1 /* $OpenBSD: kern_exec.c,v 1.193 2018/01/02 06:38:45 guenther 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/fcntl.h> 47 #include <sys/file.h> 48 #include <sys/acct.h> 49 #include <sys/exec.h> 50 #include <sys/ktrace.h> 51 #include <sys/resourcevar.h> 52 #include <sys/wait.h> 53 #include <sys/mman.h> 54 #include <sys/signalvar.h> 55 #include <sys/stat.h> 56 #include <sys/conf.h> 57 #include <sys/pledge.h> 58 #ifdef SYSVSHM 59 #include <sys/shm.h> 60 #endif 61 62 #include <sys/syscallargs.h> 63 64 #include <uvm/uvm_extern.h> 65 #include <machine/tcb.h> 66 67 const struct kmem_va_mode kv_exec = { 68 .kv_wait = 1, 69 .kv_map = &exec_map 70 }; 71 72 /* 73 * Map the shared signal code. 74 */ 75 int exec_sigcode_map(struct process *, struct emul *); 76 77 /* 78 * If non-zero, stackgap_random specifies the upper limit of the random gap size 79 * added to the fixed stack position. Must be n^2. 80 */ 81 int stackgap_random = STACKGAP_RANDOM; 82 83 /* 84 * check exec: 85 * given an "executable" described in the exec package's namei info, 86 * see what we can do with it. 87 * 88 * ON ENTRY: 89 * exec package with appropriate namei info 90 * proc pointer of exec'ing proc 91 * NO SELF-LOCKED VNODES 92 * 93 * ON EXIT: 94 * error: nothing held, etc. exec header still allocated. 95 * ok: filled exec package, one locked vnode. 96 * 97 * EXEC SWITCH ENTRY: 98 * Locked vnode to check, exec package, proc. 99 * 100 * EXEC SWITCH EXIT: 101 * ok: return 0, filled exec package, one locked vnode. 102 * error: destructive: 103 * everything deallocated except exec header. 104 * non-destructive: 105 * error code, locked vnode, exec header unmodified 106 */ 107 int 108 check_exec(struct proc *p, struct exec_package *epp) 109 { 110 int error, i; 111 struct vnode *vp; 112 struct nameidata *ndp; 113 size_t resid; 114 115 ndp = epp->ep_ndp; 116 ndp->ni_cnd.cn_nameiop = LOOKUP; 117 ndp->ni_cnd.cn_flags = FOLLOW | LOCKLEAF | SAVENAME; 118 /* first get the vnode */ 119 if ((error = namei(ndp)) != 0) 120 return (error); 121 epp->ep_vp = vp = ndp->ni_vp; 122 123 /* check for regular file */ 124 if (vp->v_type == VDIR) { 125 error = EISDIR; 126 goto bad1; 127 } 128 if (vp->v_type != VREG) { 129 error = EACCES; 130 goto bad1; 131 } 132 133 /* get attributes */ 134 if ((error = VOP_GETATTR(vp, epp->ep_vap, p->p_ucred, p)) != 0) 135 goto bad1; 136 137 /* Check mount point */ 138 if (vp->v_mount->mnt_flag & MNT_NOEXEC) { 139 error = EACCES; 140 goto bad1; 141 } 142 143 /* SUID programs may not be started with execpromises */ 144 if ((epp->ep_vap->va_mode & (VSUID | VSGID)) && 145 (p->p_p->ps_flags & PS_EXECPLEDGE)) { 146 error = EACCES; 147 goto bad1; 148 } 149 150 if ((vp->v_mount->mnt_flag & MNT_NOSUID)) 151 epp->ep_vap->va_mode &= ~(VSUID | VSGID); 152 153 /* check access. for root we have to see if any exec bit on */ 154 if ((error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p)) != 0) 155 goto bad1; 156 if ((epp->ep_vap->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0) { 157 error = EACCES; 158 goto bad1; 159 } 160 161 /* try to open it */ 162 if ((error = VOP_OPEN(vp, FREAD, p->p_ucred, p)) != 0) 163 goto bad1; 164 165 /* unlock vp, we need it unlocked from here */ 166 VOP_UNLOCK(vp, p); 167 168 /* now we have the file, get the exec header */ 169 error = vn_rdwr(UIO_READ, vp, epp->ep_hdr, epp->ep_hdrlen, 0, 170 UIO_SYSSPACE, 0, p->p_ucred, &resid, p); 171 if (error) 172 goto bad2; 173 epp->ep_hdrvalid = epp->ep_hdrlen - resid; 174 175 /* 176 * set up the vmcmds for creation of the process 177 * address space 178 */ 179 error = ENOEXEC; 180 for (i = 0; i < nexecs && error != 0; i++) { 181 int newerror; 182 183 if (execsw[i].es_check == NULL) 184 continue; 185 newerror = (*execsw[i].es_check)(p, epp); 186 if (!newerror && !(epp->ep_emul->e_flags & EMUL_ENABLED)) 187 newerror = EPERM; 188 /* make sure the first "interesting" error code is saved. */ 189 if (!newerror || error == ENOEXEC) 190 error = newerror; 191 if (epp->ep_flags & EXEC_DESTR && error != 0) 192 return (error); 193 } 194 if (!error) { 195 /* check that entry point is sane */ 196 if (epp->ep_entry > VM_MAXUSER_ADDRESS) { 197 error = ENOEXEC; 198 } 199 200 /* check limits */ 201 if ((epp->ep_tsize > MAXTSIZ) || 202 (epp->ep_dsize > p->p_rlimit[RLIMIT_DATA].rlim_cur)) 203 error = ENOMEM; 204 205 if (!error) 206 return (0); 207 } 208 209 /* 210 * free any vmspace-creation commands, 211 * and release their references 212 */ 213 kill_vmcmds(&epp->ep_vmcmds); 214 215 bad2: 216 /* 217 * close the vnode, free the pathname buf, and punt. 218 */ 219 vn_close(vp, FREAD, p->p_ucred, p); 220 pool_put(&namei_pool, ndp->ni_cnd.cn_pnbuf); 221 return (error); 222 223 bad1: 224 /* 225 * free the namei pathname buffer, and put the vnode 226 * (which we don't yet have open). 227 */ 228 pool_put(&namei_pool, ndp->ni_cnd.cn_pnbuf); 229 vput(vp); 230 return (error); 231 } 232 233 /* 234 * exec system call 235 */ 236 int 237 sys_execve(struct proc *p, void *v, register_t *retval) 238 { 239 struct sys_execve_args /* { 240 syscallarg(const char *) path; 241 syscallarg(char *const *) argp; 242 syscallarg(char *const *) envp; 243 } */ *uap = v; 244 int error; 245 struct exec_package pack; 246 struct nameidata nid; 247 struct vattr attr; 248 struct ucred *cred = p->p_ucred; 249 char *argp; 250 char * const *cpp, *dp, *sp; 251 #ifdef KTRACE 252 char *env_start; 253 #endif 254 struct process *pr = p->p_p; 255 long argc, envc; 256 size_t len, sgap, dstsize; 257 #ifdef MACHINE_STACK_GROWS_UP 258 size_t slen; 259 #endif 260 char *stack; 261 struct ps_strings arginfo; 262 struct vmspace *vm; 263 extern struct emul emul_native; 264 struct vnode *otvp; 265 266 /* get other threads to stop */ 267 if ((error = single_thread_set(p, SINGLE_UNWIND, 1))) 268 return (error); 269 270 /* 271 * Cheap solution to complicated problems. 272 * Mark this process as "leave me alone, I'm execing". 273 */ 274 atomic_setbits_int(&pr->ps_flags, PS_INEXEC); 275 276 NDINIT(&nid, LOOKUP, NOFOLLOW, UIO_USERSPACE, SCARG(uap, path), p); 277 nid.ni_pledge = PLEDGE_EXEC; 278 279 /* 280 * initialize the fields of the exec package. 281 */ 282 pack.ep_name = (char *)SCARG(uap, path); 283 pack.ep_hdr = malloc(exec_maxhdrsz, M_EXEC, M_WAITOK); 284 pack.ep_hdrlen = exec_maxhdrsz; 285 pack.ep_hdrvalid = 0; 286 pack.ep_ndp = &nid; 287 pack.ep_interp = NULL; 288 pack.ep_emul_arg = NULL; 289 VMCMDSET_INIT(&pack.ep_vmcmds); 290 pack.ep_vap = &attr; 291 pack.ep_emul = &emul_native; 292 pack.ep_flags = 0; 293 294 /* see if we can run it. */ 295 if ((error = check_exec(p, &pack)) != 0) { 296 goto freehdr; 297 } 298 299 /* XXX -- THE FOLLOWING SECTION NEEDS MAJOR CLEANUP */ 300 301 /* allocate an argument buffer */ 302 argp = km_alloc(NCARGS, &kv_exec, &kp_pageable, &kd_waitok); 303 #ifdef DIAGNOSTIC 304 if (argp == NULL) 305 panic("execve: argp == NULL"); 306 #endif 307 dp = argp; 308 argc = 0; 309 310 /* 311 * Copy the fake args list, if there's one, freeing it as we go. 312 * exec_script_makecmds() allocates either 2 or 3 fake args bounded 313 * by MAXINTERP + MAXPATHLEN < NCARGS so no overflow can happen. 314 */ 315 if (pack.ep_flags & EXEC_HASARGL) { 316 dstsize = NCARGS; 317 for(; pack.ep_fa[argc] != NULL; argc++) { 318 len = strlcpy(dp, pack.ep_fa[argc], dstsize); 319 len++; 320 dp += len; dstsize -= len; 321 if (pack.ep_fa[argc+1] != NULL) 322 free(pack.ep_fa[argc], M_EXEC, len); 323 else 324 free(pack.ep_fa[argc], M_EXEC, MAXPATHLEN); 325 } 326 free(pack.ep_fa, M_EXEC, 4 * sizeof(char *)); 327 pack.ep_flags &= ~EXEC_HASARGL; 328 } 329 330 /* Now get argv & environment */ 331 if (!(cpp = SCARG(uap, argp))) { 332 error = EFAULT; 333 goto bad; 334 } 335 336 if (pack.ep_flags & EXEC_SKIPARG) 337 cpp++; 338 339 while (1) { 340 len = argp + ARG_MAX - dp; 341 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0) 342 goto bad; 343 if (!sp) 344 break; 345 if ((error = copyinstr(sp, dp, len, &len)) != 0) { 346 if (error == ENAMETOOLONG) 347 error = E2BIG; 348 goto bad; 349 } 350 dp += len; 351 cpp++; 352 argc++; 353 } 354 355 /* must have at least one argument */ 356 if (argc == 0) { 357 error = EINVAL; 358 goto bad; 359 } 360 361 #ifdef KTRACE 362 if (KTRPOINT(p, KTR_EXECARGS)) 363 ktrexec(p, KTR_EXECARGS, argp, dp - argp); 364 #endif 365 366 envc = 0; 367 /* environment does not need to be there */ 368 if ((cpp = SCARG(uap, envp)) != NULL ) { 369 #ifdef KTRACE 370 env_start = dp; 371 #endif 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 #ifdef KTRACE 389 if (KTRPOINT(p, KTR_EXECENV)) 390 ktrexec(p, KTR_EXECENV, env_start, dp - env_start); 391 #endif 392 } 393 394 dp = (char *)(((long)dp + _STACKALIGNBYTES) & ~_STACKALIGNBYTES); 395 396 sgap = STACKGAPLEN; 397 398 /* 399 * If we have enabled random stackgap, the stack itself has already 400 * been moved from a random location, but is still aligned to a page 401 * boundary. Provide the lower bits of random placement now. 402 */ 403 if (stackgap_random != 0) { 404 sgap += arc4random() & PAGE_MASK; 405 sgap = (sgap + _STACKALIGNBYTES) & ~_STACKALIGNBYTES; 406 } 407 408 /* Now check if args & environ fit into new stack */ 409 len = ((argc + envc + 2 + pack.ep_emul->e_arglen) * sizeof(char *) + 410 sizeof(long) + dp + sgap + sizeof(struct ps_strings)) - argp; 411 412 len = (len + _STACKALIGNBYTES) &~ _STACKALIGNBYTES; 413 414 if (len > pack.ep_ssize) { /* in effect, compare to initial limit */ 415 error = ENOMEM; 416 goto bad; 417 } 418 419 /* adjust "active stack depth" for process VSZ */ 420 pack.ep_ssize = len; /* maybe should go elsewhere, but... */ 421 422 /* 423 * we're committed: any further errors will kill the process, so 424 * kill the other threads now. 425 */ 426 single_thread_set(p, SINGLE_EXIT, 0); 427 428 /* 429 * Prepare vmspace for remapping. Note that uvmspace_exec can replace 430 * ps_vmspace! 431 */ 432 uvmspace_exec(p, VM_MIN_ADDRESS, VM_MAXUSER_ADDRESS); 433 434 vm = pr->ps_vmspace; 435 /* Now map address space */ 436 vm->vm_taddr = (char *)trunc_page(pack.ep_taddr); 437 vm->vm_tsize = atop(round_page(pack.ep_taddr + pack.ep_tsize) - 438 trunc_page(pack.ep_taddr)); 439 vm->vm_daddr = (char *)trunc_page(pack.ep_daddr); 440 vm->vm_dsize = atop(round_page(pack.ep_daddr + pack.ep_dsize) - 441 trunc_page(pack.ep_daddr)); 442 vm->vm_dused = 0; 443 vm->vm_ssize = atop(round_page(pack.ep_ssize)); 444 vm->vm_maxsaddr = (char *)pack.ep_maxsaddr; 445 vm->vm_minsaddr = (char *)pack.ep_minsaddr; 446 447 /* create the new process's VM space by running the vmcmds */ 448 #ifdef DIAGNOSTIC 449 if (pack.ep_vmcmds.evs_used == 0) 450 panic("execve: no vmcmds"); 451 #endif 452 error = exec_process_vmcmds(p, &pack); 453 454 /* if an error happened, deallocate and punt */ 455 if (error) 456 goto exec_abort; 457 458 #ifdef MACHINE_STACK_GROWS_UP 459 pr->ps_strings = (vaddr_t)vm->vm_maxsaddr + sgap; 460 if (uvm_map_protect(&vm->vm_map, (vaddr_t)vm->vm_maxsaddr, 461 trunc_page(pr->ps_strings), PROT_NONE, TRUE)) 462 goto exec_abort; 463 #else 464 pr->ps_strings = (vaddr_t)vm->vm_minsaddr - sizeof(arginfo) - sgap; 465 if (uvm_map_protect(&vm->vm_map, 466 round_page(pr->ps_strings + sizeof(arginfo)), 467 (vaddr_t)vm->vm_minsaddr, PROT_NONE, TRUE)) 468 goto exec_abort; 469 #endif 470 471 /* remember information about the process */ 472 arginfo.ps_nargvstr = argc; 473 arginfo.ps_nenvstr = envc; 474 475 #ifdef MACHINE_STACK_GROWS_UP 476 stack = (char *)vm->vm_maxsaddr + sizeof(arginfo) + sgap; 477 slen = len - sizeof(arginfo) - sgap; 478 #else 479 stack = (char *)(vm->vm_minsaddr - len); 480 #endif 481 /* Now copy argc, args & environ to new stack */ 482 if (!(*pack.ep_emul->e_copyargs)(&pack, &arginfo, stack, argp)) 483 goto exec_abort; 484 485 /* copy out the process's ps_strings structure */ 486 if (copyout(&arginfo, (char *)pr->ps_strings, sizeof(arginfo))) 487 goto exec_abort; 488 489 stopprofclock(pr); /* stop profiling */ 490 fdcloseexec(p); /* handle close on exec */ 491 execsigs(p); /* reset caught signals */ 492 TCB_SET(p, NULL); /* reset the TCB address */ 493 pr->ps_kbind_addr = 0; /* reset the kbind bits */ 494 pr->ps_kbind_cookie = 0; 495 arc4random_buf(&pr->ps_sigcookie, sizeof pr->ps_sigcookie); 496 497 /* set command name & other accounting info */ 498 memset(pr->ps_comm, 0, sizeof(pr->ps_comm)); 499 len = min(nid.ni_cnd.cn_namelen, MAXCOMLEN); 500 memcpy(pr->ps_comm, nid.ni_cnd.cn_nameptr, len); 501 pr->ps_acflag &= ~AFORK; 502 503 /* record proc's vnode, for use by sysctl */ 504 otvp = pr->ps_textvp; 505 vref(pack.ep_vp); 506 pr->ps_textvp = pack.ep_vp; 507 if (otvp) 508 vrele(otvp); 509 510 atomic_setbits_int(&pr->ps_flags, PS_EXEC); 511 if (pr->ps_flags & PS_PPWAIT) { 512 atomic_clearbits_int(&pr->ps_flags, PS_PPWAIT); 513 atomic_clearbits_int(&pr->ps_pptr->ps_flags, PS_ISPWAIT); 514 wakeup(pr->ps_pptr); 515 } 516 517 /* 518 * If process does execve() while it has a mismatched real, 519 * effective, or saved uid/gid, we set PS_SUGIDEXEC. 520 */ 521 if (cred->cr_uid != cred->cr_ruid || 522 cred->cr_uid != cred->cr_svuid || 523 cred->cr_gid != cred->cr_rgid || 524 cred->cr_gid != cred->cr_svgid) 525 atomic_setbits_int(&pr->ps_flags, PS_SUGIDEXEC); 526 else 527 atomic_clearbits_int(&pr->ps_flags, PS_SUGIDEXEC); 528 529 if (pr->ps_flags & PS_EXECPLEDGE) { 530 pr->ps_pledge = pr->ps_execpledge; 531 atomic_setbits_int(&pr->ps_flags, PS_PLEDGE); 532 } else { 533 atomic_clearbits_int(&pr->ps_flags, PS_PLEDGE); 534 pr->ps_pledge = 0; 535 } 536 537 /* 538 * deal with set[ug]id. 539 * MNT_NOEXEC has already been used to disable s[ug]id. 540 */ 541 if ((attr.va_mode & (VSUID | VSGID)) && proc_cansugid(p)) { 542 int i; 543 544 atomic_setbits_int(&pr->ps_flags, PS_SUGID|PS_SUGIDEXEC); 545 546 #ifdef KTRACE 547 /* 548 * If process is being ktraced, turn off - unless 549 * root set it. 550 */ 551 if (pr->ps_tracevp && !(pr->ps_traceflag & KTRFAC_ROOT)) 552 ktrcleartrace(pr); 553 #endif 554 p->p_ucred = cred = crcopy(cred); 555 if (attr.va_mode & VSUID) 556 cred->cr_uid = attr.va_uid; 557 if (attr.va_mode & VSGID) 558 cred->cr_gid = attr.va_gid; 559 560 /* 561 * For set[ug]id processes, a few caveats apply to 562 * stdin, stdout, and stderr. 563 */ 564 error = 0; 565 fdplock(p->p_fd); 566 for (i = 0; i < 3; i++) { 567 struct file *fp = NULL; 568 569 /* 570 * NOTE - This will never return NULL because of 571 * immature fds. The file descriptor table is not 572 * shared because we're suid. 573 */ 574 fp = fd_getfile(p->p_fd, i); 575 576 /* 577 * Ensure that stdin, stdout, and stderr are already 578 * allocated. We do not want userland to accidentally 579 * allocate descriptors in this range which has implied 580 * meaning to libc. 581 */ 582 if (fp == NULL) { 583 short flags = FREAD | (i == 0 ? 0 : FWRITE); 584 struct vnode *vp; 585 int indx; 586 587 if ((error = falloc(p, 0, &fp, &indx)) != 0) 588 break; 589 #ifdef DIAGNOSTIC 590 if (indx != i) 591 panic("sys_execve: falloc indx != i"); 592 #endif 593 if ((error = cdevvp(getnulldev(), &vp)) != 0) { 594 fdremove(p->p_fd, indx); 595 closef(fp, p); 596 break; 597 } 598 if ((error = VOP_OPEN(vp, flags, cred, p)) != 0) { 599 fdremove(p->p_fd, indx); 600 closef(fp, p); 601 vrele(vp); 602 break; 603 } 604 if (flags & FWRITE) 605 vp->v_writecount++; 606 fp->f_flag = flags; 607 fp->f_type = DTYPE_VNODE; 608 fp->f_ops = &vnops; 609 fp->f_data = (caddr_t)vp; 610 FILE_SET_MATURE(fp, p); 611 } 612 } 613 fdpunlock(p->p_fd); 614 if (error) 615 goto exec_abort; 616 } else 617 atomic_clearbits_int(&pr->ps_flags, PS_SUGID); 618 619 /* 620 * Reset the saved ugids and update the process's copy of the 621 * creds if the creds have been changed 622 */ 623 if (cred->cr_uid != cred->cr_svuid || 624 cred->cr_gid != cred->cr_svgid) { 625 /* make sure we have unshared ucreds */ 626 p->p_ucred = cred = crcopy(cred); 627 cred->cr_svuid = cred->cr_uid; 628 cred->cr_svgid = cred->cr_gid; 629 } 630 631 if (pr->ps_ucred != cred) { 632 struct ucred *ocred; 633 634 ocred = pr->ps_ucred; 635 crhold(cred); 636 pr->ps_ucred = cred; 637 crfree(ocred); 638 } 639 640 if (pr->ps_flags & PS_SUGIDEXEC) { 641 int i, s = splclock(); 642 643 timeout_del(&pr->ps_realit_to); 644 for (i = 0; i < nitems(pr->ps_timer); i++) { 645 timerclear(&pr->ps_timer[i].it_interval); 646 timerclear(&pr->ps_timer[i].it_value); 647 } 648 splx(s); 649 } 650 651 /* reset CPU time usage for the thread, but not the process */ 652 timespecclear(&p->p_tu.tu_runtime); 653 p->p_tu.tu_uticks = p->p_tu.tu_sticks = p->p_tu.tu_iticks = 0; 654 655 km_free(argp, NCARGS, &kv_exec, &kp_pageable); 656 657 pool_put(&namei_pool, nid.ni_cnd.cn_pnbuf); 658 vn_close(pack.ep_vp, FREAD, cred, p); 659 660 /* 661 * notify others that we exec'd 662 */ 663 KNOTE(&pr->ps_klist, NOTE_EXEC); 664 665 /* setup new registers and do misc. setup. */ 666 if (pack.ep_emul->e_fixup != NULL) { 667 if ((*pack.ep_emul->e_fixup)(p, &pack) != 0) 668 goto free_pack_abort; 669 } 670 #ifdef MACHINE_STACK_GROWS_UP 671 (*pack.ep_emul->e_setregs)(p, &pack, (u_long)stack + slen, retval); 672 #else 673 (*pack.ep_emul->e_setregs)(p, &pack, (u_long)stack, retval); 674 #endif 675 676 /* map the process's signal trampoline code */ 677 if (exec_sigcode_map(pr, pack.ep_emul)) 678 goto free_pack_abort; 679 680 #ifdef __HAVE_EXEC_MD_MAP 681 /* perform md specific mappings that process might need */ 682 if (exec_md_map(p, &pack)) 683 goto free_pack_abort; 684 #endif 685 686 if (pr->ps_flags & PS_TRACED) 687 psignal(p, SIGTRAP); 688 689 free(pack.ep_hdr, M_EXEC, pack.ep_hdrlen); 690 691 p->p_descfd = 255; 692 if ((pack.ep_flags & EXEC_HASFD) && pack.ep_fd < 255) 693 p->p_descfd = pack.ep_fd; 694 695 if (pack.ep_flags & EXEC_WXNEEDED) 696 p->p_p->ps_flags |= PS_WXNEEDED; 697 else 698 p->p_p->ps_flags &= ~PS_WXNEEDED; 699 700 /* update ps_emul, the old value is no longer needed */ 701 pr->ps_emul = pack.ep_emul; 702 703 atomic_clearbits_int(&pr->ps_flags, PS_INEXEC); 704 single_thread_clear(p, P_SUSPSIG); 705 706 return (0); 707 708 bad: 709 /* free the vmspace-creation commands, and release their references */ 710 kill_vmcmds(&pack.ep_vmcmds); 711 /* kill any opened file descriptor, if necessary */ 712 if (pack.ep_flags & EXEC_HASFD) { 713 pack.ep_flags &= ~EXEC_HASFD; 714 fdplock(p->p_fd); 715 (void) fdrelease(p, pack.ep_fd); 716 fdpunlock(p->p_fd); 717 } 718 if (pack.ep_interp != NULL) 719 pool_put(&namei_pool, pack.ep_interp); 720 if (pack.ep_emul_arg != NULL) 721 free(pack.ep_emul_arg, M_TEMP, pack.ep_emul_argsize); 722 /* close and put the exec'd file */ 723 vn_close(pack.ep_vp, FREAD, cred, p); 724 pool_put(&namei_pool, nid.ni_cnd.cn_pnbuf); 725 km_free(argp, NCARGS, &kv_exec, &kp_pageable); 726 727 freehdr: 728 free(pack.ep_hdr, M_EXEC, pack.ep_hdrlen); 729 atomic_clearbits_int(&pr->ps_flags, PS_INEXEC); 730 single_thread_clear(p, P_SUSPSIG); 731 732 return (error); 733 734 exec_abort: 735 /* 736 * the old process doesn't exist anymore. exit gracefully. 737 * get rid of the (new) address space we have created, if any, get rid 738 * of our namei data and vnode, and exit noting failure 739 */ 740 uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, 741 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); 742 if (pack.ep_interp != NULL) 743 pool_put(&namei_pool, pack.ep_interp); 744 if (pack.ep_emul_arg != NULL) 745 free(pack.ep_emul_arg, M_TEMP, pack.ep_emul_argsize); 746 pool_put(&namei_pool, nid.ni_cnd.cn_pnbuf); 747 vn_close(pack.ep_vp, FREAD, cred, p); 748 km_free(argp, NCARGS, &kv_exec, &kp_pageable); 749 750 free_pack_abort: 751 free(pack.ep_hdr, M_EXEC, pack.ep_hdrlen); 752 exit1(p, W_EXITCODE(0, SIGABRT), EXIT_NORMAL); 753 754 /* NOTREACHED */ 755 atomic_clearbits_int(&pr->ps_flags, PS_INEXEC); 756 757 return (0); 758 } 759 760 761 void * 762 copyargs(struct exec_package *pack, struct ps_strings *arginfo, void *stack, 763 void *argp) 764 { 765 char **cpp = stack; 766 char *dp, *sp; 767 size_t len; 768 void *nullp = NULL; 769 long argc = arginfo->ps_nargvstr; 770 int envc = arginfo->ps_nenvstr; 771 772 if (copyout(&argc, cpp++, sizeof(argc))) 773 return (NULL); 774 775 dp = (char *) (cpp + argc + envc + 2 + pack->ep_emul->e_arglen); 776 sp = argp; 777 778 /* XXX don't copy them out, remap them! */ 779 arginfo->ps_argvstr = cpp; /* remember location of argv for later */ 780 781 for (; --argc >= 0; sp += len, dp += len) 782 if (copyout(&dp, cpp++, sizeof(dp)) || 783 copyoutstr(sp, dp, ARG_MAX, &len)) 784 return (NULL); 785 786 if (copyout(&nullp, cpp++, sizeof(nullp))) 787 return (NULL); 788 789 arginfo->ps_envstr = cpp; /* remember location of envp for later */ 790 791 for (; --envc >= 0; sp += len, dp += len) 792 if (copyout(&dp, cpp++, sizeof(dp)) || 793 copyoutstr(sp, dp, ARG_MAX, &len)) 794 return (NULL); 795 796 if (copyout(&nullp, cpp++, sizeof(nullp))) 797 return (NULL); 798 799 return (cpp); 800 } 801 802 int 803 exec_sigcode_map(struct process *pr, struct emul *e) 804 { 805 vsize_t sz; 806 807 sz = (vaddr_t)e->e_esigcode - (vaddr_t)e->e_sigcode; 808 809 /* 810 * If we don't have a sigobject for this emulation, create one. 811 * 812 * sigobject is an anonymous memory object (just like SYSV shared 813 * memory) that we keep a permanent reference to and that we map 814 * in all processes that need this sigcode. The creation is simple, 815 * we create an object, add a permanent reference to it, map it in 816 * kernel space, copy out the sigcode to it and unmap it. 817 * Then we map it with PROT_READ|PROT_EXEC into the process just 818 * the way sys_mmap would map it. 819 */ 820 if (e->e_sigobject == NULL) { 821 extern int sigfillsiz; 822 extern u_char sigfill[]; 823 size_t off; 824 vaddr_t va; 825 int r; 826 827 e->e_sigobject = uao_create(sz, 0); 828 uao_reference(e->e_sigobject); /* permanent reference */ 829 830 if ((r = uvm_map(kernel_map, &va, round_page(sz), e->e_sigobject, 831 0, 0, UVM_MAPFLAG(PROT_READ | PROT_WRITE, PROT_READ | PROT_WRITE, 832 MAP_INHERIT_SHARE, MADV_RANDOM, 0)))) { 833 uao_detach(e->e_sigobject); 834 return (ENOMEM); 835 } 836 837 for (off = 0; off < round_page(sz); off += sigfillsiz) 838 memcpy((caddr_t)va + off, sigfill, sigfillsiz); 839 memcpy((caddr_t)va, e->e_sigcode, sz); 840 uvm_unmap(kernel_map, va, va + round_page(sz)); 841 } 842 843 pr->ps_sigcode = 0; /* no hint */ 844 uao_reference(e->e_sigobject); 845 if (uvm_map(&pr->ps_vmspace->vm_map, &pr->ps_sigcode, round_page(sz), 846 e->e_sigobject, 0, 0, UVM_MAPFLAG(PROT_READ | PROT_EXEC, 847 PROT_READ | PROT_WRITE | PROT_EXEC, MAP_INHERIT_COPY, 848 MADV_RANDOM, UVM_FLAG_COPYONW))) { 849 uao_detach(e->e_sigobject); 850 return (ENOMEM); 851 } 852 853 /* Calculate PC at point of sigreturn entry */ 854 pr->ps_sigcoderet = pr->ps_sigcode + 855 (pr->ps_emul->e_esigret - pr->ps_emul->e_sigcode); 856 857 return (0); 858 } 859