exec_elf32.c revision 1.111
1/* $NetBSD: exec_elf32.c,v 1.111 2006/03/17 11:03:07 skrll 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 1.111 2006/03/17 11:03:07 skrll 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 lwp *, 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 lwp *, struct exec_package *, Elf_Ehdr *); 105int netbsd_elf_probe(struct lwp *, 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 lwp *l, 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 struct proc *p; 126 int error; 127 128 if ((error = copyargs(l, pack, arginfo, stackp, argp)) != 0) 129 return error; 130 131 a = ai; 132 p = l->l_proc; 133 134 /* 135 * Push extra arguments on the stack needed by dynamically 136 * linked binaries 137 */ 138 if ((ap = (struct elf_args *)pack->ep_emul_arg)) { 139 struct vattr *vap = pack->ep_vap; 140 141 a->a_type = AT_PHDR; 142 a->a_v = ap->arg_phaddr; 143 a++; 144 145 a->a_type = AT_PHENT; 146 a->a_v = ap->arg_phentsize; 147 a++; 148 149 a->a_type = AT_PHNUM; 150 a->a_v = ap->arg_phnum; 151 a++; 152 153 a->a_type = AT_PAGESZ; 154 a->a_v = PAGE_SIZE; 155 a++; 156 157 a->a_type = AT_BASE; 158 a->a_v = ap->arg_interp; 159 a++; 160 161 a->a_type = AT_FLAGS; 162 a->a_v = 0; 163 a++; 164 165 a->a_type = AT_ENTRY; 166 a->a_v = ap->arg_entry; 167 a++; 168 169 a->a_type = AT_EUID; 170 if (vap->va_mode & S_ISUID) 171 a->a_v = vap->va_uid; 172 else 173 a->a_v = p->p_ucred->cr_uid; 174 a++; 175 176 a->a_type = AT_RUID; 177 a->a_v = p->p_cred->p_ruid; 178 a++; 179 180 a->a_type = AT_EGID; 181 if (vap->va_mode & S_ISGID) 182 a->a_v = vap->va_gid; 183 else 184 a->a_v = p->p_ucred->cr_gid; 185 a++; 186 187 a->a_type = AT_RGID; 188 a->a_v = p->p_cred->p_rgid; 189 a++; 190 191 free(ap, M_TEMP); 192 pack->ep_emul_arg = NULL; 193 } 194 195 a->a_type = AT_NULL; 196 a->a_v = 0; 197 a++; 198 199 len = (a - ai) * sizeof(AuxInfo); 200 if ((error = copyout(ai, *stackp, len)) != 0) 201 return error; 202 *stackp += len; 203 204 return 0; 205} 206 207/* 208 * elf_check_header(): 209 * 210 * Check header for validity; return 0 of ok ENOEXEC if error 211 */ 212int 213elf_check_header(Elf_Ehdr *eh, int type) 214{ 215 216 if (memcmp(eh->e_ident, ELFMAG, SELFMAG) != 0 || 217 eh->e_ident[EI_CLASS] != ELFCLASS) 218 return ENOEXEC; 219 220 switch (eh->e_machine) { 221 222 ELFDEFNNAME(MACHDEP_ID_CASES) 223 224 default: 225 return ENOEXEC; 226 } 227 228 if (ELF_EHDR_FLAGS_OK(eh) == 0) 229 return ENOEXEC; 230 231 if (eh->e_type != type) 232 return ENOEXEC; 233 234 if (eh->e_shnum > 32768 || eh->e_phnum > 128) 235 return ENOEXEC; 236 237 return 0; 238} 239 240/* 241 * elf_load_psection(): 242 * 243 * Load a psection at the appropriate address 244 */ 245void 246elf_load_psection(struct exec_vmcmd_set *vcset, struct vnode *vp, 247 const Elf_Phdr *ph, Elf_Addr *addr, u_long *size, int *prot, int flags) 248{ 249 u_long msize, psize, rm, rf; 250 long diff, offset; 251 252 /* 253 * If the user specified an address, then we load there. 254 */ 255 if (*addr == ELFDEFNNAME(NO_ADDR)) 256 *addr = ph->p_vaddr; 257 258 if (ph->p_align > 1) { 259 /* 260 * Make sure we are virtually aligned as we are supposed to be. 261 */ 262 diff = ph->p_vaddr - ELF_TRUNC(ph->p_vaddr, ph->p_align); 263 KASSERT(*addr - diff == ELF_TRUNC(*addr, ph->p_align)); 264 /* 265 * But make sure to not map any pages before the start of the 266 * psection by limiting the difference to within a page. 267 */ 268 diff &= PAGE_MASK; 269 } else 270 diff = 0; 271 272 *prot |= (ph->p_flags & PF_R) ? VM_PROT_READ : 0; 273 *prot |= (ph->p_flags & PF_W) ? VM_PROT_WRITE : 0; 274 *prot |= (ph->p_flags & PF_X) ? VM_PROT_EXECUTE : 0; 275 276 /* 277 * Adjust everything so it all starts on a page boundary. 278 */ 279 *addr -= diff; 280 offset = ph->p_offset - diff; 281 *size = ph->p_filesz + diff; 282 msize = ph->p_memsz + diff; 283 284 if (ph->p_align >= PAGE_SIZE) { 285 if ((ph->p_flags & PF_W) != 0) { 286 /* 287 * Because the pagedvn pager can't handle zero fill 288 * of the last data page if it's not page aligned we 289 * map the last page readvn. 290 */ 291 psize = trunc_page(*size); 292 } else { 293 psize = round_page(*size); 294 } 295 } else { 296 psize = *size; 297 } 298 299 if (psize > 0) { 300 NEW_VMCMD2(vcset, ph->p_align < PAGE_SIZE ? 301 vmcmd_map_readvn : vmcmd_map_pagedvn, psize, *addr, vp, 302 offset, *prot, flags); 303 flags &= VMCMD_RELATIVE; 304 } 305 if (psize < *size) { 306 NEW_VMCMD2(vcset, vmcmd_map_readvn, *size - psize, 307 *addr + psize, vp, offset + psize, *prot, flags); 308 } 309 310 /* 311 * Check if we need to extend the size of the segment (does 312 * bss extend page the next page boundary)? 313 */ 314 rm = round_page(*addr + msize); 315 rf = round_page(*addr + *size); 316 317 if (rm != rf) { 318 NEW_VMCMD2(vcset, vmcmd_map_zero, rm - rf, rf, NULLVP, 319 0, *prot, flags & VMCMD_RELATIVE); 320 *size = msize; 321 } 322} 323 324/* 325 * elf_load_file(): 326 * 327 * Load a file (interpreter/library) pointed to by path 328 * [stolen from coff_load_shlib()]. Made slightly generic 329 * so it might be used externally. 330 */ 331int 332elf_load_file(struct lwp *l, struct exec_package *epp, char *path, 333 struct exec_vmcmd_set *vcset, u_long *entryoff, struct elf_args *ap, 334 Elf_Addr *last) 335{ 336 int error, i; 337 struct nameidata nd; 338 struct vnode *vp; 339 struct vattr attr; 340 Elf_Ehdr eh; 341 Elf_Phdr *ph = NULL; 342 const Elf_Phdr *ph0; 343 const Elf_Phdr *base_ph; 344 const Elf_Phdr *last_ph; 345 u_long phsize; 346 Elf_Addr addr = *last; 347 struct proc *p; 348 349 p = l->l_proc; 350 351 /* 352 * 1. open file 353 * 2. read filehdr 354 * 3. map text, data, and bss out of it using VM_* 355 */ 356 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, path, l); 357 if ((error = namei(&nd)) != 0) 358 return error; 359 vp = nd.ni_vp; 360 361 /* 362 * Similarly, if it's not marked as executable, or it's not a regular 363 * file, we don't allow it to be used. 364 */ 365 if (vp->v_type != VREG) { 366 error = EACCES; 367 goto badunlock; 368 } 369 if ((error = VOP_ACCESS(vp, VEXEC, l->l_proc->p_ucred, l)) != 0) 370 goto badunlock; 371 372 /* get attributes */ 373 if ((error = VOP_GETATTR(vp, &attr, l->l_proc->p_ucred, l)) != 0) 374 goto badunlock; 375 376 /* 377 * Check mount point. Though we're not trying to exec this binary, 378 * we will be executing code from it, so if the mount point 379 * disallows execution or set-id-ness, we punt or kill the set-id. 380 */ 381 if (vp->v_mount->mnt_flag & MNT_NOEXEC) { 382 error = EACCES; 383 goto badunlock; 384 } 385 if (vp->v_mount->mnt_flag & MNT_NOSUID) 386 epp->ep_vap->va_mode &= ~(S_ISUID | S_ISGID); 387 388#ifdef notyet /* XXX cgd 960926 */ 389 XXX cgd 960926: (maybe) VOP_OPEN it (and VOP_CLOSE in copyargs?) 390#endif 391 392 error = vn_marktext(vp); 393 if (error) 394 goto badunlock; 395 396 VOP_UNLOCK(vp, 0); 397 398 if ((error = exec_read_from(l, vp, 0, &eh, sizeof(eh))) != 0) 399 goto bad; 400 401 if ((error = elf_check_header(&eh, ET_DYN)) != 0) 402 goto bad; 403 404 if (eh.e_phnum > MAXPHNUM) 405 goto bad; 406 407 phsize = eh.e_phnum * sizeof(Elf_Phdr); 408 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 409 410 if ((error = exec_read_from(l, vp, eh.e_phoff, ph, phsize)) != 0) 411 goto bad; 412 413#ifdef ELF_INTERP_NON_RELOCATABLE 414 /* 415 * Evil hack: Only MIPS should be non-relocatable, and the 416 * psections should have a high address (typically 0x5ffe0000). 417 * If it's now relocatable, it should be linked at 0 and the 418 * psections should have zeros in the upper part of the address. 419 * Otherwise, force the load at the linked address. 420 */ 421 if (*last == ELF_LINK_ADDR && (ph->p_vaddr & 0xffff0000) == 0) 422 *last = ELFDEFNNAME(NO_ADDR); 423#endif 424 425 /* 426 * If no position to load the interpreter was set by a probe 427 * function, pick the same address that a non-fixed mmap(0, ..) 428 * would (i.e. something safely out of the way). 429 */ 430 if (*last == ELFDEFNNAME(NO_ADDR)) { 431 u_long limit = 0; 432 /* 433 * Find the start and ending addresses of the psections to 434 * be loaded. This will give us the size. 435 */ 436 for (i = 0, ph0 = ph, base_ph = NULL; i < eh.e_phnum; 437 i++, ph0++) { 438 if (ph0->p_type == PT_LOAD) { 439 u_long psize = ph0->p_vaddr + ph0->p_memsz; 440 if (base_ph == NULL) 441 base_ph = ph0; 442 if (psize > limit) 443 limit = psize; 444 } 445 } 446 447 if (base_ph == NULL) { 448 error = ENOEXEC; 449 goto bad; 450 } 451 452 /* 453 * Now compute the size and load address. 454 */ 455 addr = (*epp->ep_esch->es_emul->e_vm_default_addr)(p, 456 epp->ep_daddr, 457 round_page(limit) - trunc_page(base_ph->p_vaddr)); 458 } else 459 addr = *last; /* may be ELF_LINK_ADDR */ 460 461 /* 462 * Load all the necessary sections 463 */ 464 for (i = 0, ph0 = ph, base_ph = NULL, last_ph = NULL; 465 i < eh.e_phnum; i++, ph0++) { 466 switch (ph0->p_type) { 467 case PT_LOAD: { 468 u_long size; 469 int prot = 0; 470 int flags; 471 472 if (base_ph == NULL) { 473 /* 474 * First encountered psection is always the 475 * base psection. Make sure it's aligned 476 * properly (align down for topdown and align 477 * upwards for not topdown). 478 */ 479 base_ph = ph0; 480 flags = VMCMD_BASE; 481 if (addr == ELF_LINK_ADDR) 482 addr = ph0->p_vaddr; 483 if (p->p_vmspace->vm_map.flags & VM_MAP_TOPDOWN) 484 addr = ELF_TRUNC(addr, ph0->p_align); 485 else 486 addr = ELF_ROUND(addr, ph0->p_align); 487 } else { 488 u_long limit = round_page(last_ph->p_vaddr 489 + last_ph->p_memsz); 490 u_long base = trunc_page(ph0->p_vaddr); 491 492 /* 493 * If there is a gap in between the psections, 494 * map it as inaccessible so nothing else 495 * mmap'ed will be placed there. 496 */ 497 if (limit != base) { 498 NEW_VMCMD2(vcset, vmcmd_map_zero, 499 base - limit, 500 limit - base_ph->p_vaddr, NULLVP, 501 0, VM_PROT_NONE, VMCMD_RELATIVE); 502 } 503 504 addr = ph0->p_vaddr - base_ph->p_vaddr; 505 flags = VMCMD_RELATIVE; 506 } 507 last_ph = ph0; 508 elf_load_psection(vcset, vp, &ph[i], &addr, 509 &size, &prot, flags); 510 /* 511 * If entry is within this psection then this 512 * must contain the .text section. *entryoff is 513 * relative to the base psection. 514 */ 515 if (eh.e_entry >= ph0->p_vaddr && 516 eh.e_entry < (ph0->p_vaddr + size)) { 517 *entryoff = eh.e_entry - base_ph->p_vaddr; 518 } 519 addr += size; 520 break; 521 } 522 523 case PT_DYNAMIC: 524 case PT_PHDR: 525 case PT_NOTE: 526 break; 527 528 default: 529 break; 530 } 531 } 532 533 free(ph, M_TEMP); 534 /* 535 * This value is ignored if TOPDOWN. 536 */ 537 *last = addr; 538 vrele(vp); 539 return 0; 540 541badunlock: 542 VOP_UNLOCK(vp, 0); 543 544bad: 545 if (ph != NULL) 546 free(ph, M_TEMP); 547#ifdef notyet /* XXX cgd 960926 */ 548 (maybe) VOP_CLOSE it 549#endif 550 vrele(vp); 551 return error; 552} 553 554/* 555 * exec_elf_makecmds(): Prepare an Elf binary's exec package 556 * 557 * First, set of the various offsets/lengths in the exec package. 558 * 559 * Then, mark the text image busy (so it can be demand paged) or error 560 * out if this is not possible. Finally, set up vmcmds for the 561 * text, data, bss, and stack segments. 562 */ 563int 564exec_elf_makecmds(struct lwp *l, struct exec_package *epp) 565{ 566 Elf_Ehdr *eh = epp->ep_hdr; 567 Elf_Phdr *ph, *pp; 568 Elf_Addr phdr = 0, pos = 0; 569 int error, i, nload; 570 char *interp = NULL; 571 u_long phsize; 572 struct proc *p; 573 574 if (epp->ep_hdrvalid < sizeof(Elf_Ehdr)) 575 return ENOEXEC; 576 577 /* 578 * XXX allow for executing shared objects. It seems silly 579 * but other ELF-based systems allow it as well. 580 */ 581 if (elf_check_header(eh, ET_EXEC) != 0 && 582 elf_check_header(eh, ET_DYN) != 0) 583 return ENOEXEC; 584 585 if (eh->e_phnum > MAXPHNUM) 586 return ENOEXEC; 587 588 error = vn_marktext(epp->ep_vp); 589 if (error) 590 return error; 591 592 /* 593 * Allocate space to hold all the program headers, and read them 594 * from the file 595 */ 596 p = l->l_proc; 597 phsize = eh->e_phnum * sizeof(Elf_Phdr); 598 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 599 600 if ((error = exec_read_from(l, epp->ep_vp, eh->e_phoff, ph, phsize)) != 601 0) 602 goto bad; 603 604 epp->ep_taddr = epp->ep_tsize = ELFDEFNNAME(NO_ADDR); 605 epp->ep_daddr = epp->ep_dsize = ELFDEFNNAME(NO_ADDR); 606 607 for (i = 0; i < eh->e_phnum; i++) { 608 pp = &ph[i]; 609 if (pp->p_type == PT_INTERP) { 610 if (pp->p_filesz >= MAXPATHLEN) 611 goto bad; 612 interp = PNBUF_GET(); 613 interp[0] = '\0'; 614 if ((error = exec_read_from(l, epp->ep_vp, 615 pp->p_offset, interp, pp->p_filesz)) != 0) 616 goto bad; 617 break; 618 } 619 } 620 621 /* 622 * On the same architecture, we may be emulating different systems. 623 * See which one will accept this executable. 624 * 625 * Probe functions would normally see if the interpreter (if any) 626 * exists. Emulation packages may possibly replace the interpreter in 627 * interp[] with a changed path (/emul/xxx/<path>). 628 */ 629 pos = ELFDEFNNAME(NO_ADDR); 630 if (epp->ep_esch->u.elf_probe_func) { 631 vaddr_t startp = (vaddr_t)pos; 632 633 error = (*epp->ep_esch->u.elf_probe_func)(l, epp, eh, interp, 634 &startp); 635 if (error) 636 goto bad; 637 pos = (Elf_Addr)startp; 638 } 639 640 /* 641 * Load all the necessary sections 642 */ 643 for (i = nload = 0; i < eh->e_phnum; i++) { 644 Elf_Addr addr = ELFDEFNNAME(NO_ADDR); 645 u_long size = 0; 646 int prot = 0; 647 648 pp = &ph[i]; 649 650 switch (ph[i].p_type) { 651 case PT_LOAD: 652 /* 653 * XXX 654 * Can handle only 2 sections: text and data 655 */ 656 if (nload++ == 2) 657 goto bad; 658 elf_load_psection(&epp->ep_vmcmds, epp->ep_vp, 659 &ph[i], &addr, &size, &prot, VMCMD_FIXED); 660 661 /* 662 * Decide whether it's text or data by looking 663 * at the entry point. 664 */ 665 if (eh->e_entry >= addr && 666 eh->e_entry < (addr + size)) { 667 epp->ep_taddr = addr; 668 epp->ep_tsize = size; 669 if (epp->ep_daddr == ELFDEFNNAME(NO_ADDR)) { 670 epp->ep_daddr = addr; 671 epp->ep_dsize = size; 672 } 673 } else { 674 epp->ep_daddr = addr; 675 epp->ep_dsize = size; 676 } 677 break; 678 679 case PT_SHLIB: 680 /* SCO has these sections. */ 681 case PT_INTERP: 682 /* Already did this one. */ 683 case PT_DYNAMIC: 684 case PT_NOTE: 685 break; 686 687 case PT_PHDR: 688 /* Note address of program headers (in text segment) */ 689 phdr = pp->p_vaddr; 690 break; 691 692 default: 693 /* 694 * Not fatal; we don't need to understand everything. 695 */ 696 break; 697 } 698 } 699 700 /* 701 * Check if we found a dynamically linked binary and arrange to load 702 * its interpreter 703 */ 704 if (interp) { 705 struct elf_args *ap; 706 int j = epp->ep_vmcmds.evs_used; 707 u_long interp_offset; 708 709 MALLOC(ap, struct elf_args *, sizeof(struct elf_args), 710 M_TEMP, M_WAITOK); 711 if ((error = elf_load_file(l, epp, interp, 712 &epp->ep_vmcmds, &interp_offset, ap, &pos)) != 0) { 713 FREE(ap, M_TEMP); 714 goto bad; 715 } 716 ap->arg_interp = epp->ep_vmcmds.evs_cmds[j].ev_addr; 717 epp->ep_entry = ap->arg_interp + interp_offset; 718 ap->arg_phaddr = phdr; 719 720 ap->arg_phentsize = eh->e_phentsize; 721 ap->arg_phnum = eh->e_phnum; 722 ap->arg_entry = eh->e_entry; 723 724 epp->ep_emul_arg = ap; 725 726 PNBUF_PUT(interp); 727 } else 728 epp->ep_entry = eh->e_entry; 729 730#ifdef ELF_MAP_PAGE_ZERO 731 /* Dell SVR4 maps page zero, yeuch! */ 732 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, PAGE_SIZE, 0, 733 epp->ep_vp, 0, VM_PROT_READ); 734#endif 735 free(ph, M_TEMP); 736 return (*epp->ep_esch->es_setup_stack)(l, epp); 737 738bad: 739 if (interp) 740 PNBUF_PUT(interp); 741 free(ph, M_TEMP); 742 kill_vmcmds(&epp->ep_vmcmds); 743 return ENOEXEC; 744} 745 746int 747netbsd_elf_signature(struct lwp *l, struct exec_package *epp, 748 Elf_Ehdr *eh) 749{ 750 size_t i; 751 Elf_Phdr *ph; 752 size_t phsize; 753 int error; 754 755 if (eh->e_phnum > MAXPHNUM) 756 return ENOEXEC; 757 758 phsize = eh->e_phnum * sizeof(Elf_Phdr); 759 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 760 error = exec_read_from(l, epp->ep_vp, eh->e_phoff, ph, phsize); 761 if (error) 762 goto out; 763 764 for (i = 0; i < eh->e_phnum; i++) { 765 Elf_Phdr *ephp = &ph[i]; 766 Elf_Nhdr *np; 767 768 if (ephp->p_type != PT_NOTE || 769 ephp->p_filesz > 1024 || 770 ephp->p_filesz < sizeof(Elf_Nhdr) + ELF_NOTE_NETBSD_NAMESZ) 771 continue; 772 773 np = (Elf_Nhdr *)malloc(ephp->p_filesz, M_TEMP, M_WAITOK); 774 error = exec_read_from(l, epp->ep_vp, ephp->p_offset, np, 775 ephp->p_filesz); 776 if (error) 777 goto next; 778 779 if (np->n_type != ELF_NOTE_TYPE_NETBSD_TAG || 780 np->n_namesz != ELF_NOTE_NETBSD_NAMESZ || 781 np->n_descsz != ELF_NOTE_NETBSD_DESCSZ || 782 memcmp((caddr_t)(np + 1), ELF_NOTE_NETBSD_NAME, 783 ELF_NOTE_NETBSD_NAMESZ)) 784 goto next; 785 786 error = 0; 787 free(np, M_TEMP); 788 goto out; 789 790 next: 791 free(np, M_TEMP); 792 continue; 793 } 794 795 error = ENOEXEC; 796out: 797 free(ph, M_TEMP); 798 return error; 799} 800 801int 802netbsd_elf_probe(struct lwp *l, struct exec_package *epp, 803 void *eh, char *itp, vaddr_t *pos) 804{ 805 int error; 806 807 if ((error = netbsd_elf_signature(l, epp, eh)) != 0) 808 return error; 809#ifdef ELF_INTERP_NON_RELOCATABLE 810 *pos = ELF_LINK_ADDR; 811#endif 812 return 0; 813} 814