc *p, struct emul *e) 772 { 773 vsize_t sz; 774 775 sz = (vaddr_t)e->e_esigcode - (vaddr_t)e->e_sigcode; 776 777 /* 778 * If we don't have a sigobject for this emulation, create one. 779 * 780 * sigobject is an anonymous memory object (just like SYSV shared 781 * memory) that we keep a permanent reference to and that we map 782 * in all processes that need this sigcode. The creation is simple, 783 * we create an object, add a permanent reference to it, map it in 784 * kernel space, copy out the sigcode to it and unmap it. 785 * Then we map it with PROT_READ|PROT_EXEC into the process just 786 * the way sys_mmap would map it. 787 */ 788 if (e->e_sigobject == NULL) { 789 vaddr_t va; 790 int r; 791 792 e->e_sigobject = uao_create(sz, 0); 793 uao_reference(e->e_sigobject); /* permanent reference */ 794 795 va = vm_map_min(kernel_map); /* hint */ 796 if ((r = uvm_map(kernel_map, &va, round_page(sz), e->e_sigobject, 797 0, 0, UVM_MAPFLAG(UVM_PROT_RW, UVM_PROT_RW, 798 UVM_INH_SHARE, UVM_ADV_RANDOM, 0)))) { 799 uao_detach(e->e_sigobject); 800 return (ENOMEM); 801 } 802 memcpy((void *)va, e->e_sigcode, sz); 803 uvm_unmap(kernel_map, va, va + round_page(sz)); 804 } 805 806 /* Just a hint to uvm_mmap where to put it. */ 807 p->p_sigcode = uvm_map_hint(p, VM_PROT_READ|VM_PROT_EXECUTE); 808 uao_reference(e->e_sigobject); 809 if (uvm_map(&p->p_vmspace->vm_map, &p->p_sigcode, round_page(sz), 810 e->e_sigobject, 0, 0, UVM_MAPFLAG(UVM_PROT_RX, UVM_PROT_RX, 811 UVM_INH_SHARE, UVM_ADV_RANDOM, 0))) { 812 uao_detach(e->e_sigobject); 813 return (ENOMEM); 814 } 815 816 return (0); 817 } 818