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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 <fcntl.h>
13#include <stdio.h>
14#include <stdlib.h>
15#include <string.h>
16#include <unistd.h>
17#include <errno.h>
18#include "builtin.h"
19
20#include "elf.h"
21#include "warn.h"
22
23#define MAX_NAME_LEN 128
24
25static inline u32 str_hash(const char *str)
26{
27 return jhash(str, strlen(str), 0);
28}
29
30static inline int elf_hash_bits(void)
31{
32 return vmlinux ? ELF_HASH_BITS : 16;
33}
34
35#define elf_hash_add(hashtable, node, key) \
36 hlist_add_head(node, &hashtable[hash_min(key, elf_hash_bits())])
37
38static void elf_hash_init(struct hlist_head *table)
39{
40 __hash_init(table, 1U << elf_hash_bits());
41}
42
43#define elf_hash_for_each_possible(name, obj, member, key) \
44 hlist_for_each_entry(obj, &name[hash_min(key, elf_hash_bits())], member)
45
46static void rb_add(struct rb_root *tree, struct rb_node *node,
47 int (*cmp)(struct rb_node *, const struct rb_node *))
48{
49 struct rb_node **link = &tree->rb_node;
50 struct rb_node *parent = NULL;
51
52 while (*link) {
53 parent = *link;
54 if (cmp(node, parent) < 0)
55 link = &parent->rb_left;
56 else
57 link = &parent->rb_right;
58 }
59
60 rb_link_node(node, parent, link);
61 rb_insert_color(node, tree);
62}
63
64static struct rb_node *rb_find_first(const struct rb_root *tree, const void *key,
65 int (*cmp)(const void *key, const struct rb_node *))
66{
67 struct rb_node *node = tree->rb_node;
68 struct rb_node *match = NULL;
69
70 while (node) {
71 int c = cmp(key, node);
72 if (c <= 0) {
73 if (!c)
74 match = node;
75 node = node->rb_left;
76 } else if (c > 0) {
77 node = node->rb_right;
78 }
79 }
80
81 return match;
82}
83
84static struct rb_node *rb_next_match(struct rb_node *node, const void *key,
85 int (*cmp)(const void *key, const struct rb_node *))
86{
87 node = rb_next(node);
88 if (node && cmp(key, node))
89 node = NULL;
90 return node;
91}
92
93#define rb_for_each(tree, node, key, cmp) \
94 for ((node) = rb_find_first((tree), (key), (cmp)); \
95 (node); (node) = rb_next_match((node), (key), (cmp)))
96
97static int symbol_to_offset(struct rb_node *a, const struct rb_node *b)
98{
99 struct symbol *sa = rb_entry(a, struct symbol, node);
100 struct symbol *sb = rb_entry(b, struct symbol, node);
101
102 if (sa->offset < sb->offset)
103 return -1;
104 if (sa->offset > sb->offset)
105 return 1;
106
107 if (sa->len < sb->len)
108 return -1;
109 if (sa->len > sb->len)
110 return 1;
111
112 sa->alias = sb;
113
114 return 0;
115}
116
117static int symbol_by_offset(const void *key, const struct rb_node *node)
118{
119 const struct symbol *s = rb_entry(node, struct symbol, node);
120 const unsigned long *o = key;
121
122 if (*o < s->offset)
123 return -1;
124 if (*o >= s->offset + s->len)
125 return 1;
126
127 return 0;
128}
129
130struct section *find_section_by_name(const struct elf *elf, const char *name)
131{
132 struct section *sec;
133
134 elf_hash_for_each_possible(elf->section_name_hash, sec, name_hash, str_hash(name))
135 if (!strcmp(sec->name, name))
136 return sec;
137
138 return NULL;
139}
140
141static struct section *find_section_by_index(struct elf *elf,
142 unsigned int idx)
143{
144 struct section *sec;
145
146 elf_hash_for_each_possible(elf->section_hash, sec, hash, idx)
147 if (sec->idx == idx)
148 return sec;
149
150 return NULL;
151}
152
153static struct symbol *find_symbol_by_index(struct elf *elf, unsigned int idx)
154{
155 struct symbol *sym;
156
157 elf_hash_for_each_possible(elf->symbol_hash, sym, hash, idx)
158 if (sym->idx == idx)
159 return sym;
160
161 return NULL;
162}
163
164struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset)
165{
166 struct rb_node *node;
167
168 rb_for_each(&sec->symbol_tree, node, &offset, symbol_by_offset) {
169 struct symbol *s = rb_entry(node, struct symbol, node);
170
171 if (s->offset == offset && s->type != STT_SECTION)
172 return s;
173 }
174
175 return NULL;
176}
177
178struct symbol *find_func_by_offset(struct section *sec, unsigned long offset)
179{
180 struct rb_node *node;
181
182 rb_for_each(&sec->symbol_tree, node, &offset, symbol_by_offset) {
183 struct symbol *s = rb_entry(node, struct symbol, node);
184
185 if (s->offset == offset && s->type == STT_FUNC)
186 return s;
187 }
188
189 return NULL;
190}
191
192struct symbol *find_symbol_containing(const struct section *sec, unsigned long offset)
193{
194 struct rb_node *node;
195
196 rb_for_each(&sec->symbol_tree, node, &offset, symbol_by_offset) {
197 struct symbol *s = rb_entry(node, struct symbol, node);
198
199 if (s->type != STT_SECTION)
200 return s;
201 }
202
203 return NULL;
204}
205
206struct symbol *find_func_containing(struct section *sec, unsigned long offset)
207{
208 struct rb_node *node;
209
210 rb_for_each(&sec->symbol_tree, node, &offset, symbol_by_offset) {
211 struct symbol *s = rb_entry(node, struct symbol, node);
212
213 if (s->type == STT_FUNC)
214 return s;
215 }
216
217 return NULL;
218}
219
220struct symbol *find_symbol_by_name(const struct elf *elf, const char *name)
221{
222 struct symbol *sym;
223
224 elf_hash_for_each_possible(elf->symbol_name_hash, sym, name_hash, str_hash(name))
225 if (!strcmp(sym->name, name))
226 return sym;
227
228 return NULL;
229}
230
231struct reloc *find_reloc_by_dest_range(const struct elf *elf, struct section *sec,
232 unsigned long offset, unsigned int len)
233{
234 struct reloc *reloc, *r = NULL;
235 unsigned long o;
236
237 if (!sec->reloc)
238 return NULL;
239
240 sec = sec->reloc;
241
242 for_offset_range(o, offset, offset + len) {
243 elf_hash_for_each_possible(elf->reloc_hash, reloc, hash,
244 sec_offset_hash(sec, o)) {
245 if (reloc->sec != sec)
246 continue;
247
248 if (reloc->offset >= offset && reloc->offset < offset + len) {
249 if (!r || reloc->offset < r->offset)
250 r = reloc;
251 }
252 }
253 if (r)
254 return r;
255 }
256
257 return NULL;
258}
259
260struct reloc *find_reloc_by_dest(const struct elf *elf, struct section *sec, unsigned long offset)
261{
262 return find_reloc_by_dest_range(elf, sec, offset, 1);
263}
264
265static int read_sections(struct elf *elf)
266{
267 Elf_Scn *s = NULL;
268 struct section *sec;
269 size_t shstrndx, sections_nr;
270 int i;
271
272 if (elf_getshdrnum(elf->elf, §ions_nr)) {
273 WARN_ELF("elf_getshdrnum");
274 return -1;
275 }
276
277 if (elf_getshdrstrndx(elf->elf, &shstrndx)) {
278 WARN_ELF("elf_getshdrstrndx");
279 return -1;
280 }
281
282 for (i = 0; i < sections_nr; i++) {
283 sec = malloc(sizeof(*sec));
284 if (!sec) {
285 perror("malloc");
286 return -1;
287 }
288 memset(sec, 0, sizeof(*sec));
289
290 INIT_LIST_HEAD(&sec->symbol_list);
291 INIT_LIST_HEAD(&sec->reloc_list);
292
293 s = elf_getscn(elf->elf, i);
294 if (!s) {
295 WARN_ELF("elf_getscn");
296 return -1;
297 }
298
299 sec->idx = elf_ndxscn(s);
300
301 if (!gelf_getshdr(s, &sec->sh)) {
302 WARN_ELF("gelf_getshdr");
303 return -1;
304 }
305
306 sec->name = elf_strptr(elf->elf, shstrndx, sec->sh.sh_name);
307 if (!sec->name) {
308 WARN_ELF("elf_strptr");
309 return -1;
310 }
311
312 if (sec->sh.sh_size != 0) {
313 sec->data = elf_getdata(s, NULL);
314 if (!sec->data) {
315 WARN_ELF("elf_getdata");
316 return -1;
317 }
318 if (sec->data->d_off != 0 ||
319 sec->data->d_size != sec->sh.sh_size) {
320 WARN("unexpected data attributes for %s",
321 sec->name);
322 return -1;
323 }
324 }
325 sec->len = sec->sh.sh_size;
326
327 list_add_tail(&sec->list, &elf->sections);
328 elf_hash_add(elf->section_hash, &sec->hash, sec->idx);
329 elf_hash_add(elf->section_name_hash, &sec->name_hash, str_hash(sec->name));
330 }
331
332 if (stats)
333 printf("nr_sections: %lu\n", (unsigned long)sections_nr);
334
335 /* sanity check, one more call to elf_nextscn() should return NULL */
336 if (elf_nextscn(elf->elf, s)) {
337 WARN("section entry mismatch");
338 return -1;
339 }
340
341 return 0;
342}
343
344static int read_symbols(struct elf *elf)
345{
346 struct section *symtab, *symtab_shndx, *sec;
347 struct symbol *sym, *pfunc;
348 struct list_head *entry;
349 struct rb_node *pnode;
350 int symbols_nr, i;
351 char *coldstr;
352 Elf_Data *shndx_data = NULL;
353 Elf32_Word shndx;
354
355 symtab = find_section_by_name(elf, ".symtab");
356 if (!symtab) {
357 WARN("missing symbol table");
358 return -1;
359 }
360
361 symtab_shndx = find_section_by_name(elf, ".symtab_shndx");
362 if (symtab_shndx)
363 shndx_data = symtab_shndx->data;
364
365 symbols_nr = symtab->sh.sh_size / symtab->sh.sh_entsize;
366
367 for (i = 0; i < symbols_nr; i++) {
368 sym = malloc(sizeof(*sym));
369 if (!sym) {
370 perror("malloc");
371 return -1;
372 }
373 memset(sym, 0, sizeof(*sym));
374 sym->alias = sym;
375
376 sym->idx = i;
377
378 if (!gelf_getsymshndx(symtab->data, shndx_data, i, &sym->sym,
379 &shndx)) {
380 WARN_ELF("gelf_getsymshndx");
381 goto err;
382 }
383
384 sym->name = elf_strptr(elf->elf, symtab->sh.sh_link,
385 sym->sym.st_name);
386 if (!sym->name) {
387 WARN_ELF("elf_strptr");
388 goto err;
389 }
390
391 sym->type = GELF_ST_TYPE(sym->sym.st_info);
392 sym->bind = GELF_ST_BIND(sym->sym.st_info);
393
394 if ((sym->sym.st_shndx > SHN_UNDEF &&
395 sym->sym.st_shndx < SHN_LORESERVE) ||
396 (shndx_data && sym->sym.st_shndx == SHN_XINDEX)) {
397 if (sym->sym.st_shndx != SHN_XINDEX)
398 shndx = sym->sym.st_shndx;
399
400 sym->sec = find_section_by_index(elf, shndx);
401 if (!sym->sec) {
402 WARN("couldn't find section for symbol %s",
403 sym->name);
404 goto err;
405 }
406 if (sym->type == STT_SECTION) {
407 sym->name = sym->sec->name;
408 sym->sec->sym = sym;
409 }
410 } else
411 sym->sec = find_section_by_index(elf, 0);
412
413 sym->offset = sym->sym.st_value;
414 sym->len = sym->sym.st_size;
415
416 rb_add(&sym->sec->symbol_tree, &sym->node, symbol_to_offset);
417 pnode = rb_prev(&sym->node);
418 if (pnode)
419 entry = &rb_entry(pnode, struct symbol, node)->list;
420 else
421 entry = &sym->sec->symbol_list;
422 list_add(&sym->list, entry);
423 elf_hash_add(elf->symbol_hash, &sym->hash, sym->idx);
424 elf_hash_add(elf->symbol_name_hash, &sym->name_hash, str_hash(sym->name));
425 }
426
427 if (stats)
428 printf("nr_symbols: %lu\n", (unsigned long)symbols_nr);
429
430 /* Create parent/child links for any cold subfunctions */
431 list_for_each_entry(sec, &elf->sections, list) {
432 list_for_each_entry(sym, &sec->symbol_list, list) {
433 char pname[MAX_NAME_LEN + 1];
434 size_t pnamelen;
435 if (sym->type != STT_FUNC)
436 continue;
437
438 if (sym->pfunc == NULL)
439 sym->pfunc = sym;
440
441 if (sym->cfunc == NULL)
442 sym->cfunc = sym;
443
444 coldstr = strstr(sym->name, ".cold");
445 if (!coldstr)
446 continue;
447
448 pnamelen = coldstr - sym->name;
449 if (pnamelen > MAX_NAME_LEN) {
450 WARN("%s(): parent function name exceeds maximum length of %d characters",
451 sym->name, MAX_NAME_LEN);
452 return -1;
453 }
454
455 strncpy(pname, sym->name, pnamelen);
456 pname[pnamelen] = '\0';
457 pfunc = find_symbol_by_name(elf, pname);
458
459 if (!pfunc) {
460 WARN("%s(): can't find parent function",
461 sym->name);
462 return -1;
463 }
464
465 sym->pfunc = pfunc;
466 pfunc->cfunc = sym;
467
468 /*
469 * Unfortunately, -fnoreorder-functions puts the child
470 * inside the parent. Remove the overlap so we can
471 * have sane assumptions.
472 *
473 * Note that pfunc->len now no longer matches
474 * pfunc->sym.st_size.
475 */
476 if (sym->sec == pfunc->sec &&
477 sym->offset >= pfunc->offset &&
478 sym->offset + sym->len == pfunc->offset + pfunc->len) {
479 pfunc->len -= sym->len;
480 }
481 }
482 }
483
484 return 0;
485
486err:
487 free(sym);
488 return -1;
489}
490
491void elf_add_reloc(struct elf *elf, struct reloc *reloc)
492{
493 struct section *sec = reloc->sec;
494
495 list_add_tail(&reloc->list, &sec->reloc_list);
496 elf_hash_add(elf->reloc_hash, &reloc->hash, reloc_hash(reloc));
497}
498
499static int read_rel_reloc(struct section *sec, int i, struct reloc *reloc, unsigned int *symndx)
500{
501 if (!gelf_getrel(sec->data, i, &reloc->rel)) {
502 WARN_ELF("gelf_getrel");
503 return -1;
504 }
505 reloc->type = GELF_R_TYPE(reloc->rel.r_info);
506 reloc->addend = 0;
507 reloc->offset = reloc->rel.r_offset;
508 *symndx = GELF_R_SYM(reloc->rel.r_info);
509 return 0;
510}
511
512static int read_rela_reloc(struct section *sec, int i, struct reloc *reloc, unsigned int *symndx)
513{
514 if (!gelf_getrela(sec->data, i, &reloc->rela)) {
515 WARN_ELF("gelf_getrela");
516 return -1;
517 }
518 reloc->type = GELF_R_TYPE(reloc->rela.r_info);
519 reloc->addend = reloc->rela.r_addend;
520 reloc->offset = reloc->rela.r_offset;
521 *symndx = GELF_R_SYM(reloc->rela.r_info);
522 return 0;
523}
524
525static int read_relocs(struct elf *elf)
526{
527 struct section *sec;
528 struct reloc *reloc;
529 int i;
530 unsigned int symndx;
531 unsigned long nr_reloc, max_reloc = 0, tot_reloc = 0;
532
533 list_for_each_entry(sec, &elf->sections, list) {
534 if ((sec->sh.sh_type != SHT_RELA) &&
535 (sec->sh.sh_type != SHT_REL))
536 continue;
537
538 sec->base = find_section_by_index(elf, sec->sh.sh_info);
539 if (!sec->base) {
540 WARN("can't find base section for reloc section %s",
541 sec->name);
542 return -1;
543 }
544
545 sec->base->reloc = sec;
546
547 nr_reloc = 0;
548 for (i = 0; i < sec->sh.sh_size / sec->sh.sh_entsize; i++) {
549 reloc = malloc(sizeof(*reloc));
550 if (!reloc) {
551 perror("malloc");
552 return -1;
553 }
554 memset(reloc, 0, sizeof(*reloc));
555 switch (sec->sh.sh_type) {
556 case SHT_REL:
557 if (read_rel_reloc(sec, i, reloc, &symndx))
558 return -1;
559 break;
560 case SHT_RELA:
561 if (read_rela_reloc(sec, i, reloc, &symndx))
562 return -1;
563 break;
564 default: return -1;
565 }
566
567 reloc->sec = sec;
568 reloc->idx = i;
569 reloc->sym = find_symbol_by_index(elf, symndx);
570 if (!reloc->sym) {
571 WARN("can't find reloc entry symbol %d for %s",
572 symndx, sec->name);
573 return -1;
574 }
575
576 elf_add_reloc(elf, reloc);
577 nr_reloc++;
578 }
579 max_reloc = max(max_reloc, nr_reloc);
580 tot_reloc += nr_reloc;
581 }
582
583 if (stats) {
584 printf("max_reloc: %lu\n", max_reloc);
585 printf("tot_reloc: %lu\n", tot_reloc);
586 }
587
588 return 0;
589}
590
591struct elf *elf_open_read(const char *name, int flags)
592{
593 struct elf *elf;
594 Elf_Cmd cmd;
595
596 elf_version(EV_CURRENT);
597
598 elf = malloc(sizeof(*elf));
599 if (!elf) {
600 perror("malloc");
601 return NULL;
602 }
603 memset(elf, 0, offsetof(struct elf, sections));
604
605 INIT_LIST_HEAD(&elf->sections);
606
607 elf_hash_init(elf->symbol_hash);
608 elf_hash_init(elf->symbol_name_hash);
609 elf_hash_init(elf->section_hash);
610 elf_hash_init(elf->section_name_hash);
611 elf_hash_init(elf->reloc_hash);
612
613 elf->fd = open(name, flags);
614 if (elf->fd == -1) {
615 fprintf(stderr, "objtool: Can't open '%s': %s\n",
616 name, strerror(errno));
617 goto err;
618 }
619
620 if ((flags & O_ACCMODE) == O_RDONLY)
621 cmd = ELF_C_READ_MMAP;
622 else if ((flags & O_ACCMODE) == O_RDWR)
623 cmd = ELF_C_RDWR;
624 else /* O_WRONLY */
625 cmd = ELF_C_WRITE;
626
627 elf->elf = elf_begin(elf->fd, cmd, NULL);
628 if (!elf->elf) {
629 WARN_ELF("elf_begin");
630 goto err;
631 }
632
633 if (!gelf_getehdr(elf->elf, &elf->ehdr)) {
634 WARN_ELF("gelf_getehdr");
635 goto err;
636 }
637
638 if (read_sections(elf))
639 goto err;
640
641 if (read_symbols(elf))
642 goto err;
643
644 if (read_relocs(elf))
645 goto err;
646
647 return elf;
648
649err:
650 elf_close(elf);
651 return NULL;
652}
653
654struct section *elf_create_section(struct elf *elf, const char *name,
655 size_t entsize, int nr)
656{
657 struct section *sec, *shstrtab;
658 size_t size = entsize * nr;
659 Elf_Scn *s;
660 Elf_Data *data;
661
662 sec = malloc(sizeof(*sec));
663 if (!sec) {
664 perror("malloc");
665 return NULL;
666 }
667 memset(sec, 0, sizeof(*sec));
668
669 INIT_LIST_HEAD(&sec->symbol_list);
670 INIT_LIST_HEAD(&sec->reloc_list);
671
672 s = elf_newscn(elf->elf);
673 if (!s) {
674 WARN_ELF("elf_newscn");
675 return NULL;
676 }
677
678 sec->name = strdup(name);
679 if (!sec->name) {
680 perror("strdup");
681 return NULL;
682 }
683
684 sec->idx = elf_ndxscn(s);
685 sec->len = size;
686 sec->changed = true;
687
688 sec->data = elf_newdata(s);
689 if (!sec->data) {
690 WARN_ELF("elf_newdata");
691 return NULL;
692 }
693
694 sec->data->d_size = size;
695 sec->data->d_align = 1;
696
697 if (size) {
698 sec->data->d_buf = malloc(size);
699 if (!sec->data->d_buf) {
700 perror("malloc");
701 return NULL;
702 }
703 memset(sec->data->d_buf, 0, size);
704 }
705
706 if (!gelf_getshdr(s, &sec->sh)) {
707 WARN_ELF("gelf_getshdr");
708 return NULL;
709 }
710
711 sec->sh.sh_size = size;
712 sec->sh.sh_entsize = entsize;
713 sec->sh.sh_type = SHT_PROGBITS;
714 sec->sh.sh_addralign = 1;
715 sec->sh.sh_flags = SHF_ALLOC;
716
717
718 /* Add section name to .shstrtab (or .strtab for Clang) */
719 shstrtab = find_section_by_name(elf, ".shstrtab");
720 if (!shstrtab)
721 shstrtab = find_section_by_name(elf, ".strtab");
722 if (!shstrtab) {
723 WARN("can't find .shstrtab or .strtab section");
724 return NULL;
725 }
726
727 s = elf_getscn(elf->elf, shstrtab->idx);
728 if (!s) {
729 WARN_ELF("elf_getscn");
730 return NULL;
731 }
732
733 data = elf_newdata(s);
734 if (!data) {
735 WARN_ELF("elf_newdata");
736 return NULL;
737 }
738
739 data->d_buf = sec->name;
740 data->d_size = strlen(name) + 1;
741 data->d_align = 1;
742
743 sec->sh.sh_name = shstrtab->len;
744
745 shstrtab->len += strlen(name) + 1;
746 shstrtab->changed = true;
747
748 list_add_tail(&sec->list, &elf->sections);
749 elf_hash_add(elf->section_hash, &sec->hash, sec->idx);
750 elf_hash_add(elf->section_name_hash, &sec->name_hash, str_hash(sec->name));
751
752 elf->changed = true;
753
754 return sec;
755}
756
757static struct section *elf_create_rel_reloc_section(struct elf *elf, struct section *base)
758{
759 char *relocname;
760 struct section *sec;
761
762 relocname = malloc(strlen(base->name) + strlen(".rel") + 1);
763 if (!relocname) {
764 perror("malloc");
765 return NULL;
766 }
767 strcpy(relocname, ".rel");
768 strcat(relocname, base->name);
769
770 sec = elf_create_section(elf, relocname, sizeof(GElf_Rel), 0);
771 free(relocname);
772 if (!sec)
773 return NULL;
774
775 base->reloc = sec;
776 sec->base = base;
777
778 sec->sh.sh_type = SHT_REL;
779 sec->sh.sh_addralign = 8;
780 sec->sh.sh_link = find_section_by_name(elf, ".symtab")->idx;
781 sec->sh.sh_info = base->idx;
782 sec->sh.sh_flags = SHF_INFO_LINK;
783
784 return sec;
785}
786
787static struct section *elf_create_rela_reloc_section(struct elf *elf, struct section *base)
788{
789 char *relocname;
790 struct section *sec;
791
792 relocname = malloc(strlen(base->name) + strlen(".rela") + 1);
793 if (!relocname) {
794 perror("malloc");
795 return NULL;
796 }
797 strcpy(relocname, ".rela");
798 strcat(relocname, base->name);
799
800 sec = elf_create_section(elf, relocname, sizeof(GElf_Rela), 0);
801 free(relocname);
802 if (!sec)
803 return NULL;
804
805 base->reloc = sec;
806 sec->base = base;
807
808 sec->sh.sh_type = SHT_RELA;
809 sec->sh.sh_addralign = 8;
810 sec->sh.sh_link = find_section_by_name(elf, ".symtab")->idx;
811 sec->sh.sh_info = base->idx;
812 sec->sh.sh_flags = SHF_INFO_LINK;
813
814 return sec;
815}
816
817struct section *elf_create_reloc_section(struct elf *elf,
818 struct section *base,
819 int reltype)
820{
821 switch (reltype) {
822 case SHT_REL: return elf_create_rel_reloc_section(elf, base);
823 case SHT_RELA: return elf_create_rela_reloc_section(elf, base);
824 default: return NULL;
825 }
826}
827
828static int elf_rebuild_rel_reloc_section(struct section *sec, int nr)
829{
830 struct reloc *reloc;
831 int idx = 0, size;
832 GElf_Rel *relocs;
833
834 /* Allocate a buffer for relocations */
835 size = nr * sizeof(*relocs);
836 relocs = malloc(size);
837 if (!relocs) {
838 perror("malloc");
839 return -1;
840 }
841
842 sec->data->d_buf = relocs;
843 sec->data->d_size = size;
844
845 sec->sh.sh_size = size;
846
847 idx = 0;
848 list_for_each_entry(reloc, &sec->reloc_list, list) {
849 relocs[idx].r_offset = reloc->offset;
850 relocs[idx].r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);
851 idx++;
852 }
853
854 return 0;
855}
856
857static int elf_rebuild_rela_reloc_section(struct section *sec, int nr)
858{
859 struct reloc *reloc;
860 int idx = 0, size;
861 GElf_Rela *relocs;
862
863 /* Allocate a buffer for relocations with addends */
864 size = nr * sizeof(*relocs);
865 relocs = malloc(size);
866 if (!relocs) {
867 perror("malloc");
868 return -1;
869 }
870
871 sec->data->d_buf = relocs;
872 sec->data->d_size = size;
873
874 sec->sh.sh_size = size;
875
876 idx = 0;
877 list_for_each_entry(reloc, &sec->reloc_list, list) {
878 relocs[idx].r_offset = reloc->offset;
879 relocs[idx].r_addend = reloc->addend;
880 relocs[idx].r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);
881 idx++;
882 }
883
884 return 0;
885}
886
887int elf_rebuild_reloc_section(struct elf *elf, struct section *sec)
888{
889 struct reloc *reloc;
890 int nr;
891
892 sec->changed = true;
893 elf->changed = true;
894
895 nr = 0;
896 list_for_each_entry(reloc, &sec->reloc_list, list)
897 nr++;
898
899 switch (sec->sh.sh_type) {
900 case SHT_REL: return elf_rebuild_rel_reloc_section(sec, nr);
901 case SHT_RELA: return elf_rebuild_rela_reloc_section(sec, nr);
902 default: return -1;
903 }
904}
905
906int elf_write_insn(struct elf *elf, struct section *sec,
907 unsigned long offset, unsigned int len,
908 const char *insn)
909{
910 Elf_Data *data = sec->data;
911
912 if (data->d_type != ELF_T_BYTE || data->d_off) {
913 WARN("write to unexpected data for section: %s", sec->name);
914 return -1;
915 }
916
917 memcpy(data->d_buf + offset, insn, len);
918 elf_flagdata(data, ELF_C_SET, ELF_F_DIRTY);
919
920 elf->changed = true;
921
922 return 0;
923}
924
925int elf_write_reloc(struct elf *elf, struct reloc *reloc)
926{
927 struct section *sec = reloc->sec;
928
929 if (sec->sh.sh_type == SHT_REL) {
930 reloc->rel.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);
931 reloc->rel.r_offset = reloc->offset;
932
933 if (!gelf_update_rel(sec->data, reloc->idx, &reloc->rel)) {
934 WARN_ELF("gelf_update_rel");
935 return -1;
936 }
937 } else {
938 reloc->rela.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);
939 reloc->rela.r_addend = reloc->addend;
940 reloc->rela.r_offset = reloc->offset;
941
942 if (!gelf_update_rela(sec->data, reloc->idx, &reloc->rela)) {
943 WARN_ELF("gelf_update_rela");
944 return -1;
945 }
946 }
947
948 elf->changed = true;
949
950 return 0;
951}
952
953int elf_write(struct elf *elf)
954{
955 struct section *sec;
956 Elf_Scn *s;
957
958 /* Update section headers for changed sections: */
959 list_for_each_entry(sec, &elf->sections, list) {
960 if (sec->changed) {
961 s = elf_getscn(elf->elf, sec->idx);
962 if (!s) {
963 WARN_ELF("elf_getscn");
964 return -1;
965 }
966 if (!gelf_update_shdr(s, &sec->sh)) {
967 WARN_ELF("gelf_update_shdr");
968 return -1;
969 }
970
971 sec->changed = false;
972 }
973 }
974
975 /* Make sure the new section header entries get updated properly. */
976 elf_flagelf(elf->elf, ELF_C_SET, ELF_F_DIRTY);
977
978 /* Write all changes to the file. */
979 if (elf_update(elf->elf, ELF_C_WRITE) < 0) {
980 WARN_ELF("elf_update");
981 return -1;
982 }
983
984 elf->changed = false;
985
986 return 0;
987}
988
989void elf_close(struct elf *elf)
990{
991 struct section *sec, *tmpsec;
992 struct symbol *sym, *tmpsym;
993 struct reloc *reloc, *tmpreloc;
994
995 if (elf->elf)
996 elf_end(elf->elf);
997
998 if (elf->fd > 0)
999 close(elf->fd);
1000
1001 list_for_each_entry_safe(sec, tmpsec, &elf->sections, list) {
1002 list_for_each_entry_safe(sym, tmpsym, &sec->symbol_list, list) {
1003 list_del(&sym->list);
1004 hash_del(&sym->hash);
1005 free(sym);
1006 }
1007 list_for_each_entry_safe(reloc, tmpreloc, &sec->reloc_list, list) {
1008 list_del(&reloc->list);
1009 hash_del(&reloc->hash);
1010 free(reloc);
1011 }
1012 list_del(&sec->list);
1013 free(sec);
1014 }
1015
1016 free(elf);
1017}
1/*
2 * elf.c - ELF access library
3 *
4 * Adapted from kpatch (https://github.com/dynup/kpatch):
5 * Copyright (C) 2013-2015 Josh Poimboeuf <jpoimboe@redhat.com>
6 * Copyright (C) 2014 Seth Jennings <sjenning@redhat.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version 2
11 * of the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, see <http://www.gnu.org/licenses/>.
20 */
21
22#include <sys/types.h>
23#include <sys/stat.h>
24#include <fcntl.h>
25#include <stdio.h>
26#include <stdlib.h>
27#include <string.h>
28#include <unistd.h>
29#include <errno.h>
30
31#include "elf.h"
32#include "warn.h"
33
34struct section *find_section_by_name(struct elf *elf, const char *name)
35{
36 struct section *sec;
37
38 list_for_each_entry(sec, &elf->sections, list)
39 if (!strcmp(sec->name, name))
40 return sec;
41
42 return NULL;
43}
44
45static struct section *find_section_by_index(struct elf *elf,
46 unsigned int idx)
47{
48 struct section *sec;
49
50 list_for_each_entry(sec, &elf->sections, list)
51 if (sec->idx == idx)
52 return sec;
53
54 return NULL;
55}
56
57static struct symbol *find_symbol_by_index(struct elf *elf, unsigned int idx)
58{
59 struct section *sec;
60 struct symbol *sym;
61
62 list_for_each_entry(sec, &elf->sections, list)
63 hash_for_each_possible(sec->symbol_hash, sym, hash, idx)
64 if (sym->idx == idx)
65 return sym;
66
67 return NULL;
68}
69
70struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset)
71{
72 struct symbol *sym;
73
74 list_for_each_entry(sym, &sec->symbol_list, list)
75 if (sym->type != STT_SECTION &&
76 sym->offset == offset)
77 return sym;
78
79 return NULL;
80}
81
82struct symbol *find_symbol_by_name(struct elf *elf, const char *name)
83{
84 struct section *sec;
85 struct symbol *sym;
86
87 list_for_each_entry(sec, &elf->sections, list)
88 list_for_each_entry(sym, &sec->symbol_list, list)
89 if (!strcmp(sym->name, name))
90 return sym;
91
92 return NULL;
93}
94
95struct symbol *find_symbol_containing(struct section *sec, unsigned long offset)
96{
97 struct symbol *sym;
98
99 list_for_each_entry(sym, &sec->symbol_list, list)
100 if (sym->type != STT_SECTION &&
101 offset >= sym->offset && offset < sym->offset + sym->len)
102 return sym;
103
104 return NULL;
105}
106
107struct rela *find_rela_by_dest_range(struct section *sec, unsigned long offset,
108 unsigned int len)
109{
110 struct rela *rela;
111 unsigned long o;
112
113 if (!sec->rela)
114 return NULL;
115
116 for (o = offset; o < offset + len; o++)
117 hash_for_each_possible(sec->rela->rela_hash, rela, hash, o)
118 if (rela->offset == o)
119 return rela;
120
121 return NULL;
122}
123
124struct rela *find_rela_by_dest(struct section *sec, unsigned long offset)
125{
126 return find_rela_by_dest_range(sec, offset, 1);
127}
128
129struct symbol *find_containing_func(struct section *sec, unsigned long offset)
130{
131 struct symbol *func;
132
133 list_for_each_entry(func, &sec->symbol_list, list)
134 if (func->type == STT_FUNC && offset >= func->offset &&
135 offset < func->offset + func->len)
136 return func;
137
138 return NULL;
139}
140
141static int read_sections(struct elf *elf)
142{
143 Elf_Scn *s = NULL;
144 struct section *sec;
145 size_t shstrndx, sections_nr;
146 int i;
147
148 if (elf_getshdrnum(elf->elf, §ions_nr)) {
149 WARN_ELF("elf_getshdrnum");
150 return -1;
151 }
152
153 if (elf_getshdrstrndx(elf->elf, &shstrndx)) {
154 WARN_ELF("elf_getshdrstrndx");
155 return -1;
156 }
157
158 for (i = 0; i < sections_nr; i++) {
159 sec = malloc(sizeof(*sec));
160 if (!sec) {
161 perror("malloc");
162 return -1;
163 }
164 memset(sec, 0, sizeof(*sec));
165
166 INIT_LIST_HEAD(&sec->symbol_list);
167 INIT_LIST_HEAD(&sec->rela_list);
168 hash_init(sec->rela_hash);
169 hash_init(sec->symbol_hash);
170
171 list_add_tail(&sec->list, &elf->sections);
172
173 s = elf_getscn(elf->elf, i);
174 if (!s) {
175 WARN_ELF("elf_getscn");
176 return -1;
177 }
178
179 sec->idx = elf_ndxscn(s);
180
181 if (!gelf_getshdr(s, &sec->sh)) {
182 WARN_ELF("gelf_getshdr");
183 return -1;
184 }
185
186 sec->name = elf_strptr(elf->elf, shstrndx, sec->sh.sh_name);
187 if (!sec->name) {
188 WARN_ELF("elf_strptr");
189 return -1;
190 }
191
192 if (sec->sh.sh_size != 0) {
193 sec->data = elf_getdata(s, NULL);
194 if (!sec->data) {
195 WARN_ELF("elf_getdata");
196 return -1;
197 }
198 if (sec->data->d_off != 0 ||
199 sec->data->d_size != sec->sh.sh_size) {
200 WARN("unexpected data attributes for %s",
201 sec->name);
202 return -1;
203 }
204 }
205 sec->len = sec->sh.sh_size;
206 }
207
208 /* sanity check, one more call to elf_nextscn() should return NULL */
209 if (elf_nextscn(elf->elf, s)) {
210 WARN("section entry mismatch");
211 return -1;
212 }
213
214 return 0;
215}
216
217static int read_symbols(struct elf *elf)
218{
219 struct section *symtab, *sec;
220 struct symbol *sym, *pfunc;
221 struct list_head *entry, *tmp;
222 int symbols_nr, i;
223 char *coldstr;
224
225 symtab = find_section_by_name(elf, ".symtab");
226 if (!symtab) {
227 WARN("missing symbol table");
228 return -1;
229 }
230
231 symbols_nr = symtab->sh.sh_size / symtab->sh.sh_entsize;
232
233 for (i = 0; i < symbols_nr; i++) {
234 sym = malloc(sizeof(*sym));
235 if (!sym) {
236 perror("malloc");
237 return -1;
238 }
239 memset(sym, 0, sizeof(*sym));
240
241 sym->idx = i;
242
243 if (!gelf_getsym(symtab->data, i, &sym->sym)) {
244 WARN_ELF("gelf_getsym");
245 goto err;
246 }
247
248 sym->name = elf_strptr(elf->elf, symtab->sh.sh_link,
249 sym->sym.st_name);
250 if (!sym->name) {
251 WARN_ELF("elf_strptr");
252 goto err;
253 }
254
255 sym->type = GELF_ST_TYPE(sym->sym.st_info);
256 sym->bind = GELF_ST_BIND(sym->sym.st_info);
257
258 if (sym->sym.st_shndx > SHN_UNDEF &&
259 sym->sym.st_shndx < SHN_LORESERVE) {
260 sym->sec = find_section_by_index(elf,
261 sym->sym.st_shndx);
262 if (!sym->sec) {
263 WARN("couldn't find section for symbol %s",
264 sym->name);
265 goto err;
266 }
267 if (sym->type == STT_SECTION) {
268 sym->name = sym->sec->name;
269 sym->sec->sym = sym;
270 }
271 } else
272 sym->sec = find_section_by_index(elf, 0);
273
274 sym->offset = sym->sym.st_value;
275 sym->len = sym->sym.st_size;
276
277 /* sorted insert into a per-section list */
278 entry = &sym->sec->symbol_list;
279 list_for_each_prev(tmp, &sym->sec->symbol_list) {
280 struct symbol *s;
281
282 s = list_entry(tmp, struct symbol, list);
283
284 if (sym->offset > s->offset) {
285 entry = tmp;
286 break;
287 }
288
289 if (sym->offset == s->offset && sym->len >= s->len) {
290 entry = tmp;
291 break;
292 }
293 }
294 list_add(&sym->list, entry);
295 hash_add(sym->sec->symbol_hash, &sym->hash, sym->idx);
296 }
297
298 /* Create parent/child links for any cold subfunctions */
299 list_for_each_entry(sec, &elf->sections, list) {
300 list_for_each_entry(sym, &sec->symbol_list, list) {
301 if (sym->type != STT_FUNC)
302 continue;
303 sym->pfunc = sym->cfunc = sym;
304 coldstr = strstr(sym->name, ".cold.");
305 if (coldstr) {
306 coldstr[0] = '\0';
307 pfunc = find_symbol_by_name(elf, sym->name);
308 coldstr[0] = '.';
309
310 if (!pfunc) {
311 WARN("%s(): can't find parent function",
312 sym->name);
313 goto err;
314 }
315
316 sym->pfunc = pfunc;
317 pfunc->cfunc = sym;
318 }
319 }
320 }
321
322 return 0;
323
324err:
325 free(sym);
326 return -1;
327}
328
329static int read_relas(struct elf *elf)
330{
331 struct section *sec;
332 struct rela *rela;
333 int i;
334 unsigned int symndx;
335
336 list_for_each_entry(sec, &elf->sections, list) {
337 if (sec->sh.sh_type != SHT_RELA)
338 continue;
339
340 sec->base = find_section_by_name(elf, sec->name + 5);
341 if (!sec->base) {
342 WARN("can't find base section for rela section %s",
343 sec->name);
344 return -1;
345 }
346
347 sec->base->rela = sec;
348
349 for (i = 0; i < sec->sh.sh_size / sec->sh.sh_entsize; i++) {
350 rela = malloc(sizeof(*rela));
351 if (!rela) {
352 perror("malloc");
353 return -1;
354 }
355 memset(rela, 0, sizeof(*rela));
356
357 if (!gelf_getrela(sec->data, i, &rela->rela)) {
358 WARN_ELF("gelf_getrela");
359 return -1;
360 }
361
362 rela->type = GELF_R_TYPE(rela->rela.r_info);
363 rela->addend = rela->rela.r_addend;
364 rela->offset = rela->rela.r_offset;
365 symndx = GELF_R_SYM(rela->rela.r_info);
366 rela->sym = find_symbol_by_index(elf, symndx);
367 if (!rela->sym) {
368 WARN("can't find rela entry symbol %d for %s",
369 symndx, sec->name);
370 return -1;
371 }
372
373 list_add_tail(&rela->list, &sec->rela_list);
374 hash_add(sec->rela_hash, &rela->hash, rela->offset);
375
376 }
377 }
378
379 return 0;
380}
381
382struct elf *elf_open(const char *name, int flags)
383{
384 struct elf *elf;
385 Elf_Cmd cmd;
386
387 elf_version(EV_CURRENT);
388
389 elf = malloc(sizeof(*elf));
390 if (!elf) {
391 perror("malloc");
392 return NULL;
393 }
394 memset(elf, 0, sizeof(*elf));
395
396 INIT_LIST_HEAD(&elf->sections);
397
398 elf->fd = open(name, flags);
399 if (elf->fd == -1) {
400 fprintf(stderr, "objtool: Can't open '%s': %s\n",
401 name, strerror(errno));
402 goto err;
403 }
404
405 if ((flags & O_ACCMODE) == O_RDONLY)
406 cmd = ELF_C_READ_MMAP;
407 else if ((flags & O_ACCMODE) == O_RDWR)
408 cmd = ELF_C_RDWR;
409 else /* O_WRONLY */
410 cmd = ELF_C_WRITE;
411
412 elf->elf = elf_begin(elf->fd, cmd, NULL);
413 if (!elf->elf) {
414 WARN_ELF("elf_begin");
415 goto err;
416 }
417
418 if (!gelf_getehdr(elf->elf, &elf->ehdr)) {
419 WARN_ELF("gelf_getehdr");
420 goto err;
421 }
422
423 if (read_sections(elf))
424 goto err;
425
426 if (read_symbols(elf))
427 goto err;
428
429 if (read_relas(elf))
430 goto err;
431
432 return elf;
433
434err:
435 elf_close(elf);
436 return NULL;
437}
438
439struct section *elf_create_section(struct elf *elf, const char *name,
440 size_t entsize, int nr)
441{
442 struct section *sec, *shstrtab;
443 size_t size = entsize * nr;
444 struct Elf_Scn *s;
445 Elf_Data *data;
446
447 sec = malloc(sizeof(*sec));
448 if (!sec) {
449 perror("malloc");
450 return NULL;
451 }
452 memset(sec, 0, sizeof(*sec));
453
454 INIT_LIST_HEAD(&sec->symbol_list);
455 INIT_LIST_HEAD(&sec->rela_list);
456 hash_init(sec->rela_hash);
457 hash_init(sec->symbol_hash);
458
459 list_add_tail(&sec->list, &elf->sections);
460
461 s = elf_newscn(elf->elf);
462 if (!s) {
463 WARN_ELF("elf_newscn");
464 return NULL;
465 }
466
467 sec->name = strdup(name);
468 if (!sec->name) {
469 perror("strdup");
470 return NULL;
471 }
472
473 sec->idx = elf_ndxscn(s);
474 sec->len = size;
475 sec->changed = true;
476
477 sec->data = elf_newdata(s);
478 if (!sec->data) {
479 WARN_ELF("elf_newdata");
480 return NULL;
481 }
482
483 sec->data->d_size = size;
484 sec->data->d_align = 1;
485
486 if (size) {
487 sec->data->d_buf = malloc(size);
488 if (!sec->data->d_buf) {
489 perror("malloc");
490 return NULL;
491 }
492 memset(sec->data->d_buf, 0, size);
493 }
494
495 if (!gelf_getshdr(s, &sec->sh)) {
496 WARN_ELF("gelf_getshdr");
497 return NULL;
498 }
499
500 sec->sh.sh_size = size;
501 sec->sh.sh_entsize = entsize;
502 sec->sh.sh_type = SHT_PROGBITS;
503 sec->sh.sh_addralign = 1;
504 sec->sh.sh_flags = SHF_ALLOC;
505
506
507 /* Add section name to .shstrtab */
508 shstrtab = find_section_by_name(elf, ".shstrtab");
509 if (!shstrtab) {
510 WARN("can't find .shstrtab section");
511 return NULL;
512 }
513
514 s = elf_getscn(elf->elf, shstrtab->idx);
515 if (!s) {
516 WARN_ELF("elf_getscn");
517 return NULL;
518 }
519
520 data = elf_newdata(s);
521 if (!data) {
522 WARN_ELF("elf_newdata");
523 return NULL;
524 }
525
526 data->d_buf = sec->name;
527 data->d_size = strlen(name) + 1;
528 data->d_align = 1;
529
530 sec->sh.sh_name = shstrtab->len;
531
532 shstrtab->len += strlen(name) + 1;
533 shstrtab->changed = true;
534
535 return sec;
536}
537
538struct section *elf_create_rela_section(struct elf *elf, struct section *base)
539{
540 char *relaname;
541 struct section *sec;
542
543 relaname = malloc(strlen(base->name) + strlen(".rela") + 1);
544 if (!relaname) {
545 perror("malloc");
546 return NULL;
547 }
548 strcpy(relaname, ".rela");
549 strcat(relaname, base->name);
550
551 sec = elf_create_section(elf, relaname, sizeof(GElf_Rela), 0);
552 free(relaname);
553 if (!sec)
554 return NULL;
555
556 base->rela = sec;
557 sec->base = base;
558
559 sec->sh.sh_type = SHT_RELA;
560 sec->sh.sh_addralign = 8;
561 sec->sh.sh_link = find_section_by_name(elf, ".symtab")->idx;
562 sec->sh.sh_info = base->idx;
563 sec->sh.sh_flags = SHF_INFO_LINK;
564
565 return sec;
566}
567
568int elf_rebuild_rela_section(struct section *sec)
569{
570 struct rela *rela;
571 int nr, idx = 0, size;
572 GElf_Rela *relas;
573
574 nr = 0;
575 list_for_each_entry(rela, &sec->rela_list, list)
576 nr++;
577
578 size = nr * sizeof(*relas);
579 relas = malloc(size);
580 if (!relas) {
581 perror("malloc");
582 return -1;
583 }
584
585 sec->data->d_buf = relas;
586 sec->data->d_size = size;
587
588 sec->sh.sh_size = size;
589
590 idx = 0;
591 list_for_each_entry(rela, &sec->rela_list, list) {
592 relas[idx].r_offset = rela->offset;
593 relas[idx].r_addend = rela->addend;
594 relas[idx].r_info = GELF_R_INFO(rela->sym->idx, rela->type);
595 idx++;
596 }
597
598 return 0;
599}
600
601int elf_write(struct elf *elf)
602{
603 struct section *sec;
604 Elf_Scn *s;
605
606 /* Update section headers for changed sections: */
607 list_for_each_entry(sec, &elf->sections, list) {
608 if (sec->changed) {
609 s = elf_getscn(elf->elf, sec->idx);
610 if (!s) {
611 WARN_ELF("elf_getscn");
612 return -1;
613 }
614 if (!gelf_update_shdr(s, &sec->sh)) {
615 WARN_ELF("gelf_update_shdr");
616 return -1;
617 }
618 }
619 }
620
621 /* Make sure the new section header entries get updated properly. */
622 elf_flagelf(elf->elf, ELF_C_SET, ELF_F_DIRTY);
623
624 /* Write all changes to the file. */
625 if (elf_update(elf->elf, ELF_C_WRITE) < 0) {
626 WARN_ELF("elf_update");
627 return -1;
628 }
629
630 return 0;
631}
632
633void elf_close(struct elf *elf)
634{
635 struct section *sec, *tmpsec;
636 struct symbol *sym, *tmpsym;
637 struct rela *rela, *tmprela;
638
639 if (elf->elf)
640 elf_end(elf->elf);
641
642 if (elf->fd > 0)
643 close(elf->fd);
644
645 list_for_each_entry_safe(sec, tmpsec, &elf->sections, list) {
646 list_for_each_entry_safe(sym, tmpsym, &sec->symbol_list, list) {
647 list_del(&sym->list);
648 hash_del(&sym->hash);
649 free(sym);
650 }
651 list_for_each_entry_safe(rela, tmprela, &sec->rela_list, list) {
652 list_del(&rela->list);
653 hash_del(&rela->hash);
654 free(rela);
655 }
656 list_del(&sec->list);
657 free(sec);
658 }
659
660 free(elf);
661}