1 /* $NetBSD: kern_exec.c,v 1.423 2015/11/30 22:47:19 pgoyette 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 1.423 2015/11/30 22:47:19 pgoyette 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_PROVIDER_DECLARE(proc); 152 SDT_PROBE_DEFINE1(proc, kernel, , exec, "char *"); 153 SDT_PROBE_DEFINE1(proc, kernel, , exec__success, "char *"); 154 SDT_PROBE_DEFINE1(proc, kernel, , exec__failure, "int"); 155 156 /* 157 * Exec function switch: 158 * 159 * Note that each makecmds function is responsible for loading the 160 * exec package with the necessary functions for any exec-type-specific 161 * handling. 162 * 163 * Functions for specific exec types should be defined in their own 164 * header file. 165 */ 166 static const struct execsw **execsw = NULL; 167 static int nexecs; 168 169 u_int exec_maxhdrsz; /* must not be static - used by netbsd32 */ 170 171 /* list of dynamically loaded execsw entries */ 172 static LIST_HEAD(execlist_head, exec_entry) ex_head = 173 LIST_HEAD_INITIALIZER(ex_head); 174 struct exec_entry { 175 LIST_ENTRY(exec_entry) ex_list; 176 SLIST_ENTRY(exec_entry) ex_slist; 177 const struct execsw *ex_sw; 178 }; 179 180 #ifndef __HAVE_SYSCALL_INTERN 181 void syscall(void); 182 #endif 183 184 /* NetBSD autoloadable syscalls */ 185 #ifdef MODULAR 186 #include <kern/syscalls_autoload.c> 187 #endif 188 189 /* NetBSD emul struct */ 190 struct emul emul_netbsd = { 191 .e_name = "netbsd", 192 #ifdef EMUL_NATIVEROOT 193 .e_path = EMUL_NATIVEROOT, 194 #else 195 .e_path = NULL, 196 #endif 197 #ifndef __HAVE_MINIMAL_EMUL 198 .e_flags = EMUL_HAS_SYS___syscall, 199 .e_errno = NULL, 200 .e_nosys = SYS_syscall, 201 .e_nsysent = SYS_NSYSENT, 202 #endif 203 #ifdef MODULAR 204 .e_sc_autoload = netbsd_syscalls_autoload, 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 /* 462 * Reset all the fields that may have been modified by the 463 * loader. 464 */ 465 KASSERT(epp->ep_emul_arg == NULL); 466 if (epp->ep_emul_root != NULL) { 467 vrele(epp->ep_emul_root); 468 epp->ep_emul_root = NULL; 469 } 470 if (epp->ep_interp != NULL) { 471 vrele(epp->ep_interp); 472 epp->ep_interp = NULL; 473 } 474 epp->ep_pax_flags = 0; 475 476 /* make sure the first "interesting" error code is saved. */ 477 if (error == ENOEXEC) 478 error = newerror; 479 480 if (epp->ep_flags & EXEC_DESTR) 481 /* Error from "#!" code, tidied up by recursive call */ 482 return error; 483 } 484 485 /* not found, error */ 486 487 /* 488 * free any vmspace-creation commands, 489 * and release their references 490 */ 491 kill_vmcmds(&epp->ep_vmcmds); 492 493 bad2: 494 /* 495 * close and release the vnode, restore the old one, free the 496 * pathname buf, and punt. 497 */ 498 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 499 VOP_CLOSE(vp, FREAD, l->l_cred); 500 vput(vp); 501 return error; 502 503 bad1: 504 /* 505 * free the namei pathname buffer, and put the vnode 506 * (which we don't yet have open). 507 */ 508 vput(vp); /* was still locked */ 509 return error; 510 } 511 512 #ifdef __MACHINE_STACK_GROWS_UP 513 #define STACK_PTHREADSPACE NBPG 514 #else 515 #define STACK_PTHREADSPACE 0 516 #endif 517 518 static int 519 execve_fetch_element(char * const *array, size_t index, char **value) 520 { 521 return copyin(array + index, value, sizeof(*value)); 522 } 523 524 /* 525 * exec system call 526 */ 527 int 528 sys_execve(struct lwp *l, const struct sys_execve_args *uap, register_t *retval) 529 { 530 /* { 531 syscallarg(const char *) path; 532 syscallarg(char * const *) argp; 533 syscallarg(char * const *) envp; 534 } */ 535 536 return execve1(l, SCARG(uap, path), SCARG(uap, argp), 537 SCARG(uap, envp), execve_fetch_element); 538 } 539 540 int 541 sys_fexecve(struct lwp *l, const struct sys_fexecve_args *uap, 542 register_t *retval) 543 { 544 /* { 545 syscallarg(int) fd; 546 syscallarg(char * const *) argp; 547 syscallarg(char * const *) envp; 548 } */ 549 550 return ENOSYS; 551 } 552 553 /* 554 * Load modules to try and execute an image that we do not understand. 555 * If no execsw entries are present, we load those likely to be needed 556 * in order to run native images only. Otherwise, we autoload all 557 * possible modules that could let us run the binary. XXX lame 558 */ 559 static void 560 exec_autoload(void) 561 { 562 #ifdef MODULAR 563 static const char * const native[] = { 564 "exec_elf32", 565 "exec_elf64", 566 "exec_script", 567 NULL 568 }; 569 static const char * const compat[] = { 570 "exec_elf32", 571 "exec_elf64", 572 "exec_script", 573 "exec_aout", 574 "exec_coff", 575 "exec_ecoff", 576 "compat_aoutm68k", 577 "compat_freebsd", 578 "compat_ibcs2", 579 "compat_linux", 580 "compat_linux32", 581 "compat_netbsd32", 582 "compat_sunos", 583 "compat_sunos32", 584 "compat_svr4", 585 "compat_svr4_32", 586 "compat_ultrix", 587 NULL 588 }; 589 char const * const *list; 590 int i; 591 592 list = (nexecs == 0 ? native : compat); 593 for (i = 0; list[i] != NULL; i++) { 594 if (module_autoload(list[i], MODULE_CLASS_EXEC) != 0) { 595 continue; 596 } 597 yield(); 598 } 599 #endif 600 } 601 602 static int 603 makepathbuf(struct lwp *l, const char *upath, struct pathbuf **pbp, 604 size_t *offs) 605 { 606 char *path, *bp; 607 size_t len, tlen; 608 int error; 609 struct cwdinfo *cwdi; 610 611 path = PNBUF_GET(); 612 error = copyinstr(upath, path, MAXPATHLEN, &len); 613 if (error) { 614 PNBUF_PUT(path); 615 DPRINTF(("%s: copyin path @%p %d\n", __func__, upath, error)); 616 return error; 617 } 618 619 if (path[0] == '/') { 620 *offs = 0; 621 goto out; 622 } 623 624 len++; 625 if (len + 1 >= MAXPATHLEN) 626 goto out; 627 bp = path + MAXPATHLEN - len; 628 memmove(bp, path, len); 629 *(--bp) = '/'; 630 631 cwdi = l->l_proc->p_cwdi; 632 rw_enter(&cwdi->cwdi_lock, RW_READER); 633 error = getcwd_common(cwdi->cwdi_cdir, NULL, &bp, path, MAXPATHLEN / 2, 634 GETCWD_CHECK_ACCESS, l); 635 rw_exit(&cwdi->cwdi_lock); 636 637 if (error) { 638 DPRINTF(("%s: getcwd_common path %s %d\n", __func__, path, 639 error)); 640 goto out; 641 } 642 tlen = path + MAXPATHLEN - bp; 643 644 memmove(path, bp, tlen); 645 path[tlen] = '\0'; 646 *offs = tlen - len; 647 out: 648 *pbp = pathbuf_assimilate(path); 649 return 0; 650 } 651 652 static int 653 execve_loadvm(struct lwp *l, const char *path, char * const *args, 654 char * const *envs, execve_fetch_element_t fetch_element, 655 struct execve_data * restrict data) 656 { 657 struct exec_package * const epp = &data->ed_pack; 658 int error; 659 struct proc *p; 660 char *dp; 661 u_int modgen; 662 size_t offs = 0; // XXX: GCC 663 664 KASSERT(data != NULL); 665 666 p = l->l_proc; 667 modgen = 0; 668 669 SDT_PROBE(proc, kernel, , exec, path, 0, 0, 0, 0); 670 671 /* 672 * Check if we have exceeded our number of processes limit. 673 * This is so that we handle the case where a root daemon 674 * forked, ran setuid to become the desired user and is trying 675 * to exec. The obvious place to do the reference counting check 676 * is setuid(), but we don't do the reference counting check there 677 * like other OS's do because then all the programs that use setuid() 678 * must be modified to check the return code of setuid() and exit(). 679 * It is dangerous to make setuid() fail, because it fails open and 680 * the program will continue to run as root. If we make it succeed 681 * and return an error code, again we are not enforcing the limit. 682 * The best place to enforce the limit is here, when the process tries 683 * to execute a new image, because eventually the process will need 684 * to call exec in order to do something useful. 685 */ 686 retry: 687 if (p->p_flag & PK_SUGID) { 688 if (kauth_authorize_process(l->l_cred, KAUTH_PROCESS_RLIMIT, 689 p, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_BYPASS), 690 &p->p_rlimit[RLIMIT_NPROC], 691 KAUTH_ARG(RLIMIT_NPROC)) != 0 && 692 chgproccnt(kauth_cred_getuid(l->l_cred), 0) > 693 p->p_rlimit[RLIMIT_NPROC].rlim_cur) 694 return EAGAIN; 695 } 696 697 /* 698 * Drain existing references and forbid new ones. The process 699 * should be left alone until we're done here. This is necessary 700 * to avoid race conditions - e.g. in ptrace() - that might allow 701 * a local user to illicitly obtain elevated privileges. 702 */ 703 rw_enter(&p->p_reflock, RW_WRITER); 704 705 /* 706 * Init the namei data to point the file user's program name. 707 * This is done here rather than in check_exec(), so that it's 708 * possible to override this settings if any of makecmd/probe 709 * functions call check_exec() recursively - for example, 710 * see exec_script_makecmds(). 711 */ 712 if ((error = makepathbuf(l, path, &data->ed_pathbuf, &offs)) != 0) 713 goto clrflg; 714 data->ed_pathstring = pathbuf_stringcopy_get(data->ed_pathbuf); 715 data->ed_resolvedpathbuf = PNBUF_GET(); 716 717 /* 718 * initialize the fields of the exec package. 719 */ 720 epp->ep_kname = data->ed_pathstring + offs; 721 epp->ep_resolvedname = data->ed_resolvedpathbuf; 722 epp->ep_hdr = kmem_alloc(exec_maxhdrsz, KM_SLEEP); 723 epp->ep_hdrlen = exec_maxhdrsz; 724 epp->ep_hdrvalid = 0; 725 epp->ep_emul_arg = NULL; 726 epp->ep_emul_arg_free = NULL; 727 memset(&epp->ep_vmcmds, 0, sizeof(epp->ep_vmcmds)); 728 epp->ep_vap = &data->ed_attr; 729 epp->ep_flags = (p->p_flag & PK_32) ? EXEC_FROM32 : 0; 730 MD_TOPDOWN_INIT(epp); 731 epp->ep_emul_root = NULL; 732 epp->ep_interp = NULL; 733 epp->ep_esch = NULL; 734 epp->ep_pax_flags = 0; 735 memset(epp->ep_machine_arch, 0, sizeof(epp->ep_machine_arch)); 736 737 rw_enter(&exec_lock, RW_READER); 738 739 /* see if we can run it. */ 740 if ((error = check_exec(l, epp, data->ed_pathbuf)) != 0) { 741 if (error != ENOENT) { 742 DPRINTF(("%s: check exec failed %d\n", 743 __func__, error)); 744 } 745 goto freehdr; 746 } 747 748 /* allocate an argument buffer */ 749 data->ed_argp = pool_get(&exec_pool, PR_WAITOK); 750 KASSERT(data->ed_argp != NULL); 751 dp = data->ed_argp; 752 753 if ((error = copyinargs(data, args, envs, fetch_element, &dp)) != 0) { 754 goto bad; 755 } 756 757 /* 758 * Calculate the new stack size. 759 */ 760 761 #ifdef PAX_ASLR 762 #define ASLR_GAP(epp) (pax_aslr_epp_active(epp) ? (cprng_fast32() % PAGE_SIZE) : 0) 763 #else 764 #define ASLR_GAP(epp) 0 765 #endif 766 767 #ifdef __MACHINE_STACK_GROWS_UP 768 /* 769 * copyargs() fills argc/argv/envp from the lower address even on 770 * __MACHINE_STACK_GROWS_UP machines. Reserve a few words just below the SP 771 * so that _rtld() use it. 772 */ 773 #define RTLD_GAP 32 774 #else 775 #define RTLD_GAP 0 776 #endif 777 778 const size_t argenvstrlen = (char *)ALIGN(dp) - data->ed_argp; 779 780 data->ed_argslen = calcargs(data, argenvstrlen); 781 782 const size_t len = calcstack(data, ASLR_GAP(epp) + RTLD_GAP); 783 784 if (len > epp->ep_ssize) { 785 /* in effect, compare to initial limit */ 786 DPRINTF(("%s: stack limit exceeded %zu\n", __func__, len)); 787 error = ENOMEM; 788 goto bad; 789 } 790 /* adjust "active stack depth" for process VSZ */ 791 epp->ep_ssize = len; 792 793 return 0; 794 795 bad: 796 /* free the vmspace-creation commands, and release their references */ 797 kill_vmcmds(&epp->ep_vmcmds); 798 /* kill any opened file descriptor, if necessary */ 799 if (epp->ep_flags & EXEC_HASFD) { 800 epp->ep_flags &= ~EXEC_HASFD; 801 fd_close(epp->ep_fd); 802 } 803 /* close and put the exec'd file */ 804 vn_lock(epp->ep_vp, LK_EXCLUSIVE | LK_RETRY); 805 VOP_CLOSE(epp->ep_vp, FREAD, l->l_cred); 806 vput(epp->ep_vp); 807 pool_put(&exec_pool, data->ed_argp); 808 809 freehdr: 810 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 811 if (epp->ep_emul_root != NULL) 812 vrele(epp->ep_emul_root); 813 if (epp->ep_interp != NULL) 814 vrele(epp->ep_interp); 815 816 rw_exit(&exec_lock); 817 818 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 819 pathbuf_destroy(data->ed_pathbuf); 820 PNBUF_PUT(data->ed_resolvedpathbuf); 821 822 clrflg: 823 rw_exit(&p->p_reflock); 824 825 if (modgen != module_gen && error == ENOEXEC) { 826 modgen = module_gen; 827 exec_autoload(); 828 goto retry; 829 } 830 831 SDT_PROBE(proc, kernel, , exec__failure, error, 0, 0, 0, 0); 832 return error; 833 } 834 835 static int 836 execve_dovmcmds(struct lwp *l, struct execve_data * restrict data) 837 { 838 struct exec_package * const epp = &data->ed_pack; 839 struct proc *p = l->l_proc; 840 struct exec_vmcmd *base_vcp; 841 int error = 0; 842 size_t i; 843 844 /* record proc's vnode, for use by procfs and others */ 845 if (p->p_textvp) 846 vrele(p->p_textvp); 847 vref(epp->ep_vp); 848 p->p_textvp = epp->ep_vp; 849 850 /* create the new process's VM space by running the vmcmds */ 851 KASSERTMSG(epp->ep_vmcmds.evs_used != 0, "%s: no vmcmds", __func__); 852 853 DUMPVMCMDS(epp, 0, 0); 854 855 base_vcp = NULL; 856 857 for (i = 0; i < epp->ep_vmcmds.evs_used && !error; i++) { 858 struct exec_vmcmd *vcp; 859 860 vcp = &epp->ep_vmcmds.evs_cmds[i]; 861 if (vcp->ev_flags & VMCMD_RELATIVE) { 862 KASSERTMSG(base_vcp != NULL, 863 "%s: relative vmcmd with no base", __func__); 864 KASSERTMSG((vcp->ev_flags & VMCMD_BASE) == 0, 865 "%s: illegal base & relative vmcmd", __func__); 866 vcp->ev_addr += base_vcp->ev_addr; 867 } 868 error = (*vcp->ev_proc)(l, vcp); 869 if (error) 870 DUMPVMCMDS(epp, i, error); 871 if (vcp->ev_flags & VMCMD_BASE) 872 base_vcp = vcp; 873 } 874 875 /* free the vmspace-creation commands, and release their references */ 876 kill_vmcmds(&epp->ep_vmcmds); 877 878 vn_lock(epp->ep_vp, LK_EXCLUSIVE | LK_RETRY); 879 VOP_CLOSE(epp->ep_vp, FREAD, l->l_cred); 880 vput(epp->ep_vp); 881 882 /* if an error happened, deallocate and punt */ 883 if (error != 0) { 884 DPRINTF(("%s: vmcmd %zu failed: %d\n", __func__, i - 1, error)); 885 } 886 return error; 887 } 888 889 static void 890 execve_free_data(struct execve_data *data) 891 { 892 struct exec_package * const epp = &data->ed_pack; 893 894 /* free the vmspace-creation commands, and release their references */ 895 kill_vmcmds(&epp->ep_vmcmds); 896 /* kill any opened file descriptor, if necessary */ 897 if (epp->ep_flags & EXEC_HASFD) { 898 epp->ep_flags &= ~EXEC_HASFD; 899 fd_close(epp->ep_fd); 900 } 901 902 /* close and put the exec'd file */ 903 vn_lock(epp->ep_vp, LK_EXCLUSIVE | LK_RETRY); 904 VOP_CLOSE(epp->ep_vp, FREAD, curlwp->l_cred); 905 vput(epp->ep_vp); 906 pool_put(&exec_pool, data->ed_argp); 907 908 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 909 if (epp->ep_emul_root != NULL) 910 vrele(epp->ep_emul_root); 911 if (epp->ep_interp != NULL) 912 vrele(epp->ep_interp); 913 914 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 915 pathbuf_destroy(data->ed_pathbuf); 916 PNBUF_PUT(data->ed_resolvedpathbuf); 917 } 918 919 static void 920 pathexec(struct exec_package *epp, struct proc *p, const char *pathstring) 921 { 922 const char *commandname; 923 size_t commandlen; 924 char *path; 925 926 /* set command name & other accounting info */ 927 commandname = strrchr(epp->ep_resolvedname, '/'); 928 if (commandname != NULL) { 929 commandname++; 930 } else { 931 commandname = epp->ep_resolvedname; 932 } 933 commandlen = min(strlen(commandname), MAXCOMLEN); 934 (void)memcpy(p->p_comm, commandname, commandlen); 935 p->p_comm[commandlen] = '\0'; 936 937 938 /* 939 * If the path starts with /, we don't need to do any work. 940 * This handles the majority of the cases. 941 * In the future perhaps we could canonicalize it? 942 */ 943 if (pathstring[0] == '/') { 944 path = PNBUF_GET(); 945 (void)strlcpy(path, pathstring, MAXPATHLEN); 946 epp->ep_path = path; 947 } else 948 epp->ep_path = NULL; 949 } 950 951 /* XXX elsewhere */ 952 static int 953 credexec(struct lwp *l, struct vattr *attr) 954 { 955 struct proc *p = l->l_proc; 956 int error; 957 958 /* 959 * Deal with set[ug]id. MNT_NOSUID has already been used to disable 960 * s[ug]id. It's OK to check for PSL_TRACED here as we have blocked 961 * out additional references on the process for the moment. 962 */ 963 if ((p->p_slflag & PSL_TRACED) == 0 && 964 965 (((attr->va_mode & S_ISUID) != 0 && 966 kauth_cred_geteuid(l->l_cred) != attr->va_uid) || 967 968 ((attr->va_mode & S_ISGID) != 0 && 969 kauth_cred_getegid(l->l_cred) != attr->va_gid))) { 970 /* 971 * Mark the process as SUGID before we do 972 * anything that might block. 973 */ 974 proc_crmod_enter(); 975 proc_crmod_leave(NULL, NULL, true); 976 977 /* Make sure file descriptors 0..2 are in use. */ 978 if ((error = fd_checkstd()) != 0) { 979 DPRINTF(("%s: fdcheckstd failed %d\n", 980 __func__, error)); 981 return error; 982 } 983 984 /* 985 * Copy the credential so other references don't see our 986 * changes. 987 */ 988 l->l_cred = kauth_cred_copy(l->l_cred); 989 #ifdef KTRACE 990 /* 991 * If the persistent trace flag isn't set, turn off. 992 */ 993 if (p->p_tracep) { 994 mutex_enter(&ktrace_lock); 995 if (!(p->p_traceflag & KTRFAC_PERSISTENT)) 996 ktrderef(p); 997 mutex_exit(&ktrace_lock); 998 } 999 #endif 1000 if (attr->va_mode & S_ISUID) 1001 kauth_cred_seteuid(l->l_cred, attr->va_uid); 1002 if (attr->va_mode & S_ISGID) 1003 kauth_cred_setegid(l->l_cred, attr->va_gid); 1004 } else { 1005 if (kauth_cred_geteuid(l->l_cred) == 1006 kauth_cred_getuid(l->l_cred) && 1007 kauth_cred_getegid(l->l_cred) == 1008 kauth_cred_getgid(l->l_cred)) 1009 p->p_flag &= ~PK_SUGID; 1010 } 1011 1012 /* 1013 * Copy the credential so other references don't see our changes. 1014 * Test to see if this is necessary first, since in the common case 1015 * we won't need a private reference. 1016 */ 1017 if (kauth_cred_geteuid(l->l_cred) != kauth_cred_getsvuid(l->l_cred) || 1018 kauth_cred_getegid(l->l_cred) != kauth_cred_getsvgid(l->l_cred)) { 1019 l->l_cred = kauth_cred_copy(l->l_cred); 1020 kauth_cred_setsvuid(l->l_cred, kauth_cred_geteuid(l->l_cred)); 1021 kauth_cred_setsvgid(l->l_cred, kauth_cred_getegid(l->l_cred)); 1022 } 1023 1024 /* Update the master credentials. */ 1025 if (l->l_cred != p->p_cred) { 1026 kauth_cred_t ocred; 1027 1028 kauth_cred_hold(l->l_cred); 1029 mutex_enter(p->p_lock); 1030 ocred = p->p_cred; 1031 p->p_cred = l->l_cred; 1032 mutex_exit(p->p_lock); 1033 kauth_cred_free(ocred); 1034 } 1035 1036 return 0; 1037 } 1038 1039 static void 1040 emulexec(struct lwp *l, struct exec_package *epp) 1041 { 1042 struct proc *p = l->l_proc; 1043 1044 /* The emulation root will usually have been found when we looked 1045 * for the elf interpreter (or similar), if not look now. */ 1046 if (epp->ep_esch->es_emul->e_path != NULL && 1047 epp->ep_emul_root == NULL) 1048 emul_find_root(l, epp); 1049 1050 /* Any old emulation root got removed by fdcloseexec */ 1051 rw_enter(&p->p_cwdi->cwdi_lock, RW_WRITER); 1052 p->p_cwdi->cwdi_edir = epp->ep_emul_root; 1053 rw_exit(&p->p_cwdi->cwdi_lock); 1054 epp->ep_emul_root = NULL; 1055 if (epp->ep_interp != NULL) 1056 vrele(epp->ep_interp); 1057 1058 /* 1059 * Call emulation specific exec hook. This can setup per-process 1060 * p->p_emuldata or do any other per-process stuff an emulation needs. 1061 * 1062 * If we are executing process of different emulation than the 1063 * original forked process, call e_proc_exit() of the old emulation 1064 * first, then e_proc_exec() of new emulation. If the emulation is 1065 * same, the exec hook code should deallocate any old emulation 1066 * resources held previously by this process. 1067 */ 1068 if (p->p_emul && p->p_emul->e_proc_exit 1069 && p->p_emul != epp->ep_esch->es_emul) 1070 (*p->p_emul->e_proc_exit)(p); 1071 1072 /* 1073 * This is now LWP 1. 1074 */ 1075 /* XXX elsewhere */ 1076 mutex_enter(p->p_lock); 1077 p->p_nlwpid = 1; 1078 l->l_lid = 1; 1079 mutex_exit(p->p_lock); 1080 1081 /* 1082 * Call exec hook. Emulation code may NOT store reference to anything 1083 * from &pack. 1084 */ 1085 if (epp->ep_esch->es_emul->e_proc_exec) 1086 (*epp->ep_esch->es_emul->e_proc_exec)(p, epp); 1087 1088 /* update p_emul, the old value is no longer needed */ 1089 p->p_emul = epp->ep_esch->es_emul; 1090 1091 /* ...and the same for p_execsw */ 1092 p->p_execsw = epp->ep_esch; 1093 1094 #ifdef __HAVE_SYSCALL_INTERN 1095 (*p->p_emul->e_syscall_intern)(p); 1096 #endif 1097 ktremul(); 1098 } 1099 1100 static int 1101 execve_runproc(struct lwp *l, struct execve_data * restrict data, 1102 bool no_local_exec_lock, bool is_spawn) 1103 { 1104 struct exec_package * const epp = &data->ed_pack; 1105 int error = 0; 1106 struct proc *p; 1107 1108 /* 1109 * In case of a posix_spawn operation, the child doing the exec 1110 * might not hold the reader lock on exec_lock, but the parent 1111 * will do this instead. 1112 */ 1113 KASSERT(no_local_exec_lock || rw_lock_held(&exec_lock)); 1114 KASSERT(!no_local_exec_lock || is_spawn); 1115 KASSERT(data != NULL); 1116 1117 p = l->l_proc; 1118 1119 /* Get rid of other LWPs. */ 1120 if (p->p_nlwps > 1) { 1121 mutex_enter(p->p_lock); 1122 exit_lwps(l); 1123 mutex_exit(p->p_lock); 1124 } 1125 KDASSERT(p->p_nlwps == 1); 1126 1127 /* Destroy any lwpctl info. */ 1128 if (p->p_lwpctl != NULL) 1129 lwp_ctl_exit(); 1130 1131 /* Remove POSIX timers */ 1132 timers_free(p, TIMERS_POSIX); 1133 1134 /* Set the PaX flags. */ 1135 p->p_pax = epp->ep_pax_flags; 1136 1137 /* 1138 * Do whatever is necessary to prepare the address space 1139 * for remapping. Note that this might replace the current 1140 * vmspace with another! 1141 */ 1142 if (is_spawn) 1143 uvmspace_spawn(l, epp->ep_vm_minaddr, 1144 epp->ep_vm_maxaddr, 1145 epp->ep_flags & EXEC_TOPDOWN_VM); 1146 else 1147 uvmspace_exec(l, epp->ep_vm_minaddr, 1148 epp->ep_vm_maxaddr, 1149 epp->ep_flags & EXEC_TOPDOWN_VM); 1150 1151 struct vmspace *vm; 1152 vm = p->p_vmspace; 1153 vm->vm_taddr = (void *)epp->ep_taddr; 1154 vm->vm_tsize = btoc(epp->ep_tsize); 1155 vm->vm_daddr = (void*)epp->ep_daddr; 1156 vm->vm_dsize = btoc(epp->ep_dsize); 1157 vm->vm_ssize = btoc(epp->ep_ssize); 1158 vm->vm_issize = 0; 1159 vm->vm_maxsaddr = (void *)epp->ep_maxsaddr; 1160 vm->vm_minsaddr = (void *)epp->ep_minsaddr; 1161 1162 #ifdef PAX_ASLR 1163 pax_aslr_init_vm(l, vm); 1164 #endif /* PAX_ASLR */ 1165 1166 /* Now map address space. */ 1167 error = execve_dovmcmds(l, data); 1168 if (error != 0) 1169 goto exec_abort; 1170 1171 pathexec(epp, p, data->ed_pathstring); 1172 1173 char * const newstack = STACK_GROW(vm->vm_minsaddr, epp->ep_ssize); 1174 1175 error = copyoutargs(data, l, newstack); 1176 if (error != 0) 1177 goto exec_abort; 1178 1179 cwdexec(p); 1180 fd_closeexec(); /* handle close on exec */ 1181 1182 if (__predict_false(ktrace_on)) 1183 fd_ktrexecfd(); 1184 1185 execsigs(p); /* reset catched signals */ 1186 1187 mutex_enter(p->p_lock); 1188 l->l_ctxlink = NULL; /* reset ucontext link */ 1189 p->p_acflag &= ~AFORK; 1190 p->p_flag |= PK_EXEC; 1191 mutex_exit(p->p_lock); 1192 1193 /* 1194 * Stop profiling. 1195 */ 1196 if ((p->p_stflag & PST_PROFIL) != 0) { 1197 mutex_spin_enter(&p->p_stmutex); 1198 stopprofclock(p); 1199 mutex_spin_exit(&p->p_stmutex); 1200 } 1201 1202 /* 1203 * It's OK to test PL_PPWAIT unlocked here, as other LWPs have 1204 * exited and exec()/exit() are the only places it will be cleared. 1205 */ 1206 if ((p->p_lflag & PL_PPWAIT) != 0) { 1207 #if 0 1208 lwp_t *lp; 1209 1210 mutex_enter(proc_lock); 1211 lp = p->p_vforklwp; 1212 p->p_vforklwp = NULL; 1213 1214 l->l_lwpctl = NULL; /* was on loan from blocked parent */ 1215 p->p_lflag &= ~PL_PPWAIT; 1216 1217 lp->l_pflag &= ~LP_VFORKWAIT; /* XXX */ 1218 cv_broadcast(&lp->l_waitcv); 1219 mutex_exit(proc_lock); 1220 #else 1221 mutex_enter(proc_lock); 1222 l->l_lwpctl = NULL; /* was on loan from blocked parent */ 1223 p->p_lflag &= ~PL_PPWAIT; 1224 cv_broadcast(&p->p_pptr->p_waitcv); 1225 mutex_exit(proc_lock); 1226 #endif 1227 } 1228 1229 error = credexec(l, &data->ed_attr); 1230 if (error) 1231 goto exec_abort; 1232 1233 #if defined(__HAVE_RAS) 1234 /* 1235 * Remove all RASs from the address space. 1236 */ 1237 ras_purgeall(); 1238 #endif 1239 1240 doexechooks(p); 1241 1242 /* 1243 * Set initial SP at the top of the stack. 1244 * 1245 * Note that on machines where stack grows up (e.g. hppa), SP points to 1246 * the end of arg/env strings. Userland guesses the address of argc 1247 * via ps_strings::ps_argvstr. 1248 */ 1249 1250 /* Setup new registers and do misc. setup. */ 1251 (*epp->ep_esch->es_emul->e_setregs)(l, epp, (vaddr_t)newstack); 1252 if (epp->ep_esch->es_setregs) 1253 (*epp->ep_esch->es_setregs)(l, epp, (vaddr_t)newstack); 1254 1255 /* Provide a consistent LWP private setting */ 1256 (void)lwp_setprivate(l, NULL); 1257 1258 /* Discard all PCU state; need to start fresh */ 1259 pcu_discard_all(l); 1260 1261 /* map the process's signal trampoline code */ 1262 if ((error = exec_sigcode_map(p, epp->ep_esch->es_emul)) != 0) { 1263 DPRINTF(("%s: map sigcode failed %d\n", __func__, error)); 1264 goto exec_abort; 1265 } 1266 1267 pool_put(&exec_pool, data->ed_argp); 1268 1269 /* notify others that we exec'd */ 1270 KNOTE(&p->p_klist, NOTE_EXEC); 1271 1272 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 1273 1274 SDT_PROBE(proc, kernel, , exec__success, epp->ep_kname, 0, 0, 0, 0); 1275 1276 emulexec(l, epp); 1277 1278 /* Allow new references from the debugger/procfs. */ 1279 rw_exit(&p->p_reflock); 1280 if (!no_local_exec_lock) 1281 rw_exit(&exec_lock); 1282 1283 mutex_enter(proc_lock); 1284 1285 if ((p->p_slflag & (PSL_TRACED|PSL_SYSCALL)) == PSL_TRACED) { 1286 ksiginfo_t ksi; 1287 1288 KSI_INIT_EMPTY(&ksi); 1289 ksi.ksi_signo = SIGTRAP; 1290 ksi.ksi_lid = l->l_lid; 1291 kpsignal(p, &ksi, NULL); 1292 } 1293 1294 if (p->p_sflag & PS_STOPEXEC) { 1295 ksiginfoq_t kq; 1296 1297 KERNEL_UNLOCK_ALL(l, &l->l_biglocks); 1298 p->p_pptr->p_nstopchild++; 1299 p->p_waited = 0; 1300 mutex_enter(p->p_lock); 1301 ksiginfo_queue_init(&kq); 1302 sigclearall(p, &contsigmask, &kq); 1303 lwp_lock(l); 1304 l->l_stat = LSSTOP; 1305 p->p_stat = SSTOP; 1306 p->p_nrlwps--; 1307 lwp_unlock(l); 1308 mutex_exit(p->p_lock); 1309 mutex_exit(proc_lock); 1310 lwp_lock(l); 1311 mi_switch(l); 1312 ksiginfo_queue_drain(&kq); 1313 KERNEL_LOCK(l->l_biglocks, l); 1314 } else { 1315 mutex_exit(proc_lock); 1316 } 1317 1318 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 1319 pathbuf_destroy(data->ed_pathbuf); 1320 PNBUF_PUT(data->ed_resolvedpathbuf); 1321 DPRINTF(("%s finished\n", __func__)); 1322 return EJUSTRETURN; 1323 1324 exec_abort: 1325 SDT_PROBE(proc, kernel, , exec__failure, error, 0, 0, 0, 0); 1326 rw_exit(&p->p_reflock); 1327 if (!no_local_exec_lock) 1328 rw_exit(&exec_lock); 1329 1330 pathbuf_stringcopy_put(data->ed_pathbuf, data->ed_pathstring); 1331 pathbuf_destroy(data->ed_pathbuf); 1332 PNBUF_PUT(data->ed_resolvedpathbuf); 1333 1334 /* 1335 * the old process doesn't exist anymore. exit gracefully. 1336 * get rid of the (new) address space we have created, if any, get rid 1337 * of our namei data and vnode, and exit noting failure 1338 */ 1339 uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, 1340 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); 1341 1342 exec_free_emul_arg(epp); 1343 pool_put(&exec_pool, data->ed_argp); 1344 kmem_free(epp->ep_hdr, epp->ep_hdrlen); 1345 if (epp->ep_emul_root != NULL) 1346 vrele(epp->ep_emul_root); 1347 if (epp->ep_interp != NULL) 1348 vrele(epp->ep_interp); 1349 1350 /* Acquire the sched-state mutex (exit1() will release it). */ 1351 if (!is_spawn) { 1352 mutex_enter(p->p_lock); 1353 exit1(l, W_EXITCODE(error, SIGABRT)); 1354 } 1355 1356 return error; 1357 } 1358 1359 int 1360 execve1(struct lwp *l, const char *path, char * const *args, 1361 char * const *envs, execve_fetch_element_t fetch_element) 1362 { 1363 struct execve_data data; 1364 int error; 1365 1366 error = execve_loadvm(l, path, args, envs, fetch_element, &data); 1367 if (error) 1368 return error; 1369 error = execve_runproc(l, &data, false, false); 1370 return error; 1371 } 1372 1373 static size_t 1374 fromptrsz(const struct exec_package *epp) 1375 { 1376 return (epp->ep_flags & EXEC_FROM32) ? sizeof(int) : sizeof(char *); 1377 } 1378 1379 static size_t 1380 ptrsz(const struct exec_package *epp) 1381 { 1382 return (epp->ep_flags & EXEC_32) ? sizeof(int) : sizeof(char *); 1383 } 1384 1385 static size_t 1386 calcargs(struct execve_data * restrict data, const size_t argenvstrlen) 1387 { 1388 struct exec_package * const epp = &data->ed_pack; 1389 1390 const size_t nargenvptrs = 1391 1 + /* long argc */ 1392 data->ed_argc + /* char *argv[] */ 1393 1 + /* \0 */ 1394 data->ed_envc + /* char *env[] */ 1395 1 + /* \0 */ 1396 epp->ep_esch->es_arglen; /* auxinfo */ 1397 1398 return (nargenvptrs * ptrsz(epp)) + argenvstrlen; 1399 } 1400 1401 static size_t 1402 calcstack(struct execve_data * restrict data, const size_t gaplen) 1403 { 1404 struct exec_package * const epp = &data->ed_pack; 1405 1406 data->ed_szsigcode = epp->ep_esch->es_emul->e_esigcode - 1407 epp->ep_esch->es_emul->e_sigcode; 1408 1409 data->ed_ps_strings_sz = (epp->ep_flags & EXEC_32) ? 1410 sizeof(struct ps_strings32) : sizeof(struct ps_strings); 1411 1412 const size_t sigcode_psstr_sz = 1413 data->ed_szsigcode + /* sigcode */ 1414 data->ed_ps_strings_sz + /* ps_strings */ 1415 STACK_PTHREADSPACE; /* pthread space */ 1416 1417 const size_t stacklen = 1418 data->ed_argslen + 1419 gaplen + 1420 sigcode_psstr_sz; 1421 1422 /* make the stack "safely" aligned */ 1423 return STACK_LEN_ALIGN(stacklen, STACK_ALIGNBYTES); 1424 } 1425 1426 static int 1427 copyoutargs(struct execve_data * restrict data, struct lwp *l, 1428 char * const newstack) 1429 { 1430 struct exec_package * const epp = &data->ed_pack; 1431 struct proc *p = l->l_proc; 1432 int error; 1433 1434 /* remember information about the process */ 1435 data->ed_arginfo.ps_nargvstr = data->ed_argc; 1436 data->ed_arginfo.ps_nenvstr = data->ed_envc; 1437 1438 /* 1439 * Allocate the stack address passed to the newly execve()'ed process. 1440 * 1441 * The new stack address will be set to the SP (stack pointer) register 1442 * in setregs(). 1443 */ 1444 1445 char *newargs = STACK_ALLOC( 1446 STACK_SHRINK(newstack, data->ed_argslen), data->ed_argslen); 1447 1448 error = (*epp->ep_esch->es_copyargs)(l, epp, 1449 &data->ed_arginfo, &newargs, data->ed_argp); 1450 1451 if (epp->ep_path) { 1452 PNBUF_PUT(epp->ep_path); 1453 epp->ep_path = NULL; 1454 } 1455 if (error) { 1456 DPRINTF(("%s: copyargs failed %d\n", __func__, error)); 1457 return error; 1458 } 1459 1460 error = copyoutpsstrs(data, p); 1461 if (error != 0) 1462 return error; 1463 1464 return 0; 1465 } 1466 1467 static int 1468 copyoutpsstrs(struct execve_data * restrict data, struct proc *p) 1469 { 1470 struct exec_package * const epp = &data->ed_pack; 1471 struct ps_strings32 arginfo32; 1472 void *aip; 1473 int error; 1474 1475 /* fill process ps_strings info */ 1476 p->p_psstrp = (vaddr_t)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr, 1477 STACK_PTHREADSPACE), data->ed_ps_strings_sz); 1478 1479 if (epp->ep_flags & EXEC_32) { 1480 aip = &arginfo32; 1481 arginfo32.ps_argvstr = (vaddr_t)data->ed_arginfo.ps_argvstr; 1482 arginfo32.ps_nargvstr = data->ed_arginfo.ps_nargvstr; 1483 arginfo32.ps_envstr = (vaddr_t)data->ed_arginfo.ps_envstr; 1484 arginfo32.ps_nenvstr = data->ed_arginfo.ps_nenvstr; 1485 } else 1486 aip = &data->ed_arginfo; 1487 1488 /* copy out the process's ps_strings structure */ 1489 if ((error = copyout(aip, (void *)p->p_psstrp, data->ed_ps_strings_sz)) 1490 != 0) { 1491 DPRINTF(("%s: ps_strings copyout %p->%p size %zu failed\n", 1492 __func__, aip, (void *)p->p_psstrp, data->ed_ps_strings_sz)); 1493 return error; 1494 } 1495 1496 return 0; 1497 } 1498 1499 static int 1500 copyinargs(struct execve_data * restrict data, char * const *args, 1501 char * const *envs, execve_fetch_element_t fetch_element, char **dpp) 1502 { 1503 struct exec_package * const epp = &data->ed_pack; 1504 char *dp; 1505 size_t i; 1506 int error; 1507 1508 dp = *dpp; 1509 1510 data->ed_argc = 0; 1511 1512 /* copy the fake args list, if there's one, freeing it as we go */ 1513 if (epp->ep_flags & EXEC_HASARGL) { 1514 struct exec_fakearg *fa = epp->ep_fa; 1515 1516 while (fa->fa_arg != NULL) { 1517 const size_t maxlen = ARG_MAX - (dp - data->ed_argp); 1518 size_t len; 1519 1520 len = strlcpy(dp, fa->fa_arg, maxlen); 1521 /* Count NUL into len. */ 1522 if (len < maxlen) 1523 len++; 1524 else { 1525 while (fa->fa_arg != NULL) { 1526 kmem_free(fa->fa_arg, fa->fa_len); 1527 fa++; 1528 } 1529 kmem_free(epp->ep_fa, epp->ep_fa_len); 1530 epp->ep_flags &= ~EXEC_HASARGL; 1531 return E2BIG; 1532 } 1533 ktrexecarg(fa->fa_arg, len - 1); 1534 dp += len; 1535 1536 kmem_free(fa->fa_arg, fa->fa_len); 1537 fa++; 1538 data->ed_argc++; 1539 } 1540 kmem_free(epp->ep_fa, epp->ep_fa_len); 1541 epp->ep_flags &= ~EXEC_HASARGL; 1542 } 1543 1544 /* 1545 * Read and count argument strings from user. 1546 */ 1547 1548 if (args == NULL) { 1549 DPRINTF(("%s: null args\n", __func__)); 1550 return EINVAL; 1551 } 1552 if (epp->ep_flags & EXEC_SKIPARG) 1553 args = (const void *)((const char *)args + fromptrsz(epp)); 1554 i = 0; 1555 error = copyinargstrs(data, args, fetch_element, &dp, &i, ktr_execarg); 1556 if (error != 0) { 1557 DPRINTF(("%s: copyin arg %d\n", __func__, error)); 1558 return error; 1559 } 1560 data->ed_argc += i; 1561 1562 /* 1563 * Read and count environment strings from user. 1564 */ 1565 1566 data->ed_envc = 0; 1567 /* environment need not be there */ 1568 if (envs == NULL) 1569 goto done; 1570 i = 0; 1571 error = copyinargstrs(data, envs, fetch_element, &dp, &i, ktr_execenv); 1572 if (error != 0) { 1573 DPRINTF(("%s: copyin env %d\n", __func__, error)); 1574 return error; 1575 } 1576 data->ed_envc += i; 1577 1578 done: 1579 *dpp = dp; 1580 1581 return 0; 1582 } 1583 1584 static int 1585 copyinargstrs(struct execve_data * restrict data, char * const *strs, 1586 execve_fetch_element_t fetch_element, char **dpp, size_t *ip, 1587 void (*ktr)(const void *, size_t)) 1588 { 1589 char *dp, *sp; 1590 size_t i; 1591 int error; 1592 1593 dp = *dpp; 1594 1595 i = 0; 1596 while (1) { 1597 const size_t maxlen = ARG_MAX - (dp - data->ed_argp); 1598 size_t len; 1599 1600 if ((error = (*fetch_element)(strs, i, &sp)) != 0) { 1601 return error; 1602 } 1603 if (!sp) 1604 break; 1605 if ((error = copyinstr(sp, dp, maxlen, &len)) != 0) { 1606 if (error == ENAMETOOLONG) 1607 error = E2BIG; 1608 return error; 1609 } 1610 if (__predict_false(ktrace_on)) 1611 (*ktr)(dp, len - 1); 1612 dp += len; 1613 i++; 1614 } 1615 1616 *dpp = dp; 1617 *ip = i; 1618 1619 return 0; 1620 } 1621 1622 /* 1623 * Copy argv and env strings from kernel buffer (argp) to the new stack. 1624 * Those strings are located just after auxinfo. 1625 */ 1626 int 1627 copyargs(struct lwp *l, struct exec_package *pack, struct ps_strings *arginfo, 1628 char **stackp, void *argp) 1629 { 1630 char **cpp, *dp, *sp; 1631 size_t len; 1632 void *nullp; 1633 long argc, envc; 1634 int error; 1635 1636 cpp = (char **)*stackp; 1637 nullp = NULL; 1638 argc = arginfo->ps_nargvstr; 1639 envc = arginfo->ps_nenvstr; 1640 1641 /* argc on stack is long */ 1642 CTASSERT(sizeof(*cpp) == sizeof(argc)); 1643 1644 dp = (char *)(cpp + 1645 1 + /* long argc */ 1646 argc + /* char *argv[] */ 1647 1 + /* \0 */ 1648 envc + /* char *env[] */ 1649 1 + /* \0 */ 1650 /* XXX auxinfo multiplied by ptr size? */ 1651 pack->ep_esch->es_arglen); /* auxinfo */ 1652 sp = argp; 1653 1654 if ((error = copyout(&argc, cpp++, sizeof(argc))) != 0) { 1655 COPYPRINTF("", cpp - 1, sizeof(argc)); 1656 return error; 1657 } 1658 1659 /* XXX don't copy them out, remap them! */ 1660 arginfo->ps_argvstr = cpp; /* remember location of argv for later */ 1661 1662 for (; --argc >= 0; sp += len, dp += len) { 1663 if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0) { 1664 COPYPRINTF("", cpp - 1, sizeof(dp)); 1665 return error; 1666 } 1667 if ((error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0) { 1668 COPYPRINTF("str", dp, (size_t)ARG_MAX); 1669 return error; 1670 } 1671 } 1672 1673 if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0) { 1674 COPYPRINTF("", cpp - 1, sizeof(nullp)); 1675 return error; 1676 } 1677 1678 arginfo->ps_envstr = cpp; /* remember location of envp for later */ 1679 1680 for (; --envc >= 0; sp += len, dp += len) { 1681 if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0) { 1682 COPYPRINTF("", cpp - 1, sizeof(dp)); 1683 return error; 1684 } 1685 if ((error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0) { 1686 COPYPRINTF("str", dp, (size_t)ARG_MAX); 1687 return error; 1688 } 1689 1690 } 1691 1692 if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0) { 1693 COPYPRINTF("", cpp - 1, sizeof(nullp)); 1694 return error; 1695 } 1696 1697 *stackp = (char *)cpp; 1698 return 0; 1699 } 1700 1701 1702 /* 1703 * Add execsw[] entries. 1704 */ 1705 int 1706 exec_add(struct execsw *esp, int count) 1707 { 1708 struct exec_entry *it; 1709 int i; 1710 1711 if (count == 0) { 1712 return 0; 1713 } 1714 1715 /* Check for duplicates. */ 1716 rw_enter(&exec_lock, RW_WRITER); 1717 for (i = 0; i < count; i++) { 1718 LIST_FOREACH(it, &ex_head, ex_list) { 1719 /* assume unique (makecmds, probe_func, emulation) */ 1720 if (it->ex_sw->es_makecmds == esp[i].es_makecmds && 1721 it->ex_sw->u.elf_probe_func == 1722 esp[i].u.elf_probe_func && 1723 it->ex_sw->es_emul == esp[i].es_emul) { 1724 rw_exit(&exec_lock); 1725 return EEXIST; 1726 } 1727 } 1728 } 1729 1730 /* Allocate new entries. */ 1731 for (i = 0; i < count; i++) { 1732 it = kmem_alloc(sizeof(*it), KM_SLEEP); 1733 it->ex_sw = &esp[i]; 1734 LIST_INSERT_HEAD(&ex_head, it, ex_list); 1735 } 1736 1737 /* update execsw[] */ 1738 exec_init(0); 1739 rw_exit(&exec_lock); 1740 return 0; 1741 } 1742 1743 /* 1744 * Remove execsw[] entry. 1745 */ 1746 int 1747 exec_remove(struct execsw *esp, int count) 1748 { 1749 struct exec_entry *it, *next; 1750 int i; 1751 const struct proclist_desc *pd; 1752 proc_t *p; 1753 1754 if (count == 0) { 1755 return 0; 1756 } 1757 1758 /* Abort if any are busy. */ 1759 rw_enter(&exec_lock, RW_WRITER); 1760 for (i = 0; i < count; i++) { 1761 mutex_enter(proc_lock); 1762 for (pd = proclists; pd->pd_list != NULL; pd++) { 1763 PROCLIST_FOREACH(p, pd->pd_list) { 1764 if (p->p_execsw == &esp[i]) { 1765 mutex_exit(proc_lock); 1766 rw_exit(&exec_lock); 1767 return EBUSY; 1768 } 1769 } 1770 } 1771 mutex_exit(proc_lock); 1772 } 1773 1774 /* None are busy, so remove them all. */ 1775 for (i = 0; i < count; i++) { 1776 for (it = LIST_FIRST(&ex_head); it != NULL; it = next) { 1777 next = LIST_NEXT(it, ex_list); 1778 if (it->ex_sw == &esp[i]) { 1779 LIST_REMOVE(it, ex_list); 1780 kmem_free(it, sizeof(*it)); 1781 break; 1782 } 1783 } 1784 } 1785 1786 /* update execsw[] */ 1787 exec_init(0); 1788 rw_exit(&exec_lock); 1789 return 0; 1790 } 1791 1792 /* 1793 * Initialize exec structures. If init_boot is true, also does necessary 1794 * one-time initialization (it's called from main() that way). 1795 * Once system is multiuser, this should be called with exec_lock held, 1796 * i.e. via exec_{add|remove}(). 1797 */ 1798 int 1799 exec_init(int init_boot) 1800 { 1801 const struct execsw **sw; 1802 struct exec_entry *ex; 1803 SLIST_HEAD(,exec_entry) first; 1804 SLIST_HEAD(,exec_entry) any; 1805 SLIST_HEAD(,exec_entry) last; 1806 int i, sz; 1807 1808 if (init_boot) { 1809 /* do one-time initializations */ 1810 rw_init(&exec_lock); 1811 mutex_init(&sigobject_lock, MUTEX_DEFAULT, IPL_NONE); 1812 pool_init(&exec_pool, NCARGS, 0, 0, PR_NOALIGN|PR_NOTOUCH, 1813 "execargs", &exec_palloc, IPL_NONE); 1814 pool_sethardlimit(&exec_pool, maxexec, "should not happen", 0); 1815 } else { 1816 KASSERT(rw_write_held(&exec_lock)); 1817 } 1818 1819 /* Sort each entry onto the appropriate queue. */ 1820 SLIST_INIT(&first); 1821 SLIST_INIT(&any); 1822 SLIST_INIT(&last); 1823 sz = 0; 1824 LIST_FOREACH(ex, &ex_head, ex_list) { 1825 switch(ex->ex_sw->es_prio) { 1826 case EXECSW_PRIO_FIRST: 1827 SLIST_INSERT_HEAD(&first, ex, ex_slist); 1828 break; 1829 case EXECSW_PRIO_ANY: 1830 SLIST_INSERT_HEAD(&any, ex, ex_slist); 1831 break; 1832 case EXECSW_PRIO_LAST: 1833 SLIST_INSERT_HEAD(&last, ex, ex_slist); 1834 break; 1835 default: 1836 panic("%s", __func__); 1837 break; 1838 } 1839 sz++; 1840 } 1841 1842 /* 1843 * Create new execsw[]. Ensure we do not try a zero-sized 1844 * allocation. 1845 */ 1846 sw = kmem_alloc(sz * sizeof(struct execsw *) + 1, KM_SLEEP); 1847 i = 0; 1848 SLIST_FOREACH(ex, &first, ex_slist) { 1849 sw[i++] = ex->ex_sw; 1850 } 1851 SLIST_FOREACH(ex, &any, ex_slist) { 1852 sw[i++] = ex->ex_sw; 1853 } 1854 SLIST_FOREACH(ex, &last, ex_slist) { 1855 sw[i++] = ex->ex_sw; 1856 } 1857 1858 /* Replace old execsw[] and free used memory. */ 1859 if (execsw != NULL) { 1860 kmem_free(__UNCONST(execsw), 1861 nexecs * sizeof(struct execsw *) + 1); 1862 } 1863 execsw = sw; 1864 nexecs = sz; 1865 1866 /* Figure out the maximum size of an exec header. */ 1867 exec_maxhdrsz = sizeof(int); 1868 for (i = 0; i < nexecs; i++) { 1869 if (execsw[i]->es_hdrsz > exec_maxhdrsz) 1870 exec_maxhdrsz = execsw[i]->es_hdrsz; 1871 } 1872 1873 return 0; 1874 } 1875 1876 static int 1877 exec_sigcode_map(struct proc *p, const struct emul *e) 1878 { 1879 vaddr_t va; 1880 vsize_t sz; 1881 int error; 1882 struct uvm_object *uobj; 1883 1884 sz = (vaddr_t)e->e_esigcode - (vaddr_t)e->e_sigcode; 1885 1886 if (e->e_sigobject == NULL || sz == 0) { 1887 return 0; 1888 } 1889 1890 /* 1891 * If we don't have a sigobject for this emulation, create one. 1892 * 1893 * sigobject is an anonymous memory object (just like SYSV shared 1894 * memory) that we keep a permanent reference to and that we map 1895 * in all processes that need this sigcode. The creation is simple, 1896 * we create an object, add a permanent reference to it, map it in 1897 * kernel space, copy out the sigcode to it and unmap it. 1898 * We map it with PROT_READ|PROT_EXEC into the process just 1899 * the way sys_mmap() would map it. 1900 */ 1901 1902 uobj = *e->e_sigobject; 1903 if (uobj == NULL) { 1904 mutex_enter(&sigobject_lock); 1905 if ((uobj = *e->e_sigobject) == NULL) { 1906 uobj = uao_create(sz, 0); 1907 (*uobj->pgops->pgo_reference)(uobj); 1908 va = vm_map_min(kernel_map); 1909 if ((error = uvm_map(kernel_map, &va, round_page(sz), 1910 uobj, 0, 0, 1911 UVM_MAPFLAG(UVM_PROT_RW, UVM_PROT_RW, 1912 UVM_INH_SHARE, UVM_ADV_RANDOM, 0)))) { 1913 printf("kernel mapping failed %d\n", error); 1914 (*uobj->pgops->pgo_detach)(uobj); 1915 mutex_exit(&sigobject_lock); 1916 return error; 1917 } 1918 memcpy((void *)va, e->e_sigcode, sz); 1919 #ifdef PMAP_NEED_PROCWR 1920 pmap_procwr(&proc0, va, sz); 1921 #endif 1922 uvm_unmap(kernel_map, va, va + round_page(sz)); 1923 *e->e_sigobject = uobj; 1924 } 1925 mutex_exit(&sigobject_lock); 1926 } 1927 1928 /* Just a hint to uvm_map where to put it. */ 1929 va = e->e_vm_default_addr(p, (vaddr_t)p->p_vmspace->vm_daddr, 1930 round_page(sz), p->p_vmspace->vm_map.flags & VM_MAP_TOPDOWN); 1931 1932 #ifdef __alpha__ 1933 /* 1934 * Tru64 puts /sbin/loader at the end of user virtual memory, 1935 * which causes the above calculation to put the sigcode at 1936 * an invalid address. Put it just below the text instead. 1937 */ 1938 if (va == (vaddr_t)vm_map_max(&p->p_vmspace->vm_map)) { 1939 va = (vaddr_t)p->p_vmspace->vm_taddr - round_page(sz); 1940 } 1941 #endif 1942 1943 (*uobj->pgops->pgo_reference)(uobj); 1944 error = uvm_map(&p->p_vmspace->vm_map, &va, round_page(sz), 1945 uobj, 0, 0, 1946 UVM_MAPFLAG(UVM_PROT_RX, UVM_PROT_RX, UVM_INH_SHARE, 1947 UVM_ADV_RANDOM, 0)); 1948 if (error) { 1949 DPRINTF(("%s, %d: map %p " 1950 "uvm_map %#"PRIxVSIZE"@%#"PRIxVADDR" failed %d\n", 1951 __func__, __LINE__, &p->p_vmspace->vm_map, round_page(sz), 1952 va, error)); 1953 (*uobj->pgops->pgo_detach)(uobj); 1954 return error; 1955 } 1956 p->p_sigctx.ps_sigcode = (void *)va; 1957 return 0; 1958 } 1959 1960 /* 1961 * Release a refcount on spawn_exec_data and destroy memory, if this 1962 * was the last one. 1963 */ 1964 static void 1965 spawn_exec_data_release(struct spawn_exec_data *data) 1966 { 1967 if (atomic_dec_32_nv(&data->sed_refcnt) != 0) 1968 return; 1969 1970 cv_destroy(&data->sed_cv_child_ready); 1971 mutex_destroy(&data->sed_mtx_child); 1972 1973 if (data->sed_actions) 1974 posix_spawn_fa_free(data->sed_actions, 1975 data->sed_actions->len); 1976 if (data->sed_attrs) 1977 kmem_free(data->sed_attrs, 1978 sizeof(*data->sed_attrs)); 1979 kmem_free(data, sizeof(*data)); 1980 } 1981 1982 /* 1983 * A child lwp of a posix_spawn operation starts here and ends up in 1984 * cpu_spawn_return, dealing with all filedescriptor and scheduler 1985 * manipulations in between. 1986 * The parent waits for the child, as it is not clear whether the child 1987 * will be able to acquire its own exec_lock. If it can, the parent can 1988 * be released early and continue running in parallel. If not (or if the 1989 * magic debug flag is passed in the scheduler attribute struct), the 1990 * child rides on the parent's exec lock until it is ready to return to 1991 * to userland - and only then releases the parent. This method loses 1992 * concurrency, but improves error reporting. 1993 */ 1994 static void 1995 spawn_return(void *arg) 1996 { 1997 struct spawn_exec_data *spawn_data = arg; 1998 struct lwp *l = curlwp; 1999 int error, newfd; 2000 int ostat; 2001 size_t i; 2002 const struct posix_spawn_file_actions_entry *fae; 2003 pid_t ppid; 2004 register_t retval; 2005 bool have_reflock; 2006 bool parent_is_waiting = true; 2007 2008 /* 2009 * Check if we can release parent early. 2010 * We either need to have no sed_attrs, or sed_attrs does not 2011 * have POSIX_SPAWN_RETURNERROR or one of the flags, that require 2012 * safe access to the parent proc (passed in sed_parent). 2013 * We then try to get the exec_lock, and only if that works, we can 2014 * release the parent here already. 2015 */ 2016 ppid = spawn_data->sed_parent->p_pid; 2017 if ((!spawn_data->sed_attrs 2018 || (spawn_data->sed_attrs->sa_flags 2019 & (POSIX_SPAWN_RETURNERROR|POSIX_SPAWN_SETPGROUP)) == 0) 2020 && rw_tryenter(&exec_lock, RW_READER)) { 2021 parent_is_waiting = false; 2022 mutex_enter(&spawn_data->sed_mtx_child); 2023 cv_signal(&spawn_data->sed_cv_child_ready); 2024 mutex_exit(&spawn_data->sed_mtx_child); 2025 } 2026 2027 /* don't allow debugger access yet */ 2028 rw_enter(&l->l_proc->p_reflock, RW_WRITER); 2029 have_reflock = true; 2030 2031 error = 0; 2032 /* handle posix_spawn_file_actions */ 2033 if (spawn_data->sed_actions != NULL) { 2034 for (i = 0; i < spawn_data->sed_actions->len; i++) { 2035 fae = &spawn_data->sed_actions->fae[i]; 2036 switch (fae->fae_action) { 2037 case FAE_OPEN: 2038 if (fd_getfile(fae->fae_fildes) != NULL) { 2039 error = fd_close(fae->fae_fildes); 2040 if (error) 2041 break; 2042 } 2043 error = fd_open(fae->fae_path, fae->fae_oflag, 2044 fae->fae_mode, &newfd); 2045 if (error) 2046 break; 2047 if (newfd != fae->fae_fildes) { 2048 error = dodup(l, newfd, 2049 fae->fae_fildes, 0, &retval); 2050 if (fd_getfile(newfd) != NULL) 2051 fd_close(newfd); 2052 } 2053 break; 2054 case FAE_DUP2: 2055 error = dodup(l, fae->fae_fildes, 2056 fae->fae_newfildes, 0, &retval); 2057 break; 2058 case FAE_CLOSE: 2059 if (fd_getfile(fae->fae_fildes) == NULL) { 2060 error = EBADF; 2061 break; 2062 } 2063 error = fd_close(fae->fae_fildes); 2064 break; 2065 } 2066 if (error) 2067 goto report_error; 2068 } 2069 } 2070 2071 /* handle posix_spawnattr */ 2072 if (spawn_data->sed_attrs != NULL) { 2073 struct sigaction sigact; 2074 sigact._sa_u._sa_handler = SIG_DFL; 2075 sigact.sa_flags = 0; 2076 2077 /* 2078 * set state to SSTOP so that this proc can be found by pid. 2079 * see proc_enterprp, do_sched_setparam below 2080 */ 2081 mutex_enter(proc_lock); 2082 /* 2083 * p_stat should be SACTIVE, so we need to adjust the 2084 * parent's p_nstopchild here. For safety, just make 2085 * we're on the good side of SDEAD before we adjust. 2086 */ 2087 ostat = l->l_proc->p_stat; 2088 KASSERT(ostat < SSTOP); 2089 l->l_proc->p_stat = SSTOP; 2090 l->l_proc->p_waited = 0; 2091 l->l_proc->p_pptr->p_nstopchild++; 2092 mutex_exit(proc_lock); 2093 2094 /* Set process group */ 2095 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETPGROUP) { 2096 pid_t mypid = l->l_proc->p_pid, 2097 pgrp = spawn_data->sed_attrs->sa_pgroup; 2098 2099 if (pgrp == 0) 2100 pgrp = mypid; 2101 2102 error = proc_enterpgrp(spawn_data->sed_parent, 2103 mypid, pgrp, false); 2104 if (error) 2105 goto report_error_stopped; 2106 } 2107 2108 /* Set scheduler policy */ 2109 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETSCHEDULER) 2110 error = do_sched_setparam(l->l_proc->p_pid, 0, 2111 spawn_data->sed_attrs->sa_schedpolicy, 2112 &spawn_data->sed_attrs->sa_schedparam); 2113 else if (spawn_data->sed_attrs->sa_flags 2114 & POSIX_SPAWN_SETSCHEDPARAM) { 2115 error = do_sched_setparam(ppid, 0, 2116 SCHED_NONE, &spawn_data->sed_attrs->sa_schedparam); 2117 } 2118 if (error) 2119 goto report_error_stopped; 2120 2121 /* Reset user ID's */ 2122 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_RESETIDS) { 2123 error = do_setresuid(l, -1, 2124 kauth_cred_getgid(l->l_cred), -1, 2125 ID_E_EQ_R | ID_E_EQ_S); 2126 if (error) 2127 goto report_error_stopped; 2128 error = do_setresuid(l, -1, 2129 kauth_cred_getuid(l->l_cred), -1, 2130 ID_E_EQ_R | ID_E_EQ_S); 2131 if (error) 2132 goto report_error_stopped; 2133 } 2134 2135 /* Set signal masks/defaults */ 2136 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETSIGMASK) { 2137 mutex_enter(l->l_proc->p_lock); 2138 error = sigprocmask1(l, SIG_SETMASK, 2139 &spawn_data->sed_attrs->sa_sigmask, NULL); 2140 mutex_exit(l->l_proc->p_lock); 2141 if (error) 2142 goto report_error_stopped; 2143 } 2144 2145 if (spawn_data->sed_attrs->sa_flags & POSIX_SPAWN_SETSIGDEF) { 2146 /* 2147 * The following sigaction call is using a sigaction 2148 * version 0 trampoline which is in the compatibility 2149 * code only. This is not a problem because for SIG_DFL 2150 * and SIG_IGN, the trampolines are now ignored. If they 2151 * were not, this would be a problem because we are 2152 * holding the exec_lock, and the compat code needs 2153 * to do the same in order to replace the trampoline 2154 * code of the process. 2155 */ 2156 for (i = 1; i <= NSIG; i++) { 2157 if (sigismember( 2158 &spawn_data->sed_attrs->sa_sigdefault, i)) 2159 sigaction1(l, i, &sigact, NULL, NULL, 2160 0); 2161 } 2162 } 2163 mutex_enter(proc_lock); 2164 l->l_proc->p_stat = ostat; 2165 l->l_proc->p_pptr->p_nstopchild--; 2166 mutex_exit(proc_lock); 2167 } 2168 2169 /* now do the real exec */ 2170 error = execve_runproc(l, &spawn_data->sed_exec, parent_is_waiting, 2171 true); 2172 have_reflock = false; 2173 if (error == EJUSTRETURN) 2174 error = 0; 2175 else if (error) 2176 goto report_error; 2177 2178 if (parent_is_waiting) { 2179 mutex_enter(&spawn_data->sed_mtx_child); 2180 cv_signal(&spawn_data->sed_cv_child_ready); 2181 mutex_exit(&spawn_data->sed_mtx_child); 2182 } 2183 2184 /* release our refcount on the data */ 2185 spawn_exec_data_release(spawn_data); 2186 2187 /* and finally: leave to userland for the first time */ 2188 cpu_spawn_return(l); 2189 2190 /* NOTREACHED */ 2191 return; 2192 2193 report_error_stopped: 2194 mutex_enter(proc_lock); 2195 l->l_proc->p_stat = ostat; 2196 l->l_proc->p_pptr->p_nstopchild--; 2197 mutex_exit(proc_lock); 2198 report_error: 2199 if (have_reflock) { 2200 /* 2201 * We have not passed through execve_runproc(), 2202 * which would have released the p_reflock and also 2203 * taken ownership of the sed_exec part of spawn_data, 2204 * so release/free both here. 2205 */ 2206 rw_exit(&l->l_proc->p_reflock); 2207 execve_free_data(&spawn_data->sed_exec); 2208 } 2209 2210 if (parent_is_waiting) { 2211 /* pass error to parent */ 2212 mutex_enter(&spawn_data->sed_mtx_child); 2213 spawn_data->sed_error = error; 2214 cv_signal(&spawn_data->sed_cv_child_ready); 2215 mutex_exit(&spawn_data->sed_mtx_child); 2216 } else { 2217 rw_exit(&exec_lock); 2218 } 2219 2220 /* release our refcount on the data */ 2221 spawn_exec_data_release(spawn_data); 2222 2223 /* done, exit */ 2224 mutex_enter(l->l_proc->p_lock); 2225 /* 2226 * Posix explicitly asks for an exit code of 127 if we report 2227 * errors from the child process - so, unfortunately, there 2228 * is no way to report a more exact error code. 2229 * A NetBSD specific workaround is POSIX_SPAWN_RETURNERROR as 2230 * flag bit in the attrp argument to posix_spawn(2), see above. 2231 */ 2232 exit1(l, W_EXITCODE(127, 0)); 2233 } 2234 2235 void 2236 posix_spawn_fa_free(struct posix_spawn_file_actions *fa, size_t len) 2237 { 2238 2239 for (size_t i = 0; i < len; i++) { 2240 struct posix_spawn_file_actions_entry *fae = &fa->fae[i]; 2241 if (fae->fae_action != FAE_OPEN) 2242 continue; 2243 kmem_free(fae->fae_path, strlen(fae->fae_path) + 1); 2244 } 2245 if (fa->len > 0) 2246 kmem_free(fa->fae, sizeof(*fa->fae) * fa->len); 2247 kmem_free(fa, sizeof(*fa)); 2248 } 2249 2250 static int 2251 posix_spawn_fa_alloc(struct posix_spawn_file_actions **fap, 2252 const struct posix_spawn_file_actions *ufa, rlim_t lim) 2253 { 2254 struct posix_spawn_file_actions *fa; 2255 struct posix_spawn_file_actions_entry *fae; 2256 char *pbuf = NULL; 2257 int error; 2258 size_t i = 0; 2259 2260 fa = kmem_alloc(sizeof(*fa), KM_SLEEP); 2261 error = copyin(ufa, fa, sizeof(*fa)); 2262 if (error || fa->len == 0) { 2263 kmem_free(fa, sizeof(*fa)); 2264 return error; /* 0 if not an error, and len == 0 */ 2265 } 2266 2267 if (fa->len > lim) { 2268 kmem_free(fa, sizeof(*fa)); 2269 return EINVAL; 2270 } 2271 2272 fa->size = fa->len; 2273 size_t fal = fa->len * sizeof(*fae); 2274 fae = fa->fae; 2275 fa->fae = kmem_alloc(fal, KM_SLEEP); 2276 error = copyin(fae, fa->fae, fal); 2277 if (error) 2278 goto out; 2279 2280 pbuf = PNBUF_GET(); 2281 for (; i < fa->len; i++) { 2282 fae = &fa->fae[i]; 2283 if (fae->fae_action != FAE_OPEN) 2284 continue; 2285 error = copyinstr(fae->fae_path, pbuf, MAXPATHLEN, &fal); 2286 if (error) 2287 goto out; 2288 fae->fae_path = kmem_alloc(fal, KM_SLEEP); 2289 memcpy(fae->fae_path, pbuf, fal); 2290 } 2291 PNBUF_PUT(pbuf); 2292 2293 *fap = fa; 2294 return 0; 2295 out: 2296 if (pbuf) 2297 PNBUF_PUT(pbuf); 2298 posix_spawn_fa_free(fa, i); 2299 return error; 2300 } 2301 2302 int 2303 check_posix_spawn(struct lwp *l1) 2304 { 2305 int error, tnprocs, count; 2306 uid_t uid; 2307 struct proc *p1; 2308 2309 p1 = l1->l_proc; 2310 uid = kauth_cred_getuid(l1->l_cred); 2311 tnprocs = atomic_inc_uint_nv(&nprocs); 2312 2313 /* 2314 * Although process entries are dynamically created, we still keep 2315 * a global limit on the maximum number we will create. 2316 */ 2317 if (__predict_false(tnprocs >= maxproc)) 2318 error = -1; 2319 else 2320 error = kauth_authorize_process(l1->l_cred, 2321 KAUTH_PROCESS_FORK, p1, KAUTH_ARG(tnprocs), NULL, NULL); 2322 2323 if (error) { 2324 atomic_dec_uint(&nprocs); 2325 return EAGAIN; 2326 } 2327 2328 /* 2329 * Enforce limits. 2330 */ 2331 count = chgproccnt(uid, 1); 2332 if (kauth_authorize_process(l1->l_cred, KAUTH_PROCESS_RLIMIT, 2333 p1, KAUTH_ARG(KAUTH_REQ_PROCESS_RLIMIT_BYPASS), 2334 &p1->p_rlimit[RLIMIT_NPROC], KAUTH_ARG(RLIMIT_NPROC)) != 0 && 2335 __predict_false(count > p1->p_rlimit[RLIMIT_NPROC].rlim_cur)) { 2336 (void)chgproccnt(uid, -1); 2337 atomic_dec_uint(&nprocs); 2338 return EAGAIN; 2339 } 2340 2341 return 0; 2342 } 2343 2344 int 2345 do_posix_spawn(struct lwp *l1, pid_t *pid_res, bool *child_ok, const char *path, 2346 struct posix_spawn_file_actions *fa, 2347 struct posix_spawnattr *sa, 2348 char *const *argv, char *const *envp, 2349 execve_fetch_element_t fetch) 2350 { 2351 2352 struct proc *p1, *p2; 2353 struct lwp *l2; 2354 int error; 2355 struct spawn_exec_data *spawn_data; 2356 vaddr_t uaddr; 2357 pid_t pid; 2358 bool have_exec_lock = false; 2359 2360 p1 = l1->l_proc; 2361 2362 /* Allocate and init spawn_data */ 2363 spawn_data = kmem_zalloc(sizeof(*spawn_data), KM_SLEEP); 2364 spawn_data->sed_refcnt = 1; /* only parent so far */ 2365 cv_init(&spawn_data->sed_cv_child_ready, "pspawn"); 2366 mutex_init(&spawn_data->sed_mtx_child, MUTEX_DEFAULT, IPL_NONE); 2367 mutex_enter(&spawn_data->sed_mtx_child); 2368 2369 /* 2370 * Do the first part of the exec now, collect state 2371 * in spawn_data. 2372 */ 2373 error = execve_loadvm(l1, path, argv, 2374 envp, fetch, &spawn_data->sed_exec); 2375 if (error == EJUSTRETURN) 2376 error = 0; 2377 else if (error) 2378 goto error_exit; 2379 2380 have_exec_lock = true; 2381 2382 /* 2383 * Allocate virtual address space for the U-area now, while it 2384 * is still easy to abort the fork operation if we're out of 2385 * kernel virtual address space. 2386 */ 2387 uaddr = uvm_uarea_alloc(); 2388 if (__predict_false(uaddr == 0)) { 2389 error = ENOMEM; 2390 goto error_exit; 2391 } 2392 2393 /* 2394 * Allocate new proc. Borrow proc0 vmspace for it, we will 2395 * replace it with its own before returning to userland 2396 * in the child. 2397 * This is a point of no return, we will have to go through 2398 * the child proc to properly clean it up past this point. 2399 */ 2400 p2 = proc_alloc(); 2401 pid = p2->p_pid; 2402 2403 /* 2404 * Make a proc table entry for the new process. 2405 * Start by zeroing the section of proc that is zero-initialized, 2406 * then copy the section that is copied directly from the parent. 2407 */ 2408 memset(&p2->p_startzero, 0, 2409 (unsigned) ((char *)&p2->p_endzero - (char *)&p2->p_startzero)); 2410 memcpy(&p2->p_startcopy, &p1->p_startcopy, 2411 (unsigned) ((char *)&p2->p_endcopy - (char *)&p2->p_startcopy)); 2412 p2->p_vmspace = proc0.p_vmspace; 2413 2414 TAILQ_INIT(&p2->p_sigpend.sp_info); 2415 2416 LIST_INIT(&p2->p_lwps); 2417 LIST_INIT(&p2->p_sigwaiters); 2418 2419 /* 2420 * Duplicate sub-structures as needed. 2421 * Increase reference counts on shared objects. 2422 * Inherit flags we want to keep. The flags related to SIGCHLD 2423 * handling are important in order to keep a consistent behaviour 2424 * for the child after the fork. If we are a 32-bit process, the 2425 * child will be too. 2426 */ 2427 p2->p_flag = 2428 p1->p_flag & (PK_SUGID | PK_NOCLDWAIT | PK_CLDSIGIGN | PK_32); 2429 p2->p_emul = p1->p_emul; 2430 p2->p_execsw = p1->p_execsw; 2431 2432 mutex_init(&p2->p_stmutex, MUTEX_DEFAULT, IPL_HIGH); 2433 mutex_init(&p2->p_auxlock, MUTEX_DEFAULT, IPL_NONE); 2434 rw_init(&p2->p_reflock); 2435 cv_init(&p2->p_waitcv, "wait"); 2436 cv_init(&p2->p_lwpcv, "lwpwait"); 2437 2438 p2->p_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE); 2439 2440 kauth_proc_fork(p1, p2); 2441 2442 p2->p_raslist = NULL; 2443 p2->p_fd = fd_copy(); 2444 2445 /* XXX racy */ 2446 p2->p_mqueue_cnt = p1->p_mqueue_cnt; 2447 2448 p2->p_cwdi = cwdinit(); 2449 2450 /* 2451 * Note: p_limit (rlimit stuff) is copy-on-write, so normally 2452 * we just need increase pl_refcnt. 2453 */ 2454 if (!p1->p_limit->pl_writeable) { 2455 lim_addref(p1->p_limit); 2456 p2->p_limit = p1->p_limit; 2457 } else { 2458 p2->p_limit = lim_copy(p1->p_limit); 2459 } 2460 2461 p2->p_lflag = 0; 2462 p2->p_sflag = 0; 2463 p2->p_slflag = 0; 2464 p2->p_pptr = p1; 2465 p2->p_ppid = p1->p_pid; 2466 LIST_INIT(&p2->p_children); 2467 2468 p2->p_aio = NULL; 2469 2470 #ifdef KTRACE 2471 /* 2472 * Copy traceflag and tracefile if enabled. 2473 * If not inherited, these were zeroed above. 2474 */ 2475 if (p1->p_traceflag & KTRFAC_INHERIT) { 2476 mutex_enter(&ktrace_lock); 2477 p2->p_traceflag = p1->p_traceflag; 2478 if ((p2->p_tracep = p1->p_tracep) != NULL) 2479 ktradref(p2); 2480 mutex_exit(&ktrace_lock); 2481 } 2482 #endif 2483 2484 /* 2485 * Create signal actions for the child process. 2486 */ 2487 p2->p_sigacts = sigactsinit(p1, 0); 2488 mutex_enter(p1->p_lock); 2489 p2->p_sflag |= 2490 (p1->p_sflag & (PS_STOPFORK | PS_STOPEXEC | PS_NOCLDSTOP)); 2491 sched_proc_fork(p1, p2); 2492 mutex_exit(p1->p_lock); 2493 2494 p2->p_stflag = p1->p_stflag; 2495 2496 /* 2497 * p_stats. 2498 * Copy parts of p_stats, and zero out the rest. 2499 */ 2500 p2->p_stats = pstatscopy(p1->p_stats); 2501 2502 /* copy over machdep flags to the new proc */ 2503 cpu_proc_fork(p1, p2); 2504 2505 /* 2506 * Prepare remaining parts of spawn data 2507 */ 2508 spawn_data->sed_actions = fa; 2509 spawn_data->sed_attrs = sa; 2510 2511 spawn_data->sed_parent = p1; 2512 2513 /* create LWP */ 2514 lwp_create(l1, p2, uaddr, 0, NULL, 0, spawn_return, spawn_data, 2515 &l2, l1->l_class); 2516 l2->l_ctxlink = NULL; /* reset ucontext link */ 2517 2518 /* 2519 * Copy the credential so other references don't see our changes. 2520 * Test to see if this is necessary first, since in the common case 2521 * we won't need a private reference. 2522 */ 2523 if (kauth_cred_geteuid(l2->l_cred) != kauth_cred_getsvuid(l2->l_cred) || 2524 kauth_cred_getegid(l2->l_cred) != kauth_cred_getsvgid(l2->l_cred)) { 2525 l2->l_cred = kauth_cred_copy(l2->l_cred); 2526 kauth_cred_setsvuid(l2->l_cred, kauth_cred_geteuid(l2->l_cred)); 2527 kauth_cred_setsvgid(l2->l_cred, kauth_cred_getegid(l2->l_cred)); 2528 } 2529 2530 /* Update the master credentials. */ 2531 if (l2->l_cred != p2->p_cred) { 2532 kauth_cred_t ocred; 2533 2534 kauth_cred_hold(l2->l_cred); 2535 mutex_enter(p2->p_lock); 2536 ocred = p2->p_cred; 2537 p2->p_cred = l2->l_cred; 2538 mutex_exit(p2->p_lock); 2539 kauth_cred_free(ocred); 2540 } 2541 2542 *child_ok = true; 2543 spawn_data->sed_refcnt = 2; /* child gets it as well */ 2544 #if 0 2545 l2->l_nopreempt = 1; /* start it non-preemptable */ 2546 #endif 2547 2548 /* 2549 * It's now safe for the scheduler and other processes to see the 2550 * child process. 2551 */ 2552 mutex_enter(proc_lock); 2553 2554 if (p1->p_session->s_ttyvp != NULL && p1->p_lflag & PL_CONTROLT) 2555 p2->p_lflag |= PL_CONTROLT; 2556 2557 LIST_INSERT_HEAD(&p1->p_children, p2, p_sibling); 2558 p2->p_exitsig = SIGCHLD; /* signal for parent on exit */ 2559 2560 LIST_INSERT_AFTER(p1, p2, p_pglist); 2561 LIST_INSERT_HEAD(&allproc, p2, p_list); 2562 2563 p2->p_trace_enabled = trace_is_enabled(p2); 2564 #ifdef __HAVE_SYSCALL_INTERN 2565 (*p2->p_emul->e_syscall_intern)(p2); 2566 #endif 2567 2568 /* 2569 * Make child runnable, set start time, and add to run queue except 2570 * if the parent requested the child to start in SSTOP state. 2571 */ 2572 mutex_enter(p2->p_lock); 2573 2574 getmicrotime(&p2->p_stats->p_start); 2575 2576 lwp_lock(l2); 2577 KASSERT(p2->p_nrlwps == 1); 2578 p2->p_nrlwps = 1; 2579 p2->p_stat = SACTIVE; 2580 l2->l_stat = LSRUN; 2581 sched_enqueue(l2, false); 2582 lwp_unlock(l2); 2583 2584 mutex_exit(p2->p_lock); 2585 mutex_exit(proc_lock); 2586 2587 cv_wait(&spawn_data->sed_cv_child_ready, &spawn_data->sed_mtx_child); 2588 error = spawn_data->sed_error; 2589 mutex_exit(&spawn_data->sed_mtx_child); 2590 spawn_exec_data_release(spawn_data); 2591 2592 rw_exit(&p1->p_reflock); 2593 rw_exit(&exec_lock); 2594 have_exec_lock = false; 2595 2596 *pid_res = pid; 2597 return error; 2598 2599 error_exit: 2600 if (have_exec_lock) { 2601 execve_free_data(&spawn_data->sed_exec); 2602 rw_exit(&p1->p_reflock); 2603 rw_exit(&exec_lock); 2604 } 2605 mutex_exit(&spawn_data->sed_mtx_child); 2606 spawn_exec_data_release(spawn_data); 2607 2608 return error; 2609 } 2610 2611 int 2612 sys_posix_spawn(struct lwp *l1, const struct sys_posix_spawn_args *uap, 2613 register_t *retval) 2614 { 2615 /* { 2616 syscallarg(pid_t *) pid; 2617 syscallarg(const char *) path; 2618 syscallarg(const struct posix_spawn_file_actions *) file_actions; 2619 syscallarg(const struct posix_spawnattr *) attrp; 2620 syscallarg(char *const *) argv; 2621 syscallarg(char *const *) envp; 2622 } */ 2623 2624 int error; 2625 struct posix_spawn_file_actions *fa = NULL; 2626 struct posix_spawnattr *sa = NULL; 2627 pid_t pid; 2628 bool child_ok = false; 2629 rlim_t max_fileactions; 2630 proc_t *p = l1->l_proc; 2631 2632 error = check_posix_spawn(l1); 2633 if (error) { 2634 *retval = error; 2635 return 0; 2636 } 2637 2638 /* copy in file_actions struct */ 2639 if (SCARG(uap, file_actions) != NULL) { 2640 max_fileactions = 2 * min(p->p_rlimit[RLIMIT_NOFILE].rlim_cur, 2641 maxfiles); 2642 error = posix_spawn_fa_alloc(&fa, SCARG(uap, file_actions), 2643 max_fileactions); 2644 if (error) 2645 goto error_exit; 2646 } 2647 2648 /* copyin posix_spawnattr struct */ 2649 if (SCARG(uap, attrp) != NULL) { 2650 sa = kmem_alloc(sizeof(*sa), KM_SLEEP); 2651 error = copyin(SCARG(uap, attrp), sa, sizeof(*sa)); 2652 if (error) 2653 goto error_exit; 2654 } 2655 2656 /* 2657 * Do the spawn 2658 */ 2659 error = do_posix_spawn(l1, &pid, &child_ok, SCARG(uap, path), fa, sa, 2660 SCARG(uap, argv), SCARG(uap, envp), execve_fetch_element); 2661 if (error) 2662 goto error_exit; 2663 2664 if (error == 0 && SCARG(uap, pid) != NULL) 2665 error = copyout(&pid, SCARG(uap, pid), sizeof(pid)); 2666 2667 *retval = error; 2668 return 0; 2669 2670 error_exit: 2671 if (!child_ok) { 2672 (void)chgproccnt(kauth_cred_getuid(l1->l_cred), -1); 2673 atomic_dec_uint(&nprocs); 2674 2675 if (sa) 2676 kmem_free(sa, sizeof(*sa)); 2677 if (fa) 2678 posix_spawn_fa_free(fa, fa->len); 2679 } 2680 2681 *retval = error; 2682 return 0; 2683 } 2684 2685 void 2686 exec_free_emul_arg(struct exec_package *epp) 2687 { 2688 if (epp->ep_emul_arg_free != NULL) { 2689 KASSERT(epp->ep_emul_arg != NULL); 2690 (*epp->ep_emul_arg_free)(epp->ep_emul_arg); 2691 epp->ep_emul_arg_free = NULL; 2692 epp->ep_emul_arg = NULL; 2693 } else { 2694 KASSERT(epp->ep_emul_arg == NULL); 2695 } 2696 } 2697 2698 #ifdef DEBUG_EXEC 2699 static void 2700 dump_vmcmds(const struct exec_package * const epp, size_t x, int error) 2701 { 2702 struct exec_vmcmd *vp = &epp->ep_vmcmds.evs_cmds[0]; 2703 size_t j; 2704 2705 if (error == 0) 2706 DPRINTF(("vmcmds %u\n", epp->ep_vmcmds.evs_used)); 2707 else 2708 DPRINTF(("vmcmds %zu/%u, error %d\n", x, 2709 epp->ep_vmcmds.evs_used, error)); 2710 2711 for (j = 0; j < epp->ep_vmcmds.evs_used; j++) { 2712 DPRINTF(("vmcmd[%zu] = vmcmd_map_%s %#" 2713 PRIxVADDR"/%#"PRIxVSIZE" fd@%#" 2714 PRIxVSIZE" prot=0%o flags=%d\n", j, 2715 vp[j].ev_proc == vmcmd_map_pagedvn ? 2716 "pagedvn" : 2717 vp[j].ev_proc == vmcmd_map_readvn ? 2718 "readvn" : 2719 vp[j].ev_proc == vmcmd_map_zero ? 2720 "zero" : "*unknown*", 2721 vp[j].ev_addr, vp[j].ev_len, 2722 vp[j].ev_offset, vp[j].ev_prot, 2723 vp[j].ev_flags)); 2724 if (error != 0 && j == x) 2725 DPRINTF((" ^--- failed\n")); 2726 } 2727 } 2728 #endif 2729