1 /* $NetBSD: kern_exec.c,v 1.417 2015/09/26 16:12:24 maxv Exp $ */ 2 3 /*- 4 * Copyright (c) 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /*- 30 * Copyright (C) 1993, 1994, 1996 Christopher G. Demetriou 31 * Copyright (C) 1992 Wolfgang Solfrank. 32 * Copyright (C) 1992 TooLs GmbH. 33 * All rights reserved. 34 * 35 * Redistribution and use in source and binary forms, with or without 36 * modification, are permitted provided that the following conditions 37 * are met: 38 * 1. Redistributions of source code must retain the above copyright 39 * notice, this list of conditions and the following disclaimer. 40 * 2. Redistributions in binary form must reproduce the above copyright 41 * notice, this list of conditions and the following disclaimer in the 42 * documentation and/or other materials provided with the distribution. 43 * 3. All advertising materials mentioning features or use of this software 44 * must display the following acknowledgement: 45 * This product includes software developed by TooLs GmbH. 46 * 4. The name of TooLs GmbH may not be used to endorse or promote products 47 * derived from this software without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 50 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 51 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 52 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 53 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 54 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 55 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 56 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 57 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 58 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 59 */ 60 61 #include <sys/cdefs.h> 62 __KERNEL_RCSID(0, "$NetBSD: kern_exec.c,v 1.417 2015/09/26 16:12:24 maxv Exp $"); 63 64 #include "opt_exec.h" 65 #include "opt_execfmt.h" 66 #include "opt_ktrace.h" 67 #include "opt_modular.h" 68 #include "opt_syscall_debug.h" 69 #include "veriexec.h" 70 #include "opt_pax.h" 71 72 #include <sys/param.h> 73 #include <sys/systm.h> 74 #include <sys/filedesc.h> 75 #include <sys/kernel.h> 76 #include <sys/proc.h> 77 #include <sys/mount.h> 78 #include <sys/kmem.h> 79 #include <sys/namei.h> 80 #include <sys/vnode.h> 81 #include <sys/file.h> 82 #include <sys/filedesc.h> 83 #include <sys/acct.h> 84 #include <sys/atomic.h> 85 #include <sys/exec.h> 86 #include <sys/ktrace.h> 87 #include <sys/uidinfo.h> 88 #include <sys/wait.h> 89 #include <sys/mman.h> 90 #include <sys/ras.h> 91 #include <sys/signalvar.h> 92 #include <sys/stat.h> 93 #include <sys/syscall.h> 94 #include <sys/kauth.h> 95 #include <sys/lwpctl.h> 96 #include <sys/pax.h> 97 #include <sys/cpu.h> 98 #include <sys/module.h> 99 #include <sys/syscallvar.h> 100 #include <sys/syscallargs.h> 101 #if NVERIEXEC > 0 102 #include <sys/verified_exec.h> 103 #endif /* NVERIEXEC > 0 */ 104 #include <sys/sdt.h> 105 #include <sys/spawn.h> 106 #include <sys/prot.h> 107 #include <sys/cprng.h> 108 109 #include <uvm/uvm_extern.h> 110 111 #include <machine/reg.h> 112 113 #include <compat/common/compat_util.h> 114 115 #ifndef MD_TOPDOWN_INIT 116 #ifdef __USE_TOPDOWN_VM 117 #define MD_TOPDOWN_INIT(epp) (epp)->ep_flags |= EXEC_TOPDOWN_VM 118 #else 119 #define MD_TOPDOWN_INIT(epp) 120 #endif 121 #endif 122 123 struct execve_data; 124 125 static size_t calcargs(struct execve_data * restrict, const size_t); 126 static size_t calcstack(struct execve_data * restrict, const size_t); 127 static int copyoutargs(struct execve_data * restrict, struct lwp *, 128 char * const); 129 static int copyoutpsstrs(struct execve_data * restrict, struct proc *); 130 static int copyinargs(struct execve_data * restrict, char * const *, 131 char * const *, execve_fetch_element_t, char **); 132 static int copyinargstrs(struct execve_data * restrict, char * const *, 133 execve_fetch_element_t, char **, size_t *, void (*)(const void *, size_t)); 134 static int exec_sigcode_map(struct proc *, const struct emul *); 135 136 #ifdef DEBUG_EXEC 137 #define DPRINTF(a) printf a 138 #define COPYPRINTF(s, a, b) printf("%s, %d: copyout%s @%p %zu\n", __func__, \ 139 __LINE__, (s), (a), (b)) 140 static void dump_vmcmds(const struct exec_package * const, size_t, int); 141 #define DUMPVMCMDS(p, x, e) do { dump_vmcmds((p), (x), (e)); } while (0) 142 #else 143 #define DPRINTF(a) 144 #define COPYPRINTF(s, a, b) 145 #define DUMPVMCMDS(p, x, e) do {} while (0) 146 #endif /* DEBUG_EXEC */ 147 148 /* 149 * DTrace SDT provider definitions 150 */ 151 SDT_PROBE_DEFINE(proc,,,exec,exec, 152 "char *", NULL, 153 NULL, NULL, NULL, NULL, 154 NULL, NULL, NULL, NULL); 155 SDT_PROBE_DEFINE(proc,,,exec_success,exec-success, 156 "char *", NULL, 157 NULL, NULL, NULL, NULL, 158 NULL, NULL, NULL, NULL); 159 SDT_PROBE_DEFINE(proc,,,exec_failure,exec-failure, 160 "int", NULL, 161 NULL, NULL, NULL, NULL, 162 NULL, NULL, NULL, NULL); 163 164 /* 165 * Exec function switch: 166 * 167 * Note that each makecmds function is responsible for loading the 168 * exec package with the necessary functions for any exec-type-specific 169 * handling. 170 * 171 * Functions for specific exec types should be defined in their own 172 * header file. 173 */ 174 static const struct execsw **execsw = NULL; 175 static int nexecs; 176 177 u_int exec_maxhdrsz; /* must not be static - used by netbsd32 */ 178 179 /* list of dynamically loaded execsw entries */ 180 static LIST_HEAD(execlist_head, exec_entry) ex_head = 181 LIST_HEAD_INITIALIZER(ex_head); 182 struct exec_entry { 183 LIST_ENTRY(exec_entry) ex_list; 184 SLIST_ENTRY(exec_entry) ex_slist; 185 const struct execsw *ex_sw; 186 }; 187 188 #ifndef __HAVE_SYSCALL_INTERN 189 void syscall(void); 190 #endif 191 192 /* NetBSD emul struct */ 193 struct emul emul_netbsd = { 194 .e_name = "netbsd", 195 #ifdef EMUL_NATIVEROOT 196 .e_path = EMUL_NATIVEROOT, 197 #else 198 .e_path = NULL, 199 #endif 200 #ifndef __HAVE_MINIMAL_EMUL 201 .e_flags = EMUL_HAS_SYS___syscall, 202 .e_errno = NULL, 203 .e_nosys = SYS_syscall, 204 .e_nsysent = SYS_NSYSENT, 205 #endif 206 .e_sysent = sysent, 207 #ifdef SYSCALL_DEBUG 208 .e_syscallnames = syscallnames, 209 #else 210 .e_syscallnames = NULL, 211 #endif 212 .e_sendsig = sendsig, 213 .e_trapsignal = trapsignal, 214 .e_tracesig = NULL, 215 .e_sigcode = NULL, 216 .e_esigcode = NULL, 217 .e_sigobject = NULL, 218 .e_setregs = setregs, 219 .e_proc_exec = NULL, 220 .e_proc_fork = NULL, 221 .e_proc_exit = NULL, 222 .e_lwp_fork = NULL, 223 .e_lwp_exit = NULL, 224 #ifdef __HAVE_SYSCALL_INTERN 225 .e_syscall_intern = syscall_intern, 226 #else 227 .e_syscall = syscall, 228 #endif 229 .e_sysctlovly = NULL, 230 .e_fault = NULL, 231 .e_vm_default_addr = uvm_default_mapaddr, 232 .e_usertrap = NULL, 233 .e_ucsize = sizeof(ucontext_t), 234 .e_startlwp = startlwp 235 }; 236 237 /* 238 * Exec lock. Used to control access to execsw[] structures. 239 * This must not be static so that netbsd32 can access it, too. 240 */ 241 krwlock_t exec_lock; 242 243 static kmutex_t sigobject_lock; 244 245 /* 246 * Data used between a loadvm and execve part of an "exec" operation 247 */ 248 struct execve_data { 249 struct exec_package ed_pack; 250 struct pathbuf *ed_pathbuf; 251 struct vattr ed_attr; 252 struct ps_strings ed_arginfo; 253 char *ed_argp; 254 const char *ed_pathstring; 255 char *ed_resolvedpathbuf; 256 size_t ed_ps_strings_sz; 257 int ed_szsigcode; 258 size_t ed_argslen; 259 long ed_argc; 260 long ed_envc; 261 }; 262 263 /* 264 * data passed from parent lwp to child during a posix_spawn() 265 */ 266 struct spawn_exec_data { 267 struct execve_data sed_exec; 268 struct posix_spawn_file_actions 269 *sed_actions; 270 struct posix_spawnattr *sed_attrs; 271 struct proc *sed_parent; 272 kcondvar_t sed_cv_child_ready; 273 kmutex_t sed_mtx_child; 274 int sed_error; 275 volatile uint32_t sed_refcnt; 276 }; 277 278 static void * 279 exec_pool_alloc(struct pool *pp, int flags) 280 { 281 282 return (void *)uvm_km_alloc(kernel_map, NCARGS, 0, 283 UVM_KMF_PAGEABLE | UVM_KMF_WAITVA); 284 } 285 286 static void 287 exec_pool_free(struct pool *pp, void *addr) 288 { 289 290 uvm_km_free(kernel_map, (vaddr_t)addr, NCARGS, UVM_KMF_PAGEABLE); 291 } 292 293 static struct pool exec_pool; 294 295 static struct pool_allocator exec_palloc = { 296 .pa_alloc = exec_pool_alloc, 297 .pa_free = exec_pool_free, 298 .pa_pagesz = NCARGS 299 }; 300 301 /* 302 * check exec: 303 * given an "executable" described in the exec package's namei info, 304 * see what we can do with it. 305 * 306 * ON ENTRY: 307 * exec package with appropriate namei info 308 * lwp pointer of exec'ing lwp 309 * NO SELF-LOCKED VNODES 310 * 311 * ON EXIT: 312 * error: nothing held, etc. exec header still allocated. 313 * ok: filled exec package, executable's vnode (unlocked). 314 * 315 * EXEC SWITCH ENTRY: 316 * Locked vnode to check, exec package, proc. 317 * 318 * EXEC SWITCH EXIT: 319 * ok: return 0, filled exec package, executable's vnode (unlocked). 320 * error: destructive: 321 * everything deallocated execept exec header. 322 * non-destructive: 323 * error code, executable's vnode (unlocked), 324 * exec header unmodified. 325 */ 326 int 327 /*ARGSUSED*/ 328 check_exec(struct lwp *l, struct exec_package *epp, struct pathbuf *pb) 329 { 330 int error, i; 331 struct vnode *vp; 332 struct nameidata nd; 333 size_t resid; 334 335 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | TRYEMULROOT, pb); 336 337 /* first get the vnode */ 338 if ((error = namei(&nd)) != 0) 339 return error; 340 epp->ep_vp = vp = nd.ni_vp; 341 /* normally this can't fail */ 342 error = copystr(nd.ni_pnbuf, epp->ep_resolvedname, PATH_MAX, NULL); 343 KASSERT(error == 0); 344 345 #ifdef DIAGNOSTIC 346 /* paranoia (take this out once namei stuff stabilizes) */ 347 memset(nd.ni_pnbuf, '~', PATH_MAX); 348 #endif 349 350 /* check access and type */ 351 if (vp->v_type != VREG) { 352 error = EACCES; 353 goto bad1; 354 } 355 if ((error = VOP_ACCESS(vp, VEXEC, l->l_cred)) != 0) 356 goto bad1; 357 358 /* get attributes */ 359 if ((error = VOP_GETATTR(vp, epp->ep_vap, l->l_cred)) != 0) 360 goto bad1; 361 362 /* Check mount point */ 363 if (vp->v_mount->mnt_flag & MNT_NOEXEC) { 364 error = EACCES; 365 goto bad1; 366 } 367 if (vp->v_mount->mnt_flag & MNT_NOSUID) 368 epp->ep_vap->va_mode &= ~(S_ISUID | S_ISGID); 369 370 /* try to open it */ 371 if ((error = VOP_OPEN(vp, FREAD, l->l_cred)) != 0) 372 goto bad1; 373 374 /* unlock vp, since we need it unlocked from here on out. */ 375 VOP_UNLOCK(vp); 376 377 #if NVERIEXEC > 0 378 error = veriexec_verify(l, vp, epp->ep_resolvedname, 379 epp->ep_flags & EXEC_INDIR ? VERIEXEC_INDIRECT : VERIEXEC_DIRECT, 380 NULL); 381 if (error) 382 goto bad2; 383 #endif /* NVERIEXEC > 0 */ 384 385 #ifdef PAX_SEGVGUARD 386 error = pax_segvguard(l, vp, epp->ep_resolvedname, false); 387 if (error) 388 goto bad2; 389 #endif /* PAX_SEGVGUARD */ 390 391 /* now we have the file, get the exec header */ 392 error = vn_rdwr(UIO_READ, vp, epp->ep_hdr, epp->ep_hdrlen, 0, 393 UIO_SYSSPACE, 0, l->l_cred, &resid, NULL); 394 if (error) 395 goto bad2; 396 epp->ep_hdrvalid = epp->ep_hdrlen - resid; 397 398 /* 399 * Set up default address space limits. Can be overridden 400 * by individual exec packages. 401 * 402 * XXX probably should be all done in the exec packages. 403 */ 404 epp->ep_vm_minaddr = VM_MIN_ADDRESS; 405 epp->ep_vm_maxaddr = VM_MAXUSER_ADDRESS; 406 /* 407 * set up the vmcmds for creation of the process 408 * address space 409 */ 410 error = ENOEXEC; 411 for (i = 0; i < nexecs; i++) { 412 int newerror; 413 414 epp->ep_esch = execsw[i]; 415 newerror = (*execsw[i]->es_makecmds)(l, epp); 416 417 if (!newerror) { 418 /* Seems ok: check that entry point is not too high */ 419 if (epp->ep_entry > epp->ep_vm_maxaddr) { 420 #ifdef DIAGNOSTIC 421 printf("%s: rejecting %p due to " 422 "too high entry address (> %p)\n", 423 __func__, (void *)epp->ep_entry, 424 (void *)epp->ep_vm_maxaddr); 425 #endif 426 error = ENOEXEC; 427 break; 428 } 429 /* Seems ok: check that entry point is not too low */ 430 if (epp->ep_entry < epp->ep_vm_minaddr) { 431 #ifdef DIAGNOSTIC 432 printf("%s: rejecting %p due to " 433 "too low entry address (< %p)\n", 434 __func__, (void *)epp->ep_entry, 435 (void *)epp->ep_vm_minaddr); 436 #endif 437 error = ENOEXEC; 438 break; 439 } 440 441 /* check limits */ 442 if ((epp->ep_tsize > MAXTSIZ) || 443 (epp->ep_dsize > (u_quad_t)l->l_proc->p_rlimit 444 [RLIMIT_DATA].rlim_cur)) { 445 #ifdef DIAGNOSTIC 446 printf("%s: rejecting due to " 447 "limits (t=%llu > %llu || d=%llu > %llu)\n", 448 __func__, 449 (unsigned long long)epp->ep_tsize, 450 (unsigned long long)MAXTSIZ, 451 (unsigned long long)epp->ep_dsize, 452 (unsigned long long) 453 l->l_proc->p_rlimit[RLIMIT_DATA].rlim_cur); 454 #endif 455 error = ENOMEM; 456 break; 457 } 458 return 0; 459 } 460 461 if (epp->ep_emul_root != NULL) { 462 vrele(epp->ep_emul_root); 463 epp->ep_emul_root = NULL; 464 } 465 if (epp->ep_interp != NULL) { 466 vrele(epp->ep_interp); 467 epp->ep_interp = NULL; 468 } 469 470 /* make sure the first "interesting" error code is saved. */ 471 if (error == ENOEXEC) 472 error = newerror; 473 474 if (epp->ep_flags & EXEC_DESTR) 475 /* Error from "#!" code, tidied up by recursive call */ 476 return error; 477 } 478 479 /* not found, error */ 480 481 /* 482 * free any vmspace-creation commands, 483 * and release their references 484 */ 485 kill_vmcmds(&epp->ep_vmcmds); 486 487 bad2: 488 /* 489 * close and release the vnode, restore the old one, free the 490 * pathname buf, and punt. 491 */ 492 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 493 VOP_CLOSE(vp, FREAD, l->l_cred); 494 vput(vp); 495 return error; 496 497 bad1: 498 /* 499 * free the namei pathname buffer, and put the vnode 500 * (which we don't yet have open). 501 */ 502 vput(vp); /* was still locked */ 503 return error; 504 } 505 506 #ifdef __MACHINE_STACK_GROWS_UP 507 #define STACK_PTHREADSPACE NBPG 508 #else 509 #define STACK_PTHREADSPACE 0 510 #endif 511 512 static int 513 execve_fetch_element(char * const *array, size_t index, char **value) 514 { 515 return copyin(array + index, value, sizeof(*value)); 516 } 517 518 /* 519 * exec system call 520 */ 521 int 522 sys_execve(struct lwp *l, const struct sys_execve_args *uap, register_t *retval) 523 { 524 /* { 525 syscallarg(const char *) path; 526 syscallarg(char * const *) argp; 527 syscallarg(char * const *) envp; 528 } */ 529 530 return execve1(l, SCARG(uap, path), SCARG(uap, argp), 531 SCARG(uap, envp), execve_fetch_element); 532 } 533 534 int 535 sys_fexecve(struct lwp *l, const struct sys_fexecve_args *uap, 536 register_t *retval) 537 { 538 /* { 539 syscallarg(int) fd; 540 syscallarg(char * const *) argp; 541 syscallarg(char * const *) envp; 542 } */ 543 544 return ENOSYS; 545 } 546 547 /* 548 * Load modules to try and execute an image that we do not understand. 549 * If no execsw entries are present, we load those likely to be needed 550 * in order to run native images only. Otherwise, we autoload all 551 * possible modules that could let us run the binary. XXX lame 552 */ 553 static void 554 exec_autoload(void) 555 { 556 #ifdef MODULAR 557 static const char * const native[] = { 558 "exec_elf32", 559 "exec_elf64", 560 "exec_script", 561 NULL 562 }; 563 static const char * const compat[] = { 564 "exec_elf32", 565 "exec_elf64", 566 "exec_script", 567 "exec_aout", 568 "exec_coff", 569 "exec_ecoff", 570 "compat_aoutm68k", 571 "compat_freebsd", 572 "compat_ibcs2", 573 "compat_linux", 574 "compat_linux32", 575 "compat_netbsd32", 576 "compat_sunos", 577 "compat_sunos32", 578 "compat_svr4", 579 "compat_svr4_32", 580 "compat_ultrix", 581 NULL 582 }; 583 char const * const *list; 584 int i; 585 586 list = (nexecs == 0 ? native : compat); 587 for (i = 0; list[i] != NULL; i++) { 588 if (module_autoload(list[i], MODULE_CLASS_EXEC) != 0) { 589 continue; 590 } 591 yield(); 592 } 593 #endif 594 } 595 596 static int 597 makepathbuf(struct lwp *l, const char *upath, struct pathbuf **pbp, 598 size_t *offs) 599 { 600 char *path, *bp; 601 size_t len, tlen; 602 int error; 603 struct cwdinfo *cwdi; 604 605 path = PNBUF_GET(); 606 error = copyinstr(upath, path, MAXPATHLEN, &len); 607 if (error) { 608 PNBUF_PUT(path); 609 DPRINTF(("%s: copyin path @%p %d\n", __func__, upath, error)); 610 return error; 611 } 612 613 if (path[0] == '/') { 614 *offs = 0; 615 goto out; 616 } 617 618 len++; 619 if (len + 1 >= MAXPATHLEN) 620 goto out; 621 bp = path + MAXPATHLEN - len; 622 memmove(bp, path, len); 623 *(--bp) = '/'; 624 625 cwdi = l->l_proc->p_cwdi; 626 rw_enter(&cwdi->cwdi_lock, RW_READER); 627 error = getcwd_common(cwdi->cwdi_cdir, NULL, &bp, path, MAXPATHLEN / 2, 628 GETCWD_CHECK_ACCESS, l); 629 rw_exit(&cwdi->cwdi_lock); 630 631 if (error) { 632 DPRINTF(("%s: getcwd_common path %s %d\n", __func__, path, 633 error)); 634 goto out; 635 } 636 tlen = path + MAXPATHLEN - bp; 637 638 memmove(path, bp, tlen); 639 path[tlen] = '\0'; 640 *offs = tlen - len; 641 out: 642 *pbp = pathbuf_assimilate(path); 643 return 0; 644 } 645 646 static int 647 execve_loadvm(struct lwp *l, const char *path, char * const *args, 648 char * const *envs, execve_fetch_element_t fetch_element, 649 struct execve_data * restrict data) 650 { 651 struct exec_package * const epp = &data->ed_pack; 652 int error; 653 struct proc *p; 654 char *dp; 655 u_int modgen; 656 size_t offs = 0; // XXX: GCC 657 658 KASSERT(data != NULL); 659 660 p = l->l_proc; 661 modgen = 0; 662 663 SDT_PROBE(proc,,,exec, path, 0, 0, 0, 0); 664 665 /* 666 * Check if we have exceeded our number of processes limit. 667 * This is so that we handle the case where a root daemon 668 * forked, ran setuid to become the desired user and is trying 669 * to exec. The obvious place to do the reference counting check 670 * is setuid(), but we don't do the reference counting check there 671 * like other OS's do because then all the programs that use setuid() 672 * must be modified to check the return code of setuid() and exit(). 673 * It is dangerous to make setuid() fail, because it fails open and 674 * the program will continue to run as root. If we make it succeed 675 * and return an error code, again we are not enforcing the limit. 676 * The best place to enforce the limit is here, when the process tries 677 * to execute a new image, because eventually the process will need 678 * to call exec in order to do something useful. 679 */ 680 retry: 681 if (p->p_flag & PK_SUGID) { 682 if (kauth_authorize_process(l->l_cred, KAUTH_PROCESS_RLIMIT, 683 p, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_BYPASS), 684 &p->p_rlimit[RLIMIT_NPROC], 685 KAUTH_ARG(RLIMIT_NPROC)) != 0 && 686 chgproccnt(kauth_cred_getuid(l->l_cred), 0) > 687 p->p_rlimit[RLIMIT_NPROC].rlim_cur) 688 return EAGAIN; 689 } 690 691 /* 692 * Drain existing references and forbid new ones. The process 693 * should be left alone until we're done here. This is necessary 694 * to avoid race conditions - e.g. in ptrace() - that might allow 695 * a local user to illicitly obtain elevated privileges. 696 */ 697 rw_enter(&p->p_reflock, RW_WRITER); 698 699 /* 700 * Init the namei data to point the file user's program name. 701 * This is done here rather than in check_exec(), so that it's 702 * possible to override this settings if any of makecmd/probe 703 * functions call check_exec() recursively - for example, 704 * see exec_script_makecmds(). 705 */ 706 if ((error = makepathbuf(l, path, &data->ed_pathbuf, &offs)) != 0) 707 goto clrflg; 708 data->ed_pathstring = pathbuf_stringcopy_get(data->ed_pathbuf); 709 data->ed_resolvedpathbuf = PNBUF_GET(); 710 711 /* 712 * initialize the fields of the exec package. 713 */ 714 epp->ep_kname = data->ed_pathstring + offs; 715 epp->ep_resolvedname = data->ed_resolvedpathbuf; 716 epp->ep_hdr = kmem_alloc(exec_maxhdrsz, KM_SLEEP); 717 epp->ep_hdrlen = exec_maxhdrsz; 718 epp->ep_hdrvalid = 0; 719 epp->ep_emul_arg = NULL; 720 epp->ep_emul_arg_free = NULL; 721 memset(&epp->ep_vmcmds, 0, sizeof(epp->ep_vmcmds)); 722 epp->ep_vap = &data->ed_attr; 723 epp->ep_flags = (p->p_flag & PK_32) ? EXEC_FROM32 : 0; 724 MD_TOPDOWN_INIT(epp); 725 epp->ep_emul_root = NULL; 726 epp->ep_interp = NULL; 727 epp->ep_esch = NULL; 728 epp->ep_pax_flags = 0; 729 memset(epp->ep_machine_arch, 0, sizeof(epp->ep_machine_arch)); 730 731 rw_enter(&exec_lock, RW_READER); 732 733 /* see if we can run it. */ 734 if ((error = check_exec(l, epp, data->ed_pathbuf)) != 0) { 735 if (error != ENOENT) { 736 DPRINTF(("%s: check exec failed %d\n", 737 __func__, error)); 738 } 739 goto freehdr; 740 } 741 742 /* allocate an argument buffer */ 743 data->ed_argp = pool_get(&exec_pool, PR_WAITOK); 744 KASSERT(data->ed_argp != NULL); 745 dp = data->ed_argp; 746 747 if ((error = copyinargs(data, args, envs, fetch_element, &dp)) != 0) { 748 goto bad; 749 } 750 751 /* 752 * Calculate the new stack size. 753 */ 754 755 #ifdef PAX_ASLR 756 #define ASLR_GAP(epp) (pax_aslr_epp_active(epp) ? (cprng_fast32() % PAGE_SIZE) : 0) 757 #else 758 #define ASLR_GAP(epp) 0 759 #endif 760 761 #ifdef __MACHINE_STACK_GROWS_UP 762 /* 763 * copyargs() fills argc/argv/envp from the lower address even on 764 * __MACHINE_STACK_GROWS_UP machines. Reserve a few words just below the SP 765 * so that _rtld() use it. 766 */ 767 #define RTLD_GAP 32 768 #else 769 #define RTLD_GAP 0 770 #endif 771 772 const size_t argenvstrlen = (char *)ALIGN(dp) - data->ed_argp; 773 774 data->ed_argslen = calcargs(data, argenvstrlen); 775 776 const size_t len = calcstack(data, ASLR_GAP(epp) + RTLD_GAP); 777 778 if (len > epp->ep_ssize) { 779 /* in effect, compare to initial limit */ 780 DPRINTF(("%s: stack limit exceeded %zu\n", __func__, len)); 781 error = ENOMEM; 782 goto bad; 783 } 784 /* adjust "active stack depth" for process VSZ */ 785 epp->ep_ssize = len; 786 787 return 0; 788 789 bad: 790 /* free the vmspace-creation commands, and release their references */ 791 kill_vmcmds(&epp->ep_vmcmds); 792 /* kill any opened file descriptor, if necessary */ 793 if (epp->ep_flags & EXEC_HASFD) { 794 epp->ep_flags &= ~EXEC_HASFD; 795 fd_close(epp->ep_fd); 796 } 797 /* close and put the exec'd file */ 798 vn_lock(epp->ep_vp, LK_EXCLUSIVE | LK_RETRY); 799 VOP_CLOSE(epp->ep_vp, FREAD, l->l_cred); 800 vput(epp->ep_vp); 801 pool_put(&exec_pool, data->ed_argp); 802 803 freehdr: 804 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 805 if (epp->ep_emul_root != NULL) 806 vrele(epp->ep_emul_root); 807 if (epp->ep_interp != NULL) 808 vrele(epp->ep_interp); 809 810 rw_exit(&exec_lock); 811 812 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 813 pathbuf_destroy(data->ed_pathbuf); 814 PNBUF_PUT(data->ed_resolvedpathbuf); 815 816 clrflg: 817 rw_exit(&p->p_reflock); 818 819 if (modgen != module_gen && error == ENOEXEC) { 820 modgen = module_gen; 821 exec_autoload(); 822 goto retry; 823 } 824 825 SDT_PROBE(proc,,,exec_failure, error, 0, 0, 0, 0); 826 return error; 827 } 828 829 static int 830 execve_dovmcmds(struct lwp *l, struct execve_data * restrict data) 831 { 832 struct exec_package * const epp = &data->ed_pack; 833 struct proc *p = l->l_proc; 834 struct exec_vmcmd *base_vcp; 835 int error = 0; 836 size_t i; 837 838 /* record proc's vnode, for use by procfs and others */ 839 if (p->p_textvp) 840 vrele(p->p_textvp); 841 vref(epp->ep_vp); 842 p->p_textvp = epp->ep_vp; 843 844 /* create the new process's VM space by running the vmcmds */ 845 KASSERTMSG(epp->ep_vmcmds.evs_used != 0, "%s: no vmcmds", __func__); 846 847 DUMPVMCMDS(epp, 0, 0); 848 849 base_vcp = NULL; 850 851 for (i = 0; i < epp->ep_vmcmds.evs_used && !error; i++) { 852 struct exec_vmcmd *vcp; 853 854 vcp = &epp->ep_vmcmds.evs_cmds[i]; 855 if (vcp->ev_flags & VMCMD_RELATIVE) { 856 KASSERTMSG(base_vcp != NULL, 857 "%s: relative vmcmd with no base", __func__); 858 KASSERTMSG((vcp->ev_flags & VMCMD_BASE) == 0, 859 "%s: illegal base & relative vmcmd", __func__); 860 vcp->ev_addr += base_vcp->ev_addr; 861 } 862 error = (*vcp->ev_proc)(l, vcp); 863 if (error) 864 DUMPVMCMDS(epp, i, error); 865 if (vcp->ev_flags & VMCMD_BASE) 866 base_vcp = vcp; 867 } 868 869 /* free the vmspace-creation commands, and release their references */ 870 kill_vmcmds(&epp->ep_vmcmds); 871 872 vn_lock(epp->ep_vp, LK_EXCLUSIVE | LK_RETRY); 873 VOP_CLOSE(epp->ep_vp, FREAD, l->l_cred); 874 vput(epp->ep_vp); 875 876 /* if an error happened, deallocate and punt */ 877 if (error != 0) { 878 DPRINTF(("%s: vmcmd %zu failed: %d\n", __func__, i - 1, error)); 879 } 880 return error; 881 } 882 883 static void 884 execve_free_data(struct execve_data *data) 885 { 886 struct exec_package * const epp = &data->ed_pack; 887 888 /* free the vmspace-creation commands, and release their references */ 889 kill_vmcmds(&epp->ep_vmcmds); 890 /* kill any opened file descriptor, if necessary */ 891 if (epp->ep_flags & EXEC_HASFD) { 892 epp->ep_flags &= ~EXEC_HASFD; 893 fd_close(epp->ep_fd); 894 } 895 896 /* close and put the exec'd file */ 897 vn_lock(epp->ep_vp, LK_EXCLUSIVE | LK_RETRY); 898 VOP_CLOSE(epp->ep_vp, FREAD, curlwp->l_cred); 899 vput(epp->ep_vp); 900 pool_put(&exec_pool, data->ed_argp); 901 902 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 903 if (epp->ep_emul_root != NULL) 904 vrele(epp->ep_emul_root); 905 if (epp->ep_interp != NULL) 906 vrele(epp->ep_interp); 907 908 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 909 pathbuf_destroy(data->ed_pathbuf); 910 PNBUF_PUT(data->ed_resolvedpathbuf); 911 } 912 913 static void 914 pathexec(struct exec_package *epp, struct proc *p, const char *pathstring) 915 { 916 const char *commandname; 917 size_t commandlen; 918 char *path; 919 920 /* set command name & other accounting info */ 921 commandname = strrchr(epp->ep_resolvedname, '/'); 922 if (commandname != NULL) { 923 commandname++; 924 } else { 925 commandname = epp->ep_resolvedname; 926 } 927 commandlen = min(strlen(commandname), MAXCOMLEN); 928 (void)memcpy(p->p_comm, commandname, commandlen); 929 p->p_comm[commandlen] = '\0'; 930 931 932 /* 933 * If the path starts with /, we don't need to do any work. 934 * This handles the majority of the cases. 935 * In the future perhaps we could canonicalize it? 936 */ 937 if (pathstring[0] == '/') { 938 path = PNBUF_GET(); 939 (void)strlcpy(path, pathstring, MAXPATHLEN); 940 epp->ep_path = path; 941 } else 942 epp->ep_path = NULL; 943 } 944 945 /* XXX elsewhere */ 946 static int 947 credexec(struct lwp *l, struct vattr *attr) 948 { 949 struct proc *p = l->l_proc; 950 int error; 951 952 /* 953 * Deal with set[ug]id. MNT_NOSUID has already been used to disable 954 * s[ug]id. It's OK to check for PSL_TRACED here as we have blocked 955 * out additional references on the process for the moment. 956 */ 957 if ((p->p_slflag & PSL_TRACED) == 0 && 958 959 (((attr->va_mode & S_ISUID) != 0 && 960 kauth_cred_geteuid(l->l_cred) != attr->va_uid) || 961 962 ((attr->va_mode & S_ISGID) != 0 && 963 kauth_cred_getegid(l->l_cred) != attr->va_gid))) { 964 /* 965 * Mark the process as SUGID before we do 966 * anything that might block. 967 */ 968 proc_crmod_enter(); 969 proc_crmod_leave(NULL, NULL, true); 970 971 /* Make sure file descriptors 0..2 are in use. */ 972 if ((error = fd_checkstd()) != 0) { 973 DPRINTF(("%s: fdcheckstd failed %d\n", 974 __func__, error)); 975 return error; 976 } 977 978 /* 979 * Copy the credential so other references don't see our 980 * changes. 981 */ 982 l->l_cred = kauth_cred_copy(l->l_cred); 983 #ifdef KTRACE 984 /* 985 * If the persistent trace flag isn't set, turn off. 986 */ 987 if (p->p_tracep) { 988 mutex_enter(&ktrace_lock); 989 if (!(p->p_traceflag & KTRFAC_PERSISTENT)) 990 ktrderef(p); 991 mutex_exit(&ktrace_lock); 992 } 993 #endif 994 if (attr->va_mode & S_ISUID) 995 kauth_cred_seteuid(l->l_cred, attr->va_uid); 996 if (attr->va_mode & S_ISGID) 997 kauth_cred_setegid(l->l_cred, attr->va_gid); 998 } else { 999 if (kauth_cred_geteuid(l->l_cred) == 1000 kauth_cred_getuid(l->l_cred) && 1001 kauth_cred_getegid(l->l_cred) == 1002 kauth_cred_getgid(l->l_cred)) 1003 p->p_flag &= ~PK_SUGID; 1004 } 1005 1006 /* 1007 * Copy the credential so other references don't see our changes. 1008 * Test to see if this is necessary first, since in the common case 1009 * we won't need a private reference. 1010 */ 1011 if (kauth_cred_geteuid(l->l_cred) != kauth_cred_getsvuid(l->l_cred) || 1012 kauth_cred_getegid(l->l_cred) != kauth_cred_getsvgid(l->l_cred)) { 1013 l->l_cred = kauth_cred_copy(l->l_cred); 1014 kauth_cred_setsvuid(l->l_cred, kauth_cred_geteuid(l->l_cred)); 1015 kauth_cred_setsvgid(l->l_cred, kauth_cred_getegid(l->l_cred)); 1016 } 1017 1018 /* Update the master credentials. */ 1019 if (l->l_cred != p->p_cred) { 1020 kauth_cred_t ocred; 1021 1022 kauth_cred_hold(l->l_cred); 1023 mutex_enter(p->p_lock); 1024 ocred = p->p_cred; 1025 p->p_cred = l->l_cred; 1026 mutex_exit(p->p_lock); 1027 kauth_cred_free(ocred); 1028 } 1029 1030 return 0; 1031 } 1032 1033 static void 1034 emulexec(struct lwp *l, struct exec_package *epp) 1035 { 1036 struct proc *p = l->l_proc; 1037 1038 /* The emulation root will usually have been found when we looked 1039 * for the elf interpreter (or similar), if not look now. */ 1040 if (epp->ep_esch->es_emul->e_path != NULL && 1041 epp->ep_emul_root == NULL) 1042 emul_find_root(l, epp); 1043 1044 /* Any old emulation root got removed by fdcloseexec */ 1045 rw_enter(&p->p_cwdi->cwdi_lock, RW_WRITER); 1046 p->p_cwdi->cwdi_edir = epp->ep_emul_root; 1047 rw_exit(&p->p_cwdi->cwdi_lock); 1048 epp->ep_emul_root = NULL; 1049 if (epp->ep_interp != NULL) 1050 vrele(epp->ep_interp); 1051 1052 /* 1053 * Call emulation specific exec hook. This can setup per-process 1054 * p->p_emuldata or do any other per-process stuff an emulation needs. 1055 * 1056 * If we are executing process of different emulation than the 1057 * original forked process, call e_proc_exit() of the old emulation 1058 * first, then e_proc_exec() of new emulation. If the emulation is 1059 * same, the exec hook code should deallocate any old emulation 1060 * resources held previously by this process. 1061 */ 1062 if (p->p_emul && p->p_emul->e_proc_exit 1063 && p->p_emul != epp->ep_esch->es_emul) 1064 (*p->p_emul->e_proc_exit)(p); 1065 1066 /* 1067 * This is now LWP 1. 1068 */ 1069 /* XXX elsewhere */ 1070 mutex_enter(p->p_lock); 1071 p->p_nlwpid = 1; 1072 l->l_lid = 1; 1073 mutex_exit(p->p_lock); 1074 1075 /* 1076 * Call exec hook. Emulation code may NOT store reference to anything 1077 * from &pack. 1078 */ 1079 if (epp->ep_esch->es_emul->e_proc_exec) 1080 (*epp->ep_esch->es_emul->e_proc_exec)(p, epp); 1081 1082 /* update p_emul, the old value is no longer needed */ 1083 p->p_emul = epp->ep_esch->es_emul; 1084 1085 /* ...and the same for p_execsw */ 1086 p->p_execsw = epp->ep_esch; 1087 1088 #ifdef __HAVE_SYSCALL_INTERN 1089 (*p->p_emul->e_syscall_intern)(p); 1090 #endif 1091 ktremul(); 1092 } 1093 1094 static int 1095 execve_runproc(struct lwp *l, struct execve_data * restrict data, 1096 bool no_local_exec_lock, bool is_spawn) 1097 { 1098 struct exec_package * const epp = &data->ed_pack; 1099 int error = 0; 1100 struct proc *p; 1101 1102 /* 1103 * In case of a posix_spawn operation, the child doing the exec 1104 * might not hold the reader lock on exec_lock, but the parent 1105 * will do this instead. 1106 */ 1107 KASSERT(no_local_exec_lock || rw_lock_held(&exec_lock)); 1108 KASSERT(!no_local_exec_lock || is_spawn); 1109 KASSERT(data != NULL); 1110 1111 p = l->l_proc; 1112 1113 /* Get rid of other LWPs. */ 1114 if (p->p_nlwps > 1) { 1115 mutex_enter(p->p_lock); 1116 exit_lwps(l); 1117 mutex_exit(p->p_lock); 1118 } 1119 KDASSERT(p->p_nlwps == 1); 1120 1121 /* Destroy any lwpctl info. */ 1122 if (p->p_lwpctl != NULL) 1123 lwp_ctl_exit(); 1124 1125 /* Remove POSIX timers */ 1126 timers_free(p, TIMERS_POSIX); 1127 1128 /* Set the PaX flags. */ 1129 p->p_pax = epp->ep_pax_flags; 1130 1131 /* 1132 * Do whatever is necessary to prepare the address space 1133 * for remapping. Note that this might replace the current 1134 * vmspace with another! 1135 */ 1136 if (is_spawn) 1137 uvmspace_spawn(l, epp->ep_vm_minaddr, 1138 epp->ep_vm_maxaddr, 1139 epp->ep_flags & EXEC_TOPDOWN_VM); 1140 else 1141 uvmspace_exec(l, epp->ep_vm_minaddr, 1142 epp->ep_vm_maxaddr, 1143 epp->ep_flags & EXEC_TOPDOWN_VM); 1144 1145 struct vmspace *vm; 1146 vm = p->p_vmspace; 1147 vm->vm_taddr = (void *)epp->ep_taddr; 1148 vm->vm_tsize = btoc(epp->ep_tsize); 1149 vm->vm_daddr = (void*)epp->ep_daddr; 1150 vm->vm_dsize = btoc(epp->ep_dsize); 1151 vm->vm_ssize = btoc(epp->ep_ssize); 1152 vm->vm_issize = 0; 1153 vm->vm_maxsaddr = (void *)epp->ep_maxsaddr; 1154 vm->vm_minsaddr = (void *)epp->ep_minsaddr; 1155 1156 #ifdef PAX_ASLR 1157 pax_aslr_init_vm(l, vm); 1158 #endif /* PAX_ASLR */ 1159 1160 /* Now map address space. */ 1161 error = execve_dovmcmds(l, data); 1162 if (error != 0) 1163 goto exec_abort; 1164 1165 pathexec(epp, p, data->ed_pathstring); 1166 1167 char * const newstack = STACK_GROW(vm->vm_minsaddr, epp->ep_ssize); 1168 1169 error = copyoutargs(data, l, newstack); 1170 if (error != 0) 1171 goto exec_abort; 1172 1173 cwdexec(p); 1174 fd_closeexec(); /* handle close on exec */ 1175 1176 if (__predict_false(ktrace_on)) 1177 fd_ktrexecfd(); 1178 1179 execsigs(p); /* reset catched signals */ 1180 1181 mutex_enter(p->p_lock); 1182 l->l_ctxlink = NULL; /* reset ucontext link */ 1183 p->p_acflag &= ~AFORK; 1184 p->p_flag |= PK_EXEC; 1185 mutex_exit(p->p_lock); 1186 1187 /* 1188 * Stop profiling. 1189 */ 1190 if ((p->p_stflag & PST_PROFIL) != 0) { 1191 mutex_spin_enter(&p->p_stmutex); 1192 stopprofclock(p); 1193 mutex_spin_exit(&p->p_stmutex); 1194 } 1195 1196 /* 1197 * It's OK to test PL_PPWAIT unlocked here, as other LWPs have 1198 * exited and exec()/exit() are the only places it will be cleared. 1199 */ 1200 if ((p->p_lflag & PL_PPWAIT) != 0) { 1201 #if 0 1202 lwp_t *lp; 1203 1204 mutex_enter(proc_lock); 1205 lp = p->p_vforklwp; 1206 p->p_vforklwp = NULL; 1207 1208 l->l_lwpctl = NULL; /* was on loan from blocked parent */ 1209 p->p_lflag &= ~PL_PPWAIT; 1210 1211 lp->l_pflag &= ~LP_VFORKWAIT; /* XXX */ 1212 cv_broadcast(&lp->l_waitcv); 1213 mutex_exit(proc_lock); 1214 #else 1215 mutex_enter(proc_lock); 1216 l->l_lwpctl = NULL; /* was on loan from blocked parent */ 1217 p->p_lflag &= ~PL_PPWAIT; 1218 cv_broadcast(&p->p_pptr->p_waitcv); 1219 mutex_exit(proc_lock); 1220 #endif 1221 } 1222 1223 error = credexec(l, &data->ed_attr); 1224 if (error) 1225 goto exec_abort; 1226 1227 #if defined(__HAVE_RAS) 1228 /* 1229 * Remove all RASs from the address space. 1230 */ 1231 ras_purgeall(); 1232 #endif 1233 1234 doexechooks(p); 1235 1236 /* 1237 * Set initial SP at the top of the stack. 1238 * 1239 * Note that on machines where stack grows up (e.g. hppa), SP points to 1240 * the end of arg/env strings. Userland guesses the address of argc 1241 * via ps_strings::ps_argvstr. 1242 */ 1243 1244 /* Setup new registers and do misc. setup. */ 1245 (*epp->ep_esch->es_emul->e_setregs)(l, epp, (vaddr_t)newstack); 1246 if (epp->ep_esch->es_setregs) 1247 (*epp->ep_esch->es_setregs)(l, epp, (vaddr_t)newstack); 1248 1249 /* Provide a consistent LWP private setting */ 1250 (void)lwp_setprivate(l, NULL); 1251 1252 /* Discard all PCU state; need to start fresh */ 1253 pcu_discard_all(l); 1254 1255 /* map the process's signal trampoline code */ 1256 if ((error = exec_sigcode_map(p, epp->ep_esch->es_emul)) != 0) { 1257 DPRINTF(("%s: map sigcode failed %d\n", __func__, error)); 1258 goto exec_abort; 1259 } 1260 1261 pool_put(&exec_pool, data->ed_argp); 1262 1263 /* notify others that we exec'd */ 1264 KNOTE(&p->p_klist, NOTE_EXEC); 1265 1266 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 1267 1268 SDT_PROBE(proc,,,exec_success, epp->ep_kname, 0, 0, 0, 0); 1269 1270 emulexec(l, epp); 1271 1272 /* Allow new references from the debugger/procfs. */ 1273 rw_exit(&p->p_reflock); 1274 if (!no_local_exec_lock) 1275 rw_exit(&exec_lock); 1276 1277 mutex_enter(proc_lock); 1278 1279 if ((p->p_slflag & (PSL_TRACED|PSL_SYSCALL)) == PSL_TRACED) { 1280 ksiginfo_t ksi; 1281 1282 KSI_INIT_EMPTY(&ksi); 1283 ksi.ksi_signo = SIGTRAP; 1284 ksi.ksi_lid = l->l_lid; 1285 kpsignal(p, &ksi, NULL); 1286 } 1287 1288 if (p->p_sflag & PS_STOPEXEC) { 1289 ksiginfoq_t kq; 1290 1291 KERNEL_UNLOCK_ALL(l, &l->l_biglocks); 1292 p->p_pptr->p_nstopchild++; 1293 p->p_pptr->p_waited = 0; 1294 mutex_enter(p->p_lock); 1295 ksiginfo_queue_init(&kq); 1296 sigclearall(p, &contsigmask, &kq); 1297 lwp_lock(l); 1298 l->l_stat = LSSTOP; 1299 p->p_stat = SSTOP; 1300 p->p_nrlwps--; 1301 lwp_unlock(l); 1302 mutex_exit(p->p_lock); 1303 mutex_exit(proc_lock); 1304 lwp_lock(l); 1305 mi_switch(l); 1306 ksiginfo_queue_drain(&kq); 1307 KERNEL_LOCK(l->l_biglocks, l); 1308 } else { 1309 mutex_exit(proc_lock); 1310 } 1311 1312 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 1313 pathbuf_destroy(data->ed_pathbuf); 1314 PNBUF_PUT(data->ed_resolvedpathbuf); 1315 DPRINTF(("%s finished\n", __func__)); 1316 return EJUSTRETURN; 1317 1318 exec_abort: 1319 SDT_PROBE(proc,,,exec_failure, error, 0, 0, 0, 0); 1320 rw_exit(&p->p_reflock); 1321 if (!no_local_exec_lock) 1322 rw_exit(&exec_lock); 1323 1324 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 1325 pathbuf_destroy(data->ed_pathbuf); 1326 PNBUF_PUT(data->ed_resolvedpathbuf); 1327 1328 /* 1329 * the old process doesn't exist anymore. exit gracefully. 1330 * get rid of the (new) address space we have created, if any, get rid 1331 * of our namei data and vnode, and exit noting failure 1332 */ 1333 uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, 1334 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); 1335 1336 exec_free_emul_arg(epp); 1337 pool_put(&exec_pool, data->ed_argp); 1338 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 1339 if (epp->ep_emul_root != NULL) 1340 vrele(epp->ep_emul_root); 1341 if (epp->ep_interp != NULL) 1342 vrele(epp->ep_interp); 1343 1344 /* Acquire the sched-state mutex (exit1() will release it). */ 1345 if (!is_spawn) { 1346 mutex_enter(p->p_lock); 1347 exit1(l, W_EXITCODE(error, SIGABRT)); 1348 } 1349 1350 return error; 1351 } 1352 1353 int 1354 execve1(struct lwp *l, const char *path, char * const *args, 1355 char * const *envs, execve_fetch_element_t fetch_element) 1356 { 1357 struct execve_data data; 1358 int error; 1359 1360 error = execve_loadvm(l, path, args, envs, fetch_element, &data); 1361 if (error) 1362 return error; 1363 error = execve_runproc(l, &data, false, false); 1364 return error; 1365 } 1366 1367 static size_t 1368 fromptrsz(const struct exec_package *epp) 1369 { 1370 return (epp->ep_flags & EXEC_FROM32) ? sizeof(int) : sizeof(char *); 1371 } 1372 1373 static size_t 1374 ptrsz(const struct exec_package *epp) 1375 { 1376 return (epp->ep_flags & EXEC_32) ? sizeof(int) : sizeof(char *); 1377 } 1378 1379 static size_t 1380 calcargs(struct execve_data * restrict data, const size_t argenvstrlen) 1381 { 1382 struct exec_package * const epp = &data->ed_pack; 1383 1384 const size_t nargenvptrs = 1385 1 + /* long argc */ 1386 data->ed_argc + /* char *argv[] */ 1387 1 + /* \0 */ 1388 data->ed_envc + /* char *env[] */ 1389 1 + /* \0 */ 1390 epp->ep_esch->es_arglen; /* auxinfo */ 1391 1392 return (nargenvptrs * ptrsz(epp)) + argenvstrlen; 1393 } 1394 1395 static size_t 1396 calcstack(struct execve_data * restrict data, const size_t gaplen) 1397 { 1398 struct exec_package * const epp = &data->ed_pack; 1399 1400 data->ed_szsigcode = epp->ep_esch->es_emul->e_esigcode - 1401 epp->ep_esch->es_emul->e_sigcode; 1402 1403 data->ed_ps_strings_sz = (epp->ep_flags & EXEC_32) ? 1404 sizeof(struct ps_strings32) : sizeof(struct ps_strings); 1405 1406 const size_t sigcode_psstr_sz = 1407 data->ed_szsigcode + /* sigcode */ 1408 data->ed_ps_strings_sz + /* ps_strings */ 1409 STACK_PTHREADSPACE; /* pthread space */ 1410 1411 const size_t stacklen = 1412 data->ed_argslen + 1413 gaplen + 1414 sigcode_psstr_sz; 1415 1416 /* make the stack "safely" aligned */ 1417 return STACK_LEN_ALIGN(stacklen, STACK_ALIGNBYTES); 1418 } 1419 1420 static int 1421 copyoutargs(struct execve_data * restrict data, struct lwp *l, 1422 char * const newstack) 1423 { 1424 struct exec_package * const epp = &data->ed_pack; 1425 struct proc *p = l->l_proc; 1426 int error; 1427 1428 /* remember information about the process */ 1429 data->ed_arginfo.ps_nargvstr = data->ed_argc; 1430 data->ed_arginfo.ps_nenvstr = data->ed_envc; 1431 1432 /* 1433 * Allocate the stack address passed to the newly execve()'ed process. 1434 * 1435 * The new stack address will be set to the SP (stack pointer) register 1436 * in setregs(). 1437 */ 1438 1439 char *newargs = STACK_ALLOC( 1440 STACK_SHRINK(newstack, data->ed_argslen), data->ed_argslen); 1441 1442 error = (*epp->ep_esch->es_copyargs)(l, epp, 1443 &data->ed_arginfo, &newargs, data->ed_argp); 1444 1445 if (epp->ep_path) { 1446 PNBUF_PUT(epp->ep_path); 1447 epp->ep_path = NULL; 1448 } 1449 if (error) { 1450 DPRINTF(("%s: copyargs failed %d\n", __func__, error)); 1451 return error; 1452 } 1453 1454 error = copyoutpsstrs(data, p); 1455 if (error != 0) 1456 return error; 1457 1458 return 0; 1459 } 1460 1461 static int 1462 copyoutpsstrs(struct execve_data * restrict data, struct proc *p) 1463 { 1464 struct exec_package * const epp = &data->ed_pack; 1465 struct ps_strings32 arginfo32; 1466 void *aip; 1467 int error; 1468 1469 /* fill process ps_strings info */ 1470 p->p_psstrp = (vaddr_t)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr, 1471 STACK_PTHREADSPACE), data->ed_ps_strings_sz); 1472 1473 if (epp->ep_flags & EXEC_32) { 1474 aip = &arginfo32; 1475 arginfo32.ps_argvstr = (vaddr_t)data->ed_arginfo.ps_argvstr; 1476 arginfo32.ps_nargvstr = data->ed_arginfo.ps_nargvstr; 1477 arginfo32.ps_envstr = (vaddr_t)data->ed_arginfo.ps_envstr; 1478 arginfo32.ps_nenvstr = data->ed_arginfo.ps_nenvstr; 1479 } else 1480 aip = &data->ed_arginfo; 1481 1482 /* copy out the process's ps_strings structure */ 1483 if ((error = copyout(aip, (void *)p->p_psstrp, data->ed_ps_strings_sz)) 1484 != 0) { 1485 DPRINTF(("%s: ps_strings copyout %p->%p size %zu failed\n", 1486 __func__, aip, (void *)p->p_psstrp, data->ed_ps_strings_sz)); 1487 return error; 1488 } 1489 1490 return 0; 1491 } 1492 1493 static int 1494 copyinargs(struct execve_data * restrict data, char * const *args, 1495 char * const *envs, execve_fetch_element_t fetch_element, char **dpp) 1496 { 1497 struct exec_package * const epp = &data->ed_pack; 1498 char *dp; 1499 size_t i; 1500 int error; 1501 1502 dp = *dpp; 1503 1504 data->ed_argc = 0; 1505 1506 /* copy the fake args list, if there's one, freeing it as we go */ 1507 if (epp->ep_flags & EXEC_HASARGL) { 1508 struct exec_fakearg *fa = epp->ep_fa; 1509 1510 while (fa->fa_arg != NULL) { 1511 const size_t maxlen = ARG_MAX - (dp - data->ed_argp); 1512 size_t len; 1513 1514 len = strlcpy(dp, fa->fa_arg, maxlen); 1515 /* Count NUL into len. */ 1516 if (len < maxlen) 1517 len++; 1518 else { 1519 while (fa->fa_arg != NULL) { 1520 kmem_free(fa->fa_arg, fa->fa_len); 1521 fa++; 1522 } 1523 kmem_free(epp->ep_fa, epp->ep_fa_len); 1524 epp->ep_flags &= ~EXEC_HASARGL; 1525 return E2BIG; 1526 } 1527 ktrexecarg(fa->fa_arg, len - 1); 1528 dp += len; 1529 1530 kmem_free(fa->fa_arg, fa->fa_len); 1531 fa++; 1532 data->ed_argc++; 1533 } 1534 kmem_free(epp->ep_fa, epp->ep_fa_len); 1535 epp->ep_flags &= ~EXEC_HASARGL; 1536 } 1537 1538 /* 1539 * Read and count argument strings from user. 1540 */ 1541 1542 if (args == NULL) { 1543 DPRINTF(("%s: null args\n", __func__)); 1544 return EINVAL; 1545 } 1546 if (epp->ep_flags & EXEC_SKIPARG) 1547 args = (const void *)((const char *)args + fromptrsz(epp)); 1548 i = 0; 1549 error = copyinargstrs(data, args, fetch_element, &dp, &i, ktr_execarg); 1550 if (error != 0) { 1551 DPRINTF(("%s: copyin arg %d\n", __func__, error)); 1552 return error; 1553 } 1554 data->ed_argc += i; 1555 1556 /* 1557 * Read and count environment strings from user. 1558 */ 1559 1560 data->ed_envc = 0; 1561 /* environment need not be there */ 1562 if (envs == NULL) 1563 goto done; 1564 i = 0; 1565 error = copyinargstrs(data, envs, fetch_element, &dp, &i, ktr_execenv); 1566 if (error != 0) { 1567 DPRINTF(("%s: copyin env %d\n", __func__, error)); 1568 return error; 1569 } 1570 data->ed_envc += i; 1571 1572 done: 1573 *dpp = dp; 1574 1575 return 0; 1576 } 1577 1578 static int 1579 copyinargstrs(struct execve_data * restrict data, char * const *strs, 1580 execve_fetch_element_t fetch_element, char **dpp, size_t *ip, 1581 void (*ktr)(const void *, size_t)) 1582 { 1583 char *dp, *sp; 1584 size_t i; 1585 int error; 1586 1587 dp = *dpp; 1588 1589 i = 0; 1590 while (1) { 1591 const size_t maxlen = ARG_MAX - (dp - data->ed_argp); 1592 size_t len; 1593 1594 if ((error = (*fetch_element)(strs, i, &sp)) != 0) { 1595 return error; 1596 } 1597 if (!sp) 1598 break; 1599 if ((error = copyinstr(sp, dp, maxlen, &len)) != 0) { 1600 if (error == ENAMETOOLONG) 1601 error = E2BIG; 1602 return error; 1603 } 1604 if (__predict_false(ktrace_on)) 1605 (*ktr)(dp, len - 1); 1606 dp += len; 1607 i++; 1608 } 1609 1610 *dpp = dp; 1611 *ip = i; 1612 1613 return 0; 1614 } 1615 1616 /* 1617 * Copy argv and env strings from kernel buffer (argp) to the new stack. 1618 * Those strings are located just after auxinfo. 1619 */ 1620 int 1621 copyargs(struct lwp *l, struct exec_package *pack, struct ps_strings *arginfo, 1622 char **stackp, void *argp) 1623 { 1624 char **cpp, *dp, *sp; 1625 size_t len; 1626 void *nullp; 1627 long argc, envc; 1628 int error; 1629 1630 cpp = (char **)*stackp; 1631 nullp = NULL; 1632 argc = arginfo->ps_nargvstr; 1633 envc = arginfo->ps_nenvstr; 1634 1635 /* argc on stack is long */ 1636 CTASSERT(sizeof(*cpp) == sizeof(argc)); 1637 1638 dp = (char *)(cpp + 1639 1 + /* long argc */ 1640 argc + /* char *argv[] */ 1641 1 + /* \0 */ 1642 envc + /* char *env[] */ 1643 1 + /* \0 */ 1644 /* XXX auxinfo multiplied by ptr size? */ 1645 pack->ep_esch->es_arglen); /* auxinfo */ 1646 sp = argp; 1647 1648 if ((error = copyout(&argc, cpp++, sizeof(argc))) != 0) { 1649 COPYPRINTF("", cpp - 1, sizeof(argc)); 1650 return error; 1651 } 1652 1653 /* XXX don't copy them out, remap them! */ 1654 arginfo->ps_argvstr = cpp; /* remember location of argv for later */ 1655 1656 for (; --argc >= 0; sp += len, dp += len) { 1657 if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0) { 1658 COPYPRINTF("", cpp - 1, sizeof(dp)); 1659 return error; 1660 } 1661 if ((error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0) { 1662 COPYPRINTF("str", dp, (size_t)ARG_MAX); 1663 return error; 1664 } 1665 } 1666 1667 if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0) { 1668 COPYPRINTF("", cpp - 1, sizeof(nullp)); 1669 return error; 1670 } 1671 1672 arginfo->ps_envstr = cpp; /* remember location of envp for later */ 1673 1674 for (; --envc >= 0; sp += len, dp += len) { 1675 if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0) { 1676 COPYPRINTF("", cpp - 1, sizeof(dp)); 1677 return error; 1678 } 1679 if ((error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0) { 1680 COPYPRINTF("str", dp, (size_t)ARG_MAX); 1681 return error; 1682 } 1683 1684 } 1685 1686 if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0) { 1687 COPYPRINTF("", cpp - 1, sizeof(nullp)); 1688 return error; 1689 } 1690 1691 *stackp = (char *)cpp; 1692 return 0; 1693 } 1694 1695 1696 /* 1697 * Add execsw[] entries. 1698 */ 1699 int 1700 exec_add(struct execsw *esp, int count) 1701 { 1702 struct exec_entry *it; 1703 int i; 1704 1705 if (count == 0) { 1706 return 0; 1707 } 1708 1709 /* Check for duplicates. */ 1710 rw_enter(&exec_lock, RW_WRITER); 1711 for (i = 0; i < count; i++) { 1712 LIST_FOREACH(it, &ex_head, ex_list) { 1713 /* assume unique (makecmds, probe_func, emulation) */ 1714 if (it->ex_sw->es_makecmds == esp[i].es_makecmds && 1715 it->ex_sw->u.elf_probe_func == 1716 esp[i].u.elf_probe_func && 1717 it->ex_sw->es_emul == esp[i].es_emul) { 1718 rw_exit(&exec_lock); 1719 return EEXIST; 1720 } 1721 } 1722 } 1723 1724 /* Allocate new entries. */ 1725 for (i = 0; i < count; i++) { 1726 it = kmem_alloc(sizeof(*it), KM_SLEEP); 1727 it->ex_sw = &esp[i]; 1728 LIST_INSERT_HEAD(&ex_head, it, ex_list); 1729 } 1730 1731 /* update execsw[] */ 1732 exec_init(0); 1733 rw_exit(&exec_lock); 1734 return 0; 1735 } 1736 1737 /* 1738 * Remove execsw[] entry. 1739 */ 1740 int 1741 exec_remove(struct execsw *esp, int count) 1742 { 1743 struct exec_entry *it, *next; 1744 int i; 1745 const struct proclist_desc *pd; 1746 proc_t *p; 1747 1748 if (count == 0) { 1749 return 0; 1750 } 1751 1752 /* Abort if any are busy. */ 1753 rw_enter(&exec_lock, RW_WRITER); 1754 for (i = 0; i < count; i++) { 1755 mutex_enter(proc_lock); 1756 for (pd = proclists; pd->pd_list != NULL; pd++) { 1757 PROCLIST_FOREACH(p, pd->pd_list) { 1758 if (p->p_execsw == &esp[i]) { 1759 mutex_exit(proc_lock); 1760 rw_exit(&exec_lock); 1761 return EBUSY; 1762 } 1763 } 1764 } 1765 mutex_exit(proc_lock); 1766 } 1767 1768 /* None are busy, so remove them all. */ 1769 for (i = 0; i < count; i++) { 1770 for (it = LIST_FIRST(&ex_head); it != NULL; it = next) { 1771 next = LIST_NEXT(it, ex_list); 1772 if (it->ex_sw == &esp[i]) { 1773 LIST_REMOVE(it, ex_list); 1774 kmem_free(it, sizeof(*it)); 1775 break; 1776 } 1777 } 1778 } 1779 1780 /* update execsw[] */ 1781 exec_init(0); 1782 rw_exit(&exec_lock); 1783 return 0; 1784 } 1785 1786 /* 1787 * Initialize exec structures. If init_boot is true, also does necessary 1788 * one-time initialization (it's called from main() that way). 1789 * Once system is multiuser, this should be called with exec_lock held, 1790 * i.e. via exec_{add|remove}(). 1791 */ 1792 int 1793 exec_init(int init_boot) 1794 { 1795 const struct execsw **sw; 1796 struct exec_entry *ex; 1797 SLIST_HEAD(,exec_entry) first; 1798 SLIST_HEAD(,exec_entry) any; 1799 SLIST_HEAD(,exec_entry) last; 1800 int i, sz; 1801 1802 if (init_boot) { 1803 /* do one-time initializations */ 1804 rw_init(&exec_lock); 1805 mutex_init(&sigobject_lock, MUTEX_DEFAULT, IPL_NONE); 1806 pool_init(&exec_pool, NCARGS, 0, 0, PR_NOALIGN|PR_NOTOUCH, 1807 "execargs", &exec_palloc, IPL_NONE); 1808 pool_sethardlimit(&exec_pool, maxexec, "should not happen", 0); 1809 } else { 1810 KASSERT(rw_write_held(&exec_lock)); 1811 } 1812 1813 /* Sort each entry onto the appropriate queue. */ 1814 SLIST_INIT(&first); 1815 SLIST_INIT(&any); 1816 SLIST_INIT(&last); 1817 sz = 0; 1818 LIST_FOREACH(ex, &ex_head, ex_list) { 1819 switch(ex->ex_sw->es_prio) { 1820 case EXECSW_PRIO_FIRST: 1821 SLIST_INSERT_HEAD(&first, ex, ex_slist); 1822 break; 1823 case EXECSW_PRIO_ANY: 1824 SLIST_INSERT_HEAD(&any, ex, ex_slist); 1825 break; 1826 case EXECSW_PRIO_LAST: 1827 SLIST_INSERT_HEAD(&last, ex, ex_slist); 1828 break; 1829 default: 1830 panic("%s", __func__); 1831 break; 1832 } 1833 sz++; 1834 } 1835 1836 /* 1837 * Create new execsw[]. Ensure we do not try a zero-sized 1838 * allocation. 1839 */ 1840 sw = kmem_alloc(sz * sizeof(struct execsw *) + 1, KM_SLEEP); 1841 i = 0; 1842 SLIST_FOREACH(ex, &first, ex_slist) { 1843 sw[i++] = ex->ex_sw; 1844 } 1845 SLIST_FOREACH(ex, &any, ex_slist) { 1846 sw[i++] = ex->ex_sw; 1847 } 1848 SLIST_FOREACH(ex, &last, ex_slist) { 1849 sw[i++] = ex->ex_sw; 1850 } 1851 1852 /* Replace old execsw[] and free used memory. */ 1853 if (execsw != NULL) { 1854 kmem_free(__UNCONST(execsw), 1855 nexecs * sizeof(struct execsw *) + 1); 1856 } 1857 execsw = sw; 1858 nexecs = sz; 1859 1860 /* Figure out the maximum size of an exec header. */ 1861 exec_maxhdrsz = sizeof(int); 1862 for (i = 0; i < nexecs; i++) { 1863 if (execsw[i]->es_hdrsz > exec_maxhdrsz) 1864 exec_maxhdrsz = execsw[i]->es_hdrsz; 1865 } 1866 1867 return 0; 1868 } 1869 1870 static int 1871 exec_sigcode_map(struct proc *p, const struct emul *e) 1872 { 1873 vaddr_t va; 1874 vsize_t sz; 1875 int error; 1876 struct uvm_object *uobj; 1877 1878 sz = (vaddr_t)e->e_esigcode - (vaddr_t)e->e_sigcode; 1879 1880 if (e->e_sigobject == NULL || sz == 0) { 1881 return 0; 1882 } 1883 1884 /* 1885 * If we don't have a sigobject for this emulation, create one. 1886 * 1887 * sigobject is an anonymous memory object (just like SYSV shared 1888 * memory) that we keep a permanent reference to and that we map 1889 * in all processes that need this sigcode. The creation is simple, 1890 * we create an object, add a permanent reference to it, map it in 1891 * kernel space, copy out the sigcode to it and unmap it. 1892 * We map it with PROT_READ|PROT_EXEC into the process just 1893 * the way sys_mmap() would map it. 1894 */ 1895 1896 uobj = *e->e_sigobject; 1897 if (uobj == NULL) { 1898 mutex_enter(&sigobject_lock); 1899 if ((uobj = *e->e_sigobject) == NULL) { 1900 uobj = uao_create(sz, 0); 1901 (*uobj->pgops->pgo_reference)(uobj); 1902 va = vm_map_min(kernel_map); 1903 if ((error = uvm_map(kernel_map, &va, round_page(sz), 1904 uobj, 0, 0, 1905 UVM_MAPFLAG(UVM_PROT_RW, UVM_PROT_RW, 1906 UVM_INH_SHARE, UVM_ADV_RANDOM, 0)))) { 1907 printf("kernel mapping failed %d\n", error); 1908 (*uobj->pgops->pgo_detach)(uobj); 1909 mutex_exit(&sigobject_lock); 1910 return error; 1911 } 1912 memcpy((void *)va, e->e_sigcode, sz); 1913 #ifdef PMAP_NEED_PROCWR 1914 pmap_procwr(&proc0, va, sz); 1915 #endif 1916 uvm_unmap(kernel_map, va, va + round_page(sz)); 1917 *e->e_sigobject = uobj; 1918 } 1919 mutex_exit(&sigobject_lock); 1920 } 1921 1922 /* Just a hint to uvm_map where to put it. */ 1923 va = e->e_vm_default_addr(p, (vaddr_t)p->p_vmspace->vm_daddr, 1924 round_page(sz)); 1925 1926 #ifdef __alpha__ 1927 /* 1928 * Tru64 puts /sbin/loader at the end of user virtual memory, 1929 * which causes the above calculation to put the sigcode at 1930 * an invalid address. Put it just below the text instead. 1931 */ 1932 if (va == (vaddr_t)vm_map_max(&p->p_vmspace->vm_map)) { 1933 va = (vaddr_t)p->p_vmspace->vm_taddr - round_page(sz); 1934 } 1935 #endif 1936 1937 (*uobj->pgops->pgo_reference)(uobj); 1938 error = uvm_map(&p->p_vmspace->vm_map, &va, round_page(sz), 1939 uobj, 0, 0, 1940 UVM_MAPFLAG(UVM_PROT_RX, UVM_PROT_RX, UVM_INH_SHARE, 1941 UVM_ADV_RANDOM, 0)); 1942 if (error) { 1943 DPRINTF(("%s, %d: map %p " 1944 "uvm_map %#"PRIxVSIZE"@%#"PRIxVADDR" failed %d\n", 1945 __func__, __LINE__, &p->p_vmspace->vm_map, round_page(sz), 1946 va, error)); 1947 (*uobj->pgops->pgo_detach)(uobj); 1948 return error; 1949 } 1950 p->p_sigctx.ps_sigcode = (void *)va; 1951 return 0; 1952 } 1953 1954 /* 1955 * Release a refcount on spawn_exec_data and destroy memory, if this 1956 * was the last one. 1957 */ 1958 static void 1959 spawn_exec_data_release(struct spawn_exec_data *data) 1960 { 1961 if (atomic_dec_32_nv(&data->sed_refcnt) != 0) 1962 return; 1963 1964 cv_destroy(&data->sed_cv_child_ready); 1965 mutex_destroy(&data->sed_mtx_child); 1966 1967 if (data->sed_actions) 1968 posix_spawn_fa_free(data->sed_actions, 1969 data->sed_actions->len); 1970 if (data->sed_attrs) 1971 kmem_free(data->sed_attrs, 1972 sizeof(*data->sed_attrs)); 1973 kmem_free(data, sizeof(*data)); 1974 } 1975 1976 /* 1977 * A child lwp of a posix_spawn operation starts here and ends up in 1978 * cpu_spawn_return, dealing with all filedescriptor and scheduler 1979 * manipulations in between. 1980 * The parent waits for the child, as it is not clear whether the child 1981 * will be able to acquire its own exec_lock. If it can, the parent can 1982 * be released early and continue running in parallel. If not (or if the 1983 * magic debug flag is passed in the scheduler attribute struct), the 1984 * child rides on the parent's exec lock until it is ready to return to 1985 * to userland - and only then releases the parent. This method loses 1986 * concurrency, but improves error reporting. 1987 */ 1988 static void 1989 spawn_return(void *arg) 1990 { 1991 struct spawn_exec_data *spawn_data = arg; 1992 struct lwp *l = curlwp; 1993 int error, newfd; 1994 size_t i; 1995 const struct posix_spawn_file_actions_entry *fae; 1996 pid_t ppid; 1997 register_t retval; 1998 bool have_reflock; 1999 bool parent_is_waiting = true; 2000 2001 /* 2002 * Check if we can release parent early. 2003 * We either need to have no sed_attrs, or sed_attrs does not 2004 * have POSIX_SPAWN_RETURNERROR or one of the flags, that require 2005 * safe access to the parent proc (passed in sed_parent). 2006 * We then try to get the exec_lock, and only if that works, we can 2007 * release the parent here already. 2008 */ 2009 ppid = spawn_data->sed_parent->p_pid; 2010 if ((!spawn_data->sed_attrs 2011 || (spawn_data->sed_attrs->sa_flags 2012 & (POSIX_SPAWN_RETURNERROR|POSIX_SPAWN_SETPGROUP)) == 0) 2013 && rw_tryenter(&exec_lock, RW_READER)) { 2014 parent_is_waiting = false; 2015 mutex_enter(&spawn_data->sed_mtx_child); 2016 cv_signal(&spawn_data->sed_cv_child_ready); 2017 mutex_exit(&spawn_data->sed_mtx_child); 2018 } 2019 2020 /* don't allow debugger access yet */ 2021 rw_enter(&l->l_proc->p_reflock, RW_WRITER); 2022 have_reflock = true; 2023 2024 error = 0; 2025 /* handle posix_spawn_file_actions */ 2026 if (spawn_data->sed_actions != NULL) { 2027 for (i = 0; i < spawn_data->sed_actions->len; i++) { 2028 fae = &spawn_data->sed_actions->fae[i]; 2029 switch (fae->fae_action) { 2030 case FAE_OPEN: 2031 if (fd_getfile(fae->fae_fildes) != NULL) { 2032 error = fd_close(fae->fae_fildes); 2033 if (error) 2034 break; 2035 } 2036 error = fd_open(fae->fae_path, fae->fae_oflag, 2037 fae->fae_mode, &newfd); 2038 if (error) 2039 break; 2040 if (newfd != fae->fae_fildes) { 2041 error = dodup(l, newfd, 2042 fae->fae_fildes, 0, &retval); 2043 if (fd_getfile(newfd) != NULL) 2044 fd_close(newfd); 2045 } 2046 break; 2047 case FAE_DUP2: 2048 error = dodup(l, fae->fae_fildes, 2049 fae->fae_newfildes, 0, &retval); 2050 break; 2051 case FAE_CLOSE: 2052 if (fd_getfile(fae->fae_fildes) == NULL) { 2053 error = EBADF; 2054 break; 2055 } 2056 error = fd_close(fae->fae_fildes); 2057 break; 2058 } 2059 if (error) 2060 goto report_error; 2061 } 2062 } 2063 2064 /* handle posix_spawnattr */ 2065 if (spawn_data->sed_attrs != NULL) { 2066 int ostat; 2067 struct sigaction sigact; 2068 sigact._sa_u._sa_handler = SIG_DFL; 2069 sigact.sa_flags = 0; 2070 2071 /* 2072 * set state to SSTOP so that this proc can be found by pid. 2073 * see proc_enterprp, do_sched_setparam below 2074 */ 2075 ostat = l->l_proc->p_stat; 2076 l->l_proc->p_stat = SSTOP; 2077 2078 /* Set process group */ 2079 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETPGROUP) { 2080 pid_t mypid = l->l_proc->p_pid, 2081 pgrp = spawn_data->sed_attrs->sa_pgroup; 2082 2083 if (pgrp == 0) 2084 pgrp = mypid; 2085 2086 error = proc_enterpgrp(spawn_data->sed_parent, 2087 mypid, pgrp, false); 2088 if (error) 2089 goto report_error; 2090 } 2091 2092 /* Set scheduler policy */ 2093 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETSCHEDULER) 2094 error = do_sched_setparam(l->l_proc->p_pid, 0, 2095 spawn_data->sed_attrs->sa_schedpolicy, 2096 &spawn_data->sed_attrs->sa_schedparam); 2097 else if (spawn_data->sed_attrs->sa_flags 2098 & POSIX_SPAWN_SETSCHEDPARAM) { 2099 error = do_sched_setparam(ppid, 0, 2100 SCHED_NONE, &spawn_data->sed_attrs->sa_schedparam); 2101 } 2102 if (error) 2103 goto report_error; 2104 2105 /* Reset user ID's */ 2106 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_RESETIDS) { 2107 error = do_setresuid(l, -1, 2108 kauth_cred_getgid(l->l_cred), -1, 2109 ID_E_EQ_R | ID_E_EQ_S); 2110 if (error) 2111 goto report_error; 2112 error = do_setresuid(l, -1, 2113 kauth_cred_getuid(l->l_cred), -1, 2114 ID_E_EQ_R | ID_E_EQ_S); 2115 if (error) 2116 goto report_error; 2117 } 2118 2119 /* Set signal masks/defaults */ 2120 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETSIGMASK) { 2121 mutex_enter(l->l_proc->p_lock); 2122 error = sigprocmask1(l, SIG_SETMASK, 2123 &spawn_data->sed_attrs->sa_sigmask, NULL); 2124 mutex_exit(l->l_proc->p_lock); 2125 if (error) 2126 goto report_error; 2127 } 2128 2129 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETSIGDEF) { 2130 /* 2131 * The following sigaction call is using a sigaction 2132 * version 0 trampoline which is in the compatibility 2133 * code only. This is not a problem because for SIG_DFL 2134 * and SIG_IGN, the trampolines are now ignored. If they 2135 * were not, this would be a problem because we are 2136 * holding the exec_lock, and the compat code needs 2137 * to do the same in order to replace the trampoline 2138 * code of the process. 2139 */ 2140 for (i = 1; i <= NSIG; i++) { 2141 if (sigismember( 2142 &spawn_data->sed_attrs->sa_sigdefault, i)) 2143 sigaction1(l, i, &sigact, NULL, NULL, 2144 0); 2145 } 2146 } 2147 l->l_proc->p_stat = ostat; 2148 } 2149 2150 /* now do the real exec */ 2151 error = execve_runproc(l, &spawn_data->sed_exec, parent_is_waiting, 2152 true); 2153 have_reflock = false; 2154 if (error == EJUSTRETURN) 2155 error = 0; 2156 else if (error) 2157 goto report_error; 2158 2159 if (parent_is_waiting) { 2160 mutex_enter(&spawn_data->sed_mtx_child); 2161 cv_signal(&spawn_data->sed_cv_child_ready); 2162 mutex_exit(&spawn_data->sed_mtx_child); 2163 } 2164 2165 /* release our refcount on the data */ 2166 spawn_exec_data_release(spawn_data); 2167 2168 /* and finally: leave to userland for the first time */ 2169 cpu_spawn_return(l); 2170 2171 /* NOTREACHED */ 2172 return; 2173 2174 report_error: 2175 if (have_reflock) { 2176 /* 2177 * We have not passed through execve_runproc(), 2178 * which would have released the p_reflock and also 2179 * taken ownership of the sed_exec part of spawn_data, 2180 * so release/free both here. 2181 */ 2182 rw_exit(&l->l_proc->p_reflock); 2183 execve_free_data(&spawn_data->sed_exec); 2184 } 2185 2186 if (parent_is_waiting) { 2187 /* pass error to parent */ 2188 mutex_enter(&spawn_data->sed_mtx_child); 2189 spawn_data->sed_error = error; 2190 cv_signal(&spawn_data->sed_cv_child_ready); 2191 mutex_exit(&spawn_data->sed_mtx_child); 2192 } else { 2193 rw_exit(&exec_lock); 2194 } 2195 2196 /* release our refcount on the data */ 2197 spawn_exec_data_release(spawn_data); 2198 2199 /* done, exit */ 2200 mutex_enter(l->l_proc->p_lock); 2201 /* 2202 * Posix explicitly asks for an exit code of 127 if we report 2203 * errors from the child process - so, unfortunately, there 2204 * is no way to report a more exact error code. 2205 * A NetBSD specific workaround is POSIX_SPAWN_RETURNERROR as 2206 * flag bit in the attrp argument to posix_spawn(2), see above. 2207 */ 2208 exit1(l, W_EXITCODE(127, 0)); 2209 } 2210 2211 void 2212 posix_spawn_fa_free(struct posix_spawn_file_actions *fa, size_t len) 2213 { 2214 2215 for (size_t i = 0; i < len; i++) { 2216 struct posix_spawn_file_actions_entry *fae = &fa->fae[i]; 2217 if (fae->fae_action != FAE_OPEN) 2218 continue; 2219 kmem_free(fae->fae_path, strlen(fae->fae_path) + 1); 2220 } 2221 if (fa->len > 0) 2222 kmem_free(fa->fae, sizeof(*fa->fae) * fa->len); 2223 kmem_free(fa, sizeof(*fa)); 2224 } 2225 2226 static int 2227 posix_spawn_fa_alloc(struct posix_spawn_file_actions **fap, 2228 const struct posix_spawn_file_actions *ufa, rlim_t lim) 2229 { 2230 struct posix_spawn_file_actions *fa; 2231 struct posix_spawn_file_actions_entry *fae; 2232 char *pbuf = NULL; 2233 int error; 2234 size_t i = 0; 2235 2236 fa = kmem_alloc(sizeof(*fa), KM_SLEEP); 2237 error = copyin(ufa, fa, sizeof(*fa)); 2238 if (error || fa->len == 0) { 2239 kmem_free(fa, sizeof(*fa)); 2240 return error; /* 0 if not an error, and len == 0 */ 2241 } 2242 2243 if (fa->len > lim) { 2244 kmem_free(fa, sizeof(*fa)); 2245 return EINVAL; 2246 } 2247 2248 fa->size = fa->len; 2249 size_t fal = fa->len * sizeof(*fae); 2250 fae = fa->fae; 2251 fa->fae = kmem_alloc(fal, KM_SLEEP); 2252 error = copyin(fae, fa->fae, fal); 2253 if (error) 2254 goto out; 2255 2256 pbuf = PNBUF_GET(); 2257 for (; i < fa->len; i++) { 2258 fae = &fa->fae[i]; 2259 if (fae->fae_action != FAE_OPEN) 2260 continue; 2261 error = copyinstr(fae->fae_path, pbuf, MAXPATHLEN, &fal); 2262 if (error) 2263 goto out; 2264 fae->fae_path = kmem_alloc(fal, KM_SLEEP); 2265 memcpy(fae->fae_path, pbuf, fal); 2266 } 2267 PNBUF_PUT(pbuf); 2268 2269 *fap = fa; 2270 return 0; 2271 out: 2272 if (pbuf) 2273 PNBUF_PUT(pbuf); 2274 posix_spawn_fa_free(fa, i); 2275 return error; 2276 } 2277 2278 int 2279 check_posix_spawn(struct lwp *l1) 2280 { 2281 int error, tnprocs, count; 2282 uid_t uid; 2283 struct proc *p1; 2284 2285 p1 = l1->l_proc; 2286 uid = kauth_cred_getuid(l1->l_cred); 2287 tnprocs = atomic_inc_uint_nv(&nprocs); 2288 2289 /* 2290 * Although process entries are dynamically created, we still keep 2291 * a global limit on the maximum number we will create. 2292 */ 2293 if (__predict_false(tnprocs >= maxproc)) 2294 error = -1; 2295 else 2296 error = kauth_authorize_process(l1->l_cred, 2297 KAUTH_PROCESS_FORK, p1, KAUTH_ARG(tnprocs), NULL, NULL); 2298 2299 if (error) { 2300 atomic_dec_uint(&nprocs); 2301 return EAGAIN; 2302 } 2303 2304 /* 2305 * Enforce limits. 2306 */ 2307 count = chgproccnt(uid, 1); 2308 if (kauth_authorize_process(l1->l_cred, KAUTH_PROCESS_RLIMIT, 2309 p1, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_BYPASS), 2310 &p1->p_rlimit[RLIMIT_NPROC], KAUTH_ARG(RLIMIT_NPROC)) != 0 && 2311 __predict_false(count > p1->p_rlimit[RLIMIT_NPROC].rlim_cur)) { 2312 (void)chgproccnt(uid, -1); 2313 atomic_dec_uint(&nprocs); 2314 return EAGAIN; 2315 } 2316 2317 return 0; 2318 } 2319 2320 int 2321 do_posix_spawn(struct lwp *l1, pid_t *pid_res, bool *child_ok, const char *path, 2322 struct posix_spawn_file_actions *fa, 2323 struct posix_spawnattr *sa, 2324 char *const *argv, char *const *envp, 2325 execve_fetch_element_t fetch) 2326 { 2327 2328 struct proc *p1, *p2; 2329 struct lwp *l2; 2330 int error; 2331 struct spawn_exec_data *spawn_data; 2332 vaddr_t uaddr; 2333 pid_t pid; 2334 bool have_exec_lock = false; 2335 2336 p1 = l1->l_proc; 2337 2338 /* Allocate and init spawn_data */ 2339 spawn_data = kmem_zalloc(sizeof(*spawn_data), KM_SLEEP); 2340 spawn_data->sed_refcnt = 1; /* only parent so far */ 2341 cv_init(&spawn_data->sed_cv_child_ready, "pspawn"); 2342 mutex_init(&spawn_data->sed_mtx_child, MUTEX_DEFAULT, IPL_NONE); 2343 mutex_enter(&spawn_data->sed_mtx_child); 2344 2345 /* 2346 * Do the first part of the exec now, collect state 2347 * in spawn_data. 2348 */ 2349 error = execve_loadvm(l1, path, argv, 2350 envp, fetch, &spawn_data->sed_exec); 2351 if (error == EJUSTRETURN) 2352 error = 0; 2353 else if (error) 2354 goto error_exit; 2355 2356 have_exec_lock = true; 2357 2358 /* 2359 * Allocate virtual address space for the U-area now, while it 2360 * is still easy to abort the fork operation if we're out of 2361 * kernel virtual address space. 2362 */ 2363 uaddr = uvm_uarea_alloc(); 2364 if (__predict_false(uaddr == 0)) { 2365 error = ENOMEM; 2366 goto error_exit; 2367 } 2368 2369 /* 2370 * Allocate new proc. Borrow proc0 vmspace for it, we will 2371 * replace it with its own before returning to userland 2372 * in the child. 2373 * This is a point of no return, we will have to go through 2374 * the child proc to properly clean it up past this point. 2375 */ 2376 p2 = proc_alloc(); 2377 pid = p2->p_pid; 2378 2379 /* 2380 * Make a proc table entry for the new process. 2381 * Start by zeroing the section of proc that is zero-initialized, 2382 * then copy the section that is copied directly from the parent. 2383 */ 2384 memset(&p2->p_startzero, 0, 2385 (unsigned) ((char *)&p2->p_endzero - (char *)&p2->p_startzero)); 2386 memcpy(&p2->p_startcopy, &p1->p_startcopy, 2387 (unsigned) ((char *)&p2->p_endcopy - (char *)&p2->p_startcopy)); 2388 p2->p_vmspace = proc0.p_vmspace; 2389 2390 TAILQ_INIT(&p2->p_sigpend.sp_info); 2391 2392 LIST_INIT(&p2->p_lwps); 2393 LIST_INIT(&p2->p_sigwaiters); 2394 2395 /* 2396 * Duplicate sub-structures as needed. 2397 * Increase reference counts on shared objects. 2398 * Inherit flags we want to keep. The flags related to SIGCHLD 2399 * handling are important in order to keep a consistent behaviour 2400 * for the child after the fork. If we are a 32-bit process, the 2401 * child will be too. 2402 */ 2403 p2->p_flag = 2404 p1->p_flag & (PK_SUGID | PK_NOCLDWAIT | PK_CLDSIGIGN | PK_32); 2405 p2->p_emul = p1->p_emul; 2406 p2->p_execsw = p1->p_execsw; 2407 2408 mutex_init(&p2->p_stmutex, MUTEX_DEFAULT, IPL_HIGH); 2409 mutex_init(&p2->p_auxlock, MUTEX_DEFAULT, IPL_NONE); 2410 rw_init(&p2->p_reflock); 2411 cv_init(&p2->p_waitcv, "wait"); 2412 cv_init(&p2->p_lwpcv, "lwpwait"); 2413 2414 p2->p_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE); 2415 2416 kauth_proc_fork(p1, p2); 2417 2418 p2->p_raslist = NULL; 2419 p2->p_fd = fd_copy(); 2420 2421 /* XXX racy */ 2422 p2->p_mqueue_cnt = p1->p_mqueue_cnt; 2423 2424 p2->p_cwdi = cwdinit(); 2425 2426 /* 2427 * Note: p_limit (rlimit stuff) is copy-on-write, so normally 2428 * we just need increase pl_refcnt. 2429 */ 2430 if (!p1->p_limit->pl_writeable) { 2431 lim_addref(p1->p_limit); 2432 p2->p_limit = p1->p_limit; 2433 } else { 2434 p2->p_limit = lim_copy(p1->p_limit); 2435 } 2436 2437 p2->p_lflag = 0; 2438 p2->p_sflag = 0; 2439 p2->p_slflag = 0; 2440 p2->p_pptr = p1; 2441 p2->p_ppid = p1->p_pid; 2442 LIST_INIT(&p2->p_children); 2443 2444 p2->p_aio = NULL; 2445 2446 #ifdef KTRACE 2447 /* 2448 * Copy traceflag and tracefile if enabled. 2449 * If not inherited, these were zeroed above. 2450 */ 2451 if (p1->p_traceflag & KTRFAC_INHERIT) { 2452 mutex_enter(&ktrace_lock); 2453 p2->p_traceflag = p1->p_traceflag; 2454 if ((p2->p_tracep = p1->p_tracep) != NULL) 2455 ktradref(p2); 2456 mutex_exit(&ktrace_lock); 2457 } 2458 #endif 2459 2460 /* 2461 * Create signal actions for the child process. 2462 */ 2463 p2->p_sigacts = sigactsinit(p1, 0); 2464 mutex_enter(p1->p_lock); 2465 p2->p_sflag |= 2466 (p1->p_sflag & (PS_STOPFORK | PS_STOPEXEC | PS_NOCLDSTOP)); 2467 sched_proc_fork(p1, p2); 2468 mutex_exit(p1->p_lock); 2469 2470 p2->p_stflag = p1->p_stflag; 2471 2472 /* 2473 * p_stats. 2474 * Copy parts of p_stats, and zero out the rest. 2475 */ 2476 p2->p_stats = pstatscopy(p1->p_stats); 2477 2478 /* copy over machdep flags to the new proc */ 2479 cpu_proc_fork(p1, p2); 2480 2481 /* 2482 * Prepare remaining parts of spawn data 2483 */ 2484 spawn_data->sed_actions = fa; 2485 spawn_data->sed_attrs = sa; 2486 2487 spawn_data->sed_parent = p1; 2488 2489 /* create LWP */ 2490 lwp_create(l1, p2, uaddr, 0, NULL, 0, spawn_return, spawn_data, 2491 &l2, l1->l_class); 2492 l2->l_ctxlink = NULL; /* reset ucontext link */ 2493 2494 /* 2495 * Copy the credential so other references don't see our changes. 2496 * Test to see if this is necessary first, since in the common case 2497 * we won't need a private reference. 2498 */ 2499 if (kauth_cred_geteuid(l2->l_cred) != kauth_cred_getsvuid(l2->l_cred) || 2500 kauth_cred_getegid(l2->l_cred) != kauth_cred_getsvgid(l2->l_cred)) { 2501 l2->l_cred = kauth_cred_copy(l2->l_cred); 2502 kauth_cred_setsvuid(l2->l_cred, kauth_cred_geteuid(l2->l_cred)); 2503 kauth_cred_setsvgid(l2->l_cred, kauth_cred_getegid(l2->l_cred)); 2504 } 2505 2506 /* Update the master credentials. */ 2507 if (l2->l_cred != p2->p_cred) { 2508 kauth_cred_t ocred; 2509 2510 kauth_cred_hold(l2->l_cred); 2511 mutex_enter(p2->p_lock); 2512 ocred = p2->p_cred; 2513 p2->p_cred = l2->l_cred; 2514 mutex_exit(p2->p_lock); 2515 kauth_cred_free(ocred); 2516 } 2517 2518 *child_ok = true; 2519 spawn_data->sed_refcnt = 2; /* child gets it as well */ 2520 #if 0 2521 l2->l_nopreempt = 1; /* start it non-preemptable */ 2522 #endif 2523 2524 /* 2525 * It's now safe for the scheduler and other processes to see the 2526 * child process. 2527 */ 2528 mutex_enter(proc_lock); 2529 2530 if (p1->p_session->s_ttyvp != NULL && p1->p_lflag & PL_CONTROLT) 2531 p2->p_lflag |= PL_CONTROLT; 2532 2533 LIST_INSERT_HEAD(&p1->p_children, p2, p_sibling); 2534 p2->p_exitsig = SIGCHLD; /* signal for parent on exit */ 2535 2536 LIST_INSERT_AFTER(p1, p2, p_pglist); 2537 LIST_INSERT_HEAD(&allproc, p2, p_list); 2538 2539 p2->p_trace_enabled = trace_is_enabled(p2); 2540 #ifdef __HAVE_SYSCALL_INTERN 2541 (*p2->p_emul->e_syscall_intern)(p2); 2542 #endif 2543 2544 /* 2545 * Make child runnable, set start time, and add to run queue except 2546 * if the parent requested the child to start in SSTOP state. 2547 */ 2548 mutex_enter(p2->p_lock); 2549 2550 getmicrotime(&p2->p_stats->p_start); 2551 2552 lwp_lock(l2); 2553 KASSERT(p2->p_nrlwps == 1); 2554 p2->p_nrlwps = 1; 2555 p2->p_stat = SACTIVE; 2556 l2->l_stat = LSRUN; 2557 sched_enqueue(l2, false); 2558 lwp_unlock(l2); 2559 2560 mutex_exit(p2->p_lock); 2561 mutex_exit(proc_lock); 2562 2563 cv_wait(&spawn_data->sed_cv_child_ready, &spawn_data->sed_mtx_child); 2564 error = spawn_data->sed_error; 2565 mutex_exit(&spawn_data->sed_mtx_child); 2566 spawn_exec_data_release(spawn_data); 2567 2568 rw_exit(&p1->p_reflock); 2569 rw_exit(&exec_lock); 2570 have_exec_lock = false; 2571 2572 *pid_res = pid; 2573 return error; 2574 2575 error_exit: 2576 if (have_exec_lock) { 2577 execve_free_data(&spawn_data->sed_exec); 2578 rw_exit(&p1->p_reflock); 2579 rw_exit(&exec_lock); 2580 } 2581 mutex_exit(&spawn_data->sed_mtx_child); 2582 spawn_exec_data_release(spawn_data); 2583 2584 return error; 2585 } 2586 2587 int 2588 sys_posix_spawn(struct lwp *l1, const struct sys_posix_spawn_args *uap, 2589 register_t *retval) 2590 { 2591 /* { 2592 syscallarg(pid_t *) pid; 2593 syscallarg(const char *) path; 2594 syscallarg(const struct posix_spawn_file_actions *) file_actions; 2595 syscallarg(const struct posix_spawnattr *) attrp; 2596 syscallarg(char *const *) argv; 2597 syscallarg(char *const *) envp; 2598 } */ 2599 2600 int error; 2601 struct posix_spawn_file_actions *fa = NULL; 2602 struct posix_spawnattr *sa = NULL; 2603 pid_t pid; 2604 bool child_ok = false; 2605 rlim_t max_fileactions; 2606 proc_t *p = l1->l_proc; 2607 2608 error = check_posix_spawn(l1); 2609 if (error) { 2610 *retval = error; 2611 return 0; 2612 } 2613 2614 /* copy in file_actions struct */ 2615 if (SCARG(uap, file_actions) != NULL) { 2616 max_fileactions = 2 * min(p->p_rlimit[RLIMIT_NOFILE].rlim_cur, 2617 maxfiles); 2618 error = posix_spawn_fa_alloc(&fa, SCARG(uap, file_actions), 2619 max_fileactions); 2620 if (error) 2621 goto error_exit; 2622 } 2623 2624 /* copyin posix_spawnattr struct */ 2625 if (SCARG(uap, attrp) != NULL) { 2626 sa = kmem_alloc(sizeof(*sa), KM_SLEEP); 2627 error = copyin(SCARG(uap, attrp), sa, sizeof(*sa)); 2628 if (error) 2629 goto error_exit; 2630 } 2631 2632 /* 2633 * Do the spawn 2634 */ 2635 error = do_posix_spawn(l1, &pid, &child_ok, SCARG(uap, path), fa, sa, 2636 SCARG(uap, argv), SCARG(uap, envp), execve_fetch_element); 2637 if (error) 2638 goto error_exit; 2639 2640 if (error == 0 && SCARG(uap, pid) != NULL) 2641 error = copyout(&pid, SCARG(uap, pid), sizeof(pid)); 2642 2643 *retval = error; 2644 return 0; 2645 2646 error_exit: 2647 if (!child_ok) { 2648 (void)chgproccnt(kauth_cred_getuid(l1->l_cred), -1); 2649 atomic_dec_uint(&nprocs); 2650 2651 if (sa) 2652 kmem_free(sa, sizeof(*sa)); 2653 if (fa) 2654 posix_spawn_fa_free(fa, fa->len); 2655 } 2656 2657 *retval = error; 2658 return 0; 2659 } 2660 2661 void 2662 exec_free_emul_arg(struct exec_package *epp) 2663 { 2664 if (epp->ep_emul_arg_free != NULL) { 2665 KASSERT(epp->ep_emul_arg != NULL); 2666 (*epp->ep_emul_arg_free)(epp->ep_emul_arg); 2667 epp->ep_emul_arg_free = NULL; 2668 epp->ep_emul_arg = NULL; 2669 } else { 2670 KASSERT(epp->ep_emul_arg == NULL); 2671 } 2672 } 2673 2674 #ifdef DEBUG_EXEC 2675 static void 2676 dump_vmcmds(const struct exec_package * const epp, size_t x, int error) 2677 { 2678 struct exec_vmcmd *vp = &epp->ep_vmcmds.evs_cmds[0]; 2679 size_t j; 2680 2681 if (error == 0) 2682 DPRINTF(("vmcmds %u\n", epp->ep_vmcmds.evs_used)); 2683 else 2684 DPRINTF(("vmcmds %zu/%u, error %d\n", x, 2685 epp->ep_vmcmds.evs_used, error)); 2686 2687 for (j = 0; j < epp->ep_vmcmds.evs_used; j++) { 2688 DPRINTF(("vmcmd[%zu] = vmcmd_map_%s %#" 2689 PRIxVADDR"/%#"PRIxVSIZE" fd@%#" 2690 PRIxVSIZE" prot=0%o flags=%d\n", j, 2691 vp[j].ev_proc == vmcmd_map_pagedvn ? 2692 "pagedvn" : 2693 vp[j].ev_proc == vmcmd_map_readvn ? 2694 "readvn" : 2695 vp[j].ev_proc == vmcmd_map_zero ? 2696 "zero" : "*unknown*", 2697 vp[j].ev_addr, vp[j].ev_len, 2698 vp[j].ev_offset, vp[j].ev_prot, 2699 vp[j].ev_flags)); 2700 if (error != 0 && j == x) 2701 DPRINTF((" ^--- failed\n")); 2702 } 2703 } 2704 #endif 2705