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1// SPDX-License-Identifier: GPL-2.0
2/* This is included from relocs_32/64.c */
3
4#define ElfW(type) _ElfW(ELF_BITS, type)
5#define _ElfW(bits, type) __ElfW(bits, type)
6#define __ElfW(bits, type) Elf##bits##_##type
7
8#define Elf_Addr ElfW(Addr)
9#define Elf_Ehdr ElfW(Ehdr)
10#define Elf_Phdr ElfW(Phdr)
11#define Elf_Shdr ElfW(Shdr)
12#define Elf_Sym ElfW(Sym)
13
14static Elf_Ehdr ehdr;
15static unsigned long shnum;
16static unsigned int shstrndx;
17static unsigned int shsymtabndx;
18static unsigned int shxsymtabndx;
19
20static int sym_index(Elf_Sym *sym);
21
22struct relocs {
23 uint32_t *offset;
24 unsigned long count;
25 unsigned long size;
26};
27
28static struct relocs relocs16;
29static struct relocs relocs32;
30#if ELF_BITS == 64
31static struct relocs relocs32neg;
32static struct relocs relocs64;
33#define FMT PRIu64
34#else
35#define FMT PRIu32
36#endif
37
38struct section {
39 Elf_Shdr shdr;
40 struct section *link;
41 Elf_Sym *symtab;
42 Elf32_Word *xsymtab;
43 Elf_Rel *reltab;
44 char *strtab;
45};
46static struct section *secs;
47
48static const char * const sym_regex_kernel[S_NSYMTYPES] = {
49/*
50 * Following symbols have been audited. There values are constant and do
51 * not change if bzImage is loaded at a different physical address than
52 * the address for which it has been compiled. Don't warn user about
53 * absolute relocations present w.r.t these symbols.
54 */
55 [S_ABS] =
56 "^(xen_irq_disable_direct_reloc$|"
57 "xen_save_fl_direct_reloc$|"
58 "VDSO|"
59 "__kcfi_typeid_|"
60 "__crc_)",
61
62/*
63 * These symbols are known to be relative, even if the linker marks them
64 * as absolute (typically defined outside any section in the linker script.)
65 */
66 [S_REL] =
67 "^(__init_(begin|end)|"
68 "__x86_cpu_dev_(start|end)|"
69 "(__parainstructions|__alt_instructions)(_end)?|"
70 "(__iommu_table|__apicdrivers|__smp_locks)(_end)?|"
71 "__(start|end)_pci_.*|"
72#if CONFIG_FW_LOADER
73 "__(start|end)_builtin_fw|"
74#endif
75 "__(start|stop)___ksymtab(_gpl)?|"
76 "__(start|stop)___kcrctab(_gpl)?|"
77 "__(start|stop)___param|"
78 "__(start|stop)___modver|"
79 "__(start|stop)___bug_table|"
80 "__tracedata_(start|end)|"
81 "__(start|stop)_notes|"
82 "__end_rodata|"
83 "__end_rodata_aligned|"
84 "__initramfs_start|"
85 "(jiffies|jiffies_64)|"
86#if ELF_BITS == 64
87 "__per_cpu_load|"
88 "init_per_cpu__.*|"
89 "__end_rodata_hpage_align|"
90#endif
91 "__vvar_page|"
92 "_end)$"
93};
94
95
96static const char * const sym_regex_realmode[S_NSYMTYPES] = {
97/*
98 * These symbols are known to be relative, even if the linker marks them
99 * as absolute (typically defined outside any section in the linker script.)
100 */
101 [S_REL] =
102 "^pa_",
103
104/*
105 * These are 16-bit segment symbols when compiling 16-bit code.
106 */
107 [S_SEG] =
108 "^real_mode_seg$",
109
110/*
111 * These are offsets belonging to segments, as opposed to linear addresses,
112 * when compiling 16-bit code.
113 */
114 [S_LIN] =
115 "^pa_",
116};
117
118static const char * const *sym_regex;
119
120static regex_t sym_regex_c[S_NSYMTYPES];
121static int is_reloc(enum symtype type, const char *sym_name)
122{
123 return sym_regex[type] &&
124 !regexec(&sym_regex_c[type], sym_name, 0, NULL, 0);
125}
126
127static void regex_init(int use_real_mode)
128{
129 char errbuf[128];
130 int err;
131 int i;
132
133 if (use_real_mode)
134 sym_regex = sym_regex_realmode;
135 else
136 sym_regex = sym_regex_kernel;
137
138 for (i = 0; i < S_NSYMTYPES; i++) {
139 if (!sym_regex[i])
140 continue;
141
142 err = regcomp(&sym_regex_c[i], sym_regex[i],
143 REG_EXTENDED|REG_NOSUB);
144
145 if (err) {
146 regerror(err, &sym_regex_c[i], errbuf, sizeof(errbuf));
147 die("%s", errbuf);
148 }
149 }
150}
151
152static const char *sym_type(unsigned type)
153{
154 static const char *type_name[] = {
155#define SYM_TYPE(X) [X] = #X
156 SYM_TYPE(STT_NOTYPE),
157 SYM_TYPE(STT_OBJECT),
158 SYM_TYPE(STT_FUNC),
159 SYM_TYPE(STT_SECTION),
160 SYM_TYPE(STT_FILE),
161 SYM_TYPE(STT_COMMON),
162 SYM_TYPE(STT_TLS),
163#undef SYM_TYPE
164 };
165 const char *name = "unknown sym type name";
166 if (type < ARRAY_SIZE(type_name)) {
167 name = type_name[type];
168 }
169 return name;
170}
171
172static const char *sym_bind(unsigned bind)
173{
174 static const char *bind_name[] = {
175#define SYM_BIND(X) [X] = #X
176 SYM_BIND(STB_LOCAL),
177 SYM_BIND(STB_GLOBAL),
178 SYM_BIND(STB_WEAK),
179#undef SYM_BIND
180 };
181 const char *name = "unknown sym bind name";
182 if (bind < ARRAY_SIZE(bind_name)) {
183 name = bind_name[bind];
184 }
185 return name;
186}
187
188static const char *sym_visibility(unsigned visibility)
189{
190 static const char *visibility_name[] = {
191#define SYM_VISIBILITY(X) [X] = #X
192 SYM_VISIBILITY(STV_DEFAULT),
193 SYM_VISIBILITY(STV_INTERNAL),
194 SYM_VISIBILITY(STV_HIDDEN),
195 SYM_VISIBILITY(STV_PROTECTED),
196#undef SYM_VISIBILITY
197 };
198 const char *name = "unknown sym visibility name";
199 if (visibility < ARRAY_SIZE(visibility_name)) {
200 name = visibility_name[visibility];
201 }
202 return name;
203}
204
205static const char *rel_type(unsigned type)
206{
207 static const char *type_name[] = {
208#define REL_TYPE(X) [X] = #X
209#if ELF_BITS == 64
210 REL_TYPE(R_X86_64_NONE),
211 REL_TYPE(R_X86_64_64),
212 REL_TYPE(R_X86_64_PC64),
213 REL_TYPE(R_X86_64_PC32),
214 REL_TYPE(R_X86_64_GOT32),
215 REL_TYPE(R_X86_64_PLT32),
216 REL_TYPE(R_X86_64_COPY),
217 REL_TYPE(R_X86_64_GLOB_DAT),
218 REL_TYPE(R_X86_64_JUMP_SLOT),
219 REL_TYPE(R_X86_64_RELATIVE),
220 REL_TYPE(R_X86_64_GOTPCREL),
221 REL_TYPE(R_X86_64_32),
222 REL_TYPE(R_X86_64_32S),
223 REL_TYPE(R_X86_64_16),
224 REL_TYPE(R_X86_64_PC16),
225 REL_TYPE(R_X86_64_8),
226 REL_TYPE(R_X86_64_PC8),
227#else
228 REL_TYPE(R_386_NONE),
229 REL_TYPE(R_386_32),
230 REL_TYPE(R_386_PC32),
231 REL_TYPE(R_386_GOT32),
232 REL_TYPE(R_386_PLT32),
233 REL_TYPE(R_386_COPY),
234 REL_TYPE(R_386_GLOB_DAT),
235 REL_TYPE(R_386_JMP_SLOT),
236 REL_TYPE(R_386_RELATIVE),
237 REL_TYPE(R_386_GOTOFF),
238 REL_TYPE(R_386_GOTPC),
239 REL_TYPE(R_386_8),
240 REL_TYPE(R_386_PC8),
241 REL_TYPE(R_386_16),
242 REL_TYPE(R_386_PC16),
243#endif
244#undef REL_TYPE
245 };
246 const char *name = "unknown type rel type name";
247 if (type < ARRAY_SIZE(type_name) && type_name[type]) {
248 name = type_name[type];
249 }
250 return name;
251}
252
253static const char *sec_name(unsigned shndx)
254{
255 const char *sec_strtab;
256 const char *name;
257 sec_strtab = secs[shstrndx].strtab;
258 name = "<noname>";
259 if (shndx < shnum) {
260 name = sec_strtab + secs[shndx].shdr.sh_name;
261 }
262 else if (shndx == SHN_ABS) {
263 name = "ABSOLUTE";
264 }
265 else if (shndx == SHN_COMMON) {
266 name = "COMMON";
267 }
268 return name;
269}
270
271static const char *sym_name(const char *sym_strtab, Elf_Sym *sym)
272{
273 const char *name;
274 name = "<noname>";
275 if (sym->st_name) {
276 name = sym_strtab + sym->st_name;
277 }
278 else {
279 name = sec_name(sym_index(sym));
280 }
281 return name;
282}
283
284static Elf_Sym *sym_lookup(const char *symname)
285{
286 int i;
287 for (i = 0; i < shnum; i++) {
288 struct section *sec = &secs[i];
289 long nsyms;
290 char *strtab;
291 Elf_Sym *symtab;
292 Elf_Sym *sym;
293
294 if (sec->shdr.sh_type != SHT_SYMTAB)
295 continue;
296
297 nsyms = sec->shdr.sh_size/sizeof(Elf_Sym);
298 symtab = sec->symtab;
299 strtab = sec->link->strtab;
300
301 for (sym = symtab; --nsyms >= 0; sym++) {
302 if (!sym->st_name)
303 continue;
304 if (strcmp(symname, strtab + sym->st_name) == 0)
305 return sym;
306 }
307 }
308 return 0;
309}
310
311#if BYTE_ORDER == LITTLE_ENDIAN
312#define le16_to_cpu(val) (val)
313#define le32_to_cpu(val) (val)
314#define le64_to_cpu(val) (val)
315#endif
316#if BYTE_ORDER == BIG_ENDIAN
317#define le16_to_cpu(val) bswap_16(val)
318#define le32_to_cpu(val) bswap_32(val)
319#define le64_to_cpu(val) bswap_64(val)
320#endif
321
322static uint16_t elf16_to_cpu(uint16_t val)
323{
324 return le16_to_cpu(val);
325}
326
327static uint32_t elf32_to_cpu(uint32_t val)
328{
329 return le32_to_cpu(val);
330}
331
332#define elf_half_to_cpu(x) elf16_to_cpu(x)
333#define elf_word_to_cpu(x) elf32_to_cpu(x)
334
335#if ELF_BITS == 64
336static uint64_t elf64_to_cpu(uint64_t val)
337{
338 return le64_to_cpu(val);
339}
340#define elf_addr_to_cpu(x) elf64_to_cpu(x)
341#define elf_off_to_cpu(x) elf64_to_cpu(x)
342#define elf_xword_to_cpu(x) elf64_to_cpu(x)
343#else
344#define elf_addr_to_cpu(x) elf32_to_cpu(x)
345#define elf_off_to_cpu(x) elf32_to_cpu(x)
346#define elf_xword_to_cpu(x) elf32_to_cpu(x)
347#endif
348
349static int sym_index(Elf_Sym *sym)
350{
351 Elf_Sym *symtab = secs[shsymtabndx].symtab;
352 Elf32_Word *xsymtab = secs[shxsymtabndx].xsymtab;
353 unsigned long offset;
354 int index;
355
356 if (sym->st_shndx != SHN_XINDEX)
357 return sym->st_shndx;
358
359 /* calculate offset of sym from head of table. */
360 offset = (unsigned long)sym - (unsigned long)symtab;
361 index = offset / sizeof(*sym);
362
363 return elf32_to_cpu(xsymtab[index]);
364}
365
366static void read_ehdr(FILE *fp)
367{
368 if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1) {
369 die("Cannot read ELF header: %s\n",
370 strerror(errno));
371 }
372 if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0) {
373 die("No ELF magic\n");
374 }
375 if (ehdr.e_ident[EI_CLASS] != ELF_CLASS) {
376 die("Not a %d bit executable\n", ELF_BITS);
377 }
378 if (ehdr.e_ident[EI_DATA] != ELFDATA2LSB) {
379 die("Not a LSB ELF executable\n");
380 }
381 if (ehdr.e_ident[EI_VERSION] != EV_CURRENT) {
382 die("Unknown ELF version\n");
383 }
384 /* Convert the fields to native endian */
385 ehdr.e_type = elf_half_to_cpu(ehdr.e_type);
386 ehdr.e_machine = elf_half_to_cpu(ehdr.e_machine);
387 ehdr.e_version = elf_word_to_cpu(ehdr.e_version);
388 ehdr.e_entry = elf_addr_to_cpu(ehdr.e_entry);
389 ehdr.e_phoff = elf_off_to_cpu(ehdr.e_phoff);
390 ehdr.e_shoff = elf_off_to_cpu(ehdr.e_shoff);
391 ehdr.e_flags = elf_word_to_cpu(ehdr.e_flags);
392 ehdr.e_ehsize = elf_half_to_cpu(ehdr.e_ehsize);
393 ehdr.e_phentsize = elf_half_to_cpu(ehdr.e_phentsize);
394 ehdr.e_phnum = elf_half_to_cpu(ehdr.e_phnum);
395 ehdr.e_shentsize = elf_half_to_cpu(ehdr.e_shentsize);
396 ehdr.e_shnum = elf_half_to_cpu(ehdr.e_shnum);
397 ehdr.e_shstrndx = elf_half_to_cpu(ehdr.e_shstrndx);
398
399 shnum = ehdr.e_shnum;
400 shstrndx = ehdr.e_shstrndx;
401
402 if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN))
403 die("Unsupported ELF header type\n");
404 if (ehdr.e_machine != ELF_MACHINE)
405 die("Not for %s\n", ELF_MACHINE_NAME);
406 if (ehdr.e_version != EV_CURRENT)
407 die("Unknown ELF version\n");
408 if (ehdr.e_ehsize != sizeof(Elf_Ehdr))
409 die("Bad Elf header size\n");
410 if (ehdr.e_phentsize != sizeof(Elf_Phdr))
411 die("Bad program header entry\n");
412 if (ehdr.e_shentsize != sizeof(Elf_Shdr))
413 die("Bad section header entry\n");
414
415
416 if (shnum == SHN_UNDEF || shstrndx == SHN_XINDEX) {
417 Elf_Shdr shdr;
418
419 if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0)
420 die("Seek to %" FMT " failed: %s\n", ehdr.e_shoff, strerror(errno));
421
422 if (fread(&shdr, sizeof(shdr), 1, fp) != 1)
423 die("Cannot read initial ELF section header: %s\n", strerror(errno));
424
425 if (shnum == SHN_UNDEF)
426 shnum = elf_xword_to_cpu(shdr.sh_size);
427
428 if (shstrndx == SHN_XINDEX)
429 shstrndx = elf_word_to_cpu(shdr.sh_link);
430 }
431
432 if (shstrndx >= shnum)
433 die("String table index out of bounds\n");
434}
435
436static void read_shdrs(FILE *fp)
437{
438 int i;
439 Elf_Shdr shdr;
440
441 secs = calloc(shnum, sizeof(struct section));
442 if (!secs) {
443 die("Unable to allocate %ld section headers\n",
444 shnum);
445 }
446 if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
447 die("Seek to %" FMT " failed: %s\n",
448 ehdr.e_shoff, strerror(errno));
449 }
450 for (i = 0; i < shnum; i++) {
451 struct section *sec = &secs[i];
452 if (fread(&shdr, sizeof(shdr), 1, fp) != 1)
453 die("Cannot read ELF section headers %d/%ld: %s\n",
454 i, shnum, strerror(errno));
455 sec->shdr.sh_name = elf_word_to_cpu(shdr.sh_name);
456 sec->shdr.sh_type = elf_word_to_cpu(shdr.sh_type);
457 sec->shdr.sh_flags = elf_xword_to_cpu(shdr.sh_flags);
458 sec->shdr.sh_addr = elf_addr_to_cpu(shdr.sh_addr);
459 sec->shdr.sh_offset = elf_off_to_cpu(shdr.sh_offset);
460 sec->shdr.sh_size = elf_xword_to_cpu(shdr.sh_size);
461 sec->shdr.sh_link = elf_word_to_cpu(shdr.sh_link);
462 sec->shdr.sh_info = elf_word_to_cpu(shdr.sh_info);
463 sec->shdr.sh_addralign = elf_xword_to_cpu(shdr.sh_addralign);
464 sec->shdr.sh_entsize = elf_xword_to_cpu(shdr.sh_entsize);
465 if (sec->shdr.sh_link < shnum)
466 sec->link = &secs[sec->shdr.sh_link];
467 }
468
469}
470
471static void read_strtabs(FILE *fp)
472{
473 int i;
474 for (i = 0; i < shnum; i++) {
475 struct section *sec = &secs[i];
476 if (sec->shdr.sh_type != SHT_STRTAB) {
477 continue;
478 }
479 sec->strtab = malloc(sec->shdr.sh_size);
480 if (!sec->strtab) {
481 die("malloc of %" FMT " bytes for strtab failed\n",
482 sec->shdr.sh_size);
483 }
484 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
485 die("Seek to %" FMT " failed: %s\n",
486 sec->shdr.sh_offset, strerror(errno));
487 }
488 if (fread(sec->strtab, 1, sec->shdr.sh_size, fp)
489 != sec->shdr.sh_size) {
490 die("Cannot read symbol table: %s\n",
491 strerror(errno));
492 }
493 }
494}
495
496static void read_symtabs(FILE *fp)
497{
498 int i,j;
499
500 for (i = 0; i < shnum; i++) {
501 struct section *sec = &secs[i];
502 int num_syms;
503
504 switch (sec->shdr.sh_type) {
505 case SHT_SYMTAB_SHNDX:
506 sec->xsymtab = malloc(sec->shdr.sh_size);
507 if (!sec->xsymtab) {
508 die("malloc of %" FMT " bytes for xsymtab failed\n",
509 sec->shdr.sh_size);
510 }
511 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
512 die("Seek to %" FMT " failed: %s\n",
513 sec->shdr.sh_offset, strerror(errno));
514 }
515 if (fread(sec->xsymtab, 1, sec->shdr.sh_size, fp)
516 != sec->shdr.sh_size) {
517 die("Cannot read extended symbol table: %s\n",
518 strerror(errno));
519 }
520 shxsymtabndx = i;
521 continue;
522
523 case SHT_SYMTAB:
524 num_syms = sec->shdr.sh_size / sizeof(Elf_Sym);
525
526 sec->symtab = malloc(sec->shdr.sh_size);
527 if (!sec->symtab) {
528 die("malloc of %" FMT " bytes for symtab failed\n",
529 sec->shdr.sh_size);
530 }
531 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
532 die("Seek to %" FMT " failed: %s\n",
533 sec->shdr.sh_offset, strerror(errno));
534 }
535 if (fread(sec->symtab, 1, sec->shdr.sh_size, fp)
536 != sec->shdr.sh_size) {
537 die("Cannot read symbol table: %s\n",
538 strerror(errno));
539 }
540 for (j = 0; j < num_syms; j++) {
541 Elf_Sym *sym = &sec->symtab[j];
542
543 sym->st_name = elf_word_to_cpu(sym->st_name);
544 sym->st_value = elf_addr_to_cpu(sym->st_value);
545 sym->st_size = elf_xword_to_cpu(sym->st_size);
546 sym->st_shndx = elf_half_to_cpu(sym->st_shndx);
547 }
548 shsymtabndx = i;
549 continue;
550
551 default:
552 continue;
553 }
554 }
555}
556
557
558static void read_relocs(FILE *fp)
559{
560 int i,j;
561 for (i = 0; i < shnum; i++) {
562 struct section *sec = &secs[i];
563 if (sec->shdr.sh_type != SHT_REL_TYPE) {
564 continue;
565 }
566 sec->reltab = malloc(sec->shdr.sh_size);
567 if (!sec->reltab) {
568 die("malloc of %" FMT " bytes for relocs failed\n",
569 sec->shdr.sh_size);
570 }
571 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
572 die("Seek to %" FMT " failed: %s\n",
573 sec->shdr.sh_offset, strerror(errno));
574 }
575 if (fread(sec->reltab, 1, sec->shdr.sh_size, fp)
576 != sec->shdr.sh_size) {
577 die("Cannot read symbol table: %s\n",
578 strerror(errno));
579 }
580 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
581 Elf_Rel *rel = &sec->reltab[j];
582 rel->r_offset = elf_addr_to_cpu(rel->r_offset);
583 rel->r_info = elf_xword_to_cpu(rel->r_info);
584#if (SHT_REL_TYPE == SHT_RELA)
585 rel->r_addend = elf_xword_to_cpu(rel->r_addend);
586#endif
587 }
588 }
589}
590
591
592static void print_absolute_symbols(void)
593{
594 int i;
595 const char *format;
596
597 if (ELF_BITS == 64)
598 format = "%5d %016"PRIx64" %5"PRId64" %10s %10s %12s %s\n";
599 else
600 format = "%5d %08"PRIx32" %5"PRId32" %10s %10s %12s %s\n";
601
602 printf("Absolute symbols\n");
603 printf(" Num: Value Size Type Bind Visibility Name\n");
604 for (i = 0; i < shnum; i++) {
605 struct section *sec = &secs[i];
606 char *sym_strtab;
607 int j;
608
609 if (sec->shdr.sh_type != SHT_SYMTAB) {
610 continue;
611 }
612 sym_strtab = sec->link->strtab;
613 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Sym); j++) {
614 Elf_Sym *sym;
615 const char *name;
616 sym = &sec->symtab[j];
617 name = sym_name(sym_strtab, sym);
618 if (sym->st_shndx != SHN_ABS) {
619 continue;
620 }
621 printf(format,
622 j, sym->st_value, sym->st_size,
623 sym_type(ELF_ST_TYPE(sym->st_info)),
624 sym_bind(ELF_ST_BIND(sym->st_info)),
625 sym_visibility(ELF_ST_VISIBILITY(sym->st_other)),
626 name);
627 }
628 }
629 printf("\n");
630}
631
632static void print_absolute_relocs(void)
633{
634 int i, printed = 0;
635 const char *format;
636
637 if (ELF_BITS == 64)
638 format = "%016"PRIx64" %016"PRIx64" %10s %016"PRIx64" %s\n";
639 else
640 format = "%08"PRIx32" %08"PRIx32" %10s %08"PRIx32" %s\n";
641
642 for (i = 0; i < shnum; i++) {
643 struct section *sec = &secs[i];
644 struct section *sec_applies, *sec_symtab;
645 char *sym_strtab;
646 Elf_Sym *sh_symtab;
647 int j;
648 if (sec->shdr.sh_type != SHT_REL_TYPE) {
649 continue;
650 }
651 sec_symtab = sec->link;
652 sec_applies = &secs[sec->shdr.sh_info];
653 if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) {
654 continue;
655 }
656 sh_symtab = sec_symtab->symtab;
657 sym_strtab = sec_symtab->link->strtab;
658 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
659 Elf_Rel *rel;
660 Elf_Sym *sym;
661 const char *name;
662 rel = &sec->reltab[j];
663 sym = &sh_symtab[ELF_R_SYM(rel->r_info)];
664 name = sym_name(sym_strtab, sym);
665 if (sym->st_shndx != SHN_ABS) {
666 continue;
667 }
668
669 /* Absolute symbols are not relocated if bzImage is
670 * loaded at a non-compiled address. Display a warning
671 * to user at compile time about the absolute
672 * relocations present.
673 *
674 * User need to audit the code to make sure
675 * some symbols which should have been section
676 * relative have not become absolute because of some
677 * linker optimization or wrong programming usage.
678 *
679 * Before warning check if this absolute symbol
680 * relocation is harmless.
681 */
682 if (is_reloc(S_ABS, name) || is_reloc(S_REL, name))
683 continue;
684
685 if (!printed) {
686 printf("WARNING: Absolute relocations"
687 " present\n");
688 printf("Offset Info Type Sym.Value "
689 "Sym.Name\n");
690 printed = 1;
691 }
692
693 printf(format,
694 rel->r_offset,
695 rel->r_info,
696 rel_type(ELF_R_TYPE(rel->r_info)),
697 sym->st_value,
698 name);
699 }
700 }
701
702 if (printed)
703 printf("\n");
704}
705
706static void add_reloc(struct relocs *r, uint32_t offset)
707{
708 if (r->count == r->size) {
709 unsigned long newsize = r->size + 50000;
710 void *mem = realloc(r->offset, newsize * sizeof(r->offset[0]));
711
712 if (!mem)
713 die("realloc of %ld entries for relocs failed\n",
714 newsize);
715 r->offset = mem;
716 r->size = newsize;
717 }
718 r->offset[r->count++] = offset;
719}
720
721static void walk_relocs(int (*process)(struct section *sec, Elf_Rel *rel,
722 Elf_Sym *sym, const char *symname))
723{
724 int i;
725 /* Walk through the relocations */
726 for (i = 0; i < shnum; i++) {
727 char *sym_strtab;
728 Elf_Sym *sh_symtab;
729 struct section *sec_applies, *sec_symtab;
730 int j;
731 struct section *sec = &secs[i];
732
733 if (sec->shdr.sh_type != SHT_REL_TYPE) {
734 continue;
735 }
736 sec_symtab = sec->link;
737 sec_applies = &secs[sec->shdr.sh_info];
738 if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) {
739 continue;
740 }
741 sh_symtab = sec_symtab->symtab;
742 sym_strtab = sec_symtab->link->strtab;
743 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
744 Elf_Rel *rel = &sec->reltab[j];
745 Elf_Sym *sym = &sh_symtab[ELF_R_SYM(rel->r_info)];
746 const char *symname = sym_name(sym_strtab, sym);
747
748 process(sec, rel, sym, symname);
749 }
750 }
751}
752
753/*
754 * The .data..percpu section is a special case for x86_64 SMP kernels.
755 * It is used to initialize the actual per_cpu areas and to provide
756 * definitions for the per_cpu variables that correspond to their offsets
757 * within the percpu area. Since the values of all of the symbols need
758 * to be offsets from the start of the per_cpu area the virtual address
759 * (sh_addr) of .data..percpu is 0 in SMP kernels.
760 *
761 * This means that:
762 *
763 * Relocations that reference symbols in the per_cpu area do not
764 * need further relocation (since the value is an offset relative
765 * to the start of the per_cpu area that does not change).
766 *
767 * Relocations that apply to the per_cpu area need to have their
768 * offset adjusted by by the value of __per_cpu_load to make them
769 * point to the correct place in the loaded image (because the
770 * virtual address of .data..percpu is 0).
771 *
772 * For non SMP kernels .data..percpu is linked as part of the normal
773 * kernel data and does not require special treatment.
774 *
775 */
776static int per_cpu_shndx = -1;
777static Elf_Addr per_cpu_load_addr;
778
779static void percpu_init(void)
780{
781 int i;
782 for (i = 0; i < shnum; i++) {
783 ElfW(Sym) *sym;
784 if (strcmp(sec_name(i), ".data..percpu"))
785 continue;
786
787 if (secs[i].shdr.sh_addr != 0) /* non SMP kernel */
788 return;
789
790 sym = sym_lookup("__per_cpu_load");
791 if (!sym)
792 die("can't find __per_cpu_load\n");
793
794 per_cpu_shndx = i;
795 per_cpu_load_addr = sym->st_value;
796 return;
797 }
798}
799
800#if ELF_BITS == 64
801
802/*
803 * Check to see if a symbol lies in the .data..percpu section.
804 *
805 * The linker incorrectly associates some symbols with the
806 * .data..percpu section so we also need to check the symbol
807 * name to make sure that we classify the symbol correctly.
808 *
809 * The GNU linker incorrectly associates:
810 * __init_begin
811 * __per_cpu_load
812 *
813 * The "gold" linker incorrectly associates:
814 * init_per_cpu__fixed_percpu_data
815 * init_per_cpu__gdt_page
816 */
817static int is_percpu_sym(ElfW(Sym) *sym, const char *symname)
818{
819 int shndx = sym_index(sym);
820
821 return (shndx == per_cpu_shndx) &&
822 strcmp(symname, "__init_begin") &&
823 strcmp(symname, "__per_cpu_load") &&
824 strncmp(symname, "init_per_cpu_", 13);
825}
826
827
828static int do_reloc64(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym,
829 const char *symname)
830{
831 unsigned r_type = ELF64_R_TYPE(rel->r_info);
832 ElfW(Addr) offset = rel->r_offset;
833 int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
834
835 if (sym->st_shndx == SHN_UNDEF)
836 return 0;
837
838 /*
839 * Adjust the offset if this reloc applies to the percpu section.
840 */
841 if (sec->shdr.sh_info == per_cpu_shndx)
842 offset += per_cpu_load_addr;
843
844 switch (r_type) {
845 case R_X86_64_NONE:
846 /* NONE can be ignored. */
847 break;
848
849 case R_X86_64_PC32:
850 case R_X86_64_PLT32:
851 /*
852 * PC relative relocations don't need to be adjusted unless
853 * referencing a percpu symbol.
854 *
855 * NB: R_X86_64_PLT32 can be treated as R_X86_64_PC32.
856 */
857 if (is_percpu_sym(sym, symname))
858 add_reloc(&relocs32neg, offset);
859 break;
860
861 case R_X86_64_PC64:
862 /*
863 * Only used by jump labels
864 */
865 if (is_percpu_sym(sym, symname))
866 die("Invalid R_X86_64_PC64 relocation against per-CPU symbol %s\n",
867 symname);
868 break;
869
870 case R_X86_64_32:
871 case R_X86_64_32S:
872 case R_X86_64_64:
873 /*
874 * References to the percpu area don't need to be adjusted.
875 */
876 if (is_percpu_sym(sym, symname))
877 break;
878
879 if (shn_abs) {
880 /*
881 * Whitelisted absolute symbols do not require
882 * relocation.
883 */
884 if (is_reloc(S_ABS, symname))
885 break;
886
887 die("Invalid absolute %s relocation: %s\n",
888 rel_type(r_type), symname);
889 break;
890 }
891
892 /*
893 * Relocation offsets for 64 bit kernels are output
894 * as 32 bits and sign extended back to 64 bits when
895 * the relocations are processed.
896 * Make sure that the offset will fit.
897 */
898 if ((int32_t)offset != (int64_t)offset)
899 die("Relocation offset doesn't fit in 32 bits\n");
900
901 if (r_type == R_X86_64_64)
902 add_reloc(&relocs64, offset);
903 else
904 add_reloc(&relocs32, offset);
905 break;
906
907 default:
908 die("Unsupported relocation type: %s (%d)\n",
909 rel_type(r_type), r_type);
910 break;
911 }
912
913 return 0;
914}
915
916#else
917
918static int do_reloc32(struct section *sec, Elf_Rel *rel, Elf_Sym *sym,
919 const char *symname)
920{
921 unsigned r_type = ELF32_R_TYPE(rel->r_info);
922 int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
923
924 switch (r_type) {
925 case R_386_NONE:
926 case R_386_PC32:
927 case R_386_PC16:
928 case R_386_PC8:
929 case R_386_PLT32:
930 /*
931 * NONE can be ignored and PC relative relocations don't need
932 * to be adjusted. Because sym must be defined, R_386_PLT32 can
933 * be treated the same way as R_386_PC32.
934 */
935 break;
936
937 case R_386_32:
938 if (shn_abs) {
939 /*
940 * Whitelisted absolute symbols do not require
941 * relocation.
942 */
943 if (is_reloc(S_ABS, symname))
944 break;
945
946 die("Invalid absolute %s relocation: %s\n",
947 rel_type(r_type), symname);
948 break;
949 }
950
951 add_reloc(&relocs32, rel->r_offset);
952 break;
953
954 default:
955 die("Unsupported relocation type: %s (%d)\n",
956 rel_type(r_type), r_type);
957 break;
958 }
959
960 return 0;
961}
962
963static int do_reloc_real(struct section *sec, Elf_Rel *rel, Elf_Sym *sym,
964 const char *symname)
965{
966 unsigned r_type = ELF32_R_TYPE(rel->r_info);
967 int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
968
969 switch (r_type) {
970 case R_386_NONE:
971 case R_386_PC32:
972 case R_386_PC16:
973 case R_386_PC8:
974 case R_386_PLT32:
975 /*
976 * NONE can be ignored and PC relative relocations don't need
977 * to be adjusted. Because sym must be defined, R_386_PLT32 can
978 * be treated the same way as R_386_PC32.
979 */
980 break;
981
982 case R_386_16:
983 if (shn_abs) {
984 /*
985 * Whitelisted absolute symbols do not require
986 * relocation.
987 */
988 if (is_reloc(S_ABS, symname))
989 break;
990
991 if (is_reloc(S_SEG, symname)) {
992 add_reloc(&relocs16, rel->r_offset);
993 break;
994 }
995 } else {
996 if (!is_reloc(S_LIN, symname))
997 break;
998 }
999 die("Invalid %s %s relocation: %s\n",
1000 shn_abs ? "absolute" : "relative",
1001 rel_type(r_type), symname);
1002 break;
1003
1004 case R_386_32:
1005 if (shn_abs) {
1006 /*
1007 * Whitelisted absolute symbols do not require
1008 * relocation.
1009 */
1010 if (is_reloc(S_ABS, symname))
1011 break;
1012
1013 if (is_reloc(S_REL, symname)) {
1014 add_reloc(&relocs32, rel->r_offset);
1015 break;
1016 }
1017 } else {
1018 if (is_reloc(S_LIN, symname))
1019 add_reloc(&relocs32, rel->r_offset);
1020 break;
1021 }
1022 die("Invalid %s %s relocation: %s\n",
1023 shn_abs ? "absolute" : "relative",
1024 rel_type(r_type), symname);
1025 break;
1026
1027 default:
1028 die("Unsupported relocation type: %s (%d)\n",
1029 rel_type(r_type), r_type);
1030 break;
1031 }
1032
1033 return 0;
1034}
1035
1036#endif
1037
1038static int cmp_relocs(const void *va, const void *vb)
1039{
1040 const uint32_t *a, *b;
1041 a = va; b = vb;
1042 return (*a == *b)? 0 : (*a > *b)? 1 : -1;
1043}
1044
1045static void sort_relocs(struct relocs *r)
1046{
1047 qsort(r->offset, r->count, sizeof(r->offset[0]), cmp_relocs);
1048}
1049
1050static int write32(uint32_t v, FILE *f)
1051{
1052 unsigned char buf[4];
1053
1054 put_unaligned_le32(v, buf);
1055 return fwrite(buf, 1, 4, f) == 4 ? 0 : -1;
1056}
1057
1058static int write32_as_text(uint32_t v, FILE *f)
1059{
1060 return fprintf(f, "\t.long 0x%08"PRIx32"\n", v) > 0 ? 0 : -1;
1061}
1062
1063static void emit_relocs(int as_text, int use_real_mode)
1064{
1065 int i;
1066 int (*write_reloc)(uint32_t, FILE *) = write32;
1067 int (*do_reloc)(struct section *sec, Elf_Rel *rel, Elf_Sym *sym,
1068 const char *symname);
1069
1070#if ELF_BITS == 64
1071 if (!use_real_mode)
1072 do_reloc = do_reloc64;
1073 else
1074 die("--realmode not valid for a 64-bit ELF file");
1075#else
1076 if (!use_real_mode)
1077 do_reloc = do_reloc32;
1078 else
1079 do_reloc = do_reloc_real;
1080#endif
1081
1082 /* Collect up the relocations */
1083 walk_relocs(do_reloc);
1084
1085 if (relocs16.count && !use_real_mode)
1086 die("Segment relocations found but --realmode not specified\n");
1087
1088 /* Order the relocations for more efficient processing */
1089 sort_relocs(&relocs32);
1090#if ELF_BITS == 64
1091 sort_relocs(&relocs32neg);
1092 sort_relocs(&relocs64);
1093#else
1094 sort_relocs(&relocs16);
1095#endif
1096
1097 /* Print the relocations */
1098 if (as_text) {
1099 /* Print the relocations in a form suitable that
1100 * gas will like.
1101 */
1102 printf(".section \".data.reloc\",\"a\"\n");
1103 printf(".balign 4\n");
1104 write_reloc = write32_as_text;
1105 }
1106
1107 if (use_real_mode) {
1108 write_reloc(relocs16.count, stdout);
1109 for (i = 0; i < relocs16.count; i++)
1110 write_reloc(relocs16.offset[i], stdout);
1111
1112 write_reloc(relocs32.count, stdout);
1113 for (i = 0; i < relocs32.count; i++)
1114 write_reloc(relocs32.offset[i], stdout);
1115 } else {
1116#if ELF_BITS == 64
1117 /* Print a stop */
1118 write_reloc(0, stdout);
1119
1120 /* Now print each relocation */
1121 for (i = 0; i < relocs64.count; i++)
1122 write_reloc(relocs64.offset[i], stdout);
1123
1124 /* Print a stop */
1125 write_reloc(0, stdout);
1126
1127 /* Now print each inverse 32-bit relocation */
1128 for (i = 0; i < relocs32neg.count; i++)
1129 write_reloc(relocs32neg.offset[i], stdout);
1130#endif
1131
1132 /* Print a stop */
1133 write_reloc(0, stdout);
1134
1135 /* Now print each relocation */
1136 for (i = 0; i < relocs32.count; i++)
1137 write_reloc(relocs32.offset[i], stdout);
1138 }
1139}
1140
1141/*
1142 * As an aid to debugging problems with different linkers
1143 * print summary information about the relocs.
1144 * Since different linkers tend to emit the sections in
1145 * different orders we use the section names in the output.
1146 */
1147static int do_reloc_info(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym,
1148 const char *symname)
1149{
1150 printf("%s\t%s\t%s\t%s\n",
1151 sec_name(sec->shdr.sh_info),
1152 rel_type(ELF_R_TYPE(rel->r_info)),
1153 symname,
1154 sec_name(sym_index(sym)));
1155 return 0;
1156}
1157
1158static void print_reloc_info(void)
1159{
1160 printf("reloc section\treloc type\tsymbol\tsymbol section\n");
1161 walk_relocs(do_reloc_info);
1162}
1163
1164#if ELF_BITS == 64
1165# define process process_64
1166#else
1167# define process process_32
1168#endif
1169
1170void process(FILE *fp, int use_real_mode, int as_text,
1171 int show_absolute_syms, int show_absolute_relocs,
1172 int show_reloc_info)
1173{
1174 regex_init(use_real_mode);
1175 read_ehdr(fp);
1176 read_shdrs(fp);
1177 read_strtabs(fp);
1178 read_symtabs(fp);
1179 read_relocs(fp);
1180 if (ELF_BITS == 64)
1181 percpu_init();
1182 if (show_absolute_syms) {
1183 print_absolute_symbols();
1184 return;
1185 }
1186 if (show_absolute_relocs) {
1187 print_absolute_relocs();
1188 return;
1189 }
1190 if (show_reloc_info) {
1191 print_reloc_info();
1192 return;
1193 }
1194 emit_relocs(as_text, use_real_mode);
1195}
1/* This is included from relocs_32/64.c */
2
3#define ElfW(type) _ElfW(ELF_BITS, type)
4#define _ElfW(bits, type) __ElfW(bits, type)
5#define __ElfW(bits, type) Elf##bits##_##type
6
7#define Elf_Addr ElfW(Addr)
8#define Elf_Ehdr ElfW(Ehdr)
9#define Elf_Phdr ElfW(Phdr)
10#define Elf_Shdr ElfW(Shdr)
11#define Elf_Sym ElfW(Sym)
12
13static Elf_Ehdr ehdr;
14
15struct relocs {
16 uint32_t *offset;
17 unsigned long count;
18 unsigned long size;
19};
20
21static struct relocs relocs16;
22static struct relocs relocs32;
23static struct relocs relocs64;
24
25struct section {
26 Elf_Shdr shdr;
27 struct section *link;
28 Elf_Sym *symtab;
29 Elf_Rel *reltab;
30 char *strtab;
31};
32static struct section *secs;
33
34static const char * const sym_regex_kernel[S_NSYMTYPES] = {
35/*
36 * Following symbols have been audited. There values are constant and do
37 * not change if bzImage is loaded at a different physical address than
38 * the address for which it has been compiled. Don't warn user about
39 * absolute relocations present w.r.t these symbols.
40 */
41 [S_ABS] =
42 "^(xen_irq_disable_direct_reloc$|"
43 "xen_save_fl_direct_reloc$|"
44 "VDSO|"
45 "__crc_)",
46
47/*
48 * These symbols are known to be relative, even if the linker marks them
49 * as absolute (typically defined outside any section in the linker script.)
50 */
51 [S_REL] =
52 "^(__init_(begin|end)|"
53 "__x86_cpu_dev_(start|end)|"
54 "(__parainstructions|__alt_instructions)(|_end)|"
55 "(__iommu_table|__apicdrivers|__smp_locks)(|_end)|"
56 "__(start|end)_pci_.*|"
57 "__(start|end)_builtin_fw|"
58 "__(start|stop)___ksymtab(|_gpl|_unused|_unused_gpl|_gpl_future)|"
59 "__(start|stop)___kcrctab(|_gpl|_unused|_unused_gpl|_gpl_future)|"
60 "__(start|stop)___param|"
61 "__(start|stop)___modver|"
62 "__(start|stop)___bug_table|"
63 "__tracedata_(start|end)|"
64 "__(start|stop)_notes|"
65 "__end_rodata|"
66 "__initramfs_start|"
67 "(jiffies|jiffies_64)|"
68#if ELF_BITS == 64
69 "__per_cpu_load|"
70 "init_per_cpu__.*|"
71 "__end_rodata_hpage_align|"
72#endif
73 "__vvar_page|"
74 "_end)$"
75};
76
77
78static const char * const sym_regex_realmode[S_NSYMTYPES] = {
79/*
80 * These symbols are known to be relative, even if the linker marks them
81 * as absolute (typically defined outside any section in the linker script.)
82 */
83 [S_REL] =
84 "^pa_",
85
86/*
87 * These are 16-bit segment symbols when compiling 16-bit code.
88 */
89 [S_SEG] =
90 "^real_mode_seg$",
91
92/*
93 * These are offsets belonging to segments, as opposed to linear addresses,
94 * when compiling 16-bit code.
95 */
96 [S_LIN] =
97 "^pa_",
98};
99
100static const char * const *sym_regex;
101
102static regex_t sym_regex_c[S_NSYMTYPES];
103static int is_reloc(enum symtype type, const char *sym_name)
104{
105 return sym_regex[type] &&
106 !regexec(&sym_regex_c[type], sym_name, 0, NULL, 0);
107}
108
109static void regex_init(int use_real_mode)
110{
111 char errbuf[128];
112 int err;
113 int i;
114
115 if (use_real_mode)
116 sym_regex = sym_regex_realmode;
117 else
118 sym_regex = sym_regex_kernel;
119
120 for (i = 0; i < S_NSYMTYPES; i++) {
121 if (!sym_regex[i])
122 continue;
123
124 err = regcomp(&sym_regex_c[i], sym_regex[i],
125 REG_EXTENDED|REG_NOSUB);
126
127 if (err) {
128 regerror(err, &sym_regex_c[i], errbuf, sizeof errbuf);
129 die("%s", errbuf);
130 }
131 }
132}
133
134static const char *sym_type(unsigned type)
135{
136 static const char *type_name[] = {
137#define SYM_TYPE(X) [X] = #X
138 SYM_TYPE(STT_NOTYPE),
139 SYM_TYPE(STT_OBJECT),
140 SYM_TYPE(STT_FUNC),
141 SYM_TYPE(STT_SECTION),
142 SYM_TYPE(STT_FILE),
143 SYM_TYPE(STT_COMMON),
144 SYM_TYPE(STT_TLS),
145#undef SYM_TYPE
146 };
147 const char *name = "unknown sym type name";
148 if (type < ARRAY_SIZE(type_name)) {
149 name = type_name[type];
150 }
151 return name;
152}
153
154static const char *sym_bind(unsigned bind)
155{
156 static const char *bind_name[] = {
157#define SYM_BIND(X) [X] = #X
158 SYM_BIND(STB_LOCAL),
159 SYM_BIND(STB_GLOBAL),
160 SYM_BIND(STB_WEAK),
161#undef SYM_BIND
162 };
163 const char *name = "unknown sym bind name";
164 if (bind < ARRAY_SIZE(bind_name)) {
165 name = bind_name[bind];
166 }
167 return name;
168}
169
170static const char *sym_visibility(unsigned visibility)
171{
172 static const char *visibility_name[] = {
173#define SYM_VISIBILITY(X) [X] = #X
174 SYM_VISIBILITY(STV_DEFAULT),
175 SYM_VISIBILITY(STV_INTERNAL),
176 SYM_VISIBILITY(STV_HIDDEN),
177 SYM_VISIBILITY(STV_PROTECTED),
178#undef SYM_VISIBILITY
179 };
180 const char *name = "unknown sym visibility name";
181 if (visibility < ARRAY_SIZE(visibility_name)) {
182 name = visibility_name[visibility];
183 }
184 return name;
185}
186
187static const char *rel_type(unsigned type)
188{
189 static const char *type_name[] = {
190#define REL_TYPE(X) [X] = #X
191#if ELF_BITS == 64
192 REL_TYPE(R_X86_64_NONE),
193 REL_TYPE(R_X86_64_64),
194 REL_TYPE(R_X86_64_PC32),
195 REL_TYPE(R_X86_64_GOT32),
196 REL_TYPE(R_X86_64_PLT32),
197 REL_TYPE(R_X86_64_COPY),
198 REL_TYPE(R_X86_64_GLOB_DAT),
199 REL_TYPE(R_X86_64_JUMP_SLOT),
200 REL_TYPE(R_X86_64_RELATIVE),
201 REL_TYPE(R_X86_64_GOTPCREL),
202 REL_TYPE(R_X86_64_32),
203 REL_TYPE(R_X86_64_32S),
204 REL_TYPE(R_X86_64_16),
205 REL_TYPE(R_X86_64_PC16),
206 REL_TYPE(R_X86_64_8),
207 REL_TYPE(R_X86_64_PC8),
208#else
209 REL_TYPE(R_386_NONE),
210 REL_TYPE(R_386_32),
211 REL_TYPE(R_386_PC32),
212 REL_TYPE(R_386_GOT32),
213 REL_TYPE(R_386_PLT32),
214 REL_TYPE(R_386_COPY),
215 REL_TYPE(R_386_GLOB_DAT),
216 REL_TYPE(R_386_JMP_SLOT),
217 REL_TYPE(R_386_RELATIVE),
218 REL_TYPE(R_386_GOTOFF),
219 REL_TYPE(R_386_GOTPC),
220 REL_TYPE(R_386_8),
221 REL_TYPE(R_386_PC8),
222 REL_TYPE(R_386_16),
223 REL_TYPE(R_386_PC16),
224#endif
225#undef REL_TYPE
226 };
227 const char *name = "unknown type rel type name";
228 if (type < ARRAY_SIZE(type_name) && type_name[type]) {
229 name = type_name[type];
230 }
231 return name;
232}
233
234static const char *sec_name(unsigned shndx)
235{
236 const char *sec_strtab;
237 const char *name;
238 sec_strtab = secs[ehdr.e_shstrndx].strtab;
239 name = "<noname>";
240 if (shndx < ehdr.e_shnum) {
241 name = sec_strtab + secs[shndx].shdr.sh_name;
242 }
243 else if (shndx == SHN_ABS) {
244 name = "ABSOLUTE";
245 }
246 else if (shndx == SHN_COMMON) {
247 name = "COMMON";
248 }
249 return name;
250}
251
252static const char *sym_name(const char *sym_strtab, Elf_Sym *sym)
253{
254 const char *name;
255 name = "<noname>";
256 if (sym->st_name) {
257 name = sym_strtab + sym->st_name;
258 }
259 else {
260 name = sec_name(sym->st_shndx);
261 }
262 return name;
263}
264
265static Elf_Sym *sym_lookup(const char *symname)
266{
267 int i;
268 for (i = 0; i < ehdr.e_shnum; i++) {
269 struct section *sec = &secs[i];
270 long nsyms;
271 char *strtab;
272 Elf_Sym *symtab;
273 Elf_Sym *sym;
274
275 if (sec->shdr.sh_type != SHT_SYMTAB)
276 continue;
277
278 nsyms = sec->shdr.sh_size/sizeof(Elf_Sym);
279 symtab = sec->symtab;
280 strtab = sec->link->strtab;
281
282 for (sym = symtab; --nsyms >= 0; sym++) {
283 if (!sym->st_name)
284 continue;
285 if (strcmp(symname, strtab + sym->st_name) == 0)
286 return sym;
287 }
288 }
289 return 0;
290}
291
292#if BYTE_ORDER == LITTLE_ENDIAN
293#define le16_to_cpu(val) (val)
294#define le32_to_cpu(val) (val)
295#define le64_to_cpu(val) (val)
296#endif
297#if BYTE_ORDER == BIG_ENDIAN
298#define le16_to_cpu(val) bswap_16(val)
299#define le32_to_cpu(val) bswap_32(val)
300#define le64_to_cpu(val) bswap_64(val)
301#endif
302
303static uint16_t elf16_to_cpu(uint16_t val)
304{
305 return le16_to_cpu(val);
306}
307
308static uint32_t elf32_to_cpu(uint32_t val)
309{
310 return le32_to_cpu(val);
311}
312
313#define elf_half_to_cpu(x) elf16_to_cpu(x)
314#define elf_word_to_cpu(x) elf32_to_cpu(x)
315
316#if ELF_BITS == 64
317static uint64_t elf64_to_cpu(uint64_t val)
318{
319 return le64_to_cpu(val);
320}
321#define elf_addr_to_cpu(x) elf64_to_cpu(x)
322#define elf_off_to_cpu(x) elf64_to_cpu(x)
323#define elf_xword_to_cpu(x) elf64_to_cpu(x)
324#else
325#define elf_addr_to_cpu(x) elf32_to_cpu(x)
326#define elf_off_to_cpu(x) elf32_to_cpu(x)
327#define elf_xword_to_cpu(x) elf32_to_cpu(x)
328#endif
329
330static void read_ehdr(FILE *fp)
331{
332 if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1) {
333 die("Cannot read ELF header: %s\n",
334 strerror(errno));
335 }
336 if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0) {
337 die("No ELF magic\n");
338 }
339 if (ehdr.e_ident[EI_CLASS] != ELF_CLASS) {
340 die("Not a %d bit executable\n", ELF_BITS);
341 }
342 if (ehdr.e_ident[EI_DATA] != ELFDATA2LSB) {
343 die("Not a LSB ELF executable\n");
344 }
345 if (ehdr.e_ident[EI_VERSION] != EV_CURRENT) {
346 die("Unknown ELF version\n");
347 }
348 /* Convert the fields to native endian */
349 ehdr.e_type = elf_half_to_cpu(ehdr.e_type);
350 ehdr.e_machine = elf_half_to_cpu(ehdr.e_machine);
351 ehdr.e_version = elf_word_to_cpu(ehdr.e_version);
352 ehdr.e_entry = elf_addr_to_cpu(ehdr.e_entry);
353 ehdr.e_phoff = elf_off_to_cpu(ehdr.e_phoff);
354 ehdr.e_shoff = elf_off_to_cpu(ehdr.e_shoff);
355 ehdr.e_flags = elf_word_to_cpu(ehdr.e_flags);
356 ehdr.e_ehsize = elf_half_to_cpu(ehdr.e_ehsize);
357 ehdr.e_phentsize = elf_half_to_cpu(ehdr.e_phentsize);
358 ehdr.e_phnum = elf_half_to_cpu(ehdr.e_phnum);
359 ehdr.e_shentsize = elf_half_to_cpu(ehdr.e_shentsize);
360 ehdr.e_shnum = elf_half_to_cpu(ehdr.e_shnum);
361 ehdr.e_shstrndx = elf_half_to_cpu(ehdr.e_shstrndx);
362
363 if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN)) {
364 die("Unsupported ELF header type\n");
365 }
366 if (ehdr.e_machine != ELF_MACHINE) {
367 die("Not for %s\n", ELF_MACHINE_NAME);
368 }
369 if (ehdr.e_version != EV_CURRENT) {
370 die("Unknown ELF version\n");
371 }
372 if (ehdr.e_ehsize != sizeof(Elf_Ehdr)) {
373 die("Bad Elf header size\n");
374 }
375 if (ehdr.e_phentsize != sizeof(Elf_Phdr)) {
376 die("Bad program header entry\n");
377 }
378 if (ehdr.e_shentsize != sizeof(Elf_Shdr)) {
379 die("Bad section header entry\n");
380 }
381 if (ehdr.e_shstrndx >= ehdr.e_shnum) {
382 die("String table index out of bounds\n");
383 }
384}
385
386static void read_shdrs(FILE *fp)
387{
388 int i;
389 Elf_Shdr shdr;
390
391 secs = calloc(ehdr.e_shnum, sizeof(struct section));
392 if (!secs) {
393 die("Unable to allocate %d section headers\n",
394 ehdr.e_shnum);
395 }
396 if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
397 die("Seek to %d failed: %s\n",
398 ehdr.e_shoff, strerror(errno));
399 }
400 for (i = 0; i < ehdr.e_shnum; i++) {
401 struct section *sec = &secs[i];
402 if (fread(&shdr, sizeof shdr, 1, fp) != 1)
403 die("Cannot read ELF section headers %d/%d: %s\n",
404 i, ehdr.e_shnum, strerror(errno));
405 sec->shdr.sh_name = elf_word_to_cpu(shdr.sh_name);
406 sec->shdr.sh_type = elf_word_to_cpu(shdr.sh_type);
407 sec->shdr.sh_flags = elf_xword_to_cpu(shdr.sh_flags);
408 sec->shdr.sh_addr = elf_addr_to_cpu(shdr.sh_addr);
409 sec->shdr.sh_offset = elf_off_to_cpu(shdr.sh_offset);
410 sec->shdr.sh_size = elf_xword_to_cpu(shdr.sh_size);
411 sec->shdr.sh_link = elf_word_to_cpu(shdr.sh_link);
412 sec->shdr.sh_info = elf_word_to_cpu(shdr.sh_info);
413 sec->shdr.sh_addralign = elf_xword_to_cpu(shdr.sh_addralign);
414 sec->shdr.sh_entsize = elf_xword_to_cpu(shdr.sh_entsize);
415 if (sec->shdr.sh_link < ehdr.e_shnum)
416 sec->link = &secs[sec->shdr.sh_link];
417 }
418
419}
420
421static void read_strtabs(FILE *fp)
422{
423 int i;
424 for (i = 0; i < ehdr.e_shnum; i++) {
425 struct section *sec = &secs[i];
426 if (sec->shdr.sh_type != SHT_STRTAB) {
427 continue;
428 }
429 sec->strtab = malloc(sec->shdr.sh_size);
430 if (!sec->strtab) {
431 die("malloc of %d bytes for strtab failed\n",
432 sec->shdr.sh_size);
433 }
434 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
435 die("Seek to %d failed: %s\n",
436 sec->shdr.sh_offset, strerror(errno));
437 }
438 if (fread(sec->strtab, 1, sec->shdr.sh_size, fp)
439 != sec->shdr.sh_size) {
440 die("Cannot read symbol table: %s\n",
441 strerror(errno));
442 }
443 }
444}
445
446static void read_symtabs(FILE *fp)
447{
448 int i,j;
449 for (i = 0; i < ehdr.e_shnum; i++) {
450 struct section *sec = &secs[i];
451 if (sec->shdr.sh_type != SHT_SYMTAB) {
452 continue;
453 }
454 sec->symtab = malloc(sec->shdr.sh_size);
455 if (!sec->symtab) {
456 die("malloc of %d bytes for symtab failed\n",
457 sec->shdr.sh_size);
458 }
459 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
460 die("Seek to %d failed: %s\n",
461 sec->shdr.sh_offset, strerror(errno));
462 }
463 if (fread(sec->symtab, 1, sec->shdr.sh_size, fp)
464 != sec->shdr.sh_size) {
465 die("Cannot read symbol table: %s\n",
466 strerror(errno));
467 }
468 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Sym); j++) {
469 Elf_Sym *sym = &sec->symtab[j];
470 sym->st_name = elf_word_to_cpu(sym->st_name);
471 sym->st_value = elf_addr_to_cpu(sym->st_value);
472 sym->st_size = elf_xword_to_cpu(sym->st_size);
473 sym->st_shndx = elf_half_to_cpu(sym->st_shndx);
474 }
475 }
476}
477
478
479static void read_relocs(FILE *fp)
480{
481 int i,j;
482 for (i = 0; i < ehdr.e_shnum; i++) {
483 struct section *sec = &secs[i];
484 if (sec->shdr.sh_type != SHT_REL_TYPE) {
485 continue;
486 }
487 sec->reltab = malloc(sec->shdr.sh_size);
488 if (!sec->reltab) {
489 die("malloc of %d bytes for relocs failed\n",
490 sec->shdr.sh_size);
491 }
492 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
493 die("Seek to %d failed: %s\n",
494 sec->shdr.sh_offset, strerror(errno));
495 }
496 if (fread(sec->reltab, 1, sec->shdr.sh_size, fp)
497 != sec->shdr.sh_size) {
498 die("Cannot read symbol table: %s\n",
499 strerror(errno));
500 }
501 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
502 Elf_Rel *rel = &sec->reltab[j];
503 rel->r_offset = elf_addr_to_cpu(rel->r_offset);
504 rel->r_info = elf_xword_to_cpu(rel->r_info);
505#if (SHT_REL_TYPE == SHT_RELA)
506 rel->r_addend = elf_xword_to_cpu(rel->r_addend);
507#endif
508 }
509 }
510}
511
512
513static void print_absolute_symbols(void)
514{
515 int i;
516 const char *format;
517
518 if (ELF_BITS == 64)
519 format = "%5d %016"PRIx64" %5"PRId64" %10s %10s %12s %s\n";
520 else
521 format = "%5d %08"PRIx32" %5"PRId32" %10s %10s %12s %s\n";
522
523 printf("Absolute symbols\n");
524 printf(" Num: Value Size Type Bind Visibility Name\n");
525 for (i = 0; i < ehdr.e_shnum; i++) {
526 struct section *sec = &secs[i];
527 char *sym_strtab;
528 int j;
529
530 if (sec->shdr.sh_type != SHT_SYMTAB) {
531 continue;
532 }
533 sym_strtab = sec->link->strtab;
534 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Sym); j++) {
535 Elf_Sym *sym;
536 const char *name;
537 sym = &sec->symtab[j];
538 name = sym_name(sym_strtab, sym);
539 if (sym->st_shndx != SHN_ABS) {
540 continue;
541 }
542 printf(format,
543 j, sym->st_value, sym->st_size,
544 sym_type(ELF_ST_TYPE(sym->st_info)),
545 sym_bind(ELF_ST_BIND(sym->st_info)),
546 sym_visibility(ELF_ST_VISIBILITY(sym->st_other)),
547 name);
548 }
549 }
550 printf("\n");
551}
552
553static void print_absolute_relocs(void)
554{
555 int i, printed = 0;
556 const char *format;
557
558 if (ELF_BITS == 64)
559 format = "%016"PRIx64" %016"PRIx64" %10s %016"PRIx64" %s\n";
560 else
561 format = "%08"PRIx32" %08"PRIx32" %10s %08"PRIx32" %s\n";
562
563 for (i = 0; i < ehdr.e_shnum; i++) {
564 struct section *sec = &secs[i];
565 struct section *sec_applies, *sec_symtab;
566 char *sym_strtab;
567 Elf_Sym *sh_symtab;
568 int j;
569 if (sec->shdr.sh_type != SHT_REL_TYPE) {
570 continue;
571 }
572 sec_symtab = sec->link;
573 sec_applies = &secs[sec->shdr.sh_info];
574 if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) {
575 continue;
576 }
577 sh_symtab = sec_symtab->symtab;
578 sym_strtab = sec_symtab->link->strtab;
579 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
580 Elf_Rel *rel;
581 Elf_Sym *sym;
582 const char *name;
583 rel = &sec->reltab[j];
584 sym = &sh_symtab[ELF_R_SYM(rel->r_info)];
585 name = sym_name(sym_strtab, sym);
586 if (sym->st_shndx != SHN_ABS) {
587 continue;
588 }
589
590 /* Absolute symbols are not relocated if bzImage is
591 * loaded at a non-compiled address. Display a warning
592 * to user at compile time about the absolute
593 * relocations present.
594 *
595 * User need to audit the code to make sure
596 * some symbols which should have been section
597 * relative have not become absolute because of some
598 * linker optimization or wrong programming usage.
599 *
600 * Before warning check if this absolute symbol
601 * relocation is harmless.
602 */
603 if (is_reloc(S_ABS, name) || is_reloc(S_REL, name))
604 continue;
605
606 if (!printed) {
607 printf("WARNING: Absolute relocations"
608 " present\n");
609 printf("Offset Info Type Sym.Value "
610 "Sym.Name\n");
611 printed = 1;
612 }
613
614 printf(format,
615 rel->r_offset,
616 rel->r_info,
617 rel_type(ELF_R_TYPE(rel->r_info)),
618 sym->st_value,
619 name);
620 }
621 }
622
623 if (printed)
624 printf("\n");
625}
626
627static void add_reloc(struct relocs *r, uint32_t offset)
628{
629 if (r->count == r->size) {
630 unsigned long newsize = r->size + 50000;
631 void *mem = realloc(r->offset, newsize * sizeof(r->offset[0]));
632
633 if (!mem)
634 die("realloc of %ld entries for relocs failed\n",
635 newsize);
636 r->offset = mem;
637 r->size = newsize;
638 }
639 r->offset[r->count++] = offset;
640}
641
642static void walk_relocs(int (*process)(struct section *sec, Elf_Rel *rel,
643 Elf_Sym *sym, const char *symname))
644{
645 int i;
646 /* Walk through the relocations */
647 for (i = 0; i < ehdr.e_shnum; i++) {
648 char *sym_strtab;
649 Elf_Sym *sh_symtab;
650 struct section *sec_applies, *sec_symtab;
651 int j;
652 struct section *sec = &secs[i];
653
654 if (sec->shdr.sh_type != SHT_REL_TYPE) {
655 continue;
656 }
657 sec_symtab = sec->link;
658 sec_applies = &secs[sec->shdr.sh_info];
659 if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) {
660 continue;
661 }
662 sh_symtab = sec_symtab->symtab;
663 sym_strtab = sec_symtab->link->strtab;
664 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
665 Elf_Rel *rel = &sec->reltab[j];
666 Elf_Sym *sym = &sh_symtab[ELF_R_SYM(rel->r_info)];
667 const char *symname = sym_name(sym_strtab, sym);
668
669 process(sec, rel, sym, symname);
670 }
671 }
672}
673
674/*
675 * The .data..percpu section is a special case for x86_64 SMP kernels.
676 * It is used to initialize the actual per_cpu areas and to provide
677 * definitions for the per_cpu variables that correspond to their offsets
678 * within the percpu area. Since the values of all of the symbols need
679 * to be offsets from the start of the per_cpu area the virtual address
680 * (sh_addr) of .data..percpu is 0 in SMP kernels.
681 *
682 * This means that:
683 *
684 * Relocations that reference symbols in the per_cpu area do not
685 * need further relocation (since the value is an offset relative
686 * to the start of the per_cpu area that does not change).
687 *
688 * Relocations that apply to the per_cpu area need to have their
689 * offset adjusted by by the value of __per_cpu_load to make them
690 * point to the correct place in the loaded image (because the
691 * virtual address of .data..percpu is 0).
692 *
693 * For non SMP kernels .data..percpu is linked as part of the normal
694 * kernel data and does not require special treatment.
695 *
696 */
697static int per_cpu_shndx = -1;
698Elf_Addr per_cpu_load_addr;
699
700static void percpu_init(void)
701{
702 int i;
703 for (i = 0; i < ehdr.e_shnum; i++) {
704 ElfW(Sym) *sym;
705 if (strcmp(sec_name(i), ".data..percpu"))
706 continue;
707
708 if (secs[i].shdr.sh_addr != 0) /* non SMP kernel */
709 return;
710
711 sym = sym_lookup("__per_cpu_load");
712 if (!sym)
713 die("can't find __per_cpu_load\n");
714
715 per_cpu_shndx = i;
716 per_cpu_load_addr = sym->st_value;
717 return;
718 }
719}
720
721#if ELF_BITS == 64
722
723/*
724 * Check to see if a symbol lies in the .data..percpu section.
725 *
726 * The linker incorrectly associates some symbols with the
727 * .data..percpu section so we also need to check the symbol
728 * name to make sure that we classify the symbol correctly.
729 *
730 * The GNU linker incorrectly associates:
731 * __init_begin
732 * __per_cpu_load
733 *
734 * The "gold" linker incorrectly associates:
735 * init_per_cpu__irq_stack_union
736 * init_per_cpu__gdt_page
737 */
738static int is_percpu_sym(ElfW(Sym) *sym, const char *symname)
739{
740 return (sym->st_shndx == per_cpu_shndx) &&
741 strcmp(symname, "__init_begin") &&
742 strcmp(symname, "__per_cpu_load") &&
743 strncmp(symname, "init_per_cpu_", 13);
744}
745
746
747static int do_reloc64(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym,
748 const char *symname)
749{
750 unsigned r_type = ELF64_R_TYPE(rel->r_info);
751 ElfW(Addr) offset = rel->r_offset;
752 int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
753
754 if (sym->st_shndx == SHN_UNDEF)
755 return 0;
756
757 /*
758 * Adjust the offset if this reloc applies to the percpu section.
759 */
760 if (sec->shdr.sh_info == per_cpu_shndx)
761 offset += per_cpu_load_addr;
762
763 switch (r_type) {
764 case R_X86_64_NONE:
765 case R_X86_64_PC32:
766 /*
767 * NONE can be ignored and PC relative relocations don't
768 * need to be adjusted.
769 */
770 break;
771
772 case R_X86_64_32:
773 case R_X86_64_32S:
774 case R_X86_64_64:
775 /*
776 * References to the percpu area don't need to be adjusted.
777 */
778 if (is_percpu_sym(sym, symname))
779 break;
780
781 if (shn_abs) {
782 /*
783 * Whitelisted absolute symbols do not require
784 * relocation.
785 */
786 if (is_reloc(S_ABS, symname))
787 break;
788
789 die("Invalid absolute %s relocation: %s\n",
790 rel_type(r_type), symname);
791 break;
792 }
793
794 /*
795 * Relocation offsets for 64 bit kernels are output
796 * as 32 bits and sign extended back to 64 bits when
797 * the relocations are processed.
798 * Make sure that the offset will fit.
799 */
800 if ((int32_t)offset != (int64_t)offset)
801 die("Relocation offset doesn't fit in 32 bits\n");
802
803 if (r_type == R_X86_64_64)
804 add_reloc(&relocs64, offset);
805 else
806 add_reloc(&relocs32, offset);
807 break;
808
809 default:
810 die("Unsupported relocation type: %s (%d)\n",
811 rel_type(r_type), r_type);
812 break;
813 }
814
815 return 0;
816}
817
818#else
819
820static int do_reloc32(struct section *sec, Elf_Rel *rel, Elf_Sym *sym,
821 const char *symname)
822{
823 unsigned r_type = ELF32_R_TYPE(rel->r_info);
824 int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
825
826 switch (r_type) {
827 case R_386_NONE:
828 case R_386_PC32:
829 case R_386_PC16:
830 case R_386_PC8:
831 /*
832 * NONE can be ignored and PC relative relocations don't
833 * need to be adjusted.
834 */
835 break;
836
837 case R_386_32:
838 if (shn_abs) {
839 /*
840 * Whitelisted absolute symbols do not require
841 * relocation.
842 */
843 if (is_reloc(S_ABS, symname))
844 break;
845
846 die("Invalid absolute %s relocation: %s\n",
847 rel_type(r_type), symname);
848 break;
849 }
850
851 add_reloc(&relocs32, rel->r_offset);
852 break;
853
854 default:
855 die("Unsupported relocation type: %s (%d)\n",
856 rel_type(r_type), r_type);
857 break;
858 }
859
860 return 0;
861}
862
863static int do_reloc_real(struct section *sec, Elf_Rel *rel, Elf_Sym *sym,
864 const char *symname)
865{
866 unsigned r_type = ELF32_R_TYPE(rel->r_info);
867 int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
868
869 switch (r_type) {
870 case R_386_NONE:
871 case R_386_PC32:
872 case R_386_PC16:
873 case R_386_PC8:
874 /*
875 * NONE can be ignored and PC relative relocations don't
876 * need to be adjusted.
877 */
878 break;
879
880 case R_386_16:
881 if (shn_abs) {
882 /*
883 * Whitelisted absolute symbols do not require
884 * relocation.
885 */
886 if (is_reloc(S_ABS, symname))
887 break;
888
889 if (is_reloc(S_SEG, symname)) {
890 add_reloc(&relocs16, rel->r_offset);
891 break;
892 }
893 } else {
894 if (!is_reloc(S_LIN, symname))
895 break;
896 }
897 die("Invalid %s %s relocation: %s\n",
898 shn_abs ? "absolute" : "relative",
899 rel_type(r_type), symname);
900 break;
901
902 case R_386_32:
903 if (shn_abs) {
904 /*
905 * Whitelisted absolute symbols do not require
906 * relocation.
907 */
908 if (is_reloc(S_ABS, symname))
909 break;
910
911 if (is_reloc(S_REL, symname)) {
912 add_reloc(&relocs32, rel->r_offset);
913 break;
914 }
915 } else {
916 if (is_reloc(S_LIN, symname))
917 add_reloc(&relocs32, rel->r_offset);
918 break;
919 }
920 die("Invalid %s %s relocation: %s\n",
921 shn_abs ? "absolute" : "relative",
922 rel_type(r_type), symname);
923 break;
924
925 default:
926 die("Unsupported relocation type: %s (%d)\n",
927 rel_type(r_type), r_type);
928 break;
929 }
930
931 return 0;
932}
933
934#endif
935
936static int cmp_relocs(const void *va, const void *vb)
937{
938 const uint32_t *a, *b;
939 a = va; b = vb;
940 return (*a == *b)? 0 : (*a > *b)? 1 : -1;
941}
942
943static void sort_relocs(struct relocs *r)
944{
945 qsort(r->offset, r->count, sizeof(r->offset[0]), cmp_relocs);
946}
947
948static int write32(uint32_t v, FILE *f)
949{
950 unsigned char buf[4];
951
952 put_unaligned_le32(v, buf);
953 return fwrite(buf, 1, 4, f) == 4 ? 0 : -1;
954}
955
956static int write32_as_text(uint32_t v, FILE *f)
957{
958 return fprintf(f, "\t.long 0x%08"PRIx32"\n", v) > 0 ? 0 : -1;
959}
960
961static void emit_relocs(int as_text, int use_real_mode)
962{
963 int i;
964 int (*write_reloc)(uint32_t, FILE *) = write32;
965 int (*do_reloc)(struct section *sec, Elf_Rel *rel, Elf_Sym *sym,
966 const char *symname);
967
968#if ELF_BITS == 64
969 if (!use_real_mode)
970 do_reloc = do_reloc64;
971 else
972 die("--realmode not valid for a 64-bit ELF file");
973#else
974 if (!use_real_mode)
975 do_reloc = do_reloc32;
976 else
977 do_reloc = do_reloc_real;
978#endif
979
980 /* Collect up the relocations */
981 walk_relocs(do_reloc);
982
983 if (relocs16.count && !use_real_mode)
984 die("Segment relocations found but --realmode not specified\n");
985
986 /* Order the relocations for more efficient processing */
987 sort_relocs(&relocs16);
988 sort_relocs(&relocs32);
989 sort_relocs(&relocs64);
990
991 /* Print the relocations */
992 if (as_text) {
993 /* Print the relocations in a form suitable that
994 * gas will like.
995 */
996 printf(".section \".data.reloc\",\"a\"\n");
997 printf(".balign 4\n");
998 write_reloc = write32_as_text;
999 }
1000
1001 if (use_real_mode) {
1002 write_reloc(relocs16.count, stdout);
1003 for (i = 0; i < relocs16.count; i++)
1004 write_reloc(relocs16.offset[i], stdout);
1005
1006 write_reloc(relocs32.count, stdout);
1007 for (i = 0; i < relocs32.count; i++)
1008 write_reloc(relocs32.offset[i], stdout);
1009 } else {
1010 if (ELF_BITS == 64) {
1011 /* Print a stop */
1012 write_reloc(0, stdout);
1013
1014 /* Now print each relocation */
1015 for (i = 0; i < relocs64.count; i++)
1016 write_reloc(relocs64.offset[i], stdout);
1017 }
1018
1019 /* Print a stop */
1020 write_reloc(0, stdout);
1021
1022 /* Now print each relocation */
1023 for (i = 0; i < relocs32.count; i++)
1024 write_reloc(relocs32.offset[i], stdout);
1025 }
1026}
1027
1028/*
1029 * As an aid to debugging problems with different linkers
1030 * print summary information about the relocs.
1031 * Since different linkers tend to emit the sections in
1032 * different orders we use the section names in the output.
1033 */
1034static int do_reloc_info(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym,
1035 const char *symname)
1036{
1037 printf("%s\t%s\t%s\t%s\n",
1038 sec_name(sec->shdr.sh_info),
1039 rel_type(ELF_R_TYPE(rel->r_info)),
1040 symname,
1041 sec_name(sym->st_shndx));
1042 return 0;
1043}
1044
1045static void print_reloc_info(void)
1046{
1047 printf("reloc section\treloc type\tsymbol\tsymbol section\n");
1048 walk_relocs(do_reloc_info);
1049}
1050
1051#if ELF_BITS == 64
1052# define process process_64
1053#else
1054# define process process_32
1055#endif
1056
1057void process(FILE *fp, int use_real_mode, int as_text,
1058 int show_absolute_syms, int show_absolute_relocs,
1059 int show_reloc_info)
1060{
1061 regex_init(use_real_mode);
1062 read_ehdr(fp);
1063 read_shdrs(fp);
1064 read_strtabs(fp);
1065 read_symtabs(fp);
1066 read_relocs(fp);
1067 if (ELF_BITS == 64)
1068 percpu_init();
1069 if (show_absolute_syms) {
1070 print_absolute_symbols();
1071 return;
1072 }
1073 if (show_absolute_relocs) {
1074 print_absolute_relocs();
1075 return;
1076 }
1077 if (show_reloc_info) {
1078 print_reloc_info();
1079 return;
1080 }
1081 emit_relocs(as_text, use_real_mode);
1082}