1 /* $OpenBSD: kern_exec.c,v 1.90 2004/08/24 23:01:26 mickey 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 = 64*1024; 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(p, epp) 113 struct proc *p; 114 struct exec_package *epp; 115 { 116 int error, i; 117 struct vnode *vp; 118 struct nameidata *ndp; 119 size_t resid; 120 121 ndp = epp->ep_ndp; 122 ndp->ni_cnd.cn_nameiop = LOOKUP; 123 ndp->ni_cnd.cn_flags = FOLLOW | LOCKLEAF | SAVENAME; 124 /* first get the vnode */ 125 if ((error = namei(ndp)) != 0) 126 return (error); 127 epp->ep_vp = vp = ndp->ni_vp; 128 129 /* check for regular file */ 130 if (vp->v_type == VDIR) { 131 error = EISDIR; 132 goto bad1; 133 } 134 if (vp->v_type != VREG) { 135 error = EACCES; 136 goto bad1; 137 } 138 139 /* get attributes */ 140 if ((error = VOP_GETATTR(vp, epp->ep_vap, p->p_ucred, p)) != 0) 141 goto bad1; 142 143 /* Check mount point */ 144 if (vp->v_mount->mnt_flag & MNT_NOEXEC) { 145 error = EACCES; 146 goto bad1; 147 } 148 149 if ((vp->v_mount->mnt_flag & MNT_NOSUID)) 150 epp->ep_vap->va_mode &= ~(VSUID | VSGID); 151 152 /* check access. for root we have to see if any exec bit on */ 153 if ((error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p)) != 0) 154 goto bad1; 155 if ((epp->ep_vap->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0) { 156 error = EACCES; 157 goto bad1; 158 } 159 160 /* try to open it */ 161 if ((error = VOP_OPEN(vp, FREAD, p->p_ucred, p)) != 0) 162 goto bad1; 163 164 /* unlock vp, we need it unlocked from here */ 165 VOP_UNLOCK(vp, 0, p); 166 167 /* now we have the file, get the exec header */ 168 error = vn_rdwr(UIO_READ, vp, epp->ep_hdr, epp->ep_hdrlen, 0, 169 UIO_SYSSPACE, 0, p->p_ucred, &resid, p); 170 if (error) 171 goto bad2; 172 epp->ep_hdrvalid = epp->ep_hdrlen - resid; 173 174 /* 175 * set up the vmcmds for creation of the process 176 * address space 177 */ 178 error = ENOEXEC; 179 for (i = 0; i < nexecs && error != 0; i++) { 180 int newerror; 181 182 if (execsw[i].es_check == NULL) 183 continue; 184 newerror = (*execsw[i].es_check)(p, epp); 185 if (!newerror && !(epp->ep_emul->e_flags & EMUL_ENABLED)) 186 newerror = ENOEXEC; 187 /* make sure the first "interesting" error code is saved. */ 188 if (!newerror || error == ENOEXEC) 189 error = newerror; 190 if (epp->ep_flags & EXEC_DESTR && error != 0) 191 return (error); 192 } 193 if (!error) { 194 /* check that entry point is sane */ 195 if (epp->ep_entry > VM_MAXUSER_ADDRESS) { 196 error = ENOEXEC; 197 } 198 199 /* check limits */ 200 if ((epp->ep_tsize > MAXTSIZ) || 201 (epp->ep_dsize > p->p_rlimit[RLIMIT_DATA].rlim_cur)) 202 error = ENOMEM; 203 204 if (!error) 205 return (0); 206 } 207 208 /* 209 * free any vmspace-creation commands, 210 * and release their references 211 */ 212 kill_vmcmds(&epp->ep_vmcmds); 213 214 bad2: 215 /* 216 * close the vnode, free the pathname buf, and punt. 217 */ 218 vn_close(vp, FREAD, p->p_ucred, p); 219 pool_put(&namei_pool, ndp->ni_cnd.cn_pnbuf); 220 return (error); 221 222 bad1: 223 /* 224 * free the namei pathname buffer, and put the vnode 225 * (which we don't yet have open). 226 */ 227 pool_put(&namei_pool, ndp->ni_cnd.cn_pnbuf); 228 vput(vp); 229 return (error); 230 } 231 232 /* 233 * exec system call 234 */ 235 /* ARGSUSED */ 236 int 237 sys_execve(p, v, retval) 238 register struct proc *p; 239 void *v; 240 register_t *retval; 241 { 242 struct sys_execve_args /* { 243 syscallarg(const char *) path; 244 syscallarg(char *const *) argp; 245 syscallarg(char *const *) envp; 246 } */ *uap = v; 247 int error; 248 struct exec_package pack; 249 struct nameidata nid; 250 struct vattr attr; 251 struct ucred *cred = p->p_ucred; 252 char *argp; 253 char * const *cpp, *dp, *sp; 254 long argc, envc; 255 size_t len, sgap; 256 #ifdef MACHINE_STACK_GROWS_UP 257 size_t slen; 258 #endif 259 char *stack; 260 struct ps_strings arginfo; 261 struct vmspace *vm = p->p_vmspace; 262 char **tmpfap; 263 extern struct emul emul_native; 264 #if NSYSTRACE > 0 265 int wassugid = 266 ISSET(p->p_flag, P_SUGID) || ISSET(p->p_flag, P_SUGIDEXEC); 267 char pathbuf[MAXPATHLEN]; 268 size_t pathbuflen; 269 #endif 270 271 /* 272 * Cheap solution to complicated problems. 273 * Mark this process as "leave me alone, I'm execing". 274 */ 275 p->p_flag |= P_INEXEC; 276 277 #if NSYSTRACE > 0 278 if (ISSET(p->p_flag, P_SYSTRACE)) 279 systrace_execve0(p); 280 281 error = copyinstr(SCARG(uap, path), pathbuf, MAXPATHLEN, &pathbuflen); 282 if (error != 0) 283 goto clrflag; 284 285 NDINIT(&nid, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, p); 286 #else 287 /* init the namei data to point the file user's program name */ 288 NDINIT(&nid, LOOKUP, NOFOLLOW, UIO_USERSPACE, SCARG(uap, path), p); 289 #endif 290 291 /* 292 * initialize the fields of the exec package. 293 */ 294 #if NSYSTRACE > 0 295 pack.ep_name = pathbuf; 296 #else 297 pack.ep_name = (char *)SCARG(uap, path); 298 #endif 299 pack.ep_hdr = malloc(exec_maxhdrsz, M_EXEC, M_WAITOK); 300 pack.ep_hdrlen = exec_maxhdrsz; 301 pack.ep_hdrvalid = 0; 302 pack.ep_ndp = &nid; 303 pack.ep_interp = NULL; 304 pack.ep_emul_arg = NULL; 305 VMCMDSET_INIT(&pack.ep_vmcmds); 306 pack.ep_vap = &attr; 307 pack.ep_emul = &emul_native; 308 pack.ep_flags = 0; 309 310 /* see if we can run it. */ 311 if ((error = check_exec(p, &pack)) != 0) { 312 goto freehdr; 313 } 314 315 /* XXX -- THE FOLLOWING SECTION NEEDS MAJOR CLEANUP */ 316 317 /* allocate an argument buffer */ 318 argp = (char *) uvm_km_valloc_wait(exec_map, NCARGS); 319 #ifdef DIAGNOSTIC 320 if (argp == NULL) 321 panic("execve: argp == NULL"); 322 #endif 323 dp = argp; 324 argc = 0; 325 326 /* copy the fake args list, if there's one, freeing it as we go */ 327 if (pack.ep_flags & EXEC_HASARGL) { 328 tmpfap = pack.ep_fa; 329 while (*tmpfap != NULL) { 330 char *cp; 331 332 cp = *tmpfap; 333 while (*cp) 334 *dp++ = *cp++; 335 dp++; 336 337 free(*tmpfap, M_EXEC); 338 tmpfap++; argc++; 339 } 340 FREE(pack.ep_fa, M_EXEC); 341 pack.ep_flags &= ~EXEC_HASARGL; 342 } 343 344 /* Now get argv & environment */ 345 if (!(cpp = SCARG(uap, argp))) { 346 error = EFAULT; 347 goto bad; 348 } 349 350 if (pack.ep_flags & EXEC_SKIPARG) 351 cpp++; 352 353 while (1) { 354 len = argp + ARG_MAX - dp; 355 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0) 356 goto bad; 357 if (!sp) 358 break; 359 if ((error = copyinstr(sp, dp, len, &len)) != 0) { 360 if (error == ENAMETOOLONG) 361 error = E2BIG; 362 goto bad; 363 } 364 dp += len; 365 cpp++; 366 argc++; 367 } 368 369 envc = 0; 370 /* environment does not need to be there */ 371 if ((cpp = SCARG(uap, envp)) != NULL ) { 372 while (1) { 373 len = argp + ARG_MAX - dp; 374 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0) 375 goto bad; 376 if (!sp) 377 break; 378 if ((error = copyinstr(sp, dp, len, &len)) != 0) { 379 if (error == ENAMETOOLONG) 380 error = E2BIG; 381 goto bad; 382 } 383 dp += len; 384 cpp++; 385 envc++; 386 } 387 } 388 389 dp = (char *)ALIGN(dp); 390 391 sgap = STACKGAPLEN; 392 if (stackgap_random != 0) 393 sgap += (arc4random() * ALIGNBYTES) & (stackgap_random - 1); 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 = btoc(pack.ep_tsize); 418 vm->vm_daddr = (char *)pack.ep_daddr; 419 vm->vm_dsize = btoc(pack.ep_dsize); 420 vm->vm_ssize = btoc(pack.ep_ssize); 421 vm->vm_maxsaddr = (char *)pack.ep_maxsaddr; 422 vm->vm_minsaddr = (char *)pack.ep_minsaddr; 423 424 /* create the new process's VM space by running the vmcmds */ 425 #ifdef DIAGNOSTIC 426 if (pack.ep_vmcmds.evs_used == 0) 427 panic("execve: no vmcmds"); 428 #endif 429 error = exec_process_vmcmds(p, &pack); 430 431 /* if an error happened, deallocate and punt */ 432 if (error) 433 goto exec_abort; 434 435 /* remember information about the process */ 436 arginfo.ps_nargvstr = argc; 437 arginfo.ps_nenvstr = envc; 438 439 #ifdef MACHINE_STACK_GROWS_UP 440 stack = (char *)USRSTACK + sizeof(arginfo); 441 slen = len - sizeof(arginfo); 442 #else 443 stack = (char *)(USRSTACK - len); 444 #endif 445 /* Now copy argc, args & environ to new stack */ 446 if (!(*pack.ep_emul->e_copyargs)(&pack, &arginfo, stack, argp)) 447 goto exec_abort; 448 449 /* copy out the process's ps_strings structure */ 450 if (copyout(&arginfo, (char *)PS_STRINGS, sizeof(arginfo))) 451 goto exec_abort; 452 453 stopprofclock(p); /* stop profiling */ 454 fdcloseexec(p); /* handle close on exec */ 455 execsigs(p); /* reset catched signals */ 456 457 /* set command name & other accounting info */ 458 len = min(nid.ni_cnd.cn_namelen, MAXCOMLEN); 459 bcopy(nid.ni_cnd.cn_nameptr, p->p_comm, len); 460 p->p_comm[len] = 0; 461 p->p_acflag &= ~AFORK; 462 463 /* record proc's vnode, for use by procfs and others */ 464 if (p->p_textvp) 465 vrele(p->p_textvp); 466 VREF(pack.ep_vp); 467 p->p_textvp = pack.ep_vp; 468 469 p->p_flag |= P_EXEC; 470 if (p->p_flag & P_PPWAIT) { 471 p->p_flag &= ~P_PPWAIT; 472 wakeup((caddr_t)p->p_pptr); 473 } 474 475 /* 476 * If process does execve() while it has a mismatched real, 477 * effective, or saved uid/gid, we set P_SUGIDEXEC. 478 */ 479 if (p->p_ucred->cr_uid != p->p_cred->p_ruid || 480 p->p_ucred->cr_uid != p->p_cred->p_svuid || 481 p->p_ucred->cr_gid != p->p_cred->p_rgid || 482 p->p_ucred->cr_gid != p->p_cred->p_svgid) 483 p->p_flag |= P_SUGIDEXEC; 484 else 485 p->p_flag &= ~P_SUGIDEXEC; 486 487 /* 488 * deal with set[ug]id. 489 * MNT_NOEXEC has already been used to disable s[ug]id. 490 */ 491 if ((attr.va_mode & (VSUID | VSGID)) && proc_cansugid(p)) { 492 int i; 493 494 p->p_flag |= P_SUGID; 495 p->p_flag |= 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 * unmature 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 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 /* 639 * Call exec hook. Emulation code may NOT store reference to anything 640 * from &pack. 641 */ 642 if (pack.ep_emul->e_proc_exec) 643 (*pack.ep_emul->e_proc_exec)(p, &pack); 644 645 /* update p_emul, the old value is no longer needed */ 646 p->p_emul = pack.ep_emul; 647 648 #ifdef KTRACE 649 if (KTRPOINT(p, KTR_EMUL)) 650 ktremul(p, p->p_emul->e_name); 651 #endif 652 653 p->p_flag &= ~P_INEXEC; 654 655 #if NSYSTRACE > 0 656 if (ISSET(p->p_flag, P_SYSTRACE) && 657 wassugid && !ISSET(p->p_flag, P_SUGID) && 658 !ISSET(p->p_flag, P_SUGIDEXEC)) 659 systrace_execve1(pathbuf, p); 660 #endif 661 662 return (0); 663 664 bad: 665 /* free the vmspace-creation commands, and release their references */ 666 kill_vmcmds(&pack.ep_vmcmds); 667 /* kill any opened file descriptor, if necessary */ 668 if (pack.ep_flags & EXEC_HASFD) { 669 pack.ep_flags &= ~EXEC_HASFD; 670 (void) fdrelease(p, pack.ep_fd); 671 } 672 if (pack.ep_interp != NULL) 673 FREE(pack.ep_interp, M_TEMP); 674 if (pack.ep_emul_arg != NULL) 675 FREE(pack.ep_emul_arg, M_TEMP); 676 /* close and put the exec'd file */ 677 vn_close(pack.ep_vp, FREAD, cred, p); 678 pool_put(&namei_pool, nid.ni_cnd.cn_pnbuf); 679 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 680 681 freehdr: 682 free(pack.ep_hdr, M_EXEC); 683 #if NSYSTRACE > 0 684 clrflag: 685 #endif 686 p->p_flag &= ~P_INEXEC; 687 return (error); 688 689 exec_abort: 690 /* 691 * the old process doesn't exist anymore. exit gracefully. 692 * get rid of the (new) address space we have created, if any, get rid 693 * of our namei data and vnode, and exit noting failure 694 */ 695 uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, 696 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); 697 if (pack.ep_interp != NULL) 698 FREE(pack.ep_interp, M_TEMP); 699 if (pack.ep_emul_arg != NULL) 700 FREE(pack.ep_emul_arg, M_TEMP); 701 pool_put(&namei_pool, nid.ni_cnd.cn_pnbuf); 702 vn_close(pack.ep_vp, FREAD, cred, p); 703 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 704 705 free_pack_abort: 706 free(pack.ep_hdr, M_EXEC); 707 exit1(p, W_EXITCODE(0, SIGABRT)); 708 709 /* NOTREACHED */ 710 p->p_flag &= ~P_INEXEC; 711 return (0); 712 } 713 714 715 void * 716 copyargs(pack, arginfo, stack, argp) 717 struct exec_package *pack; 718 struct ps_strings *arginfo; 719 void *stack; 720 void *argp; 721 { 722 char **cpp = stack; 723 char *dp, *sp; 724 size_t len; 725 void *nullp = NULL; 726 long argc = arginfo->ps_nargvstr; 727 int envc = arginfo->ps_nenvstr; 728 729 if (copyout(&argc, cpp++, sizeof(argc))) 730 return (NULL); 731 732 dp = (char *) (cpp + argc + envc + 2 + pack->ep_emul->e_arglen); 733 sp = argp; 734 735 /* XXX don't copy them out, remap them! */ 736 arginfo->ps_argvstr = cpp; /* remember location of argv for later */ 737 738 for (; --argc >= 0; sp += len, dp += len) 739 if (copyout(&dp, cpp++, sizeof(dp)) || 740 copyoutstr(sp, dp, ARG_MAX, &len)) 741 return (NULL); 742 743 if (copyout(&nullp, cpp++, sizeof(nullp))) 744 return (NULL); 745 746 arginfo->ps_envstr = cpp; /* remember location of envp for later */ 747 748 for (; --envc >= 0; sp += len, dp += len) 749 if (copyout(&dp, cpp++, sizeof(dp)) || 750 copyoutstr(sp, dp, ARG_MAX, &len)) 751 return (NULL); 752 753 if (copyout(&nullp, cpp++, sizeof(nullp))) 754 return (NULL); 755 756 return (cpp); 757 } 758 759 int 760 exec_sigcode_map(struct proc *p, struct emul *e) 761 { 762 vsize_t sz; 763 764 sz = (vaddr_t)e->e_esigcode - (vaddr_t)e->e_sigcode; 765 766 /* 767 * If we don't have a sigobject for this emulation, create one. 768 * 769 * sigobject is an anonymous memory object (just like SYSV shared 770 * memory) that we keep a permanent reference to and that we map 771 * in all processes that need this sigcode. The creation is simple, 772 * we create an object, add a permanent reference to it, map it in 773 * kernel space, copy out the sigcode to it and unmap it. 774 * Then we map it with PROT_READ|PROT_EXEC into the process just 775 * the way sys_mmap would map it. 776 */ 777 if (e->e_sigobject == NULL) { 778 vaddr_t va; 779 int r; 780 781 e->e_sigobject = uao_create(sz, 0); 782 uao_reference(e->e_sigobject); /* permanent reference */ 783 784 va = vm_map_min(kernel_map); /* hint */ 785 if ((r = uvm_map(kernel_map, &va, round_page(sz), e->e_sigobject, 786 0, 0, UVM_MAPFLAG(UVM_PROT_RW, UVM_PROT_RW, 787 UVM_INH_SHARE, UVM_ADV_RANDOM, 0)))) { 788 printf("kernel mapping failed %d\n", r); 789 uao_detach(e->e_sigobject); 790 return (ENOMEM); 791 } 792 memcpy((void *)va, e->e_sigcode, sz); 793 uvm_unmap(kernel_map, va, va + round_page(sz)); 794 } 795 796 /* Just a hint to uvm_mmap where to put it. */ 797 p->p_sigcode = uvm_map_hint(p, VM_PROT_READ|VM_PROT_EXECUTE); 798 uao_reference(e->e_sigobject); 799 if (uvm_map(&p->p_vmspace->vm_map, &p->p_sigcode, round_page(sz), 800 e->e_sigobject, 0, 0, UVM_MAPFLAG(UVM_PROT_RX, UVM_PROT_RX, 801 UVM_INH_SHARE, UVM_ADV_RANDOM, 0))) { 802 printf("user mapping failed\n"); 803 uao_detach(e->e_sigobject); 804 return (ENOMEM); 805 } 806 807 return (0); 808 } 809