Line data Source code
1 : /* Discard section not used at runtime from object files.
2 : Copyright (C) 2000-2012, 2014, 2015, 2016, 2017, 2018 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 <fcntl.h>
28 : #include <fnmatch.h>
29 : #include <gelf.h>
30 : #include <libelf.h>
31 : #include <libintl.h>
32 : #include <locale.h>
33 : #include <stdbool.h>
34 : #include <stdio.h>
35 : #include <stdio_ext.h>
36 : #include <stdlib.h>
37 : #include <string.h>
38 : #include <unistd.h>
39 : #include <sys/stat.h>
40 : #include <sys/time.h>
41 :
42 : #include <elf-knowledge.h>
43 : #include <libebl.h>
44 : #include "libdwelf.h"
45 : #include <libeu.h>
46 : #include <system.h>
47 : #include <printversion.h>
48 :
49 : typedef uint8_t GElf_Byte;
50 :
51 : /* Name and version of program. */
52 : ARGP_PROGRAM_VERSION_HOOK_DEF = print_version;
53 :
54 : /* Bug report address. */
55 : ARGP_PROGRAM_BUG_ADDRESS_DEF = PACKAGE_BUGREPORT;
56 :
57 :
58 : /* Values for the parameters which have no short form. */
59 : #define OPT_REMOVE_COMMENT 0x100
60 : #define OPT_PERMISSIVE 0x101
61 : #define OPT_STRIP_SECTIONS 0x102
62 : #define OPT_RELOC_DEBUG 0x103
63 : #define OPT_KEEP_SECTION 0x104
64 : #define OPT_RELOC_DEBUG_ONLY 0x105
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 : { "reloc-debug-sections-only", OPT_RELOC_DEBUG_ONLY, NULL, 0,
87 : N_("Similar to --reloc-debug-sections, but resolve all trivial relocations between debug sections in place. No other stripping is performed (operation is not reversable, incompatible with -f, -g, --remove-comment and --remove-section)"), 0 },
88 : { "remove-comment", OPT_REMOVE_COMMENT, NULL, 0,
89 : N_("Remove .comment section"), 0 },
90 : { "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 },
91 : { "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 },
92 : { "permissive", OPT_PERMISSIVE, NULL, 0,
93 : N_("Relax a few rules to handle slightly broken ELF files"), 0 },
94 : { NULL, 0, NULL, 0, NULL, 0 }
95 : };
96 :
97 : /* Short description of program. */
98 : static const char doc[] = N_("Discard symbols from object files.");
99 :
100 : /* Strings for arguments in help texts. */
101 : static const char args_doc[] = N_("[FILE...]");
102 :
103 : /* Prototype for option handler. */
104 : static error_t parse_opt (int key, char *arg, struct argp_state *state);
105 :
106 : /* Data structure to communicate with argp functions. */
107 : static struct argp argp =
108 : {
109 : options, parse_opt, args_doc, doc, NULL, NULL, NULL
110 : };
111 :
112 :
113 : /* Print symbols in file named FNAME. */
114 : static int process_file (const char *fname);
115 :
116 : /* Handle one ELF file. */
117 : static int handle_elf (int fd, Elf *elf, const char *prefix,
118 : const char *fname, mode_t mode, struct timespec tvp[2]);
119 :
120 : /* Handle all files contained in the archive. */
121 : static int handle_ar (int fd, Elf *elf, const char *prefix, const char *fname,
122 : struct timespec tvp[2]) __attribute__ ((unused));
123 :
124 : static int debug_fd = -1;
125 : static char *tmp_debug_fname = NULL;
126 :
127 : /* Close debug file descriptor, if opened. And remove temporary debug file. */
128 : static void cleanup_debug (void);
129 :
130 : #define INTERNAL_ERROR(fname) \
131 : do { \
132 : cleanup_debug (); \
133 : error (EXIT_FAILURE, 0, gettext ("%s: INTERNAL ERROR %d (%s): %s"), \
134 : fname, __LINE__, PACKAGE_VERSION, elf_errmsg (-1)); \
135 : } while (0)
136 :
137 :
138 : /* Name of the output file. */
139 : static const char *output_fname;
140 :
141 : /* Name of the debug output file. */
142 : static const char *debug_fname;
143 :
144 : /* Name to pretend the debug output file has. */
145 : static const char *debug_fname_embed;
146 :
147 : /* If true output files shall have same date as the input file. */
148 : static bool preserve_dates;
149 :
150 : /* If true .comment sections will be removed. */
151 : static bool remove_comment;
152 :
153 : /* If true remove all debug sections. */
154 : static bool remove_debug;
155 :
156 : /* If true remove all section headers. */
157 : static bool remove_shdrs;
158 :
159 : /* If true relax some ELF rules for input files. */
160 : static bool permissive;
161 :
162 : /* If true perform relocations between debug sections. */
163 : static bool reloc_debug;
164 :
165 : /* If true perform relocations between debug sections only. */
166 : static bool reloc_debug_only;
167 :
168 : /* Sections the user explicitly wants to keep or remove. */
169 : struct section_pattern
170 : {
171 : char *pattern;
172 : struct section_pattern *next;
173 : };
174 :
175 : static struct section_pattern *keep_secs = NULL;
176 : static struct section_pattern *remove_secs = NULL;
177 :
178 : static void
179 10 : add_pattern (struct section_pattern **patterns, const char *pattern)
180 : {
181 10 : struct section_pattern *p = xmalloc (sizeof *p);
182 10 : p->pattern = xstrdup (pattern);
183 10 : p->next = *patterns;
184 10 : *patterns = p;
185 10 : }
186 :
187 : static void
188 226 : free_sec_patterns (struct section_pattern *patterns)
189 : {
190 226 : struct section_pattern *pattern = patterns;
191 236 : while (pattern != NULL)
192 : {
193 10 : struct section_pattern *p = pattern;
194 10 : pattern = p->next;
195 10 : free (p->pattern);
196 10 : free (p);
197 : }
198 226 : }
199 :
200 : static void
201 113 : free_patterns (void)
202 : {
203 113 : free_sec_patterns (keep_secs);
204 113 : free_sec_patterns (remove_secs);
205 113 : }
206 :
207 : static bool
208 : section_name_matches (struct section_pattern *patterns, const char *name)
209 : {
210 399313 : struct section_pattern *pattern = patterns;
211 399564 : while (pattern != NULL)
212 : {
213 269 : if (fnmatch (pattern->pattern, name, FNM_EXTMATCH) == 0)
214 : return true;
215 251 : pattern = pattern->next;
216 : }
217 : return false;
218 : }
219 :
220 :
221 : int
222 113 : main (int argc, char *argv[])
223 : {
224 113 : int remaining;
225 113 : int result = 0;
226 :
227 : /* We use no threads here which can interfere with handling a stream. */
228 113 : __fsetlocking (stdin, FSETLOCKING_BYCALLER);
229 113 : __fsetlocking (stdout, FSETLOCKING_BYCALLER);
230 113 : __fsetlocking (stderr, FSETLOCKING_BYCALLER);
231 :
232 : /* Set locale. */
233 113 : setlocale (LC_ALL, "");
234 :
235 : /* Make sure the message catalog can be found. */
236 113 : bindtextdomain (PACKAGE_TARNAME, LOCALEDIR);
237 :
238 : /* Initialize the message catalog. */
239 113 : textdomain (PACKAGE_TARNAME);
240 :
241 : /* Parse and process arguments. */
242 113 : if (argp_parse (&argp, argc, argv, 0, &remaining, NULL) != 0)
243 : return EXIT_FAILURE;
244 :
245 113 : if (reloc_debug && debug_fname == NULL)
246 0 : error (EXIT_FAILURE, 0,
247 0 : gettext ("--reloc-debug-sections used without -f"));
248 :
249 113 : if (reloc_debug_only &&
250 15 : (debug_fname != NULL || remove_secs != NULL
251 15 : || remove_comment == true || remove_debug == true))
252 0 : error (EXIT_FAILURE, 0,
253 0 : gettext ("--reloc-debug-sections-only incompatible with -f, -g, --remove-comment and --remove-section"));
254 :
255 : /* Tell the library which version we are expecting. */
256 113 : elf_version (EV_CURRENT);
257 :
258 113 : if (remaining == argc)
259 : /* The user didn't specify a name so we use a.out. */
260 5 : result = process_file ("a.out");
261 : else
262 : {
263 : /* If we have seen the '-o' or '-f' option there must be exactly one
264 : input file. */
265 108 : if ((output_fname != NULL || debug_fname != NULL)
266 79 : && remaining + 1 < argc)
267 0 : error (EXIT_FAILURE, 0, gettext ("\
268 : Only one input file allowed together with '-o' and '-f'"));
269 :
270 : /* Process all the remaining files. */
271 108 : do
272 108 : result |= process_file (argv[remaining]);
273 108 : while (++remaining < argc);
274 : }
275 :
276 113 : free_patterns ();
277 113 : return result;
278 : }
279 :
280 :
281 : /* Handle program arguments. */
282 : static error_t
283 781 : parse_opt (int key, char *arg, struct argp_state *state)
284 : {
285 781 : switch (key)
286 : {
287 62 : case 'f':
288 62 : if (debug_fname != NULL)
289 : {
290 0 : error (0, 0, gettext ("-f option specified twice"));
291 0 : return EINVAL;
292 : }
293 62 : debug_fname = arg;
294 62 : break;
295 :
296 6 : case 'F':
297 6 : if (debug_fname_embed != NULL)
298 : {
299 0 : error (0, 0, gettext ("-F option specified twice"));
300 0 : return EINVAL;
301 : }
302 6 : debug_fname_embed = arg;
303 6 : break;
304 :
305 81 : case 'o':
306 81 : if (output_fname != NULL)
307 : {
308 0 : error (0, 0, gettext ("-o option specified twice"));
309 0 : return EINVAL;
310 : }
311 81 : output_fname = arg;
312 81 : break;
313 :
314 0 : case 'p':
315 0 : preserve_dates = true;
316 0 : break;
317 :
318 15 : case OPT_RELOC_DEBUG:
319 15 : reloc_debug = true;
320 15 : break;
321 :
322 15 : case OPT_RELOC_DEBUG_ONLY:
323 15 : reloc_debug_only = true;
324 15 : break;
325 :
326 1 : case OPT_REMOVE_COMMENT:
327 1 : remove_comment = true;
328 1 : break;
329 :
330 4 : case 'R':
331 4 : if (fnmatch (arg, ".comment", FNM_EXTMATCH) == 0)
332 0 : remove_comment = true;
333 4 : add_pattern (&remove_secs, arg);
334 4 : break;
335 :
336 6 : case OPT_KEEP_SECTION:
337 6 : add_pattern (&keep_secs, arg);
338 6 : break;
339 :
340 26 : case 'g':
341 : case 'd':
342 : case 'S':
343 26 : remove_debug = true;
344 26 : break;
345 :
346 0 : case OPT_STRIP_SECTIONS:
347 0 : remove_shdrs = true;
348 0 : break;
349 :
350 0 : case OPT_PERMISSIVE:
351 0 : permissive = true;
352 0 : break;
353 :
354 : case 's': /* Ignored for compatibility. */
355 : break;
356 :
357 113 : case ARGP_KEY_SUCCESS:
358 113 : if (remove_comment == true
359 2 : && section_name_matches (keep_secs, ".comment"))
360 : {
361 0 : argp_error (state,
362 0 : gettext ("cannot both keep and remove .comment section"));
363 0 : return EINVAL;
364 : }
365 : break;
366 :
367 : default:
368 : return ARGP_ERR_UNKNOWN;
369 : }
370 : return 0;
371 : }
372 :
373 : static const char *
374 88424 : secndx_name (Elf *elf, size_t ndx)
375 : {
376 88424 : size_t shstrndx;
377 88424 : GElf_Shdr mem;
378 88424 : Elf_Scn *sec = elf_getscn (elf, ndx);
379 88424 : GElf_Shdr *shdr = gelf_getshdr (sec, &mem);
380 88424 : if (shdr == NULL || elf_getshdrstrndx (elf, &shstrndx) < 0)
381 0 : return "???";
382 88424 : return elf_strptr (elf, shstrndx, shdr->sh_name) ?: "???";
383 : }
384 :
385 : /* Get the extended section index table data for a symbol table section. */
386 : static Elf_Data *
387 132 : get_xndxdata (Elf *elf, Elf_Scn *symscn)
388 : {
389 132 : Elf_Data *xndxdata = NULL;
390 132 : GElf_Shdr shdr_mem;
391 132 : GElf_Shdr *shdr = gelf_getshdr (symscn, &shdr_mem);
392 132 : if (shdr != NULL && shdr->sh_type == SHT_SYMTAB)
393 : {
394 132 : size_t scnndx = elf_ndxscn (symscn);
395 132 : Elf_Scn *xndxscn = NULL;
396 4292 : while ((xndxscn = elf_nextscn (elf, xndxscn)) != NULL)
397 : {
398 4160 : GElf_Shdr xndxshdr_mem;
399 4160 : GElf_Shdr *xndxshdr = gelf_getshdr (xndxscn, &xndxshdr_mem);
400 :
401 4160 : if (xndxshdr != NULL
402 4160 : && xndxshdr->sh_type == SHT_SYMTAB_SHNDX
403 0 : && xndxshdr->sh_link == scnndx)
404 : {
405 0 : xndxdata = elf_getdata (xndxscn, NULL);
406 0 : break;
407 : }
408 : }
409 : }
410 :
411 132 : return xndxdata;
412 : }
413 :
414 : /* Updates the shdrstrndx for the given Elf by updating the Ehdr and
415 : possibly the section zero extension field. Returns zero on success. */
416 : static int
417 188 : update_shdrstrndx (Elf *elf, size_t shdrstrndx)
418 : {
419 188 : GElf_Ehdr ehdr;
420 188 : if (gelf_getehdr (elf, &ehdr) == 0)
421 : return 1;
422 :
423 188 : if (shdrstrndx < SHN_LORESERVE)
424 185 : ehdr.e_shstrndx = shdrstrndx;
425 : else
426 : {
427 3 : ehdr.e_shstrndx = SHN_XINDEX;
428 3 : Elf_Scn *scn0 = elf_getscn (elf, 0);
429 3 : GElf_Shdr shdr0_mem;
430 3 : GElf_Shdr *shdr0 = gelf_getshdr (scn0, &shdr0_mem);
431 3 : if (shdr0 == NULL)
432 0 : return 1;
433 :
434 3 : shdr0->sh_link = shdrstrndx;
435 3 : if (gelf_update_shdr (scn0, shdr0) == 0)
436 : return 1;
437 : }
438 :
439 188 : if (unlikely (gelf_update_ehdr (elf, &ehdr) == 0))
440 0 : return 1;
441 :
442 : return 0;
443 : }
444 :
445 : /* Remove any relocations between debug sections in ET_REL
446 : for the debug file when requested. These relocations are always
447 : zero based between the unallocated sections. */
448 : static void
449 29 : remove_debug_relocations (Ebl *ebl, Elf *elf, GElf_Ehdr *ehdr,
450 : const char *fname, size_t shstrndx)
451 : {
452 29 : Elf_Scn *scn = NULL;
453 926 : while ((scn = elf_nextscn (elf, scn)) != NULL)
454 : {
455 : /* We need the actual section and header from the elf
456 : not just the cached original in shdr_info because we
457 : might want to change the size. */
458 897 : GElf_Shdr shdr_mem;
459 897 : GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
460 897 : if (shdr->sh_type == SHT_REL || shdr->sh_type == SHT_RELA)
461 : {
462 : /* Make sure that this relocation section points to a
463 : section to relocate with contents, that isn't
464 : allocated and that is a debug section. */
465 132 : Elf_Scn *tscn = elf_getscn (elf, shdr->sh_info);
466 132 : GElf_Shdr tshdr_mem;
467 132 : GElf_Shdr *tshdr = gelf_getshdr (tscn, &tshdr_mem);
468 132 : if (tshdr->sh_type == SHT_NOBITS
469 132 : || tshdr->sh_size == 0
470 132 : || (tshdr->sh_flags & SHF_ALLOC) != 0)
471 0 : continue;
472 :
473 396 : const char *tname = elf_strptr (elf, shstrndx,
474 132 : tshdr->sh_name);
475 132 : if (! tname || ! ebl_debugscn_p (ebl, tname))
476 0 : continue;
477 :
478 : /* OK, lets relocate all trivial cross debug section
479 : relocations. */
480 132 : Elf_Data *reldata = elf_getdata (scn, NULL);
481 132 : if (reldata == NULL || reldata->d_buf == NULL)
482 0 : INTERNAL_ERROR (fname);
483 :
484 : /* Make sure we adjust the uncompressed debug data
485 : (and recompress if necessary at the end). */
486 132 : GElf_Chdr tchdr;
487 132 : int tcompress_type = 0;
488 132 : bool is_gnu_compressed = false;
489 132 : if (strncmp (tname, ".zdebug", strlen ("zdebug")) == 0)
490 : {
491 4 : is_gnu_compressed = true;
492 4 : if (elf_compress_gnu (tscn, 0, 0) != 1)
493 0 : INTERNAL_ERROR (fname);
494 : }
495 : else
496 : {
497 128 : if (gelf_getchdr (tscn, &tchdr) != NULL)
498 : {
499 14 : tcompress_type = tchdr.ch_type;
500 14 : if (elf_compress (tscn, 0, 0) != 1)
501 0 : INTERNAL_ERROR (fname);
502 : }
503 : }
504 :
505 132 : Elf_Data *tdata = elf_getdata (tscn, NULL);
506 132 : if (tdata == NULL || tdata->d_buf == NULL
507 132 : || tdata->d_type != ELF_T_BYTE)
508 0 : INTERNAL_ERROR (fname);
509 :
510 : /* Pick up the symbol table and shndx table to
511 : resolve relocation symbol indexes. */
512 132 : Elf64_Word symt = shdr->sh_link;
513 132 : Elf_Data *symdata, *xndxdata;
514 132 : Elf_Scn * symscn = elf_getscn (elf, symt);
515 132 : symdata = elf_getdata (symscn, NULL);
516 132 : xndxdata = get_xndxdata (elf, symscn);
517 132 : if (symdata == NULL)
518 0 : INTERNAL_ERROR (fname);
519 :
520 : /* Apply one relocation. Returns true when trivial
521 : relocation actually done. */
522 88564 : bool relocate (GElf_Addr offset, const GElf_Sxword addend,
523 : bool is_rela, int rtype, int symndx)
524 : {
525 : /* R_*_NONE relocs can always just be removed. */
526 88432 : if (rtype == 0)
527 : return true;
528 :
529 : /* We only do simple absolute relocations. */
530 88432 : int addsub = 0;
531 88432 : Elf_Type type = ebl_reloc_simple_type (ebl, rtype, &addsub);
532 88432 : if (type == ELF_T_NUM)
533 : return false;
534 :
535 : /* These are the types we can relocate. */
536 : #define TYPES DO_TYPE (BYTE, Byte); DO_TYPE (HALF, Half); \
537 : DO_TYPE (WORD, Word); DO_TYPE (SWORD, Sword); \
538 : DO_TYPE (XWORD, Xword); DO_TYPE (SXWORD, Sxword)
539 :
540 : /* And only for relocations against other debug sections. */
541 88424 : GElf_Sym sym_mem;
542 88424 : Elf32_Word xndx;
543 88424 : GElf_Sym *sym = gelf_getsymshndx (symdata, xndxdata,
544 : symndx, &sym_mem,
545 : &xndx);
546 176848 : Elf32_Word sec = (sym->st_shndx == SHN_XINDEX
547 88424 : ? xndx : sym->st_shndx);
548 :
549 88424 : if (ebl_debugscn_p (ebl, secndx_name (elf, sec)))
550 : {
551 55948 : size_t size;
552 :
553 : #define DO_TYPE(NAME, Name) GElf_##Name Name;
554 55948 : union { TYPES; } tmpbuf;
555 : #undef DO_TYPE
556 :
557 55948 : switch (type)
558 : {
559 : #define DO_TYPE(NAME, Name) \
560 : case ELF_T_##NAME: \
561 : size = sizeof (GElf_##Name); \
562 : tmpbuf.Name = 0; \
563 : break;
564 55948 : TYPES;
565 : #undef DO_TYPE
566 : default:
567 : return false;
568 : }
569 :
570 55948 : if (offset > tdata->d_size
571 55948 : || tdata->d_size - offset < size)
572 : {
573 0 : cleanup_debug ();
574 0 : error (EXIT_FAILURE, 0, gettext ("bad relocation"));
575 : }
576 :
577 : /* When the symbol value is zero then for SHT_REL
578 : sections this is all that needs to be checked.
579 : The addend is contained in the original data at
580 : the offset already. So if the (section) symbol
581 : address is zero and the given addend is zero
582 : just remove the relocation, it isn't needed
583 : anymore. */
584 55948 : if (addend == 0 && sym->st_value == 0)
585 : return true;
586 :
587 49404 : Elf_Data tmpdata =
588 : {
589 : .d_type = type,
590 : .d_buf = &tmpbuf,
591 : .d_size = size,
592 : .d_version = EV_CURRENT,
593 : };
594 98808 : Elf_Data rdata =
595 : {
596 : .d_type = type,
597 49404 : .d_buf = tdata->d_buf + offset,
598 : .d_size = size,
599 : .d_version = EV_CURRENT,
600 : };
601 :
602 49404 : GElf_Addr value = sym->st_value;
603 49404 : if (is_rela)
604 : {
605 : /* For SHT_RELA sections we just take the
606 : given addend and add it to the value. */
607 49404 : value += addend;
608 : /* For ADD/SUB relocations we need to fetch the
609 : current section contents. */
610 49404 : if (addsub != 0)
611 : {
612 0 : Elf_Data *d = gelf_xlatetom (elf, &tmpdata,
613 : &rdata,
614 0 : ehdr->e_ident[EI_DATA]);
615 0 : if (d == NULL)
616 0 : INTERNAL_ERROR (fname);
617 0 : assert (d == &tmpdata);
618 : }
619 : }
620 : else
621 : {
622 : /* For SHT_REL sections we have to peek at
623 : what is already in the section at the given
624 : offset to get the addend. */
625 0 : Elf_Data *d = gelf_xlatetom (elf, &tmpdata,
626 : &rdata,
627 0 : ehdr->e_ident[EI_DATA]);
628 0 : if (d == NULL)
629 0 : INTERNAL_ERROR (fname);
630 0 : assert (d == &tmpdata);
631 : }
632 :
633 49404 : switch (type)
634 : {
635 : #define DO_TYPE(NAME, Name) \
636 : case ELF_T_##NAME: \
637 : if (addsub < 0) \
638 : tmpbuf.Name -= (GElf_##Name) value; \
639 : else \
640 : tmpbuf.Name += (GElf_##Name) value; \
641 : break;
642 49404 : TYPES;
643 : #undef DO_TYPE
644 0 : default:
645 0 : abort ();
646 : }
647 :
648 : /* Now finally put in the new value. */
649 148212 : Elf_Data *s = gelf_xlatetof (elf, &rdata,
650 : &tmpdata,
651 49404 : ehdr->e_ident[EI_DATA]);
652 49404 : if (s == NULL)
653 0 : INTERNAL_ERROR (fname);
654 49404 : assert (s == &rdata);
655 :
656 : return true;
657 : }
658 : return false;
659 : }
660 :
661 132 : if (shdr->sh_entsize == 0)
662 0 : INTERNAL_ERROR (fname);
663 :
664 132 : size_t nrels = shdr->sh_size / shdr->sh_entsize;
665 132 : size_t next = 0;
666 132 : if (shdr->sh_type == SHT_REL)
667 6432 : for (size_t relidx = 0; relidx < nrels; ++relidx)
668 : {
669 6424 : GElf_Rel rel_mem;
670 6424 : GElf_Rel *r = gelf_getrel (reldata, relidx, &rel_mem);
671 6424 : if (! relocate (r->r_offset, 0, false,
672 : GELF_R_TYPE (r->r_info),
673 6424 : GELF_R_SYM (r->r_info)))
674 : {
675 36 : if (relidx != next)
676 32 : gelf_update_rel (reldata, next, r);
677 36 : ++next;
678 : }
679 : }
680 : else
681 82132 : for (size_t relidx = 0; relidx < nrels; ++relidx)
682 : {
683 82008 : GElf_Rela rela_mem;
684 82008 : GElf_Rela *r = gelf_getrela (reldata, relidx, &rela_mem);
685 82008 : if (! relocate (r->r_offset, r->r_addend, true,
686 : GELF_R_TYPE (r->r_info),
687 82008 : GELF_R_SYM (r->r_info)))
688 : {
689 32448 : if (relidx != next)
690 15262 : gelf_update_rela (reldata, next, r);
691 32448 : ++next;
692 : }
693 : }
694 :
695 132 : nrels = next;
696 132 : shdr->sh_size = reldata->d_size = nrels * shdr->sh_entsize;
697 132 : gelf_update_shdr (scn, shdr);
698 :
699 132 : if (is_gnu_compressed)
700 : {
701 4 : if (elf_compress_gnu (tscn, 1, ELF_CHF_FORCE) != 1)
702 0 : INTERNAL_ERROR (fname);
703 : }
704 128 : else if (tcompress_type != 0)
705 : {
706 14 : if (elf_compress (tscn, tcompress_type, ELF_CHF_FORCE) != 1)
707 0 : INTERNAL_ERROR (fname);
708 : }
709 : }
710 : }
711 29 : }
712 :
713 : static int
714 113 : process_file (const char *fname)
715 : {
716 : /* If we have to preserve the modify and access timestamps get them
717 : now. We cannot use fstat() after opening the file since the open
718 : would change the access time. */
719 113 : struct stat pre_st;
720 113 : struct timespec tv[2];
721 113 : again:
722 113 : if (preserve_dates)
723 : {
724 0 : if (stat (fname, &pre_st) != 0)
725 : {
726 0 : error (0, errno, gettext ("cannot stat input file '%s'"), fname);
727 0 : return 1;
728 : }
729 :
730 : /* If we have to preserve the timestamp, we need it in the
731 : format utimes() understands. */
732 0 : tv[0] = pre_st.st_atim;
733 0 : tv[1] = pre_st.st_mtim;
734 : }
735 :
736 : /* Open the file. */
737 194 : int fd = open (fname, output_fname == NULL ? O_RDWR : O_RDONLY);
738 113 : if (fd == -1)
739 : {
740 0 : error (0, errno, gettext ("while opening '%s'"), fname);
741 0 : return 1;
742 : }
743 :
744 : /* We always use fstat() even if we called stat() before. This is
745 : done to make sure the information returned by stat() is for the
746 : same file. */
747 113 : struct stat st;
748 113 : if (fstat (fd, &st) != 0)
749 : {
750 0 : error (0, errno, gettext ("cannot stat input file '%s'"), fname);
751 0 : return 1;
752 : }
753 : /* Paranoid mode on. */
754 113 : if (preserve_dates
755 0 : && (st.st_ino != pre_st.st_ino || st.st_dev != pre_st.st_dev))
756 : {
757 : /* We detected a race. Try again. */
758 0 : close (fd);
759 0 : goto again;
760 : }
761 :
762 : /* Now get the ELF descriptor. */
763 194 : Elf *elf = elf_begin (fd, output_fname == NULL ? ELF_C_RDWR : ELF_C_READ,
764 : NULL);
765 113 : int result;
766 113 : switch (elf_kind (elf))
767 : {
768 113 : case ELF_K_ELF:
769 339 : result = handle_elf (fd, elf, NULL, fname, st.st_mode & ACCESSPERMS,
770 113 : preserve_dates ? tv : NULL);
771 113 : break;
772 :
773 0 : case ELF_K_AR:
774 : /* It is not possible to strip the content of an archive direct
775 : the output to a specific file. */
776 0 : if (unlikely (output_fname != NULL || debug_fname != NULL))
777 : {
778 0 : error (0, 0, gettext ("%s: cannot use -o or -f when stripping archive"),
779 : fname);
780 0 : result = 1;
781 : }
782 : else
783 : {
784 : /* We would like to support ar archives, but currently it just
785 : doesn't work at all since we call elf_clone on the members
786 : which doesn't really support ar members.
787 : result = handle_ar (fd, elf, NULL, fname,
788 : preserve_dates ? tv : NULL);
789 : */
790 0 : error (0, 0, gettext ("%s: no support for stripping archive"),
791 : fname);
792 0 : result = 1;
793 : }
794 : break;
795 :
796 0 : default:
797 0 : error (0, 0, gettext ("%s: File format not recognized"), fname);
798 0 : result = 1;
799 0 : break;
800 : }
801 :
802 113 : if (unlikely (elf_end (elf) != 0))
803 0 : INTERNAL_ERROR (fname);
804 :
805 113 : close (fd);
806 :
807 113 : return result;
808 : }
809 :
810 : /* Processing for --reloc-debug-sections-only. */
811 : static int
812 15 : handle_debug_relocs (Elf *elf, Ebl *ebl, Elf *new_elf,
813 : GElf_Ehdr *ehdr, const char *fname, size_t shstrndx,
814 : GElf_Off *last_offset, GElf_Xword *last_size)
815 : {
816 :
817 : /* Copy over the ELF header. */
818 15 : if (gelf_update_ehdr (new_elf, ehdr) == 0)
819 : {
820 0 : error (0, 0, "couldn't update new ehdr: %s", elf_errmsg (-1));
821 0 : return 1;
822 : }
823 :
824 : /* Copy over sections and record end of allocated sections. */
825 : GElf_Off lastoffset = 0;
826 : Elf_Scn *scn = NULL;
827 483 : while ((scn = elf_nextscn (elf, scn)) != NULL)
828 : {
829 : /* Get the header. */
830 468 : GElf_Shdr shdr;
831 468 : if (gelf_getshdr (scn, &shdr) == NULL)
832 : {
833 0 : error (0, 0, "couldn't get shdr: %s", elf_errmsg (-1));
834 0 : return 1;
835 : }
836 :
837 : /* Create new section. */
838 468 : Elf_Scn *new_scn = elf_newscn (new_elf);
839 468 : if (new_scn == NULL)
840 : {
841 0 : error (0, 0, "couldn't create new section: %s", elf_errmsg (-1));
842 0 : return 1;
843 : }
844 :
845 468 : if (gelf_update_shdr (new_scn, &shdr) == 0)
846 : {
847 0 : error (0, 0, "couldn't update shdr: %s", elf_errmsg (-1));
848 0 : return 1;
849 : }
850 :
851 : /* Copy over section data. */
852 : Elf_Data *data = NULL;
853 936 : while ((data = elf_getdata (scn, data)) != NULL)
854 : {
855 468 : Elf_Data *new_data = elf_newdata (new_scn);
856 468 : if (new_data == NULL)
857 : {
858 0 : error (0, 0, "couldn't create new section data: %s",
859 : elf_errmsg (-1));
860 0 : return 1;
861 : }
862 468 : *new_data = *data;
863 : }
864 :
865 : /* Record last offset of allocated section. */
866 468 : if ((shdr.sh_flags & SHF_ALLOC) != 0)
867 : {
868 324 : GElf_Off filesz = (shdr.sh_type != SHT_NOBITS
869 162 : ? shdr.sh_size : 0);
870 162 : if (lastoffset < shdr.sh_offset + filesz)
871 33 : lastoffset = shdr.sh_offset + filesz;
872 : }
873 : }
874 :
875 : /* Make sure section header name table is setup correctly, we'll
876 : need it to determine whether to relocate sections. */
877 15 : if (update_shdrstrndx (new_elf, shstrndx) != 0)
878 : {
879 0 : error (0, 0, "error updating shdrstrndx: %s", elf_errmsg (-1));
880 0 : return 1;
881 : }
882 :
883 : /* Adjust the relocation sections. */
884 15 : remove_debug_relocations (ebl, new_elf, ehdr, fname, shstrndx);
885 :
886 : /* Adjust the offsets of the non-allocated sections, so they come after
887 : the allocated sections. */
888 15 : scn = NULL;
889 483 : while ((scn = elf_nextscn (new_elf, scn)) != NULL)
890 : {
891 : /* Get the header. */
892 468 : GElf_Shdr shdr;
893 468 : if (gelf_getshdr (scn, &shdr) == NULL)
894 : {
895 0 : error (0, 0, "couldn't get shdr: %s", elf_errmsg (-1));
896 0 : return 1;
897 : }
898 :
899 : /* Adjust non-allocated section offsets to be after any allocated. */
900 468 : if ((shdr.sh_flags & SHF_ALLOC) == 0)
901 : {
902 612 : shdr.sh_offset = ((lastoffset + shdr.sh_addralign - 1)
903 306 : & ~((GElf_Off) (shdr.sh_addralign - 1)));
904 306 : if (gelf_update_shdr (scn, &shdr) == 0)
905 : {
906 0 : error (0, 0, "couldn't update shdr: %s", elf_errmsg (-1));
907 0 : return 1;
908 : }
909 :
910 612 : GElf_Off filesz = (shdr.sh_type != SHT_NOBITS
911 306 : ? shdr.sh_size : 0);
912 306 : lastoffset = shdr.sh_offset + filesz;
913 306 : *last_offset = shdr.sh_offset;
914 306 : *last_size = filesz;
915 : }
916 : }
917 :
918 : return 0;
919 : }
920 :
921 : /* Maximum size of array allocated on stack. */
922 : #define MAX_STACK_ALLOC (400 * 1024)
923 :
924 : static int
925 113 : handle_elf (int fd, Elf *elf, const char *prefix, const char *fname,
926 : mode_t mode, struct timespec tvp[2])
927 : {
928 113 : size_t prefix_len = prefix == NULL ? 0 : strlen (prefix);
929 113 : size_t fname_len = strlen (fname) + 1;
930 113 : char *fullname = alloca (prefix_len + 1 + fname_len);
931 113 : char *cp = fullname;
932 113 : Elf *debugelf = NULL;
933 113 : tmp_debug_fname = NULL;
934 113 : int result = 0;
935 113 : size_t shdridx = 0;
936 113 : GElf_Off lastsec_offset = 0;
937 113 : Elf64_Xword lastsec_size = 0;
938 113 : size_t shstrndx;
939 113 : struct shdr_info
940 : {
941 : Elf_Scn *scn;
942 : GElf_Shdr shdr;
943 : Elf_Data *data;
944 : Elf_Data *debug_data;
945 : const char *name;
946 : Elf32_Word idx; /* Index in new file. */
947 : Elf32_Word old_sh_link; /* Original value of shdr.sh_link. */
948 : Elf32_Word symtab_idx;
949 : Elf32_Word version_idx;
950 : Elf32_Word group_idx;
951 : Elf32_Word group_cnt;
952 : Elf_Scn *newscn;
953 : Dwelf_Strent *se;
954 : Elf32_Word *newsymidx;
955 113 : } *shdr_info = NULL;
956 113 : Elf_Scn *scn;
957 113 : size_t cnt;
958 113 : size_t idx;
959 113 : bool changes;
960 113 : GElf_Ehdr newehdr_mem;
961 113 : GElf_Ehdr *newehdr;
962 113 : GElf_Ehdr debugehdr_mem;
963 113 : GElf_Ehdr *debugehdr;
964 113 : Dwelf_Strtab *shst = NULL;
965 113 : Elf_Data debuglink_crc_data;
966 113 : bool any_symtab_changes = false;
967 113 : Elf_Data *shstrtab_data = NULL;
968 113 : void *debuglink_buf = NULL;
969 :
970 : /* Create the full name of the file. */
971 113 : if (prefix != NULL)
972 : {
973 0 : cp = mempcpy (cp, prefix, prefix_len);
974 0 : *cp++ = ':';
975 : }
976 113 : memcpy (cp, fname, fname_len);
977 :
978 : /* If we are not replacing the input file open a new file here. */
979 113 : if (output_fname != NULL)
980 : {
981 81 : fd = open (output_fname, O_RDWR | O_CREAT, mode);
982 81 : if (unlikely (fd == -1))
983 : {
984 0 : error (0, errno, gettext ("cannot open '%s'"), output_fname);
985 0 : return 1;
986 : }
987 : }
988 :
989 113 : debug_fd = -1;
990 :
991 : /* Get the EBL handling. Removing all debugging symbols with the -g
992 : option or resolving all relocations between debug sections with
993 : the --reloc-debug-sections option are currently the only reasons
994 : we need EBL so don't open the backend unless necessary. */
995 113 : Ebl *ebl = NULL;
996 113 : if (remove_debug || reloc_debug || reloc_debug_only)
997 : {
998 56 : ebl = ebl_openbackend (elf);
999 56 : if (ebl == NULL)
1000 : {
1001 0 : error (0, errno, gettext ("cannot open EBL backend"));
1002 0 : result = 1;
1003 0 : goto fail;
1004 : }
1005 : }
1006 :
1007 : /* Open the additional file the debug information will be stored in. */
1008 113 : if (debug_fname != NULL)
1009 : {
1010 : /* Create a temporary file name. We do not want to overwrite
1011 : the debug file if the file would not contain any
1012 : information. */
1013 62 : size_t debug_fname_len = strlen (debug_fname);
1014 62 : tmp_debug_fname = (char *) xmalloc (debug_fname_len + sizeof (".XXXXXX"));
1015 124 : strcpy (mempcpy (tmp_debug_fname, debug_fname, debug_fname_len),
1016 : ".XXXXXX");
1017 :
1018 62 : debug_fd = mkstemp (tmp_debug_fname);
1019 62 : if (unlikely (debug_fd == -1))
1020 : {
1021 0 : error (0, errno, gettext ("cannot open '%s'"), debug_fname);
1022 0 : result = 1;
1023 0 : goto fail;
1024 : }
1025 : }
1026 :
1027 : /* Get the information from the old file. */
1028 113 : GElf_Ehdr ehdr_mem;
1029 113 : GElf_Ehdr *ehdr = gelf_getehdr (elf, &ehdr_mem);
1030 113 : if (ehdr == NULL)
1031 0 : INTERNAL_ERROR (fname);
1032 :
1033 : /* Get the section header string table index. */
1034 113 : if (unlikely (elf_getshdrstrndx (elf, &shstrndx) < 0))
1035 : {
1036 0 : cleanup_debug ();
1037 0 : error (EXIT_FAILURE, 0,
1038 0 : gettext ("cannot get section header string table index"));
1039 : }
1040 :
1041 : /* Get the number of phdrs in the old file. */
1042 113 : size_t phnum;
1043 113 : if (elf_getphdrnum (elf, &phnum) != 0)
1044 : {
1045 0 : cleanup_debug ();
1046 0 : error (EXIT_FAILURE, 0, gettext ("cannot get number of phdrs"));
1047 : }
1048 :
1049 : /* We now create a new ELF descriptor for the same file. We
1050 : construct it almost exactly in the same way with some information
1051 : dropped. */
1052 113 : Elf *newelf;
1053 113 : if (output_fname != NULL)
1054 81 : newelf = elf_begin (fd, ELF_C_WRITE_MMAP, NULL);
1055 : else
1056 32 : newelf = elf_clone (elf, ELF_C_EMPTY);
1057 :
1058 113 : if (unlikely (gelf_newehdr (newelf, gelf_getclass (elf)) == 0))
1059 : {
1060 0 : error (0, 0, gettext ("cannot create new ehdr for file '%s': %s"),
1061 0 : output_fname ?: fname, elf_errmsg (-1));
1062 0 : goto fail;
1063 : }
1064 :
1065 : /* Copy over the old program header if needed. */
1066 113 : if (phnum > 0)
1067 : {
1068 56 : if (unlikely (gelf_newphdr (newelf, phnum) == 0))
1069 : {
1070 0 : error (0, 0, gettext ("cannot create new phdr for file '%s': %s"),
1071 0 : output_fname ?: fname, elf_errmsg (-1));
1072 0 : goto fail;
1073 : }
1074 :
1075 477 : for (cnt = 0; cnt < phnum; ++cnt)
1076 : {
1077 421 : GElf_Phdr phdr_mem;
1078 421 : GElf_Phdr *phdr = gelf_getphdr (elf, cnt, &phdr_mem);
1079 421 : if (phdr == NULL
1080 421 : || unlikely (gelf_update_phdr (newelf, cnt, phdr) == 0))
1081 0 : INTERNAL_ERROR (fname);
1082 : }
1083 : }
1084 :
1085 113 : if (reloc_debug_only)
1086 : {
1087 15 : if (handle_debug_relocs (elf, ebl, newelf, ehdr, fname, shstrndx,
1088 : &lastsec_offset, &lastsec_size) != 0)
1089 : {
1090 : result = 1;
1091 : goto fail_close;
1092 : }
1093 15 : idx = shstrndx;
1094 15 : goto done; /* Skip all actual stripping operations. */
1095 : }
1096 :
1097 98 : if (debug_fname != NULL)
1098 : {
1099 : /* Also create an ELF descriptor for the debug file */
1100 62 : debugelf = elf_begin (debug_fd, ELF_C_WRITE, NULL);
1101 62 : if (unlikely (gelf_newehdr (debugelf, gelf_getclass (elf)) == 0))
1102 : {
1103 0 : error (0, 0, gettext ("cannot create new ehdr for file '%s': %s"),
1104 : debug_fname, elf_errmsg (-1));
1105 0 : goto fail_close;
1106 : }
1107 :
1108 : /* Copy over the old program header if needed. */
1109 62 : if (phnum > 0)
1110 : {
1111 26 : if (unlikely (gelf_newphdr (debugelf, phnum) == 0))
1112 : {
1113 0 : error (0, 0, gettext ("cannot create new phdr for file '%s': %s"),
1114 : debug_fname, elf_errmsg (-1));
1115 0 : goto fail_close;
1116 : }
1117 :
1118 221 : for (cnt = 0; cnt < phnum; ++cnt)
1119 : {
1120 195 : GElf_Phdr phdr_mem;
1121 195 : GElf_Phdr *phdr = gelf_getphdr (elf, cnt, &phdr_mem);
1122 195 : if (phdr == NULL
1123 195 : || unlikely (gelf_update_phdr (debugelf, cnt, phdr) == 0))
1124 0 : INTERNAL_ERROR (fname);
1125 : }
1126 : }
1127 : }
1128 :
1129 : /* Number of sections. */
1130 98 : size_t shnum;
1131 98 : if (unlikely (elf_getshdrnum (elf, &shnum) < 0))
1132 : {
1133 0 : error (0, 0, gettext ("cannot determine number of sections: %s"),
1134 : elf_errmsg (-1));
1135 0 : goto fail_close;
1136 : }
1137 :
1138 98 : if (shstrndx >= shnum)
1139 : goto illformed;
1140 :
1141 : #define elf_assert(test) do { if (!(test)) goto illformed; } while (0)
1142 :
1143 : /* Storage for section information. We leave room for two more
1144 : entries since we unconditionally create a section header string
1145 : table. Maybe some weird tool created an ELF file without one.
1146 : The other one is used for the debug link section. */
1147 98 : if ((shnum + 2) * sizeof (struct shdr_info) > MAX_STACK_ALLOC)
1148 3 : shdr_info = (struct shdr_info *) xcalloc (shnum + 2,
1149 : sizeof (struct shdr_info));
1150 : else
1151 : {
1152 95 : shdr_info = (struct shdr_info *) alloca ((shnum + 2)
1153 : * sizeof (struct shdr_info));
1154 95 : memset (shdr_info, '\0', (shnum + 2) * sizeof (struct shdr_info));
1155 : }
1156 :
1157 : /* Track whether allocated sections all come before non-allocated ones. */
1158 98 : bool seen_allocated = false;
1159 98 : bool seen_unallocated = false;
1160 98 : bool mixed_allocated_unallocated = false;
1161 :
1162 : /* Prepare section information data structure. */
1163 98 : scn = NULL;
1164 98 : cnt = 1;
1165 199748 : while ((scn = elf_nextscn (elf, scn)) != NULL)
1166 : {
1167 : /* This should always be true (i.e., there should not be any
1168 : holes in the numbering). */
1169 199650 : elf_assert (elf_ndxscn (scn) == cnt);
1170 :
1171 199650 : shdr_info[cnt].scn = scn;
1172 :
1173 : /* Get the header. */
1174 199650 : if (gelf_getshdr (scn, &shdr_info[cnt].shdr) == NULL)
1175 0 : INTERNAL_ERROR (fname);
1176 :
1177 : /* Normally (in non-ET_REL files) we see all allocated sections first,
1178 : then all non-allocated. */
1179 199650 : if ((shdr_info[cnt].shdr.sh_flags & SHF_ALLOC) == 0)
1180 : seen_unallocated = true;
1181 : else
1182 : {
1183 1604 : if (seen_unallocated && seen_allocated)
1184 290 : mixed_allocated_unallocated = true;
1185 : seen_allocated = true;
1186 : }
1187 :
1188 : /* Get the name of the section. */
1189 598950 : shdr_info[cnt].name = elf_strptr (elf, shstrndx,
1190 199650 : shdr_info[cnt].shdr.sh_name);
1191 199650 : if (shdr_info[cnt].name == NULL)
1192 : {
1193 0 : illformed:
1194 0 : error (0, 0, gettext ("illformed file '%s'"), fname);
1195 0 : goto fail_close;
1196 : }
1197 :
1198 : /* Sanity check the user. */
1199 399300 : if (section_name_matches (remove_secs, shdr_info[cnt].name))
1200 : {
1201 6 : if ((shdr_info[cnt].shdr.sh_flags & SHF_ALLOC) != 0)
1202 : {
1203 0 : error (0, 0,
1204 0 : gettext ("Cannot remove allocated section '%s'"),
1205 : shdr_info[cnt].name);
1206 0 : result = 1;
1207 0 : goto fail_close;
1208 : }
1209 :
1210 12 : if (section_name_matches (keep_secs, shdr_info[cnt].name))
1211 : {
1212 0 : error (0, 0,
1213 0 : gettext ("Cannot both keep and remove section '%s'"),
1214 0 : shdr_info[cnt].name);
1215 0 : result = 1;
1216 0 : goto fail_close;
1217 : }
1218 : }
1219 :
1220 : /* Mark them as present but not yet investigated. */
1221 199650 : shdr_info[cnt].idx = 1;
1222 :
1223 : /* Remember the shdr.sh_link value. */
1224 199650 : shdr_info[cnt].old_sh_link = shdr_info[cnt].shdr.sh_link;
1225 199650 : if (shdr_info[cnt].old_sh_link >= shnum)
1226 : goto illformed;
1227 :
1228 : /* Sections in files other than relocatable object files which
1229 : not loaded can be freely moved by us. In theory we can also
1230 : freely move around allocated nobits sections. But we don't
1231 : to keep the layout of all allocated sections as similar as
1232 : possible to the original file. In relocatable object files
1233 : everything can be moved. */
1234 199650 : if (phnum == 0
1235 198399 : || (shdr_info[cnt].shdr.sh_flags & SHF_ALLOC) == 0)
1236 198407 : shdr_info[cnt].shdr.sh_offset = 0;
1237 :
1238 : /* If this is an extended section index table store an
1239 : appropriate reference. */
1240 199650 : if (unlikely (shdr_info[cnt].shdr.sh_type == SHT_SYMTAB_SHNDX))
1241 : {
1242 0 : elf_assert (shdr_info[shdr_info[cnt].shdr.sh_link].symtab_idx == 0);
1243 0 : shdr_info[shdr_info[cnt].shdr.sh_link].symtab_idx = cnt;
1244 : }
1245 199650 : else if (unlikely (shdr_info[cnt].shdr.sh_type == SHT_GROUP))
1246 : {
1247 : /* Cross-reference the sections contained in the section
1248 : group. */
1249 10 : shdr_info[cnt].data = elf_getdata (shdr_info[cnt].scn, NULL);
1250 10 : if (shdr_info[cnt].data == NULL
1251 10 : || shdr_info[cnt].data->d_size < sizeof (Elf32_Word))
1252 0 : INTERNAL_ERROR (fname);
1253 :
1254 : /* XXX Fix for unaligned access. */
1255 10 : Elf32_Word *grpref = (Elf32_Word *) shdr_info[cnt].data->d_buf;
1256 10 : size_t inner;
1257 10 : for (inner = 1;
1258 28 : inner < shdr_info[cnt].data->d_size / sizeof (Elf32_Word);
1259 18 : ++inner)
1260 : {
1261 18 : if (grpref[inner] < shnum)
1262 18 : shdr_info[grpref[inner]].group_idx = cnt;
1263 : else
1264 : goto illformed;
1265 : }
1266 :
1267 10 : if (inner == 1 || (inner == 2 && (grpref[0] & GRP_COMDAT) == 0))
1268 : /* If the section group contains only one element and this
1269 : is n COMDAT section we can drop it right away. */
1270 2 : shdr_info[cnt].idx = 0;
1271 : else
1272 8 : shdr_info[cnt].group_cnt = inner - 1;
1273 : }
1274 199640 : else if (unlikely (shdr_info[cnt].shdr.sh_type == SHT_GNU_versym))
1275 : {
1276 54 : elf_assert (shdr_info[shdr_info[cnt].shdr.sh_link].version_idx == 0);
1277 54 : shdr_info[shdr_info[cnt].shdr.sh_link].version_idx = cnt;
1278 : }
1279 :
1280 : /* If this section is part of a group make sure it is not
1281 : discarded right away. */
1282 199650 : if ((shdr_info[cnt].shdr.sh_flags & SHF_GROUP) != 0)
1283 : {
1284 18 : elf_assert (shdr_info[cnt].group_idx != 0);
1285 :
1286 18 : if (shdr_info[shdr_info[cnt].group_idx].idx == 0)
1287 : {
1288 : /* The section group section might be removed.
1289 : Don't remove the SHF_GROUP flag. The section is
1290 : either also removed, in which case the flag doesn't matter.
1291 : Or it moves with the group into the debug file, then
1292 : it will be reconnected with the new group and should
1293 : still have the flag set. */
1294 2 : shdr_info[cnt].group_idx = 0;
1295 : }
1296 : }
1297 :
1298 : /* Increment the counter. */
1299 199650 : ++cnt;
1300 : }
1301 :
1302 : /* Now determine which sections can go away. The general rule is that
1303 : all sections which are not used at runtime are stripped out. But
1304 : there are a few exceptions:
1305 :
1306 : - special sections named ".comment" and ".note" are kept
1307 : - OS or architecture specific sections are kept since we might not
1308 : know how to handle them
1309 : - if a section is referred to from a section which is not removed
1310 : in the sh_link or sh_info element it cannot be removed either
1311 : - the user might have explicitly said to remove or keep a section
1312 : */
1313 199748 : for (cnt = 1; cnt < shnum; ++cnt)
1314 : /* Check whether the section can be removed. Since we will create
1315 : a new .shstrtab assume it will be removed too. */
1316 399300 : if (remove_shdrs ? !(shdr_info[cnt].shdr.sh_flags & SHF_ALLOC)
1317 399300 : : (ebl_section_strip_p (ebl, &shdr_info[cnt].shdr,
1318 199650 : shdr_info[cnt].name, remove_comment,
1319 : remove_debug)
1320 67335 : || cnt == shstrndx
1321 334268 : || section_name_matches (remove_secs, shdr_info[cnt].name)))
1322 : {
1323 : /* The user might want to explicitly keep this one. */
1324 264694 : if (section_name_matches (keep_secs, shdr_info[cnt].name))
1325 : continue;
1326 :
1327 : /* For now assume this section will be removed. */
1328 132341 : shdr_info[cnt].idx = 0;
1329 :
1330 132341 : idx = shdr_info[cnt].group_idx;
1331 132342 : while (idx != 0)
1332 : {
1333 : /* The section group data is already loaded. */
1334 5 : elf_assert (shdr_info[idx].data != NULL
1335 : && shdr_info[idx].data->d_buf != NULL
1336 : && shdr_info[idx].data->d_size >= sizeof (Elf32_Word));
1337 :
1338 : /* If the references section group is a normal section
1339 : group and has one element remaining, or if it is an
1340 : empty COMDAT section group it is removed. */
1341 10 : bool is_comdat = (((Elf32_Word *) shdr_info[idx].data->d_buf)[0]
1342 5 : & GRP_COMDAT) != 0;
1343 :
1344 5 : --shdr_info[idx].group_cnt;
1345 5 : if ((!is_comdat && shdr_info[idx].group_cnt == 1)
1346 5 : || (is_comdat && shdr_info[idx].group_cnt == 0))
1347 : {
1348 1 : shdr_info[idx].idx = 0;
1349 : /* Continue recursively. */
1350 1 : idx = shdr_info[idx].group_idx;
1351 : }
1352 : else
1353 : break;
1354 : }
1355 : }
1356 :
1357 : /* Mark the SHT_NULL section as handled. */
1358 98 : shdr_info[0].idx = 2;
1359 :
1360 :
1361 : /* Handle exceptions: section groups and cross-references. We might
1362 : have to repeat this a few times since the resetting of the flag
1363 : might propagate. */
1364 98 : do
1365 : {
1366 98 : changes = false;
1367 :
1368 199748 : for (cnt = 1; cnt < shnum; ++cnt)
1369 : {
1370 199650 : if (shdr_info[cnt].idx == 0)
1371 : {
1372 : /* If a relocation section is marked as being removed make
1373 : sure the section it is relocating is removed, too. */
1374 264518 : if (shdr_info[cnt].shdr.sh_type == SHT_REL
1375 132259 : || shdr_info[cnt].shdr.sh_type == SHT_RELA)
1376 : {
1377 363 : if (shdr_info[cnt].shdr.sh_info >= shnum)
1378 : goto illformed;
1379 363 : else if (shdr_info[shdr_info[cnt].shdr.sh_info].idx != 0)
1380 163 : shdr_info[cnt].idx = 1;
1381 : }
1382 :
1383 : /* If a group section is marked as being removed make
1384 : sure all the sections it contains are being removed, too. */
1385 132259 : if (shdr_info[cnt].shdr.sh_type == SHT_GROUP)
1386 : {
1387 10 : Elf32_Word *grpref;
1388 10 : grpref = (Elf32_Word *) shdr_info[cnt].data->d_buf;
1389 10 : for (size_t in = 1;
1390 11 : in < shdr_info[cnt].data->d_size / sizeof (Elf32_Word);
1391 1 : ++in)
1392 10 : if (grpref[in] < shnum)
1393 : {
1394 10 : if (shdr_info[grpref[in]].idx != 0)
1395 : {
1396 9 : shdr_info[cnt].idx = 1;
1397 9 : break;
1398 : }
1399 : }
1400 : else
1401 : goto illformed;
1402 : }
1403 : }
1404 :
1405 199650 : if (shdr_info[cnt].idx == 1)
1406 : {
1407 : /* The content of symbol tables we don't remove must not
1408 : reference any section which we do remove. Otherwise
1409 : we cannot remove the section. */
1410 67563 : if (debug_fname != NULL
1411 66764 : && shdr_info[cnt].debug_data == NULL
1412 133380 : && (shdr_info[cnt].shdr.sh_type == SHT_DYNSYM
1413 66690 : || shdr_info[cnt].shdr.sh_type == SHT_SYMTAB))
1414 : {
1415 : /* Make sure the data is loaded. */
1416 33 : if (shdr_info[cnt].data == NULL)
1417 : {
1418 33 : shdr_info[cnt].data
1419 33 : = elf_getdata (shdr_info[cnt].scn, NULL);
1420 33 : if (shdr_info[cnt].data == NULL)
1421 0 : INTERNAL_ERROR (fname);
1422 : }
1423 33 : Elf_Data *symdata = shdr_info[cnt].data;
1424 :
1425 : /* If there is an extended section index table load it
1426 : as well. */
1427 33 : if (shdr_info[cnt].symtab_idx != 0
1428 0 : && shdr_info[shdr_info[cnt].symtab_idx].data == NULL)
1429 : {
1430 0 : elf_assert (shdr_info[cnt].shdr.sh_type == SHT_SYMTAB);
1431 :
1432 0 : shdr_info[shdr_info[cnt].symtab_idx].data
1433 0 : = elf_getdata (shdr_info[shdr_info[cnt].symtab_idx].scn,
1434 : NULL);
1435 0 : if (shdr_info[shdr_info[cnt].symtab_idx].data == NULL)
1436 0 : INTERNAL_ERROR (fname);
1437 : }
1438 66 : Elf_Data *xndxdata
1439 33 : = shdr_info[shdr_info[cnt].symtab_idx].data;
1440 :
1441 : /* Go through all symbols and make sure the section they
1442 : reference is not removed. */
1443 33 : size_t elsize = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
1444 :
1445 33 : for (size_t inner = 0;
1446 1178 : inner < shdr_info[cnt].data->d_size / elsize;
1447 1145 : ++inner)
1448 : {
1449 1145 : GElf_Sym sym_mem;
1450 1145 : Elf32_Word xndx;
1451 1145 : GElf_Sym *sym = gelf_getsymshndx (symdata, xndxdata,
1452 : inner, &sym_mem,
1453 : &xndx);
1454 1145 : if (sym == NULL)
1455 0 : INTERNAL_ERROR (fname);
1456 :
1457 1145 : size_t scnidx = sym->st_shndx;
1458 1145 : if (scnidx == SHN_UNDEF || scnidx >= shnum
1459 622 : || (scnidx >= SHN_LORESERVE
1460 : && scnidx <= SHN_HIRESERVE
1461 622 : && scnidx != SHN_XINDEX)
1462 : /* Don't count in the section symbols. */
1463 611 : || GELF_ST_TYPE (sym->st_info) == STT_SECTION)
1464 : /* This is no section index, leave it alone. */
1465 793 : continue;
1466 352 : else if (scnidx == SHN_XINDEX)
1467 0 : scnidx = xndx;
1468 :
1469 352 : if (scnidx >= shnum)
1470 0 : goto illformed;
1471 :
1472 352 : if (shdr_info[scnidx].idx == 0)
1473 : /* This symbol table has a real symbol in
1474 : a discarded section. So preserve the
1475 : original table in the debug file. Unless
1476 : it is a redundant data marker to a debug
1477 : (data only) section. */
1478 8 : if (! (ebl_section_strip_p (ebl,
1479 4 : &shdr_info[scnidx].shdr,
1480 : shdr_info[scnidx].name,
1481 : remove_comment,
1482 : remove_debug)
1483 4 : && ebl_data_marker_symbol (ebl, sym,
1484 8 : elf_strptr (elf,
1485 4 : shdr_info[cnt].shdr.sh_link,
1486 4 : sym->st_name))))
1487 0 : shdr_info[cnt].debug_data = symdata;
1488 : }
1489 : }
1490 :
1491 : /* Cross referencing happens:
1492 : - for the cases the ELF specification says. That are
1493 : + SHT_DYNAMIC in sh_link to string table
1494 : + SHT_HASH in sh_link to symbol table
1495 : + SHT_REL and SHT_RELA in sh_link to symbol table
1496 : + SHT_SYMTAB and SHT_DYNSYM in sh_link to string table
1497 : + SHT_GROUP in sh_link to symbol table
1498 : + SHT_SYMTAB_SHNDX in sh_link to symbol table
1499 : Other (OS or architecture-specific) sections might as
1500 : well use this field so we process it unconditionally.
1501 : - references inside section groups
1502 : - specially marked references in sh_info if the SHF_INFO_LINK
1503 : flag is set
1504 : */
1505 :
1506 67563 : if (shdr_info[shdr_info[cnt].shdr.sh_link].idx == 0)
1507 : {
1508 82 : shdr_info[shdr_info[cnt].shdr.sh_link].idx = 1;
1509 82 : changes |= shdr_info[cnt].shdr.sh_link < cnt;
1510 : }
1511 :
1512 : /* Handle references through sh_info. */
1513 67563 : if (SH_INFO_LINK_P (&shdr_info[cnt].shdr))
1514 : {
1515 269 : if (shdr_info[cnt].shdr.sh_info >= shnum)
1516 : goto illformed;
1517 269 : else if ( shdr_info[shdr_info[cnt].shdr.sh_info].idx == 0)
1518 : {
1519 0 : shdr_info[shdr_info[cnt].shdr.sh_info].idx = 1;
1520 0 : changes |= shdr_info[cnt].shdr.sh_info < cnt;
1521 : }
1522 : }
1523 :
1524 : /* Mark the section as investigated. */
1525 67563 : shdr_info[cnt].idx = 2;
1526 : }
1527 :
1528 199650 : if (debug_fname != NULL
1529 132962 : && (shdr_info[cnt].idx == 0 || shdr_info[cnt].debug_data != NULL))
1530 : {
1531 : /* This section is being preserved in the debug file.
1532 : Sections it refers to must be preserved there too.
1533 :
1534 : In this pass we mark sections to be preserved in both
1535 : files by setting the .debug_data pointer to the original
1536 : file's .data pointer. Below, we'll copy the section
1537 : contents. */
1538 :
1539 132709 : inline void check_preserved (size_t i)
1540 : {
1541 66437 : if (i != 0 && i < shnum + 2 && shdr_info[i].idx != 0
1542 205 : && shdr_info[i].debug_data == NULL)
1543 : {
1544 74 : if (shdr_info[i].data == NULL)
1545 74 : shdr_info[i].data = elf_getdata (shdr_info[i].scn, NULL);
1546 74 : if (shdr_info[i].data == NULL)
1547 0 : INTERNAL_ERROR (fname);
1548 :
1549 74 : shdr_info[i].debug_data = shdr_info[i].data;
1550 74 : changes |= i < cnt;
1551 : }
1552 66437 : }
1553 :
1554 66272 : check_preserved (shdr_info[cnt].shdr.sh_link);
1555 66272 : if (SH_INFO_LINK_P (&shdr_info[cnt].shdr))
1556 165 : check_preserved (shdr_info[cnt].shdr.sh_info);
1557 : }
1558 : }
1559 : }
1560 98 : while (changes);
1561 :
1562 : /* Copy the removed sections to the debug output file.
1563 : The ones that are not removed in the stripped file are SHT_NOBITS. */
1564 98 : if (debug_fname != NULL)
1565 : {
1566 133024 : for (cnt = 1; cnt < shnum; ++cnt)
1567 : {
1568 132962 : scn = elf_newscn (debugelf);
1569 132962 : if (scn == NULL)
1570 : {
1571 0 : cleanup_debug ();
1572 0 : error (EXIT_FAILURE, 0,
1573 0 : gettext ("while generating output file: %s"),
1574 : elf_errmsg (-1));
1575 : }
1576 :
1577 265924 : bool discard_section = (shdr_info[cnt].idx > 0
1578 66764 : && shdr_info[cnt].debug_data == NULL
1579 66690 : && shdr_info[cnt].shdr.sh_type != SHT_NOTE
1580 66621 : && shdr_info[cnt].shdr.sh_type != SHT_GROUP
1581 199574 : && cnt != shstrndx);
1582 :
1583 : /* Set the section header in the new file. */
1584 132962 : GElf_Shdr debugshdr = shdr_info[cnt].shdr;
1585 132962 : if (discard_section)
1586 66612 : debugshdr.sh_type = SHT_NOBITS;
1587 :
1588 132962 : if (unlikely (gelf_update_shdr (scn, &debugshdr) == 0))
1589 : /* There cannot be any overflows. */
1590 0 : INTERNAL_ERROR (fname);
1591 :
1592 : /* Get the data from the old file if necessary. */
1593 132962 : if (shdr_info[cnt].data == NULL)
1594 : {
1595 132845 : shdr_info[cnt].data = elf_getdata (shdr_info[cnt].scn, NULL);
1596 132845 : if (shdr_info[cnt].data == NULL)
1597 0 : INTERNAL_ERROR (fname);
1598 : }
1599 :
1600 : /* Set the data. This is done by copying from the old file. */
1601 132962 : Elf_Data *debugdata = elf_newdata (scn);
1602 132962 : if (debugdata == NULL)
1603 0 : INTERNAL_ERROR (fname);
1604 :
1605 : /* Copy the structure. This data may be modified in place
1606 : before we write out the file. */
1607 132962 : *debugdata = *shdr_info[cnt].data;
1608 132962 : if (discard_section)
1609 66612 : debugdata->d_buf = NULL;
1610 66350 : else if (shdr_info[cnt].debug_data != NULL
1611 66276 : || shdr_info[cnt].shdr.sh_type == SHT_GROUP)
1612 : {
1613 : /* Copy the original data before it gets modified. */
1614 84 : shdr_info[cnt].debug_data = debugdata;
1615 84 : if (debugdata->d_buf == NULL)
1616 0 : INTERNAL_ERROR (fname);
1617 84 : debugdata->d_buf = memcpy (xmalloc (debugdata->d_size),
1618 : debugdata->d_buf, debugdata->d_size);
1619 : }
1620 : }
1621 :
1622 : /* Finish the ELF header. Fill in the fields not handled by
1623 : libelf from the old file. */
1624 62 : debugehdr = gelf_getehdr (debugelf, &debugehdr_mem);
1625 62 : if (debugehdr == NULL)
1626 0 : INTERNAL_ERROR (fname);
1627 :
1628 62 : memcpy (debugehdr->e_ident, ehdr->e_ident, EI_NIDENT);
1629 62 : debugehdr->e_type = ehdr->e_type;
1630 62 : debugehdr->e_machine = ehdr->e_machine;
1631 62 : debugehdr->e_version = ehdr->e_version;
1632 62 : debugehdr->e_entry = ehdr->e_entry;
1633 62 : debugehdr->e_flags = ehdr->e_flags;
1634 :
1635 62 : if (unlikely (gelf_update_ehdr (debugelf, debugehdr) == 0))
1636 : {
1637 0 : error (0, 0, gettext ("%s: error while updating ELF header: %s"),
1638 : debug_fname, elf_errmsg (-1));
1639 0 : result = 1;
1640 0 : goto fail_close;
1641 : }
1642 :
1643 62 : size_t shdrstrndx;
1644 62 : if (elf_getshdrstrndx (elf, &shdrstrndx) < 0)
1645 : {
1646 0 : error (0, 0, gettext ("%s: error while getting shdrstrndx: %s"),
1647 : fname, elf_errmsg (-1));
1648 0 : result = 1;
1649 0 : goto fail_close;
1650 : }
1651 :
1652 62 : if (update_shdrstrndx (debugelf, shdrstrndx) != 0)
1653 : {
1654 0 : error (0, 0, gettext ("%s: error updating shdrstrndx: %s"),
1655 : debug_fname, elf_errmsg (-1));
1656 0 : result = 1;
1657 0 : goto fail_close;
1658 : }
1659 : }
1660 :
1661 : /* Although we always create a new section header string table we
1662 : don't explicitly mark the existing one as unused. It can still
1663 : be used through a symbol table section we are keeping. If not it
1664 : will already be marked as unused. */
1665 :
1666 : /* We need a string table for the section headers. */
1667 98 : shst = dwelf_strtab_init (true);
1668 98 : if (shst == NULL)
1669 : {
1670 0 : cleanup_debug ();
1671 0 : error (EXIT_FAILURE, errno, gettext ("while preparing output for '%s'"),
1672 0 : output_fname ?: fname);
1673 : }
1674 :
1675 : /* Assign new section numbers. */
1676 98 : shdr_info[0].idx = 0;
1677 199748 : for (cnt = idx = 1; cnt < shnum; ++cnt)
1678 199650 : if (shdr_info[cnt].idx > 0)
1679 : {
1680 67563 : shdr_info[cnt].idx = idx++;
1681 :
1682 : /* Create a new section. */
1683 67563 : shdr_info[cnt].newscn = elf_newscn (newelf);
1684 67563 : if (shdr_info[cnt].newscn == NULL)
1685 : {
1686 0 : cleanup_debug ();
1687 0 : error (EXIT_FAILURE, 0,
1688 0 : gettext ("while generating output file: %s"),
1689 : elf_errmsg (-1));
1690 : }
1691 :
1692 67563 : elf_assert (elf_ndxscn (shdr_info[cnt].newscn) == shdr_info[cnt].idx);
1693 :
1694 : /* Add this name to the section header string table. */
1695 67563 : shdr_info[cnt].se = dwelf_strtab_add (shst, shdr_info[cnt].name);
1696 : }
1697 :
1698 : /* Test whether we are doing anything at all. Either all removable
1699 : sections are already gone. Or the only section we would remove is
1700 : the .shstrtab section which we would add again. */
1701 98 : bool removing_sections = !(cnt == idx
1702 98 : || (cnt == idx + 1
1703 4 : && shdr_info[shstrndx].idx == 0));
1704 98 : if (output_fname == NULL && !removing_sections)
1705 : goto fail_close;
1706 :
1707 : /* Create the reference to the file with the debug info (if any). */
1708 96 : if (debug_fname != NULL && !remove_shdrs && removing_sections)
1709 : {
1710 : /* Add the section header string table section name. */
1711 60 : shdr_info[cnt].se = dwelf_strtab_add_len (shst, ".gnu_debuglink", 15);
1712 60 : shdr_info[cnt].idx = idx++;
1713 :
1714 : /* Create the section header. */
1715 60 : shdr_info[cnt].shdr.sh_type = SHT_PROGBITS;
1716 60 : shdr_info[cnt].shdr.sh_flags = 0;
1717 60 : shdr_info[cnt].shdr.sh_addr = 0;
1718 60 : shdr_info[cnt].shdr.sh_link = SHN_UNDEF;
1719 60 : shdr_info[cnt].shdr.sh_info = SHN_UNDEF;
1720 60 : shdr_info[cnt].shdr.sh_entsize = 0;
1721 60 : shdr_info[cnt].shdr.sh_addralign = 4;
1722 : /* We set the offset to zero here. Before we write the ELF file the
1723 : field must have the correct value. This is done in the final
1724 : loop over all section. Then we have all the information needed. */
1725 60 : shdr_info[cnt].shdr.sh_offset = 0;
1726 :
1727 : /* Create the section. */
1728 60 : shdr_info[cnt].newscn = elf_newscn (newelf);
1729 60 : if (shdr_info[cnt].newscn == NULL)
1730 : {
1731 0 : cleanup_debug ();
1732 0 : error (EXIT_FAILURE, 0,
1733 0 : gettext ("while create section header section: %s"),
1734 : elf_errmsg (-1));
1735 : }
1736 60 : elf_assert (elf_ndxscn (shdr_info[cnt].newscn) == shdr_info[cnt].idx);
1737 :
1738 60 : shdr_info[cnt].data = elf_newdata (shdr_info[cnt].newscn);
1739 60 : if (shdr_info[cnt].data == NULL)
1740 : {
1741 0 : cleanup_debug ();
1742 0 : error (EXIT_FAILURE, 0, gettext ("cannot allocate section data: %s"),
1743 : elf_errmsg (-1));
1744 : }
1745 :
1746 60 : char *debug_basename = basename (debug_fname_embed ?: debug_fname);
1747 60 : off_t crc_offset = strlen (debug_basename) + 1;
1748 : /* Align to 4 byte boundary */
1749 60 : crc_offset = ((crc_offset - 1) & ~3) + 4;
1750 :
1751 60 : shdr_info[cnt].data->d_align = 4;
1752 120 : shdr_info[cnt].shdr.sh_size = shdr_info[cnt].data->d_size
1753 60 : = crc_offset + 4;
1754 60 : debuglink_buf = xcalloc (1, shdr_info[cnt].data->d_size);
1755 60 : shdr_info[cnt].data->d_buf = debuglink_buf;
1756 :
1757 60 : strcpy (shdr_info[cnt].data->d_buf, debug_basename);
1758 :
1759 : /* Cache this Elf_Data describing the CRC32 word in the section.
1760 : We'll fill this in when we have written the debug file. */
1761 60 : debuglink_crc_data = *shdr_info[cnt].data;
1762 120 : debuglink_crc_data.d_buf = ((char *) debuglink_crc_data.d_buf
1763 60 : + crc_offset);
1764 60 : debuglink_crc_data.d_size = 4;
1765 :
1766 : /* One more section done. */
1767 60 : ++cnt;
1768 : }
1769 :
1770 : /* Index of the section header table in the shdr_info array. */
1771 96 : shdridx = cnt;
1772 :
1773 : /* Add the section header string table section name. */
1774 96 : shdr_info[cnt].se = dwelf_strtab_add_len (shst, ".shstrtab", 10);
1775 96 : shdr_info[cnt].idx = idx;
1776 :
1777 : /* Create the section header. */
1778 96 : shdr_info[cnt].shdr.sh_type = SHT_STRTAB;
1779 96 : shdr_info[cnt].shdr.sh_flags = 0;
1780 96 : shdr_info[cnt].shdr.sh_addr = 0;
1781 96 : shdr_info[cnt].shdr.sh_link = SHN_UNDEF;
1782 96 : shdr_info[cnt].shdr.sh_info = SHN_UNDEF;
1783 96 : shdr_info[cnt].shdr.sh_entsize = 0;
1784 : /* We set the offset to zero here. Before we write the ELF file the
1785 : field must have the correct value. This is done in the final
1786 : loop over all section. Then we have all the information needed. */
1787 96 : shdr_info[cnt].shdr.sh_offset = 0;
1788 96 : shdr_info[cnt].shdr.sh_addralign = 1;
1789 :
1790 : /* Create the section. */
1791 96 : shdr_info[cnt].newscn = elf_newscn (newelf);
1792 96 : if (shdr_info[cnt].newscn == NULL)
1793 : {
1794 0 : cleanup_debug ();
1795 0 : error (EXIT_FAILURE, 0,
1796 0 : gettext ("while create section header section: %s"),
1797 : elf_errmsg (-1));
1798 : }
1799 96 : elf_assert (elf_ndxscn (shdr_info[cnt].newscn) == idx);
1800 :
1801 : /* Finalize the string table and fill in the correct indices in the
1802 : section headers. */
1803 96 : shstrtab_data = elf_newdata (shdr_info[cnt].newscn);
1804 96 : if (shstrtab_data == NULL)
1805 : {
1806 0 : cleanup_debug ();
1807 0 : error (EXIT_FAILURE, 0,
1808 0 : gettext ("while create section header string table: %s"),
1809 : elf_errmsg (-1));
1810 : }
1811 96 : if (dwelf_strtab_finalize (shst, shstrtab_data) == NULL)
1812 : {
1813 0 : cleanup_debug ();
1814 0 : error (EXIT_FAILURE, 0,
1815 0 : gettext ("no memory to create section header string table"));
1816 : }
1817 :
1818 : /* We have to set the section size. */
1819 96 : shdr_info[cnt].shdr.sh_size = shstrtab_data->d_size;
1820 :
1821 : /* Update the section information. */
1822 96 : GElf_Off lastoffset = 0;
1823 199850 : for (cnt = 1; cnt <= shdridx; ++cnt)
1824 199754 : if (shdr_info[cnt].idx > 0)
1825 : {
1826 67669 : Elf_Data *newdata;
1827 :
1828 67669 : scn = elf_getscn (newelf, shdr_info[cnt].idx);
1829 67669 : elf_assert (scn != NULL);
1830 :
1831 : /* Update the name. */
1832 67669 : shdr_info[cnt].shdr.sh_name = dwelf_strent_off (shdr_info[cnt].se);
1833 :
1834 : /* Update the section header from the input file. Some fields
1835 : might be section indeces which now have to be adjusted. Keep
1836 : the index to the "current" sh_link in case we need it to lookup
1837 : symbol table names. */
1838 67669 : size_t sh_link = shdr_info[cnt].shdr.sh_link;
1839 67669 : if (shdr_info[cnt].shdr.sh_link != 0)
1840 1208 : shdr_info[cnt].shdr.sh_link =
1841 604 : shdr_info[shdr_info[cnt].shdr.sh_link].idx;
1842 :
1843 67669 : if (shdr_info[cnt].shdr.sh_type == SHT_GROUP)
1844 : {
1845 9 : elf_assert (shdr_info[cnt].data != NULL
1846 : && shdr_info[cnt].data->d_buf != NULL);
1847 :
1848 : Elf32_Word *grpref = (Elf32_Word *) shdr_info[cnt].data->d_buf;
1849 : /* First word is the section group flag.
1850 : Followed by section indexes, that need to be renumbered. */
1851 26 : for (size_t inner = 1;
1852 26 : inner < shdr_info[cnt].data->d_size / sizeof (Elf32_Word);
1853 17 : ++inner)
1854 17 : if (grpref[inner] < shnum)
1855 17 : grpref[inner] = shdr_info[grpref[inner]].idx;
1856 : else
1857 : goto illformed;
1858 : }
1859 :
1860 : /* Handle the SHT_REL, SHT_RELA, and SHF_INFO_LINK flag. */
1861 67669 : if (SH_INFO_LINK_P (&shdr_info[cnt].shdr))
1862 534 : shdr_info[cnt].shdr.sh_info =
1863 267 : shdr_info[shdr_info[cnt].shdr.sh_info].idx;
1864 :
1865 : /* Get the data from the old file if necessary. We already
1866 : created the data for the section header string table. */
1867 67669 : if (cnt < shnum)
1868 : {
1869 67513 : if (shdr_info[cnt].data == NULL)
1870 : {
1871 774 : shdr_info[cnt].data = elf_getdata (shdr_info[cnt].scn, NULL);
1872 774 : if (shdr_info[cnt].data == NULL)
1873 0 : INTERNAL_ERROR (fname);
1874 : }
1875 :
1876 : /* Set the data. This is done by copying from the old file. */
1877 67513 : newdata = elf_newdata (scn);
1878 67513 : if (newdata == NULL)
1879 0 : INTERNAL_ERROR (fname);
1880 :
1881 : /* Copy the structure. */
1882 67513 : *newdata = *shdr_info[cnt].data;
1883 :
1884 : /* We know the size. */
1885 67513 : shdr_info[cnt].shdr.sh_size = shdr_info[cnt].data->d_size;
1886 :
1887 : /* We have to adjust symbol tables. The st_shndx member might
1888 : have to be updated. */
1889 135026 : if (shdr_info[cnt].shdr.sh_type == SHT_DYNSYM
1890 67513 : || shdr_info[cnt].shdr.sh_type == SHT_SYMTAB)
1891 : {
1892 112 : Elf_Data *versiondata = NULL;
1893 112 : Elf_Data *shndxdata = NULL;
1894 :
1895 112 : size_t elsize = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
1896 :
1897 112 : if (shdr_info[cnt].symtab_idx != 0)
1898 : {
1899 0 : elf_assert (shdr_info[cnt].shdr.sh_type == SHT_SYMTAB_SHNDX);
1900 : /* This section has extended section information.
1901 : We have to modify that information, too. */
1902 0 : shndxdata = elf_getdata (shdr_info[shdr_info[cnt].symtab_idx].scn,
1903 : NULL);
1904 :
1905 0 : elf_assert (shndxdata != NULL
1906 : && shndxdata->d_buf != NULL
1907 : && ((shndxdata->d_size / sizeof (Elf32_Word))
1908 : >= shdr_info[cnt].data->d_size / elsize));
1909 : }
1910 :
1911 112 : if (shdr_info[cnt].version_idx != 0)
1912 : {
1913 52 : elf_assert (shdr_info[cnt].shdr.sh_type == SHT_DYNSYM);
1914 : /* This section has associated version
1915 : information. We have to modify that
1916 : information, too. */
1917 52 : versiondata = elf_getdata (shdr_info[shdr_info[cnt].version_idx].scn,
1918 : NULL);
1919 :
1920 52 : elf_assert (versiondata != NULL
1921 : && versiondata->d_buf != NULL
1922 : && ((versiondata->d_size / sizeof (GElf_Versym))
1923 : >= shdr_info[cnt].data->d_size / elsize));
1924 : }
1925 :
1926 112 : shdr_info[cnt].newsymidx
1927 112 : = (Elf32_Word *) xcalloc (shdr_info[cnt].data->d_size
1928 : / elsize, sizeof (Elf32_Word));
1929 :
1930 112 : bool last_was_local = true;
1931 112 : size_t destidx;
1932 112 : size_t inner;
1933 112 : for (destidx = inner = 1;
1934 19334 : inner < shdr_info[cnt].data->d_size / elsize;
1935 19222 : ++inner)
1936 : {
1937 19222 : Elf32_Word sec;
1938 19222 : GElf_Sym sym_mem;
1939 19222 : Elf32_Word xshndx;
1940 19222 : GElf_Sym *sym = gelf_getsymshndx (shdr_info[cnt].data,
1941 : shndxdata, inner,
1942 : &sym_mem, &xshndx);
1943 19222 : if (sym == NULL)
1944 0 : INTERNAL_ERROR (fname);
1945 :
1946 38444 : if (sym->st_shndx == SHN_UNDEF
1947 19222 : || (sym->st_shndx >= SHN_LORESERVE
1948 : && sym->st_shndx != SHN_XINDEX))
1949 : {
1950 : /* This is no section index, leave it alone
1951 : unless it is moved. */
1952 1944 : if (destidx != inner
1953 1402 : && gelf_update_symshndx (shdr_info[cnt].data,
1954 : shndxdata,
1955 : destidx, sym,
1956 : xshndx) == 0)
1957 0 : INTERNAL_ERROR (fname);
1958 :
1959 1944 : shdr_info[cnt].newsymidx[inner] = destidx++;
1960 :
1961 1944 : if (last_was_local
1962 268 : && GELF_ST_BIND (sym->st_info) != STB_LOCAL)
1963 : {
1964 61 : last_was_local = false;
1965 61 : shdr_info[cnt].shdr.sh_info = destidx - 1;
1966 : }
1967 :
1968 1944 : continue;
1969 : }
1970 :
1971 : /* Get the full section index, if necessary from the
1972 : XINDEX table. */
1973 17278 : if (sym->st_shndx == SHN_XINDEX)
1974 0 : elf_assert (shndxdata != NULL
1975 : && shndxdata->d_buf != NULL);
1976 34556 : size_t sidx = (sym->st_shndx != SHN_XINDEX
1977 17278 : ? sym->st_shndx : xshndx);
1978 17278 : elf_assert (sidx < shnum);
1979 17278 : sec = shdr_info[sidx].idx;
1980 :
1981 17278 : if (sec != 0)
1982 : {
1983 2929 : GElf_Section nshndx;
1984 2929 : Elf32_Word nxshndx;
1985 :
1986 2929 : if (sec < SHN_LORESERVE)
1987 : {
1988 2929 : nshndx = sec;
1989 2929 : nxshndx = 0;
1990 : }
1991 : else
1992 : {
1993 : nshndx = SHN_XINDEX;
1994 : nxshndx = sec;
1995 : }
1996 :
1997 2929 : elf_assert (sec < SHN_LORESERVE || shndxdata != NULL);
1998 :
1999 2929 : if ((inner != destidx || nshndx != sym->st_shndx
2000 1465 : || (shndxdata != NULL && nxshndx != xshndx))
2001 1464 : && (sym->st_shndx = nshndx,
2002 1464 : gelf_update_symshndx (shdr_info[cnt].data,
2003 : shndxdata,
2004 : destidx, sym,
2005 : nxshndx) == 0))
2006 0 : INTERNAL_ERROR (fname);
2007 :
2008 2929 : shdr_info[cnt].newsymidx[inner] = destidx++;
2009 :
2010 2929 : if (last_was_local
2011 2489 : && GELF_ST_BIND (sym->st_info) != STB_LOCAL)
2012 : {
2013 51 : last_was_local = false;
2014 51 : shdr_info[cnt].shdr.sh_info = destidx - 1;
2015 : }
2016 : }
2017 14349 : else if ((shdr_info[cnt].shdr.sh_flags & SHF_ALLOC) != 0
2018 48 : && GELF_ST_TYPE (sym->st_info) != STT_SECTION
2019 0 : && shdr_info[sidx].shdr.sh_type != SHT_GROUP)
2020 : {
2021 : /* Removing a real symbol from an allocated
2022 : symbol table is hard and probably a
2023 : mistake. Really removing it means
2024 : rewriting the dynamic segment and hash
2025 : sections. Just warn and set the symbol
2026 : section to UNDEF. */
2027 0 : error (0, 0,
2028 0 : gettext ("Cannot remove symbol [%zd] from allocated symbol table [%zd]"), inner, cnt);
2029 0 : sym->st_shndx = SHN_UNDEF;
2030 0 : if (gelf_update_sym (shdr_info[cnt].data, destidx,
2031 : sym) == 0)
2032 0 : INTERNAL_ERROR (fname);
2033 0 : shdr_info[cnt].newsymidx[inner] = destidx++;
2034 : }
2035 14349 : else if (debug_fname != NULL
2036 14171 : && shdr_info[cnt].debug_data == NULL)
2037 : /* The symbol points to a section that is discarded
2038 : but isn't preserved in the debug file. Check that
2039 : this is a section or group signature symbol
2040 : for a section which has been removed. Or a special
2041 : data marker symbol to a debug section. */
2042 : {
2043 55 : elf_assert (GELF_ST_TYPE (sym->st_info) == STT_SECTION
2044 : || ((shdr_info[sidx].shdr.sh_type
2045 : == SHT_GROUP)
2046 : && (shdr_info[sidx].shdr.sh_info
2047 : == inner))
2048 : || ebl_data_marker_symbol (ebl, sym,
2049 : elf_strptr (elf, sh_link,
2050 : sym->st_name)));
2051 : }
2052 : }
2053 :
2054 112 : if (destidx != inner)
2055 : {
2056 : /* The size of the symbol table changed. */
2057 130 : shdr_info[cnt].shdr.sh_size = newdata->d_size
2058 65 : = destidx * elsize;
2059 65 : any_symtab_changes = true;
2060 : }
2061 : else
2062 : {
2063 : /* The symbol table didn't really change. */
2064 47 : free (shdr_info[cnt].newsymidx);
2065 47 : shdr_info[cnt].newsymidx = NULL;
2066 : }
2067 : }
2068 : }
2069 :
2070 : /* If we have to, compute the offset of the section.
2071 : If allocate and unallocated sections are mixed, we only update
2072 : the allocated ones now. The unallocated ones come second. */
2073 67669 : if (! mixed_allocated_unallocated
2074 66461 : || (shdr_info[cnt].shdr.sh_flags & SHF_ALLOC) != 0)
2075 : {
2076 1731 : if (shdr_info[cnt].shdr.sh_offset == 0)
2077 536 : shdr_info[cnt].shdr.sh_offset
2078 1072 : = ((lastoffset + shdr_info[cnt].shdr.sh_addralign - 1)
2079 536 : & ~((GElf_Off) (shdr_info[cnt].shdr.sh_addralign - 1)));
2080 :
2081 : /* Set the section header in the new file. */
2082 1731 : if (unlikely (gelf_update_shdr (scn, &shdr_info[cnt].shdr) == 0))
2083 : /* There cannot be any overflows. */
2084 0 : INTERNAL_ERROR (fname);
2085 :
2086 : /* Remember the last section written so far. */
2087 3462 : GElf_Off filesz = (shdr_info[cnt].shdr.sh_type != SHT_NOBITS
2088 1731 : ? shdr_info[cnt].shdr.sh_size : 0);
2089 1731 : if (lastoffset < shdr_info[cnt].shdr.sh_offset + filesz)
2090 1603 : lastoffset = shdr_info[cnt].shdr.sh_offset + filesz;
2091 : }
2092 : }
2093 :
2094 : /* We might have to update the unallocated sections after we done the
2095 : allocated ones. lastoffset is set to right after the last allocated
2096 : section. */
2097 96 : if (mixed_allocated_unallocated)
2098 198162 : for (cnt = 1; cnt <= shdridx; ++cnt)
2099 198115 : if (shdr_info[cnt].idx > 0)
2100 : {
2101 66461 : scn = elf_getscn (newelf, shdr_info[cnt].idx);
2102 66461 : if ((shdr_info[cnt].shdr.sh_flags & SHF_ALLOC) == 0)
2103 : {
2104 65938 : if (shdr_info[cnt].shdr.sh_offset == 0)
2105 65938 : shdr_info[cnt].shdr.sh_offset
2106 131876 : = ((lastoffset + shdr_info[cnt].shdr.sh_addralign - 1)
2107 65938 : & ~((GElf_Off) (shdr_info[cnt].shdr.sh_addralign - 1)));
2108 :
2109 : /* Set the section header in the new file. */
2110 65938 : if (unlikely (gelf_update_shdr (scn, &shdr_info[cnt].shdr) == 0))
2111 : /* There cannot be any overflows. */
2112 0 : INTERNAL_ERROR (fname);
2113 :
2114 : /* Remember the last section written so far. */
2115 131876 : GElf_Off filesz = (shdr_info[cnt].shdr.sh_type != SHT_NOBITS
2116 65938 : ? shdr_info[cnt].shdr.sh_size : 0);
2117 65938 : if (lastoffset < shdr_info[cnt].shdr.sh_offset + filesz)
2118 65934 : lastoffset = shdr_info[cnt].shdr.sh_offset + filesz;
2119 : }
2120 : }
2121 :
2122 : /* Adjust symbol references if symbol tables changed. */
2123 96 : if (any_symtab_changes)
2124 : /* Find all relocation sections which use this symbol table. */
2125 67653 : for (cnt = 1; cnt <= shdridx; ++cnt)
2126 : {
2127 : /* Update section headers when the data size has changed.
2128 : We also update the SHT_NOBITS section in the debug
2129 : file so that the section headers match in sh_size. */
2130 67590 : inline void update_section_size (const Elf_Data *newdata)
2131 : {
2132 0 : GElf_Shdr shdr_mem;
2133 0 : GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
2134 0 : shdr->sh_size = newdata->d_size;
2135 0 : (void) gelf_update_shdr (scn, shdr);
2136 0 : if (debugelf != NULL)
2137 : {
2138 : /* libelf will use d_size to set sh_size. */
2139 0 : Elf_Data *debugdata = elf_getdata (elf_getscn (debugelf,
2140 : cnt), NULL);
2141 0 : if (debugdata == NULL)
2142 0 : INTERNAL_ERROR (fname);
2143 0 : debugdata->d_size = newdata->d_size;
2144 : }
2145 0 : }
2146 :
2147 67590 : if (shdr_info[cnt].idx == 0 && debug_fname == NULL)
2148 : /* Ignore sections which are discarded. When we are saving a
2149 : relocation section in a separate debug file, we must fix up
2150 : the symbol table references. */
2151 : continue;
2152 :
2153 67379 : const Elf32_Word symtabidx = shdr_info[cnt].old_sh_link;
2154 67379 : elf_assert (symtabidx < shnum + 2);
2155 67379 : const Elf32_Word *const newsymidx = shdr_info[symtabidx].newsymidx;
2156 67379 : switch (shdr_info[cnt].shdr.sh_type)
2157 : {
2158 373 : inline bool no_symtab_updates (void)
2159 : {
2160 : /* If the symbol table hasn't changed, do not do anything. */
2161 417 : if (shdr_info[symtabidx].newsymidx == NULL)
2162 : return true;
2163 :
2164 : /* If the symbol table is not discarded, but additionally
2165 : duplicated in the separate debug file and this section
2166 : is discarded, don't adjust anything. */
2167 368 : return (shdr_info[cnt].idx == 0
2168 368 : && shdr_info[symtabidx].debug_data != NULL);
2169 : }
2170 :
2171 : case SHT_REL:
2172 : case SHT_RELA:
2173 719 : if (no_symtab_updates ())
2174 : break;
2175 :
2176 362 : Elf_Data *d = elf_getdata (shdr_info[cnt].idx == 0
2177 0 : ? elf_getscn (debugelf, cnt)
2178 181 : : elf_getscn (newelf,
2179 : shdr_info[cnt].idx),
2180 : NULL);
2181 181 : elf_assert (d != NULL && d->d_buf != NULL
2182 : && shdr_info[cnt].shdr.sh_entsize != 0);
2183 181 : size_t nrels = (shdr_info[cnt].shdr.sh_size
2184 : / shdr_info[cnt].shdr.sh_entsize);
2185 :
2186 181 : size_t symsize = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
2187 362 : const Elf32_Word symidxn = (shdr_info[symtabidx].data->d_size
2188 181 : / symsize);
2189 181 : if (shdr_info[cnt].shdr.sh_type == SHT_REL)
2190 2439 : for (size_t relidx = 0; relidx < nrels; ++relidx)
2191 : {
2192 2411 : GElf_Rel rel_mem;
2193 2411 : if (gelf_getrel (d, relidx, &rel_mem) == NULL)
2194 0 : INTERNAL_ERROR (fname);
2195 :
2196 2411 : size_t symidx = GELF_R_SYM (rel_mem.r_info);
2197 2411 : elf_assert (symidx < symidxn);
2198 2411 : if (newsymidx[symidx] != symidx)
2199 : {
2200 2206 : rel_mem.r_info
2201 2206 : = GELF_R_INFO (newsymidx[symidx],
2202 : GELF_R_TYPE (rel_mem.r_info));
2203 :
2204 2206 : if (gelf_update_rel (d, relidx, &rel_mem) == 0)
2205 0 : INTERNAL_ERROR (fname);
2206 : }
2207 : }
2208 : else
2209 12626 : for (size_t relidx = 0; relidx < nrels; ++relidx)
2210 : {
2211 12473 : GElf_Rela rel_mem;
2212 12473 : if (gelf_getrela (d, relidx, &rel_mem) == NULL)
2213 0 : INTERNAL_ERROR (fname);
2214 :
2215 12473 : size_t symidx = GELF_R_SYM (rel_mem.r_info);
2216 12473 : elf_assert (symidx < symidxn);
2217 12473 : if (newsymidx[symidx] != symidx)
2218 : {
2219 4139 : rel_mem.r_info
2220 4139 : = GELF_R_INFO (newsymidx[symidx],
2221 : GELF_R_TYPE (rel_mem.r_info));
2222 :
2223 4139 : if (gelf_update_rela (d, relidx, &rel_mem) == 0)
2224 0 : INTERNAL_ERROR (fname);
2225 : }
2226 : }
2227 : break;
2228 :
2229 : case SHT_HASH:
2230 19 : if (no_symtab_updates ())
2231 : break;
2232 :
2233 : /* We have to recompute the hash table. */
2234 :
2235 6 : elf_assert (shdr_info[cnt].idx > 0);
2236 :
2237 : /* The hash section in the new file. */
2238 6 : scn = elf_getscn (newelf, shdr_info[cnt].idx);
2239 :
2240 : /* The symbol table data. */
2241 6 : Elf_Data *symd = elf_getdata (elf_getscn (newelf,
2242 6 : shdr_info[symtabidx].idx),
2243 : NULL);
2244 6 : elf_assert (symd != NULL && symd->d_buf != NULL);
2245 :
2246 : /* The hash table data. */
2247 6 : Elf_Data *hashd = elf_getdata (scn, NULL);
2248 6 : elf_assert (hashd != NULL && hashd->d_buf != NULL);
2249 :
2250 6 : if (shdr_info[cnt].shdr.sh_entsize == sizeof (Elf32_Word))
2251 : {
2252 : /* Sane arches first. */
2253 6 : elf_assert (hashd->d_size >= 2 * sizeof (Elf32_Word));
2254 6 : Elf32_Word *bucket = (Elf32_Word *) hashd->d_buf;
2255 :
2256 6 : size_t strshndx = shdr_info[symtabidx].old_sh_link;
2257 6 : size_t elsize = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
2258 :
2259 6 : Elf32_Word nchain = bucket[1];
2260 6 : Elf32_Word nbucket = bucket[0];
2261 12 : uint64_t used_buf = ((2ULL + nchain + nbucket)
2262 6 : * sizeof (Elf32_Word));
2263 6 : elf_assert (used_buf <= hashd->d_size);
2264 :
2265 : /* Adjust the nchain value. The symbol table size
2266 : changed. We keep the same size for the bucket array. */
2267 6 : bucket[1] = symd->d_size / elsize;
2268 6 : bucket += 2;
2269 6 : Elf32_Word *chain = bucket + nbucket;
2270 :
2271 : /* New size of the section. */
2272 12 : size_t n_size = ((2 + symd->d_size / elsize + nbucket)
2273 6 : * sizeof (Elf32_Word));
2274 6 : elf_assert (n_size <= hashd->d_size);
2275 6 : hashd->d_size = n_size;
2276 6 : update_section_size (hashd);
2277 :
2278 : /* Clear the arrays. */
2279 18 : memset (bucket, '\0',
2280 6 : (symd->d_size / elsize + nbucket)
2281 : * sizeof (Elf32_Word));
2282 :
2283 6 : for (size_t inner = shdr_info[symtabidx].shdr.sh_info;
2284 78 : inner < symd->d_size / elsize; ++inner)
2285 : {
2286 72 : GElf_Sym sym_mem;
2287 72 : GElf_Sym *sym = gelf_getsym (symd, inner, &sym_mem);
2288 72 : elf_assert (sym != NULL);
2289 :
2290 216 : const char *name = elf_strptr (elf, strshndx,
2291 72 : sym->st_name);
2292 72 : elf_assert (name != NULL && nbucket != 0);
2293 72 : size_t hidx = elf_hash (name) % nbucket;
2294 :
2295 72 : if (bucket[hidx] == 0)
2296 60 : bucket[hidx] = inner;
2297 : else
2298 : {
2299 12 : hidx = bucket[hidx];
2300 :
2301 12 : while (chain[hidx] != 0 && chain[hidx] < nchain)
2302 0 : hidx = chain[hidx];
2303 :
2304 12 : chain[hidx] = inner;
2305 : }
2306 : }
2307 : }
2308 : else
2309 0 : {
2310 : /* Alpha and S390 64-bit use 64-bit SHT_HASH entries. */
2311 0 : elf_assert (shdr_info[cnt].shdr.sh_entsize
2312 : == sizeof (Elf64_Xword));
2313 :
2314 0 : Elf64_Xword *bucket = (Elf64_Xword *) hashd->d_buf;
2315 :
2316 0 : size_t strshndx = shdr_info[symtabidx].old_sh_link;
2317 0 : size_t elsize = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
2318 :
2319 0 : elf_assert (symd->d_size >= 2 * sizeof (Elf64_Xword));
2320 0 : Elf64_Xword nbucket = bucket[0];
2321 0 : Elf64_Xword nchain = bucket[1];
2322 0 : uint64_t maxwords = hashd->d_size / sizeof (Elf64_Xword);
2323 0 : elf_assert (maxwords >= 2
2324 : && maxwords - 2 >= nbucket
2325 : && maxwords - 2 - nbucket >= nchain);
2326 :
2327 : /* Adjust the nchain value. The symbol table size
2328 : changed. We keep the same size for the bucket array. */
2329 0 : bucket[1] = symd->d_size / elsize;
2330 0 : bucket += 2;
2331 0 : Elf64_Xword *chain = bucket + nbucket;
2332 :
2333 : /* New size of the section. */
2334 0 : size_t n_size = ((2 + symd->d_size / elsize + nbucket)
2335 0 : * sizeof (Elf64_Xword));
2336 0 : elf_assert (n_size <= hashd->d_size);
2337 0 : hashd->d_size = n_size;
2338 0 : update_section_size (hashd);
2339 :
2340 : /* Clear the arrays. */
2341 0 : memset (bucket, '\0',
2342 0 : (symd->d_size / elsize + nbucket)
2343 : * sizeof (Elf64_Xword));
2344 :
2345 0 : for (size_t inner = shdr_info[symtabidx].shdr.sh_info;
2346 0 : inner < symd->d_size / elsize; ++inner)
2347 : {
2348 0 : GElf_Sym sym_mem;
2349 0 : GElf_Sym *sym = gelf_getsym (symd, inner, &sym_mem);
2350 0 : elf_assert (sym != NULL);
2351 :
2352 0 : const char *name = elf_strptr (elf, strshndx,
2353 0 : sym->st_name);
2354 0 : elf_assert (name != NULL && nbucket != 0);
2355 0 : size_t hidx = elf_hash (name) % nbucket;
2356 :
2357 0 : if (bucket[hidx] == 0)
2358 0 : bucket[hidx] = inner;
2359 : else
2360 : {
2361 : hidx = bucket[hidx];
2362 :
2363 0 : while (chain[hidx] != 0 && chain[hidx] < nchain)
2364 : hidx = chain[hidx];
2365 :
2366 0 : chain[hidx] = inner;
2367 : }
2368 : }
2369 : }
2370 : break;
2371 :
2372 : case SHT_GNU_versym:
2373 : /* If the symbol table changed we have to adjust the entries. */
2374 27 : if (no_symtab_updates ())
2375 : break;
2376 :
2377 6 : elf_assert (shdr_info[cnt].idx > 0);
2378 :
2379 : /* The symbol version section in the new file. */
2380 6 : scn = elf_getscn (newelf, shdr_info[cnt].idx);
2381 :
2382 : /* The symbol table data. */
2383 6 : symd = elf_getdata (elf_getscn (newelf, shdr_info[symtabidx].idx),
2384 : NULL);
2385 6 : elf_assert (symd != NULL && symd->d_buf != NULL);
2386 6 : size_t symz = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
2387 6 : const Elf32_Word syms = (shdr_info[symtabidx].data->d_size / symz);
2388 :
2389 : /* The version symbol data. */
2390 6 : Elf_Data *verd = elf_getdata (scn, NULL);
2391 6 : elf_assert (verd != NULL && verd->d_buf != NULL);
2392 :
2393 : /* The symbol version array. */
2394 6 : GElf_Half *verstab = (GElf_Half *) verd->d_buf;
2395 :
2396 : /* Walk through the list and */
2397 6 : size_t elsize = gelf_fsize (elf, verd->d_type, 1, EV_CURRENT);
2398 6 : Elf32_Word vers = verd->d_size / elsize;
2399 258 : for (size_t inner = 1; inner < vers && inner < syms; ++inner)
2400 252 : if (newsymidx[inner] != 0 && newsymidx[inner] < vers)
2401 : /* Overwriting the same array works since the
2402 : reordering can only move entries to lower indices
2403 : in the array. */
2404 204 : verstab[newsymidx[inner]] = verstab[inner];
2405 :
2406 : /* New size of the section. */
2407 6 : verd->d_size = gelf_fsize (newelf, verd->d_type,
2408 6 : symd->d_size
2409 6 : / gelf_fsize (elf, symd->d_type, 1,
2410 : EV_CURRENT),
2411 : EV_CURRENT);
2412 6 : update_section_size (verd);
2413 6 : break;
2414 :
2415 : case SHT_GROUP:
2416 20 : if (no_symtab_updates ())
2417 : break;
2418 :
2419 : /* Yes, the symbol table changed.
2420 : Update the section header of the section group. */
2421 9 : scn = elf_getscn (newelf, shdr_info[cnt].idx);
2422 9 : GElf_Shdr shdr_mem;
2423 9 : GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
2424 9 : elf_assert (shdr != NULL);
2425 :
2426 9 : size_t symsz = gelf_fsize (elf, ELF_T_SYM, 1, EV_CURRENT);
2427 18 : const Elf32_Word symn = (shdr_info[symtabidx].data->d_size
2428 9 : / symsz);
2429 9 : elf_assert (shdr->sh_info < symn);
2430 9 : shdr->sh_info = newsymidx[shdr->sh_info];
2431 :
2432 9 : (void) gelf_update_shdr (scn, shdr);
2433 9 : break;
2434 : }
2435 67590 : }
2436 :
2437 : /* Remove any relocations between debug sections in ET_REL
2438 : for the debug file when requested. These relocations are always
2439 : zero based between the unallocated sections. */
2440 96 : if (debug_fname != NULL && removing_sections
2441 60 : && reloc_debug && ehdr->e_type == ET_REL)
2442 14 : remove_debug_relocations (ebl, debugelf, ehdr, fname, shstrndx);
2443 :
2444 : /* Now that we have done all adjustments to the data,
2445 : we can actually write out the debug file. */
2446 96 : if (debug_fname != NULL && removing_sections)
2447 : {
2448 : /* Finally write the file. */
2449 60 : if (unlikely (elf_update (debugelf, ELF_C_WRITE) == -1))
2450 : {
2451 0 : error (0, 0, gettext ("while writing '%s': %s"),
2452 : tmp_debug_fname, elf_errmsg (-1));
2453 0 : result = 1;
2454 0 : goto fail_close;
2455 : }
2456 :
2457 : /* Create the real output file. First rename, then change the
2458 : mode. */
2459 60 : if (rename (tmp_debug_fname, debug_fname) != 0
2460 60 : || fchmod (debug_fd, mode) != 0)
2461 : {
2462 0 : error (0, errno, gettext ("while creating '%s'"), debug_fname);
2463 0 : result = 1;
2464 0 : goto fail_close;
2465 : }
2466 :
2467 : /* The temporary file does not exist anymore. */
2468 60 : free (tmp_debug_fname);
2469 60 : tmp_debug_fname = NULL;
2470 :
2471 60 : if (!remove_shdrs)
2472 : {
2473 60 : uint32_t debug_crc;
2474 60 : Elf_Data debug_crc_data =
2475 : {
2476 : .d_type = ELF_T_WORD,
2477 : .d_buf = &debug_crc,
2478 : .d_size = sizeof (debug_crc),
2479 : .d_version = EV_CURRENT
2480 : };
2481 :
2482 : /* Compute the checksum which we will add to the executable. */
2483 60 : if (crc32_file (debug_fd, &debug_crc) != 0)
2484 : {
2485 0 : error (0, errno, gettext ("\
2486 : while computing checksum for debug information"));
2487 0 : unlink (debug_fname);
2488 0 : result = 1;
2489 0 : goto fail_close;
2490 : }
2491 :
2492 : /* Store it in the debuglink section data. */
2493 60 : if (unlikely (gelf_xlatetof (newelf, &debuglink_crc_data,
2494 : &debug_crc_data, ehdr->e_ident[EI_DATA])
2495 : != &debuglink_crc_data))
2496 0 : INTERNAL_ERROR (fname);
2497 : }
2498 : }
2499 :
2500 96 : lastsec_offset = shdr_info[shdridx].shdr.sh_offset;
2501 96 : lastsec_size = shdr_info[shdridx].shdr.sh_size;
2502 :
2503 111 : done:
2504 : /* Finally finish the ELF header. Fill in the fields not handled by
2505 : libelf from the old file. */
2506 111 : newehdr = gelf_getehdr (newelf, &newehdr_mem);
2507 111 : if (newehdr == NULL)
2508 0 : INTERNAL_ERROR (fname);
2509 :
2510 111 : memcpy (newehdr->e_ident, ehdr->e_ident, EI_NIDENT);
2511 111 : newehdr->e_type = ehdr->e_type;
2512 111 : newehdr->e_machine = ehdr->e_machine;
2513 111 : newehdr->e_version = ehdr->e_version;
2514 111 : newehdr->e_entry = ehdr->e_entry;
2515 111 : newehdr->e_flags = ehdr->e_flags;
2516 111 : newehdr->e_phoff = ehdr->e_phoff;
2517 :
2518 : /* We need to position the section header table. */
2519 111 : const size_t offsize = gelf_fsize (elf, ELF_T_OFF, 1, EV_CURRENT);
2520 222 : newehdr->e_shoff = ((lastsec_offset + lastsec_size + offsize - 1)
2521 111 : & ~((GElf_Off) (offsize - 1)));
2522 111 : newehdr->e_shentsize = gelf_fsize (elf, ELF_T_SHDR, 1, EV_CURRENT);
2523 :
2524 111 : if (gelf_update_ehdr (newelf, newehdr) == 0)
2525 : {
2526 0 : error (0, 0, gettext ("%s: error while creating ELF header: %s"),
2527 0 : output_fname ?: fname, elf_errmsg (-1));
2528 0 : cleanup_debug ();
2529 0 : return 1;
2530 : }
2531 :
2532 : /* The new section header string table index. */
2533 111 : if (update_shdrstrndx (newelf, idx) != 0)
2534 : {
2535 0 : error (0, 0, gettext ("%s: error updating shdrstrndx: %s"),
2536 0 : output_fname ?: fname, elf_errmsg (-1));
2537 0 : cleanup_debug ();
2538 0 : return 1;
2539 : }
2540 :
2541 : /* We have everything from the old file. */
2542 111 : if (elf_cntl (elf, ELF_C_FDDONE) != 0)
2543 : {
2544 0 : error (0, 0, gettext ("%s: error while reading the file: %s"),
2545 : fname, elf_errmsg (-1));
2546 0 : cleanup_debug ();
2547 0 : return 1;
2548 : }
2549 :
2550 : /* The ELF library better follows our layout when this is not a
2551 : relocatable object file. */
2552 222 : elf_flagelf (newelf, ELF_C_SET,
2553 111 : (phnum > 0 ? ELF_F_LAYOUT : 0)
2554 222 : | (permissive ? ELF_F_PERMISSIVE : 0));
2555 :
2556 : /* Finally write the file. */
2557 111 : if (elf_update (newelf, ELF_C_WRITE) == -1)
2558 : {
2559 0 : error (0, 0, gettext ("while writing '%s': %s"),
2560 0 : output_fname ?: fname, elf_errmsg (-1));
2561 0 : result = 1;
2562 : }
2563 :
2564 111 : if (remove_shdrs)
2565 : {
2566 : /* libelf can't cope without the section headers being properly intact.
2567 : So we just let it write them normally, and then we nuke them later. */
2568 :
2569 0 : if (newehdr->e_ident[EI_CLASS] == ELFCLASS32)
2570 : {
2571 0 : assert (offsetof (Elf32_Ehdr, e_shentsize) + sizeof (Elf32_Half)
2572 : == offsetof (Elf32_Ehdr, e_shnum));
2573 0 : assert (offsetof (Elf32_Ehdr, e_shnum) + sizeof (Elf32_Half)
2574 : == offsetof (Elf32_Ehdr, e_shstrndx));
2575 0 : const Elf32_Off zero_off = 0;
2576 0 : const Elf32_Half zero[3] = { 0, 0, SHN_UNDEF };
2577 0 : if (pwrite_retry (fd, &zero_off, sizeof zero_off,
2578 : offsetof (Elf32_Ehdr, e_shoff)) != sizeof zero_off
2579 0 : || (pwrite_retry (fd, zero, sizeof zero,
2580 : offsetof (Elf32_Ehdr, e_shentsize))
2581 : != sizeof zero)
2582 0 : || ftruncate (fd, lastsec_offset) < 0)
2583 : {
2584 0 : error (0, errno, gettext ("while writing '%s'"),
2585 0 : output_fname ?: fname);
2586 0 : result = 1;
2587 : }
2588 : }
2589 : else
2590 : {
2591 0 : assert (offsetof (Elf64_Ehdr, e_shentsize) + sizeof (Elf64_Half)
2592 : == offsetof (Elf64_Ehdr, e_shnum));
2593 0 : assert (offsetof (Elf64_Ehdr, e_shnum) + sizeof (Elf64_Half)
2594 : == offsetof (Elf64_Ehdr, e_shstrndx));
2595 0 : const Elf64_Off zero_off = 0;
2596 0 : const Elf64_Half zero[3] = { 0, 0, SHN_UNDEF };
2597 0 : if (pwrite_retry (fd, &zero_off, sizeof zero_off,
2598 : offsetof (Elf64_Ehdr, e_shoff)) != sizeof zero_off
2599 0 : || (pwrite_retry (fd, zero, sizeof zero,
2600 : offsetof (Elf64_Ehdr, e_shentsize))
2601 : != sizeof zero)
2602 0 : || ftruncate (fd, lastsec_offset) < 0)
2603 : {
2604 0 : error (0, errno, gettext ("while writing '%s'"),
2605 0 : output_fname ?: fname);
2606 0 : result = 1;
2607 : }
2608 : }
2609 : }
2610 :
2611 111 : fail_close:
2612 113 : if (shdr_info != NULL)
2613 : {
2614 : /* For some sections we might have created an table to map symbol
2615 : table indices. Or we might kept (original) data around to put
2616 : into the .debug file. */
2617 199852 : for (cnt = 1; cnt <= shdridx; ++cnt)
2618 : {
2619 199754 : free (shdr_info[cnt].newsymidx);
2620 199754 : if (shdr_info[cnt].debug_data != NULL)
2621 84 : free (shdr_info[cnt].debug_data->d_buf);
2622 : }
2623 :
2624 : /* Free data we allocated for the .gnu_debuglink section. */
2625 98 : free (debuglink_buf);
2626 :
2627 : /* Free the memory. */
2628 98 : if ((shnum + 2) * sizeof (struct shdr_info) > MAX_STACK_ALLOC)
2629 3 : free (shdr_info);
2630 : }
2631 :
2632 : /* Free other resources. */
2633 113 : if (shstrtab_data != NULL)
2634 96 : free (shstrtab_data->d_buf);
2635 113 : if (shst != NULL)
2636 98 : dwelf_strtab_free (shst);
2637 :
2638 : /* That was it. Close the descriptors. */
2639 113 : if (elf_end (newelf) != 0)
2640 : {
2641 0 : error (0, 0, gettext ("error while finishing '%s': %s"),
2642 0 : output_fname ?: fname, elf_errmsg (-1));
2643 0 : result = 1;
2644 : }
2645 :
2646 113 : if (debugelf != NULL && elf_end (debugelf) != 0)
2647 : {
2648 0 : error (0, 0, gettext ("error while finishing '%s': %s"), debug_fname,
2649 : elf_errmsg (-1));
2650 0 : result = 1;
2651 : }
2652 :
2653 113 : fail:
2654 : /* Close the EBL backend. */
2655 113 : if (ebl != NULL)
2656 56 : ebl_closebackend (ebl);
2657 :
2658 113 : cleanup_debug ();
2659 :
2660 : /* If requested, preserve the timestamp. */
2661 113 : if (tvp != NULL)
2662 : {
2663 0 : if (futimens (fd, tvp) != 0)
2664 : {
2665 0 : error (0, errno, gettext ("\
2666 : cannot set access and modification date of '%s'"),
2667 0 : output_fname ?: fname);
2668 0 : result = 1;
2669 : }
2670 : }
2671 :
2672 : /* Close the file descriptor if we created a new file. */
2673 113 : if (output_fname != NULL)
2674 : {
2675 81 : close (fd);
2676 81 : if (result != 0)
2677 0 : unlink (output_fname);
2678 : }
2679 :
2680 : return result;
2681 : }
2682 :
2683 : static void
2684 113 : cleanup_debug (void)
2685 : {
2686 113 : if (debug_fd >= 0)
2687 : {
2688 62 : if (tmp_debug_fname != NULL)
2689 : {
2690 2 : unlink (tmp_debug_fname);
2691 2 : free (tmp_debug_fname);
2692 2 : tmp_debug_fname = NULL;
2693 : }
2694 62 : close (debug_fd);
2695 62 : debug_fd = -1;
2696 : }
2697 113 : }
2698 :
2699 : static int
2700 : handle_ar (int fd, Elf *elf, const char *prefix, const char *fname,
2701 : struct timespec tvp[2])
2702 : {
2703 : size_t prefix_len = prefix == NULL ? 0 : strlen (prefix);
2704 : size_t fname_len = strlen (fname) + 1;
2705 : char new_prefix[prefix_len + 1 + fname_len];
2706 : char *cp = new_prefix;
2707 :
2708 : /* Create the full name of the file. */
2709 : if (prefix != NULL)
2710 : {
2711 : cp = mempcpy (cp, prefix, prefix_len);
2712 : *cp++ = ':';
2713 : }
2714 : memcpy (cp, fname, fname_len);
2715 :
2716 :
2717 : /* Process all the files contained in the archive. */
2718 : Elf *subelf;
2719 : Elf_Cmd cmd = ELF_C_RDWR;
2720 : int result = 0;
2721 : while ((subelf = elf_begin (fd, cmd, elf)) != NULL)
2722 : {
2723 : /* The the header for this element. */
2724 : Elf_Arhdr *arhdr = elf_getarhdr (subelf);
2725 :
2726 : if (elf_kind (subelf) == ELF_K_ELF)
2727 : result |= handle_elf (fd, subelf, new_prefix, arhdr->ar_name, 0, NULL);
2728 : else if (elf_kind (subelf) == ELF_K_AR)
2729 : result |= handle_ar (fd, subelf, new_prefix, arhdr->ar_name, NULL);
2730 :
2731 : /* Get next archive element. */
2732 : cmd = elf_next (subelf);
2733 : if (unlikely (elf_end (subelf) != 0))
2734 : INTERNAL_ERROR (fname);
2735 : }
2736 :
2737 : if (tvp != NULL)
2738 : {
2739 : if (unlikely (futimens (fd, tvp) != 0))
2740 : {
2741 : error (0, errno, gettext ("\
2742 : cannot set access and modification date of '%s'"), fname);
2743 : result = 1;
2744 : }
2745 : }
2746 :
2747 : if (unlikely (close (fd) != 0))
2748 : error (EXIT_FAILURE, errno, gettext ("while closing '%s'"), fname);
2749 :
2750 : return result;
2751 : }
2752 :
2753 :
2754 : #include "debugpred.h"
|
