Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 1 | /* Find debugging and symbol information for a module in libdwfl. |
| 2 | Copyright (C) 2005-2011 Red Hat, Inc. |
| 3 | This file is part of Red Hat elfutils. |
| 4 | |
| 5 | Red Hat elfutils is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by the |
| 7 | Free Software Foundation; version 2 of the License. |
| 8 | |
| 9 | Red Hat elfutils is distributed in the hope that it will be useful, but |
| 10 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | General Public License for more details. |
| 13 | |
| 14 | You should have received a copy of the GNU General Public License along |
| 15 | with Red Hat elfutils; if not, write to the Free Software Foundation, |
| 16 | Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. |
| 17 | |
| 18 | In addition, as a special exception, Red Hat, Inc. gives You the |
| 19 | additional right to link the code of Red Hat elfutils with code licensed |
| 20 | under any Open Source Initiative certified open source license |
| 21 | (http://www.opensource.org/licenses/index.php) which requires the |
| 22 | distribution of source code with any binary distribution and to |
| 23 | distribute linked combinations of the two. Non-GPL Code permitted under |
| 24 | this exception must only link to the code of Red Hat elfutils through |
| 25 | those well defined interfaces identified in the file named EXCEPTION |
| 26 | found in the source code files (the "Approved Interfaces"). The files |
| 27 | of Non-GPL Code may instantiate templates or use macros or inline |
| 28 | functions from the Approved Interfaces without causing the resulting |
| 29 | work to be covered by the GNU General Public License. Only Red Hat, |
| 30 | Inc. may make changes or additions to the list of Approved Interfaces. |
| 31 | Red Hat's grant of this exception is conditioned upon your not adding |
| 32 | any new exceptions. If you wish to add a new Approved Interface or |
| 33 | exception, please contact Red Hat. You must obey the GNU General Public |
| 34 | License in all respects for all of the Red Hat elfutils code and other |
| 35 | code used in conjunction with Red Hat elfutils except the Non-GPL Code |
| 36 | covered by this exception. If you modify this file, you may extend this |
| 37 | exception to your version of the file, but you are not obligated to do |
| 38 | so. If you do not wish to provide this exception without modification, |
| 39 | you must delete this exception statement from your version and license |
| 40 | this file solely under the GPL without exception. |
| 41 | |
| 42 | Red Hat elfutils is an included package of the Open Invention Network. |
| 43 | An included package of the Open Invention Network is a package for which |
| 44 | Open Invention Network licensees cross-license their patents. No patent |
| 45 | license is granted, either expressly or impliedly, by designation as an |
| 46 | included package. Should you wish to participate in the Open Invention |
| 47 | Network licensing program, please visit www.openinventionnetwork.com |
| 48 | <http://www.openinventionnetwork.com>. */ |
| 49 | |
| 50 | #include "libdwflP.h" |
| 51 | #include <fcntl.h> |
| 52 | #include <string.h> |
| 53 | #include <unistd.h> |
| 54 | #include "../libdw/libdwP.h" /* DWARF_E_* values are here. */ |
| 55 | |
| 56 | |
| 57 | /* Open libelf FILE->fd and compute the load base of ELF as loaded in MOD. |
| 58 | When we return success, FILE->elf and FILE->vaddr are set up. */ |
| 59 | static inline Dwfl_Error |
| 60 | open_elf (Dwfl_Module *mod, struct dwfl_file *file) |
| 61 | { |
| 62 | if (file->elf == NULL) |
| 63 | { |
| 64 | /* CBFAIL uses errno if it's set, so clear it first in case we don't |
| 65 | set it with an open failure below. */ |
| 66 | errno = 0; |
| 67 | |
| 68 | /* If there was a pre-primed file name left that the callback left |
| 69 | behind, try to open that file name. */ |
| 70 | if (file->fd < 0 && file->name != NULL) |
| 71 | file->fd = TEMP_FAILURE_RETRY (open64 (file->name, O_RDONLY)); |
| 72 | |
| 73 | if (file->fd < 0) |
| 74 | return CBFAIL; |
| 75 | |
| 76 | Dwfl_Error error = __libdw_open_file (&file->fd, &file->elf, true, false); |
| 77 | if (error != DWFL_E_NOERROR) |
| 78 | return error; |
| 79 | } |
| 80 | else if (unlikely (elf_kind (file->elf) != ELF_K_ELF)) |
| 81 | { |
| 82 | elf_end (file->elf); |
| 83 | file->elf = NULL; |
| 84 | close (file->fd); |
| 85 | file->fd = -1; |
| 86 | return DWFL_E_BADELF; |
| 87 | } |
| 88 | |
| 89 | GElf_Ehdr ehdr_mem, *ehdr = gelf_getehdr (file->elf, &ehdr_mem); |
| 90 | if (ehdr == NULL) |
| 91 | { |
| 92 | elf_error: |
| 93 | elf_end (file->elf); |
| 94 | file->elf = NULL; |
| 95 | close (file->fd); |
| 96 | file->fd = -1; |
| 97 | return DWFL_E (LIBELF, elf_errno ()); |
| 98 | } |
| 99 | |
| 100 | if (mod->e_type != ET_REL) |
| 101 | { |
| 102 | /* In any non-ET_REL file, we compute the "synchronization address". |
| 103 | |
| 104 | We start with the address at the end of the first PT_LOAD |
| 105 | segment. When prelink converts REL to RELA in an ET_DYN |
| 106 | file, it expands the space between the beginning of the |
| 107 | segment and the actual code/data addresses. Since that |
| 108 | change wasn't made in the debug file, the distance from |
| 109 | p_vaddr to an address of interest (in an st_value or DWARF |
| 110 | data) now differs between the main and debug files. The |
| 111 | distance from address_sync to an address of interest remains |
| 112 | consistent. |
| 113 | |
| 114 | If there are no section headers at all (full stripping), then |
| 115 | the end of the first segment is a valid synchronization address. |
| 116 | This cannot happen in a prelinked file, since prelink itself |
| 117 | relies on section headers for prelinking and for undoing it. |
| 118 | (If you do full stripping on a prelinked file, then you get what |
| 119 | you deserve--you can neither undo the prelinking, nor expect to |
| 120 | line it up with a debug file separated before prelinking.) |
| 121 | |
| 122 | However, when prelink processes an ET_EXEC file, it can do |
| 123 | something different. There it juggles the "special" sections |
| 124 | (SHT_DYNSYM et al) to make space for the additional prelink |
| 125 | special sections. Sometimes it will do this by moving a special |
| 126 | section like .dynstr after the real program sections in the first |
| 127 | PT_LOAD segment--i.e. to the end. That changes the end address of |
| 128 | the segment, so it no longer lines up correctly and is not a valid |
| 129 | synchronization address to use. Because of this, we need to apply |
| 130 | a different prelink-savvy means to discover the synchronization |
| 131 | address when there is a separate debug file and a prelinked main |
| 132 | file. That is done in find_debuginfo, below. */ |
| 133 | |
| 134 | size_t phnum; |
| 135 | if (unlikely (elf_getphdrnum (file->elf, &phnum) != 0)) |
| 136 | goto elf_error; |
| 137 | |
| 138 | file->vaddr = file->address_sync = 0; |
| 139 | for (size_t i = 0; i < phnum; ++i) |
| 140 | { |
| 141 | GElf_Phdr ph_mem; |
| 142 | GElf_Phdr *ph = gelf_getphdr (file->elf, i, &ph_mem); |
| 143 | if (unlikely (ph == NULL)) |
| 144 | goto elf_error; |
| 145 | if (ph->p_type == PT_LOAD) |
| 146 | { |
| 147 | file->vaddr = ph->p_vaddr & -ph->p_align; |
| 148 | file->address_sync = ph->p_vaddr + ph->p_memsz; |
| 149 | break; |
| 150 | } |
| 151 | } |
| 152 | } |
| 153 | |
| 154 | mod->e_type = ehdr->e_type; |
| 155 | |
| 156 | /* Relocatable Linux kernels are ET_EXEC but act like ET_DYN. */ |
| 157 | if (mod->e_type == ET_EXEC && file->vaddr != mod->low_addr) |
| 158 | mod->e_type = ET_DYN; |
| 159 | |
| 160 | return DWFL_E_NOERROR; |
| 161 | } |
| 162 | |
| 163 | /* Find the main ELF file for this module and open libelf on it. |
| 164 | When we return success, MOD->main.elf and MOD->main.bias are set up. */ |
| 165 | void |
| 166 | internal_function |
| 167 | __libdwfl_getelf (Dwfl_Module *mod) |
| 168 | { |
| 169 | if (mod->main.elf != NULL /* Already done. */ |
| 170 | || mod->elferr != DWFL_E_NOERROR) /* Cached failure. */ |
| 171 | return; |
| 172 | |
| 173 | mod->main.fd = (*mod->dwfl->callbacks->find_elf) (MODCB_ARGS (mod), |
| 174 | &mod->main.name, |
| 175 | &mod->main.elf); |
| 176 | const bool fallback = mod->main.elf == NULL && mod->main.fd < 0; |
| 177 | mod->elferr = open_elf (mod, &mod->main); |
| 178 | if (mod->elferr != DWFL_E_NOERROR) |
| 179 | return; |
| 180 | |
| 181 | if (!mod->main.valid) |
| 182 | { |
| 183 | /* Clear any explicitly reported build ID, just in case it was wrong. |
| 184 | We'll fetch it from the file when asked. */ |
| 185 | free (mod->build_id_bits); |
| 186 | mod->build_id_bits = NULL; |
| 187 | mod->build_id_len = 0; |
| 188 | } |
| 189 | else if (fallback) |
| 190 | { |
| 191 | /* We have an authoritative build ID for this module, so |
| 192 | don't use a file by name that doesn't match that ID. */ |
| 193 | |
| 194 | assert (mod->build_id_len > 0); |
| 195 | |
| 196 | switch (__builtin_expect (__libdwfl_find_build_id (mod, false, |
| 197 | mod->main.elf), 2)) |
| 198 | { |
| 199 | case 2: |
| 200 | /* Build ID matches as it should. */ |
| 201 | return; |
| 202 | |
| 203 | case -1: /* ELF error. */ |
| 204 | mod->elferr = INTUSE(dwfl_errno) (); |
| 205 | break; |
| 206 | |
| 207 | case 0: /* File has no build ID note. */ |
| 208 | case 1: /* FIle has a build ID that does not match. */ |
| 209 | mod->elferr = DWFL_E_WRONG_ID_ELF; |
| 210 | break; |
| 211 | |
| 212 | default: |
| 213 | abort (); |
| 214 | } |
| 215 | |
| 216 | /* We get here when it was the right ELF file. Clear it out. */ |
| 217 | elf_end (mod->main.elf); |
| 218 | mod->main.elf = NULL; |
| 219 | if (mod->main.fd >= 0) |
| 220 | { |
| 221 | close (mod->main.fd); |
| 222 | mod->main.fd = -1; |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | mod->main_bias = mod->e_type == ET_REL ? 0 : mod->low_addr - mod->main.vaddr; |
| 227 | } |
| 228 | |
| 229 | /* Search an ELF file for a ".gnu_debuglink" section. */ |
| 230 | static const char * |
| 231 | find_debuglink (Elf *elf, GElf_Word *crc) |
| 232 | { |
| 233 | size_t shstrndx; |
| 234 | if (elf_getshdrstrndx (elf, &shstrndx) < 0) |
| 235 | return NULL; |
| 236 | |
| 237 | Elf_Scn *scn = NULL; |
| 238 | while ((scn = elf_nextscn (elf, scn)) != NULL) |
| 239 | { |
| 240 | GElf_Shdr shdr_mem; |
| 241 | GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem); |
| 242 | if (shdr == NULL) |
| 243 | return NULL; |
| 244 | |
| 245 | const char *name = elf_strptr (elf, shstrndx, shdr->sh_name); |
| 246 | if (name == NULL) |
| 247 | return NULL; |
| 248 | |
| 249 | if (!strcmp (name, ".gnu_debuglink")) |
| 250 | break; |
| 251 | } |
| 252 | |
| 253 | if (scn == NULL) |
| 254 | return NULL; |
| 255 | |
| 256 | /* Found the .gnu_debuglink section. Extract its contents. */ |
| 257 | Elf_Data *rawdata = elf_rawdata (scn, NULL); |
| 258 | if (rawdata == NULL) |
| 259 | return NULL; |
| 260 | |
| 261 | Elf_Data crcdata = |
| 262 | { |
| 263 | .d_type = ELF_T_WORD, |
| 264 | .d_buf = crc, |
| 265 | .d_size = sizeof *crc, |
| 266 | .d_version = EV_CURRENT, |
| 267 | }; |
| 268 | Elf_Data conv = |
| 269 | { |
| 270 | .d_type = ELF_T_WORD, |
| 271 | .d_buf = rawdata->d_buf + rawdata->d_size - sizeof *crc, |
| 272 | .d_size = sizeof *crc, |
| 273 | .d_version = EV_CURRENT, |
| 274 | }; |
| 275 | |
| 276 | GElf_Ehdr ehdr_mem; |
| 277 | GElf_Ehdr *ehdr = gelf_getehdr (elf, &ehdr_mem); |
| 278 | if (ehdr == NULL) |
| 279 | return NULL; |
| 280 | |
| 281 | Elf_Data *d = gelf_xlatetom (elf, &crcdata, &conv, ehdr->e_ident[EI_DATA]); |
| 282 | if (d == NULL) |
| 283 | return NULL; |
| 284 | assert (d == &crcdata); |
| 285 | |
| 286 | return rawdata->d_buf; |
| 287 | } |
| 288 | |
| 289 | /* If the main file might have been prelinked, then we need to |
| 290 | discover the correct synchronization address between the main and |
| 291 | debug files. Because of prelink's section juggling, we cannot rely |
| 292 | on the address_sync computed from PT_LOAD segments (see open_elf). |
| 293 | |
| 294 | We will attempt to discover a synchronization address based on the |
| 295 | section headers instead. But finding a section address that is |
| 296 | safe to use requires identifying which sections are SHT_PROGBITS. |
| 297 | We can do that in the main file, but in the debug file all the |
| 298 | allocated sections have been transformed into SHT_NOBITS so we have |
| 299 | lost the means to match them up correctly. |
| 300 | |
| 301 | The only method left to us is to decode the .gnu.prelink_undo |
| 302 | section in the prelinked main file. This shows what the sections |
| 303 | looked like before prelink juggled them--when they still had a |
| 304 | direct correspondence to the debug file. */ |
| 305 | static Dwfl_Error |
| 306 | find_prelink_address_sync (Dwfl_Module *mod) |
| 307 | { |
| 308 | /* The magic section is only identified by name. */ |
| 309 | size_t shstrndx; |
| 310 | if (elf_getshdrstrndx (mod->main.elf, &shstrndx) < 0) |
| 311 | return DWFL_E_LIBELF; |
| 312 | |
| 313 | Elf_Scn *scn = NULL; |
| 314 | while ((scn = elf_nextscn (mod->main.elf, scn)) != NULL) |
| 315 | { |
| 316 | GElf_Shdr shdr_mem; |
| 317 | GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem); |
| 318 | if (unlikely (shdr == NULL)) |
| 319 | return DWFL_E_LIBELF; |
| 320 | if (shdr->sh_type == SHT_PROGBITS |
| 321 | && !(shdr->sh_flags & SHF_ALLOC) |
| 322 | && shdr->sh_name != 0) |
| 323 | { |
| 324 | const char *secname = elf_strptr (mod->main.elf, shstrndx, |
| 325 | shdr->sh_name); |
| 326 | if (unlikely (secname == NULL)) |
| 327 | return DWFL_E_LIBELF; |
| 328 | if (!strcmp (secname, ".gnu.prelink_undo")) |
| 329 | break; |
| 330 | } |
| 331 | } |
| 332 | |
| 333 | if (scn == NULL) |
| 334 | /* There was no .gnu.prelink_undo section. */ |
| 335 | return DWFL_E_NOERROR; |
| 336 | |
| 337 | Elf_Data *undodata = elf_rawdata (scn, NULL); |
| 338 | if (unlikely (undodata == NULL)) |
| 339 | return DWFL_E_LIBELF; |
| 340 | |
| 341 | /* Decode the section. It consists of the original ehdr, phdrs, |
| 342 | and shdrs (but omits section 0). */ |
| 343 | |
| 344 | union |
| 345 | { |
| 346 | Elf32_Ehdr e32; |
| 347 | Elf64_Ehdr e64; |
| 348 | } ehdr; |
| 349 | Elf_Data dst = |
| 350 | { |
| 351 | .d_buf = &ehdr, |
| 352 | .d_size = sizeof ehdr, |
| 353 | .d_type = ELF_T_EHDR, |
| 354 | .d_version = EV_CURRENT |
| 355 | }; |
| 356 | Elf_Data src = *undodata; |
| 357 | src.d_size = gelf_fsize (mod->main.elf, ELF_T_EHDR, 1, EV_CURRENT); |
| 358 | src.d_type = ELF_T_EHDR; |
| 359 | if (unlikely (gelf_xlatetom (mod->main.elf, &dst, &src, |
| 360 | elf_getident (mod->main.elf, NULL)[EI_DATA]) |
| 361 | == NULL)) |
| 362 | return DWFL_E_LIBELF; |
| 363 | |
| 364 | size_t shentsize = gelf_fsize (mod->main.elf, ELF_T_SHDR, 1, EV_CURRENT); |
| 365 | size_t phentsize = gelf_fsize (mod->main.elf, ELF_T_PHDR, 1, EV_CURRENT); |
| 366 | |
| 367 | uint_fast16_t phnum; |
| 368 | uint_fast16_t shnum; |
| 369 | if (ehdr.e32.e_ident[EI_CLASS] == ELFCLASS32) |
| 370 | { |
| 371 | if (ehdr.e32.e_shentsize != shentsize |
| 372 | || ehdr.e32.e_phentsize != phentsize) |
| 373 | return DWFL_E_BAD_PRELINK; |
| 374 | phnum = ehdr.e32.e_phnum; |
| 375 | shnum = ehdr.e32.e_shnum; |
| 376 | } |
| 377 | else |
| 378 | { |
| 379 | if (ehdr.e64.e_shentsize != shentsize |
| 380 | || ehdr.e64.e_phentsize != phentsize) |
| 381 | return DWFL_E_BAD_PRELINK; |
| 382 | phnum = ehdr.e64.e_phnum; |
| 383 | shnum = ehdr.e64.e_shnum; |
| 384 | } |
| 385 | |
| 386 | /* Since prelink does not store the zeroth section header in the undo |
| 387 | section, it cannot support SHN_XINDEX encoding. */ |
| 388 | if (unlikely (shnum >= SHN_LORESERVE) |
| 389 | || unlikely (undodata->d_size != (src.d_size |
| 390 | + phnum * phentsize |
| 391 | + (shnum - 1) * shentsize))) |
| 392 | return DWFL_E_BAD_PRELINK; |
| 393 | |
| 394 | /* We look at the allocated SHT_PROGBITS (or SHT_NOBITS) sections. (Most |
| 395 | every file will have some SHT_PROGBITS sections, but it's possible to |
| 396 | have one with nothing but .bss, i.e. SHT_NOBITS.) The special sections |
| 397 | that can be moved around have different sh_type values--except for |
| 398 | .interp, the section that became the PT_INTERP segment. So we exclude |
| 399 | the SHT_PROGBITS section whose address matches the PT_INTERP p_vaddr. |
| 400 | For this reason, we must examine the phdrs first to find PT_INTERP. */ |
| 401 | |
| 402 | GElf_Addr main_interp = 0; |
| 403 | { |
| 404 | size_t main_phnum; |
| 405 | if (unlikely (elf_getphdrnum (mod->main.elf, &main_phnum))) |
| 406 | return DWFL_E_LIBELF; |
| 407 | for (size_t i = 0; i < main_phnum; ++i) |
| 408 | { |
| 409 | GElf_Phdr phdr; |
| 410 | if (unlikely (gelf_getphdr (mod->main.elf, i, &phdr) == NULL)) |
| 411 | return DWFL_E_LIBELF; |
| 412 | if (phdr.p_type == PT_INTERP) |
| 413 | { |
| 414 | main_interp = phdr.p_vaddr; |
| 415 | break; |
| 416 | } |
| 417 | } |
| 418 | } |
| 419 | |
| 420 | src.d_buf += src.d_size; |
| 421 | src.d_type = ELF_T_PHDR; |
| 422 | src.d_size = phnum * phentsize; |
| 423 | |
| 424 | GElf_Addr undo_interp = 0; |
| 425 | { |
| 426 | union |
| 427 | { |
| 428 | Elf32_Phdr p32[phnum]; |
| 429 | Elf64_Phdr p64[phnum]; |
| 430 | } phdr; |
| 431 | dst.d_buf = &phdr; |
| 432 | dst.d_size = sizeof phdr; |
| 433 | if (unlikely (gelf_xlatetom (mod->main.elf, &dst, &src, |
| 434 | ehdr.e32.e_ident[EI_DATA]) == NULL)) |
| 435 | return DWFL_E_LIBELF; |
| 436 | if (ehdr.e32.e_ident[EI_CLASS] == ELFCLASS32) |
| 437 | { |
| 438 | for (uint_fast16_t i = 0; i < phnum; ++i) |
| 439 | if (phdr.p32[i].p_type == PT_INTERP) |
| 440 | { |
| 441 | undo_interp = phdr.p32[i].p_vaddr; |
| 442 | break; |
| 443 | } |
| 444 | } |
| 445 | else |
| 446 | { |
| 447 | for (uint_fast16_t i = 0; i < phnum; ++i) |
| 448 | if (phdr.p64[i].p_type == PT_INTERP) |
| 449 | { |
| 450 | undo_interp = phdr.p64[i].p_vaddr; |
| 451 | break; |
| 452 | } |
| 453 | } |
| 454 | } |
| 455 | |
| 456 | if (unlikely ((main_interp == 0) != (undo_interp == 0))) |
| 457 | return DWFL_E_BAD_PRELINK; |
| 458 | |
| 459 | src.d_buf += src.d_size; |
| 460 | src.d_type = ELF_T_SHDR; |
| 461 | src.d_size = gelf_fsize (mod->main.elf, ELF_T_SHDR, shnum - 1, EV_CURRENT); |
| 462 | |
| 463 | union |
| 464 | { |
| 465 | Elf32_Shdr s32[shnum - 1]; |
| 466 | Elf64_Shdr s64[shnum - 1]; |
| 467 | } shdr; |
| 468 | dst.d_buf = &shdr; |
| 469 | dst.d_size = sizeof shdr; |
| 470 | if (unlikely (gelf_xlatetom (mod->main.elf, &dst, &src, |
| 471 | ehdr.e32.e_ident[EI_DATA]) == NULL)) |
| 472 | return DWFL_E_LIBELF; |
| 473 | |
| 474 | /* Now we can look at the original section headers of the main file |
| 475 | before it was prelinked. First we'll apply our method to the main |
| 476 | file sections as they are after prelinking, to calculate the |
| 477 | synchronization address of the main file. Then we'll apply that |
| 478 | same method to the saved section headers, to calculate the matching |
| 479 | synchronization address of the debug file. |
| 480 | |
| 481 | The method is to consider SHF_ALLOC sections that are either |
| 482 | SHT_PROGBITS or SHT_NOBITS, excluding the section whose sh_addr |
| 483 | matches the PT_INTERP p_vaddr. The special sections that can be |
| 484 | moved by prelink have other types, except for .interp (which |
| 485 | becomes PT_INTERP). The "real" sections cannot move as such, but |
| 486 | .bss can be split into .dynbss and .bss, with the total memory |
| 487 | image remaining the same but being spread across the two sections. |
| 488 | So we consider the highest section end, which still matches up. */ |
| 489 | |
| 490 | GElf_Addr highest; |
| 491 | |
| 492 | inline void consider_shdr (GElf_Addr interp, |
| 493 | GElf_Word sh_type, |
| 494 | GElf_Xword sh_flags, |
| 495 | GElf_Addr sh_addr, |
| 496 | GElf_Xword sh_size) |
| 497 | { |
| 498 | if ((sh_flags & SHF_ALLOC) |
| 499 | && ((sh_type == SHT_PROGBITS && sh_addr != interp) |
| 500 | || sh_type == SHT_NOBITS)) |
| 501 | { |
| 502 | const GElf_Addr sh_end = sh_addr + sh_size; |
| 503 | if (sh_end > highest) |
| 504 | highest = sh_end; |
| 505 | } |
| 506 | } |
| 507 | |
| 508 | highest = 0; |
| 509 | scn = NULL; |
| 510 | while ((scn = elf_nextscn (mod->main.elf, scn)) != NULL) |
| 511 | { |
| 512 | GElf_Shdr sh_mem; |
| 513 | GElf_Shdr *sh = gelf_getshdr (scn, &sh_mem); |
| 514 | if (unlikely (sh == NULL)) |
| 515 | return DWFL_E_LIBELF; |
| 516 | consider_shdr (main_interp, sh->sh_type, sh->sh_flags, |
| 517 | sh->sh_addr, sh->sh_size); |
| 518 | } |
| 519 | if (highest > mod->main.vaddr) |
| 520 | { |
| 521 | mod->main.address_sync = highest; |
| 522 | |
| 523 | highest = 0; |
| 524 | if (ehdr.e32.e_ident[EI_CLASS] == ELFCLASS32) |
| 525 | for (size_t i = 0; i < shnum - 1; ++i) |
| 526 | consider_shdr (undo_interp, shdr.s32[i].sh_type, shdr.s32[i].sh_flags, |
| 527 | shdr.s32[i].sh_addr, shdr.s32[i].sh_size); |
| 528 | else |
| 529 | for (size_t i = 0; i < shnum - 1; ++i) |
| 530 | consider_shdr (undo_interp, shdr.s64[i].sh_type, shdr.s64[i].sh_flags, |
| 531 | shdr.s64[i].sh_addr, shdr.s64[i].sh_size); |
| 532 | |
| 533 | if (highest > mod->debug.vaddr) |
| 534 | mod->debug.address_sync = highest; |
| 535 | else |
| 536 | return DWFL_E_BAD_PRELINK; |
| 537 | } |
| 538 | |
| 539 | return DWFL_E_NOERROR; |
| 540 | } |
| 541 | |
| 542 | /* Find the separate debuginfo file for this module and open libelf on it. |
| 543 | When we return success, MOD->debug is set up. */ |
| 544 | static Dwfl_Error |
| 545 | find_debuginfo (Dwfl_Module *mod) |
| 546 | { |
| 547 | if (mod->debug.elf != NULL) |
| 548 | return DWFL_E_NOERROR; |
| 549 | |
| 550 | GElf_Word debuglink_crc = 0; |
| 551 | const char *debuglink_file = find_debuglink (mod->main.elf, &debuglink_crc); |
| 552 | |
| 553 | mod->debug.fd = (*mod->dwfl->callbacks->find_debuginfo) (MODCB_ARGS (mod), |
| 554 | mod->main.name, |
| 555 | debuglink_file, |
| 556 | debuglink_crc, |
| 557 | &mod->debug.name); |
| 558 | Dwfl_Error result = open_elf (mod, &mod->debug); |
| 559 | if (result == DWFL_E_NOERROR && mod->debug.address_sync != 0) |
| 560 | result = find_prelink_address_sync (mod); |
| 561 | return result; |
| 562 | } |
| 563 | |
| 564 | |
| 565 | /* Try to find a symbol table in FILE. |
| 566 | Returns DWFL_E_NOERROR if a proper one is found. |
| 567 | Returns DWFL_E_NO_SYMTAB if not, but still sets results for SHT_DYNSYM. */ |
| 568 | static Dwfl_Error |
| 569 | load_symtab (struct dwfl_file *file, struct dwfl_file **symfile, |
| 570 | Elf_Scn **symscn, Elf_Scn **xndxscn, |
| 571 | size_t *syments, int *first_global, GElf_Word *strshndx) |
| 572 | { |
| 573 | bool symtab = false; |
| 574 | Elf_Scn *scn = NULL; |
| 575 | while ((scn = elf_nextscn (file->elf, scn)) != NULL) |
| 576 | { |
| 577 | GElf_Shdr shdr_mem, *shdr = gelf_getshdr (scn, &shdr_mem); |
| 578 | if (shdr != NULL) |
| 579 | switch (shdr->sh_type) |
| 580 | { |
| 581 | case SHT_SYMTAB: |
| 582 | symtab = true; |
| 583 | *symscn = scn; |
| 584 | *symfile = file; |
| 585 | *strshndx = shdr->sh_link; |
| 586 | *syments = shdr->sh_size / shdr->sh_entsize; |
| 587 | *first_global = shdr->sh_info; |
| 588 | if (*xndxscn != NULL) |
| 589 | return DWFL_E_NOERROR; |
| 590 | break; |
| 591 | |
| 592 | case SHT_DYNSYM: |
| 593 | if (symtab) |
| 594 | break; |
| 595 | /* Use this if need be, but keep looking for SHT_SYMTAB. */ |
| 596 | *symscn = scn; |
| 597 | *symfile = file; |
| 598 | *strshndx = shdr->sh_link; |
| 599 | *syments = shdr->sh_size / shdr->sh_entsize; |
| 600 | break; |
| 601 | |
| 602 | case SHT_SYMTAB_SHNDX: |
| 603 | *xndxscn = scn; |
| 604 | if (symtab) |
| 605 | return DWFL_E_NOERROR; |
| 606 | break; |
| 607 | |
| 608 | default: |
| 609 | break; |
| 610 | } |
| 611 | } |
| 612 | |
| 613 | if (symtab) |
| 614 | /* We found one, though no SHT_SYMTAB_SHNDX to go with it. */ |
| 615 | return DWFL_E_NOERROR; |
| 616 | |
| 617 | /* We found no SHT_SYMTAB, so any SHT_SYMTAB_SHNDX was bogus. |
| 618 | We might have found an SHT_DYNSYM and set *SYMSCN et al though. */ |
| 619 | *xndxscn = NULL; |
| 620 | return DWFL_E_NO_SYMTAB; |
| 621 | } |
| 622 | |
| 623 | |
| 624 | /* Translate addresses into file offsets. |
| 625 | OFFS[*] start out zero and remain zero if unresolved. */ |
| 626 | static void |
| 627 | find_offsets (Elf *elf, size_t phnum, size_t n, |
| 628 | GElf_Addr addrs[n], GElf_Off offs[n]) |
| 629 | { |
| 630 | size_t unsolved = n; |
| 631 | for (size_t i = 0; i < phnum; ++i) |
| 632 | { |
| 633 | GElf_Phdr phdr_mem; |
| 634 | GElf_Phdr *phdr = gelf_getphdr (elf, i, &phdr_mem); |
| 635 | if (phdr != NULL && phdr->p_type == PT_LOAD && phdr->p_memsz > 0) |
| 636 | for (size_t j = 0; j < n; ++j) |
| 637 | if (offs[j] == 0 |
| 638 | && addrs[j] >= phdr->p_vaddr |
| 639 | && addrs[j] - phdr->p_vaddr < phdr->p_filesz) |
| 640 | { |
| 641 | offs[j] = addrs[j] - phdr->p_vaddr + phdr->p_offset; |
| 642 | if (--unsolved == 0) |
| 643 | break; |
| 644 | } |
| 645 | } |
| 646 | } |
| 647 | |
| 648 | /* Try to find a dynamic symbol table via phdrs. */ |
| 649 | static void |
| 650 | find_dynsym (Dwfl_Module *mod) |
| 651 | { |
| 652 | GElf_Ehdr ehdr_mem; |
| 653 | GElf_Ehdr *ehdr = gelf_getehdr (mod->main.elf, &ehdr_mem); |
| 654 | |
| 655 | size_t phnum; |
| 656 | if (unlikely (elf_getphdrnum (mod->main.elf, &phnum) != 0)) |
| 657 | return; |
| 658 | |
| 659 | for (size_t i = 0; i < phnum; ++i) |
| 660 | { |
| 661 | GElf_Phdr phdr_mem; |
| 662 | GElf_Phdr *phdr = gelf_getphdr (mod->main.elf, i, &phdr_mem); |
| 663 | if (phdr == NULL) |
| 664 | break; |
| 665 | |
| 666 | if (phdr->p_type == PT_DYNAMIC) |
| 667 | { |
| 668 | /* Examine the dynamic section for the pointers we need. */ |
| 669 | |
| 670 | Elf_Data *data = elf_getdata_rawchunk (mod->main.elf, |
| 671 | phdr->p_offset, phdr->p_filesz, |
| 672 | ELF_T_DYN); |
| 673 | if (data == NULL) |
| 674 | continue; |
| 675 | |
| 676 | enum |
| 677 | { |
| 678 | i_symtab, |
| 679 | i_strtab, |
| 680 | i_hash, |
| 681 | i_gnu_hash, |
| 682 | i_max |
| 683 | }; |
| 684 | GElf_Addr addrs[i_max] = { 0, }; |
| 685 | GElf_Xword strsz = 0; |
| 686 | size_t n = data->d_size / gelf_fsize (mod->main.elf, |
| 687 | ELF_T_DYN, 1, EV_CURRENT); |
| 688 | for (size_t j = 0; j < n; ++j) |
| 689 | { |
| 690 | GElf_Dyn dyn_mem; |
| 691 | GElf_Dyn *dyn = gelf_getdyn (data, j, &dyn_mem); |
| 692 | if (dyn != NULL) |
| 693 | switch (dyn->d_tag) |
| 694 | { |
| 695 | case DT_SYMTAB: |
| 696 | addrs[i_symtab] = dyn->d_un.d_ptr; |
| 697 | continue; |
| 698 | |
| 699 | case DT_HASH: |
| 700 | addrs[i_hash] = dyn->d_un.d_ptr; |
| 701 | continue; |
| 702 | |
| 703 | case DT_GNU_HASH: |
| 704 | addrs[i_gnu_hash] = dyn->d_un.d_ptr; |
| 705 | continue; |
| 706 | |
| 707 | case DT_STRTAB: |
| 708 | addrs[i_strtab] = dyn->d_un.d_ptr; |
| 709 | continue; |
| 710 | |
| 711 | case DT_STRSZ: |
| 712 | strsz = dyn->d_un.d_val; |
| 713 | continue; |
| 714 | |
| 715 | default: |
| 716 | continue; |
| 717 | |
| 718 | case DT_NULL: |
| 719 | break; |
| 720 | } |
| 721 | break; |
| 722 | } |
| 723 | |
| 724 | /* Translate pointers into file offsets. */ |
| 725 | GElf_Off offs[i_max] = { 0, }; |
| 726 | find_offsets (mod->main.elf, phnum, i_max, addrs, offs); |
| 727 | |
| 728 | /* Figure out the size of the symbol table. */ |
| 729 | if (offs[i_hash] != 0) |
| 730 | { |
| 731 | /* In the original format, .hash says the size of .dynsym. */ |
| 732 | |
| 733 | size_t entsz = SH_ENTSIZE_HASH (ehdr); |
| 734 | data = elf_getdata_rawchunk (mod->main.elf, |
| 735 | offs[i_hash] + entsz, entsz, |
| 736 | entsz == 4 ? ELF_T_WORD |
| 737 | : ELF_T_XWORD); |
| 738 | if (data != NULL) |
| 739 | mod->syments = (entsz == 4 |
| 740 | ? *(const GElf_Word *) data->d_buf |
| 741 | : *(const GElf_Xword *) data->d_buf); |
| 742 | } |
| 743 | if (offs[i_gnu_hash] != 0 && mod->syments == 0) |
| 744 | { |
| 745 | /* In the new format, we can derive it with some work. */ |
| 746 | |
| 747 | const struct |
| 748 | { |
| 749 | Elf32_Word nbuckets; |
| 750 | Elf32_Word symndx; |
| 751 | Elf32_Word maskwords; |
| 752 | Elf32_Word shift2; |
| 753 | } *header; |
| 754 | |
| 755 | data = elf_getdata_rawchunk (mod->main.elf, offs[i_gnu_hash], |
| 756 | sizeof *header, ELF_T_WORD); |
| 757 | if (data != NULL) |
| 758 | { |
| 759 | header = data->d_buf; |
| 760 | Elf32_Word nbuckets = header->nbuckets; |
| 761 | Elf32_Word symndx = header->symndx; |
| 762 | GElf_Off buckets_at = (offs[i_gnu_hash] + sizeof *header |
| 763 | + (gelf_getclass (mod->main.elf) |
| 764 | * sizeof (Elf32_Word) |
| 765 | * header->maskwords)); |
| 766 | |
| 767 | data = elf_getdata_rawchunk (mod->main.elf, buckets_at, |
| 768 | nbuckets * sizeof (Elf32_Word), |
| 769 | ELF_T_WORD); |
| 770 | if (data != NULL && symndx < nbuckets) |
| 771 | { |
| 772 | const Elf32_Word *const buckets = data->d_buf; |
| 773 | Elf32_Word maxndx = symndx; |
| 774 | for (Elf32_Word bucket = 0; bucket < nbuckets; ++bucket) |
| 775 | if (buckets[bucket] > maxndx) |
| 776 | maxndx = buckets[bucket]; |
| 777 | |
| 778 | GElf_Off hasharr_at = (buckets_at |
| 779 | + nbuckets * sizeof (Elf32_Word)); |
| 780 | hasharr_at += (maxndx - symndx) * sizeof (Elf32_Word); |
| 781 | do |
| 782 | { |
| 783 | data = elf_getdata_rawchunk (mod->main.elf, |
| 784 | hasharr_at, |
| 785 | sizeof (Elf32_Word), |
| 786 | ELF_T_WORD); |
| 787 | if (data != NULL |
| 788 | && (*(const Elf32_Word *) data->d_buf & 1u)) |
| 789 | { |
| 790 | mod->syments = maxndx + 1; |
| 791 | break; |
| 792 | } |
| 793 | ++maxndx; |
| 794 | hasharr_at += sizeof (Elf32_Word); |
| 795 | } while (data != NULL); |
| 796 | } |
| 797 | } |
| 798 | } |
| 799 | if (offs[i_strtab] > offs[i_symtab] && mod->syments == 0) |
| 800 | mod->syments = ((offs[i_strtab] - offs[i_symtab]) |
| 801 | / gelf_fsize (mod->main.elf, |
| 802 | ELF_T_SYM, 1, EV_CURRENT)); |
| 803 | |
| 804 | if (mod->syments > 0) |
| 805 | { |
| 806 | mod->symdata = elf_getdata_rawchunk (mod->main.elf, |
| 807 | offs[i_symtab], |
| 808 | gelf_fsize (mod->main.elf, |
| 809 | ELF_T_SYM, |
| 810 | mod->syments, |
| 811 | EV_CURRENT), |
| 812 | ELF_T_SYM); |
| 813 | if (mod->symdata != NULL) |
| 814 | { |
| 815 | mod->symstrdata = elf_getdata_rawchunk (mod->main.elf, |
| 816 | offs[i_strtab], |
| 817 | strsz, |
| 818 | ELF_T_BYTE); |
| 819 | if (mod->symstrdata == NULL) |
| 820 | mod->symdata = NULL; |
| 821 | } |
| 822 | if (mod->symdata == NULL) |
| 823 | mod->symerr = DWFL_E (LIBELF, elf_errno ()); |
| 824 | else |
| 825 | { |
| 826 | mod->symfile = &mod->main; |
| 827 | mod->symerr = DWFL_E_NOERROR; |
| 828 | } |
| 829 | return; |
| 830 | } |
| 831 | } |
| 832 | } |
| 833 | } |
| 834 | |
| 835 | /* Try to find a symbol table in either MOD->main.elf or MOD->debug.elf. */ |
| 836 | static void |
| 837 | find_symtab (Dwfl_Module *mod) |
| 838 | { |
| 839 | if (mod->symdata != NULL /* Already done. */ |
| 840 | || mod->symerr != DWFL_E_NOERROR) /* Cached previous failure. */ |
| 841 | return; |
| 842 | |
| 843 | __libdwfl_getelf (mod); |
| 844 | mod->symerr = mod->elferr; |
| 845 | if (mod->symerr != DWFL_E_NOERROR) |
| 846 | return; |
| 847 | |
| 848 | mod->first_global = -1; /* Unknown, unless explicitly set by load_symtab. */ |
| 849 | |
| 850 | /* First see if the main ELF file has the debugging information. */ |
| 851 | Elf_Scn *symscn = NULL, *xndxscn = NULL; |
| 852 | GElf_Word strshndx; |
| 853 | mod->symerr = load_symtab (&mod->main, &mod->symfile, &symscn, |
| 854 | &xndxscn, &mod->syments, &mod->first_global, |
| 855 | &strshndx); |
| 856 | switch (mod->symerr) |
| 857 | { |
| 858 | default: |
| 859 | return; |
| 860 | |
| 861 | case DWFL_E_NOERROR: |
| 862 | break; |
| 863 | |
| 864 | case DWFL_E_NO_SYMTAB: |
| 865 | /* Now we have to look for a separate debuginfo file. */ |
| 866 | mod->symerr = find_debuginfo (mod); |
| 867 | switch (mod->symerr) |
| 868 | { |
| 869 | default: |
| 870 | return; |
| 871 | |
| 872 | case DWFL_E_NOERROR: |
| 873 | mod->symerr = load_symtab (&mod->debug, &mod->symfile, &symscn, |
| 874 | &xndxscn, &mod->syments, |
| 875 | &mod->first_global, &strshndx); |
| 876 | break; |
| 877 | |
| 878 | case DWFL_E_CB: /* The find_debuginfo hook failed. */ |
| 879 | mod->symerr = DWFL_E_NO_SYMTAB; |
| 880 | break; |
| 881 | } |
| 882 | |
| 883 | switch (mod->symerr) |
| 884 | { |
| 885 | default: |
| 886 | return; |
| 887 | |
| 888 | case DWFL_E_NOERROR: |
| 889 | break; |
| 890 | |
| 891 | case DWFL_E_NO_SYMTAB: |
| 892 | if (symscn != NULL) |
| 893 | { |
| 894 | /* We still have the dynamic symbol table. */ |
| 895 | mod->symerr = DWFL_E_NOERROR; |
| 896 | break; |
| 897 | } |
| 898 | |
| 899 | /* Last ditch, look for dynamic symbols without section headers. */ |
| 900 | find_dynsym (mod); |
| 901 | return; |
| 902 | } |
| 903 | break; |
| 904 | } |
| 905 | |
| 906 | /* This does some sanity checks on the string table section. */ |
| 907 | if (elf_strptr (mod->symfile->elf, strshndx, 0) == NULL) |
| 908 | { |
| 909 | elferr: |
| 910 | mod->symerr = DWFL_E (LIBELF, elf_errno ()); |
| 911 | return; |
| 912 | } |
| 913 | |
| 914 | /* Cache the data; MOD->syments and MOD->first_global were set above. */ |
| 915 | |
| 916 | mod->symstrdata = elf_getdata (elf_getscn (mod->symfile->elf, strshndx), |
| 917 | NULL); |
| 918 | if (mod->symstrdata == NULL) |
| 919 | goto elferr; |
| 920 | |
| 921 | if (xndxscn == NULL) |
| 922 | mod->symxndxdata = NULL; |
| 923 | else |
| 924 | { |
| 925 | mod->symxndxdata = elf_getdata (xndxscn, NULL); |
| 926 | if (mod->symxndxdata == NULL) |
| 927 | goto elferr; |
| 928 | } |
| 929 | |
| 930 | mod->symdata = elf_getdata (symscn, NULL); |
| 931 | if (mod->symdata == NULL) |
| 932 | goto elferr; |
| 933 | } |
| 934 | |
| 935 | |
| 936 | /* Try to open a libebl backend for MOD. */ |
| 937 | Dwfl_Error |
| 938 | internal_function |
| 939 | __libdwfl_module_getebl (Dwfl_Module *mod) |
| 940 | { |
| 941 | if (mod->ebl == NULL) |
| 942 | { |
| 943 | __libdwfl_getelf (mod); |
| 944 | if (mod->elferr != DWFL_E_NOERROR) |
| 945 | return mod->elferr; |
| 946 | |
| 947 | mod->ebl = ebl_openbackend (mod->main.elf); |
| 948 | if (mod->ebl == NULL) |
| 949 | return DWFL_E_LIBEBL; |
| 950 | } |
| 951 | return DWFL_E_NOERROR; |
| 952 | } |
| 953 | |
| 954 | /* Try to start up libdw on DEBUGFILE. */ |
| 955 | static Dwfl_Error |
| 956 | load_dw (Dwfl_Module *mod, struct dwfl_file *debugfile) |
| 957 | { |
| 958 | if (mod->e_type == ET_REL && !debugfile->relocated) |
| 959 | { |
| 960 | const Dwfl_Callbacks *const cb = mod->dwfl->callbacks; |
| 961 | |
| 962 | /* The debugging sections have to be relocated. */ |
| 963 | if (cb->section_address == NULL) |
| 964 | return DWFL_E_NOREL; |
| 965 | |
| 966 | Dwfl_Error error = __libdwfl_module_getebl (mod); |
| 967 | if (error != DWFL_E_NOERROR) |
| 968 | return error; |
| 969 | |
| 970 | find_symtab (mod); |
| 971 | Dwfl_Error result = mod->symerr; |
| 972 | if (result == DWFL_E_NOERROR) |
| 973 | result = __libdwfl_relocate (mod, debugfile->elf, true); |
| 974 | if (result != DWFL_E_NOERROR) |
| 975 | return result; |
| 976 | |
| 977 | /* Don't keep the file descriptors around. */ |
| 978 | if (mod->main.fd != -1 && elf_cntl (mod->main.elf, ELF_C_FDREAD) == 0) |
| 979 | { |
| 980 | close (mod->main.fd); |
| 981 | mod->main.fd = -1; |
| 982 | } |
| 983 | if (debugfile->fd != -1 && elf_cntl (debugfile->elf, ELF_C_FDREAD) == 0) |
| 984 | { |
| 985 | close (debugfile->fd); |
| 986 | debugfile->fd = -1; |
| 987 | } |
| 988 | } |
| 989 | |
| 990 | mod->dw = INTUSE(dwarf_begin_elf) (debugfile->elf, DWARF_C_READ, NULL); |
| 991 | if (mod->dw == NULL) |
| 992 | { |
| 993 | int err = INTUSE(dwarf_errno) (); |
| 994 | return err == DWARF_E_NO_DWARF ? DWFL_E_NO_DWARF : DWFL_E (LIBDW, err); |
| 995 | } |
| 996 | |
| 997 | /* Until we have iterated through all CU's, we might do lazy lookups. */ |
| 998 | mod->lazycu = 1; |
| 999 | |
| 1000 | return DWFL_E_NOERROR; |
| 1001 | } |
| 1002 | |
| 1003 | /* Try to start up libdw on either the main file or the debuginfo file. */ |
| 1004 | static void |
| 1005 | find_dw (Dwfl_Module *mod) |
| 1006 | { |
| 1007 | if (mod->dw != NULL /* Already done. */ |
| 1008 | || mod->dwerr != DWFL_E_NOERROR) /* Cached previous failure. */ |
| 1009 | return; |
| 1010 | |
| 1011 | __libdwfl_getelf (mod); |
| 1012 | mod->dwerr = mod->elferr; |
| 1013 | if (mod->dwerr != DWFL_E_NOERROR) |
| 1014 | return; |
| 1015 | |
| 1016 | /* First see if the main ELF file has the debugging information. */ |
| 1017 | mod->dwerr = load_dw (mod, &mod->main); |
| 1018 | switch (mod->dwerr) |
| 1019 | { |
| 1020 | case DWFL_E_NOERROR: |
| 1021 | mod->debug.elf = mod->main.elf; |
| 1022 | mod->debug.address_sync = mod->main.address_sync; |
| 1023 | return; |
| 1024 | |
| 1025 | case DWFL_E_NO_DWARF: |
| 1026 | break; |
| 1027 | |
| 1028 | default: |
| 1029 | goto canonicalize; |
| 1030 | } |
| 1031 | |
| 1032 | /* Now we have to look for a separate debuginfo file. */ |
| 1033 | mod->dwerr = find_debuginfo (mod); |
| 1034 | switch (mod->dwerr) |
| 1035 | { |
| 1036 | case DWFL_E_NOERROR: |
| 1037 | mod->dwerr = load_dw (mod, &mod->debug); |
| 1038 | break; |
| 1039 | |
| 1040 | case DWFL_E_CB: /* The find_debuginfo hook failed. */ |
| 1041 | mod->dwerr = DWFL_E_NO_DWARF; |
| 1042 | return; |
| 1043 | |
| 1044 | default: |
| 1045 | break; |
| 1046 | } |
| 1047 | |
| 1048 | canonicalize: |
| 1049 | mod->dwerr = __libdwfl_canon_error (mod->dwerr); |
| 1050 | } |
| 1051 | |
| 1052 | Dwarf * |
| 1053 | dwfl_module_getdwarf (Dwfl_Module *mod, Dwarf_Addr *bias) |
| 1054 | { |
| 1055 | if (mod == NULL) |
| 1056 | return NULL; |
| 1057 | |
| 1058 | find_dw (mod); |
| 1059 | if (mod->dwerr == DWFL_E_NOERROR) |
| 1060 | { |
| 1061 | /* If dwfl_module_getelf was used previously, then partial apply |
| 1062 | relocation to miscellaneous sections in the debug file too. */ |
| 1063 | if (mod->e_type == ET_REL |
| 1064 | && mod->main.relocated && ! mod->debug.relocated) |
| 1065 | { |
| 1066 | mod->debug.relocated = true; |
| 1067 | if (mod->debug.elf != mod->main.elf) |
| 1068 | (void) __libdwfl_relocate (mod, mod->debug.elf, false); |
| 1069 | } |
| 1070 | |
| 1071 | *bias = dwfl_adjusted_dwarf_addr (mod, 0); |
| 1072 | return mod->dw; |
| 1073 | } |
| 1074 | |
| 1075 | __libdwfl_seterrno (mod->dwerr); |
| 1076 | return NULL; |
| 1077 | } |
| 1078 | INTDEF (dwfl_module_getdwarf) |
| 1079 | |
| 1080 | int |
| 1081 | dwfl_module_getsymtab (Dwfl_Module *mod) |
| 1082 | { |
| 1083 | if (mod == NULL) |
| 1084 | return -1; |
| 1085 | |
| 1086 | find_symtab (mod); |
| 1087 | if (mod->symerr == DWFL_E_NOERROR) |
| 1088 | return mod->syments; |
| 1089 | |
| 1090 | __libdwfl_seterrno (mod->symerr); |
| 1091 | return -1; |
| 1092 | } |
| 1093 | INTDEF (dwfl_module_getsymtab) |