Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 1 | /* Report modules by examining dynamic linker data structures. |
Mark Wielaard | f592035 | 2015-05-22 18:31:58 +0200 | [diff] [blame] | 2 | Copyright (C) 2008-2015 Red Hat, Inc. |
Mark Wielaard | de2ed97 | 2012-06-05 17:15:16 +0200 | [diff] [blame] | 3 | This file is part of elfutils. |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 4 | |
Mark Wielaard | de2ed97 | 2012-06-05 17:15:16 +0200 | [diff] [blame] | 5 | This file is free software; you can redistribute it and/or modify |
| 6 | it under the terms of either |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 7 | |
Mark Wielaard | de2ed97 | 2012-06-05 17:15:16 +0200 | [diff] [blame] | 8 | * the GNU Lesser General Public License as published by the Free |
| 9 | Software Foundation; either version 3 of the License, or (at |
| 10 | your option) any later version |
| 11 | |
| 12 | or |
| 13 | |
| 14 | * the GNU General Public License as published by the Free |
| 15 | Software Foundation; either version 2 of the License, or (at |
| 16 | your option) any later version |
| 17 | |
| 18 | or both in parallel, as here. |
| 19 | |
| 20 | elfutils is distributed in the hope that it will be useful, but |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 21 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 22 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 23 | General Public License for more details. |
| 24 | |
Mark Wielaard | de2ed97 | 2012-06-05 17:15:16 +0200 | [diff] [blame] | 25 | You should have received copies of the GNU General Public License and |
| 26 | the GNU Lesser General Public License along with this program. If |
| 27 | not, see <http://www.gnu.org/licenses/>. */ |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 28 | |
| 29 | #include <config.h> |
| 30 | #include "libdwflP.h" |
Roland McGrath | 3999ce1 | 2013-01-07 14:53:37 -0800 | [diff] [blame] | 31 | #include "../libdw/memory-access.h" |
Mark Wielaard | 9efa9e6 | 2013-04-27 20:50:32 +0200 | [diff] [blame] | 32 | #include "system.h" |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 33 | |
| 34 | #include <byteswap.h> |
| 35 | #include <endian.h> |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 36 | #include <fcntl.h> |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 37 | |
| 38 | /* This element is always provided and always has a constant value. |
| 39 | This makes it an easy thing to scan for to discern the format. */ |
| 40 | #define PROBE_TYPE AT_PHENT |
| 41 | #define PROBE_VAL32 sizeof (Elf32_Phdr) |
| 42 | #define PROBE_VAL64 sizeof (Elf64_Phdr) |
| 43 | |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 44 | |
Chih-Hung Hsieh | e3bfee6 | 2015-11-17 14:45:15 -0800 | [diff] [blame] | 45 | static inline bool |
| 46 | do_check64 (size_t i, const Elf64_auxv_t (*a64)[], uint_fast8_t *elfdata) |
| 47 | { |
| 48 | /* The AUXV pointer might not even be naturally aligned for 64-bit |
| 49 | data, because note payloads in a core file are not aligned. */ |
| 50 | |
| 51 | uint64_t type = read_8ubyte_unaligned_noncvt (&(*a64)[i].a_type); |
| 52 | uint64_t val = read_8ubyte_unaligned_noncvt (&(*a64)[i].a_un.a_val); |
| 53 | |
| 54 | if (type == BE64 (PROBE_TYPE) |
| 55 | && val == BE64 (PROBE_VAL64)) |
| 56 | { |
| 57 | *elfdata = ELFDATA2MSB; |
| 58 | return true; |
| 59 | } |
| 60 | |
| 61 | if (type == LE64 (PROBE_TYPE) |
| 62 | && val == LE64 (PROBE_VAL64)) |
| 63 | { |
| 64 | *elfdata = ELFDATA2LSB; |
| 65 | return true; |
| 66 | } |
| 67 | |
| 68 | return false; |
| 69 | } |
| 70 | |
| 71 | #define check64(n) do_check64 (n, a64, elfdata) |
| 72 | |
| 73 | static inline bool |
| 74 | do_check32 (size_t i, const Elf32_auxv_t (*a32)[], uint_fast8_t *elfdata) |
| 75 | { |
| 76 | /* The AUXV pointer might not even be naturally aligned for 32-bit |
| 77 | data, because note payloads in a core file are not aligned. */ |
| 78 | |
| 79 | uint32_t type = read_4ubyte_unaligned_noncvt (&(*a32)[i].a_type); |
| 80 | uint32_t val = read_4ubyte_unaligned_noncvt (&(*a32)[i].a_un.a_val); |
| 81 | |
| 82 | if (type == BE32 (PROBE_TYPE) |
| 83 | && val == BE32 (PROBE_VAL32)) |
| 84 | { |
| 85 | *elfdata = ELFDATA2MSB; |
| 86 | return true; |
| 87 | } |
| 88 | |
| 89 | if (type == LE32 (PROBE_TYPE) |
| 90 | && val == LE32 (PROBE_VAL32)) |
| 91 | { |
| 92 | *elfdata = ELFDATA2LSB; |
| 93 | return true; |
| 94 | } |
| 95 | |
| 96 | return false; |
| 97 | } |
| 98 | |
| 99 | #define check32(n) do_check32 (n, a32, elfdata) |
| 100 | |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 101 | /* Examine an auxv data block and determine its format. |
| 102 | Return true iff we figured it out. */ |
| 103 | static bool |
| 104 | auxv_format_probe (const void *auxv, size_t size, |
| 105 | uint_fast8_t *elfclass, uint_fast8_t *elfdata) |
| 106 | { |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 107 | const Elf32_auxv_t (*a32)[size / sizeof (Elf32_auxv_t)] = (void *) auxv; |
| 108 | const Elf64_auxv_t (*a64)[size / sizeof (Elf64_auxv_t)] = (void *) auxv; |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 109 | |
Roland McGrath | 5ea349b | 2010-04-06 00:04:49 -0700 | [diff] [blame] | 110 | for (size_t i = 0; i < size / sizeof (Elf64_auxv_t); ++i) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 111 | { |
| 112 | if (check64 (i)) |
| 113 | { |
| 114 | *elfclass = ELFCLASS64; |
| 115 | return true; |
| 116 | } |
| 117 | |
Roland McGrath | 5ea349b | 2010-04-06 00:04:49 -0700 | [diff] [blame] | 118 | if (check32 (i * 2) || check32 (i * 2 + 1)) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 119 | { |
| 120 | *elfclass = ELFCLASS32; |
| 121 | return true; |
| 122 | } |
| 123 | } |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 124 | |
| 125 | return false; |
| 126 | } |
| 127 | |
| 128 | /* This is a Dwfl_Memory_Callback that wraps another memory callback. |
| 129 | If the underlying callback cannot fill the data, then this will |
| 130 | fall back to fetching data from module files. */ |
| 131 | |
| 132 | struct integrated_memory_callback |
| 133 | { |
| 134 | Dwfl_Memory_Callback *memory_callback; |
| 135 | void *memory_callback_arg; |
| 136 | void *buffer; |
| 137 | }; |
| 138 | |
| 139 | static bool |
| 140 | integrated_memory_callback (Dwfl *dwfl, int ndx, |
| 141 | void **buffer, size_t *buffer_available, |
| 142 | GElf_Addr vaddr, |
| 143 | size_t minread, |
| 144 | void *arg) |
| 145 | { |
| 146 | struct integrated_memory_callback *info = arg; |
| 147 | |
| 148 | if (ndx == -1) |
| 149 | { |
| 150 | /* Called for cleanup. */ |
| 151 | if (info->buffer != NULL) |
| 152 | { |
| 153 | /* The last probe buffer came from the underlying callback. |
| 154 | Let it do its cleanup. */ |
| 155 | assert (*buffer == info->buffer); /* XXX */ |
| 156 | *buffer = info->buffer; |
| 157 | info->buffer = NULL; |
| 158 | return (*info->memory_callback) (dwfl, ndx, buffer, buffer_available, |
| 159 | vaddr, minread, |
| 160 | info->memory_callback_arg); |
| 161 | } |
| 162 | *buffer = NULL; |
| 163 | *buffer_available = 0; |
| 164 | return false; |
| 165 | } |
| 166 | |
| 167 | if (*buffer != NULL) |
| 168 | /* For a final-read request, we only use the underlying callback. */ |
| 169 | return (*info->memory_callback) (dwfl, ndx, buffer, buffer_available, |
| 170 | vaddr, minread, info->memory_callback_arg); |
| 171 | |
| 172 | /* Let the underlying callback try to fill this request. */ |
| 173 | if ((*info->memory_callback) (dwfl, ndx, &info->buffer, buffer_available, |
| 174 | vaddr, minread, info->memory_callback_arg)) |
| 175 | { |
| 176 | *buffer = info->buffer; |
| 177 | return true; |
| 178 | } |
| 179 | |
| 180 | /* Now look for module text covering this address. */ |
| 181 | |
| 182 | Dwfl_Module *mod; |
| 183 | (void) INTUSE(dwfl_addrsegment) (dwfl, vaddr, &mod); |
| 184 | if (mod == NULL) |
| 185 | return false; |
| 186 | |
| 187 | Dwarf_Addr bias; |
| 188 | Elf_Scn *scn = INTUSE(dwfl_module_address_section) (mod, &vaddr, &bias); |
| 189 | if (unlikely (scn == NULL)) |
| 190 | { |
| 191 | #if 0 // XXX would have to handle ndx=-1 cleanup calls passed down. |
| 192 | /* If we have no sections we can try to fill it from the module file |
| 193 | based on its phdr mappings. */ |
| 194 | if (likely (mod->e_type != ET_REL) && mod->main.elf != NULL) |
| 195 | return INTUSE(dwfl_elf_phdr_memory_callback) |
| 196 | (dwfl, 0, buffer, buffer_available, |
| 197 | vaddr - mod->main.bias, minread, mod->main.elf); |
| 198 | #endif |
| 199 | return false; |
| 200 | } |
| 201 | |
| 202 | Elf_Data *data = elf_rawdata (scn, NULL); |
| 203 | if (unlikely (data == NULL)) |
| 204 | // XXX throw error? |
| 205 | return false; |
| 206 | |
| 207 | if (unlikely (data->d_size < vaddr)) |
| 208 | return false; |
| 209 | |
| 210 | /* Provide as much data as we have. */ |
| 211 | void *contents = data->d_buf + vaddr; |
| 212 | size_t avail = data->d_size - vaddr; |
| 213 | if (unlikely (avail < minread)) |
| 214 | return false; |
| 215 | |
| 216 | /* If probing for a string, make sure it's terminated. */ |
| 217 | if (minread == 0 && unlikely (memchr (contents, '\0', avail) == NULL)) |
| 218 | return false; |
| 219 | |
| 220 | /* We have it! */ |
| 221 | *buffer = contents; |
| 222 | *buffer_available = avail; |
| 223 | return true; |
| 224 | } |
| 225 | |
| 226 | static size_t |
| 227 | addrsize (uint_fast8_t elfclass) |
| 228 | { |
| 229 | return elfclass * 4; |
| 230 | } |
| 231 | |
| 232 | /* Report a module for each struct link_map in the linked list at r_map |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 233 | in the struct r_debug at R_DEBUG_VADDR. For r_debug_info description |
Jan Kratochvil | 596d430 | 2013-07-23 16:30:01 +0200 | [diff] [blame] | 234 | see dwfl_link_map_report in libdwflP.h. If R_DEBUG_INFO is not NULL then no |
| 235 | modules get added to DWFL, caller has to add them from filled in |
| 236 | R_DEBUG_INFO. |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 237 | |
| 238 | For each link_map entry, if an existing module resides at its address, |
| 239 | this just modifies that module's name and suggested file name. If |
| 240 | no such module exists, this calls dwfl_report_elf on the l_name string. |
| 241 | |
| 242 | Returns the number of modules found, or -1 for errors. */ |
| 243 | |
| 244 | static int |
| 245 | report_r_debug (uint_fast8_t elfclass, uint_fast8_t elfdata, |
| 246 | Dwfl *dwfl, GElf_Addr r_debug_vaddr, |
| 247 | Dwfl_Memory_Callback *memory_callback, |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 248 | void *memory_callback_arg, |
| 249 | struct r_debug_info *r_debug_info) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 250 | { |
| 251 | /* Skip r_version, to aligned r_map field. */ |
| 252 | GElf_Addr read_vaddr = r_debug_vaddr + addrsize (elfclass); |
| 253 | |
| 254 | void *buffer = NULL; |
| 255 | size_t buffer_available = 0; |
| 256 | inline int release_buffer (int result) |
| 257 | { |
| 258 | if (buffer != NULL) |
| 259 | (void) (*memory_callback) (dwfl, -1, &buffer, &buffer_available, 0, 0, |
| 260 | memory_callback_arg); |
| 261 | return result; |
| 262 | } |
| 263 | |
| 264 | GElf_Addr addrs[4]; |
| 265 | inline bool read_addrs (GElf_Addr vaddr, size_t n) |
| 266 | { |
| 267 | size_t nb = n * addrsize (elfclass); /* Address words -> bytes to read. */ |
| 268 | |
| 269 | /* Read a new buffer if the old one doesn't cover these words. */ |
| 270 | if (buffer == NULL |
| 271 | || vaddr < read_vaddr |
| 272 | || vaddr - read_vaddr + nb > buffer_available) |
| 273 | { |
| 274 | release_buffer (0); |
| 275 | |
| 276 | read_vaddr = vaddr; |
| 277 | int segndx = INTUSE(dwfl_addrsegment) (dwfl, vaddr, NULL); |
| 278 | if (unlikely (segndx < 0) |
| 279 | || unlikely (! (*memory_callback) (dwfl, segndx, |
| 280 | &buffer, &buffer_available, |
| 281 | vaddr, nb, memory_callback_arg))) |
| 282 | return true; |
| 283 | } |
| 284 | |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 285 | Elf32_Addr (*a32)[n] = vaddr - read_vaddr + buffer; |
| 286 | Elf64_Addr (*a64)[n] = (void *) a32; |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 287 | |
| 288 | if (elfclass == ELFCLASS32) |
| 289 | { |
| 290 | if (elfdata == ELFDATA2MSB) |
| 291 | for (size_t i = 0; i < n; ++i) |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 292 | addrs[i] = BE32 (read_4ubyte_unaligned_noncvt (&(*a32)[i])); |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 293 | else |
| 294 | for (size_t i = 0; i < n; ++i) |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 295 | addrs[i] = LE32 (read_4ubyte_unaligned_noncvt (&(*a32)[i])); |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 296 | } |
| 297 | else |
| 298 | { |
| 299 | if (elfdata == ELFDATA2MSB) |
| 300 | for (size_t i = 0; i < n; ++i) |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 301 | addrs[i] = BE64 (read_8ubyte_unaligned_noncvt (&(*a64)[i])); |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 302 | else |
| 303 | for (size_t i = 0; i < n; ++i) |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 304 | addrs[i] = LE64 (read_8ubyte_unaligned_noncvt (&(*a64)[i])); |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 305 | } |
| 306 | |
| 307 | return false; |
| 308 | } |
| 309 | |
| 310 | if (unlikely (read_addrs (read_vaddr, 1))) |
| 311 | return release_buffer (-1); |
| 312 | |
| 313 | GElf_Addr next = addrs[0]; |
| 314 | |
| 315 | Dwfl_Module **lastmodp = &dwfl->modulelist; |
| 316 | int result = 0; |
Roland McGrath | be13930 | 2010-04-14 12:54:45 -0700 | [diff] [blame] | 317 | |
| 318 | /* There can't be more elements in the link_map list than there are |
| 319 | segments. DWFL->lookup_elts is probably twice that number, so it |
| 320 | is certainly above the upper bound. If we iterate too many times, |
| 321 | there must be a loop in the pointers due to link_map clobberation. */ |
| 322 | size_t iterations = 0; |
| 323 | while (next != 0 && ++iterations < dwfl->lookup_elts) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 324 | { |
| 325 | if (read_addrs (next, 4)) |
| 326 | return release_buffer (-1); |
| 327 | |
Jan Kratochvil | 475849f | 2014-07-24 20:47:17 +0200 | [diff] [blame] | 328 | /* Unused: l_addr is the difference between the address in memory |
| 329 | and the ELF file when the core was created. We need to |
| 330 | recalculate the difference below because the ELF file we use |
| 331 | might be differently pre-linked. */ |
| 332 | // GElf_Addr l_addr = addrs[0]; |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 333 | GElf_Addr l_name = addrs[1]; |
| 334 | GElf_Addr l_ld = addrs[2]; |
| 335 | next = addrs[3]; |
| 336 | |
Roland McGrath | cdb48e0 | 2009-11-05 11:34:08 -0800 | [diff] [blame] | 337 | /* If a clobbered or truncated memory image has no useful pointer, |
| 338 | just skip this element. */ |
| 339 | if (l_ld == 0) |
| 340 | continue; |
| 341 | |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 342 | /* Fetch the string at the l_name address. */ |
| 343 | const char *name = NULL; |
| 344 | if (buffer != NULL |
| 345 | && read_vaddr <= l_name |
| 346 | && l_name + 1 - read_vaddr < buffer_available |
| 347 | && memchr (l_name - read_vaddr + buffer, '\0', |
| 348 | buffer_available - (l_name - read_vaddr)) != NULL) |
| 349 | name = l_name - read_vaddr + buffer; |
| 350 | else |
| 351 | { |
| 352 | release_buffer (0); |
| 353 | read_vaddr = l_name; |
| 354 | int segndx = INTUSE(dwfl_addrsegment) (dwfl, l_name, NULL); |
| 355 | if (likely (segndx >= 0) |
| 356 | && (*memory_callback) (dwfl, segndx, |
| 357 | &buffer, &buffer_available, |
| 358 | l_name, 0, memory_callback_arg)) |
| 359 | name = buffer; |
| 360 | } |
| 361 | |
| 362 | if (name != NULL && name[0] == '\0') |
| 363 | name = NULL; |
| 364 | |
Mark Wielaard | 355b408 | 2015-12-01 22:16:00 +0100 | [diff] [blame] | 365 | if (iterations == 1 |
| 366 | && dwfl->user_core != NULL |
| 367 | && dwfl->user_core->executable_for_core != NULL) |
| 368 | name = dwfl->user_core->executable_for_core; |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 369 | |
Jan Kratochvil | 596d430 | 2013-07-23 16:30:01 +0200 | [diff] [blame] | 370 | struct r_debug_info_module *r_debug_info_module = NULL; |
| 371 | if (r_debug_info != NULL) |
| 372 | { |
| 373 | /* Save link map information about valid shared library (or |
| 374 | executable) which has not been found on disk. */ |
| 375 | const char *name1 = name == NULL ? "" : name; |
| 376 | r_debug_info_module = malloc (sizeof (*r_debug_info_module) |
| 377 | + strlen (name1) + 1); |
Mark Wielaard | f592035 | 2015-05-22 18:31:58 +0200 | [diff] [blame] | 378 | if (unlikely (r_debug_info_module == NULL)) |
Jan Kratochvil | 596d430 | 2013-07-23 16:30:01 +0200 | [diff] [blame] | 379 | return release_buffer (result); |
| 380 | r_debug_info_module->fd = -1; |
| 381 | r_debug_info_module->elf = NULL; |
Jan Kratochvil | 596d430 | 2013-07-23 16:30:01 +0200 | [diff] [blame] | 382 | r_debug_info_module->l_ld = l_ld; |
| 383 | r_debug_info_module->start = 0; |
| 384 | r_debug_info_module->end = 0; |
| 385 | r_debug_info_module->disk_file_has_build_id = false; |
| 386 | strcpy (r_debug_info_module->name, name1); |
| 387 | r_debug_info_module->next = r_debug_info->module; |
| 388 | r_debug_info->module = r_debug_info_module; |
| 389 | } |
| 390 | |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 391 | Dwfl_Module *mod = NULL; |
| 392 | if (name != NULL) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 393 | { |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 394 | /* This code is mostly inlined dwfl_report_elf. */ |
| 395 | // XXX hook for sysroot |
Josh Stone | 3425454 | 2015-10-09 10:10:37 -0700 | [diff] [blame] | 396 | int fd = open (name, O_RDONLY); |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 397 | if (fd >= 0) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 398 | { |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 399 | Elf *elf; |
| 400 | Dwfl_Error error = __libdw_open_file (&fd, &elf, true, false); |
Jan Kratochvil | 463e983 | 2013-11-21 15:28:02 +0100 | [diff] [blame] | 401 | GElf_Addr elf_dynamic_vaddr; |
| 402 | if (error == DWFL_E_NOERROR |
| 403 | && __libdwfl_dynamic_vaddr_get (elf, &elf_dynamic_vaddr)) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 404 | { |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 405 | const void *build_id_bits; |
| 406 | GElf_Addr build_id_elfaddr; |
| 407 | int build_id_len; |
| 408 | bool valid = true; |
| 409 | |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 410 | if (__libdwfl_find_elf_build_id (NULL, elf, &build_id_bits, |
| 411 | &build_id_elfaddr, |
| 412 | &build_id_len) > 0 |
| 413 | && build_id_elfaddr != 0) |
| 414 | { |
Jan Kratochvil | 596d430 | 2013-07-23 16:30:01 +0200 | [diff] [blame] | 415 | if (r_debug_info_module != NULL) |
| 416 | r_debug_info_module->disk_file_has_build_id = true; |
Jan Kratochvil | 463e983 | 2013-11-21 15:28:02 +0100 | [diff] [blame] | 417 | GElf_Addr build_id_vaddr = (build_id_elfaddr |
| 418 | - elf_dynamic_vaddr + l_ld); |
| 419 | |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 420 | release_buffer (0); |
| 421 | int segndx = INTUSE(dwfl_addrsegment) (dwfl, |
| 422 | build_id_vaddr, |
| 423 | NULL); |
| 424 | if (! (*memory_callback) (dwfl, segndx, |
| 425 | &buffer, &buffer_available, |
| 426 | build_id_vaddr, build_id_len, |
Mark Wielaard | 24b26ec | 2013-06-05 17:03:25 +0200 | [diff] [blame] | 427 | memory_callback_arg)) |
Jan Kratochvil | 99a2949 | 2013-11-21 15:33:22 +0100 | [diff] [blame] | 428 | { |
| 429 | /* File has valid build-id which cannot be read from |
| 430 | memory. This happens for core files without bit 4 |
| 431 | (0x10) set in Linux /proc/PID/coredump_filter. */ |
| 432 | } |
Mark Wielaard | 24b26ec | 2013-06-05 17:03:25 +0200 | [diff] [blame] | 433 | else |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 434 | { |
Mark Wielaard | 24b26ec | 2013-06-05 17:03:25 +0200 | [diff] [blame] | 435 | if (memcmp (build_id_bits, buffer, build_id_len) != 0) |
| 436 | /* File has valid build-id which does not match |
| 437 | the one in memory. */ |
| 438 | valid = false; |
| 439 | release_buffer (0); |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 440 | } |
| 441 | } |
| 442 | |
| 443 | if (valid) |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 444 | { |
Jan Kratochvil | 475849f | 2014-07-24 20:47:17 +0200 | [diff] [blame] | 445 | // It is like l_addr but it handles differently prelinked |
| 446 | // files at core dumping vs. core loading time. |
| 447 | GElf_Addr base = l_ld - elf_dynamic_vaddr; |
Jan Kratochvil | 596d430 | 2013-07-23 16:30:01 +0200 | [diff] [blame] | 448 | if (r_debug_info_module == NULL) |
| 449 | { |
| 450 | // XXX hook for sysroot |
| 451 | mod = __libdwfl_report_elf (dwfl, basename (name), |
Jan Kratochvil | 475849f | 2014-07-24 20:47:17 +0200 | [diff] [blame] | 452 | name, fd, elf, base, |
Jan Kratochvil | 596d430 | 2013-07-23 16:30:01 +0200 | [diff] [blame] | 453 | true, true); |
| 454 | if (mod != NULL) |
| 455 | { |
| 456 | elf = NULL; |
| 457 | fd = -1; |
| 458 | } |
| 459 | } |
Jan Kratochvil | 475849f | 2014-07-24 20:47:17 +0200 | [diff] [blame] | 460 | else if (__libdwfl_elf_address_range (elf, base, true, |
Jan Kratochvil | 596d430 | 2013-07-23 16:30:01 +0200 | [diff] [blame] | 461 | true, NULL, NULL, |
| 462 | &r_debug_info_module->start, |
| 463 | &r_debug_info_module->end, |
| 464 | NULL, NULL)) |
| 465 | { |
| 466 | r_debug_info_module->elf = elf; |
| 467 | r_debug_info_module->fd = fd; |
| 468 | elf = NULL; |
| 469 | fd = -1; |
| 470 | } |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 471 | } |
Jan Kratochvil | 596d430 | 2013-07-23 16:30:01 +0200 | [diff] [blame] | 472 | if (elf != NULL) |
| 473 | elf_end (elf); |
| 474 | if (fd != -1) |
| 475 | close (fd); |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 476 | } |
| 477 | } |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 478 | } |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 479 | |
| 480 | if (mod != NULL) |
| 481 | { |
| 482 | ++result; |
| 483 | |
| 484 | /* Move this module to the end of the list, so that we end |
| 485 | up with a list in the same order as the link_map chain. */ |
| 486 | if (mod->next != NULL) |
| 487 | { |
| 488 | if (*lastmodp != mod) |
| 489 | { |
| 490 | lastmodp = &dwfl->modulelist; |
| 491 | while (*lastmodp != mod) |
| 492 | lastmodp = &(*lastmodp)->next; |
| 493 | } |
| 494 | *lastmodp = mod->next; |
| 495 | mod->next = NULL; |
| 496 | while (*lastmodp != NULL) |
| 497 | lastmodp = &(*lastmodp)->next; |
| 498 | *lastmodp = mod; |
| 499 | } |
| 500 | |
| 501 | lastmodp = &mod->next; |
| 502 | } |
| 503 | } |
| 504 | |
| 505 | return release_buffer (result); |
| 506 | } |
| 507 | |
| 508 | static GElf_Addr |
| 509 | consider_executable (Dwfl_Module *mod, GElf_Addr at_phdr, GElf_Addr at_entry, |
| 510 | uint_fast8_t *elfclass, uint_fast8_t *elfdata, |
| 511 | Dwfl_Memory_Callback *memory_callback, |
| 512 | void *memory_callback_arg) |
| 513 | { |
| 514 | GElf_Ehdr ehdr; |
| 515 | if (unlikely (gelf_getehdr (mod->main.elf, &ehdr) == NULL)) |
| 516 | return 0; |
| 517 | |
| 518 | if (at_entry != 0) |
| 519 | { |
| 520 | /* If we have an AT_ENTRY value, reject this executable if |
| 521 | its entry point address could not have supplied that. */ |
| 522 | |
| 523 | if (ehdr.e_entry == 0) |
| 524 | return 0; |
| 525 | |
| 526 | if (mod->e_type == ET_EXEC) |
| 527 | { |
| 528 | if (ehdr.e_entry != at_entry) |
| 529 | return 0; |
| 530 | } |
| 531 | else |
| 532 | { |
| 533 | /* It could be a PIE. */ |
| 534 | } |
| 535 | } |
| 536 | |
| 537 | // XXX this could be saved in the file cache: phdr vaddr, DT_DEBUG d_val vaddr |
| 538 | /* Find the vaddr of the DT_DEBUG's d_ptr. This is the memory |
| 539 | address where &r_debug was written at runtime. */ |
| 540 | GElf_Xword align = mod->dwfl->segment_align; |
| 541 | GElf_Addr d_val_vaddr = 0; |
Mark Wielaard | 712c8fa | 2014-11-22 23:08:48 +0100 | [diff] [blame] | 542 | size_t phnum; |
| 543 | if (elf_getphdrnum (mod->main.elf, &phnum) != 0) |
| 544 | return 0; |
| 545 | |
| 546 | for (size_t i = 0; i < phnum; ++i) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 547 | { |
| 548 | GElf_Phdr phdr_mem; |
| 549 | GElf_Phdr *phdr = gelf_getphdr (mod->main.elf, i, &phdr_mem); |
| 550 | if (phdr == NULL) |
| 551 | break; |
| 552 | |
| 553 | if (phdr->p_align > 1 && (align == 0 || phdr->p_align < align)) |
| 554 | align = phdr->p_align; |
| 555 | |
| 556 | if (at_phdr != 0 |
| 557 | && phdr->p_type == PT_LOAD |
| 558 | && (phdr->p_offset & -align) == (ehdr.e_phoff & -align)) |
| 559 | { |
| 560 | /* This is the segment that would map the phdrs. |
| 561 | If we have an AT_PHDR value, reject this executable |
| 562 | if its phdr mapping could not have supplied that. */ |
| 563 | if (mod->e_type == ET_EXEC) |
| 564 | { |
| 565 | if (ehdr.e_phoff - phdr->p_offset + phdr->p_vaddr != at_phdr) |
| 566 | return 0; |
| 567 | } |
| 568 | else |
| 569 | { |
| 570 | /* It could be a PIE. If the AT_PHDR value and our |
| 571 | phdr address don't match modulo ALIGN, then this |
| 572 | could not have been the right PIE. */ |
| 573 | if (((ehdr.e_phoff - phdr->p_offset + phdr->p_vaddr) & -align) |
| 574 | != (at_phdr & -align)) |
| 575 | return 0; |
| 576 | |
| 577 | /* Calculate the bias applied to the PIE's p_vaddr values. */ |
| 578 | GElf_Addr bias = (at_phdr - (ehdr.e_phoff - phdr->p_offset |
| 579 | + phdr->p_vaddr)); |
| 580 | |
| 581 | /* Final sanity check: if we have an AT_ENTRY value, |
| 582 | reject this PIE unless its biased e_entry matches. */ |
| 583 | if (at_entry != 0 && at_entry != ehdr.e_entry + bias) |
| 584 | return 0; |
| 585 | |
| 586 | /* If we're changing the module's address range, |
| 587 | we've just invalidated the module lookup table. */ |
Roland McGrath | 1743d7f | 2010-11-12 16:46:47 -0800 | [diff] [blame] | 588 | GElf_Addr mod_bias = dwfl_adjusted_address (mod, 0); |
| 589 | if (bias != mod_bias) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 590 | { |
Roland McGrath | 1743d7f | 2010-11-12 16:46:47 -0800 | [diff] [blame] | 591 | mod->low_addr -= mod_bias; |
| 592 | mod->high_addr -= mod_bias; |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 593 | mod->low_addr += bias; |
| 594 | mod->high_addr += bias; |
| 595 | |
| 596 | free (mod->dwfl->lookup_module); |
| 597 | mod->dwfl->lookup_module = NULL; |
| 598 | } |
| 599 | } |
| 600 | } |
| 601 | |
| 602 | if (phdr->p_type == PT_DYNAMIC) |
| 603 | { |
| 604 | Elf_Data *data = elf_getdata_rawchunk (mod->main.elf, phdr->p_offset, |
| 605 | phdr->p_filesz, ELF_T_DYN); |
| 606 | if (data == NULL) |
| 607 | continue; |
| 608 | const size_t entsize = gelf_fsize (mod->main.elf, |
| 609 | ELF_T_DYN, 1, EV_CURRENT); |
| 610 | const size_t n = data->d_size / entsize; |
| 611 | for (size_t j = 0; j < n; ++j) |
| 612 | { |
| 613 | GElf_Dyn dyn_mem; |
| 614 | GElf_Dyn *dyn = gelf_getdyn (data, j, &dyn_mem); |
| 615 | if (dyn != NULL && dyn->d_tag == DT_DEBUG) |
| 616 | { |
| 617 | d_val_vaddr = phdr->p_vaddr + entsize * j + entsize / 2; |
| 618 | break; |
| 619 | } |
| 620 | } |
| 621 | } |
| 622 | } |
| 623 | |
| 624 | if (d_val_vaddr != 0) |
| 625 | { |
| 626 | /* Now we have the final address from which to read &r_debug. */ |
Roland McGrath | 1743d7f | 2010-11-12 16:46:47 -0800 | [diff] [blame] | 627 | d_val_vaddr = dwfl_adjusted_address (mod, d_val_vaddr); |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 628 | |
| 629 | void *buffer = NULL; |
| 630 | size_t buffer_available = addrsize (ehdr.e_ident[EI_CLASS]); |
| 631 | |
Roland McGrath | 45c01cd | 2009-02-10 17:03:19 -0800 | [diff] [blame] | 632 | int segndx = INTUSE(dwfl_addrsegment) (mod->dwfl, d_val_vaddr, NULL); |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 633 | |
| 634 | if ((*memory_callback) (mod->dwfl, segndx, |
| 635 | &buffer, &buffer_available, |
| 636 | d_val_vaddr, buffer_available, |
| 637 | memory_callback_arg)) |
| 638 | { |
| 639 | const union |
| 640 | { |
| 641 | Elf32_Addr a32; |
| 642 | Elf64_Addr a64; |
| 643 | } *u = buffer; |
| 644 | |
| 645 | GElf_Addr vaddr; |
| 646 | if (ehdr.e_ident[EI_CLASS] == ELFCLASS32) |
| 647 | vaddr = (ehdr.e_ident[EI_DATA] == ELFDATA2MSB |
| 648 | ? BE32 (u->a32) : LE32 (u->a32)); |
| 649 | else |
| 650 | vaddr = (ehdr.e_ident[EI_DATA] == ELFDATA2MSB |
| 651 | ? BE64 (u->a64) : LE64 (u->a64)); |
| 652 | |
| 653 | (*memory_callback) (mod->dwfl, -1, &buffer, &buffer_available, 0, 0, |
| 654 | memory_callback_arg); |
| 655 | |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 656 | if (*elfclass == ELFCLASSNONE) |
| 657 | *elfclass = ehdr.e_ident[EI_CLASS]; |
| 658 | else if (*elfclass != ehdr.e_ident[EI_CLASS]) |
| 659 | return 0; |
| 660 | |
| 661 | if (*elfdata == ELFDATANONE) |
| 662 | *elfdata = ehdr.e_ident[EI_DATA]; |
| 663 | else if (*elfdata != ehdr.e_ident[EI_DATA]) |
| 664 | return 0; |
| 665 | |
| 666 | return vaddr; |
| 667 | } |
| 668 | } |
| 669 | |
| 670 | return 0; |
| 671 | } |
| 672 | |
| 673 | /* Try to find an existing executable module with a DT_DEBUG. */ |
| 674 | static GElf_Addr |
| 675 | find_executable (Dwfl *dwfl, GElf_Addr at_phdr, GElf_Addr at_entry, |
| 676 | uint_fast8_t *elfclass, uint_fast8_t *elfdata, |
| 677 | Dwfl_Memory_Callback *memory_callback, |
| 678 | void *memory_callback_arg) |
| 679 | { |
| 680 | for (Dwfl_Module *mod = dwfl->modulelist; mod != NULL; mod = mod->next) |
| 681 | if (mod->main.elf != NULL) |
| 682 | { |
| 683 | GElf_Addr r_debug_vaddr = consider_executable (mod, at_phdr, at_entry, |
| 684 | elfclass, elfdata, |
| 685 | memory_callback, |
| 686 | memory_callback_arg); |
| 687 | if (r_debug_vaddr != 0) |
| 688 | return r_debug_vaddr; |
| 689 | } |
| 690 | |
| 691 | return 0; |
| 692 | } |
| 693 | |
| 694 | |
| 695 | int |
| 696 | dwfl_link_map_report (Dwfl *dwfl, const void *auxv, size_t auxv_size, |
| 697 | Dwfl_Memory_Callback *memory_callback, |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 698 | void *memory_callback_arg, |
| 699 | struct r_debug_info *r_debug_info) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 700 | { |
| 701 | GElf_Addr r_debug_vaddr = 0; |
| 702 | |
| 703 | uint_fast8_t elfclass = ELFCLASSNONE; |
| 704 | uint_fast8_t elfdata = ELFDATANONE; |
| 705 | if (likely (auxv != NULL) |
| 706 | && likely (auxv_format_probe (auxv, auxv_size, &elfclass, &elfdata))) |
| 707 | { |
| 708 | GElf_Addr entry = 0; |
| 709 | GElf_Addr phdr = 0; |
| 710 | GElf_Xword phent = 0; |
| 711 | GElf_Xword phnum = 0; |
| 712 | |
Roland McGrath | 3999ce1 | 2013-01-07 14:53:37 -0800 | [diff] [blame] | 713 | #define READ_AUXV32(ptr) read_4ubyte_unaligned_noncvt (ptr) |
| 714 | #define READ_AUXV64(ptr) read_8ubyte_unaligned_noncvt (ptr) |
| 715 | #define AUXV_SCAN(NN, BL) do \ |
| 716 | { \ |
| 717 | const Elf##NN##_auxv_t *av = auxv; \ |
| 718 | for (size_t i = 0; i < auxv_size / sizeof av[0]; ++i) \ |
| 719 | { \ |
| 720 | uint##NN##_t type = READ_AUXV##NN (&av[i].a_type); \ |
| 721 | uint##NN##_t val = BL##NN (READ_AUXV##NN (&av[i].a_un.a_val)); \ |
| 722 | if (type == BL##NN (AT_ENTRY)) \ |
| 723 | entry = val; \ |
| 724 | else if (type == BL##NN (AT_PHDR)) \ |
| 725 | phdr = val; \ |
| 726 | else if (type == BL##NN (AT_PHNUM)) \ |
| 727 | phnum = val; \ |
| 728 | else if (type == BL##NN (AT_PHENT)) \ |
| 729 | phent = val; \ |
| 730 | else if (type == BL##NN (AT_PAGESZ)) \ |
| 731 | { \ |
| 732 | if (val > 1 \ |
| 733 | && (dwfl->segment_align == 0 \ |
| 734 | || val < dwfl->segment_align)) \ |
| 735 | dwfl->segment_align = val; \ |
| 736 | } \ |
| 737 | } \ |
| 738 | } \ |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 739 | while (0) |
| 740 | |
| 741 | if (elfclass == ELFCLASS32) |
| 742 | { |
| 743 | if (elfdata == ELFDATA2MSB) |
| 744 | AUXV_SCAN (32, BE); |
| 745 | else |
| 746 | AUXV_SCAN (32, LE); |
| 747 | } |
| 748 | else |
| 749 | { |
| 750 | if (elfdata == ELFDATA2MSB) |
| 751 | AUXV_SCAN (64, BE); |
| 752 | else |
| 753 | AUXV_SCAN (64, LE); |
| 754 | } |
| 755 | |
| 756 | /* If we found the phdr dimensions, search phdrs for PT_DYNAMIC. */ |
| 757 | GElf_Addr dyn_vaddr = 0; |
| 758 | GElf_Xword dyn_filesz = 0; |
Roland McGrath | d05c596 | 2010-05-04 18:05:22 -0700 | [diff] [blame] | 759 | GElf_Addr dyn_bias = (GElf_Addr) -1; |
| 760 | |
| 761 | inline bool consider_phdr (GElf_Word type, |
| 762 | GElf_Addr vaddr, GElf_Xword filesz) |
| 763 | { |
| 764 | switch (type) |
| 765 | { |
| 766 | case PT_PHDR: |
| 767 | if (dyn_bias == (GElf_Addr) -1 |
| 768 | /* Do a sanity check on the putative address. */ |
| 769 | && ((vaddr & (dwfl->segment_align - 1)) |
| 770 | == (phdr & (dwfl->segment_align - 1)))) |
| 771 | { |
| 772 | dyn_bias = phdr - vaddr; |
| 773 | return dyn_vaddr != 0; |
| 774 | } |
| 775 | break; |
| 776 | |
| 777 | case PT_DYNAMIC: |
| 778 | dyn_vaddr = vaddr; |
| 779 | dyn_filesz = filesz; |
| 780 | return dyn_bias != (GElf_Addr) -1; |
| 781 | } |
| 782 | |
| 783 | return false; |
| 784 | } |
| 785 | |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 786 | if (phdr != 0 && phnum != 0) |
| 787 | { |
| 788 | Dwfl_Module *phdr_mod; |
| 789 | int phdr_segndx = INTUSE(dwfl_addrsegment) (dwfl, phdr, &phdr_mod); |
| 790 | Elf_Data in = |
| 791 | { |
| 792 | .d_type = ELF_T_PHDR, |
| 793 | .d_version = EV_CURRENT, |
| 794 | .d_size = phnum * phent, |
| 795 | .d_buf = NULL |
| 796 | }; |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 797 | bool in_ok = (*memory_callback) (dwfl, phdr_segndx, &in.d_buf, |
| 798 | &in.d_size, phdr, phnum * phent, |
| 799 | memory_callback_arg); |
Mark Wielaard | 69d68dd | 2015-12-01 23:11:55 +0100 | [diff] [blame] | 800 | bool in_from_exec = false; |
Mark Wielaard | 355b408 | 2015-12-01 22:16:00 +0100 | [diff] [blame] | 801 | if (! in_ok |
| 802 | && dwfl->user_core != NULL |
| 803 | && dwfl->user_core->executable_for_core != NULL) |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 804 | { |
| 805 | /* AUXV -> PHDR -> DYNAMIC |
| 806 | Both AUXV and DYNAMIC should be always present in a core file. |
| 807 | PHDR may be missing in core file, try to read it from |
| 808 | EXECUTABLE_FOR_CORE to find where DYNAMIC is located in the |
| 809 | core file. */ |
| 810 | |
Mark Wielaard | 355b408 | 2015-12-01 22:16:00 +0100 | [diff] [blame] | 811 | int fd = open (dwfl->user_core->executable_for_core, O_RDONLY); |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 812 | Elf *elf; |
| 813 | Dwfl_Error error = DWFL_E_ERRNO; |
| 814 | if (fd != -1) |
| 815 | error = __libdw_open_file (&fd, &elf, true, false); |
| 816 | if (error != DWFL_E_NOERROR) |
| 817 | { |
| 818 | __libdwfl_seterrno (error); |
| 819 | return false; |
| 820 | } |
| 821 | GElf_Ehdr ehdr_mem, *ehdr = gelf_getehdr (elf, &ehdr_mem); |
| 822 | if (ehdr == NULL) |
| 823 | { |
| 824 | elf_end (elf); |
| 825 | close (fd); |
| 826 | __libdwfl_seterrno (DWFL_E_LIBELF); |
| 827 | return false; |
| 828 | } |
Mark Wielaard | 712c8fa | 2014-11-22 23:08:48 +0100 | [diff] [blame] | 829 | size_t e_phnum; |
| 830 | if (elf_getphdrnum (elf, &e_phnum) != 0) |
| 831 | { |
| 832 | elf_end (elf); |
| 833 | close (fd); |
| 834 | __libdwfl_seterrno (DWFL_E_LIBELF); |
| 835 | return false; |
| 836 | } |
| 837 | if (e_phnum != phnum || ehdr->e_phentsize != phent) |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 838 | { |
| 839 | elf_end (elf); |
| 840 | close (fd); |
| 841 | __libdwfl_seterrno (DWFL_E_BADELF); |
| 842 | return false; |
| 843 | } |
| 844 | off_t off = ehdr->e_phoff; |
| 845 | assert (in.d_buf == NULL); |
| 846 | assert (in.d_size == phnum * phent); |
| 847 | in.d_buf = malloc (in.d_size); |
| 848 | if (unlikely (in.d_buf == NULL)) |
| 849 | { |
| 850 | elf_end (elf); |
| 851 | close (fd); |
| 852 | __libdwfl_seterrno (DWFL_E_NOMEM); |
| 853 | return false; |
| 854 | } |
| 855 | ssize_t nread = pread_retry (fd, in.d_buf, in.d_size, off); |
| 856 | elf_end (elf); |
| 857 | close (fd); |
| 858 | if (nread != (ssize_t) in.d_size) |
| 859 | { |
| 860 | free (in.d_buf); |
| 861 | __libdwfl_seterrno (DWFL_E_ERRNO); |
| 862 | return false; |
| 863 | } |
| 864 | in_ok = true; |
Mark Wielaard | 69d68dd | 2015-12-01 23:11:55 +0100 | [diff] [blame] | 865 | in_from_exec = true; |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 866 | } |
| 867 | if (in_ok) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 868 | { |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 869 | if (unlikely (phnum > SIZE_MAX / phent)) |
| 870 | { |
| 871 | __libdwfl_seterrno (DWFL_E_NOMEM); |
| 872 | return false; |
| 873 | } |
| 874 | size_t nbytes = phnum * phent; |
| 875 | void *buf = malloc (nbytes); |
| 876 | Elf32_Phdr (*p32)[phnum] = buf; |
| 877 | Elf64_Phdr (*p64)[phnum] = buf; |
Mark Wielaard | f592035 | 2015-05-22 18:31:58 +0200 | [diff] [blame] | 878 | if (unlikely (buf == NULL)) |
| 879 | { |
| 880 | __libdwfl_seterrno (DWFL_E_NOMEM); |
| 881 | return false; |
| 882 | } |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 883 | Elf_Data out = |
| 884 | { |
| 885 | .d_type = ELF_T_PHDR, |
| 886 | .d_version = EV_CURRENT, |
| 887 | .d_size = phnum * phent, |
Mark Wielaard | f592035 | 2015-05-22 18:31:58 +0200 | [diff] [blame] | 888 | .d_buf = buf |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 889 | }; |
| 890 | in.d_size = out.d_size; |
| 891 | if (likely ((elfclass == ELFCLASS32 |
| 892 | ? elf32_xlatetom : elf64_xlatetom) |
| 893 | (&out, &in, elfdata) != NULL)) |
| 894 | { |
| 895 | /* We are looking for PT_DYNAMIC. */ |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 896 | if (elfclass == ELFCLASS32) |
| 897 | { |
| 898 | for (size_t i = 0; i < phnum; ++i) |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 899 | if (consider_phdr ((*p32)[i].p_type, |
| 900 | (*p32)[i].p_vaddr, |
| 901 | (*p32)[i].p_filesz)) |
Roland McGrath | d05c596 | 2010-05-04 18:05:22 -0700 | [diff] [blame] | 902 | break; |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 903 | } |
| 904 | else |
| 905 | { |
| 906 | for (size_t i = 0; i < phnum; ++i) |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 907 | if (consider_phdr ((*p64)[i].p_type, |
| 908 | (*p64)[i].p_vaddr, |
| 909 | (*p64)[i].p_filesz)) |
Roland McGrath | d05c596 | 2010-05-04 18:05:22 -0700 | [diff] [blame] | 910 | break; |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 911 | } |
| 912 | } |
| 913 | |
Mark Wielaard | 69d68dd | 2015-12-01 23:11:55 +0100 | [diff] [blame] | 914 | if (in_from_exec) |
| 915 | free (in.d_buf); |
| 916 | else |
| 917 | (*memory_callback) (dwfl, -1, &in.d_buf, &in.d_size, 0, 0, |
| 918 | memory_callback_arg); |
Mark Wielaard | f592035 | 2015-05-22 18:31:58 +0200 | [diff] [blame] | 919 | free (buf); |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 920 | } |
| 921 | else |
| 922 | /* We could not read the executable's phdrs from the |
| 923 | memory image. If we have a presupplied executable, |
| 924 | we can still use the AT_PHDR and AT_ENTRY values to |
| 925 | verify it, and to adjust its bias if it's a PIE. |
| 926 | |
| 927 | If there was an ET_EXEC module presupplied that contains |
| 928 | the AT_PHDR address, then we only consider that one. |
| 929 | We'll either accept it if its phdr location and e_entry |
| 930 | make sense or reject it if they don't. If there is no |
| 931 | presupplied ET_EXEC, then look for a presupplied module, |
| 932 | which might be a PIE (ET_DYN) that needs its bias adjusted. */ |
| 933 | r_debug_vaddr = ((phdr_mod == NULL |
| 934 | || phdr_mod->main.elf == NULL |
| 935 | || phdr_mod->e_type != ET_EXEC) |
| 936 | ? find_executable (dwfl, phdr, entry, |
| 937 | &elfclass, &elfdata, |
| 938 | memory_callback, |
| 939 | memory_callback_arg) |
| 940 | : consider_executable (phdr_mod, phdr, entry, |
| 941 | &elfclass, &elfdata, |
| 942 | memory_callback, |
| 943 | memory_callback_arg)); |
| 944 | } |
| 945 | |
| 946 | /* If we found PT_DYNAMIC, search it for DT_DEBUG. */ |
| 947 | if (dyn_filesz != 0) |
| 948 | { |
Roland McGrath | d05c596 | 2010-05-04 18:05:22 -0700 | [diff] [blame] | 949 | if (dyn_bias != (GElf_Addr) -1) |
| 950 | dyn_vaddr += dyn_bias; |
| 951 | |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 952 | Elf_Data in = |
| 953 | { |
| 954 | .d_type = ELF_T_DYN, |
| 955 | .d_version = EV_CURRENT, |
| 956 | .d_size = dyn_filesz, |
| 957 | .d_buf = NULL |
| 958 | }; |
| 959 | int dyn_segndx = dwfl_addrsegment (dwfl, dyn_vaddr, NULL); |
| 960 | if ((*memory_callback) (dwfl, dyn_segndx, &in.d_buf, &in.d_size, |
| 961 | dyn_vaddr, dyn_filesz, memory_callback_arg)) |
| 962 | { |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 963 | void *buf = malloc (dyn_filesz); |
| 964 | Elf32_Dyn (*d32)[dyn_filesz / sizeof (Elf32_Dyn)] = buf; |
| 965 | Elf64_Dyn (*d64)[dyn_filesz / sizeof (Elf64_Dyn)] = buf; |
Mark Wielaard | f592035 | 2015-05-22 18:31:58 +0200 | [diff] [blame] | 966 | if (unlikely (buf == NULL)) |
| 967 | { |
| 968 | __libdwfl_seterrno (DWFL_E_NOMEM); |
| 969 | return false; |
| 970 | } |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 971 | Elf_Data out = |
| 972 | { |
| 973 | .d_type = ELF_T_DYN, |
| 974 | .d_version = EV_CURRENT, |
| 975 | .d_size = dyn_filesz, |
Mark Wielaard | f592035 | 2015-05-22 18:31:58 +0200 | [diff] [blame] | 976 | .d_buf = buf |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 977 | }; |
| 978 | in.d_size = out.d_size; |
| 979 | if (likely ((elfclass == ELFCLASS32 |
| 980 | ? elf32_xlatetom : elf64_xlatetom) |
| 981 | (&out, &in, elfdata) != NULL)) |
| 982 | { |
Roland McGrath | be13930 | 2010-04-14 12:54:45 -0700 | [diff] [blame] | 983 | /* We are looking for DT_DEBUG. */ |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 984 | if (elfclass == ELFCLASS32) |
| 985 | { |
| 986 | size_t n = dyn_filesz / sizeof (Elf32_Dyn); |
| 987 | for (size_t i = 0; i < n; ++i) |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 988 | if ((*d32)[i].d_tag == DT_DEBUG) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 989 | { |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 990 | r_debug_vaddr = (*d32)[i].d_un.d_val; |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 991 | break; |
| 992 | } |
| 993 | } |
| 994 | else |
| 995 | { |
| 996 | size_t n = dyn_filesz / sizeof (Elf64_Dyn); |
| 997 | for (size_t i = 0; i < n; ++i) |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 998 | if ((*d64)[i].d_tag == DT_DEBUG) |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 999 | { |
Chih-Hung Hsieh | 7eff36d | 2015-10-06 15:53:15 -0700 | [diff] [blame] | 1000 | r_debug_vaddr = (*d64)[i].d_un.d_val; |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 1001 | break; |
| 1002 | } |
| 1003 | } |
| 1004 | } |
| 1005 | |
| 1006 | (*memory_callback) (dwfl, -1, &in.d_buf, &in.d_size, 0, 0, |
| 1007 | memory_callback_arg); |
Mark Wielaard | f592035 | 2015-05-22 18:31:58 +0200 | [diff] [blame] | 1008 | free (buf); |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 1009 | } |
| 1010 | } |
| 1011 | } |
| 1012 | else |
| 1013 | /* We have to look for a presupplied executable file to determine |
| 1014 | the vaddr of its dynamic section and DT_DEBUG therein. */ |
| 1015 | r_debug_vaddr = find_executable (dwfl, 0, 0, &elfclass, &elfdata, |
| 1016 | memory_callback, memory_callback_arg); |
| 1017 | |
| 1018 | if (r_debug_vaddr == 0) |
| 1019 | return 0; |
| 1020 | |
| 1021 | /* For following pointers from struct link_map, we will use an |
| 1022 | integrated memory access callback that can consult module text |
| 1023 | elided from the core file. This is necessary when the l_name |
| 1024 | pointer for the dynamic linker's own entry is a pointer into the |
| 1025 | executable's .interp section. */ |
| 1026 | struct integrated_memory_callback mcb = |
| 1027 | { |
| 1028 | .memory_callback = memory_callback, |
| 1029 | .memory_callback_arg = memory_callback_arg |
| 1030 | }; |
| 1031 | |
| 1032 | /* Now we can follow the dynamic linker's library list. */ |
| 1033 | return report_r_debug (elfclass, elfdata, dwfl, r_debug_vaddr, |
Jan Kratochvil | 8ff8629 | 2013-05-30 13:21:20 +0200 | [diff] [blame] | 1034 | &integrated_memory_callback, &mcb, r_debug_info); |
Roland McGrath | b4d6f0f | 2008-08-25 22:55:17 +0000 | [diff] [blame] | 1035 | } |
| 1036 | INTDEF (dwfl_link_map_report) |