Line data Source code
1 : /* Discard section not used at runtime from object files.
2 : Copyright (C) 2000-2012, 2014, 2015, 2016, 2017 Red Hat, Inc.
3 : This file is part of elfutils.
4 : Written by Ulrich Drepper <drepper@redhat.com>, 2000.
5 :
6 : This file is free software; you can redistribute it and/or modify
7 : it under the terms of the GNU General Public License as published by
8 : the Free Software Foundation; either version 3 of the License, or
9 : (at your option) any later version.
10 :
11 : elfutils is distributed in the hope that it will be useful, but
12 : WITHOUT ANY WARRANTY; without even the implied warranty of
13 : MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 : GNU General Public License for more details.
15 :
16 : You should have received a copy of the GNU General Public License
17 : along with this program. If not, see <http://www.gnu.org/licenses/>. */
18 :
19 : #ifdef HAVE_CONFIG_H
20 : # include <config.h>
21 : #endif
22 :
23 : #include <argp.h>
24 : #include <assert.h>
25 : #include <byteswap.h>
26 : #include <endian.h>
27 : #include <error.h>
28 : #include <fcntl.h>
29 : #include <fnmatch.h>
30 : #include <gelf.h>
31 : #include <libelf.h>
32 : #include <libintl.h>
33 : #include <locale.h>
34 : #include <stdbool.h>
35 : #include <stdio.h>
36 : #include <stdio_ext.h>
37 : #include <stdlib.h>
38 : #include <string.h>
39 : #include <unistd.h>
40 : #include <sys/stat.h>
41 : #include <sys/time.h>
42 :
43 : #include <elf-knowledge.h>
44 : #include <libebl.h>
45 : #include "libdwelf.h"
46 : #include <libeu.h>
47 : #include <system.h>
48 : #include <printversion.h>
49 :
50 : typedef uint8_t GElf_Byte;
51 :
52 : /* Name and version of program. */
53 : ARGP_PROGRAM_VERSION_HOOK_DEF = print_version;
54 :
55 : /* Bug report address. */
56 : ARGP_PROGRAM_BUG_ADDRESS_DEF = PACKAGE_BUGREPORT;
57 :
58 :
59 : /* Values for the parameters which have no short form. */
60 : #define OPT_REMOVE_COMMENT 0x100
61 : #define OPT_PERMISSIVE 0x101
62 : #define OPT_STRIP_SECTIONS 0x102
63 : #define OPT_RELOC_DEBUG 0x103
64 : #define OPT_KEEP_SECTION 0x104
65 :
66 :
67 : /* Definitions of arguments for argp functions. */
68 : static const struct argp_option options[] =
69 : {
70 : { NULL, 0, NULL, 0, N_("Output selection:"), 0 },
71 : { "output", 'o', "FILE", 0, N_("Place stripped output into FILE"), 0 },
72 : { NULL, 'f', "FILE", 0, N_("Extract the removed sections into FILE"), 0 },
73 : { NULL, 'F', "FILE", 0, N_("Embed name FILE instead of -f argument"), 0 },
74 :
75 : { NULL, 0, NULL, 0, N_("Output options:"), 0 },
76 : { "strip-all", 's', NULL, OPTION_HIDDEN, NULL, 0 },
77 : { "strip-debug", 'g', NULL, 0, N_("Remove all debugging symbols"), 0 },
78 : { NULL, 'd', NULL, OPTION_ALIAS, NULL, 0 },
79 : { NULL, 'S', NULL, OPTION_ALIAS, NULL, 0 },
80 : { "strip-sections", OPT_STRIP_SECTIONS, NULL, 0,
81 : N_("Remove section headers (not recommended)"), 0 },
82 : { "preserve-dates", 'p', NULL, 0,
83 : N_("Copy modified/access timestamps to the output"), 0 },
84 : { "reloc-debug-sections", OPT_RELOC_DEBUG, NULL, 0,
85 : N_("Resolve all trivial relocations between debug sections if the removed sections are placed in a debug file (only relevant for ET_REL files, operation is not reversable, needs -f)"), 0 },
86 : { "remove-comment", OPT_REMOVE_COMMENT, NULL, 0,
87 : N_("Remove .comment section"), 0 },
88 : { "remove-section", 'R', "SECTION", 0, N_("Remove the named section. SECTION is an extended wildcard pattern. May be given more than once. Only non-allocated sections can be removed."), 0 },
89 : { "keep-section", OPT_KEEP_SECTION, "SECTION", 0, N_("Keep the named section. SECTION is an extended wildcard pattern. May be given more than once."), 0 },
90 : { "permissive", OPT_PERMISSIVE, NULL, 0,
91 : N_("Relax a few rules to handle slightly broken ELF files"), 0 },
92 : { NULL, 0, NULL, 0, NULL, 0 }
93 : };
94 :
95 : /* Short description of program. */
96 : static const char doc[] = N_("Discard symbols from object files.");
97 :
98 : /* Strings for arguments in help texts. */
99 : static const char args_doc[] = N_("[FILE...]");
100 :
101 : /* Prototype for option handler. */
102 : static error_t parse_opt (int key, char *arg, struct argp_state *state);
103 :
104 : /* Data structure to communicate with argp functions. */
105 : static struct argp argp =
106 : {
107 : options, parse_opt, args_doc, doc, NULL, NULL, NULL
108 : };
109 :
110 :
111 : /* Print symbols in file named FNAME. */
112 : static int process_file (const char *fname);
113 :
114 : /* Handle one ELF file. */
115 : static int handle_elf (int fd, Elf *elf, const char *prefix,
116 : const char *fname, mode_t mode, struct timespec tvp[2]);
117 :
118 : /* Handle all files contained in the archive. */
119 : static int handle_ar (int fd, Elf *elf, const char *prefix, const char *fname,
120 : struct timespec tvp[2]) __attribute__ ((unused));
121 :
122 : static int debug_fd = -1;
123 : static char *tmp_debug_fname = NULL;
124 :
125 : /* Close debug file descriptor, if opened. And remove temporary debug file. */
126 : static void cleanup_debug (void);
127 :
128 : #define INTERNAL_ERROR(fname) \
129 : do { \
130 : cleanup_debug (); \
131 : error (EXIT_FAILURE, 0, gettext ("%s: INTERNAL ERROR %d (%s): %s"), \
132 : fname, __LINE__, PACKAGE_VERSION, elf_errmsg (-1)); \
133 : } while (0)
134 :
135 :
136 : /* Name of the output file. */
137 : static const char *output_fname;
138 :
139 : /* Name of the debug output file. */
140 : static const char *debug_fname;
141 :
142 : /* Name to pretend the debug output file has. */
143 : static const char *debug_fname_embed;
144 :
145 : /* If true output files shall have same date as the input file. */
146 : static bool preserve_dates;
147 :
148 : /* If true .comment sections will be removed. */
149 : static bool remove_comment;
150 :
151 : /* If true remove all debug sections. */
152 : static bool remove_debug;
153 :
154 : /* If true remove all section headers. */
155 : static bool remove_shdrs;
156 :
157 : /* If true relax some ELF rules for input files. */
158 : static bool permissive;
159 :
160 : /* If true perform relocations between debug sections. */
161 : static bool reloc_debug;
162 :
163 : /* Sections the user explicitly wants to keep or remove. */
164 : struct section_pattern
165 : {
166 : char *pattern;
167 : struct section_pattern *next;
168 : };
169 :
170 : static struct section_pattern *keep_secs = NULL;
171 : static struct section_pattern *remove_secs = NULL;
172 :
173 : static void
174 10 : add_pattern (struct section_pattern **patterns, const char *pattern)
175 : {
176 10 : struct section_pattern *p = xmalloc (sizeof *p);
177 10 : p->pattern = xstrdup (pattern);
178 10 : p->next = *patterns;
179 10 : *patterns = p;
180 10 : }
181 :
182 : static void
183 154 : free_sec_patterns (struct section_pattern *patterns)
184 : {
185 154 : struct section_pattern *pattern = patterns;
186 318 : while (pattern != NULL)
187 : {
188 10 : struct section_pattern *p = pattern;
189 10 : pattern = p->next;
190 10 : free (p->pattern);
191 10 : free (p);
192 : }
193 154 : }
194 :
195 : static void
196 77 : free_patterns (void)
197 : {
198 77 : free_sec_patterns (keep_secs);
199 77 : free_sec_patterns (remove_secs);
200 77 : }
201 :
202 : static bool
203 : section_name_matches (struct section_pattern *patterns, const char *name)
204 : {
205 4943 : struct section_pattern *pattern = patterns;
206 5194 : while (pattern != NULL)
207 : {
208 269 : if (fnmatch (pattern->pattern, name, FNM_EXTMATCH) == 0)
209 : return true;
210 251 : pattern = pattern->next;
211 : }
212 : return false;
213 : }
214 :
215 :
216 : int
217 77 : main (int argc, char *argv[])
218 : {
219 : int remaining;
220 77 : int result = 0;
221 :
222 : /* We use no threads here which can interfere with handling a stream. */
223 77 : __fsetlocking (stdin, FSETLOCKING_BYCALLER);
224 77 : __fsetlocking (stdout, FSETLOCKING_BYCALLER);
225 77 : __fsetlocking (stderr, FSETLOCKING_BYCALLER);
226 :
227 : /* Set locale. */
228 77 : setlocale (LC_ALL, "");
229 :
230 : /* Make sure the message catalog can be found. */
231 77 : bindtextdomain (PACKAGE_TARNAME, LOCALEDIR);
232 :
233 : /* Initialize the message catalog. */
234 77 : textdomain (PACKAGE_TARNAME);
235 :
236 : /* Parse and process arguments. */
237 77 : if (argp_parse (&argp, argc, argv, 0, &remaining, NULL) != 0)
238 : return EXIT_FAILURE;
239 :
240 77 : if (reloc_debug && debug_fname == NULL)
241 : error (EXIT_FAILURE, 0,
242 0 : gettext ("--reloc-debug-sections used without -f"));
243 :
244 : /* Tell the library which version we are expecting. */
245 77 : elf_version (EV_CURRENT);
246 :
247 77 : if (remaining == argc)
248 : /* The user didn't specify a name so we use a.out. */
249 5 : result = process_file ("a.out");
250 : else
251 : {
252 : /* If we have seen the '-o' or '-f' option there must be exactly one
253 : input file. */
254 72 : if ((output_fname != NULL || debug_fname != NULL)
255 60 : && remaining + 1 < argc)
256 0 : error (EXIT_FAILURE, 0, gettext ("\
257 : Only one input file allowed together with '-o' and '-f'"));
258 :
259 : /* Process all the remaining files. */
260 : do
261 72 : result |= process_file (argv[remaining]);
262 72 : while (++remaining < argc);
263 : }
264 :
265 77 : free_patterns ();
266 77 : return result;
267 : }
268 :
269 :
270 : /* Handle program arguments. */
271 : static error_t
272 544 : parse_opt (int key, char *arg, struct argp_state *state)
273 : {
274 544 : switch (key)
275 : {
276 45 : case 'f':
277 45 : if (debug_fname != NULL)
278 : {
279 0 : error (0, 0, gettext ("-f option specified twice"));
280 0 : return EINVAL;
281 : }
282 45 : debug_fname = arg;
283 45 : break;
284 :
285 6 : case 'F':
286 6 : if (debug_fname_embed != NULL)
287 : {
288 0 : error (0, 0, gettext ("-F option specified twice"));
289 0 : return EINVAL;
290 : }
291 6 : debug_fname_embed = arg;
292 6 : break;
293 :
294 63 : case 'o':
295 63 : if (output_fname != NULL)
296 : {
297 0 : error (0, 0, gettext ("-o option specified twice"));
298 0 : return EINVAL;
299 : }
300 63 : output_fname = arg;
301 63 : break;
302 :
303 0 : case 'p':
304 0 : preserve_dates = true;
305 0 : break;
306 :
307 11 : case OPT_RELOC_DEBUG:
308 11 : reloc_debug = true;
309 11 : break;
310 :
311 1 : case OPT_REMOVE_COMMENT:
312 1 : remove_comment = true;
313 1 : break;
314 :
315 4 : case 'R':
316 4 : if (fnmatch (arg, ".comment", FNM_EXTMATCH) == 0)
317 0 : remove_comment = true;
318 4 : add_pattern (&remove_secs, arg);
319 4 : break;
320 :
321 6 : case OPT_KEEP_SECTION:
322 6 : add_pattern (&keep_secs, arg);
323 6 : break;
324 :
325 23 : case 'g':
326 : case 'd':
327 : case 'S':
328 23 : remove_debug = true;
329 23 : break;
330 :
331 0 : case OPT_STRIP_SECTIONS:
332 0 : remove_shdrs = true;
333 0 : break;
334 :
335 0 : case OPT_PERMISSIVE:
336 0 : permissive = true;
337 0 : break;
338 :
339 : case 's': /* Ignored for compatibility. */
340 : break;
341 :
342 77 : case ARGP_KEY_SUCCESS:
343 77 : if (remove_comment == true
344 2 : && section_name_matches (keep_secs, ".comment"))
345 : {
346 0 : argp_error (state,
347 0 : gettext ("cannot both keep and remove .comment section"));
348 0 : return EINVAL;
349 : }
350 : break;
351 :
352 : default:
353 : return ARGP_ERR_UNKNOWN;
354 : }
355 : return 0;
356 : }
357 :
358 :
359 : static int
360 77 : process_file (const char *fname)
361 : {
362 : /* If we have to preserve the modify and access timestamps get them
363 : now. We cannot use fstat() after opening the file since the open
364 : would change the access time. */
365 : struct stat pre_st;
366 : struct timespec tv[2];
367 77 : again:
368 77 : if (preserve_dates)
369 : {
370 0 : if (stat (fname, &pre_st) != 0)
371 : {
372 0 : error (0, errno, gettext ("cannot stat input file '%s'"), fname);
373 0 : return 1;
374 : }
375 :
376 : /* If we have to preserve the timestamp, we need it in the
377 : format utimes() understands. */
378 0 : tv[0] = pre_st.st_atim;
379 0 : tv[1] = pre_st.st_mtim;
380 : }
381 :
382 : /* Open the file. */
383 154 : int fd = open (fname, output_fname == NULL ? O_RDWR : O_RDONLY);
384 77 : if (fd == -1)
385 : {
386 0 : error (0, errno, gettext ("while opening '%s'"), fname);
387 0 : return 1;
388 : }
389 :
390 : /* We always use fstat() even if we called stat() before. This is
391 : done to make sure the information returned by stat() is for the
392 : same file. */
393 : struct stat st;
394 77 : if (fstat (fd, &st) != 0)
395 : {
396 0 : error (0, errno, gettext ("cannot stat input file '%s'"), fname);
397 0 : return 1;
398 : }
399 : /* Paranoid mode on. */
400 77 : if (preserve_dates
401 0 : && (st.st_ino != pre_st.st_ino || st.st_dev != pre_st.st_dev))
402 : {
403 : /* We detected a race. Try again. */
404 0 : close (fd);
405 0 : goto again;
406 : }
407 :
408 : /* Now get the ELF descriptor. */
409 77 : Elf *elf = elf_begin (fd, output_fname == NULL ? ELF_C_RDWR : ELF_C_READ,
410 : NULL);
411 : int result;
412 77 : switch (elf_kind (elf))
413 : {
414 77 : case ELF_K_ELF:
415 77 : result = handle_elf (fd, elf, NULL, fname, st.st_mode & ACCESSPERMS,
416 77 : preserve_dates ? tv : NULL);
417 77 : break;
418 :
419 0 : case ELF_K_AR:
420 : /* It is not possible to strip the content of an archive direct
421 : the output to a specific file. */
422 0 : if (unlikely (output_fname != NULL || debug_fname != NULL))
423 : {
424 0 : error (0, 0, gettext ("%s: cannot use -o or -f when stripping archive"),
425 : fname);
426 0 : result = 1;
427 : }
428 : else
429 : {
430 : /* We would like to support ar archives, but currently it just
431 : doesn't work at all since we call elf_clone on the members
432 : which doesn't really support ar members.
433 : result = handle_ar (fd, elf, NULL, fname,
434 : preserve_dates ? tv : NULL);
435 : */
436 0 : error (0, 0, gettext ("%s: no support for stripping archive"),
437 : fname);
438 0 : result = 1;
439 : }
440 : break;
441 :
442 0 : default:
443 0 : error (0, 0, gettext ("%s: File format not recognized"), fname);
444 0 : result = 1;
445 0 : break;
446 : }
447 :
448 77 : if (unlikely (elf_end (elf) != 0))
449 0 : INTERNAL_ERROR (fname);
450 :
451 77 : close (fd);
452 :
453 77 : return result;
454 : }
455 :
456 :
457 : /* Maximum size of array allocated on stack. */
458 : #define MAX_STACK_ALLOC (400 * 1024)
459 :
460 : static int
461 77 : handle_elf (int fd, Elf *elf, const char *prefix, const char *fname,
462 : mode_t mode, struct timespec tvp[2])
463 : {
464 77 : size_t prefix_len = prefix == NULL ? 0 : strlen (prefix);
465 77 : size_t fname_len = strlen (fname) + 1;
466 77 : char *fullname = alloca (prefix_len + 1 + fname_len);
467 77 : char *cp = fullname;
468 77 : Elf *debugelf = NULL;
469 77 : tmp_debug_fname = NULL;
470 77 : int result = 0;
471 77 : size_t shdridx = 0;
472 : size_t shstrndx;
473 : struct shdr_info
474 : {
475 : Elf_Scn *scn;
476 : GElf_Shdr shdr;
477 : Elf_Data *data;
478 : Elf_Data *debug_data;
479 : const char *name;
480 : Elf32_Word idx; /* Index in new file. */
481 : Elf32_Word old_sh_link; /* Original value of shdr.sh_link. */
482 : Elf32_Word symtab_idx;
483 : Elf32_Word version_idx;
484 : Elf32_Word group_idx;
485 : Elf32_Word group_cnt;
486 : Elf_Scn *newscn;
487 : Dwelf_Strent *se;
488 : Elf32_Word *newsymidx;
489 77 : } *shdr_info = NULL;
490 : Elf_Scn *scn;
491 : size_t cnt;
492 : size_t idx;
493 : bool changes;
494 : GElf_Ehdr newehdr_mem;
495 : GElf_Ehdr *newehdr;
496 : GElf_Ehdr debugehdr_mem;
497 : GElf_Ehdr *debugehdr;
498 77 : Dwelf_Strtab *shst = NULL;
499 : Elf_Data debuglink_crc_data;
500 77 : bool any_symtab_changes = false;
501 77 : Elf_Data *shstrtab_data = NULL;
502 77 : void *debuglink_buf = NULL;
503 :
504 : /* Create the full name of the file. */
505 77 : if (prefix != NULL)
506 : {
507 0 : cp = mempcpy (cp, prefix, prefix_len);
508 0 : *cp++ = ':';
509 : }
510 154 : memcpy (cp, fname, fname_len);
511 :
512 : /* If we are not replacing the input file open a new file here. */
513 77 : if (output_fname != NULL)
514 : {
515 126 : fd = open (output_fname, O_RDWR | O_CREAT, mode);
516 63 : if (unlikely (fd == -1))
517 : {
518 0 : error (0, errno, gettext ("cannot open '%s'"), output_fname);
519 0 : return 1;
520 : }
521 : }
522 :
523 77 : debug_fd = -1;
524 :
525 : /* Get the EBL handling. Removing all debugging symbols with the -g
526 : option or resolving all relocations between debug sections with
527 : the --reloc-debug-sections option are currently the only reasons
528 : we need EBL so don't open the backend unless necessary. */
529 77 : Ebl *ebl = NULL;
530 77 : if (remove_debug || reloc_debug)
531 : {
532 34 : ebl = ebl_openbackend (elf);
533 34 : if (ebl == NULL)
534 : {
535 0 : error (0, errno, gettext ("cannot open EBL backend"));
536 0 : result = 1;
537 0 : goto fail;
538 : }
539 : }
540 :
541 : /* Open the additional file the debug information will be stored in. */
542 77 : if (debug_fname != NULL)
543 : {
544 : /* Create a temporary file name. We do not want to overwrite
545 : the debug file if the file would not contain any
546 : information. */
547 45 : size_t debug_fname_len = strlen (debug_fname);
548 45 : tmp_debug_fname = (char *) xmalloc (debug_fname_len + sizeof (".XXXXXX"));
549 135 : strcpy (mempcpy (tmp_debug_fname, debug_fname, debug_fname_len),
550 : ".XXXXXX");
551 :
552 45 : debug_fd = mkstemp (tmp_debug_fname);
553 45 : if (unlikely (debug_fd == -1))
554 : {
555 0 : error (0, errno, gettext ("cannot open '%s'"), debug_fname);
556 0 : result = 1;
557 0 : goto fail;
558 : }
559 : }
560 :
561 : /* Get the information from the old file. */
562 : GElf_Ehdr ehdr_mem;
563 77 : GElf_Ehdr *ehdr = gelf_getehdr (elf, &ehdr_mem);
564 77 : if (ehdr == NULL)
565 0 : INTERNAL_ERROR (fname);
566 :
567 : /* Get the section header string table index. */
568 77 : if (unlikely (elf_getshdrstrndx (elf, &shstrndx) < 0))
569 : {
570 0 : cleanup_debug ();
571 : error (EXIT_FAILURE, 0,
572 0 : gettext ("cannot get section header string table index"));
573 : }
574 :
575 : /* Get the number of phdrs in the old file. */
576 : size_t phnum;
577 77 : if (elf_getphdrnum (elf, &phnum) != 0)
578 : {
579 0 : cleanup_debug ();
580 0 : error (EXIT_FAILURE, 0, gettext ("cannot get number of phdrs"));
581 : }
582 :
583 : /* We now create a new ELF descriptor for the same file. We
584 : construct it almost exactly in the same way with some information
585 : dropped. */
586 : Elf *newelf;
587 77 : if (output_fname != NULL)
588 63 : newelf = elf_begin (fd, ELF_C_WRITE_MMAP, NULL);
589 : else
590 14 : newelf = elf_clone (elf, ELF_C_EMPTY);
591 :
592 77 : if (unlikely (gelf_newehdr (newelf, gelf_getclass (elf)) == 0)
593 77 : || (ehdr->e_type != ET_REL
594 46 : && unlikely (gelf_newphdr (newelf, phnum) == 0)))
595 : {
596 0 : error (0, 0, gettext ("cannot create new file '%s': %s"),
597 0 : output_fname ?: fname, elf_errmsg (-1));
598 : goto fail;
599 : }
600 :
601 : /* Copy over the old program header if needed. */
602 77 : if (ehdr->e_type != ET_REL)
603 373 : for (cnt = 0; cnt < phnum; ++cnt)
604 : {
605 : GElf_Phdr phdr_mem;
606 327 : GElf_Phdr *phdr = gelf_getphdr (elf, cnt, &phdr_mem);
607 327 : if (phdr == NULL
608 327 : || unlikely (gelf_update_phdr (newelf, cnt, phdr) == 0))
609 0 : INTERNAL_ERROR (fname);
610 : }
611 :
612 77 : if (debug_fname != NULL)
613 : {
614 : /* Also create an ELF descriptor for the debug file */
615 45 : debugelf = elf_begin (debug_fd, ELF_C_WRITE_MMAP, NULL);
616 45 : if (unlikely (gelf_newehdr (debugelf, gelf_getclass (elf)) == 0)
617 45 : || (ehdr->e_type != ET_REL
618 21 : && unlikely (gelf_newphdr (debugelf, phnum) == 0)))
619 : {
620 0 : error (0, 0, gettext ("cannot create new file '%s': %s"),
621 : debug_fname, elf_errmsg (-1));
622 : goto fail_close;
623 : }
624 :
625 : /* Copy over the old program header if needed. */
626 45 : if (ehdr->e_type != ET_REL)
627 171 : for (cnt = 0; cnt < phnum; ++cnt)
628 : {
629 : GElf_Phdr phdr_mem;
630 150 : GElf_Phdr *phdr = gelf_getphdr (elf, cnt, &phdr_mem);
631 150 : if (phdr == NULL
632 150 : || unlikely (gelf_update_phdr (debugelf, cnt, phdr) == 0))
633 0 : INTERNAL_ERROR (fname);
634 : }
635 : }
636 :
637 : /* Number of sections. */
638 : size_t shnum;
639 77 : if (unlikely (elf_getshdrnum (elf, &shnum) < 0))
640 : {
641 0 : error (0, 0, gettext ("cannot determine number of sections: %s"),
642 : elf_errmsg (-1));
643 : goto fail_close;
644 : }
645 :
646 77 : if (shstrndx >= shnum)
647 : goto illformed;
648 :
649 : #define elf_assert(test) do { if (!(test)) goto illformed; } while (0)
650 :
651 : /* Storage for section information. We leave room for two more
652 : entries since we unconditionally create a section header string
653 : table. Maybe some weird tool created an ELF file without one.
654 : The other one is used for the debug link section. */
655 77 : if ((shnum + 2) * sizeof (struct shdr_info) > MAX_STACK_ALLOC)
656 0 : shdr_info = (struct shdr_info *) xcalloc (shnum + 2,
657 : sizeof (struct shdr_info));
658 : else
659 : {
660 77 : shdr_info = (struct shdr_info *) alloca ((shnum + 2)
661 : * sizeof (struct shdr_info));
662 77 : memset (shdr_info, '\0', (shnum + 2) * sizeof (struct shdr_info));
663 : }
664 :
665 : /* Prepare section information data structure. */
666 77 : scn = NULL;
667 77 : cnt = 1;
668 2619 : while ((scn = elf_nextscn (elf, scn)) != NULL)
669 : {
670 : /* This should always be true (i.e., there should not be any
671 : holes in the numbering). */
672 2465 : elf_assert (elf_ndxscn (scn) == cnt);
673 :
674 2465 : shdr_info[cnt].scn = scn;
675 :
676 : /* Get the header. */
677 2465 : if (gelf_getshdr (scn, &shdr_info[cnt].shdr) == NULL)
678 0 : INTERNAL_ERROR (fname);
679 :
680 : /* Get the name of the section. */
681 2465 : shdr_info[cnt].name = elf_strptr (elf, shstrndx,
682 2465 : shdr_info[cnt].shdr.sh_name);
683 2465 : if (shdr_info[cnt].name == NULL)
684 : {
685 0 : illformed:
686 0 : error (0, 0, gettext ("illformed file '%s'"), fname);
687 : goto fail_close;
688 : }
689 :
690 : /* Sanity check the user. */
691 4930 : if (section_name_matches (remove_secs, shdr_info[cnt].name))
692 : {
693 6 : if ((shdr_info[cnt].shdr.sh_flags & SHF_ALLOC) != 0)
694 : {
695 0 : error (0, 0,
696 0 : gettext ("Cannot remove allocated section '%s'"),
697 : shdr_info[cnt].name);
698 0 : result = 1;
699 0 : goto fail_close;
700 : }
701 :
702 12 : if (section_name_matches (keep_secs, shdr_info[cnt].name))
703 : {
704 0 : error (0, 0,
705 0 : gettext ("Cannot both keep and remove section '%s'"),
706 0 : shdr_info[cnt].name);
707 0 : result = 1;
708 0 : goto fail_close;
709 : }
710 : }
711 :
712 : /* Mark them as present but not yet investigated. */
713 2465 : shdr_info[cnt].idx = 1;
714 :
715 : /* Remember the shdr.sh_link value. */
716 2465 : shdr_info[cnt].old_sh_link = shdr_info[cnt].shdr.sh_link;
717 2465 : if (shdr_info[cnt].old_sh_link >= shnum)
718 : goto illformed;
719 :
720 : /* Sections in files other than relocatable object files which
721 : not loaded can be freely moved by us. In theory we can also
722 : freely move around allocated nobits sections. But we don't
723 : to keep the layout of all allocated sections as similar as
724 : possible to the original file. In relocatable object files
725 : everything can be moved. */
726 2465 : if (ehdr->e_type == ET_REL
727 1519 : || (shdr_info[cnt].shdr.sh_flags & SHF_ALLOC) == 0)
728 1404 : shdr_info[cnt].shdr.sh_offset = 0;
729 :
730 : /* If this is an extended section index table store an
731 : appropriate reference. */
732 2465 : if (unlikely (shdr_info[cnt].shdr.sh_type == SHT_SYMTAB_SHNDX))
733 : {
734 0 : elf_assert (shdr_info[shdr_info[cnt].shdr.sh_link].symtab_idx == 0);
735 0 : shdr_info[shdr_info[cnt].shdr.sh_link].symtab_idx = cnt;
736 : }
737 2465 : else if (unlikely (shdr_info[cnt].shdr.sh_type == SHT_GROUP))
738 : {
739 : /* Cross-reference the sections contained in the section
740 : group. */
741 3 : shdr_info[cnt].data = elf_getdata (shdr_info[cnt].scn, NULL);
742 3 : if (shdr_info[cnt].data == NULL
743 3 : || shdr_info[cnt].data->d_size < sizeof (Elf32_Word))
744 0 : INTERNAL_ERROR (fname);
745 :
746 : /* XXX Fix for unaligned access. */
747 3 : Elf32_Word *grpref = (Elf32_Word *) shdr_info[cnt].data->d_buf;
748 : size_t inner;
749 9 : for (inner = 1;
750 6 : inner < shdr_info[cnt].data->d_size / sizeof (Elf32_Word);
751 3 : ++inner)
752 : {
753 3 : if (grpref[inner] < shnum)
754 3 : shdr_info[grpref[inner]].group_idx = cnt;
755 : else
756 : goto illformed;
757 : }
758 :
759 3 : if (inner == 1 || (inner == 2 && (grpref[0] & GRP_COMDAT) == 0))
760 : /* If the section group contains only one element and this
761 : is n COMDAT section we can drop it right away. */
762 0 : shdr_info[cnt].idx = 0;
763 : else
764 3 : shdr_info[cnt].group_cnt = inner - 1;
765 : }
766 2462 : else if (unlikely (shdr_info[cnt].shdr.sh_type == SHT_GNU_versym))
767 : {
768 46 : elf_assert (shdr_info[shdr_info[cnt].shdr.sh_link].version_idx == 0);
769 46 : shdr_info[shdr_info[cnt].shdr.sh_link].version_idx = cnt;
770 : }
771 :
772 : /* If this section is part of a group make sure it is not
773 : discarded right away. */
774 2465 : if ((shdr_info[cnt].shdr.sh_flags & SHF_GROUP) != 0)
775 : {
776 3 : elf_assert (shdr_info[cnt].group_idx != 0);
777 :
778 3 : if (shdr_info[shdr_info[cnt].group_idx].idx == 0)
779 : {
780 : /* The section group section will be removed. */
781 0 : shdr_info[cnt].group_idx = 0;
782 0 : shdr_info[cnt].shdr.sh_flags &= ~SHF_GROUP;
783 : }
784 : }
785 :
786 : /* Increment the counter. */
787 2465 : ++cnt;
788 : }
789 :
790 : /* Now determine which sections can go away. The general rule is that
791 : all sections which are not used at runtime are stripped out. But
792 : there are a few exceptions:
793 :
794 : - special sections named ".comment" and ".note" are kept
795 : - OS or architecture specific sections are kept since we might not
796 : know how to handle them
797 : - if a section is referred to from a section which is not removed
798 : in the sh_link or sh_info element it cannot be removed either
799 : - the user might have explicitly said to remove or keep a section
800 : */
801 2542 : for (cnt = 1; cnt < shnum; ++cnt)
802 : /* Check whether the section can be removed. Since we will create
803 : a new .shstrtab assume it will be removed too. */
804 4930 : if (remove_shdrs ? !(shdr_info[cnt].shdr.sh_flags & SHF_ALLOC)
805 4930 : : (ebl_section_strip_p (ebl, ehdr, &shdr_info[cnt].shdr,
806 2465 : shdr_info[cnt].name, remove_comment,
807 : remove_debug)
808 1511 : || cnt == ehdr->e_shstrndx
809 5441 : || section_name_matches (remove_secs, shdr_info[cnt].name)))
810 : {
811 : /* The user might want to explicitly keep this one. */
812 1966 : if (section_name_matches (keep_secs, shdr_info[cnt].name))
813 6 : continue;
814 :
815 : /* For now assume this section will be removed. */
816 977 : shdr_info[cnt].idx = 0;
817 :
818 977 : idx = shdr_info[cnt].group_idx;
819 1955 : while (idx != 0)
820 : {
821 : /* The section group data is already loaded. */
822 3 : elf_assert (shdr_info[idx].data != NULL
823 : && shdr_info[idx].data->d_buf != NULL
824 : && shdr_info[idx].data->d_size >= sizeof (Elf32_Word));
825 :
826 : /* If the references section group is a normal section
827 : group and has one element remaining, or if it is an
828 : empty COMDAT section group it is removed. */
829 2 : bool is_comdat = (((Elf32_Word *) shdr_info[idx].data->d_buf)[0]
830 1 : & GRP_COMDAT) != 0;
831 :
832 1 : --shdr_info[idx].group_cnt;
833 1 : if ((!is_comdat && shdr_info[idx].group_cnt == 1)
834 1 : || (is_comdat && shdr_info[idx].group_cnt == 0))
835 : {
836 1 : shdr_info[idx].idx = 0;
837 : /* Continue recursively. */
838 1 : idx = shdr_info[idx].group_idx;
839 : }
840 : else
841 : break;
842 : }
843 : }
844 :
845 : /* Mark the SHT_NULL section as handled. */
846 77 : shdr_info[0].idx = 2;
847 :
848 :
849 : /* Handle exceptions: section groups and cross-references. We might
850 : have to repeat this a few times since the resetting of the flag
851 : might propagate. */
852 : do
853 : {
854 77 : changes = false;
855 :
856 2542 : for (cnt = 1; cnt < shnum; ++cnt)
857 : {
858 2465 : if (shdr_info[cnt].idx == 0)
859 : {
860 : /* If a relocation section is marked as being removed make
861 : sure the section it is relocating is removed, too. */
862 1838 : if (shdr_info[cnt].shdr.sh_type == SHT_REL
863 919 : || shdr_info[cnt].shdr.sh_type == SHT_RELA)
864 : {
865 286 : if (shdr_info[cnt].shdr.sh_info >= shnum)
866 : goto illformed;
867 286 : else if (shdr_info[shdr_info[cnt].shdr.sh_info].idx != 0)
868 141 : shdr_info[cnt].idx = 1;
869 : }
870 :
871 : /* If a group section is marked as being removed make
872 : sure all the sections it contains are being removed, too. */
873 919 : if (shdr_info[cnt].shdr.sh_type == SHT_GROUP)
874 : {
875 : Elf32_Word *grpref;
876 3 : grpref = (Elf32_Word *) shdr_info[cnt].data->d_buf;
877 7 : for (size_t in = 1;
878 4 : in < shdr_info[cnt].data->d_size / sizeof (Elf32_Word);
879 1 : ++in)
880 3 : if (grpref[in] < shnum)
881 : {
882 3 : if (shdr_info[grpref[in]].idx != 0)
883 : {
884 2 : shdr_info[cnt].idx = 1;
885 2 : break;
886 : }
887 : }
888 : else
889 : goto illformed;
890 : }
891 : }
892 :
893 2465 : if (shdr_info[cnt].idx == 1)
894 : {
895 : /* The content of symbol tables we don't remove must not
896 : reference any section which we do remove. Otherwise
897 : we cannot remove the section. */
898 1689 : if (debug_fname != NULL
899 987 : && shdr_info[cnt].debug_data == NULL
900 1878 : && (shdr_info[cnt].shdr.sh_type == SHT_DYNSYM
901 939 : || shdr_info[cnt].shdr.sh_type == SHT_SYMTAB))
902 : {
903 : /* Make sure the data is loaded. */
904 28 : if (shdr_info[cnt].data == NULL)
905 : {
906 : shdr_info[cnt].data
907 28 : = elf_getdata (shdr_info[cnt].scn, NULL);
908 28 : if (shdr_info[cnt].data == NULL)
909 0 : INTERNAL_ERROR (fname);
910 : }
911 28 : Elf_Data *symdata = shdr_info[cnt].data;
912 :
913 : /* If there is an extended section index table load it
914 : as well. */
915 28 : if (shdr_info[cnt].symtab_idx != 0
916 0 : && shdr_info[shdr_info[cnt].symtab_idx].data == NULL)
917 : {
918 0 : elf_assert (shdr_info[cnt].shdr.sh_type == SHT_SYMTAB);
919 :
920 : shdr_info[shdr_info[cnt].symtab_idx].data
921 0 : = elf_getdata (shdr_info[shdr_info[cnt].symtab_idx].scn,
922 : NULL);
923 0 : if (shdr_info[shdr_info[cnt].symtab_idx].data == NULL)
924 0 : INTERNAL_ERROR (fname);
925 : }
926 28 : Elf_Data *xndxdata
927 28 : = shdr_info[shdr_info[cnt].symtab_idx].data;
928 :
929 : /* Go through all symbols and make sure the section they
930 : reference is not removed. */
931 28 : size_t elsize = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
932 :
933 1037 : for (size_t inner = 0;
934 1009 : inner < shdr_info[cnt].data->d_size / elsize;
935 981 : ++inner)
936 : {
937 : GElf_Sym sym_mem;
938 : Elf32_Word xndx;
939 981 : GElf_Sym *sym = gelf_getsymshndx (symdata, xndxdata,
940 : inner, &sym_mem,
941 : &xndx);
942 981 : if (sym == NULL)
943 0 : INTERNAL_ERROR (fname);
944 :
945 981 : size_t scnidx = sym->st_shndx;
946 981 : if (scnidx == SHN_UNDEF || scnidx >= shnum
947 531 : || (scnidx >= SHN_LORESERVE
948 : && scnidx <= SHN_HIRESERVE
949 531 : && scnidx != SHN_XINDEX)
950 : /* Don't count in the section symbols. */
951 531 : || GELF_ST_TYPE (sym->st_info) == STT_SECTION)
952 : /* This is no section index, leave it alone. */
953 668 : continue;
954 313 : else if (scnidx == SHN_XINDEX)
955 0 : scnidx = xndx;
956 :
957 313 : if (scnidx >= shnum)
958 : goto illformed;
959 :
960 313 : if (shdr_info[scnidx].idx == 0)
961 : /* This symbol table has a real symbol in
962 : a discarded section. So preserve the
963 : original table in the debug file. Unless
964 : it is a redundant data marker to a debug
965 : (data only) section. */
966 12 : if (! (ebl_section_strip_p (ebl, ehdr,
967 4 : &shdr_info[scnidx].shdr,
968 : shdr_info[scnidx].name,
969 : remove_comment,
970 : remove_debug)
971 4 : && ebl_data_marker_symbol (ebl, sym,
972 8 : elf_strptr (elf,
973 4 : shdr_info[cnt].shdr.sh_link,
974 4 : sym->st_name))))
975 0 : shdr_info[cnt].debug_data = symdata;
976 : }
977 : }
978 :
979 : /* Cross referencing happens:
980 : - for the cases the ELF specification says. That are
981 : + SHT_DYNAMIC in sh_link to string table
982 : + SHT_HASH in sh_link to symbol table
983 : + SHT_REL and SHT_RELA in sh_link to symbol table
984 : + SHT_SYMTAB and SHT_DYNSYM in sh_link to string table
985 : + SHT_GROUP in sh_link to symbol table
986 : + SHT_SYMTAB_SHNDX in sh_link to symbol table
987 : Other (OS or architecture-specific) sections might as
988 : well use this field so we process it unconditionally.
989 : - references inside section groups
990 : - specially marked references in sh_info if the SHF_INFO_LINK
991 : flag is set
992 : */
993 :
994 1689 : if (shdr_info[shdr_info[cnt].shdr.sh_link].idx == 0)
995 : {
996 58 : shdr_info[shdr_info[cnt].shdr.sh_link].idx = 1;
997 58 : changes |= shdr_info[cnt].shdr.sh_link < cnt;
998 : }
999 :
1000 : /* Handle references through sh_info. */
1001 1689 : if (SH_INFO_LINK_P (&shdr_info[cnt].shdr))
1002 : {
1003 232 : if (shdr_info[cnt].shdr.sh_info >= shnum)
1004 : goto illformed;
1005 232 : else if ( shdr_info[shdr_info[cnt].shdr.sh_info].idx == 0)
1006 : {
1007 0 : shdr_info[shdr_info[cnt].shdr.sh_info].idx = 1;
1008 0 : changes |= shdr_info[cnt].shdr.sh_info < cnt;
1009 : }
1010 : }
1011 :
1012 : /* Mark the section as investigated. */
1013 1689 : shdr_info[cnt].idx = 2;
1014 : }
1015 :
1016 2465 : if (debug_fname != NULL
1017 1446 : && (shdr_info[cnt].idx == 0 || shdr_info[cnt].debug_data != NULL))
1018 : {
1019 : /* This section is being preserved in the debug file.
1020 : Sections it refers to must be preserved there too.
1021 :
1022 : In this pass we mark sections to be preserved in both
1023 : files by setting the .debug_data pointer to the original
1024 : file's .data pointer. Below, we'll copy the section
1025 : contents. */
1026 :
1027 617 : inline void check_preserved (size_t i)
1028 : {
1029 617 : if (i != 0 && i < shnum + 2 && shdr_info[i].idx != 0
1030 137 : && shdr_info[i].debug_data == NULL)
1031 : {
1032 48 : if (shdr_info[i].data == NULL)
1033 48 : shdr_info[i].data = elf_getdata (shdr_info[i].scn, NULL);
1034 48 : if (shdr_info[i].data == NULL)
1035 0 : INTERNAL_ERROR (fname);
1036 :
1037 48 : shdr_info[i].debug_data = shdr_info[i].data;
1038 48 : changes |= i < cnt;
1039 : }
1040 617 : }
1041 :
1042 507 : check_preserved (shdr_info[cnt].shdr.sh_link);
1043 507 : if (SH_INFO_LINK_P (&shdr_info[cnt].shdr))
1044 110 : check_preserved (shdr_info[cnt].shdr.sh_info);
1045 : }
1046 : }
1047 : }
1048 77 : while (changes);
1049 :
1050 : /* Copy the removed sections to the debug output file.
1051 : The ones that are not removed in the stripped file are SHT_NOBITS. */
1052 77 : if (debug_fname != NULL)
1053 : {
1054 1491 : for (cnt = 1; cnt < shnum; ++cnt)
1055 : {
1056 1446 : scn = elf_newscn (debugelf);
1057 1446 : if (scn == NULL)
1058 : {
1059 0 : cleanup_debug ();
1060 0 : error (EXIT_FAILURE, 0,
1061 0 : gettext ("while generating output file: %s"),
1062 : elf_errmsg (-1));
1063 : }
1064 :
1065 2892 : bool discard_section = (shdr_info[cnt].idx > 0
1066 987 : && shdr_info[cnt].debug_data == NULL
1067 939 : && shdr_info[cnt].shdr.sh_type != SHT_NOTE
1068 891 : && shdr_info[cnt].shdr.sh_type != SHT_GROUP
1069 2335 : && cnt != ehdr->e_shstrndx);
1070 :
1071 : /* Set the section header in the new file. */
1072 1446 : GElf_Shdr debugshdr = shdr_info[cnt].shdr;
1073 1446 : if (discard_section)
1074 889 : debugshdr.sh_type = SHT_NOBITS;
1075 :
1076 1446 : if (unlikely (gelf_update_shdr (scn, &debugshdr) == 0))
1077 : /* There cannot be any overflows. */
1078 0 : INTERNAL_ERROR (fname);
1079 :
1080 : /* Get the data from the old file if necessary. */
1081 1446 : if (shdr_info[cnt].data == NULL)
1082 : {
1083 1367 : shdr_info[cnt].data = elf_getdata (shdr_info[cnt].scn, NULL);
1084 1367 : if (shdr_info[cnt].data == NULL)
1085 0 : INTERNAL_ERROR (fname);
1086 : }
1087 :
1088 : /* Set the data. This is done by copying from the old file. */
1089 1446 : Elf_Data *debugdata = elf_newdata (scn);
1090 1446 : if (debugdata == NULL)
1091 0 : INTERNAL_ERROR (fname);
1092 :
1093 : /* Copy the structure. This data may be modified in place
1094 : before we write out the file. */
1095 1446 : *debugdata = *shdr_info[cnt].data;
1096 1446 : if (discard_section)
1097 889 : debugdata->d_buf = NULL;
1098 557 : else if (shdr_info[cnt].debug_data != NULL
1099 509 : || shdr_info[cnt].shdr.sh_type == SHT_GROUP)
1100 : {
1101 : /* Copy the original data before it gets modified. */
1102 51 : shdr_info[cnt].debug_data = debugdata;
1103 51 : if (debugdata->d_buf == NULL)
1104 0 : INTERNAL_ERROR (fname);
1105 102 : debugdata->d_buf = memcpy (xmalloc (debugdata->d_size),
1106 : debugdata->d_buf, debugdata->d_size);
1107 : }
1108 : }
1109 :
1110 : /* Finish the ELF header. Fill in the fields not handled by
1111 : libelf from the old file. */
1112 45 : debugehdr = gelf_getehdr (debugelf, &debugehdr_mem);
1113 45 : if (debugehdr == NULL)
1114 0 : INTERNAL_ERROR (fname);
1115 :
1116 90 : memcpy (debugehdr->e_ident, ehdr->e_ident, EI_NIDENT);
1117 45 : debugehdr->e_type = ehdr->e_type;
1118 45 : debugehdr->e_machine = ehdr->e_machine;
1119 45 : debugehdr->e_version = ehdr->e_version;
1120 45 : debugehdr->e_entry = ehdr->e_entry;
1121 45 : debugehdr->e_flags = ehdr->e_flags;
1122 45 : debugehdr->e_shstrndx = ehdr->e_shstrndx;
1123 :
1124 45 : if (unlikely (gelf_update_ehdr (debugelf, debugehdr) == 0))
1125 : {
1126 0 : error (0, 0, gettext ("%s: error while creating ELF header: %s"),
1127 : debug_fname, elf_errmsg (-1));
1128 0 : result = 1;
1129 0 : goto fail_close;
1130 : }
1131 : }
1132 :
1133 : /* Although we always create a new section header string table we
1134 : don't explicitly mark the existing one as unused. It can still
1135 : be used through a symbol table section we are keeping. If not it
1136 : will already be marked as unused. */
1137 :
1138 : /* We need a string table for the section headers. */
1139 77 : shst = dwelf_strtab_init (true);
1140 77 : if (shst == NULL)
1141 : {
1142 0 : cleanup_debug ();
1143 0 : error (EXIT_FAILURE, errno, gettext ("while preparing output for '%s'"),
1144 0 : output_fname ?: fname);
1145 : }
1146 :
1147 : /* Assign new section numbers. */
1148 77 : shdr_info[0].idx = 0;
1149 2542 : for (cnt = idx = 1; cnt < shnum; ++cnt)
1150 2465 : if (shdr_info[cnt].idx > 0)
1151 : {
1152 1689 : shdr_info[cnt].idx = idx++;
1153 :
1154 : /* Create a new section. */
1155 1689 : shdr_info[cnt].newscn = elf_newscn (newelf);
1156 1689 : if (shdr_info[cnt].newscn == NULL)
1157 : {
1158 0 : cleanup_debug ();
1159 0 : error (EXIT_FAILURE, 0,
1160 0 : gettext ("while generating output file: %s"),
1161 : elf_errmsg (-1));
1162 : }
1163 :
1164 1689 : elf_assert (elf_ndxscn (shdr_info[cnt].newscn) == shdr_info[cnt].idx);
1165 :
1166 : /* Add this name to the section header string table. */
1167 1689 : shdr_info[cnt].se = dwelf_strtab_add (shst, shdr_info[cnt].name);
1168 : }
1169 :
1170 : /* Test whether we are doing anything at all. Either all removable
1171 : sections are already gone. Or the only section we would remove is
1172 : the .shstrtab section which we would add again. */
1173 231 : bool removing_sections = !(cnt == idx
1174 77 : || (cnt == idx + 1
1175 6 : && shdr_info[ehdr->e_shstrndx].idx == 0));
1176 77 : if (output_fname == NULL && !removing_sections)
1177 : goto fail_close;
1178 :
1179 : /* Create the reference to the file with the debug info (if any). */
1180 75 : if (debug_fname != NULL && !remove_shdrs && removing_sections)
1181 : {
1182 : /* Add the section header string table section name. */
1183 41 : shdr_info[cnt].se = dwelf_strtab_add_len (shst, ".gnu_debuglink", 15);
1184 41 : shdr_info[cnt].idx = idx++;
1185 :
1186 : /* Create the section header. */
1187 41 : shdr_info[cnt].shdr.sh_type = SHT_PROGBITS;
1188 41 : shdr_info[cnt].shdr.sh_flags = 0;
1189 41 : shdr_info[cnt].shdr.sh_addr = 0;
1190 41 : shdr_info[cnt].shdr.sh_link = SHN_UNDEF;
1191 41 : shdr_info[cnt].shdr.sh_info = SHN_UNDEF;
1192 41 : shdr_info[cnt].shdr.sh_entsize = 0;
1193 41 : shdr_info[cnt].shdr.sh_addralign = 4;
1194 : /* We set the offset to zero here. Before we write the ELF file the
1195 : field must have the correct value. This is done in the final
1196 : loop over all section. Then we have all the information needed. */
1197 41 : shdr_info[cnt].shdr.sh_offset = 0;
1198 :
1199 : /* Create the section. */
1200 41 : shdr_info[cnt].newscn = elf_newscn (newelf);
1201 41 : if (shdr_info[cnt].newscn == NULL)
1202 : {
1203 0 : cleanup_debug ();
1204 0 : error (EXIT_FAILURE, 0,
1205 0 : gettext ("while create section header section: %s"),
1206 : elf_errmsg (-1));
1207 : }
1208 41 : elf_assert (elf_ndxscn (shdr_info[cnt].newscn) == shdr_info[cnt].idx);
1209 :
1210 41 : shdr_info[cnt].data = elf_newdata (shdr_info[cnt].newscn);
1211 41 : if (shdr_info[cnt].data == NULL)
1212 : {
1213 0 : cleanup_debug ();
1214 0 : error (EXIT_FAILURE, 0, gettext ("cannot allocate section data: %s"),
1215 : elf_errmsg (-1));
1216 : }
1217 :
1218 41 : char *debug_basename = basename (debug_fname_embed ?: debug_fname);
1219 41 : off_t crc_offset = strlen (debug_basename) + 1;
1220 : /* Align to 4 byte boundary */
1221 41 : crc_offset = ((crc_offset - 1) & ~3) + 4;
1222 :
1223 41 : shdr_info[cnt].data->d_align = 4;
1224 41 : shdr_info[cnt].shdr.sh_size = shdr_info[cnt].data->d_size
1225 41 : = crc_offset + 4;
1226 41 : debuglink_buf = xcalloc (1, shdr_info[cnt].data->d_size);
1227 41 : shdr_info[cnt].data->d_buf = debuglink_buf;
1228 :
1229 82 : strcpy (shdr_info[cnt].data->d_buf, debug_basename);
1230 :
1231 : /* Cache this Elf_Data describing the CRC32 word in the section.
1232 : We'll fill this in when we have written the debug file. */
1233 41 : debuglink_crc_data = *shdr_info[cnt].data;
1234 82 : debuglink_crc_data.d_buf = ((char *) debuglink_crc_data.d_buf
1235 41 : + crc_offset);
1236 41 : debuglink_crc_data.d_size = 4;
1237 :
1238 : /* One more section done. */
1239 41 : ++cnt;
1240 : }
1241 :
1242 : /* Index of the section header table in the shdr_info array. */
1243 75 : shdridx = cnt;
1244 :
1245 : /* Add the section header string table section name. */
1246 75 : shdr_info[cnt].se = dwelf_strtab_add_len (shst, ".shstrtab", 10);
1247 75 : shdr_info[cnt].idx = idx;
1248 :
1249 : /* Create the section header. */
1250 75 : shdr_info[cnt].shdr.sh_type = SHT_STRTAB;
1251 75 : shdr_info[cnt].shdr.sh_flags = 0;
1252 75 : shdr_info[cnt].shdr.sh_addr = 0;
1253 75 : shdr_info[cnt].shdr.sh_link = SHN_UNDEF;
1254 75 : shdr_info[cnt].shdr.sh_info = SHN_UNDEF;
1255 75 : shdr_info[cnt].shdr.sh_entsize = 0;
1256 : /* We set the offset to zero here. Before we write the ELF file the
1257 : field must have the correct value. This is done in the final
1258 : loop over all section. Then we have all the information needed. */
1259 75 : shdr_info[cnt].shdr.sh_offset = 0;
1260 75 : shdr_info[cnt].shdr.sh_addralign = 1;
1261 :
1262 : /* Create the section. */
1263 75 : shdr_info[cnt].newscn = elf_newscn (newelf);
1264 75 : if (shdr_info[cnt].newscn == NULL)
1265 : {
1266 0 : cleanup_debug ();
1267 0 : error (EXIT_FAILURE, 0,
1268 0 : gettext ("while create section header section: %s"),
1269 : elf_errmsg (-1));
1270 : }
1271 75 : elf_assert (elf_ndxscn (shdr_info[cnt].newscn) == idx);
1272 :
1273 : /* Finalize the string table and fill in the correct indices in the
1274 : section headers. */
1275 75 : shstrtab_data = elf_newdata (shdr_info[cnt].newscn);
1276 75 : if (shstrtab_data == NULL)
1277 : {
1278 0 : cleanup_debug ();
1279 0 : error (EXIT_FAILURE, 0,
1280 0 : gettext ("while create section header string table: %s"),
1281 : elf_errmsg (-1));
1282 : }
1283 75 : if (dwelf_strtab_finalize (shst, shstrtab_data) == NULL)
1284 : {
1285 0 : cleanup_debug ();
1286 : error (EXIT_FAILURE, 0,
1287 0 : gettext ("no memory to create section header string table"));
1288 : }
1289 :
1290 : /* We have to set the section size. */
1291 75 : shdr_info[cnt].shdr.sh_size = shstrtab_data->d_size;
1292 :
1293 : /* Update the section information. */
1294 75 : GElf_Off lastoffset = 0;
1295 2604 : for (cnt = 1; cnt <= shdridx; ++cnt)
1296 2529 : if (shdr_info[cnt].idx > 0)
1297 : {
1298 : Elf_Data *newdata;
1299 :
1300 1755 : scn = elf_getscn (newelf, shdr_info[cnt].idx);
1301 1755 : elf_assert (scn != NULL);
1302 :
1303 : /* Update the name. */
1304 1755 : shdr_info[cnt].shdr.sh_name = dwelf_strent_off (shdr_info[cnt].se);
1305 :
1306 : /* Update the section header from the input file. Some fields
1307 : might be section indeces which now have to be adjusted. Keep
1308 : the index to the "current" sh_link in case we need it to lookup
1309 : symbol table names. */
1310 1755 : size_t sh_link = shdr_info[cnt].shdr.sh_link;
1311 1755 : if (shdr_info[cnt].shdr.sh_link != 0)
1312 502 : shdr_info[cnt].shdr.sh_link =
1313 502 : shdr_info[shdr_info[cnt].shdr.sh_link].idx;
1314 :
1315 1755 : if (shdr_info[cnt].shdr.sh_type == SHT_GROUP)
1316 : {
1317 4 : elf_assert (shdr_info[cnt].data != NULL
1318 : && shdr_info[cnt].data->d_buf != NULL);
1319 :
1320 : Elf32_Word *grpref = (Elf32_Word *) shdr_info[cnt].data->d_buf;
1321 6 : for (size_t inner = 0;
1322 6 : inner < shdr_info[cnt].data->d_size / sizeof (Elf32_Word);
1323 4 : ++inner)
1324 4 : if (grpref[inner] < shnum)
1325 4 : grpref[inner] = shdr_info[grpref[inner]].idx;
1326 : else
1327 : goto illformed;
1328 : }
1329 :
1330 : /* Handle the SHT_REL, SHT_RELA, and SHF_INFO_LINK flag. */
1331 1755 : if (SH_INFO_LINK_P (&shdr_info[cnt].shdr))
1332 230 : shdr_info[cnt].shdr.sh_info =
1333 230 : shdr_info[shdr_info[cnt].shdr.sh_info].idx;
1334 :
1335 : /* Get the data from the old file if necessary. We already
1336 : created the data for the section header string table. */
1337 1755 : if (cnt < shnum)
1338 : {
1339 1639 : if (shdr_info[cnt].data == NULL)
1340 : {
1341 677 : shdr_info[cnt].data = elf_getdata (shdr_info[cnt].scn, NULL);
1342 677 : if (shdr_info[cnt].data == NULL)
1343 0 : INTERNAL_ERROR (fname);
1344 : }
1345 :
1346 : /* Set the data. This is done by copying from the old file. */
1347 1639 : newdata = elf_newdata (scn);
1348 1639 : if (newdata == NULL)
1349 0 : INTERNAL_ERROR (fname);
1350 :
1351 : /* Copy the structure. */
1352 1639 : *newdata = *shdr_info[cnt].data;
1353 :
1354 : /* We know the size. */
1355 1639 : shdr_info[cnt].shdr.sh_size = shdr_info[cnt].data->d_size;
1356 :
1357 : /* We have to adjust symbol tables. The st_shndx member might
1358 : have to be updated. */
1359 3278 : if (shdr_info[cnt].shdr.sh_type == SHT_DYNSYM
1360 1639 : || shdr_info[cnt].shdr.sh_type == SHT_SYMTAB)
1361 : {
1362 89 : Elf_Data *versiondata = NULL;
1363 89 : Elf_Data *shndxdata = NULL;
1364 :
1365 89 : size_t elsize = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
1366 :
1367 89 : if (shdr_info[cnt].symtab_idx != 0)
1368 : {
1369 0 : elf_assert (shdr_info[cnt].shdr.sh_type == SHT_SYMTAB_SHNDX);
1370 : /* This section has extended section information.
1371 : We have to modify that information, too. */
1372 0 : shndxdata = elf_getdata (shdr_info[shdr_info[cnt].symtab_idx].scn,
1373 : NULL);
1374 :
1375 0 : elf_assert (shndxdata != NULL
1376 : && shndxdata->d_buf != NULL
1377 : && ((shndxdata->d_size / sizeof (Elf32_Word))
1378 : >= shdr_info[cnt].data->d_size / elsize));
1379 : }
1380 :
1381 89 : if (shdr_info[cnt].version_idx != 0)
1382 : {
1383 44 : elf_assert (shdr_info[cnt].shdr.sh_type == SHT_DYNSYM);
1384 : /* This section has associated version
1385 : information. We have to modify that
1386 : information, too. */
1387 44 : versiondata = elf_getdata (shdr_info[shdr_info[cnt].version_idx].scn,
1388 : NULL);
1389 :
1390 132 : elf_assert (versiondata != NULL
1391 : && versiondata->d_buf != NULL
1392 : && ((versiondata->d_size / sizeof (GElf_Versym))
1393 : >= shdr_info[cnt].data->d_size / elsize));
1394 : }
1395 :
1396 : shdr_info[cnt].newsymidx
1397 89 : = (Elf32_Word *) xcalloc (shdr_info[cnt].data->d_size
1398 : / elsize, sizeof (Elf32_Word));
1399 :
1400 89 : bool last_was_local = true;
1401 : size_t destidx;
1402 : size_t inner;
1403 15052 : for (destidx = inner = 1;
1404 14963 : inner < shdr_info[cnt].data->d_size / elsize;
1405 14874 : ++inner)
1406 : {
1407 : Elf32_Word sec;
1408 : GElf_Sym sym_mem;
1409 : Elf32_Word xshndx;
1410 14874 : GElf_Sym *sym = gelf_getsymshndx (shdr_info[cnt].data,
1411 : shndxdata, inner,
1412 : &sym_mem, &xshndx);
1413 14874 : if (sym == NULL)
1414 0 : INTERNAL_ERROR (fname);
1415 :
1416 14874 : if (sym->st_shndx == SHN_UNDEF
1417 13304 : || (sym->st_shndx >= shnum
1418 247 : && sym->st_shndx != SHN_XINDEX))
1419 : {
1420 : /* This is no section index, leave it alone
1421 : unless it is moved. */
1422 1817 : if (destidx != inner
1423 1345 : && gelf_update_symshndx (shdr_info[cnt].data,
1424 : shndxdata,
1425 : destidx, sym,
1426 : xshndx) == 0)
1427 0 : INTERNAL_ERROR (fname);
1428 :
1429 1817 : shdr_info[cnt].newsymidx[inner] = destidx++;
1430 :
1431 1817 : if (last_was_local
1432 226 : && GELF_ST_BIND (sym->st_info) != STB_LOCAL)
1433 : {
1434 53 : last_was_local = false;
1435 53 : shdr_info[cnt].shdr.sh_info = destidx - 1;
1436 : }
1437 :
1438 1817 : continue;
1439 : }
1440 :
1441 : /* Get the full section index, if necessary from the
1442 : XINDEX table. */
1443 13057 : if (sym->st_shndx == SHN_XINDEX)
1444 0 : elf_assert (shndxdata != NULL
1445 : && shndxdata->d_buf != NULL);
1446 13057 : size_t sidx = (sym->st_shndx != SHN_XINDEX
1447 13057 : ? sym->st_shndx : xshndx);
1448 13057 : sec = shdr_info[sidx].idx;
1449 :
1450 13057 : if (sec != 0)
1451 : {
1452 : GElf_Section nshndx;
1453 : Elf32_Word nxshndx;
1454 :
1455 2404 : if (sec < SHN_LORESERVE)
1456 : {
1457 2404 : nshndx = sec;
1458 2404 : nxshndx = 0;
1459 : }
1460 : else
1461 : {
1462 : nshndx = SHN_XINDEX;
1463 : nxshndx = sec;
1464 : }
1465 :
1466 2404 : elf_assert (sec < SHN_LORESERVE || shndxdata != NULL);
1467 :
1468 2404 : if ((inner != destidx || nshndx != sym->st_shndx
1469 1261 : || (shndxdata != NULL && nxshndx != xshndx))
1470 2286 : && (sym->st_shndx = nshndx,
1471 1143 : gelf_update_symshndx (shdr_info[cnt].data,
1472 : shndxdata,
1473 : destidx, sym,
1474 : nxshndx) == 0))
1475 0 : INTERNAL_ERROR (fname);
1476 :
1477 2404 : shdr_info[cnt].newsymidx[inner] = destidx++;
1478 :
1479 2404 : if (last_was_local
1480 1998 : && GELF_ST_BIND (sym->st_info) != STB_LOCAL)
1481 : {
1482 36 : last_was_local = false;
1483 36 : shdr_info[cnt].shdr.sh_info = destidx - 1;
1484 : }
1485 : }
1486 10653 : else if ((shdr_info[cnt].shdr.sh_flags & SHF_ALLOC) != 0
1487 48 : && GELF_ST_TYPE (sym->st_info) != STT_SECTION
1488 0 : && shdr_info[sidx].shdr.sh_type != SHT_GROUP)
1489 : {
1490 : /* Removing a real symbol from an allocated
1491 : symbol table is hard and probably a
1492 : mistake. Really removing it means
1493 : rewriting the dynamic segment and hash
1494 : sections. Just warn and set the symbol
1495 : section to UNDEF. */
1496 0 : error (0, 0,
1497 0 : gettext ("Cannot remove symbol [%zd] from allocated symbol table [%zd]"), inner, cnt);
1498 0 : sym->st_shndx = SHN_UNDEF;
1499 0 : if (gelf_update_sym (shdr_info[cnt].data, destidx,
1500 : sym) == 0)
1501 0 : INTERNAL_ERROR (fname);
1502 0 : shdr_info[cnt].newsymidx[inner] = destidx++;
1503 : }
1504 10653 : else if (debug_fname != NULL
1505 10481 : && shdr_info[cnt].debug_data == NULL)
1506 : /* The symbol points to a section that is discarded
1507 : but isn't preserved in the debug file. Check that
1508 : this is a section or group signature symbol
1509 : for a section which has been removed. Or a special
1510 : data marker symbol to a debug section. */
1511 : {
1512 43 : elf_assert (GELF_ST_TYPE (sym->st_info) == STT_SECTION
1513 : || ((shdr_info[sidx].shdr.sh_type
1514 : == SHT_GROUP)
1515 : && (shdr_info[sidx].shdr.sh_info
1516 : == inner))
1517 : || ebl_data_marker_symbol (ebl, sym,
1518 : elf_strptr (elf, sh_link,
1519 : sym->st_name)));
1520 : }
1521 : }
1522 :
1523 89 : if (destidx != inner)
1524 : {
1525 : /* The size of the symbol table changed. */
1526 49 : shdr_info[cnt].shdr.sh_size = newdata->d_size
1527 49 : = destidx * elsize;
1528 49 : any_symtab_changes = true;
1529 : }
1530 : else
1531 : {
1532 : /* The symbol table didn't really change. */
1533 40 : free (shdr_info[cnt].newsymidx);
1534 40 : shdr_info[cnt].newsymidx = NULL;
1535 : }
1536 : }
1537 : }
1538 :
1539 : /* If we have to, compute the offset of the section. */
1540 1755 : if (shdr_info[cnt].shdr.sh_offset == 0)
1541 : shdr_info[cnt].shdr.sh_offset
1542 1484 : = ((lastoffset + shdr_info[cnt].shdr.sh_addralign - 1)
1543 742 : & ~((GElf_Off) (shdr_info[cnt].shdr.sh_addralign - 1)));
1544 :
1545 : /* Set the section header in the new file. */
1546 1755 : if (unlikely (gelf_update_shdr (scn, &shdr_info[cnt].shdr) == 0))
1547 : /* There cannot be any overflows. */
1548 0 : INTERNAL_ERROR (fname);
1549 :
1550 : /* Remember the last section written so far. */
1551 3510 : GElf_Off filesz = (shdr_info[cnt].shdr.sh_type != SHT_NOBITS
1552 1755 : ? shdr_info[cnt].shdr.sh_size : 0);
1553 1755 : if (lastoffset < shdr_info[cnt].shdr.sh_offset + filesz)
1554 1666 : lastoffset = shdr_info[cnt].shdr.sh_offset + filesz;
1555 : }
1556 :
1557 : /* Adjust symbol references if symbol tables changed. */
1558 75 : if (any_symtab_changes)
1559 : /* Find all relocation sections which use this symbol table. */
1560 1639 : for (cnt = 1; cnt <= shdridx; ++cnt)
1561 : {
1562 : /* Update section headers when the data size has changed.
1563 : We also update the SHT_NOBITS section in the debug
1564 : file so that the section headers match in sh_size. */
1565 12 : inline void update_section_size (const Elf_Data *newdata)
1566 : {
1567 : GElf_Shdr shdr_mem;
1568 12 : GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
1569 12 : shdr->sh_size = newdata->d_size;
1570 12 : (void) gelf_update_shdr (scn, shdr);
1571 12 : if (debugelf != NULL)
1572 : {
1573 : /* libelf will use d_size to set sh_size. */
1574 2 : Elf_Data *debugdata = elf_getdata (elf_getscn (debugelf,
1575 : cnt), NULL);
1576 2 : if (debugdata == NULL)
1577 0 : INTERNAL_ERROR (fname);
1578 2 : debugdata->d_size = newdata->d_size;
1579 : }
1580 12 : }
1581 :
1582 1592 : if (shdr_info[cnt].idx == 0 && debug_fname == NULL)
1583 : /* Ignore sections which are discarded. When we are saving a
1584 : relocation section in a separate debug file, we must fix up
1585 : the symbol table references. */
1586 204 : continue;
1587 :
1588 1388 : const Elf32_Word symtabidx = shdr_info[cnt].old_sh_link;
1589 1388 : elf_assert (symtabidx < shnum + 2);
1590 1388 : const Elf32_Word *const newsymidx = shdr_info[symtabidx].newsymidx;
1591 1388 : switch (shdr_info[cnt].shdr.sh_type)
1592 : {
1593 : inline bool no_symtab_updates (void)
1594 : {
1595 : /* If the symbol table hasn't changed, do not do anything. */
1596 320 : if (shdr_info[symtabidx].newsymidx == NULL)
1597 : return true;
1598 :
1599 : /* If the symbol table is not discarded, but additionally
1600 : duplicated in the separate debug file and this section
1601 : is discarded, don't adjust anything. */
1602 : return (shdr_info[cnt].idx == 0
1603 281 : && shdr_info[symtabidx].debug_data != NULL);
1604 : }
1605 :
1606 : case SHT_REL:
1607 : case SHT_RELA:
1608 266 : if (no_symtab_updates ())
1609 : break;
1610 :
1611 312 : Elf_Data *d = elf_getdata (shdr_info[cnt].idx == 0
1612 : ? elf_getscn (debugelf, cnt)
1613 156 : : elf_getscn (newelf,
1614 : shdr_info[cnt].idx),
1615 : NULL);
1616 156 : elf_assert (d != NULL && d->d_buf != NULL
1617 : && shdr_info[cnt].shdr.sh_entsize != 0);
1618 156 : size_t nrels = (shdr_info[cnt].shdr.sh_size
1619 : / shdr_info[cnt].shdr.sh_entsize);
1620 :
1621 156 : size_t symsize = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
1622 312 : const Elf32_Word symidxn = (shdr_info[symtabidx].data->d_size
1623 156 : / symsize);
1624 156 : if (shdr_info[cnt].shdr.sh_type == SHT_REL)
1625 2402 : for (size_t relidx = 0; relidx < nrels; ++relidx)
1626 : {
1627 : GElf_Rel rel_mem;
1628 2402 : if (gelf_getrel (d, relidx, &rel_mem) == NULL)
1629 0 : INTERNAL_ERROR (fname);
1630 :
1631 2402 : size_t symidx = GELF_R_SYM (rel_mem.r_info);
1632 2402 : elf_assert (symidx < symidxn);
1633 2402 : if (newsymidx[symidx] != symidx)
1634 : {
1635 : rel_mem.r_info
1636 2202 : = GELF_R_INFO (newsymidx[symidx],
1637 : GELF_R_TYPE (rel_mem.r_info));
1638 :
1639 2202 : if (gelf_update_rel (d, relidx, &rel_mem) == 0)
1640 0 : INTERNAL_ERROR (fname);
1641 : }
1642 : }
1643 : else
1644 10737 : for (size_t relidx = 0; relidx < nrels; ++relidx)
1645 : {
1646 : GElf_Rela rel_mem;
1647 10737 : if (gelf_getrela (d, relidx, &rel_mem) == NULL)
1648 0 : INTERNAL_ERROR (fname);
1649 :
1650 10737 : size_t symidx = GELF_R_SYM (rel_mem.r_info);
1651 10737 : elf_assert (symidx < symidxn);
1652 10737 : if (newsymidx[symidx] != symidx)
1653 : {
1654 : rel_mem.r_info
1655 3483 : = GELF_R_INFO (newsymidx[symidx],
1656 : GELF_R_TYPE (rel_mem.r_info));
1657 :
1658 3483 : if (gelf_update_rela (d, relidx, &rel_mem) == 0)
1659 0 : INTERNAL_ERROR (fname);
1660 : }
1661 : }
1662 : break;
1663 :
1664 : case SHT_HASH:
1665 6 : if (no_symtab_updates ())
1666 : break;
1667 :
1668 : /* We have to recompute the hash table. */
1669 :
1670 6 : elf_assert (shdr_info[cnt].idx > 0);
1671 :
1672 : /* The hash section in the new file. */
1673 6 : scn = elf_getscn (newelf, shdr_info[cnt].idx);
1674 :
1675 : /* The symbol table data. */
1676 6 : Elf_Data *symd = elf_getdata (elf_getscn (newelf,
1677 6 : shdr_info[symtabidx].idx),
1678 : NULL);
1679 6 : elf_assert (symd != NULL && symd->d_buf != NULL);
1680 :
1681 : /* The hash table data. */
1682 6 : Elf_Data *hashd = elf_getdata (scn, NULL);
1683 6 : elf_assert (hashd != NULL && hashd->d_buf != NULL);
1684 :
1685 6 : if (shdr_info[cnt].shdr.sh_entsize == sizeof (Elf32_Word))
1686 : {
1687 : /* Sane arches first. */
1688 6 : elf_assert (hashd->d_size >= 2 * sizeof (Elf32_Word));
1689 6 : Elf32_Word *bucket = (Elf32_Word *) hashd->d_buf;
1690 :
1691 6 : size_t strshndx = shdr_info[symtabidx].old_sh_link;
1692 6 : size_t elsize = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
1693 :
1694 6 : Elf32_Word nchain = bucket[1];
1695 6 : Elf32_Word nbucket = bucket[0];
1696 12 : uint64_t used_buf = ((2ULL + nchain + nbucket)
1697 6 : * sizeof (Elf32_Word));
1698 6 : elf_assert (used_buf <= hashd->d_size);
1699 :
1700 : /* Adjust the nchain value. The symbol table size
1701 : changed. We keep the same size for the bucket array. */
1702 6 : bucket[1] = symd->d_size / elsize;
1703 6 : bucket += 2;
1704 6 : Elf32_Word *chain = bucket + nbucket;
1705 :
1706 : /* New size of the section. */
1707 12 : size_t n_size = ((2 + symd->d_size / elsize + nbucket)
1708 6 : * sizeof (Elf32_Word));
1709 6 : elf_assert (n_size <= hashd->d_size);
1710 6 : hashd->d_size = n_size;
1711 6 : update_section_size (hashd);
1712 :
1713 : /* Clear the arrays. */
1714 12 : memset (bucket, '\0',
1715 6 : (symd->d_size / elsize + nbucket)
1716 : * sizeof (Elf32_Word));
1717 :
1718 84 : for (size_t inner = shdr_info[symtabidx].shdr.sh_info;
1719 72 : inner < symd->d_size / elsize; ++inner)
1720 : {
1721 : GElf_Sym sym_mem;
1722 72 : GElf_Sym *sym = gelf_getsym (symd, inner, &sym_mem);
1723 72 : elf_assert (sym != NULL);
1724 :
1725 72 : const char *name = elf_strptr (elf, strshndx,
1726 72 : sym->st_name);
1727 72 : elf_assert (name != NULL && nbucket != 0);
1728 72 : size_t hidx = elf_hash (name) % nbucket;
1729 :
1730 72 : if (bucket[hidx] == 0)
1731 60 : bucket[hidx] = inner;
1732 : else
1733 : {
1734 12 : hidx = bucket[hidx];
1735 :
1736 24 : while (chain[hidx] != 0 && chain[hidx] < nchain)
1737 0 : hidx = chain[hidx];
1738 :
1739 12 : chain[hidx] = inner;
1740 : }
1741 : }
1742 : }
1743 : else
1744 0 : {
1745 : /* Alpha and S390 64-bit use 64-bit SHT_HASH entries. */
1746 0 : elf_assert (shdr_info[cnt].shdr.sh_entsize
1747 : == sizeof (Elf64_Xword));
1748 :
1749 0 : Elf64_Xword *bucket = (Elf64_Xword *) hashd->d_buf;
1750 :
1751 0 : size_t strshndx = shdr_info[symtabidx].old_sh_link;
1752 0 : size_t elsize = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
1753 :
1754 0 : elf_assert (symd->d_size >= 2 * sizeof (Elf64_Xword));
1755 0 : Elf64_Xword nbucket = bucket[0];
1756 0 : Elf64_Xword nchain = bucket[1];
1757 0 : uint64_t maxwords = hashd->d_size / sizeof (Elf64_Xword);
1758 0 : elf_assert (maxwords >= 2
1759 : && maxwords - 2 >= nbucket
1760 : && maxwords - 2 - nbucket >= nchain);
1761 :
1762 : /* Adjust the nchain value. The symbol table size
1763 : changed. We keep the same size for the bucket array. */
1764 0 : bucket[1] = symd->d_size / elsize;
1765 0 : bucket += 2;
1766 0 : Elf64_Xword *chain = bucket + nbucket;
1767 :
1768 : /* New size of the section. */
1769 0 : size_t n_size = ((2 + symd->d_size / elsize + nbucket)
1770 0 : * sizeof (Elf64_Xword));
1771 0 : elf_assert (n_size <= hashd->d_size);
1772 0 : hashd->d_size = n_size;
1773 0 : update_section_size (hashd);
1774 :
1775 : /* Clear the arrays. */
1776 0 : memset (bucket, '\0',
1777 0 : (symd->d_size / elsize + nbucket)
1778 : * sizeof (Elf64_Xword));
1779 :
1780 0 : for (size_t inner = shdr_info[symtabidx].shdr.sh_info;
1781 0 : inner < symd->d_size / elsize; ++inner)
1782 : {
1783 : GElf_Sym sym_mem;
1784 0 : GElf_Sym *sym = gelf_getsym (symd, inner, &sym_mem);
1785 0 : elf_assert (sym != NULL);
1786 :
1787 0 : const char *name = elf_strptr (elf, strshndx,
1788 0 : sym->st_name);
1789 0 : elf_assert (name != NULL && nbucket != 0);
1790 0 : size_t hidx = elf_hash (name) % nbucket;
1791 :
1792 0 : if (bucket[hidx] == 0)
1793 0 : bucket[hidx] = inner;
1794 : else
1795 : {
1796 : hidx = bucket[hidx];
1797 :
1798 0 : while (chain[hidx] != 0 && chain[hidx] < nchain)
1799 : hidx = chain[hidx];
1800 :
1801 0 : chain[hidx] = inner;
1802 : }
1803 : }
1804 : }
1805 : break;
1806 :
1807 : case SHT_GNU_versym:
1808 : /* If the symbol table changed we have to adjust the entries. */
1809 6 : if (no_symtab_updates ())
1810 : break;
1811 :
1812 6 : elf_assert (shdr_info[cnt].idx > 0);
1813 :
1814 : /* The symbol version section in the new file. */
1815 6 : scn = elf_getscn (newelf, shdr_info[cnt].idx);
1816 :
1817 : /* The symbol table data. */
1818 6 : symd = elf_getdata (elf_getscn (newelf, shdr_info[symtabidx].idx),
1819 : NULL);
1820 6 : elf_assert (symd != NULL && symd->d_buf != NULL);
1821 6 : size_t symz = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
1822 6 : const Elf32_Word syms = (shdr_info[symtabidx].data->d_size / symz);
1823 :
1824 : /* The version symbol data. */
1825 6 : Elf_Data *verd = elf_getdata (scn, NULL);
1826 6 : elf_assert (verd != NULL && verd->d_buf != NULL);
1827 :
1828 : /* The symbol version array. */
1829 6 : GElf_Half *verstab = (GElf_Half *) verd->d_buf;
1830 :
1831 : /* Walk through the list and */
1832 6 : size_t elsize = gelf_fsize (elf, verd->d_type, 1, EV_CURRENT);
1833 6 : Elf32_Word vers = verd->d_size / elsize;
1834 258 : for (size_t inner = 1; inner < vers && inner < syms; ++inner)
1835 252 : if (newsymidx[inner] != 0 && newsymidx[inner] < vers)
1836 : /* Overwriting the same array works since the
1837 : reordering can only move entries to lower indices
1838 : in the array. */
1839 204 : verstab[newsymidx[inner]] = verstab[inner];
1840 :
1841 : /* New size of the section. */
1842 6 : verd->d_size = gelf_fsize (newelf, verd->d_type,
1843 6 : symd->d_size
1844 6 : / gelf_fsize (elf, symd->d_type, 1,
1845 : EV_CURRENT),
1846 : EV_CURRENT);
1847 6 : update_section_size (verd);
1848 6 : break;
1849 :
1850 : case SHT_GROUP:
1851 3 : if (no_symtab_updates ())
1852 : break;
1853 :
1854 : /* Yes, the symbol table changed.
1855 : Update the section header of the section group. */
1856 2 : scn = elf_getscn (newelf, shdr_info[cnt].idx);
1857 : GElf_Shdr shdr_mem;
1858 2 : GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
1859 2 : elf_assert (shdr != NULL);
1860 :
1861 2 : size_t symsz = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
1862 4 : const Elf32_Word symn = (shdr_info[symtabidx].data->d_size
1863 2 : / symsz);
1864 2 : elf_assert (shdr->sh_info < symn);
1865 2 : shdr->sh_info = newsymidx[shdr->sh_info];
1866 :
1867 2 : (void) gelf_update_shdr (scn, shdr);
1868 2 : break;
1869 : }
1870 : }
1871 :
1872 : /* Remove any relocations between debug sections in ET_REL
1873 : for the debug file when requested. These relocations are always
1874 : zero based between the unallocated sections. */
1875 75 : if (debug_fname != NULL && removing_sections
1876 41 : && reloc_debug && ehdr->e_type == ET_REL)
1877 : {
1878 9 : scn = NULL;
1879 9 : cnt = 0;
1880 327 : while ((scn = elf_nextscn (debugelf, scn)) != NULL)
1881 : {
1882 309 : cnt++;
1883 : /* We need the actual section and header from the debugelf
1884 : not just the cached original in shdr_info because we
1885 : might want to change the size. */
1886 : GElf_Shdr shdr_mem;
1887 309 : GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
1888 309 : if (shdr->sh_type == SHT_REL || shdr->sh_type == SHT_RELA)
1889 : {
1890 : /* Make sure that this relocation section points to a
1891 : section to relocate with contents, that isn't
1892 : allocated and that is a debug section. */
1893 44 : Elf_Scn *tscn = elf_getscn (debugelf, shdr->sh_info);
1894 : GElf_Shdr tshdr_mem;
1895 44 : GElf_Shdr *tshdr = gelf_getshdr (tscn, &tshdr_mem);
1896 44 : if (tshdr->sh_type == SHT_NOBITS
1897 44 : || tshdr->sh_size == 0
1898 44 : || (tshdr->sh_flags & SHF_ALLOC) != 0)
1899 0 : continue;
1900 :
1901 44 : const char *tname = elf_strptr (debugelf, shstrndx,
1902 44 : tshdr->sh_name);
1903 44 : if (! tname || ! ebl_debugscn_p (ebl, tname))
1904 0 : continue;
1905 :
1906 : /* OK, lets relocate all trivial cross debug section
1907 : relocations. */
1908 44 : Elf_Data *reldata = elf_getdata (scn, NULL);
1909 44 : if (reldata == NULL || reldata->d_buf == NULL)
1910 0 : INTERNAL_ERROR (fname);
1911 :
1912 : /* Make sure we adjust the uncompressed debug data
1913 : (and recompress if necessary at the end). */
1914 : GElf_Chdr tchdr;
1915 44 : int tcompress_type = 0;
1916 44 : if (gelf_getchdr (tscn, &tchdr) != NULL)
1917 : {
1918 5 : tcompress_type = tchdr.ch_type;
1919 5 : if (elf_compress (tscn, 0, 0) != 1)
1920 0 : INTERNAL_ERROR (fname);
1921 : }
1922 :
1923 44 : Elf_Data *tdata = elf_getdata (tscn, NULL);
1924 44 : if (tdata == NULL || tdata->d_buf == NULL
1925 44 : || tdata->d_type != ELF_T_BYTE)
1926 0 : INTERNAL_ERROR (fname);
1927 :
1928 : /* Pick up the symbol table and shndx table to
1929 : resolve relocation symbol indexes. */
1930 44 : Elf64_Word symt = shdr->sh_link;
1931 : Elf_Data *symdata, *xndxdata;
1932 44 : elf_assert (symt < shnum + 2);
1933 44 : elf_assert (shdr_info[symt].symtab_idx < shnum + 2);
1934 88 : symdata = (shdr_info[symt].debug_data
1935 44 : ?: shdr_info[symt].data);
1936 88 : xndxdata = (shdr_info[shdr_info[symt].symtab_idx].debug_data
1937 44 : ?: shdr_info[shdr_info[symt].symtab_idx].data);
1938 :
1939 : /* Apply one relocation. Returns true when trivial
1940 : relocation actually done. */
1941 31874 : bool relocate (GElf_Addr offset, const GElf_Sxword addend,
1942 : bool is_rela, int rtype, int symndx)
1943 : {
1944 : /* R_*_NONE relocs can always just be removed. */
1945 31874 : if (rtype == 0)
1946 : return true;
1947 :
1948 : /* We only do simple absolute relocations. */
1949 31874 : Elf_Type type = ebl_reloc_simple_type (ebl, rtype);
1950 31874 : if (type == ELF_T_NUM)
1951 : return false;
1952 :
1953 : /* These are the types we can relocate. */
1954 : #define TYPES DO_TYPE (BYTE, Byte); DO_TYPE (HALF, Half); \
1955 : DO_TYPE (WORD, Word); DO_TYPE (SWORD, Sword); \
1956 : DO_TYPE (XWORD, Xword); DO_TYPE (SXWORD, Sxword)
1957 :
1958 : /* And only for relocations against other debug sections. */
1959 : GElf_Sym sym_mem;
1960 : Elf32_Word xndx;
1961 31874 : GElf_Sym *sym = gelf_getsymshndx (symdata, xndxdata,
1962 : symndx, &sym_mem,
1963 : &xndx);
1964 63748 : Elf32_Word sec = (sym->st_shndx == SHN_XINDEX
1965 31874 : ? xndx : sym->st_shndx);
1966 31874 : if (sec >= shnum + 2)
1967 0 : INTERNAL_ERROR (fname);
1968 :
1969 31874 : if (ebl_debugscn_p (ebl, shdr_info[sec].name))
1970 : {
1971 : size_t size;
1972 :
1973 : #define DO_TYPE(NAME, Name) GElf_##Name Name;
1974 : union { TYPES; } tmpbuf;
1975 : #undef DO_TYPE
1976 :
1977 22023 : switch (type)
1978 : {
1979 : #define DO_TYPE(NAME, Name) \
1980 : case ELF_T_##NAME: \
1981 : size = sizeof (GElf_##Name); \
1982 : tmpbuf.Name = 0; \
1983 : break;
1984 0 : TYPES;
1985 : #undef DO_TYPE
1986 : default:
1987 : return false;
1988 : }
1989 :
1990 22023 : if (offset > tdata->d_size
1991 22023 : || tdata->d_size - offset < size)
1992 : {
1993 0 : cleanup_debug ();
1994 0 : error (EXIT_FAILURE, 0, gettext ("bad relocation"));
1995 : }
1996 :
1997 : /* When the symbol value is zero then for SHT_REL
1998 : sections this is all that needs to be checked.
1999 : The addend is contained in the original data at
2000 : the offset already. So if the (section) symbol
2001 : address is zero and the given addend is zero
2002 : just remove the relocation, it isn't needed
2003 : anymore. */
2004 22023 : if (addend == 0 && sym->st_value == 0)
2005 : return true;
2006 :
2007 18781 : Elf_Data tmpdata =
2008 : {
2009 : .d_type = type,
2010 : .d_buf = &tmpbuf,
2011 : .d_size = size,
2012 : .d_version = EV_CURRENT,
2013 : };
2014 37562 : Elf_Data rdata =
2015 : {
2016 : .d_type = type,
2017 18781 : .d_buf = tdata->d_buf + offset,
2018 : .d_size = size,
2019 : .d_version = EV_CURRENT,
2020 : };
2021 :
2022 18781 : GElf_Addr value = sym->st_value;
2023 18781 : if (is_rela)
2024 : {
2025 : /* For SHT_RELA sections we just take the
2026 : given addend and add it to the value. */
2027 18781 : value += addend;
2028 : }
2029 : else
2030 : {
2031 : /* For SHT_REL sections we have to peek at
2032 : what is already in the section at the given
2033 : offset to get the addend. */
2034 0 : Elf_Data *d = gelf_xlatetom (debugelf, &tmpdata,
2035 : &rdata,
2036 0 : ehdr->e_ident[EI_DATA]);
2037 0 : if (d == NULL)
2038 0 : INTERNAL_ERROR (fname);
2039 0 : assert (d == &tmpdata);
2040 : }
2041 :
2042 18781 : switch (type)
2043 : {
2044 : #define DO_TYPE(NAME, Name) \
2045 : case ELF_T_##NAME: \
2046 : tmpbuf.Name += (GElf_##Name) value; \
2047 : break;
2048 0 : TYPES;
2049 : #undef DO_TYPE
2050 0 : default:
2051 0 : abort ();
2052 : }
2053 :
2054 : /* Now finally put in the new value. */
2055 18781 : Elf_Data *s = gelf_xlatetof (debugelf, &rdata,
2056 : &tmpdata,
2057 18781 : ehdr->e_ident[EI_DATA]);
2058 18781 : if (s == NULL)
2059 0 : INTERNAL_ERROR (fname);
2060 18781 : assert (s == &rdata);
2061 :
2062 : return true;
2063 : }
2064 : return false;
2065 : }
2066 :
2067 44 : if (shdr->sh_entsize == 0)
2068 0 : INTERNAL_ERROR (fname);
2069 :
2070 44 : size_t nrels = shdr->sh_size / shdr->sh_entsize;
2071 44 : size_t next = 0;
2072 44 : if (shdr->sh_type == SHT_REL)
2073 3212 : for (size_t relidx = 0; relidx < nrels; ++relidx)
2074 : {
2075 : GElf_Rel rel_mem;
2076 3212 : GElf_Rel *r = gelf_getrel (reldata, relidx, &rel_mem);
2077 3212 : if (! relocate (r->r_offset, 0, false,
2078 : GELF_R_TYPE (r->r_info),
2079 3212 : GELF_R_SYM (r->r_info)))
2080 : {
2081 18 : if (relidx != next)
2082 16 : gelf_update_rel (reldata, next, r);
2083 18 : ++next;
2084 : }
2085 : }
2086 : else
2087 28662 : for (size_t relidx = 0; relidx < nrels; ++relidx)
2088 : {
2089 : GElf_Rela rela_mem;
2090 28662 : GElf_Rela *r = gelf_getrela (reldata, relidx, &rela_mem);
2091 28662 : if (! relocate (r->r_offset, r->r_addend, true,
2092 : GELF_R_TYPE (r->r_info),
2093 28662 : GELF_R_SYM (r->r_info)))
2094 : {
2095 9833 : if (relidx != next)
2096 5510 : gelf_update_rela (reldata, next, r);
2097 9833 : ++next;
2098 : }
2099 : }
2100 :
2101 44 : nrels = next;
2102 44 : shdr->sh_size = reldata->d_size = nrels * shdr->sh_entsize;
2103 44 : gelf_update_shdr (scn, shdr);
2104 :
2105 44 : if (tcompress_type != 0)
2106 5 : if (elf_compress (tscn, tcompress_type, ELF_CHF_FORCE) != 1)
2107 0 : INTERNAL_ERROR (fname);
2108 : }
2109 : }
2110 : }
2111 :
2112 : /* Now that we have done all adjustments to the data,
2113 : we can actually write out the debug file. */
2114 75 : if (debug_fname != NULL && removing_sections)
2115 : {
2116 : /* Finally write the file. */
2117 41 : if (unlikely (elf_update (debugelf, ELF_C_WRITE) == -1))
2118 : {
2119 0 : error (0, 0, gettext ("while writing '%s': %s"),
2120 : tmp_debug_fname, elf_errmsg (-1));
2121 0 : result = 1;
2122 0 : goto fail_close;
2123 : }
2124 :
2125 : /* Create the real output file. First rename, then change the
2126 : mode. */
2127 41 : if (rename (tmp_debug_fname, debug_fname) != 0
2128 41 : || fchmod (debug_fd, mode) != 0)
2129 : {
2130 0 : error (0, errno, gettext ("while creating '%s'"), debug_fname);
2131 0 : result = 1;
2132 0 : goto fail_close;
2133 : }
2134 :
2135 : /* The temporary file does not exist anymore. */
2136 41 : free (tmp_debug_fname);
2137 41 : tmp_debug_fname = NULL;
2138 :
2139 41 : if (!remove_shdrs)
2140 : {
2141 : uint32_t debug_crc;
2142 41 : Elf_Data debug_crc_data =
2143 : {
2144 : .d_type = ELF_T_WORD,
2145 : .d_buf = &debug_crc,
2146 : .d_size = sizeof (debug_crc),
2147 : .d_version = EV_CURRENT
2148 : };
2149 :
2150 : /* Compute the checksum which we will add to the executable. */
2151 41 : if (crc32_file (debug_fd, &debug_crc) != 0)
2152 : {
2153 0 : error (0, errno, gettext ("\
2154 : while computing checksum for debug information"));
2155 0 : unlink (debug_fname);
2156 0 : result = 1;
2157 0 : goto fail_close;
2158 : }
2159 :
2160 : /* Store it in the debuglink section data. */
2161 41 : if (unlikely (gelf_xlatetof (newelf, &debuglink_crc_data,
2162 : &debug_crc_data, ehdr->e_ident[EI_DATA])
2163 : != &debuglink_crc_data))
2164 0 : INTERNAL_ERROR (fname);
2165 : }
2166 : }
2167 :
2168 : /* Finally finish the ELF header. Fill in the fields not handled by
2169 : libelf from the old file. */
2170 75 : newehdr = gelf_getehdr (newelf, &newehdr_mem);
2171 75 : if (newehdr == NULL)
2172 0 : INTERNAL_ERROR (fname);
2173 :
2174 150 : memcpy (newehdr->e_ident, ehdr->e_ident, EI_NIDENT);
2175 75 : newehdr->e_type = ehdr->e_type;
2176 75 : newehdr->e_machine = ehdr->e_machine;
2177 75 : newehdr->e_version = ehdr->e_version;
2178 75 : newehdr->e_entry = ehdr->e_entry;
2179 75 : newehdr->e_flags = ehdr->e_flags;
2180 75 : newehdr->e_phoff = ehdr->e_phoff;
2181 :
2182 : /* We need to position the section header table. */
2183 75 : const size_t offsize = gelf_fsize (elf, ELF_T_OFF, 1, EV_CURRENT);
2184 150 : newehdr->e_shoff = ((shdr_info[shdridx].shdr.sh_offset
2185 75 : + shdr_info[shdridx].shdr.sh_size + offsize - 1)
2186 75 : & ~((GElf_Off) (offsize - 1)));
2187 75 : newehdr->e_shentsize = gelf_fsize (elf, ELF_T_SHDR, 1, EV_CURRENT);
2188 :
2189 : /* The new section header string table index. */
2190 75 : if (likely (idx < SHN_HIRESERVE) && likely (idx != SHN_XINDEX))
2191 75 : newehdr->e_shstrndx = idx;
2192 : else
2193 : {
2194 : /* The index does not fit in the ELF header field. */
2195 0 : shdr_info[0].scn = elf_getscn (elf, 0);
2196 :
2197 0 : if (gelf_getshdr (shdr_info[0].scn, &shdr_info[0].shdr) == NULL)
2198 0 : INTERNAL_ERROR (fname);
2199 :
2200 0 : shdr_info[0].shdr.sh_link = idx;
2201 0 : (void) gelf_update_shdr (shdr_info[0].scn, &shdr_info[0].shdr);
2202 :
2203 0 : newehdr->e_shstrndx = SHN_XINDEX;
2204 : }
2205 :
2206 75 : if (gelf_update_ehdr (newelf, newehdr) == 0)
2207 : {
2208 0 : error (0, 0, gettext ("%s: error while creating ELF header: %s"),
2209 0 : output_fname ?: fname, elf_errmsg (-1));
2210 0 : cleanup_debug ();
2211 0 : return 1;
2212 : }
2213 :
2214 : /* We have everything from the old file. */
2215 75 : if (elf_cntl (elf, ELF_C_FDDONE) != 0)
2216 : {
2217 0 : error (0, 0, gettext ("%s: error while reading the file: %s"),
2218 : fname, elf_errmsg (-1));
2219 0 : cleanup_debug ();
2220 0 : return 1;
2221 : }
2222 :
2223 : /* The ELF library better follows our layout when this is not a
2224 : relocatable object file. */
2225 75 : elf_flagelf (newelf, ELF_C_SET,
2226 75 : (ehdr->e_type != ET_REL ? ELF_F_LAYOUT : 0)
2227 75 : | (permissive ? ELF_F_PERMISSIVE : 0));
2228 :
2229 : /* Finally write the file. */
2230 75 : if (elf_update (newelf, ELF_C_WRITE) == -1)
2231 : {
2232 0 : error (0, 0, gettext ("while writing '%s': %s"),
2233 0 : output_fname ?: fname, elf_errmsg (-1));
2234 0 : result = 1;
2235 : }
2236 :
2237 75 : if (remove_shdrs)
2238 : {
2239 : /* libelf can't cope without the section headers being properly intact.
2240 : So we just let it write them normally, and then we nuke them later. */
2241 :
2242 0 : if (newehdr->e_ident[EI_CLASS] == ELFCLASS32)
2243 : {
2244 : assert (offsetof (Elf32_Ehdr, e_shentsize) + sizeof (Elf32_Half)
2245 : == offsetof (Elf32_Ehdr, e_shnum));
2246 : assert (offsetof (Elf32_Ehdr, e_shnum) + sizeof (Elf32_Half)
2247 : == offsetof (Elf32_Ehdr, e_shstrndx));
2248 0 : const Elf32_Off zero_off = 0;
2249 0 : const Elf32_Half zero[3] = { 0, 0, SHN_UNDEF };
2250 0 : if (pwrite_retry (fd, &zero_off, sizeof zero_off,
2251 : offsetof (Elf32_Ehdr, e_shoff)) != sizeof zero_off
2252 0 : || (pwrite_retry (fd, zero, sizeof zero,
2253 : offsetof (Elf32_Ehdr, e_shentsize))
2254 : != sizeof zero)
2255 0 : || ftruncate (fd, shdr_info[shdridx].shdr.sh_offset) < 0)
2256 : {
2257 0 : error (0, errno, gettext ("while writing '%s'"),
2258 0 : output_fname ?: fname);
2259 0 : result = 1;
2260 : }
2261 : }
2262 : else
2263 : {
2264 : assert (offsetof (Elf64_Ehdr, e_shentsize) + sizeof (Elf64_Half)
2265 : == offsetof (Elf64_Ehdr, e_shnum));
2266 : assert (offsetof (Elf64_Ehdr, e_shnum) + sizeof (Elf64_Half)
2267 : == offsetof (Elf64_Ehdr, e_shstrndx));
2268 0 : const Elf64_Off zero_off = 0;
2269 0 : const Elf64_Half zero[3] = { 0, 0, SHN_UNDEF };
2270 0 : if (pwrite_retry (fd, &zero_off, sizeof zero_off,
2271 : offsetof (Elf64_Ehdr, e_shoff)) != sizeof zero_off
2272 0 : || (pwrite_retry (fd, zero, sizeof zero,
2273 : offsetof (Elf64_Ehdr, e_shentsize))
2274 : != sizeof zero)
2275 0 : || ftruncate (fd, shdr_info[shdridx].shdr.sh_offset) < 0)
2276 : {
2277 0 : error (0, errno, gettext ("while writing '%s'"),
2278 0 : output_fname ?: fname);
2279 0 : result = 1;
2280 : }
2281 : }
2282 : }
2283 :
2284 154 : fail_close:
2285 77 : if (shdr_info != NULL)
2286 : {
2287 : /* For some sections we might have created an table to map symbol
2288 : table indices. Or we might kept (original) data around to put
2289 : into the .debug file. */
2290 2606 : for (cnt = 1; cnt <= shdridx; ++cnt)
2291 : {
2292 2529 : free (shdr_info[cnt].newsymidx);
2293 2529 : if (shdr_info[cnt].debug_data != NULL)
2294 51 : free (shdr_info[cnt].debug_data->d_buf);
2295 : }
2296 :
2297 : /* Free data we allocated for the .gnu_debuglink section. */
2298 77 : free (debuglink_buf);
2299 :
2300 : /* Free the memory. */
2301 77 : if ((shnum + 2) * sizeof (struct shdr_info) > MAX_STACK_ALLOC)
2302 0 : free (shdr_info);
2303 : }
2304 :
2305 : /* Free other resources. */
2306 77 : if (shstrtab_data != NULL)
2307 75 : free (shstrtab_data->d_buf);
2308 77 : if (shst != NULL)
2309 77 : dwelf_strtab_free (shst);
2310 :
2311 : /* That was it. Close the descriptors. */
2312 77 : if (elf_end (newelf) != 0)
2313 : {
2314 0 : error (0, 0, gettext ("error while finishing '%s': %s"),
2315 0 : output_fname ?: fname, elf_errmsg (-1));
2316 0 : result = 1;
2317 : }
2318 :
2319 122 : if (debugelf != NULL && elf_end (debugelf) != 0)
2320 : {
2321 0 : error (0, 0, gettext ("error while finishing '%s': %s"), debug_fname,
2322 : elf_errmsg (-1));
2323 0 : result = 1;
2324 : }
2325 :
2326 154 : fail:
2327 : /* Close the EBL backend. */
2328 77 : if (ebl != NULL)
2329 34 : ebl_closebackend (ebl);
2330 :
2331 77 : cleanup_debug ();
2332 :
2333 : /* If requested, preserve the timestamp. */
2334 77 : if (tvp != NULL)
2335 : {
2336 0 : if (futimens (fd, tvp) != 0)
2337 : {
2338 0 : error (0, errno, gettext ("\
2339 : cannot set access and modification date of '%s'"),
2340 0 : output_fname ?: fname);
2341 0 : result = 1;
2342 : }
2343 : }
2344 :
2345 : /* Close the file descriptor if we created a new file. */
2346 77 : if (output_fname != NULL)
2347 : {
2348 63 : close (fd);
2349 63 : if (result != 0)
2350 0 : unlink (output_fname);
2351 : }
2352 :
2353 : return result;
2354 : }
2355 :
2356 : static void
2357 77 : cleanup_debug (void)
2358 : {
2359 77 : if (debug_fd >= 0)
2360 : {
2361 45 : if (tmp_debug_fname != NULL)
2362 : {
2363 4 : unlink (tmp_debug_fname);
2364 4 : free (tmp_debug_fname);
2365 4 : tmp_debug_fname = NULL;
2366 : }
2367 45 : close (debug_fd);
2368 45 : debug_fd = -1;
2369 : }
2370 77 : }
2371 :
2372 : static int
2373 : handle_ar (int fd, Elf *elf, const char *prefix, const char *fname,
2374 : struct timespec tvp[2])
2375 : {
2376 : size_t prefix_len = prefix == NULL ? 0 : strlen (prefix);
2377 : size_t fname_len = strlen (fname) + 1;
2378 : char new_prefix[prefix_len + 1 + fname_len];
2379 : char *cp = new_prefix;
2380 :
2381 : /* Create the full name of the file. */
2382 : if (prefix != NULL)
2383 : {
2384 : cp = mempcpy (cp, prefix, prefix_len);
2385 : *cp++ = ':';
2386 : }
2387 : memcpy (cp, fname, fname_len);
2388 :
2389 :
2390 : /* Process all the files contained in the archive. */
2391 : Elf *subelf;
2392 : Elf_Cmd cmd = ELF_C_RDWR;
2393 : int result = 0;
2394 : while ((subelf = elf_begin (fd, cmd, elf)) != NULL)
2395 : {
2396 : /* The the header for this element. */
2397 : Elf_Arhdr *arhdr = elf_getarhdr (subelf);
2398 :
2399 : if (elf_kind (subelf) == ELF_K_ELF)
2400 : result |= handle_elf (fd, subelf, new_prefix, arhdr->ar_name, 0, NULL);
2401 : else if (elf_kind (subelf) == ELF_K_AR)
2402 : result |= handle_ar (fd, subelf, new_prefix, arhdr->ar_name, NULL);
2403 :
2404 : /* Get next archive element. */
2405 : cmd = elf_next (subelf);
2406 : if (unlikely (elf_end (subelf) != 0))
2407 : INTERNAL_ERROR (fname);
2408 : }
2409 :
2410 : if (tvp != NULL)
2411 : {
2412 : if (unlikely (futimens (fd, tvp) != 0))
2413 : {
2414 : error (0, errno, gettext ("\
2415 : cannot set access and modification date of '%s'"), fname);
2416 : result = 1;
2417 : }
2418 : }
2419 :
2420 : if (unlikely (close (fd) != 0))
2421 : error (EXIT_FAILURE, errno, gettext ("while closing '%s'"), fname);
2422 :
2423 : return result;
2424 : }
2425 :
2426 :
2427 : #include "debugpred.h"
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