1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright (c) 1988 AT&T 24 * All Rights Reserved 25 * 26 * Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved. 27 * 28 * Copyright 2011, Richard Lowe. 29 */ 30 31 /* 32 * This file contains the functions responsible for opening the output file 33 * image, associating the appropriate input elf structures with the new image, 34 * and obtaining new elf structures to define the new image. 35 */ 36 #include <stdio.h> 37 #include <sys/stat.h> 38 #include <fcntl.h> 39 #include <link.h> 40 #include <errno.h> 41 #include <string.h> 42 #include <limits.h> 43 #include <debug.h> 44 #include <unistd.h> 45 #include "msg.h" 46 #include "_libld.h" 47 48 /* 49 * Determine a least common multiplier. Input sections contain an alignment 50 * requirement, which elf_update() uses to insure that the section is aligned 51 * correctly off of the base of the elf image. We must also insure that the 52 * sections mapping is congruent with this alignment requirement. For each 53 * input section associated with a loadable segment determine whether the 54 * segments alignment must be adjusted to compensate for a sections alignment 55 * requirements. 56 */ 57 Xword 58 ld_lcm(Xword a, Xword b) 59 { 60 Xword _r, _a, _b; 61 62 if ((_a = a) == 0) 63 return (b); 64 if ((_b = b) == 0) 65 return (a); 66 67 if (_a > _b) 68 _a = b, _b = a; 69 while ((_r = _b % _a) != 0) 70 _b = _a, _a = _r; 71 return ((a / _a) * b); 72 } 73 74 /* 75 * Open the output file and insure the correct access modes. 76 */ 77 uintptr_t 78 ld_open_outfile(Ofl_desc * ofl) 79 { 80 mode_t mode; 81 struct stat status; 82 83 /* 84 * Determine the required file mode from the type of output file we 85 * are creating. 86 */ 87 mode = (ofl->ofl_flags & (FLG_OF_EXEC | FLG_OF_SHAROBJ)) 88 ? 0777 : 0666; 89 90 /* Determine if the output file already exists */ 91 if (stat(ofl->ofl_name, &status) == 0) { 92 if ((status.st_mode & S_IFMT) != S_IFREG) { 93 /* 94 * It is not a regular file, so don't delete it 95 * or allow it to be deleted. This allows root 96 * users to specify /dev/null output file for 97 * verification links. 98 */ 99 ofl->ofl_flags1 |= FLG_OF1_NONREG; 100 } else { 101 /* 102 * It's a regular file, so unlink it. In standard 103 * Unix fashion, the old file will continue to 104 * exist until its link count drops to 0 and no 105 * process has the file open. In the meantime, we 106 * create a new file (inode) under the same name, 107 * available for new use. 108 * 109 * The advantage of this policy is that creating 110 * a new executable or sharable library does not 111 * corrupt existing processes using the old file. 112 * A possible disadvantage is that if the existing 113 * file has a (link_count > 1), the other names will 114 * continue to reference the old inode, thus 115 * breaking the link. 116 * 117 * A subtlety here is that POSIX says we are not 118 * supposed to replace a non-writable file, which 119 * is something that unlink() is happy to do. The 120 * only 100% reliable test against this is to open 121 * the file for non-destructive write access. If the 122 * open succeeds, we are clear to unlink it, and if 123 * not, then the error generated is the error we 124 * need to report. 125 */ 126 if ((ofl->ofl_fd = open(ofl->ofl_name, O_RDWR, 127 mode)) < 0) { 128 int err = errno; 129 130 if (err != ENOENT) { 131 ld_eprintf(ofl, ERR_FATAL, 132 MSG_INTL(MSG_SYS_OPEN), 133 ofl->ofl_name, strerror(err)); 134 return (S_ERROR); 135 } 136 } else { 137 (void) close(ofl->ofl_fd); 138 } 139 140 if ((unlink(ofl->ofl_name) == -1) && 141 (errno != ENOENT)) { 142 int err = errno; 143 144 ld_eprintf(ofl, ERR_FATAL, 145 MSG_INTL(MSG_SYS_UNLINK), 146 ofl->ofl_name, strerror(err)); 147 return (S_ERROR); 148 } 149 } 150 } 151 152 /* 153 * Open (or create) the output file name (ofl_fd acts as a global 154 * flag to ldexit() signifying whether the output file should be 155 * removed or not on error). 156 */ 157 if ((ofl->ofl_fd = open(ofl->ofl_name, O_RDWR | O_CREAT | O_TRUNC, 158 mode)) < 0) { 159 int err = errno; 160 161 ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_SYS_OPEN), 162 ofl->ofl_name, strerror(err)); 163 return (S_ERROR); 164 } 165 166 return (1); 167 } 168 169 170 /* 171 * If we are creating a memory model we need to update the present memory image. 172 * Use elf_update(ELF_C_NULL) to calculate the offset of each section and their 173 * associated data buffers. From this information determine what padding is 174 * required. 175 * 176 * Two actions are necessary to convert the present disc image into a memory 177 * image: 178 * 179 * - Loadable segments must be padded so that the next segment virtual 180 * address and file offset are the same. 181 * 182 * - NOBITS sections must be converted into allocated, null filled sections. 183 */ 184 static uintptr_t 185 pad_outfile(Ofl_desc *ofl) 186 { 187 Aliste idx1; 188 off_t offset; 189 Elf_Scn *oscn = 0; 190 Sg_desc *sgp; 191 Ehdr *ehdr; 192 193 /* 194 * Update all the elf structures. This will assign offsets to the 195 * section headers and data buffers as they relate to the new image. 196 */ 197 if (elf_update(ofl->ofl_welf, ELF_C_NULL) == -1) { 198 ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_UPDATE), 199 ofl->ofl_name); 200 return (S_ERROR); 201 } 202 if ((ehdr = elf_getehdr(ofl->ofl_welf)) == NULL) { 203 ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_GETEHDR), 204 ofl->ofl_name); 205 return (S_ERROR); 206 } 207 208 /* 209 * Initialize the offset by skipping the Elf header and program 210 * headers. 211 */ 212 offset = ehdr->e_phoff + (ehdr->e_phnum * ehdr->e_phentsize); 213 214 /* 215 * Traverse the segment list looking for loadable segments. 216 */ 217 for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) { 218 Phdr *phdr = &(sgp->sg_phdr); 219 Os_desc *osp; 220 Aliste idx2; 221 222 /* 223 * If we've already processed a loadable segment, the `scn' 224 * variable will be initialized to the last section that was 225 * part of that segment. Add sufficient padding to this section 226 * to cause the next segments virtual address and file offset to 227 * be the same. 228 */ 229 if (oscn && (phdr->p_type == PT_LOAD)) { 230 Elf_Data * data; 231 size_t size; 232 233 size = (size_t)(S_ROUND(offset, phdr->p_align) - 234 offset); 235 236 if ((data = elf_newdata(oscn)) == NULL) { 237 ld_eprintf(ofl, ERR_ELF, 238 MSG_INTL(MSG_ELF_NEWDATA), ofl->ofl_name); 239 return (S_ERROR); 240 } 241 if ((data->d_buf = libld_calloc(size, 1)) == 0) 242 return (S_ERROR); 243 244 data->d_type = ELF_T_BYTE; 245 data->d_size = size; 246 data->d_align = 1; 247 data->d_version = ofl->ofl_dehdr->e_version; 248 } 249 250 /* 251 * Traverse the output sections for this segment calculating the 252 * offset of each section. Retain the final section descriptor 253 * as this will be where any padding buffer will be added. 254 */ 255 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) { 256 Shdr *shdr = osp->os_shdr; 257 258 offset = (off_t)S_ROUND(offset, shdr->sh_addralign); 259 offset += shdr->sh_size; 260 261 /* 262 * If this is a NOBITS output section convert all of 263 * its associated input sections into real, null filled, 264 * data buffers, and change the section to PROGBITS. 265 */ 266 if (shdr->sh_type == SHT_NOBITS) 267 shdr->sh_type = SHT_PROGBITS; 268 } 269 270 /* 271 * If this is a loadable segment retain the last output section 272 * descriptor. This acts both as a flag that a loadable 273 * segment has been seen, and as the segment to which a padding 274 * buffer will be added. 275 */ 276 if (phdr->p_type == PT_LOAD) 277 oscn = osp->os_scn; 278 } 279 return (1); 280 } 281 282 /* 283 * Create an output section. The first instance of an input section triggers 284 * the creation of a new output section. 285 */ 286 static uintptr_t 287 create_outsec(Ofl_desc *ofl, Sg_desc *sgp, Os_desc *osp, Word ptype, int shidx, 288 Boolean fixalign) 289 { 290 Elf_Scn *scn; 291 Shdr *shdr; 292 293 /* 294 * Get a section descriptor for the section. 295 */ 296 if ((scn = elf_newscn(ofl->ofl_welf)) == NULL) { 297 ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_NEWSCN), 298 ofl->ofl_name); 299 return (S_ERROR); 300 } 301 osp->os_scn = scn; 302 303 /* 304 * Get a new section header table entry and copy the pertinent 305 * information from the in-core descriptor. 306 */ 307 if ((shdr = elf_getshdr(scn)) == NULL) { 308 ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_GETSHDR), 309 ofl->ofl_name); 310 return (S_ERROR); 311 } 312 *shdr = *(osp->os_shdr); 313 osp->os_shdr = shdr; 314 315 /* 316 * If this is the first section within a loadable segment, and the 317 * alignment needs to be updated, record this section. 318 */ 319 if ((fixalign == TRUE) && (ptype == PT_LOAD) && (shidx == 1)) 320 sgp->sg_fscn = scn; 321 322 /* 323 * If not building a relocatable object, remove any of the 324 * following flags, as they have been acted upon and are not 325 * meaningful in the output: 326 * SHF_ORDERED, SHF_LINK_ORDER, SHF_GROUP 327 * For relocatable objects, we allow them to propagate to 328 * the output object to be handled by the next linker that 329 * sees them. 330 */ 331 if ((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) 332 osp->os_shdr->sh_flags &= ~(ALL_SHF_ORDER|SHF_GROUP); 333 334 /* 335 * If this is a TLS section, save it so that the PT_TLS program header 336 * information can be established after the output image has been 337 * initially created. At this point, all TLS input sections are ordered 338 * as they will appear in the output image. 339 */ 340 if ((ofl->ofl_flags & FLG_OF_TLSPHDR) && 341 (osp->os_shdr->sh_flags & SHF_TLS) && 342 (aplist_append(&ofl->ofl_ostlsseg, osp, 343 AL_CNT_OFL_OSTLSSEG) == NULL)) 344 return (S_ERROR); 345 346 return (0); 347 } 348 349 /* 350 * Create the elf structures that allow the input data to be associated with the 351 * new image: 352 * 353 * - define the new elf image using elf_begin(), 354 * 355 * - obtain an elf header for the image, 356 * 357 * - traverse the input segments and create a program header array to define 358 * the required segments, 359 * 360 * - traverse the output sections for each segment assigning a new section 361 * descriptor and section header for each, 362 * 363 * - traverse the input sections associated with each output section and 364 * assign a new data descriptor to each (each output section becomes a 365 * linked list of input data buffers). 366 */ 367 uintptr_t 368 ld_create_outfile(Ofl_desc *ofl) 369 { 370 Sg_desc *sgp; 371 Os_desc *osp; 372 Is_desc *isp; 373 Elf_Data *tlsdata = 0; 374 Aliste idx1; 375 ofl_flag_t flags = ofl->ofl_flags; 376 ofl_flag_t flags1 = ofl->ofl_flags1; 377 size_t ndx; 378 Elf_Cmd cmd; 379 Boolean fixalign = FALSE; 380 int fd, nseg = 0, shidx, dataidx, ptloadidx = 0; 381 382 DBG_CALL(Dbg_basic_create(ofl->ofl_lml)); 383 384 /* 385 * If DF_1_NOHDR or FLG_OF1_VADDR were set, 386 * we need to do alignment adjustment. 387 */ 388 if ((flags1 & FLG_OF1_VADDR) || 389 (ofl->ofl_dtflags_1 & DF_1_NOHDR)) { 390 fixalign = TRUE; 391 } 392 393 if (flags1 & FLG_OF1_MEMORY) { 394 cmd = ELF_C_IMAGE; 395 fd = 0; 396 } else { 397 fd = ofl->ofl_fd; 398 cmd = ELF_C_WRITE; 399 } 400 401 /* 402 * If there are any ordered sections, handle them here. 403 */ 404 if ((ofl->ofl_ordered != NULL) && 405 (ld_sort_ordered(ofl) == S_ERROR)) 406 return (S_ERROR); 407 408 /* 409 * Tell the access library about our new temporary file. 410 */ 411 if ((ofl->ofl_welf = elf_begin(fd, cmd, 0)) == NULL) { 412 ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_BEGIN), 413 ofl->ofl_name); 414 return (S_ERROR); 415 } 416 417 /* 418 * Obtain a new Elf header. 419 */ 420 if ((ofl->ofl_nehdr = elf_newehdr(ofl->ofl_welf)) == NULL) { 421 ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_NEWEHDR), 422 ofl->ofl_name); 423 return (S_ERROR); 424 } 425 ofl->ofl_nehdr->e_machine = ofl->ofl_dehdr->e_machine; 426 427 DBG_CALL(Dbg_util_nl(ofl->ofl_lml, DBG_NL_STD)); 428 for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) { 429 int frst = 0; 430 Phdr *phdr = &(sgp->sg_phdr); 431 Word ptype = phdr->p_type; 432 Aliste idx2; 433 Os_desc *nonempty = NULL; /* First non-empty section */ 434 435 /* 436 * Count the number of segments that will go in the program 437 * header table. If a segment is empty, ignore it. 438 */ 439 if (!(flags & FLG_OF_RELOBJ)) { 440 /* 441 * If the program header type belongs to the os range, 442 * the resulting object is ELFOSABI_SOLARIS. 443 */ 444 if ((ptype >= PT_LOOS) && (ptype <= PT_HIOS)) 445 ofl->ofl_flags |= FLG_OF_OSABI; 446 447 if (ptype == PT_PHDR) { 448 /* 449 * If we are generating an interp section (and 450 * thus an associated PT_INTERP program header 451 * entry) also generate a PT_PHDR program header 452 * entry. This allows the kernel to generate 453 * the appropriate aux vector entries to pass to 454 * the interpreter (refer to exec/elf/elf.c). 455 * Note that if an image was generated with an 456 * interp section, but no associated PT_PHDR 457 * program header entry, the kernel will simply 458 * pass the interpreter an open file descriptor 459 * when the image is executed). 460 */ 461 if (ofl->ofl_osinterp) 462 nseg++; 463 } else if (ptype == PT_INTERP) { 464 if (ofl->ofl_osinterp) 465 nseg++; 466 } else if (ptype == PT_DYNAMIC) { 467 if (flags & FLG_OF_DYNAMIC) 468 nseg++; 469 } else if (ptype == PT_TLS) { 470 if (flags & FLG_OF_TLSPHDR) 471 nseg++; 472 } else if (ptype == PT_SUNW_UNWIND) { 473 if (ofl->ofl_unwindhdr) 474 nseg++; 475 } else if (ptype == PT_SUNWDTRACE) { 476 if (ofl->ofl_dtracesym) 477 nseg++; 478 } else if (ptype == PT_SUNWCAP) { 479 if (ofl->ofl_oscap) 480 nseg++; 481 } else if (ptype == PT_SUNWSTACK) { 482 if ((sgp->sg_flags & FLG_SG_DISABLED) == 0) 483 nseg++; 484 } else if (sgp->sg_flags & FLG_SG_EMPTY) { 485 nseg++; 486 } else if (aplist_nitems(sgp->sg_osdescs) != 0) { 487 if ((sgp->sg_flags & FLG_SG_PHREQ) == 0) { 488 /* 489 * If this is a segment for which 490 * we are not making a program header, 491 * don't increment nseg 492 */ 493 ptype = (sgp->sg_phdr).p_type = PT_NULL; 494 } else if (ptype != PT_NULL) 495 nseg++; 496 } 497 } 498 499 /* 500 * Establish any processing unique to the first loadable 501 * segment. 502 */ 503 if ((ptype == PT_LOAD) && (ptloadidx == 0)) { 504 ptloadidx++; 505 506 /* 507 * If the first loadable segment is not supposed to 508 * include the ELF or program headers, alignments 509 * of the following segments need to be fixed, 510 * plus a .dynamic FLAGS1 setting is required. 511 */ 512 if (ofl->ofl_dtflags_1 & DF_1_NOHDR) 513 fixalign = TRUE; 514 } 515 516 shidx = 0; 517 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) { 518 Aliste idx3; 519 int os_isdescs_idx; 520 521 dataidx = 0; 522 523 OS_ISDESCS_TRAVERSE(os_isdescs_idx, osp, idx3, isp) { 524 Elf_Data *data; 525 Ifl_desc *ifl = isp->is_file; 526 527 /* 528 * An input section in the list that has 529 * been previously marked to be discarded 530 * should be completely ignored. 531 */ 532 if (isp->is_flags & FLG_IS_DISCARD) 533 continue; 534 535 /* 536 * At this point we know whether a section has 537 * been referenced. If it hasn't, and the whole 538 * file hasn't been referenced (which would have 539 * been caught in ignore_section_processing()), 540 * give a diagnostic (-D unused,detail) or 541 * discard the section if -zignore is in effect. 542 */ 543 if (ifl && 544 (((ifl->ifl_flags & FLG_IF_FILEREF) == 0) || 545 ((ptype == PT_LOAD) && 546 ((isp->is_flags & FLG_IS_SECTREF) == 0) && 547 (isp->is_shdr->sh_size > 0)))) { 548 Lm_list *lml = ofl->ofl_lml; 549 550 if (ifl->ifl_flags & FLG_IF_IGNORE) { 551 isp->is_flags |= FLG_IS_DISCARD; 552 DBG_CALL(Dbg_unused_sec(lml, 553 isp)); 554 continue; 555 } else { 556 DBG_CALL(Dbg_unused_sec(lml, 557 isp)); 558 } 559 } 560 561 /* 562 * If this section provides no data, and isn't 563 * referenced, then it can be discarded as well. 564 * Note, if this is the first input section 565 * associated to an output section, let it 566 * through, there may be a legitimate reason why 567 * the user wants a null section. Discarding 568 * additional sections is intended to remove the 569 * empty clutter the compilers have a habit of 570 * creating. Don't provide an unused diagnostic 571 * as these sections aren't typically the users 572 * creation. 573 */ 574 if (ifl && dataidx && 575 ((isp->is_flags & FLG_IS_SECTREF) == 0) && 576 (isp->is_shdr->sh_size == 0)) { 577 isp->is_flags |= FLG_IS_DISCARD; 578 continue; 579 } 580 581 /* 582 * The first input section triggers the creation 583 * of the associated output section. 584 */ 585 if (osp->os_scn == NULL) { 586 shidx++; 587 588 if (create_outsec(ofl, sgp, osp, ptype, 589 shidx, fixalign) == S_ERROR) 590 return (S_ERROR); 591 } 592 593 dataidx++; 594 595 /* 596 * Create a new output data buffer for each 597 * input data buffer, thus linking the new 598 * buffers to the new elf output structures. 599 * Simply make the new data buffers point to 600 * the old data. 601 */ 602 if ((data = elf_newdata(osp->os_scn)) == NULL) { 603 ld_eprintf(ofl, ERR_ELF, 604 MSG_INTL(MSG_ELF_NEWDATA), 605 ofl->ofl_name); 606 return (S_ERROR); 607 } 608 *data = *(isp->is_indata); 609 isp->is_indata = data; 610 611 if ((fixalign == TRUE) && (ptype == PT_LOAD) && 612 (shidx == 1) && (dataidx == 1)) 613 data->d_align = sgp->sg_align; 614 615 /* 616 * Save the first TLS data buffer, as this is 617 * the start of the TLS segment. Realign this 618 * buffer based on the alignment requirements 619 * of all the TLS input sections. 620 */ 621 if ((flags & FLG_OF_TLSPHDR) && 622 (isp->is_shdr->sh_flags & SHF_TLS)) { 623 if (tlsdata == 0) 624 tlsdata = data; 625 tlsdata->d_align = 626 ld_lcm(tlsdata->d_align, 627 isp->is_shdr->sh_addralign); 628 } 629 630 #if defined(_ELF64) && defined(_ILP32) 631 /* 632 * 4106312, the 32-bit ELF64 version of ld 633 * needs to be able to create large .bss 634 * sections. The d_size member of Elf_Data 635 * only allows 32-bits in _ILP32, so we build 636 * multiple data-items that each fit into 32- 637 * bits. libelf (4106398) can summ these up 638 * into a 64-bit quantity. This only works 639 * for NOBITS sections which don't have any 640 * real data to maintain and don't require 641 * large file support. 642 */ 643 if (isp->is_shdr->sh_type == SHT_NOBITS) { 644 Xword sz = isp->is_shdr->sh_size; 645 646 while (sz >> 32) { 647 data->d_size = SIZE_MAX; 648 sz -= (Xword)SIZE_MAX; 649 650 data = elf_newdata(osp->os_scn); 651 if (data == NULL) 652 return (S_ERROR); 653 } 654 data->d_size = (size_t)sz; 655 } 656 #endif 657 658 /* 659 * If this segment requires rounding realign the 660 * first data buffer associated with the first 661 * section. 662 */ 663 if ((frst++ == 0) && 664 (sgp->sg_flags & FLG_SG_ROUND)) { 665 Xword align; 666 667 if (data->d_align) 668 align = (Xword) 669 S_ROUND(data->d_align, 670 sgp->sg_round); 671 else 672 align = sgp->sg_round; 673 674 data->d_align = (size_t)align; 675 } 676 677 if ((data->d_size != 0) && (nonempty == NULL)) { 678 nonempty = osp; 679 } 680 } 681 682 /* 683 * Clear the szoutrels counter so that it can be used 684 * again in the building of relocs. See machrel.c. 685 */ 686 osp->os_szoutrels = 0; 687 } 688 689 /* 690 * We need to raise the alignment of any empty sections at the 691 * start of a segment to be at least as aligned as the first 692 * non-empty section, such that the empty and first non-empty 693 * sections are placed at the same offset. 694 */ 695 if (nonempty != NULL) { 696 Elf_Data *ne = NULL; 697 Xword pad_align = 1; 698 699 ne = elf_getdata(nonempty->os_scn, NULL); 700 assert(ne != NULL); 701 702 do { 703 pad_align = ld_lcm(pad_align, ne->d_align); 704 ne = elf_getdata(nonempty->os_scn, ne); 705 } while (ne != NULL); 706 707 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) { 708 Elf_Data *d = NULL; 709 710 /* Stop at the first non-empty section */ 711 if (osp == nonempty) 712 break; 713 714 d = elf_getdata(osp->os_scn, NULL); 715 716 if (d != NULL) 717 d->d_align = pad_align; 718 } 719 } 720 } 721 722 /* 723 * Did we use ELF features from the osabi range? If so, 724 * update the ELF header osabi fields. If this doesn't happen, 725 * those fields remain 0, reflecting a generic System V ELF ABI. 726 */ 727 if (ofl->ofl_flags & FLG_OF_OSABI) { 728 ofl->ofl_nehdr->e_ident[EI_OSABI] = ELFOSABI_SOLARIS; 729 ofl->ofl_nehdr->e_ident[EI_ABIVERSION] = EAV_SUNW_CURRENT; 730 } 731 732 /* 733 * Build an empty PHDR. 734 */ 735 if (nseg) { 736 if ((ofl->ofl_phdr = elf_newphdr(ofl->ofl_welf, 737 nseg)) == NULL) { 738 ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_NEWPHDR), 739 ofl->ofl_name); 740 return (S_ERROR); 741 } 742 } 743 744 /* 745 * If we need to generate a memory model, pad the image. 746 */ 747 if (flags1 & FLG_OF1_MEMORY) { 748 if (pad_outfile(ofl) == S_ERROR) 749 return (S_ERROR); 750 } 751 752 /* 753 * After all the basic input file processing, all data pointers are 754 * referencing two types of memory: 755 * 756 * - allocated memory, ie. elf structures, internal link editor 757 * structures, and any new sections that have been created. 758 * 759 * - original input file mmap'ed memory, ie. the actual data 760 * sections of the input file images. 761 * 762 * Up until now, the only memory modifications have been carried out on 763 * the allocated memory. Before carrying out any relocations, write the 764 * new output file image and reassign any necessary data pointers to the 765 * output files memory image. This insures that any relocation 766 * modifications are made to the output file image and not to the input 767 * file image, thus preventing the creation of dirty pages and reducing 768 * the overall swap space requirement. 769 * 770 * Write out the elf structure so as to create the new file image. 771 */ 772 if ((ofl->ofl_size = (size_t)elf_update(ofl->ofl_welf, 773 ELF_C_WRIMAGE)) == (size_t)-1) { 774 ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_UPDATE), 775 ofl->ofl_name); 776 return (S_ERROR); 777 } 778 779 /* 780 * Initialize the true `ofl' information with the memory images address 781 * and size. This will be used to write() out the image once any 782 * relocation processing has been completed. We also use this image 783 * information to setup a new Elf descriptor, which is used to obtain 784 * all the necessary elf pointers within the new output image. 785 */ 786 if ((ofl->ofl_elf = elf_begin(0, ELF_C_IMAGE, 787 ofl->ofl_welf)) == NULL) { 788 ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_BEGIN), 789 ofl->ofl_name); 790 return (S_ERROR); 791 } 792 if ((ofl->ofl_nehdr = elf_getehdr(ofl->ofl_elf)) == NULL) { 793 ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_GETEHDR), 794 ofl->ofl_name); 795 return (S_ERROR); 796 } 797 if (!(flags & FLG_OF_RELOBJ)) 798 if ((ofl->ofl_phdr = elf_getphdr(ofl->ofl_elf)) == NULL) { 799 ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_GETPHDR), 800 ofl->ofl_name); 801 return (S_ERROR); 802 } 803 804 /* 805 * Reinitialize the section descriptors, section headers and obtain new 806 * output data buffer pointers (these will be used to perform any 807 * relocations). 808 */ 809 ndx = 0; 810 for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) { 811 Phdr *_phdr = &(sgp->sg_phdr); 812 Os_desc *osp; 813 Aliste idx2; 814 Boolean recorded = FALSE; 815 816 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) { 817 /* 818 * Make sure that an output section was originally 819 * created. Input sections that had been marked as 820 * discarded may have made an output section 821 * unnecessary. Remove this alist entry so that 822 * future output section descriptor processing doesn't 823 * have to compensate for this empty section. 824 */ 825 if (osp->os_scn == NULL) { 826 aplist_delete(sgp->sg_osdescs, &idx2); 827 continue; 828 } 829 if ((osp->os_scn = 830 elf_getscn(ofl->ofl_elf, ++ndx)) == NULL) { 831 ld_eprintf(ofl, ERR_ELF, 832 MSG_INTL(MSG_ELF_GETSCN), ofl->ofl_name, 833 ndx); 834 return (S_ERROR); 835 } 836 if ((osp->os_shdr = 837 elf_getshdr(osp->os_scn)) == NULL) { 838 ld_eprintf(ofl, ERR_ELF, 839 MSG_INTL(MSG_ELF_GETSHDR), ofl->ofl_name); 840 return (S_ERROR); 841 } 842 if ((fixalign == TRUE) && sgp->sg_fscn && 843 (recorded == FALSE)) { 844 size_t fndx; 845 Elf_Scn *scn; 846 847 scn = sgp->sg_fscn; 848 if ((fndx = elf_ndxscn(scn)) == SHN_UNDEF) { 849 ld_eprintf(ofl, ERR_ELF, 850 MSG_INTL(MSG_ELF_NDXSCN), 851 ofl->ofl_name); 852 return (S_ERROR); 853 } 854 if (ndx == fndx) { 855 sgp->sg_fscn = osp->os_scn; 856 recorded = TRUE; 857 } 858 } 859 860 if ((osp->os_outdata = 861 elf_getdata(osp->os_scn, NULL)) == NULL) { 862 ld_eprintf(ofl, ERR_ELF, 863 MSG_INTL(MSG_ELF_GETDATA), ofl->ofl_name); 864 return (S_ERROR); 865 } 866 867 /* 868 * If this section is part of a loadable segment insure 869 * that the segments alignment is appropriate. 870 */ 871 if (_phdr->p_type == PT_LOAD) { 872 _phdr->p_align = ld_lcm(_phdr->p_align, 873 osp->os_shdr->sh_addralign); 874 } 875 } 876 } 877 return (1); 878 } 879