tools/objtool/elf.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * elf.c - ELF access library
   4  *
   5  * Adapted from kpatch (https://github.com/dynup/kpatch):
   6  * Copyright (C) 2013-2015 Josh Poimboeuf <jpoimboe@redhat.com>
   7  * Copyright (C) 2014 Seth Jennings <sjenning@redhat.com>
   8  */
   9
  10 #include <sys/types.h>
  11 #include <sys/stat.h>
  12 #include <sys/mman.h>
  13 #include <fcntl.h>
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include <unistd.h>
  18 #include <errno.h>
  19 #include <linux/interval_tree_generic.h>
  20 #include <objtool/builtin.h>
  21
  22 #include <objtool/elf.h>
  23 #include <objtool/warn.h>
  24
  25 #define MAX_NAME_LEN 128
  26
  27 static inline u32 str_hash(const char *str)
  28 {
  29         return jhash(str, strlen(str), 0);
  30 }
  31
  32 #define __elf_table(name)       (elf->name##_hash)
  33 #define __elf_bits(name)        (elf->name##_bits)
  34
  35 #define elf_hash_add(name, node, key) \
  36         hlist_add_head(node, &__elf_table(name)[hash_min(key, __elf_bits(name))])
  37
  38 #define elf_hash_for_each_possible(name, obj, member, key) \
  39         hlist_for_each_entry(obj, &__elf_table(name)[hash_min(key, __elf_bits(name))], member)
  40
  41 #define elf_alloc_hash(name, size) \
  42 ({ \
  43         __elf_bits(name) = max(10, ilog2(size)); \
  44         __elf_table(name) = mmap(NULL, sizeof(struct hlist_head) << __elf_bits(name), \
  45                                  PROT_READ|PROT_WRITE, \
  46                                  MAP_PRIVATE|MAP_ANON, -1, 0); \
  47         if (__elf_table(name) == (void *)-1L) { \
  48                 WARN("mmap fail " #name); \
  49                 __elf_table(name) = NULL; \
  50         } \
  51         __elf_table(name); \
  52 })
  53
  54 static inline unsigned long __sym_start(struct symbol *s)
  55 {
  56         return s->offset;
  57 }
  58
  59 static inline unsigned long __sym_last(struct symbol *s)
  60 {
  61         return s->offset + s->len - 1;
  62 }
  63
  64 INTERVAL_TREE_DEFINE(struct symbol, node, unsigned long, __subtree_last,
  65                      __sym_start, __sym_last, static, __sym)
  66
  67 #define __sym_for_each(_iter, _tree, _start, _end)                      \
  68         for (_iter = __sym_iter_first((_tree), (_start), (_end));       \
  69              _iter; _iter = __sym_iter_next(_iter, (_start), (_end)))
  70
  71 struct symbol_hole {
  72         unsigned long key;
  73         const struct symbol *sym;
  74 };
  75
  76 /*
  77  * Find !section symbol where @offset is after it.
  78  */
  79 static int symbol_hole_by_offset(const void *key, const struct rb_node *node)
  80 {
  81         const struct symbol *s = rb_entry(node, struct symbol, node);
  82         struct symbol_hole *sh = (void *)key;
  83
  84         if (sh->key < s->offset)
  85                 return -1;
  86
  87         if (sh->key >= s->offset + s->len) {
  88                 if (s->type != STT_SECTION)
  89                         sh->sym = s;
  90                 return 1;
  91         }
  92
  93         return 0;
  94 }
  95
  96 struct section *find_section_by_name(const struct elf *elf, const char *name)
  97 {
  98         struct section *sec;
  99
 100         elf_hash_for_each_possible(section_name, sec, name_hash, str_hash(name)) {
 101                 if (!strcmp(sec->name, name))
 102                         return sec;
 103         }
 104
 105         return NULL;
 106 }
 107
 108 static struct section *find_section_by_index(struct elf *elf,
 109                                              unsigned int idx)
 110 {
 111         struct section *sec;
 112
 113         elf_hash_for_each_possible(section, sec, hash, idx) {
 114                 if (sec->idx == idx)
 115                         return sec;
 116         }
 117
 118         return NULL;
 119 }
 120
 121 static struct symbol *find_symbol_by_index(struct elf *elf, unsigned int idx)
 122 {
 123         struct symbol *sym;
 124
 125         elf_hash_for_each_possible(symbol, sym, hash, idx) {
 126                 if (sym->idx == idx)
 127                         return sym;
 128         }
 129
 130         return NULL;
 131 }
 132
 133 struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset)
 134 {
 135         struct rb_root_cached *tree = (struct rb_root_cached *)&sec->symbol_tree;
 136         struct symbol *iter;
 137
 138         __sym_for_each(iter, tree, offset, offset) {
 139                 if (iter->offset == offset && iter->type != STT_SECTION)
 140                         return iter;
 141         }
 142
 143         return NULL;
 144 }
 145
 146 struct symbol *find_func_by_offset(struct section *sec, unsigned long offset)
 147 {
 148         struct rb_root_cached *tree = (struct rb_root_cached *)&sec->symbol_tree;
 149         struct symbol *iter;
 150
 151         __sym_for_each(iter, tree, offset, offset) {
 152                 if (iter->offset == offset && iter->type == STT_FUNC)
 153                         return iter;
 154         }
 155
 156         return NULL;
 157 }
 158
 159 struct symbol *find_symbol_containing(const struct section *sec, unsigned long offset)
 160 {
 161         struct rb_root_cached *tree = (struct rb_root_cached *)&sec->symbol_tree;
 162         struct symbol *iter;
 163
 164         __sym_for_each(iter, tree, offset, offset) {
 165                 if (iter->type != STT_SECTION)
 166                         return iter;
 167         }
 168
 169         return NULL;
 170 }
 171
 172 /*
 173  * Returns size of hole starting at @offset.
 174  */
 175 int find_symbol_hole_containing(const struct section *sec, unsigned long offset)
 176 {
 177         struct symbol_hole hole = {
 178                 .key = offset,
 179                 .sym = NULL,
 180         };
 181         struct rb_node *n;
 182         struct symbol *s;
 183
 184         /*
 185          * Find the rightmost symbol for which @offset is after it.
 186          */
 187         n = rb_find(&hole, &sec->symbol_tree.rb_root, symbol_hole_by_offset);
 188
 189         /* found a symbol that contains @offset */
 190         if (n)
 191                 return 0; /* not a hole */
 192
 193         /* didn't find a symbol for which @offset is after it */
 194         if (!hole.sym)
 195                 return 0; /* not a hole */
 196
 197         /* @offset >= sym->offset + sym->len, find symbol after it */
 198         n = rb_next(&hole.sym->node);
 199         if (!n)
 200                 return -1; /* until end of address space */
 201
 202         /* hole until start of next symbol */
 203         s = rb_entry(n, struct symbol, node);
 204         return s->offset - offset;
 205 }
 206
 207 struct symbol *find_func_containing(struct section *sec, unsigned long offset)
 208 {
 209         struct rb_root_cached *tree = (struct rb_root_cached *)&sec->symbol_tree;
 210         struct symbol *iter;
 211
 212         __sym_for_each(iter, tree, offset, offset) {
 213                 if (iter->type == STT_FUNC)
 214                         return iter;
 215         }
 216
 217         return NULL;
 218 }
 219
 220 struct symbol *find_symbol_by_name(const struct elf *elf, const char *name)
 221 {
 222         struct symbol *sym;
 223
 224         elf_hash_for_each_possible(symbol_name, sym, name_hash, str_hash(name)) {
 225                 if (!strcmp(sym->name, name))
 226                         return sym;
 227         }
 228
 229         return NULL;
 230 }
 231
 232 struct reloc *find_reloc_by_dest_range(const struct elf *elf, struct section *sec,
 233                                      unsigned long offset, unsigned int len)
 234 {
 235         struct reloc *reloc, *r = NULL;
 236         unsigned long o;
 237
 238         if (!sec->reloc)
 239                 return NULL;
 240
 241         sec = sec->reloc;
 242
 243         for_offset_range(o, offset, offset + len) {
 244                 elf_hash_for_each_possible(reloc, reloc, hash,
 245                                            sec_offset_hash(sec, o)) {
 246                         if (reloc->sec != sec)
 247                                 continue;
 248
 249                         if (reloc->offset >= offset && reloc->offset < offset + len) {
 250                                 if (!r || reloc->offset < r->offset)
 251                                         r = reloc;
 252                         }
 253                 }
 254                 if (r)
 255                         return r;
 256         }
 257
 258         return NULL;
 259 }
 260
 261 struct reloc *find_reloc_by_dest(const struct elf *elf, struct section *sec, unsigned long offset)
 262 {
 263         return find_reloc_by_dest_range(elf, sec, offset, 1);
 264 }
 265
 266 static int read_sections(struct elf *elf)
 267 {
 268         Elf_Scn *s = NULL;
 269         struct section *sec;
 270         size_t shstrndx, sections_nr;
 271         int i;
 272
 273         if (elf_getshdrnum(elf->elf, &sections_nr)) {
 274                 WARN_ELF("elf_getshdrnum");
 275                 return -1;
 276         }
 277
 278         if (elf_getshdrstrndx(elf->elf, &shstrndx)) {
 279                 WARN_ELF("elf_getshdrstrndx");
 280                 return -1;
 281         }
 282
 283         if (!elf_alloc_hash(section, sections_nr) ||
 284             !elf_alloc_hash(section_name, sections_nr))
 285                 return -1;
 286
 287         elf->section_data = calloc(sections_nr, sizeof(*sec));
 288         if (!elf->section_data) {
 289                 perror("calloc");
 290                 return -1;
 291         }
 292         for (i = 0; i < sections_nr; i++) {
 293                 sec = &elf->section_data[i];
 294
 295                 INIT_LIST_HEAD(&sec->symbol_list);
 296                 INIT_LIST_HEAD(&sec->reloc_list);
 297
 298                 s = elf_getscn(elf->elf, i);
 299                 if (!s) {
 300                         WARN_ELF("elf_getscn");
 301                         return -1;
 302                 }
 303
 304                 sec->idx = elf_ndxscn(s);
 305
 306                 if (!gelf_getshdr(s, &sec->sh)) {
 307                         WARN_ELF("gelf_getshdr");
 308                         return -1;
 309                 }
 310
 311                 sec->name = elf_strptr(elf->elf, shstrndx, sec->sh.sh_name);
 312                 if (!sec->name) {
 313                         WARN_ELF("elf_strptr");
 314                         return -1;
 315                 }
 316
 317                 if (sec->sh.sh_size != 0) {
 318                         sec->data = elf_getdata(s, NULL);
 319                         if (!sec->data) {
 320                                 WARN_ELF("elf_getdata");
 321                                 return -1;
 322                         }
 323                         if (sec->data->d_off != 0 ||
 324                             sec->data->d_size != sec->sh.sh_size) {
 325                                 WARN("unexpected data attributes for %s",
 326                                      sec->name);
 327                                 return -1;
 328                         }
 329                 }
 330
 331                 if (sec->sh.sh_flags & SHF_EXECINSTR)
 332                         elf->text_size += sec->sh.sh_size;
 333
 334                 list_add_tail(&sec->list, &elf->sections);
 335                 elf_hash_add(section, &sec->hash, sec->idx);
 336                 elf_hash_add(section_name, &sec->name_hash, str_hash(sec->name));
 337         }
 338
 339         if (opts.stats) {
 340                 printf("nr_sections: %lu\n", (unsigned long)sections_nr);
 341                 printf("section_bits: %d\n", elf->section_bits);
 342         }
 343
 344         /* sanity check, one more call to elf_nextscn() should return NULL */
 345         if (elf_nextscn(elf->elf, s)) {
 346                 WARN("section entry mismatch");
 347                 return -1;
 348         }
 349
 350         return 0;
 351 }
 352
 353 static void elf_add_symbol(struct elf *elf, struct symbol *sym)
 354 {
 355         struct list_head *entry;
 356         struct rb_node *pnode;
 357         struct symbol *iter;
 358
 359         INIT_LIST_HEAD(&sym->reloc_list);
 360         INIT_LIST_HEAD(&sym->pv_target);
 361         sym->alias = sym;
 362
 363         sym->type = GELF_ST_TYPE(sym->sym.st_info);
 364         sym->bind = GELF_ST_BIND(sym->sym.st_info);
 365
 366         if (sym->type == STT_FILE)
 367                 elf->num_files++;
 368
 369         sym->offset = sym->sym.st_value;
 370         sym->len = sym->sym.st_size;
 371
 372         __sym_for_each(iter, &sym->sec->symbol_tree, sym->offset, sym->offset) {
 373                 if (iter->offset == sym->offset && iter->type == sym->type)
 374                         iter->alias = sym;
 375         }
 376
 377         __sym_insert(sym, &sym->sec->symbol_tree);
 378         pnode = rb_prev(&sym->node);
 379         if (pnode)
 380                 entry = &rb_entry(pnode, struct symbol, node)->list;
 381         else
 382                 entry = &sym->sec->symbol_list;
 383         list_add(&sym->list, entry);
 384         elf_hash_add(symbol, &sym->hash, sym->idx);
 385         elf_hash_add(symbol_name, &sym->name_hash, str_hash(sym->name));
 386
 387         /*
 388          * Don't store empty STT_NOTYPE symbols in the rbtree.  They
 389          * can exist within a function, confusing the sorting.
 390          */
 391         if (!sym->len)
 392                 __sym_remove(sym, &sym->sec->symbol_tree);
 393 }
 394
 395 static int read_symbols(struct elf *elf)
 396 {
 397         struct section *symtab, *symtab_shndx, *sec;
 398         struct symbol *sym, *pfunc;
 399         int symbols_nr, i;
 400         char *coldstr;
 401         Elf_Data *shndx_data = NULL;
 402         Elf32_Word shndx;
 403
 404         symtab = find_section_by_name(elf, ".symtab");
 405         if (symtab) {
 406                 symtab_shndx = find_section_by_name(elf, ".symtab_shndx");
 407                 if (symtab_shndx)
 408                         shndx_data = symtab_shndx->data;
 409
 410                 symbols_nr = symtab->sh.sh_size / symtab->sh.sh_entsize;
 411         } else {
 412                 /*
 413                  * A missing symbol table is actually possible if it's an empty
 414                  * .o file. This can happen for thunk_64.o. Make sure to at
 415                  * least allocate the symbol hash tables so we can do symbol
 416                  * lookups without crashing.
 417                  */
 418                 symbols_nr = 0;
 419         }
 420
 421         if (!elf_alloc_hash(symbol, symbols_nr) ||
 422             !elf_alloc_hash(symbol_name, symbols_nr))
 423                 return -1;
 424
 425         elf->symbol_data = calloc(symbols_nr, sizeof(*sym));
 426         if (!elf->symbol_data) {
 427                 perror("calloc");
 428                 return -1;
 429         }
 430         for (i = 0; i < symbols_nr; i++) {
 431                 sym = &elf->symbol_data[i];
 432
 433                 sym->idx = i;
 434
 435                 if (!gelf_getsymshndx(symtab->data, shndx_data, i, &sym->sym,
 436                                       &shndx)) {
 437                         WARN_ELF("gelf_getsymshndx");
 438                         goto err;
 439                 }
 440
 441                 sym->name = elf_strptr(elf->elf, symtab->sh.sh_link,
 442                                        sym->sym.st_name);
 443                 if (!sym->name) {
 444                         WARN_ELF("elf_strptr");
 445                         goto err;
 446                 }
 447
 448                 if ((sym->sym.st_shndx > SHN_UNDEF &&
 449                      sym->sym.st_shndx < SHN_LORESERVE) ||
 450                     (shndx_data && sym->sym.st_shndx == SHN_XINDEX)) {
 451                         if (sym->sym.st_shndx != SHN_XINDEX)
 452                                 shndx = sym->sym.st_shndx;
 453
 454                         sym->sec = find_section_by_index(elf, shndx);
 455                         if (!sym->sec) {
 456                                 WARN("couldn't find section for symbol %s",
 457                                      sym->name);
 458                                 goto err;
 459                         }
 460                         if (GELF_ST_TYPE(sym->sym.st_info) == STT_SECTION) {
 461                                 sym->name = sym->sec->name;
 462                                 sym->sec->sym = sym;
 463                         }
 464                 } else
 465                         sym->sec = find_section_by_index(elf, 0);
 466
 467                 elf_add_symbol(elf, sym);
 468         }
 469
 470         if (opts.stats) {
 471                 printf("nr_symbols: %lu\n", (unsigned long)symbols_nr);
 472                 printf("symbol_bits: %d\n", elf->symbol_bits);
 473         }
 474
 475         /* Create parent/child links for any cold subfunctions */
 476         list_for_each_entry(sec, &elf->sections, list) {
 477                 sec_for_each_sym(sec, sym) {
 478                         char pname[MAX_NAME_LEN + 1];
 479                         size_t pnamelen;
 480                         if (sym->type != STT_FUNC)
 481                                 continue;
 482
 483                         if (sym->pfunc == NULL)
 484                                 sym->pfunc = sym;
 485
 486                         if (sym->cfunc == NULL)
 487                                 sym->cfunc = sym;
 488
 489                         coldstr = strstr(sym->name, ".cold");
 490                         if (!coldstr)
 491                                 continue;
 492
 493                         pnamelen = coldstr - sym->name;
 494                         if (pnamelen > MAX_NAME_LEN) {
 495                                 WARN("%s(): parent function name exceeds maximum length of %d characters",
 496                                      sym->name, MAX_NAME_LEN);
 497                                 return -1;
 498                         }
 499
 500                         strncpy(pname, sym->name, pnamelen);
 501                         pname[pnamelen] = '\0';
 502                         pfunc = find_symbol_by_name(elf, pname);
 503
 504                         if (!pfunc) {
 505                                 WARN("%s(): can't find parent function",
 506                                      sym->name);
 507                                 return -1;
 508                         }
 509
 510                         sym->pfunc = pfunc;
 511                         pfunc->cfunc = sym;
 512
 513                         /*
 514                          * Unfortunately, -fnoreorder-functions puts the child
 515                          * inside the parent.  Remove the overlap so we can
 516                          * have sane assumptions.
 517                          *
 518                          * Note that pfunc->len now no longer matches
 519                          * pfunc->sym.st_size.
 520                          */
 521                         if (sym->sec == pfunc->sec &&
 522                             sym->offset >= pfunc->offset &&
 523                             sym->offset + sym->len == pfunc->offset + pfunc->len) {
 524                                 pfunc->len -= sym->len;
 525                         }
 526                 }
 527         }
 528
 529         return 0;
 530
 531 err:
 532         free(sym);
 533         return -1;
 534 }
 535
 536 static struct section *elf_create_reloc_section(struct elf *elf,
 537                                                 struct section *base,
 538                                                 int reltype);
 539
 540 int elf_add_reloc(struct elf *elf, struct section *sec, unsigned long offset,
 541                   unsigned int type, struct symbol *sym, s64 addend)
 542 {
 543         struct reloc *reloc;
 544
 545         if (!sec->reloc && !elf_create_reloc_section(elf, sec, SHT_RELA))
 546                 return -1;
 547
 548         reloc = malloc(sizeof(*reloc));
 549         if (!reloc) {
 550                 perror("malloc");
 551                 return -1;
 552         }
 553         memset(reloc, 0, sizeof(*reloc));
 554
 555         reloc->sec = sec->reloc;
 556         reloc->offset = offset;
 557         reloc->type = type;
 558         reloc->sym = sym;
 559         reloc->addend = addend;
 560
 561         list_add_tail(&reloc->sym_reloc_entry, &sym->reloc_list);
 562         list_add_tail(&reloc->list, &sec->reloc->reloc_list);
 563         elf_hash_add(reloc, &reloc->hash, reloc_hash(reloc));
 564
 565         sec->reloc->sh.sh_size += sec->reloc->sh.sh_entsize;
 566         sec->reloc->changed = true;
 567
 568         return 0;
 569 }
 570
 571 /*
 572  * Ensure that any reloc section containing references to @sym is marked
 573  * changed such that it will get re-generated in elf_rebuild_reloc_sections()
 574  * with the new symbol index.
 575  */
 576 static void elf_dirty_reloc_sym(struct elf *elf, struct symbol *sym)
 577 {
 578         struct reloc *reloc;
 579
 580         list_for_each_entry(reloc, &sym->reloc_list, sym_reloc_entry)
 581                 reloc->sec->changed = true;
 582 }
 583
 584 /*
 585  * The libelf API is terrible; gelf_update_sym*() takes a data block relative
 586  * index value, *NOT* the symbol index. As such, iterate the data blocks and
 587  * adjust index until it fits.
 588  *
 589  * If no data block is found, allow adding a new data block provided the index
 590  * is only one past the end.
 591  */
 592 static int elf_update_symbol(struct elf *elf, struct section *symtab,
 593                              struct section *symtab_shndx, struct symbol *sym)
 594 {
 595         Elf32_Word shndx = sym->sec ? sym->sec->idx : SHN_UNDEF;
 596         Elf_Data *symtab_data = NULL, *shndx_data = NULL;
 597         Elf64_Xword entsize = symtab->sh.sh_entsize;
 598         int max_idx, idx = sym->idx;
 599         Elf_Scn *s, *t = NULL;
 600         bool is_special_shndx = sym->sym.st_shndx >= SHN_LORESERVE &&
 601                                 sym->sym.st_shndx != SHN_XINDEX;
 602
 603         if (is_special_shndx)
 604                 shndx = sym->sym.st_shndx;
 605
 606         s = elf_getscn(elf->elf, symtab->idx);
 607         if (!s) {
 608                 WARN_ELF("elf_getscn");
 609                 return -1;
 610         }
 611
 612         if (symtab_shndx) {
 613                 t = elf_getscn(elf->elf, symtab_shndx->idx);
 614                 if (!t) {
 615                         WARN_ELF("elf_getscn");
 616                         return -1;
 617                 }
 618         }
 619
 620         for (;;) {
 621                 /* get next data descriptor for the relevant sections */
 622                 symtab_data = elf_getdata(s, symtab_data);
 623                 if (t)
 624                         shndx_data = elf_getdata(t, shndx_data);
 625
 626                 /* end-of-list */
 627                 if (!symtab_data) {
 628                         /*
 629                          * Over-allocate to avoid O(n^2) symbol creation
 630                          * behaviour.  The down side is that libelf doesn't
 631                          * like this; see elf_truncate_section() for the fixup.
 632                          */
 633                         int num = max(1U, sym->idx/3);
 634                         void *buf;
 635
 636                         if (idx) {
 637                                 /* we don't do holes in symbol tables */
 638                                 WARN("index out of range");
 639                                 return -1;
 640                         }
 641
 642                         /* if @idx == 0, it's the next contiguous entry, create it */
 643                         symtab_data = elf_newdata(s);
 644                         if (t)
 645                                 shndx_data = elf_newdata(t);
 646
 647                         buf = calloc(num, entsize);
 648                         if (!buf) {
 649                                 WARN("malloc");
 650                                 return -1;
 651                         }
 652
 653                         symtab_data->d_buf = buf;
 654                         symtab_data->d_size = num * entsize;
 655                         symtab_data->d_align = 1;
 656                         symtab_data->d_type = ELF_T_SYM;
 657
 658                         symtab->changed = true;
 659                         symtab->truncate = true;
 660
 661                         if (t) {
 662                                 buf = calloc(num, sizeof(Elf32_Word));
 663                                 if (!buf) {
 664                                         WARN("malloc");
 665                                         return -1;
 666                                 }
 667
 668                                 shndx_data->d_buf = buf;
 669                                 shndx_data->d_size = num * sizeof(Elf32_Word);
 670                                 shndx_data->d_align = sizeof(Elf32_Word);
 671                                 shndx_data->d_type = ELF_T_WORD;
 672
 673                                 symtab_shndx->changed = true;
 674                                 symtab_shndx->truncate = true;
 675                         }
 676
 677                         break;
 678                 }
 679
 680                 /* empty blocks should not happen */
 681                 if (!symtab_data->d_size) {
 682                         WARN("zero size data");
 683                         return -1;
 684                 }
 685
 686                 /* is this the right block? */
 687                 max_idx = symtab_data->d_size / entsize;
 688                 if (idx < max_idx)
 689                         break;
 690
 691                 /* adjust index and try again */
 692                 idx -= max_idx;
 693         }
 694
 695         /* something went side-ways */
 696         if (idx < 0) {
 697                 WARN("negative index");
 698                 return -1;
 699         }
 700
 701         /* setup extended section index magic and write the symbol */
 702         if ((shndx >= SHN_UNDEF && shndx < SHN_LORESERVE) || is_special_shndx) {
 703                 sym->sym.st_shndx = shndx;
 704                 if (!shndx_data)
 705                         shndx = 0;
 706         } else {
 707                 sym->sym.st_shndx = SHN_XINDEX;
 708                 if (!shndx_data) {
 709                         WARN("no .symtab_shndx");
 710                         return -1;
 711                 }
 712         }
 713
 714         if (!gelf_update_symshndx(symtab_data, shndx_data, idx, &sym->sym, shndx)) {
 715                 WARN_ELF("gelf_update_symshndx");
 716                 return -1;
 717         }
 718
 719         return 0;
 720 }
 721
 722 static struct symbol *
 723 __elf_create_symbol(struct elf *elf, struct symbol *sym)
 724 {
 725         struct section *symtab, *symtab_shndx;
 726         Elf32_Word first_non_local, new_idx;
 727         struct symbol *old;
 728
 729         symtab = find_section_by_name(elf, ".symtab");
 730         if (symtab) {
 731                 symtab_shndx = find_section_by_name(elf, ".symtab_shndx");
 732         } else {
 733                 WARN("no .symtab");
 734                 return NULL;
 735         }
 736
 737         new_idx = symtab->sh.sh_size / symtab->sh.sh_entsize;
 738
 739         if (GELF_ST_BIND(sym->sym.st_info) != STB_LOCAL)
 740                 goto non_local;
 741
 742         /*
 743          * Move the first global symbol, as per sh_info, into a new, higher
 744          * symbol index. This fees up a spot for a new local symbol.
 745          */
 746         first_non_local = symtab->sh.sh_info;
 747         old = find_symbol_by_index(elf, first_non_local);
 748         if (old) {
 749                 old->idx = new_idx;
 750
 751                 hlist_del(&old->hash);
 752                 elf_hash_add(symbol, &old->hash, old->idx);
 753
 754                 elf_dirty_reloc_sym(elf, old);
 755
 756                 if (elf_update_symbol(elf, symtab, symtab_shndx, old)) {
 757                         WARN("elf_update_symbol move");
 758                         return NULL;
 759                 }
 760
 761                 new_idx = first_non_local;
 762         }
 763
 764         /*
 765          * Either way, we will add a LOCAL symbol.
 766          */
 767         symtab->sh.sh_info += 1;
 768
 769 non_local:
 770         sym->idx = new_idx;
 771         if (elf_update_symbol(elf, symtab, symtab_shndx, sym)) {
 772                 WARN("elf_update_symbol");
 773                 return NULL;
 774         }
 775
 776         symtab->sh.sh_size += symtab->sh.sh_entsize;
 777         symtab->changed = true;
 778
 779         if (symtab_shndx) {
 780                 symtab_shndx->sh.sh_size += sizeof(Elf32_Word);
 781                 symtab_shndx->changed = true;
 782         }
 783
 784         return sym;
 785 }
 786
 787 static struct symbol *
 788 elf_create_section_symbol(struct elf *elf, struct section *sec)
 789 {
 790         struct symbol *sym = calloc(1, sizeof(*sym));
 791
 792         if (!sym) {
 793                 perror("malloc");
 794                 return NULL;
 795         }
 796
 797         sym->name = sec->name;
 798         sym->sec = sec;
 799
 800         // st_name 0
 801         sym->sym.st_info = GELF_ST_INFO(STB_LOCAL, STT_SECTION);
 802         // st_other 0
 803         // st_value 0
 804         // st_size 0
 805
 806         sym = __elf_create_symbol(elf, sym);
 807         if (sym)
 808                 elf_add_symbol(elf, sym);
 809
 810         return sym;
 811 }
 812
 813 static int elf_add_string(struct elf *elf, struct section *strtab, char *str);
 814
 815 struct symbol *
 816 elf_create_prefix_symbol(struct elf *elf, struct symbol *orig, long size)
 817 {
 818         struct symbol *sym = calloc(1, sizeof(*sym));
 819         size_t namelen = strlen(orig->name) + sizeof("__pfx_");
 820         char *name = malloc(namelen);
 821
 822         if (!sym || !name) {
 823                 perror("malloc");
 824                 return NULL;
 825         }
 826
 827         snprintf(name, namelen, "__pfx_%s", orig->name);
 828
 829         sym->name = name;
 830         sym->sec = orig->sec;
 831
 832         sym->sym.st_name = elf_add_string(elf, NULL, name);
 833         sym->sym.st_info = orig->sym.st_info;
 834         sym->sym.st_value = orig->sym.st_value - size;
 835         sym->sym.st_size = size;
 836
 837         sym = __elf_create_symbol(elf, sym);
 838         if (sym)
 839                 elf_add_symbol(elf, sym);
 840
 841         return sym;
 842 }
 843
 844 int elf_add_reloc_to_insn(struct elf *elf, struct section *sec,
 845                           unsigned long offset, unsigned int type,
 846                           struct section *insn_sec, unsigned long insn_off)
 847 {
 848         struct symbol *sym = insn_sec->sym;
 849         int addend = insn_off;
 850
 851         if (!sym) {
 852                 /*
 853                  * Due to how weak functions work, we must use section based
 854                  * relocations. Symbol based relocations would result in the
 855                  * weak and non-weak function annotations being overlaid on the
 856                  * non-weak function after linking.
 857                  */
 858                 sym = elf_create_section_symbol(elf, insn_sec);
 859                 if (!sym)
 860                         return -1;
 861
 862                 insn_sec->sym = sym;
 863         }
 864
 865         return elf_add_reloc(elf, sec, offset, type, sym, addend);
 866 }
 867
 868 static int read_rel_reloc(struct section *sec, int i, struct reloc *reloc, unsigned int *symndx)
 869 {
 870         if (!gelf_getrel(sec->data, i, &reloc->rel)) {
 871                 WARN_ELF("gelf_getrel");
 872                 return -1;
 873         }
 874         reloc->type = GELF_R_TYPE(reloc->rel.r_info);
 875         reloc->addend = 0;
 876         reloc->offset = reloc->rel.r_offset;
 877         *symndx = GELF_R_SYM(reloc->rel.r_info);
 878         return 0;
 879 }
 880
 881 static int read_rela_reloc(struct section *sec, int i, struct reloc *reloc, unsigned int *symndx)
 882 {
 883         if (!gelf_getrela(sec->data, i, &reloc->rela)) {
 884                 WARN_ELF("gelf_getrela");
 885                 return -1;
 886         }
 887         reloc->type = GELF_R_TYPE(reloc->rela.r_info);
 888         reloc->addend = reloc->rela.r_addend;
 889         reloc->offset = reloc->rela.r_offset;
 890         *symndx = GELF_R_SYM(reloc->rela.r_info);
 891         return 0;
 892 }
 893
 894 static int read_relocs(struct elf *elf)
 895 {
 896         unsigned long nr_reloc, max_reloc = 0, tot_reloc = 0;
 897         struct section *sec;
 898         struct reloc *reloc;
 899         unsigned int symndx;
 900         struct symbol *sym;
 901         int i;
 902
 903         if (!elf_alloc_hash(reloc, elf->text_size / 16))
 904                 return -1;
 905
 906         list_for_each_entry(sec, &elf->sections, list) {
 907                 if ((sec->sh.sh_type != SHT_RELA) &&
 908                     (sec->sh.sh_type != SHT_REL))
 909                         continue;
 910
 911                 sec->base = find_section_by_index(elf, sec->sh.sh_info);
 912                 if (!sec->base) {
 913                         WARN("can't find base section for reloc section %s",
 914                              sec->name);
 915                         return -1;
 916                 }
 917
 918                 sec->base->reloc = sec;
 919
 920                 nr_reloc = 0;
 921                 sec->reloc_data = calloc(sec->sh.sh_size / sec->sh.sh_entsize, sizeof(*reloc));
 922                 if (!sec->reloc_data) {
 923                         perror("calloc");
 924                         return -1;
 925                 }
 926                 for (i = 0; i < sec->sh.sh_size / sec->sh.sh_entsize; i++) {
 927                         reloc = &sec->reloc_data[i];
 928                         switch (sec->sh.sh_type) {
 929                         case SHT_REL:
 930                                 if (read_rel_reloc(sec, i, reloc, &symndx))
 931                                         return -1;
 932                                 break;
 933                         case SHT_RELA:
 934                                 if (read_rela_reloc(sec, i, reloc, &symndx))
 935                                         return -1;
 936                                 break;
 937                         default: return -1;
 938                         }
 939
 940                         reloc->sec = sec;
 941                         reloc->idx = i;
 942                         reloc->sym = sym = find_symbol_by_index(elf, symndx);
 943                         if (!reloc->sym) {
 944                                 WARN("can't find reloc entry symbol %d for %s",
 945                                      symndx, sec->name);
 946                                 return -1;
 947                         }
 948
 949                         list_add_tail(&reloc->sym_reloc_entry, &sym->reloc_list);
 950                         list_add_tail(&reloc->list, &sec->reloc_list);
 951                         elf_hash_add(reloc, &reloc->hash, reloc_hash(reloc));
 952
 953                         nr_reloc++;
 954                 }
 955                 max_reloc = max(max_reloc, nr_reloc);
 956                 tot_reloc += nr_reloc;
 957         }
 958
 959         if (opts.stats) {
 960                 printf("max_reloc: %lu\n", max_reloc);
 961                 printf("tot_reloc: %lu\n", tot_reloc);
 962                 printf("reloc_bits: %d\n", elf->reloc_bits);
 963         }
 964
 965         return 0;
 966 }
 967
 968 struct elf *elf_open_read(const char *name, int flags)
 969 {
 970         struct elf *elf;
 971         Elf_Cmd cmd;
 972
 973         elf_version(EV_CURRENT);
 974
 975         elf = malloc(sizeof(*elf));
 976         if (!elf) {
 977                 perror("malloc");
 978                 return NULL;
 979         }
 980         memset(elf, 0, offsetof(struct elf, sections));
 981
 982         INIT_LIST_HEAD(&elf->sections);
 983
 984         elf->fd = open(name, flags);
 985         if (elf->fd == -1) {
 986                 fprintf(stderr, "objtool: Can't open '%s': %s\n",
 987                         name, strerror(errno));
 988                 goto err;
 989         }
 990
 991         if ((flags & O_ACCMODE) == O_RDONLY)
 992                 cmd = ELF_C_READ_MMAP;
 993         else if ((flags & O_ACCMODE) == O_RDWR)
 994                 cmd = ELF_C_RDWR;
 995         else /* O_WRONLY */
 996                 cmd = ELF_C_WRITE;
 997
 998         elf->elf = elf_begin(elf->fd, cmd, NULL);
 999         if (!elf->elf) {
1000                 WARN_ELF("elf_begin");
1001                 goto err;
1002         }
1003
1004         if (!gelf_getehdr(elf->elf, &elf->ehdr)) {
1005                 WARN_ELF("gelf_getehdr");
1006                 goto err;
1007         }
1008
1009         if (read_sections(elf))
1010                 goto err;
1011
1012         if (read_symbols(elf))
1013                 goto err;
1014
1015         if (read_relocs(elf))
1016                 goto err;
1017
1018         return elf;
1019
1020 err:
1021         elf_close(elf);
1022         return NULL;
1023 }
1024
1025 static int elf_add_string(struct elf *elf, struct section *strtab, char *str)
1026 {
1027         Elf_Data *data;
1028         Elf_Scn *s;
1029         int len;
1030
1031         if (!strtab)
1032                 strtab = find_section_by_name(elf, ".strtab");
1033         if (!strtab) {
1034                 WARN("can't find .strtab section");
1035                 return -1;
1036         }
1037
1038         s = elf_getscn(elf->elf, strtab->idx);
1039         if (!s) {
1040                 WARN_ELF("elf_getscn");
1041                 return -1;
1042         }
1043
1044         data = elf_newdata(s);
1045         if (!data) {
1046                 WARN_ELF("elf_newdata");
1047                 return -1;
1048         }
1049
1050         data->d_buf = str;
1051         data->d_size = strlen(str) + 1;
1052         data->d_align = 1;
1053
1054         len = strtab->sh.sh_size;
1055         strtab->sh.sh_size += data->d_size;
1056         strtab->changed = true;
1057
1058         return len;
1059 }
1060
1061 struct section *elf_create_section(struct elf *elf, const char *name,
1062                                    unsigned int sh_flags, size_t entsize, int nr)
1063 {
1064         struct section *sec, *shstrtab;
1065         size_t size = entsize * nr;
1066         Elf_Scn *s;
1067
1068         sec = malloc(sizeof(*sec));
1069         if (!sec) {
1070                 perror("malloc");
1071                 return NULL;
1072         }
1073         memset(sec, 0, sizeof(*sec));
1074
1075         INIT_LIST_HEAD(&sec->symbol_list);
1076         INIT_LIST_HEAD(&sec->reloc_list);
1077
1078         s = elf_newscn(elf->elf);
1079         if (!s) {
1080                 WARN_ELF("elf_newscn");
1081                 return NULL;
1082         }
1083
1084         sec->name = strdup(name);
1085         if (!sec->name) {
1086                 perror("strdup");
1087                 return NULL;
1088         }
1089
1090         sec->idx = elf_ndxscn(s);
1091         sec->changed = true;
1092
1093         sec->data = elf_newdata(s);
1094         if (!sec->data) {
1095                 WARN_ELF("elf_newdata");
1096                 return NULL;
1097         }
1098
1099         sec->data->d_size = size;
1100         sec->data->d_align = 1;
1101
1102         if (size) {
1103                 sec->data->d_buf = malloc(size);
1104                 if (!sec->data->d_buf) {
1105                         perror("malloc");
1106                         return NULL;
1107                 }
1108                 memset(sec->data->d_buf, 0, size);
1109         }
1110
1111         if (!gelf_getshdr(s, &sec->sh)) {
1112                 WARN_ELF("gelf_getshdr");
1113                 return NULL;
1114         }
1115
1116         sec->sh.sh_size = size;
1117         sec->sh.sh_entsize = entsize;
1118         sec->sh.sh_type = SHT_PROGBITS;
1119         sec->sh.sh_addralign = 1;
1120         sec->sh.sh_flags = SHF_ALLOC | sh_flags;
1121
1122         /* Add section name to .shstrtab (or .strtab for Clang) */
1123         shstrtab = find_section_by_name(elf, ".shstrtab");
1124         if (!shstrtab)
1125                 shstrtab = find_section_by_name(elf, ".strtab");
1126         if (!shstrtab) {
1127                 WARN("can't find .shstrtab or .strtab section");
1128                 return NULL;
1129         }
1130         sec->sh.sh_name = elf_add_string(elf, shstrtab, sec->name);
1131         if (sec->sh.sh_name == -1)
1132                 return NULL;
1133
1134         list_add_tail(&sec->list, &elf->sections);
1135         elf_hash_add(section, &sec->hash, sec->idx);
1136         elf_hash_add(section_name, &sec->name_hash, str_hash(sec->name));
1137
1138         elf->changed = true;
1139
1140         return sec;
1141 }
1142
1143 static struct section *elf_create_rel_reloc_section(struct elf *elf, struct section *base)
1144 {
1145         char *relocname;
1146         struct section *sec;
1147
1148         relocname = malloc(strlen(base->name) + strlen(".rel") + 1);
1149         if (!relocname) {
1150                 perror("malloc");
1151                 return NULL;
1152         }
1153         strcpy(relocname, ".rel");
1154         strcat(relocname, base->name);
1155
1156         sec = elf_create_section(elf, relocname, 0, sizeof(GElf_Rel), 0);
1157         free(relocname);
1158         if (!sec)
1159                 return NULL;
1160
1161         base->reloc = sec;
1162         sec->base = base;
1163
1164         sec->sh.sh_type = SHT_REL;
1165         sec->sh.sh_addralign = 8;
1166         sec->sh.sh_link = find_section_by_name(elf, ".symtab")->idx;
1167         sec->sh.sh_info = base->idx;
1168         sec->sh.sh_flags = SHF_INFO_LINK;
1169
1170         return sec;
1171 }
1172
1173 static struct section *elf_create_rela_reloc_section(struct elf *elf, struct section *base)
1174 {
1175         char *relocname;
1176         struct section *sec;
1177         int addrsize = elf_class_addrsize(elf);
1178
1179         relocname = malloc(strlen(base->name) + strlen(".rela") + 1);
1180         if (!relocname) {
1181                 perror("malloc");
1182                 return NULL;
1183         }
1184         strcpy(relocname, ".rela");
1185         strcat(relocname, base->name);
1186
1187         if (addrsize == sizeof(u32))
1188                 sec = elf_create_section(elf, relocname, 0, sizeof(Elf32_Rela), 0);
1189         else
1190                 sec = elf_create_section(elf, relocname, 0, sizeof(GElf_Rela), 0);
1191         free(relocname);
1192         if (!sec)
1193                 return NULL;
1194
1195         base->reloc = sec;
1196         sec->base = base;
1197
1198         sec->sh.sh_type = SHT_RELA;
1199         sec->sh.sh_addralign = addrsize;
1200         sec->sh.sh_link = find_section_by_name(elf, ".symtab")->idx;
1201         sec->sh.sh_info = base->idx;
1202         sec->sh.sh_flags = SHF_INFO_LINK;
1203
1204         return sec;
1205 }
1206
1207 static struct section *elf_create_reloc_section(struct elf *elf,
1208                                          struct section *base,
1209                                          int reltype)
1210 {
1211         switch (reltype) {
1212         case SHT_REL:  return elf_create_rel_reloc_section(elf, base);
1213         case SHT_RELA: return elf_create_rela_reloc_section(elf, base);
1214         default:       return NULL;
1215         }
1216 }
1217
1218 static int elf_rebuild_rel_reloc_section(struct section *sec)
1219 {
1220         struct reloc *reloc;
1221         int idx = 0;
1222         void *buf;
1223
1224         /* Allocate a buffer for relocations */
1225         buf = malloc(sec->sh.sh_size);
1226         if (!buf) {
1227                 perror("malloc");
1228                 return -1;
1229         }
1230
1231         sec->data->d_buf = buf;
1232         sec->data->d_size = sec->sh.sh_size;
1233         sec->data->d_type = ELF_T_REL;
1234
1235         idx = 0;
1236         list_for_each_entry(reloc, &sec->reloc_list, list) {
1237                 reloc->rel.r_offset = reloc->offset;
1238                 reloc->rel.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);
1239                 if (!gelf_update_rel(sec->data, idx, &reloc->rel)) {
1240                         WARN_ELF("gelf_update_rel");
1241                         return -1;
1242                 }
1243                 idx++;
1244         }
1245
1246         return 0;
1247 }
1248
1249 static int elf_rebuild_rela_reloc_section(struct section *sec)
1250 {
1251         struct reloc *reloc;
1252         int idx = 0;
1253         void *buf;
1254
1255         /* Allocate a buffer for relocations with addends */
1256         buf = malloc(sec->sh.sh_size);
1257         if (!buf) {
1258                 perror("malloc");
1259                 return -1;
1260         }
1261
1262         sec->data->d_buf = buf;
1263         sec->data->d_size = sec->sh.sh_size;
1264         sec->data->d_type = ELF_T_RELA;
1265
1266         idx = 0;
1267         list_for_each_entry(reloc, &sec->reloc_list, list) {
1268                 reloc->rela.r_offset = reloc->offset;
1269                 reloc->rela.r_addend = reloc->addend;
1270                 reloc->rela.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);
1271                 if (!gelf_update_rela(sec->data, idx, &reloc->rela)) {
1272                         WARN_ELF("gelf_update_rela");
1273                         return -1;
1274                 }
1275                 idx++;
1276         }
1277
1278         return 0;
1279 }
1280
1281 static int elf_rebuild_reloc_section(struct elf *elf, struct section *sec)
1282 {
1283         switch (sec->sh.sh_type) {
1284         case SHT_REL:  return elf_rebuild_rel_reloc_section(sec);
1285         case SHT_RELA: return elf_rebuild_rela_reloc_section(sec);
1286         default:       return -1;
1287         }
1288 }
1289
1290 int elf_write_insn(struct elf *elf, struct section *sec,
1291                    unsigned long offset, unsigned int len,
1292                    const char *insn)
1293 {
1294         Elf_Data *data = sec->data;
1295
1296         if (data->d_type != ELF_T_BYTE || data->d_off) {
1297                 WARN("write to unexpected data for section: %s", sec->name);
1298                 return -1;
1299         }
1300
1301         memcpy(data->d_buf + offset, insn, len);
1302         elf_flagdata(data, ELF_C_SET, ELF_F_DIRTY);
1303
1304         elf->changed = true;
1305
1306         return 0;
1307 }
1308
1309 int elf_write_reloc(struct elf *elf, struct reloc *reloc)
1310 {
1311         struct section *sec = reloc->sec;
1312
1313         if (sec->sh.sh_type == SHT_REL) {
1314                 reloc->rel.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);
1315                 reloc->rel.r_offset = reloc->offset;
1316
1317                 if (!gelf_update_rel(sec->data, reloc->idx, &reloc->rel)) {
1318                         WARN_ELF("gelf_update_rel");
1319                         return -1;
1320                 }
1321         } else {
1322                 reloc->rela.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);
1323                 reloc->rela.r_addend = reloc->addend;
1324                 reloc->rela.r_offset = reloc->offset;
1325
1326                 if (!gelf_update_rela(sec->data, reloc->idx, &reloc->rela)) {
1327                         WARN_ELF("gelf_update_rela");
1328                         return -1;
1329                 }
1330         }
1331
1332         elf->changed = true;
1333
1334         return 0;
1335 }
1336
1337 /*
1338  * When Elf_Scn::sh_size is smaller than the combined Elf_Data::d_size
1339  * do you:
1340  *
1341  *   A) adhere to the section header and truncate the data, or
1342  *   B) ignore the section header and write out all the data you've got?
1343  *
1344  * Yes, libelf sucks and we need to manually truncate if we over-allocate data.
1345  */
1346 static int elf_truncate_section(struct elf *elf, struct section *sec)
1347 {
1348         u64 size = sec->sh.sh_size;
1349         bool truncated = false;
1350         Elf_Data *data = NULL;
1351         Elf_Scn *s;
1352
1353         s = elf_getscn(elf->elf, sec->idx);
1354         if (!s) {
1355                 WARN_ELF("elf_getscn");
1356                 return -1;
1357         }
1358
1359         for (;;) {
1360                 /* get next data descriptor for the relevant section */
1361                 data = elf_getdata(s, data);
1362
1363                 if (!data) {
1364                         if (size) {
1365                                 WARN("end of section data but non-zero size left\n");
1366                                 return -1;
1367                         }
1368                         return 0;
1369                 }
1370
1371                 if (truncated) {
1372                         /* when we remove symbols */
1373                         WARN("truncated; but more data\n");
1374                         return -1;
1375                 }
1376
1377                 if (!data->d_size) {
1378                         WARN("zero size data");
1379                         return -1;
1380                 }
1381
1382                 if (data->d_size > size) {
1383                         truncated = true;
1384                         data->d_size = size;
1385                 }
1386
1387                 size -= data->d_size;
1388         }
1389 }
1390
1391 int elf_write(struct elf *elf)
1392 {
1393         struct section *sec;
1394         Elf_Scn *s;
1395
1396         if (opts.dryrun)
1397                 return 0;
1398
1399         /* Update changed relocation sections and section headers: */
1400         list_for_each_entry(sec, &elf->sections, list) {
1401                 if (sec->truncate)
1402                         elf_truncate_section(elf, sec);
1403
1404                 if (sec->changed) {
1405                         s = elf_getscn(elf->elf, sec->idx);
1406                         if (!s) {
1407                                 WARN_ELF("elf_getscn");
1408                                 return -1;
1409                         }
1410                         if (!gelf_update_shdr(s, &sec->sh)) {
1411                                 WARN_ELF("gelf_update_shdr");
1412                                 return -1;
1413                         }
1414
1415                         if (sec->base &&
1416                             elf_rebuild_reloc_section(elf, sec)) {
1417                                 WARN("elf_rebuild_reloc_section");
1418                                 return -1;
1419                         }
1420
1421                         sec->changed = false;
1422                         elf->changed = true;
1423                 }
1424         }
1425
1426         /* Make sure the new section header entries get updated properly. */
1427         elf_flagelf(elf->elf, ELF_C_SET, ELF_F_DIRTY);
1428
1429         /* Write all changes to the file. */
1430         if (elf_update(elf->elf, ELF_C_WRITE) < 0) {
1431                 WARN_ELF("elf_update");
1432                 return -1;
1433         }
1434
1435         elf->changed = false;
1436
1437         return 0;
1438 }
1439
1440 void elf_close(struct elf *elf)
1441 {
1442         struct section *sec, *tmpsec;
1443         struct symbol *sym, *tmpsym;
1444         struct reloc *reloc, *tmpreloc;
1445
1446         if (elf->elf)
1447                 elf_end(elf->elf);
1448
1449         if (elf->fd > 0)
1450                 close(elf->fd);
1451
1452         list_for_each_entry_safe(sec, tmpsec, &elf->sections, list) {
1453                 list_for_each_entry_safe(sym, tmpsym, &sec->symbol_list, list) {
1454                         list_del(&sym->list);
1455                         hash_del(&sym->hash);
1456                 }
1457                 list_for_each_entry_safe(reloc, tmpreloc, &sec->reloc_list, list) {
1458                         list_del(&reloc->list);
1459                         hash_del(&reloc->hash);
1460                 }
1461                 list_del(&sec->list);
1462                 free(sec->reloc_data);
1463         }
1464
1465         free(elf->symbol_data);
1466         free(elf->section_data);
1467         free(elf);
1468 }