1 /* $NetBSD: exec_elf32.c,v 1.114 2006/05/18 17:35:49 elad 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 1.114 2006/05/18 17:35:49 elad 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 #ifdef _KERNEL_OPT 75 #include "opt_pax.h" 76 #endif /* _KERNEL_OPT */ 77 78 #include <sys/param.h> 79 #include <sys/proc.h> 80 #include <sys/malloc.h> 81 #include <sys/namei.h> 82 #include <sys/vnode.h> 83 #include <sys/exec.h> 84 #include <sys/exec_elf.h> 85 #include <sys/syscall.h> 86 #include <sys/signalvar.h> 87 #include <sys/mount.h> 88 #include <sys/stat.h> 89 #include <sys/kauth.h> 90 91 #include <machine/cpu.h> 92 #include <machine/reg.h> 93 94 #ifdef PAX_MPROTECT 95 #include <sys/pax.h> 96 #endif /* PAX_MPROTECT */ 97 98 extern const struct emul emul_netbsd; 99 100 #define elf_check_header ELFNAME(check_header) 101 #define elf_copyargs ELFNAME(copyargs) 102 #define elf_load_file ELFNAME(load_file) 103 #define elf_load_psection ELFNAME(load_psection) 104 #define exec_elf_makecmds ELFNAME2(exec,makecmds) 105 #define netbsd_elf_signature ELFNAME2(netbsd,signature) 106 #define netbsd_elf_probe ELFNAME2(netbsd,probe) 107 108 int elf_load_file(struct lwp *, struct exec_package *, char *, 109 struct exec_vmcmd_set *, u_long *, struct elf_args *, Elf_Addr *); 110 void elf_load_psection(struct exec_vmcmd_set *, struct vnode *, 111 const Elf_Phdr *, Elf_Addr *, u_long *, int *, int); 112 113 int netbsd_elf_signature(struct lwp *, struct exec_package *, Elf_Ehdr *); 114 int netbsd_elf_probe(struct lwp *, struct exec_package *, void *, char *, 115 vaddr_t *); 116 117 /* round up and down to page boundaries. */ 118 #define ELF_ROUND(a, b) (((a) + (b) - 1) & ~((b) - 1)) 119 #define ELF_TRUNC(a, b) ((a) & ~((b) - 1)) 120 121 #define MAXPHNUM 50 122 123 /* 124 * Copy arguments onto the stack in the normal way, but add some 125 * extra information in case of dynamic binding. 126 */ 127 int 128 elf_copyargs(struct lwp *l, struct exec_package *pack, 129 struct ps_strings *arginfo, char **stackp, void *argp) 130 { 131 size_t len; 132 AuxInfo ai[ELF_AUX_ENTRIES], *a; 133 struct elf_args *ap; 134 struct proc *p; 135 int error; 136 137 if ((error = copyargs(l, pack, arginfo, stackp, argp)) != 0) 138 return error; 139 140 a = ai; 141 p = l->l_proc; 142 143 /* 144 * Push extra arguments on the stack needed by dynamically 145 * linked binaries 146 */ 147 if ((ap = (struct elf_args *)pack->ep_emul_arg)) { 148 struct vattr *vap = pack->ep_vap; 149 150 a->a_type = AT_PHDR; 151 a->a_v = ap->arg_phaddr; 152 a++; 153 154 a->a_type = AT_PHENT; 155 a->a_v = ap->arg_phentsize; 156 a++; 157 158 a->a_type = AT_PHNUM; 159 a->a_v = ap->arg_phnum; 160 a++; 161 162 a->a_type = AT_PAGESZ; 163 a->a_v = PAGE_SIZE; 164 a++; 165 166 a->a_type = AT_BASE; 167 a->a_v = ap->arg_interp; 168 a++; 169 170 a->a_type = AT_FLAGS; 171 a->a_v = 0; 172 a++; 173 174 a->a_type = AT_ENTRY; 175 a->a_v = ap->arg_entry; 176 a++; 177 178 a->a_type = AT_EUID; 179 if (vap->va_mode & S_ISUID) 180 a->a_v = vap->va_uid; 181 else 182 a->a_v = kauth_cred_geteuid(p->p_cred); 183 a++; 184 185 a->a_type = AT_RUID; 186 a->a_v = kauth_cred_getuid(p->p_cred); 187 a++; 188 189 a->a_type = AT_EGID; 190 if (vap->va_mode & S_ISGID) 191 a->a_v = vap->va_gid; 192 else 193 a->a_v = kauth_cred_getegid(p->p_cred); 194 a++; 195 196 a->a_type = AT_RGID; 197 a->a_v = kauth_cred_getgid(p->p_cred); 198 a++; 199 200 free(ap, M_TEMP); 201 pack->ep_emul_arg = NULL; 202 } 203 204 a->a_type = AT_NULL; 205 a->a_v = 0; 206 a++; 207 208 len = (a - ai) * sizeof(AuxInfo); 209 if ((error = copyout(ai, *stackp, len)) != 0) 210 return error; 211 *stackp += len; 212 213 return 0; 214 } 215 216 /* 217 * elf_check_header(): 218 * 219 * Check header for validity; return 0 of ok ENOEXEC if error 220 */ 221 int 222 elf_check_header(Elf_Ehdr *eh, int type) 223 { 224 225 if (memcmp(eh->e_ident, ELFMAG, SELFMAG) != 0 || 226 eh->e_ident[EI_CLASS] != ELFCLASS) 227 return ENOEXEC; 228 229 switch (eh->e_machine) { 230 231 ELFDEFNNAME(MACHDEP_ID_CASES) 232 233 default: 234 return ENOEXEC; 235 } 236 237 if (ELF_EHDR_FLAGS_OK(eh) == 0) 238 return ENOEXEC; 239 240 if (eh->e_type != type) 241 return ENOEXEC; 242 243 if (eh->e_shnum > 32768 || eh->e_phnum > 128) 244 return ENOEXEC; 245 246 return 0; 247 } 248 249 /* 250 * elf_load_psection(): 251 * 252 * Load a psection at the appropriate address 253 */ 254 void 255 elf_load_psection(struct exec_vmcmd_set *vcset, struct vnode *vp, 256 const Elf_Phdr *ph, Elf_Addr *addr, u_long *size, int *prot, int flags) 257 { 258 u_long msize, psize, rm, rf; 259 long diff, offset; 260 261 /* 262 * If the user specified an address, then we load there. 263 */ 264 if (*addr == ELFDEFNNAME(NO_ADDR)) 265 *addr = ph->p_vaddr; 266 267 if (ph->p_align > 1) { 268 /* 269 * Make sure we are virtually aligned as we are supposed to be. 270 */ 271 diff = ph->p_vaddr - ELF_TRUNC(ph->p_vaddr, ph->p_align); 272 KASSERT(*addr - diff == ELF_TRUNC(*addr, ph->p_align)); 273 /* 274 * But make sure to not map any pages before the start of the 275 * psection by limiting the difference to within a page. 276 */ 277 diff &= PAGE_MASK; 278 } else 279 diff = 0; 280 281 *prot |= (ph->p_flags & PF_R) ? VM_PROT_READ : 0; 282 *prot |= (ph->p_flags & PF_W) ? VM_PROT_WRITE : 0; 283 *prot |= (ph->p_flags & PF_X) ? VM_PROT_EXECUTE : 0; 284 285 /* 286 * Adjust everything so it all starts on a page boundary. 287 */ 288 *addr -= diff; 289 offset = ph->p_offset - diff; 290 *size = ph->p_filesz + diff; 291 msize = ph->p_memsz + diff; 292 293 if (ph->p_align >= PAGE_SIZE) { 294 if ((ph->p_flags & PF_W) != 0) { 295 /* 296 * Because the pagedvn pager can't handle zero fill 297 * of the last data page if it's not page aligned we 298 * map the last page readvn. 299 */ 300 psize = trunc_page(*size); 301 } else { 302 psize = round_page(*size); 303 } 304 } else { 305 psize = *size; 306 } 307 308 if (psize > 0) { 309 NEW_VMCMD2(vcset, ph->p_align < PAGE_SIZE ? 310 vmcmd_map_readvn : vmcmd_map_pagedvn, psize, *addr, vp, 311 offset, *prot, flags); 312 flags &= VMCMD_RELATIVE; 313 } 314 if (psize < *size) { 315 NEW_VMCMD2(vcset, vmcmd_map_readvn, *size - psize, 316 *addr + psize, vp, offset + psize, *prot, flags); 317 } 318 319 /* 320 * Check if we need to extend the size of the segment (does 321 * bss extend page the next page boundary)? 322 */ 323 rm = round_page(*addr + msize); 324 rf = round_page(*addr + *size); 325 326 if (rm != rf) { 327 NEW_VMCMD2(vcset, vmcmd_map_zero, rm - rf, rf, NULLVP, 328 0, *prot, flags & VMCMD_RELATIVE); 329 *size = msize; 330 } 331 } 332 333 /* 334 * elf_load_file(): 335 * 336 * Load a file (interpreter/library) pointed to by path 337 * [stolen from coff_load_shlib()]. Made slightly generic 338 * so it might be used externally. 339 */ 340 int 341 elf_load_file(struct lwp *l, struct exec_package *epp, char *path, 342 struct exec_vmcmd_set *vcset, u_long *entryoff, struct elf_args *ap, 343 Elf_Addr *last) 344 { 345 int error, i; 346 struct nameidata nd; 347 struct vnode *vp; 348 struct vattr attr; 349 Elf_Ehdr eh; 350 Elf_Phdr *ph = NULL; 351 const Elf_Phdr *ph0; 352 const Elf_Phdr *base_ph; 353 const Elf_Phdr *last_ph; 354 u_long phsize; 355 Elf_Addr addr = *last; 356 struct proc *p; 357 358 p = l->l_proc; 359 360 /* 361 * 1. open file 362 * 2. read filehdr 363 * 3. map text, data, and bss out of it using VM_* 364 */ 365 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, path, l); 366 if ((error = namei(&nd)) != 0) 367 return error; 368 vp = nd.ni_vp; 369 370 /* 371 * Similarly, if it's not marked as executable, or it's not a regular 372 * file, we don't allow it to be used. 373 */ 374 if (vp->v_type != VREG) { 375 error = EACCES; 376 goto badunlock; 377 } 378 if ((error = VOP_ACCESS(vp, VEXEC, l->l_proc->p_cred, l)) != 0) 379 goto badunlock; 380 381 /* get attributes */ 382 if ((error = VOP_GETATTR(vp, &attr, l->l_proc->p_cred, l)) != 0) 383 goto badunlock; 384 385 /* 386 * Check mount point. Though we're not trying to exec this binary, 387 * we will be executing code from it, so if the mount point 388 * disallows execution or set-id-ness, we punt or kill the set-id. 389 */ 390 if (vp->v_mount->mnt_flag & MNT_NOEXEC) { 391 error = EACCES; 392 goto badunlock; 393 } 394 if (vp->v_mount->mnt_flag & MNT_NOSUID) 395 epp->ep_vap->va_mode &= ~(S_ISUID | S_ISGID); 396 397 #ifdef notyet /* XXX cgd 960926 */ 398 XXX cgd 960926: (maybe) VOP_OPEN it (and VOP_CLOSE in copyargs?) 399 #endif 400 401 error = vn_marktext(vp); 402 if (error) 403 goto badunlock; 404 405 VOP_UNLOCK(vp, 0); 406 407 if ((error = exec_read_from(l, vp, 0, &eh, sizeof(eh))) != 0) 408 goto bad; 409 410 if ((error = elf_check_header(&eh, ET_DYN)) != 0) 411 goto bad; 412 413 if (eh.e_phnum > MAXPHNUM) 414 goto bad; 415 416 phsize = eh.e_phnum * sizeof(Elf_Phdr); 417 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 418 419 if ((error = exec_read_from(l, vp, eh.e_phoff, ph, phsize)) != 0) 420 goto bad; 421 422 #ifdef ELF_INTERP_NON_RELOCATABLE 423 /* 424 * Evil hack: Only MIPS should be non-relocatable, and the 425 * psections should have a high address (typically 0x5ffe0000). 426 * If it's now relocatable, it should be linked at 0 and the 427 * psections should have zeros in the upper part of the address. 428 * Otherwise, force the load at the linked address. 429 */ 430 if (*last == ELF_LINK_ADDR && (ph->p_vaddr & 0xffff0000) == 0) 431 *last = ELFDEFNNAME(NO_ADDR); 432 #endif 433 434 /* 435 * If no position to load the interpreter was set by a probe 436 * function, pick the same address that a non-fixed mmap(0, ..) 437 * would (i.e. something safely out of the way). 438 */ 439 if (*last == ELFDEFNNAME(NO_ADDR)) { 440 u_long limit = 0; 441 /* 442 * Find the start and ending addresses of the psections to 443 * be loaded. This will give us the size. 444 */ 445 for (i = 0, ph0 = ph, base_ph = NULL; i < eh.e_phnum; 446 i++, ph0++) { 447 if (ph0->p_type == PT_LOAD) { 448 u_long psize = ph0->p_vaddr + ph0->p_memsz; 449 if (base_ph == NULL) 450 base_ph = ph0; 451 if (psize > limit) 452 limit = psize; 453 } 454 } 455 456 if (base_ph == NULL) { 457 error = ENOEXEC; 458 goto bad; 459 } 460 461 /* 462 * Now compute the size and load address. 463 */ 464 addr = (*epp->ep_esch->es_emul->e_vm_default_addr)(p, 465 epp->ep_daddr, 466 round_page(limit) - trunc_page(base_ph->p_vaddr)); 467 } else 468 addr = *last; /* may be ELF_LINK_ADDR */ 469 470 /* 471 * Load all the necessary sections 472 */ 473 for (i = 0, ph0 = ph, base_ph = NULL, last_ph = NULL; 474 i < eh.e_phnum; i++, ph0++) { 475 switch (ph0->p_type) { 476 case PT_LOAD: { 477 u_long size; 478 int prot = 0; 479 int flags; 480 481 if (base_ph == NULL) { 482 /* 483 * First encountered psection is always the 484 * base psection. Make sure it's aligned 485 * properly (align down for topdown and align 486 * upwards for not topdown). 487 */ 488 base_ph = ph0; 489 flags = VMCMD_BASE; 490 if (addr == ELF_LINK_ADDR) 491 addr = ph0->p_vaddr; 492 if (p->p_vmspace->vm_map.flags & VM_MAP_TOPDOWN) 493 addr = ELF_TRUNC(addr, ph0->p_align); 494 else 495 addr = ELF_ROUND(addr, ph0->p_align); 496 } else { 497 u_long limit = round_page(last_ph->p_vaddr 498 + last_ph->p_memsz); 499 u_long base = trunc_page(ph0->p_vaddr); 500 501 /* 502 * If there is a gap in between the psections, 503 * map it as inaccessible so nothing else 504 * mmap'ed will be placed there. 505 */ 506 if (limit != base) { 507 NEW_VMCMD2(vcset, vmcmd_map_zero, 508 base - limit, 509 limit - base_ph->p_vaddr, NULLVP, 510 0, VM_PROT_NONE, VMCMD_RELATIVE); 511 } 512 513 addr = ph0->p_vaddr - base_ph->p_vaddr; 514 flags = VMCMD_RELATIVE; 515 } 516 last_ph = ph0; 517 elf_load_psection(vcset, vp, &ph[i], &addr, 518 &size, &prot, flags); 519 /* 520 * If entry is within this psection then this 521 * must contain the .text section. *entryoff is 522 * relative to the base psection. 523 */ 524 if (eh.e_entry >= ph0->p_vaddr && 525 eh.e_entry < (ph0->p_vaddr + size)) { 526 *entryoff = eh.e_entry - base_ph->p_vaddr; 527 } 528 addr += size; 529 break; 530 } 531 532 case PT_DYNAMIC: 533 case PT_PHDR: 534 break; 535 536 case PT_NOTE: 537 #ifdef PAX_MPROTECT 538 pax_mprotect_adjust(l, ph[i].p_flags); 539 break; 540 #endif /* PAX_MPROTECT */ 541 542 default: 543 break; 544 } 545 } 546 547 free(ph, M_TEMP); 548 /* 549 * This value is ignored if TOPDOWN. 550 */ 551 *last = addr; 552 vrele(vp); 553 return 0; 554 555 badunlock: 556 VOP_UNLOCK(vp, 0); 557 558 bad: 559 if (ph != NULL) 560 free(ph, M_TEMP); 561 #ifdef notyet /* XXX cgd 960926 */ 562 (maybe) VOP_CLOSE it 563 #endif 564 vrele(vp); 565 return error; 566 } 567 568 /* 569 * exec_elf_makecmds(): Prepare an Elf binary's exec package 570 * 571 * First, set of the various offsets/lengths in the exec package. 572 * 573 * Then, mark the text image busy (so it can be demand paged) or error 574 * out if this is not possible. Finally, set up vmcmds for the 575 * text, data, bss, and stack segments. 576 */ 577 int 578 exec_elf_makecmds(struct lwp *l, struct exec_package *epp) 579 { 580 Elf_Ehdr *eh = epp->ep_hdr; 581 Elf_Phdr *ph, *pp; 582 Elf_Addr phdr = 0, pos = 0; 583 int error, i, nload; 584 char *interp = NULL; 585 u_long phsize; 586 struct proc *p; 587 588 if (epp->ep_hdrvalid < sizeof(Elf_Ehdr)) 589 return ENOEXEC; 590 591 /* 592 * XXX allow for executing shared objects. It seems silly 593 * but other ELF-based systems allow it as well. 594 */ 595 if (elf_check_header(eh, ET_EXEC) != 0 && 596 elf_check_header(eh, ET_DYN) != 0) 597 return ENOEXEC; 598 599 if (eh->e_phnum > MAXPHNUM) 600 return ENOEXEC; 601 602 error = vn_marktext(epp->ep_vp); 603 if (error) 604 return error; 605 606 /* 607 * Allocate space to hold all the program headers, and read them 608 * from the file 609 */ 610 p = l->l_proc; 611 phsize = eh->e_phnum * sizeof(Elf_Phdr); 612 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 613 614 if ((error = exec_read_from(l, epp->ep_vp, eh->e_phoff, ph, phsize)) != 615 0) 616 goto bad; 617 618 epp->ep_taddr = epp->ep_tsize = ELFDEFNNAME(NO_ADDR); 619 epp->ep_daddr = epp->ep_dsize = ELFDEFNNAME(NO_ADDR); 620 621 for (i = 0; i < eh->e_phnum; i++) { 622 pp = &ph[i]; 623 if (pp->p_type == PT_INTERP) { 624 if (pp->p_filesz >= MAXPATHLEN) 625 goto bad; 626 interp = PNBUF_GET(); 627 interp[0] = '\0'; 628 if ((error = exec_read_from(l, epp->ep_vp, 629 pp->p_offset, interp, pp->p_filesz)) != 0) 630 goto bad; 631 break; 632 } 633 } 634 635 /* 636 * On the same architecture, we may be emulating different systems. 637 * See which one will accept this executable. 638 * 639 * Probe functions would normally see if the interpreter (if any) 640 * exists. Emulation packages may possibly replace the interpreter in 641 * interp[] with a changed path (/emul/xxx/<path>). 642 */ 643 pos = ELFDEFNNAME(NO_ADDR); 644 if (epp->ep_esch->u.elf_probe_func) { 645 vaddr_t startp = (vaddr_t)pos; 646 647 error = (*epp->ep_esch->u.elf_probe_func)(l, epp, eh, interp, 648 &startp); 649 if (error) 650 goto bad; 651 pos = (Elf_Addr)startp; 652 } 653 654 /* 655 * Load all the necessary sections 656 */ 657 for (i = nload = 0; i < eh->e_phnum; i++) { 658 Elf_Addr addr = ELFDEFNNAME(NO_ADDR); 659 u_long size = 0; 660 int prot = 0; 661 662 pp = &ph[i]; 663 664 switch (ph[i].p_type) { 665 case PT_LOAD: 666 /* 667 * XXX 668 * Can handle only 2 sections: text and data 669 */ 670 if (nload++ == 2) 671 goto bad; 672 elf_load_psection(&epp->ep_vmcmds, epp->ep_vp, 673 &ph[i], &addr, &size, &prot, VMCMD_FIXED); 674 675 /* 676 * Decide whether it's text or data by looking 677 * at the entry point. 678 */ 679 if (eh->e_entry >= addr && 680 eh->e_entry < (addr + size)) { 681 epp->ep_taddr = addr; 682 epp->ep_tsize = size; 683 if (epp->ep_daddr == ELFDEFNNAME(NO_ADDR)) { 684 epp->ep_daddr = addr; 685 epp->ep_dsize = size; 686 } 687 } else { 688 epp->ep_daddr = addr; 689 epp->ep_dsize = size; 690 } 691 break; 692 693 case PT_SHLIB: 694 /* SCO has these sections. */ 695 case PT_INTERP: 696 /* Already did this one. */ 697 case PT_DYNAMIC: 698 case PT_NOTE: 699 break; 700 701 case PT_PHDR: 702 /* Note address of program headers (in text segment) */ 703 phdr = pp->p_vaddr; 704 break; 705 706 default: 707 /* 708 * Not fatal; we don't need to understand everything. 709 */ 710 break; 711 } 712 } 713 714 /* 715 * Check if we found a dynamically linked binary and arrange to load 716 * its interpreter 717 */ 718 if (interp) { 719 struct elf_args *ap; 720 int j = epp->ep_vmcmds.evs_used; 721 u_long interp_offset; 722 723 MALLOC(ap, struct elf_args *, sizeof(struct elf_args), 724 M_TEMP, M_WAITOK); 725 if ((error = elf_load_file(l, epp, interp, 726 &epp->ep_vmcmds, &interp_offset, ap, &pos)) != 0) { 727 FREE(ap, M_TEMP); 728 goto bad; 729 } 730 ap->arg_interp = epp->ep_vmcmds.evs_cmds[j].ev_addr; 731 epp->ep_entry = ap->arg_interp + interp_offset; 732 ap->arg_phaddr = phdr; 733 734 ap->arg_phentsize = eh->e_phentsize; 735 ap->arg_phnum = eh->e_phnum; 736 ap->arg_entry = eh->e_entry; 737 738 epp->ep_emul_arg = ap; 739 740 PNBUF_PUT(interp); 741 } else 742 epp->ep_entry = eh->e_entry; 743 744 #ifdef ELF_MAP_PAGE_ZERO 745 /* Dell SVR4 maps page zero, yeuch! */ 746 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, PAGE_SIZE, 0, 747 epp->ep_vp, 0, VM_PROT_READ); 748 #endif 749 free(ph, M_TEMP); 750 return (*epp->ep_esch->es_setup_stack)(l, epp); 751 752 bad: 753 if (interp) 754 PNBUF_PUT(interp); 755 free(ph, M_TEMP); 756 kill_vmcmds(&epp->ep_vmcmds); 757 return ENOEXEC; 758 } 759 760 int 761 netbsd_elf_signature(struct lwp *l, struct exec_package *epp, 762 Elf_Ehdr *eh) 763 { 764 size_t i; 765 Elf_Phdr *ph; 766 size_t phsize; 767 int error; 768 769 if (eh->e_phnum > MAXPHNUM) 770 return ENOEXEC; 771 772 phsize = eh->e_phnum * sizeof(Elf_Phdr); 773 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 774 error = exec_read_from(l, epp->ep_vp, eh->e_phoff, ph, phsize); 775 if (error) 776 goto out; 777 778 for (i = 0; i < eh->e_phnum; i++) { 779 Elf_Phdr *ephp = &ph[i]; 780 Elf_Nhdr *np; 781 782 if (ephp->p_type != PT_NOTE || 783 ephp->p_filesz > 1024 || 784 ephp->p_filesz < sizeof(Elf_Nhdr) + ELF_NOTE_NETBSD_NAMESZ) 785 continue; 786 787 np = (Elf_Nhdr *)malloc(ephp->p_filesz, M_TEMP, M_WAITOK); 788 error = exec_read_from(l, epp->ep_vp, ephp->p_offset, np, 789 ephp->p_filesz); 790 if (error) 791 goto next; 792 793 if (np->n_type != ELF_NOTE_TYPE_NETBSD_TAG || 794 np->n_namesz != ELF_NOTE_NETBSD_NAMESZ || 795 np->n_descsz != ELF_NOTE_NETBSD_DESCSZ || 796 memcmp((caddr_t)(np + 1), ELF_NOTE_NETBSD_NAME, 797 ELF_NOTE_NETBSD_NAMESZ)) 798 goto next; 799 800 error = 0; 801 free(np, M_TEMP); 802 goto out; 803 804 next: 805 free(np, M_TEMP); 806 continue; 807 } 808 809 error = ENOEXEC; 810 out: 811 free(ph, M_TEMP); 812 return error; 813 } 814 815 int 816 netbsd_elf_probe(struct lwp *l, struct exec_package *epp, 817 void *eh, char *itp, vaddr_t *pos) 818 { 819 int error; 820 821 if ((error = netbsd_elf_signature(l, epp, eh)) != 0) 822 return error; 823 #ifdef ELF_INTERP_NON_RELOCATABLE 824 *pos = ELF_LINK_ADDR; 825 #endif 826 return 0; 827 } 828