exec_elf32.c revision 1.105
1/* $NetBSD: exec_elf32.c,v 1.105 2005/07/17 23:49:49 junyoung Exp $ */ 2 3/*- 4 * Copyright (c) 1994, 2000, 2005 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Christos Zoulas. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39/* 40 * Copyright (c) 1996 Christopher G. Demetriou 41 * All rights reserved. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. The name of the author may not be used to endorse or promote products 52 * derived from this software without specific prior written permission 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 55 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 56 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 57 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 58 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 59 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 60 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 61 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 62 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 63 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 64 */ 65 66#include <sys/cdefs.h> 67__KERNEL_RCSID(1, "$NetBSD: exec_elf32.c,v 1.105 2005/07/17 23:49:49 junyoung Exp $"); 68 69/* If not included by exec_elf64.c, ELFSIZE won't be defined. */ 70#ifndef ELFSIZE 71#define ELFSIZE 32 72#endif 73 74#include <sys/param.h> 75#include <sys/proc.h> 76#include <sys/malloc.h> 77#include <sys/namei.h> 78#include <sys/vnode.h> 79#include <sys/exec.h> 80#include <sys/exec_elf.h> 81#include <sys/syscall.h> 82#include <sys/signalvar.h> 83#include <sys/mount.h> 84#include <sys/stat.h> 85 86#include <machine/cpu.h> 87#include <machine/reg.h> 88 89extern const struct emul emul_netbsd; 90 91#define elf_check_header ELFNAME(check_header) 92#define elf_copyargs ELFNAME(copyargs) 93#define elf_load_file ELFNAME(load_file) 94#define elf_load_psection ELFNAME(load_psection) 95#define exec_elf_makecmds ELFNAME2(exec,makecmds) 96#define netbsd_elf_signature ELFNAME2(netbsd,signature) 97#define netbsd_elf_probe ELFNAME2(netbsd,probe) 98 99int elf_load_file(struct proc *, struct exec_package *, char *, 100 struct exec_vmcmd_set *, u_long *, struct elf_args *, Elf_Addr *); 101void elf_load_psection(struct exec_vmcmd_set *, struct vnode *, 102 const Elf_Phdr *, Elf_Addr *, u_long *, int *, int); 103 104int netbsd_elf_signature(struct proc *, struct exec_package *, Elf_Ehdr *); 105int netbsd_elf_probe(struct proc *, struct exec_package *, void *, char *, 106 vaddr_t *); 107 108/* round up and down to page boundaries. */ 109#define ELF_ROUND(a, b) (((a) + (b) - 1) & ~((b) - 1)) 110#define ELF_TRUNC(a, b) ((a) & ~((b) - 1)) 111 112#define MAXPHNUM 50 113 114/* 115 * Copy arguments onto the stack in the normal way, but add some 116 * extra information in case of dynamic binding. 117 */ 118int 119elf_copyargs(struct proc *p, struct exec_package *pack, 120 struct ps_strings *arginfo, char **stackp, void *argp) 121{ 122 size_t len; 123 AuxInfo ai[ELF_AUX_ENTRIES], *a; 124 struct elf_args *ap; 125 int error; 126 127 if ((error = copyargs(p, pack, arginfo, stackp, argp)) != 0) 128 return error; 129 130 a = ai; 131 132 /* 133 * Push extra arguments on the stack needed by dynamically 134 * linked binaries 135 */ 136 if ((ap = (struct elf_args *)pack->ep_emul_arg)) { 137 struct vattr *vap = pack->ep_vap; 138 139 a->a_type = AT_PHDR; 140 a->a_v = ap->arg_phaddr; 141 a++; 142 143 a->a_type = AT_PHENT; 144 a->a_v = ap->arg_phentsize; 145 a++; 146 147 a->a_type = AT_PHNUM; 148 a->a_v = ap->arg_phnum; 149 a++; 150 151 a->a_type = AT_PAGESZ; 152 a->a_v = PAGE_SIZE; 153 a++; 154 155 a->a_type = AT_BASE; 156 a->a_v = ap->arg_interp; 157 a++; 158 159 a->a_type = AT_FLAGS; 160 a->a_v = 0; 161 a++; 162 163 a->a_type = AT_ENTRY; 164 a->a_v = ap->arg_entry; 165 a++; 166 167 a->a_type = AT_EUID; 168 if (vap->va_mode & S_ISUID) 169 a->a_v = vap->va_uid; 170 else 171 a->a_v = p->p_ucred->cr_uid; 172 a++; 173 174 a->a_type = AT_RUID; 175 a->a_v = p->p_cred->p_ruid; 176 a++; 177 178 a->a_type = AT_EGID; 179 if (vap->va_mode & S_ISGID) 180 a->a_v = vap->va_gid; 181 else 182 a->a_v = p->p_ucred->cr_gid; 183 a++; 184 185 a->a_type = AT_RGID; 186 a->a_v = p->p_cred->p_rgid; 187 a++; 188 189 free(ap, M_TEMP); 190 pack->ep_emul_arg = NULL; 191 } 192 193 a->a_type = AT_NULL; 194 a->a_v = 0; 195 a++; 196 197 len = (a - ai) * sizeof(AuxInfo); 198 if ((error = copyout(ai, *stackp, len)) != 0) 199 return error; 200 *stackp += len; 201 202 return 0; 203} 204 205/* 206 * elf_check_header(): 207 * 208 * Check header for validity; return 0 of ok ENOEXEC if error 209 */ 210int 211elf_check_header(Elf_Ehdr *eh, int type) 212{ 213 214 if (memcmp(eh->e_ident, ELFMAG, SELFMAG) != 0 || 215 eh->e_ident[EI_CLASS] != ELFCLASS) 216 return (ENOEXEC); 217 218 switch (eh->e_machine) { 219 220 ELFDEFNNAME(MACHDEP_ID_CASES) 221 222 default: 223 return (ENOEXEC); 224 } 225 226 if (ELF_EHDR_FLAGS_OK(eh) == 0) 227 return (ENOEXEC); 228 229 if (eh->e_type != type) 230 return (ENOEXEC); 231 232 if (eh->e_shnum > 32768 || eh->e_phnum > 128) 233 return (ENOEXEC); 234 235 return (0); 236} 237 238/* 239 * elf_load_psection(): 240 * 241 * Load a psection at the appropriate address 242 */ 243void 244elf_load_psection(struct exec_vmcmd_set *vcset, struct vnode *vp, 245 const Elf_Phdr *ph, Elf_Addr *addr, u_long *size, int *prot, int flags) 246{ 247 u_long msize, psize, rm, rf; 248 long diff, offset; 249 250 /* 251 * If the user specified an address, then we load there. 252 */ 253 if (*addr == ELFDEFNNAME(NO_ADDR)) 254 *addr = ph->p_vaddr; 255 256 if (ph->p_align > 1) { 257 /* 258 * Make sure we are virtually aligned as we are supposed to be. 259 */ 260 diff = ph->p_vaddr - ELF_TRUNC(ph->p_vaddr, ph->p_align); 261 KASSERT(*addr - diff == ELF_TRUNC(*addr, ph->p_align)); 262 /* 263 * But make sure to not map any pages before the start of the 264 * psection by limiting the difference to within a page. 265 */ 266 diff &= PAGE_MASK; 267 } else 268 diff = 0; 269 270 *prot |= (ph->p_flags & PF_R) ? VM_PROT_READ : 0; 271 *prot |= (ph->p_flags & PF_W) ? VM_PROT_WRITE : 0; 272 *prot |= (ph->p_flags & PF_X) ? VM_PROT_EXECUTE : 0; 273 274 /* 275 * Adjust everything so it all starts on a page boundary. 276 */ 277 *addr -= diff; 278 offset = ph->p_offset - diff; 279 *size = ph->p_filesz + diff; 280 msize = ph->p_memsz + diff; 281 282 if (ph->p_align >= PAGE_SIZE) { 283 if ((ph->p_flags & PF_W) != 0) { 284 /* 285 * Because the pagedvn pager can't handle zero fill 286 * of the last data page if it's not page aligned we 287 * map the last page readvn. 288 */ 289 psize = trunc_page(*size); 290 } else { 291 psize = round_page(*size); 292 } 293 } else { 294 psize = *size; 295 } 296 297 if (psize > 0) { 298 NEW_VMCMD2(vcset, ph->p_align < PAGE_SIZE ? 299 vmcmd_map_readvn : vmcmd_map_pagedvn, psize, *addr, vp, 300 offset, *prot, flags); 301 flags &= VMCMD_RELATIVE; 302 } 303 if (psize < *size) { 304 NEW_VMCMD2(vcset, vmcmd_map_readvn, *size - psize, 305 *addr + psize, vp, offset + psize, *prot, flags); 306 } 307 308 /* 309 * Check if we need to extend the size of the segment (does 310 * bss extend page the next page boundary)? 311 */ 312 rm = round_page(*addr + msize); 313 rf = round_page(*addr + *size); 314 315 if (rm != rf) { 316 NEW_VMCMD2(vcset, vmcmd_map_zero, rm - rf, rf, NULLVP, 317 0, *prot, flags & VMCMD_RELATIVE); 318 *size = msize; 319 } 320} 321 322/* 323 * elf_load_file(): 324 * 325 * Load a file (interpreter/library) pointed to by path 326 * [stolen from coff_load_shlib()]. Made slightly generic 327 * so it might be used externally. 328 */ 329int 330elf_load_file(struct proc *p, struct exec_package *epp, char *path, 331 struct exec_vmcmd_set *vcset, u_long *entryoff, struct elf_args *ap, 332 Elf_Addr *last) 333{ 334 int error, i; 335 struct nameidata nd; 336 struct vnode *vp; 337 struct vattr attr; 338 Elf_Ehdr eh; 339 Elf_Phdr *ph = NULL; 340 const Elf_Phdr *ph0; 341 const Elf_Phdr *base_ph; 342 const Elf_Phdr *last_ph; 343 u_long phsize; 344 Elf_Addr addr = *last; 345 346 /* 347 * 1. open file 348 * 2. read filehdr 349 * 3. map text, data, and bss out of it using VM_* 350 */ 351 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, path, p); 352 if ((error = namei(&nd)) != 0) 353 return error; 354 vp = nd.ni_vp; 355 356 /* 357 * Similarly, if it's not marked as executable, or it's not a regular 358 * file, we don't allow it to be used. 359 */ 360 if (vp->v_type != VREG) { 361 error = EACCES; 362 goto badunlock; 363 } 364 if ((error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p)) != 0) 365 goto badunlock; 366 367 /* get attributes */ 368 if ((error = VOP_GETATTR(vp, &attr, p->p_ucred, p)) != 0) 369 goto badunlock; 370 371 /* 372 * Check mount point. Though we're not trying to exec this binary, 373 * we will be executing code from it, so if the mount point 374 * disallows execution or set-id-ness, we punt or kill the set-id. 375 */ 376 if (vp->v_mount->mnt_flag & MNT_NOEXEC) { 377 error = EACCES; 378 goto badunlock; 379 } 380 if (vp->v_mount->mnt_flag & MNT_NOSUID) 381 epp->ep_vap->va_mode &= ~(S_ISUID | S_ISGID); 382 383#ifdef notyet /* XXX cgd 960926 */ 384 XXX cgd 960926: (maybe) VOP_OPEN it (and VOP_CLOSE in copyargs?) 385#endif 386 387 error = vn_marktext(vp); 388 if (error) 389 goto badunlock; 390 391 VOP_UNLOCK(vp, 0); 392 393 if ((error = exec_read_from(p, vp, 0, &eh, sizeof(eh))) != 0) 394 goto bad; 395 396 if ((error = elf_check_header(&eh, ET_DYN)) != 0) 397 goto bad; 398 399 if (eh.e_phnum > MAXPHNUM) 400 goto bad; 401 402 phsize = eh.e_phnum * sizeof(Elf_Phdr); 403 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 404 405 if ((error = exec_read_from(p, vp, eh.e_phoff, ph, phsize)) != 0) 406 goto bad; 407 408 /* 409 * If no position to load the interpreter was set by a probe 410 * function, pick the same address that a non-fixed mmap(0, ..) 411 * would (i.e. something safely out of the way). 412 */ 413 if (*last == ELFDEFNNAME(NO_ADDR)) { 414 u_long limit = 0; 415 /* 416 * Find the start and ending addresses of the psections to 417 * be loaded. This will give us the size. 418 */ 419 for (i = 0, ph0 = ph, base_ph = NULL; i < eh.e_phnum; 420 i++, ph0++) { 421 if (ph0->p_type == PT_LOAD) { 422 u_long psize = ph0->p_vaddr + ph0->p_memsz; 423 if (base_ph == NULL) 424 base_ph = ph0; 425 if (psize > limit) 426 limit = psize; 427 } 428 } 429 430 /* 431 * Now compute the size and load address. 432 */ 433 addr = (*epp->ep_esch->es_emul->e_vm_default_addr)(p, 434 epp->ep_daddr, 435 round_page(limit) - trunc_page(base_ph->p_vaddr)); 436 } else 437 addr = *last; /* may be ELF_LINK_ADDR */ 438 439 /* 440 * Load all the necessary sections 441 */ 442 for (i = 0, ph0 = ph, base_ph = NULL, last_ph = NULL; 443 i < eh.e_phnum; i++, ph0++) { 444 switch (ph0->p_type) { 445 case PT_LOAD: { 446 u_long size; 447 int prot = 0; 448 int flags; 449 450 if (base_ph == NULL) { 451 /* 452 * First encountered psection is always the 453 * base psection. Make sure it's aligned 454 * properly (align down for topdown and align 455 * upwards for not topdown). 456 */ 457 base_ph = ph0; 458 flags = VMCMD_BASE; 459 if (addr == ELF_LINK_ADDR) 460 addr = ph0->p_vaddr; 461 if (p->p_vmspace->vm_map.flags & VM_MAP_TOPDOWN) 462 addr = ELF_TRUNC(addr, ph0->p_align); 463 else 464 addr = ELF_ROUND(addr, ph0->p_align); 465 } else { 466 u_long limit = round_page(last_ph->p_vaddr 467 + last_ph->p_memsz); 468 u_long base = trunc_page(ph0->p_vaddr); 469 470 /* 471 * If there is a gap in between the psections, 472 * map it as inaccessible so nothing else 473 * mmap'ed will be placed there. 474 */ 475 if (limit != base) { 476 NEW_VMCMD2(vcset, vmcmd_map_zero, 477 base - limit, 478 limit - base_ph->p_vaddr, NULLVP, 479 0, VM_PROT_NONE, VMCMD_RELATIVE); 480 } 481 482 addr = ph0->p_vaddr - base_ph->p_vaddr; 483 flags = VMCMD_RELATIVE; 484 } 485 last_ph = ph0; 486 elf_load_psection(vcset, vp, &ph[i], &addr, 487 &size, &prot, flags); 488 /* 489 * If entry is within this psection then this 490 * must contain the .text section. *entryoff is 491 * relative to the base psection. 492 */ 493 if (eh.e_entry >= ph0->p_vaddr && 494 eh.e_entry < (ph0->p_vaddr + size)) { 495 *entryoff = eh.e_entry - base_ph->p_vaddr; 496 } 497 addr += size; 498 break; 499 } 500 501 case PT_DYNAMIC: 502 case PT_PHDR: 503 case PT_NOTE: 504 break; 505 506 default: 507 break; 508 } 509 } 510 511 free(ph, M_TEMP); 512 /* 513 * This value is ignored if TOPDOWN. 514 */ 515 *last = addr; 516 vrele(vp); 517 return 0; 518 519badunlock: 520 VOP_UNLOCK(vp, 0); 521 522bad: 523 if (ph != NULL) 524 free(ph, M_TEMP); 525#ifdef notyet /* XXX cgd 960926 */ 526 (maybe) VOP_CLOSE it 527#endif 528 vrele(vp); 529 return error; 530} 531 532/* 533 * exec_elf_makecmds(): Prepare an Elf binary's exec package 534 * 535 * First, set of the various offsets/lengths in the exec package. 536 * 537 * Then, mark the text image busy (so it can be demand paged) or error 538 * out if this is not possible. Finally, set up vmcmds for the 539 * text, data, bss, and stack segments. 540 */ 541int 542exec_elf_makecmds(struct proc *p, struct exec_package *epp) 543{ 544 Elf_Ehdr *eh = epp->ep_hdr; 545 Elf_Phdr *ph, *pp; 546 Elf_Addr phdr = 0, pos = 0; 547 int error, i, nload; 548 char *interp = NULL; 549 u_long phsize; 550 551 if (epp->ep_hdrvalid < sizeof(Elf_Ehdr)) 552 return ENOEXEC; 553 554 /* 555 * XXX allow for executing shared objects. It seems silly 556 * but other ELF-based systems allow it as well. 557 */ 558 if (elf_check_header(eh, ET_EXEC) != 0 && 559 elf_check_header(eh, ET_DYN) != 0) 560 return ENOEXEC; 561 562 if (eh->e_phnum > MAXPHNUM) 563 return ENOEXEC; 564 565 error = vn_marktext(epp->ep_vp); 566 if (error) 567 return (error); 568 569 /* 570 * Allocate space to hold all the program headers, and read them 571 * from the file 572 */ 573 phsize = eh->e_phnum * sizeof(Elf_Phdr); 574 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 575 576 if ((error = exec_read_from(p, epp->ep_vp, eh->e_phoff, ph, phsize)) != 577 0) 578 goto bad; 579 580 epp->ep_taddr = epp->ep_tsize = ELFDEFNNAME(NO_ADDR); 581 epp->ep_daddr = epp->ep_dsize = ELFDEFNNAME(NO_ADDR); 582 583 for (i = 0; i < eh->e_phnum; i++) { 584 pp = &ph[i]; 585 if (pp->p_type == PT_INTERP) { 586 if (pp->p_filesz >= MAXPATHLEN) 587 goto bad; 588 MALLOC(interp, char *, MAXPATHLEN, M_TEMP, M_WAITOK); 589 interp[0] = '\0'; 590 if ((error = exec_read_from(p, epp->ep_vp, 591 pp->p_offset, interp, pp->p_filesz)) != 0) 592 goto bad; 593 break; 594 } 595 } 596 597 /* 598 * On the same architecture, we may be emulating different systems. 599 * See which one will accept this executable. 600 * 601 * Probe functions would normally see if the interpreter (if any) 602 * exists. Emulation packages may possibly replace the interpreter in 603 * interp[] with a changed path (/emul/xxx/<path>). 604 */ 605 pos = ELFDEFNNAME(NO_ADDR); 606 if (epp->ep_esch->u.elf_probe_func) { 607 vaddr_t startp = (vaddr_t)pos; 608 609 error = (*epp->ep_esch->u.elf_probe_func)(p, epp, eh, interp, 610 &startp); 611 if (error) 612 goto bad; 613 pos = (Elf_Addr)startp; 614 } 615 616 /* 617 * Load all the necessary sections 618 */ 619 for (i = nload = 0; i < eh->e_phnum; i++) { 620 Elf_Addr addr = ELFDEFNNAME(NO_ADDR); 621 u_long size = 0; 622 int prot = 0; 623 624 pp = &ph[i]; 625 626 switch (ph[i].p_type) { 627 case PT_LOAD: 628 /* 629 * XXX 630 * Can handle only 2 sections: text and data 631 */ 632 if (nload++ == 2) 633 goto bad; 634 elf_load_psection(&epp->ep_vmcmds, epp->ep_vp, 635 &ph[i], &addr, &size, &prot, VMCMD_FIXED); 636 637 /* 638 * Decide whether it's text or data by looking 639 * at the entry point. 640 */ 641 if (eh->e_entry >= addr && 642 eh->e_entry < (addr + size)) { 643 epp->ep_taddr = addr; 644 epp->ep_tsize = size; 645 if (epp->ep_daddr == ELFDEFNNAME(NO_ADDR)) { 646 epp->ep_daddr = addr; 647 epp->ep_dsize = size; 648 } 649 } else { 650 epp->ep_daddr = addr; 651 epp->ep_dsize = size; 652 } 653 break; 654 655 case PT_SHLIB: 656 /* SCO has these sections. */ 657 case PT_INTERP: 658 /* Already did this one. */ 659 case PT_DYNAMIC: 660 case PT_NOTE: 661 break; 662 663 case PT_PHDR: 664 /* Note address of program headers (in text segment) */ 665 phdr = pp->p_vaddr; 666 break; 667 668 default: 669 /* 670 * Not fatal; we don't need to understand everything. 671 */ 672 break; 673 } 674 } 675 676 /* 677 * Check if we found a dynamically linked binary and arrange to load 678 * its interpreter 679 */ 680 if (interp) { 681 struct elf_args *ap; 682 int j = epp->ep_vmcmds.evs_used; 683 u_long interp_offset; 684 685 MALLOC(ap, struct elf_args *, sizeof(struct elf_args), 686 M_TEMP, M_WAITOK); 687 if ((error = elf_load_file(p, epp, interp, 688 &epp->ep_vmcmds, &interp_offset, ap, &pos)) != 0) { 689 FREE(ap, M_TEMP); 690 goto bad; 691 } 692 ap->arg_interp = epp->ep_vmcmds.evs_cmds[j].ev_addr; 693 epp->ep_entry = ap->arg_interp + interp_offset; 694 ap->arg_phaddr = phdr; 695 696 ap->arg_phentsize = eh->e_phentsize; 697 ap->arg_phnum = eh->e_phnum; 698 ap->arg_entry = eh->e_entry; 699 700 epp->ep_emul_arg = ap; 701 702 FREE(interp, M_TEMP); 703 } else 704 epp->ep_entry = eh->e_entry; 705 706#ifdef ELF_MAP_PAGE_ZERO 707 /* Dell SVR4 maps page zero, yeuch! */ 708 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, PAGE_SIZE, 0, 709 epp->ep_vp, 0, VM_PROT_READ); 710#endif 711 free(ph, M_TEMP); 712 return (*epp->ep_esch->es_setup_stack)(p, epp); 713 714bad: 715 if (interp) 716 FREE(interp, M_TEMP); 717 free(ph, M_TEMP); 718 kill_vmcmds(&epp->ep_vmcmds); 719 return ENOEXEC; 720} 721 722int 723netbsd_elf_signature(struct proc *p, struct exec_package *epp, 724 Elf_Ehdr *eh) 725{ 726 size_t i; 727 Elf_Phdr *ph; 728 size_t phsize; 729 int error; 730 731 if (eh->e_phnum > MAXPHNUM) 732 return ENOEXEC; 733 734 phsize = eh->e_phnum * sizeof(Elf_Phdr); 735 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 736 error = exec_read_from(p, epp->ep_vp, eh->e_phoff, ph, phsize); 737 if (error) 738 goto out; 739 740 for (i = 0; i < eh->e_phnum; i++) { 741 Elf_Phdr *ephp = &ph[i]; 742 Elf_Nhdr *np; 743 744 if (ephp->p_type != PT_NOTE || 745 ephp->p_filesz > 1024 || 746 ephp->p_filesz < sizeof(Elf_Nhdr) + ELF_NOTE_NETBSD_NAMESZ) 747 continue; 748 749 np = (Elf_Nhdr *)malloc(ephp->p_filesz, M_TEMP, M_WAITOK); 750 error = exec_read_from(p, epp->ep_vp, ephp->p_offset, np, 751 ephp->p_filesz); 752 if (error) 753 goto next; 754 755 if (np->n_type != ELF_NOTE_TYPE_NETBSD_TAG || 756 np->n_namesz != ELF_NOTE_NETBSD_NAMESZ || 757 np->n_descsz != ELF_NOTE_NETBSD_DESCSZ || 758 memcmp((caddr_t)(np + 1), ELF_NOTE_NETBSD_NAME, 759 ELF_NOTE_NETBSD_NAMESZ)) 760 goto next; 761 762 error = 0; 763 free(np, M_TEMP); 764 goto out; 765 766 next: 767 free(np, M_TEMP); 768 continue; 769 } 770 771 error = ENOEXEC; 772out: 773 free(ph, M_TEMP); 774 return (error); 775} 776 777int 778netbsd_elf_probe(struct proc *p, struct exec_package *epp, 779 void *eh, char *itp, vaddr_t *pos) 780{ 781 int error; 782 783 if ((error = netbsd_elf_signature(p, epp, eh)) != 0) 784 return error; 785#ifdef ELF_INTERP_NON_RELOCATABLE 786 *pos = ELF_LINK_ADDR; 787#endif 788 return 0; 789} 790