projects/linux·blob v6.8-rc2 · refs

2301 lines · 56.9 KiB

1/* Postprocess module symbol versions
2 *
3 * Copyright 2003 Kai Germaschewski
4 * Copyright 2002-2004 Rusty Russell, IBM Corporation
5 * Copyright 2006-2008 Sam Ravnborg
6 * Based in part on module-init-tools/depmod.c,file2alias
7 *
8 * This software may be used and distributed according to the terms
9 * of the GNU General Public License, incorporated herein by reference.
10 *
11 * Usage: modpost vmlinux module1.o module2.o ...
12 */
13
14#define _GNU_SOURCE
15#include <elf.h>
16#include <fnmatch.h>
17#include <stdio.h>
18#include <ctype.h>
19#include <string.h>
20#include <limits.h>
21#include <stdbool.h>
22#include <errno.h>
23#include "modpost.h"
24#include "../../include/linux/license.h"
25
26static bool module_enabled;
27/* Are we using CONFIG_MODVERSIONS? */
28static bool modversions;
29/* Is CONFIG_MODULE_SRCVERSION_ALL set? */
30static bool all_versions;
31/* If we are modposting external module set to 1 */
32static bool external_module;
33/* Only warn about unresolved symbols */
34static bool warn_unresolved;
35
36static int sec_mismatch_count;
37static bool sec_mismatch_warn_only = true;
38/* Trim EXPORT_SYMBOLs that are unused by in-tree modules */
39static bool trim_unused_exports;
40
41/* ignore missing files */
42static bool ignore_missing_files;
43/* If set to 1, only warn (instead of error) about missing ns imports */
44static bool allow_missing_ns_imports;
45
46static bool error_occurred;
47
48static bool extra_warn;
49
50/*
51 * Cut off the warnings when there are too many. This typically occurs when
52 * vmlinux is missing. ('make modules' without building vmlinux.)
53 */
54#define MAX_UNRESOLVED_REPORTS 10
55static unsigned int nr_unresolved;
56
57/* In kernel, this size is defined in linux/module.h;
58 * here we use Elf_Addr instead of long for covering cross-compile
59 */
60
61#define MODULE_NAME_LEN (64 - sizeof(Elf_Addr))
62
63void modpost_log(enum loglevel loglevel, const char *fmt, ...)
64{
65 va_list arglist;
66
67 switch (loglevel) {
68 case LOG_WARN:
69 fprintf(stderr, "WARNING: ");
70 break;
71 case LOG_ERROR:
72 fprintf(stderr, "ERROR: ");
73 break;
74 case LOG_FATAL:
75 fprintf(stderr, "FATAL: ");
76 break;
77 default: /* invalid loglevel, ignore */
78 break;
79 }
80
81 fprintf(stderr, "modpost: ");
82
83 va_start(arglist, fmt);
84 vfprintf(stderr, fmt, arglist);
85 va_end(arglist);
86
87 if (loglevel == LOG_FATAL)
88 exit(1);
89 if (loglevel == LOG_ERROR)
90 error_occurred = true;
91}
92
93void __attribute__((alias("modpost_log")))
94modpost_log_noret(enum loglevel loglevel, const char *fmt, ...);
95
96static inline bool strends(const char *str, const char *postfix)
97{
98 if (strlen(str) < strlen(postfix))
99 return false;
100
101 return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0;
102}
103
104void *do_nofail(void *ptr, const char *expr)
105{
106 if (!ptr)
107 fatal("Memory allocation failure: %s.\n", expr);
108
109 return ptr;
110}
111
112char *read_text_file(const char *filename)
113{
114 struct stat st;
115 size_t nbytes;
116 int fd;
117 char *buf;
118
119 fd = open(filename, O_RDONLY);
120 if (fd < 0) {
121 perror(filename);
122 exit(1);
123 }
124
125 if (fstat(fd, &st) < 0) {
126 perror(filename);
127 exit(1);
128 }
129
130 buf = NOFAIL(malloc(st.st_size + 1));
131
132 nbytes = st.st_size;
133
134 while (nbytes) {
135 ssize_t bytes_read;
136
137 bytes_read = read(fd, buf, nbytes);
138 if (bytes_read < 0) {
139 perror(filename);
140 exit(1);
141 }
142
143 nbytes -= bytes_read;
144 }
145 buf[st.st_size] = '\0';
146
147 close(fd);
148
149 return buf;
150}
151
152char *get_line(char **stringp)
153{
154 char *orig = *stringp, *next;
155
156 /* do not return the unwanted extra line at EOF */
157 if (!orig || *orig == '\0')
158 return NULL;
159
160 /* don't use strsep here, it is not available everywhere */
161 next = strchr(orig, '\n');
162 if (next)
163 *next++ = '\0';
164
165 *stringp = next;
166
167 return orig;
168}
169
170/* A list of all modules we processed */
171LIST_HEAD(modules);
172
173static struct module *find_module(const char *modname)
174{
175 struct module *mod;
176
177 list_for_each_entry(mod, &modules, list) {
178 if (strcmp(mod->name, modname) == 0)
179 return mod;
180 }
181 return NULL;
182}
183
184static struct module *new_module(const char *name, size_t namelen)
185{
186 struct module *mod;
187
188 mod = NOFAIL(malloc(sizeof(*mod) + namelen + 1));
189 memset(mod, 0, sizeof(*mod));
190
191 INIT_LIST_HEAD(&mod->exported_symbols);
192 INIT_LIST_HEAD(&mod->unresolved_symbols);
193 INIT_LIST_HEAD(&mod->missing_namespaces);
194 INIT_LIST_HEAD(&mod->imported_namespaces);
195
196 memcpy(mod->name, name, namelen);
197 mod->name[namelen] = '\0';
198 mod->is_vmlinux = (strcmp(mod->name, "vmlinux") == 0);
199
200 /*
201 * Set mod->is_gpl_compatible to true by default. If MODULE_LICENSE()
202 * is missing, do not check the use for EXPORT_SYMBOL_GPL() becasue
203 * modpost will exit wiht error anyway.
204 */
205 mod->is_gpl_compatible = true;
206
207 list_add_tail(&mod->list, &modules);
208
209 return mod;
210}
211
212/* A hash of all exported symbols,
213 * struct symbol is also used for lists of unresolved symbols */
214
215#define SYMBOL_HASH_SIZE 1024
216
217struct symbol {
218 struct symbol *next;
219 struct list_head list; /* link to module::exported_symbols or module::unresolved_symbols */
220 struct module *module;
221 char *namespace;
222 unsigned int crc;
223 bool crc_valid;
224 bool weak;
225 bool is_func;
226 bool is_gpl_only; /* exported by EXPORT_SYMBOL_GPL */
227 bool used; /* there exists a user of this symbol */
228 char name[];
229};
230
231static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
232
233/* This is based on the hash algorithm from gdbm, via tdb */
234static inline unsigned int tdb_hash(const char *name)
235{
236 unsigned value; /* Used to compute the hash value. */
237 unsigned i; /* Used to cycle through random values. */
238
239 /* Set the initial value from the key size. */
240 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++)
241 value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
242
243 return (1103515243 * value + 12345);
244}
245
246/**
247 * Allocate a new symbols for use in the hash of exported symbols or
248 * the list of unresolved symbols per module
249 **/
250static struct symbol *alloc_symbol(const char *name)
251{
252 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
253
254 memset(s, 0, sizeof(*s));
255 strcpy(s->name, name);
256
257 return s;
258}
259
260/* For the hash of exported symbols */
261static void hash_add_symbol(struct symbol *sym)
262{
263 unsigned int hash;
264
265 hash = tdb_hash(sym->name) % SYMBOL_HASH_SIZE;
266 sym->next = symbolhash[hash];
267 symbolhash[hash] = sym;
268}
269
270static void sym_add_unresolved(const char *name, struct module *mod, bool weak)
271{
272 struct symbol *sym;
273
274 sym = alloc_symbol(name);
275 sym->weak = weak;
276
277 list_add_tail(&sym->list, &mod->unresolved_symbols);
278}
279
280static struct symbol *sym_find_with_module(const char *name, struct module *mod)
281{
282 struct symbol *s;
283
284 /* For our purposes, .foo matches foo. PPC64 needs this. */
285 if (name[0] == '.')
286 name++;
287
288 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
289 if (strcmp(s->name, name) == 0 && (!mod || s->module == mod))
290 return s;
291 }
292 return NULL;
293}
294
295static struct symbol *find_symbol(const char *name)
296{
297 return sym_find_with_module(name, NULL);
298}
299
300struct namespace_list {
301 struct list_head list;
302 char namespace[];
303};
304
305static bool contains_namespace(struct list_head *head, const char *namespace)
306{
307 struct namespace_list *list;
308
309 /*
310 * The default namespace is null string "", which is always implicitly
311 * contained.
312 */
313 if (!namespace[0])
314 return true;
315
316 list_for_each_entry(list, head, list) {
317 if (!strcmp(list->namespace, namespace))
318 return true;
319 }
320
321 return false;
322}
323
324static void add_namespace(struct list_head *head, const char *namespace)
325{
326 struct namespace_list *ns_entry;
327
328 if (!contains_namespace(head, namespace)) {
329 ns_entry = NOFAIL(malloc(sizeof(*ns_entry) +
330 strlen(namespace) + 1));
331 strcpy(ns_entry->namespace, namespace);
332 list_add_tail(&ns_entry->list, head);
333 }
334}
335
336static void *sym_get_data_by_offset(const struct elf_info *info,
337 unsigned int secindex, unsigned long offset)
338{
339 Elf_Shdr *sechdr = &info->sechdrs[secindex];
340
341 return (void *)info->hdr + sechdr->sh_offset + offset;
342}
343
344void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym)
345{
346 return sym_get_data_by_offset(info, get_secindex(info, sym),
347 sym->st_value);
348}
349
350static const char *sech_name(const struct elf_info *info, Elf_Shdr *sechdr)
351{
352 return sym_get_data_by_offset(info, info->secindex_strings,
353 sechdr->sh_name);
354}
355
356static const char *sec_name(const struct elf_info *info, unsigned int secindex)
357{
358 /*
359 * If sym->st_shndx is a special section index, there is no
360 * corresponding section header.
361 * Return "" if the index is out of range of info->sechdrs[] array.
362 */
363 if (secindex >= info->num_sections)
364 return "";
365
366 return sech_name(info, &info->sechdrs[secindex]);
367}
368
369#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
370
371static struct symbol *sym_add_exported(const char *name, struct module *mod,
372 bool gpl_only, const char *namespace)
373{
374 struct symbol *s = find_symbol(name);
375
376 if (s && (!external_module || s->module->is_vmlinux || s->module == mod)) {
377 error("%s: '%s' exported twice. Previous export was in %s%s\n",
378 mod->name, name, s->module->name,
379 s->module->is_vmlinux ? "" : ".ko");
380 }
381
382 s = alloc_symbol(name);
383 s->module = mod;
384 s->is_gpl_only = gpl_only;
385 s->namespace = NOFAIL(strdup(namespace));
386 list_add_tail(&s->list, &mod->exported_symbols);
387 hash_add_symbol(s);
388
389 return s;
390}
391
392static void sym_set_crc(struct symbol *sym, unsigned int crc)
393{
394 sym->crc = crc;
395 sym->crc_valid = true;
396}
397
398static void *grab_file(const char *filename, size_t *size)
399{
400 struct stat st;
401 void *map = MAP_FAILED;
402 int fd;
403
404 fd = open(filename, O_RDONLY);
405 if (fd < 0)
406 return NULL;
407 if (fstat(fd, &st))
408 goto failed;
409
410 *size = st.st_size;
411 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
412
413failed:
414 close(fd);
415 if (map == MAP_FAILED)
416 return NULL;
417 return map;
418}
419
420static void release_file(void *file, size_t size)
421{
422 munmap(file, size);
423}
424
425static int parse_elf(struct elf_info *info, const char *filename)
426{
427 unsigned int i;
428 Elf_Ehdr *hdr;
429 Elf_Shdr *sechdrs;
430 Elf_Sym *sym;
431 const char *secstrings;
432 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
433
434 hdr = grab_file(filename, &info->size);
435 if (!hdr) {
436 if (ignore_missing_files) {
437 fprintf(stderr, "%s: %s (ignored)\n", filename,
438 strerror(errno));
439 return 0;
440 }
441 perror(filename);
442 exit(1);
443 }
444 info->hdr = hdr;
445 if (info->size < sizeof(*hdr)) {
446 /* file too small, assume this is an empty .o file */
447 return 0;
448 }
449 /* Is this a valid ELF file? */
450 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
451 (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
452 (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
453 (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
454 /* Not an ELF file - silently ignore it */
455 return 0;
456 }
457 /* Fix endianness in ELF header */
458 hdr->e_type = TO_NATIVE(hdr->e_type);
459 hdr->e_machine = TO_NATIVE(hdr->e_machine);
460 hdr->e_version = TO_NATIVE(hdr->e_version);
461 hdr->e_entry = TO_NATIVE(hdr->e_entry);
462 hdr->e_phoff = TO_NATIVE(hdr->e_phoff);
463 hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
464 hdr->e_flags = TO_NATIVE(hdr->e_flags);
465 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize);
466 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
467 hdr->e_phnum = TO_NATIVE(hdr->e_phnum);
468 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
469 hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
470 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
471 sechdrs = (void *)hdr + hdr->e_shoff;
472 info->sechdrs = sechdrs;
473
474 /* modpost only works for relocatable objects */
475 if (hdr->e_type != ET_REL)
476 fatal("%s: not relocatable object.", filename);
477
478 /* Check if file offset is correct */
479 if (hdr->e_shoff > info->size)
480 fatal("section header offset=%lu in file '%s' is bigger than filesize=%zu\n",
481 (unsigned long)hdr->e_shoff, filename, info->size);
482
483 if (hdr->e_shnum == SHN_UNDEF) {
484 /*
485 * There are more than 64k sections,
486 * read count from .sh_size.
487 */
488 info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
489 }
490 else {
491 info->num_sections = hdr->e_shnum;
492 }
493 if (hdr->e_shstrndx == SHN_XINDEX) {
494 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
495 }
496 else {
497 info->secindex_strings = hdr->e_shstrndx;
498 }
499
500 /* Fix endianness in section headers */
501 for (i = 0; i < info->num_sections; i++) {
502 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
503 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
504 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
505 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
506 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
507 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
508 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
509 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
510 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
511 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
512 }
513 /* Find symbol table. */
514 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
515 for (i = 1; i < info->num_sections; i++) {
516 const char *secname;
517 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
518
519 if (!nobits && sechdrs[i].sh_offset > info->size)
520 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > sizeof(*hrd)=%zu\n",
521 filename, (unsigned long)sechdrs[i].sh_offset,
522 sizeof(*hdr));
523
524 secname = secstrings + sechdrs[i].sh_name;
525 if (strcmp(secname, ".modinfo") == 0) {
526 if (nobits)
527 fatal("%s has NOBITS .modinfo\n", filename);
528 info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
529 info->modinfo_len = sechdrs[i].sh_size;
530 } else if (!strcmp(secname, ".export_symbol")) {
531 info->export_symbol_secndx = i;
532 }
533
534 if (sechdrs[i].sh_type == SHT_SYMTAB) {
535 unsigned int sh_link_idx;
536 symtab_idx = i;
537 info->symtab_start = (void *)hdr +
538 sechdrs[i].sh_offset;
539 info->symtab_stop = (void *)hdr +
540 sechdrs[i].sh_offset + sechdrs[i].sh_size;
541 sh_link_idx = sechdrs[i].sh_link;
542 info->strtab = (void *)hdr +
543 sechdrs[sh_link_idx].sh_offset;
544 }
545
546 /* 32bit section no. table? ("more than 64k sections") */
547 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
548 symtab_shndx_idx = i;
549 info->symtab_shndx_start = (void *)hdr +
550 sechdrs[i].sh_offset;
551 info->symtab_shndx_stop = (void *)hdr +
552 sechdrs[i].sh_offset + sechdrs[i].sh_size;
553 }
554 }
555 if (!info->symtab_start)
556 fatal("%s has no symtab?\n", filename);
557
558 /* Fix endianness in symbols */
559 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
560 sym->st_shndx = TO_NATIVE(sym->st_shndx);
561 sym->st_name = TO_NATIVE(sym->st_name);
562 sym->st_value = TO_NATIVE(sym->st_value);
563 sym->st_size = TO_NATIVE(sym->st_size);
564 }
565
566 if (symtab_shndx_idx != ~0U) {
567 Elf32_Word *p;
568 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
569 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
570 filename, sechdrs[symtab_shndx_idx].sh_link,
571 symtab_idx);
572 /* Fix endianness */
573 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
574 p++)
575 *p = TO_NATIVE(*p);
576 }
577
578 symsearch_init(info);
579
580 return 1;
581}
582
583static void parse_elf_finish(struct elf_info *info)
584{
585 symsearch_finish(info);
586 release_file(info->hdr, info->size);
587}
588
589static int ignore_undef_symbol(struct elf_info *info, const char *symname)
590{
591 /* ignore __this_module, it will be resolved shortly */
592 if (strcmp(symname, "__this_module") == 0)
593 return 1;
594 /* ignore global offset table */
595 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
596 return 1;
597 if (info->hdr->e_machine == EM_PPC)
598 /* Special register function linked on all modules during final link of .ko */
599 if (strstarts(symname, "_restgpr_") ||
600 strstarts(symname, "_savegpr_") ||
601 strstarts(symname, "_rest32gpr_") ||
602 strstarts(symname, "_save32gpr_") ||
603 strstarts(symname, "_restvr_") ||
604 strstarts(symname, "_savevr_"))
605 return 1;
606 if (info->hdr->e_machine == EM_PPC64)
607 /* Special register function linked on all modules during final link of .ko */
608 if (strstarts(symname, "_restgpr0_") ||
609 strstarts(symname, "_savegpr0_") ||
610 strstarts(symname, "_restvr_") ||
611 strstarts(symname, "_savevr_") ||
612 strcmp(symname, ".TOC.") == 0)
613 return 1;
614
615 if (info->hdr->e_machine == EM_S390)
616 /* Expoline thunks are linked on all kernel modules during final link of .ko */
617 if (strstarts(symname, "__s390_indirect_jump_r"))
618 return 1;
619 /* Do not ignore this symbol */
620 return 0;
621}
622
623static void handle_symbol(struct module *mod, struct elf_info *info,
624 const Elf_Sym *sym, const char *symname)
625{
626 switch (sym->st_shndx) {
627 case SHN_COMMON:
628 if (strstarts(symname, "__gnu_lto_")) {
629 /* Should warn here, but modpost runs before the linker */
630 } else
631 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
632 break;
633 case SHN_UNDEF:
634 /* undefined symbol */
635 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
636 ELF_ST_BIND(sym->st_info) != STB_WEAK)
637 break;
638 if (ignore_undef_symbol(info, symname))
639 break;
640 if (info->hdr->e_machine == EM_SPARC ||
641 info->hdr->e_machine == EM_SPARCV9) {
642 /* Ignore register directives. */
643 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
644 break;
645 if (symname[0] == '.') {
646 char *munged = NOFAIL(strdup(symname));
647 munged[0] = '_';
648 munged[1] = toupper(munged[1]);
649 symname = munged;
650 }
651 }
652
653 sym_add_unresolved(symname, mod,
654 ELF_ST_BIND(sym->st_info) == STB_WEAK);
655 break;
656 default:
657 if (strcmp(symname, "init_module") == 0)
658 mod->has_init = true;
659 if (strcmp(symname, "cleanup_module") == 0)
660 mod->has_cleanup = true;
661 break;
662 }
663}
664
665/**
666 * Parse tag=value strings from .modinfo section
667 **/
668static char *next_string(char *string, unsigned long *secsize)
669{
670 /* Skip non-zero chars */
671 while (string[0]) {
672 string++;
673 if ((*secsize)-- <= 1)
674 return NULL;
675 }
676
677 /* Skip any zero padding. */
678 while (!string[0]) {
679 string++;
680 if ((*secsize)-- <= 1)
681 return NULL;
682 }
683 return string;
684}
685
686static char *get_next_modinfo(struct elf_info *info, const char *tag,
687 char *prev)
688{
689 char *p;
690 unsigned int taglen = strlen(tag);
691 char *modinfo = info->modinfo;
692 unsigned long size = info->modinfo_len;
693
694 if (prev) {
695 size -= prev - modinfo;
696 modinfo = next_string(prev, &size);
697 }
698
699 for (p = modinfo; p; p = next_string(p, &size)) {
700 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
701 return p + taglen + 1;
702 }
703 return NULL;
704}
705
706static char *get_modinfo(struct elf_info *info, const char *tag)
707
708{
709 return get_next_modinfo(info, tag, NULL);
710}
711
712static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
713{
714 if (sym)
715 return elf->strtab + sym->st_name;
716 else
717 return "(unknown)";
718}
719
720/*
721 * Check whether the 'string' argument matches one of the 'patterns',
722 * an array of shell wildcard patterns (glob).
723 *
724 * Return true is there is a match.
725 */
726static bool match(const char *string, const char *const patterns[])
727{
728 const char *pattern;
729
730 while ((pattern = *patterns++)) {
731 if (!fnmatch(pattern, string, 0))
732 return true;
733 }
734
735 return false;
736}
737
738/* useful to pass patterns to match() directly */
739#define PATTERNS(...) \
740 ({ \
741 static const char *const patterns[] = {__VA_ARGS__, NULL}; \
742 patterns; \
743 })
744
745/* sections that we do not want to do full section mismatch check on */
746static const char *const section_white_list[] =
747{
748 ".comment*",
749 ".debug*",
750 ".zdebug*", /* Compressed debug sections. */
751 ".GCC.command.line", /* record-gcc-switches */
752 ".mdebug*", /* alpha, score, mips etc. */
753 ".pdr", /* alpha, score, mips etc. */
754 ".stab*",
755 ".note*",
756 ".got*",
757 ".toc*",
758 ".xt.prop", /* xtensa */
759 ".xt.lit", /* xtensa */
760 ".arcextmap*", /* arc */
761 ".gnu.linkonce.arcext*", /* arc : modules */
762 ".cmem*", /* EZchip */
763 ".fmt_slot*", /* EZchip */
764 ".gnu.lto*",
765 ".discard.*",
766 ".llvm.call-graph-profile", /* call graph */
767 NULL
768};
769
770/*
771 * This is used to find sections missing the SHF_ALLOC flag.
772 * The cause of this is often a section specified in assembler
773 * without "ax" / "aw".
774 */
775static void check_section(const char *modname, struct elf_info *elf,
776 Elf_Shdr *sechdr)
777{
778 const char *sec = sech_name(elf, sechdr);
779
780 if (sechdr->sh_type == SHT_PROGBITS &&
781 !(sechdr->sh_flags & SHF_ALLOC) &&
782 !match(sec, section_white_list)) {
783 warn("%s (%s): unexpected non-allocatable section.\n"
784 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
785 "Note that for example <linux/init.h> contains\n"
786 "section definitions for use in .S files.\n\n",
787 modname, sec);
788 }
789}
790
791
792
793#define ALL_INIT_DATA_SECTIONS \
794 ".init.setup", ".init.rodata", ".meminit.rodata", \
795 ".init.data", ".meminit.data"
796
797#define ALL_PCI_INIT_SECTIONS \
798 ".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \
799 ".pci_fixup_enable", ".pci_fixup_resume", \
800 ".pci_fixup_resume_early", ".pci_fixup_suspend"
801
802#define ALL_XXXINIT_SECTIONS ".meminit.*"
803
804#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
805#define ALL_EXIT_SECTIONS ".exit.*"
806
807#define DATA_SECTIONS ".data", ".data.rel"
808#define TEXT_SECTIONS ".text", ".text.*", ".sched.text", \
809 ".kprobes.text", ".cpuidle.text", ".noinstr.text"
810#define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \
811 ".fixup", ".entry.text", ".exception.text", \
812 ".coldtext", ".softirqentry.text"
813
814#define INIT_SECTIONS ".init.*"
815
816#define ALL_TEXT_SECTIONS ".init.text", ".meminit.text", ".exit.text", \
817 TEXT_SECTIONS, OTHER_TEXT_SECTIONS
818
819enum mismatch {
820 TEXTDATA_TO_ANY_INIT_EXIT,
821 XXXINIT_TO_SOME_INIT,
822 ANY_INIT_TO_ANY_EXIT,
823 ANY_EXIT_TO_ANY_INIT,
824 EXTABLE_TO_NON_TEXT,
825};
826
827/**
828 * Describe how to match sections on different criteria:
829 *
830 * @fromsec: Array of sections to be matched.
831 *
832 * @bad_tosec: Relocations applied to a section in @fromsec to a section in
833 * this array is forbidden (black-list). Can be empty.
834 *
835 * @good_tosec: Relocations applied to a section in @fromsec must be
836 * targeting sections in this array (white-list). Can be empty.
837 *
838 * @mismatch: Type of mismatch.
839 */
840struct sectioncheck {
841 const char *fromsec[20];
842 const char *bad_tosec[20];
843 const char *good_tosec[20];
844 enum mismatch mismatch;
845};
846
847static const struct sectioncheck sectioncheck[] = {
848/* Do not reference init/exit code/data from
849 * normal code and data
850 */
851{
852 .fromsec = { TEXT_SECTIONS, DATA_SECTIONS, NULL },
853 .bad_tosec = { ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL },
854 .mismatch = TEXTDATA_TO_ANY_INIT_EXIT,
855},
856/* Do not reference init code/data from meminit code/data */
857{
858 .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
859 .bad_tosec = { INIT_SECTIONS, NULL },
860 .mismatch = XXXINIT_TO_SOME_INIT,
861},
862/* Do not use exit code/data from init code */
863{
864 .fromsec = { ALL_INIT_SECTIONS, NULL },
865 .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
866 .mismatch = ANY_INIT_TO_ANY_EXIT,
867},
868/* Do not use init code/data from exit code */
869{
870 .fromsec = { ALL_EXIT_SECTIONS, NULL },
871 .bad_tosec = { ALL_INIT_SECTIONS, NULL },
872 .mismatch = ANY_EXIT_TO_ANY_INIT,
873},
874{
875 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
876 .bad_tosec = { INIT_SECTIONS, NULL },
877 .mismatch = ANY_INIT_TO_ANY_EXIT,
878},
879{
880 .fromsec = { "__ex_table", NULL },
881 /* If you're adding any new black-listed sections in here, consider
882 * adding a special 'printer' for them in scripts/check_extable.
883 */
884 .bad_tosec = { ".altinstr_replacement", NULL },
885 .good_tosec = {ALL_TEXT_SECTIONS , NULL},
886 .mismatch = EXTABLE_TO_NON_TEXT,
887}
888};
889
890static const struct sectioncheck *section_mismatch(
891 const char *fromsec, const char *tosec)
892{
893 int i;
894
895 /*
896 * The target section could be the SHT_NUL section when we're
897 * handling relocations to un-resolved symbols, trying to match it
898 * doesn't make much sense and causes build failures on parisc
899 * architectures.
900 */
901 if (*tosec == '\0')
902 return NULL;
903
904 for (i = 0; i < ARRAY_SIZE(sectioncheck); i++) {
905 const struct sectioncheck *check = &sectioncheck[i];
906
907 if (match(fromsec, check->fromsec)) {
908 if (check->bad_tosec[0] && match(tosec, check->bad_tosec))
909 return check;
910 if (check->good_tosec[0] && !match(tosec, check->good_tosec))
911 return check;
912 }
913 }
914 return NULL;
915}
916
917/**
918 * Whitelist to allow certain references to pass with no warning.
919 *
920 * Pattern 1:
921 * If a module parameter is declared __initdata and permissions=0
922 * then this is legal despite the warning generated.
923 * We cannot see value of permissions here, so just ignore
924 * this pattern.
925 * The pattern is identified by:
926 * tosec = .init.data
927 * fromsec = .data*
928 * atsym =__param*
929 *
930 * Pattern 1a:
931 * module_param_call() ops can refer to __init set function if permissions=0
932 * The pattern is identified by:
933 * tosec = .init.text
934 * fromsec = .data*
935 * atsym = __param_ops_*
936 *
937 * Pattern 3:
938 * Whitelist all references from .head.text to any init section
939 *
940 * Pattern 4:
941 * Some symbols belong to init section but still it is ok to reference
942 * these from non-init sections as these symbols don't have any memory
943 * allocated for them and symbol address and value are same. So even
944 * if init section is freed, its ok to reference those symbols.
945 * For ex. symbols marking the init section boundaries.
946 * This pattern is identified by
947 * refsymname = __init_begin, _sinittext, _einittext
948 *
949 * Pattern 5:
950 * GCC may optimize static inlines when fed constant arg(s) resulting
951 * in functions like cpumask_empty() -- generating an associated symbol
952 * cpumask_empty.constprop.3 that appears in the audit. If the const that
953 * is passed in comes from __init, like say nmi_ipi_mask, we get a
954 * meaningless section warning. May need to add isra symbols too...
955 * This pattern is identified by
956 * tosec = init section
957 * fromsec = text section
958 * refsymname = *.constprop.*
959 *
960 **/
961static int secref_whitelist(const char *fromsec, const char *fromsym,
962 const char *tosec, const char *tosym)
963{
964 /* Check for pattern 1 */
965 if (match(tosec, PATTERNS(ALL_INIT_DATA_SECTIONS)) &&
966 match(fromsec, PATTERNS(DATA_SECTIONS)) &&
967 strstarts(fromsym, "__param"))
968 return 0;
969
970 /* Check for pattern 1a */
971 if (strcmp(tosec, ".init.text") == 0 &&
972 match(fromsec, PATTERNS(DATA_SECTIONS)) &&
973 strstarts(fromsym, "__param_ops_"))
974 return 0;
975
976 /* symbols in data sections that may refer to any init/exit sections */
977 if (match(fromsec, PATTERNS(DATA_SECTIONS)) &&
978 match(tosec, PATTERNS(ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS)) &&
979 match(fromsym, PATTERNS("*_ops", "*_probe", "*_console")))
980 return 0;
981
982 /*
983 * symbols in data sections must not refer to .exit.*, but there are
984 * quite a few offenders, so hide these unless for W=1 builds until
985 * these are fixed.
986 */
987 if (!extra_warn &&
988 match(fromsec, PATTERNS(DATA_SECTIONS)) &&
989 match(tosec, PATTERNS(ALL_EXIT_SECTIONS)) &&
990 match(fromsym, PATTERNS("*driver")))
991 return 0;
992
993 /* Check for pattern 3 */
994 if (strstarts(fromsec, ".head.text") &&
995 match(tosec, PATTERNS(ALL_INIT_SECTIONS)))
996 return 0;
997
998 /* Check for pattern 4 */
999 if (match(tosym, PATTERNS("__init_begin", "_sinittext", "_einittext")))
1000 return 0;
1001
1002 /* Check for pattern 5 */
1003 if (match(fromsec, PATTERNS(ALL_TEXT_SECTIONS)) &&
1004 match(tosec, PATTERNS(ALL_INIT_SECTIONS)) &&
1005 match(fromsym, PATTERNS("*.constprop.*")))
1006 return 0;
1007
1008 return 1;
1009}
1010
1011static Elf_Sym *find_fromsym(struct elf_info *elf, Elf_Addr addr,
1012 unsigned int secndx)
1013{
1014 return symsearch_find_nearest(elf, addr, secndx, false, ~0);
1015}
1016
1017static Elf_Sym *find_tosym(struct elf_info *elf, Elf_Addr addr, Elf_Sym *sym)
1018{
1019 /* If the supplied symbol has a valid name, return it */
1020 if (is_valid_name(elf, sym))
1021 return sym;
1022
1023 /*
1024 * Strive to find a better symbol name, but the resulting name may not
1025 * match the symbol referenced in the original code.
1026 */
1027 return symsearch_find_nearest(elf, addr, get_secindex(elf, sym),
1028 true, 20);
1029}
1030
1031static bool is_executable_section(struct elf_info *elf, unsigned int secndx)
1032{
1033 if (secndx >= elf->num_sections)
1034 return false;
1035
1036 return (elf->sechdrs[secndx].sh_flags & SHF_EXECINSTR) != 0;
1037}
1038
1039static void default_mismatch_handler(const char *modname, struct elf_info *elf,
1040 const struct sectioncheck* const mismatch,
1041 Elf_Sym *tsym,
1042 unsigned int fsecndx, const char *fromsec, Elf_Addr faddr,
1043 const char *tosec, Elf_Addr taddr)
1044{
1045 Elf_Sym *from;
1046 const char *tosym;
1047 const char *fromsym;
1048
1049 from = find_fromsym(elf, faddr, fsecndx);
1050 fromsym = sym_name(elf, from);
1051
1052 tsym = find_tosym(elf, taddr, tsym);
1053 tosym = sym_name(elf, tsym);
1054
1055 /* check whitelist - we may ignore it */
1056 if (!secref_whitelist(fromsec, fromsym, tosec, tosym))
1057 return;
1058
1059 sec_mismatch_count++;
1060
1061 warn("%s: section mismatch in reference: %s+0x%x (section: %s) -> %s (section: %s)\n",
1062 modname, fromsym, (unsigned int)(faddr - from->st_value), fromsec, tosym, tosec);
1063
1064 if (mismatch->mismatch == EXTABLE_TO_NON_TEXT) {
1065 if (match(tosec, mismatch->bad_tosec))
1066 fatal("The relocation at %s+0x%lx references\n"
1067 "section \"%s\" which is black-listed.\n"
1068 "Something is seriously wrong and should be fixed.\n"
1069 "You might get more information about where this is\n"
1070 "coming from by using scripts/check_extable.sh %s\n",
1071 fromsec, (long)faddr, tosec, modname);
1072 else if (is_executable_section(elf, get_secindex(elf, tsym)))
1073 warn("The relocation at %s+0x%lx references\n"
1074 "section \"%s\" which is not in the list of\n"
1075 "authorized sections. If you're adding a new section\n"
1076 "and/or if this reference is valid, add \"%s\" to the\n"
1077 "list of authorized sections to jump to on fault.\n"
1078 "This can be achieved by adding \"%s\" to\n"
1079 "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n",
1080 fromsec, (long)faddr, tosec, tosec, tosec);
1081 else
1082 error("%s+0x%lx references non-executable section '%s'\n",
1083 fromsec, (long)faddr, tosec);
1084 }
1085}
1086
1087static void check_export_symbol(struct module *mod, struct elf_info *elf,
1088 Elf_Addr faddr, const char *secname,
1089 Elf_Sym *sym)
1090{
1091 static const char *prefix = "__export_symbol_";
1092 const char *label_name, *name, *data;
1093 Elf_Sym *label;
1094 struct symbol *s;
1095 bool is_gpl;
1096
1097 label = find_fromsym(elf, faddr, elf->export_symbol_secndx);
1098 label_name = sym_name(elf, label);
1099
1100 if (!strstarts(label_name, prefix)) {
1101 error("%s: .export_symbol section contains strange symbol '%s'\n",
1102 mod->name, label_name);
1103 return;
1104 }
1105
1106 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
1107 ELF_ST_BIND(sym->st_info) != STB_WEAK) {
1108 error("%s: local symbol '%s' was exported\n", mod->name,
1109 label_name + strlen(prefix));
1110 return;
1111 }
1112
1113 name = sym_name(elf, sym);
1114 if (strcmp(label_name + strlen(prefix), name)) {
1115 error("%s: .export_symbol section references '%s', but it does not seem to be an export symbol\n",
1116 mod->name, name);
1117 return;
1118 }
1119
1120 data = sym_get_data(elf, label); /* license */
1121 if (!strcmp(data, "GPL")) {
1122 is_gpl = true;
1123 } else if (!strcmp(data, "")) {
1124 is_gpl = false;
1125 } else {
1126 error("%s: unknown license '%s' was specified for '%s'\n",
1127 mod->name, data, name);
1128 return;
1129 }
1130
1131 data += strlen(data) + 1; /* namespace */
1132 s = sym_add_exported(name, mod, is_gpl, data);
1133
1134 /*
1135 * We need to be aware whether we are exporting a function or
1136 * a data on some architectures.
1137 */
1138 s->is_func = (ELF_ST_TYPE(sym->st_info) == STT_FUNC);
1139
1140 /*
1141 * For parisc64, symbols prefixed $$ from the library have the symbol type
1142 * STT_LOPROC. They should be handled as functions too.
1143 */
1144 if (elf->hdr->e_ident[EI_CLASS] == ELFCLASS64 &&
1145 elf->hdr->e_machine == EM_PARISC &&
1146 ELF_ST_TYPE(sym->st_info) == STT_LOPROC)
1147 s->is_func = true;
1148
1149 if (match(secname, PATTERNS(ALL_INIT_SECTIONS)))
1150 warn("%s: %s: EXPORT_SYMBOL used for init symbol. Remove __init or EXPORT_SYMBOL.\n",
1151 mod->name, name);
1152 else if (match(secname, PATTERNS(ALL_EXIT_SECTIONS)))
1153 warn("%s: %s: EXPORT_SYMBOL used for exit symbol. Remove __exit or EXPORT_SYMBOL.\n",
1154 mod->name, name);
1155}
1156
1157static void check_section_mismatch(struct module *mod, struct elf_info *elf,
1158 Elf_Sym *sym,
1159 unsigned int fsecndx, const char *fromsec,
1160 Elf_Addr faddr, Elf_Addr taddr)
1161{
1162 const char *tosec = sec_name(elf, get_secindex(elf, sym));
1163 const struct sectioncheck *mismatch;
1164
1165 if (module_enabled && elf->export_symbol_secndx == fsecndx) {
1166 check_export_symbol(mod, elf, faddr, tosec, sym);
1167 return;
1168 }
1169
1170 mismatch = section_mismatch(fromsec, tosec);
1171 if (!mismatch)
1172 return;
1173
1174 default_mismatch_handler(mod->name, elf, mismatch, sym,
1175 fsecndx, fromsec, faddr,
1176 tosec, taddr);
1177}
1178
1179static Elf_Addr addend_386_rel(uint32_t *location, unsigned int r_type)
1180{
1181 switch (r_type) {
1182 case R_386_32:
1183 return TO_NATIVE(*location);
1184 case R_386_PC32:
1185 return TO_NATIVE(*location) + 4;
1186 }
1187
1188 return (Elf_Addr)(-1);
1189}
1190
1191#ifndef R_ARM_CALL
1192#define R_ARM_CALL 28
1193#endif
1194#ifndef R_ARM_JUMP24
1195#define R_ARM_JUMP24 29
1196#endif
1197
1198#ifndef R_ARM_THM_CALL
1199#define R_ARM_THM_CALL 10
1200#endif
1201#ifndef R_ARM_THM_JUMP24
1202#define R_ARM_THM_JUMP24 30
1203#endif
1204
1205#ifndef R_ARM_MOVW_ABS_NC
1206#define R_ARM_MOVW_ABS_NC 43
1207#endif
1208
1209#ifndef R_ARM_MOVT_ABS
1210#define R_ARM_MOVT_ABS 44
1211#endif
1212
1213#ifndef R_ARM_THM_MOVW_ABS_NC
1214#define R_ARM_THM_MOVW_ABS_NC 47
1215#endif
1216
1217#ifndef R_ARM_THM_MOVT_ABS
1218#define R_ARM_THM_MOVT_ABS 48
1219#endif
1220
1221#ifndef R_ARM_THM_JUMP19
1222#define R_ARM_THM_JUMP19 51
1223#endif
1224
1225static int32_t sign_extend32(int32_t value, int index)
1226{
1227 uint8_t shift = 31 - index;
1228
1229 return (int32_t)(value << shift) >> shift;
1230}
1231
1232static Elf_Addr addend_arm_rel(void *loc, Elf_Sym *sym, unsigned int r_type)
1233{
1234 uint32_t inst, upper, lower, sign, j1, j2;
1235 int32_t offset;
1236
1237 switch (r_type) {
1238 case R_ARM_ABS32:
1239 case R_ARM_REL32:
1240 inst = TO_NATIVE(*(uint32_t *)loc);
1241 return inst + sym->st_value;
1242 case R_ARM_MOVW_ABS_NC:
1243 case R_ARM_MOVT_ABS:
1244 inst = TO_NATIVE(*(uint32_t *)loc);
1245 offset = sign_extend32(((inst & 0xf0000) >> 4) | (inst & 0xfff),
1246 15);
1247 return offset + sym->st_value;
1248 case R_ARM_PC24:
1249 case R_ARM_CALL:
1250 case R_ARM_JUMP24:
1251 inst = TO_NATIVE(*(uint32_t *)loc);
1252 offset = sign_extend32((inst & 0x00ffffff) << 2, 25);
1253 return offset + sym->st_value + 8;
1254 case R_ARM_THM_MOVW_ABS_NC:
1255 case R_ARM_THM_MOVT_ABS:
1256 upper = TO_NATIVE(*(uint16_t *)loc);
1257 lower = TO_NATIVE(*((uint16_t *)loc + 1));
1258 offset = sign_extend32(((upper & 0x000f) << 12) |
1259 ((upper & 0x0400) << 1) |
1260 ((lower & 0x7000) >> 4) |
1261 (lower & 0x00ff),
1262 15);
1263 return offset + sym->st_value;
1264 case R_ARM_THM_JUMP19:
1265 /*
1266 * Encoding T3:
1267 * S = upper[10]
1268 * imm6 = upper[5:0]
1269 * J1 = lower[13]
1270 * J2 = lower[11]
1271 * imm11 = lower[10:0]
1272 * imm32 = SignExtend(S:J2:J1:imm6:imm11:'0')
1273 */
1274 upper = TO_NATIVE(*(uint16_t *)loc);
1275 lower = TO_NATIVE(*((uint16_t *)loc + 1));
1276
1277 sign = (upper >> 10) & 1;
1278 j1 = (lower >> 13) & 1;
1279 j2 = (lower >> 11) & 1;
1280 offset = sign_extend32((sign << 20) | (j2 << 19) | (j1 << 18) |
1281 ((upper & 0x03f) << 12) |
1282 ((lower & 0x07ff) << 1),
1283 20);
1284 return offset + sym->st_value + 4;
1285 case R_ARM_THM_CALL:
1286 case R_ARM_THM_JUMP24:
1287 /*
1288 * Encoding T4:
1289 * S = upper[10]
1290 * imm10 = upper[9:0]
1291 * J1 = lower[13]
1292 * J2 = lower[11]
1293 * imm11 = lower[10:0]
1294 * I1 = NOT(J1 XOR S)
1295 * I2 = NOT(J2 XOR S)
1296 * imm32 = SignExtend(S:I1:I2:imm10:imm11:'0')
1297 */
1298 upper = TO_NATIVE(*(uint16_t *)loc);
1299 lower = TO_NATIVE(*((uint16_t *)loc + 1));
1300
1301 sign = (upper >> 10) & 1;
1302 j1 = (lower >> 13) & 1;
1303 j2 = (lower >> 11) & 1;
1304 offset = sign_extend32((sign << 24) |
1305 ((~(j1 ^ sign) & 1) << 23) |
1306 ((~(j2 ^ sign) & 1) << 22) |
1307 ((upper & 0x03ff) << 12) |
1308 ((lower & 0x07ff) << 1),
1309 24);
1310 return offset + sym->st_value + 4;
1311 }
1312
1313 return (Elf_Addr)(-1);
1314}
1315
1316static Elf_Addr addend_mips_rel(uint32_t *location, unsigned int r_type)
1317{
1318 uint32_t inst;
1319
1320 inst = TO_NATIVE(*location);
1321 switch (r_type) {
1322 case R_MIPS_LO16:
1323 return inst & 0xffff;
1324 case R_MIPS_26:
1325 return (inst & 0x03ffffff) << 2;
1326 case R_MIPS_32:
1327 return inst;
1328 }
1329 return (Elf_Addr)(-1);
1330}
1331
1332#ifndef EM_RISCV
1333#define EM_RISCV 243
1334#endif
1335
1336#ifndef R_RISCV_SUB32
1337#define R_RISCV_SUB32 39
1338#endif
1339
1340#ifndef EM_LOONGARCH
1341#define EM_LOONGARCH 258
1342#endif
1343
1344#ifndef R_LARCH_SUB32
1345#define R_LARCH_SUB32 55
1346#endif
1347
1348#ifndef R_LARCH_RELAX
1349#define R_LARCH_RELAX 100
1350#endif
1351
1352#ifndef R_LARCH_ALIGN
1353#define R_LARCH_ALIGN 102
1354#endif
1355
1356static void get_rel_type_and_sym(struct elf_info *elf, uint64_t r_info,
1357 unsigned int *r_type, unsigned int *r_sym)
1358{
1359 typedef struct {
1360 Elf64_Word r_sym; /* Symbol index */
1361 unsigned char r_ssym; /* Special symbol for 2nd relocation */
1362 unsigned char r_type3; /* 3rd relocation type */
1363 unsigned char r_type2; /* 2nd relocation type */
1364 unsigned char r_type; /* 1st relocation type */
1365 } Elf64_Mips_R_Info;
1366
1367 bool is_64bit = (elf->hdr->e_ident[EI_CLASS] == ELFCLASS64);
1368
1369 if (elf->hdr->e_machine == EM_MIPS && is_64bit) {
1370 Elf64_Mips_R_Info *mips64_r_info = (void *)&r_info;
1371
1372 *r_type = mips64_r_info->r_type;
1373 *r_sym = TO_NATIVE(mips64_r_info->r_sym);
1374 return;
1375 }
1376
1377 if (is_64bit)
1378 r_info = TO_NATIVE((Elf64_Xword)r_info);
1379 else
1380 r_info = TO_NATIVE((Elf32_Word)r_info);
1381
1382 *r_type = ELF_R_TYPE(r_info);
1383 *r_sym = ELF_R_SYM(r_info);
1384}
1385
1386static void section_rela(struct module *mod, struct elf_info *elf,
1387 unsigned int fsecndx, const char *fromsec,
1388 const Elf_Rela *start, const Elf_Rela *stop)
1389{
1390 const Elf_Rela *rela;
1391
1392 for (rela = start; rela < stop; rela++) {
1393 Elf_Sym *tsym;
1394 Elf_Addr taddr, r_offset;
1395 unsigned int r_type, r_sym;
1396
1397 r_offset = TO_NATIVE(rela->r_offset);
1398 get_rel_type_and_sym(elf, rela->r_info, &r_type, &r_sym);
1399
1400 tsym = elf->symtab_start + r_sym;
1401 taddr = tsym->st_value + TO_NATIVE(rela->r_addend);
1402
1403 switch (elf->hdr->e_machine) {
1404 case EM_RISCV:
1405 if (!strcmp("__ex_table", fromsec) &&
1406 r_type == R_RISCV_SUB32)
1407 continue;
1408 break;
1409 case EM_LOONGARCH:
1410 switch (r_type) {
1411 case R_LARCH_SUB32:
1412 if (!strcmp("__ex_table", fromsec))
1413 continue;
1414 break;
1415 case R_LARCH_RELAX:
1416 case R_LARCH_ALIGN:
1417 /* These relocs do not refer to symbols */
1418 continue;
1419 }
1420 break;
1421 }
1422
1423 check_section_mismatch(mod, elf, tsym,
1424 fsecndx, fromsec, r_offset, taddr);
1425 }
1426}
1427
1428static void section_rel(struct module *mod, struct elf_info *elf,
1429 unsigned int fsecndx, const char *fromsec,
1430 const Elf_Rel *start, const Elf_Rel *stop)
1431{
1432 const Elf_Rel *rel;
1433
1434 for (rel = start; rel < stop; rel++) {
1435 Elf_Sym *tsym;
1436 Elf_Addr taddr, r_offset;
1437 unsigned int r_type, r_sym;
1438 void *loc;
1439
1440 r_offset = TO_NATIVE(rel->r_offset);
1441 get_rel_type_and_sym(elf, rel->r_info, &r_type, &r_sym);
1442
1443 loc = sym_get_data_by_offset(elf, fsecndx, r_offset);
1444 tsym = elf->symtab_start + r_sym;
1445
1446 switch (elf->hdr->e_machine) {
1447 case EM_386:
1448 taddr = addend_386_rel(loc, r_type);
1449 break;
1450 case EM_ARM:
1451 taddr = addend_arm_rel(loc, tsym, r_type);
1452 break;
1453 case EM_MIPS:
1454 taddr = addend_mips_rel(loc, r_type);
1455 break;
1456 default:
1457 fatal("Please add code to calculate addend for this architecture\n");
1458 }
1459
1460 check_section_mismatch(mod, elf, tsym,
1461 fsecndx, fromsec, r_offset, taddr);
1462 }
1463}
1464
1465/**
1466 * A module includes a number of sections that are discarded
1467 * either when loaded or when used as built-in.
1468 * For loaded modules all functions marked __init and all data
1469 * marked __initdata will be discarded when the module has been initialized.
1470 * Likewise for modules used built-in the sections marked __exit
1471 * are discarded because __exit marked function are supposed to be called
1472 * only when a module is unloaded which never happens for built-in modules.
1473 * The check_sec_ref() function traverses all relocation records
1474 * to find all references to a section that reference a section that will
1475 * be discarded and warns about it.
1476 **/
1477static void check_sec_ref(struct module *mod, struct elf_info *elf)
1478{
1479 int i;
1480
1481 /* Walk through all sections */
1482 for (i = 0; i < elf->num_sections; i++) {
1483 Elf_Shdr *sechdr = &elf->sechdrs[i];
1484
1485 check_section(mod->name, elf, sechdr);
1486 /* We want to process only relocation sections and not .init */
1487 if (sechdr->sh_type == SHT_REL || sechdr->sh_type == SHT_RELA) {
1488 /* section to which the relocation applies */
1489 unsigned int secndx = sechdr->sh_info;
1490 const char *secname = sec_name(elf, secndx);
1491 const void *start, *stop;
1492
1493 /* If the section is known good, skip it */
1494 if (match(secname, section_white_list))
1495 continue;
1496
1497 start = sym_get_data_by_offset(elf, i, 0);
1498 stop = start + sechdr->sh_size;
1499
1500 if (sechdr->sh_type == SHT_RELA)
1501 section_rela(mod, elf, secndx, secname,
1502 start, stop);
1503 else
1504 section_rel(mod, elf, secndx, secname,
1505 start, stop);
1506 }
1507 }
1508}
1509
1510static char *remove_dot(char *s)
1511{
1512 size_t n = strcspn(s, ".");
1513
1514 if (n && s[n]) {
1515 size_t m = strspn(s + n + 1, "0123456789");
1516 if (m && (s[n + m + 1] == '.' || s[n + m + 1] == 0))
1517 s[n] = 0;
1518 }
1519 return s;
1520}
1521
1522/*
1523 * The CRCs are recorded in .*.cmd files in the form of:
1524 * #SYMVER <name> <crc>
1525 */
1526static void extract_crcs_for_object(const char *object, struct module *mod)
1527{
1528 char cmd_file[PATH_MAX];
1529 char *buf, *p;
1530 const char *base;
1531 int dirlen, ret;
1532
1533 base = strrchr(object, '/');
1534 if (base) {
1535 base++;
1536 dirlen = base - object;
1537 } else {
1538 dirlen = 0;
1539 base = object;
1540 }
1541
1542 ret = snprintf(cmd_file, sizeof(cmd_file), "%.*s.%s.cmd",
1543 dirlen, object, base);
1544 if (ret >= sizeof(cmd_file)) {
1545 error("%s: too long path was truncated\n", cmd_file);
1546 return;
1547 }
1548
1549 buf = read_text_file(cmd_file);
1550 p = buf;
1551
1552 while ((p = strstr(p, "\n#SYMVER "))) {
1553 char *name;
1554 size_t namelen;
1555 unsigned int crc;
1556 struct symbol *sym;
1557
1558 name = p + strlen("\n#SYMVER ");
1559
1560 p = strchr(name, ' ');
1561 if (!p)
1562 break;
1563
1564 namelen = p - name;
1565 p++;
1566
1567 if (!isdigit(*p))
1568 continue; /* skip this line */
1569
1570 crc = strtoul(p, &p, 0);
1571 if (*p != '\n')
1572 continue; /* skip this line */
1573
1574 name[namelen] = '\0';
1575
1576 /*
1577 * sym_find_with_module() may return NULL here.
1578 * It typically occurs when CONFIG_TRIM_UNUSED_KSYMS=y.
1579 * Since commit e1327a127703, genksyms calculates CRCs of all
1580 * symbols, including trimmed ones. Ignore orphan CRCs.
1581 */
1582 sym = sym_find_with_module(name, mod);
1583 if (sym)
1584 sym_set_crc(sym, crc);
1585 }
1586
1587 free(buf);
1588}
1589
1590/*
1591 * The symbol versions (CRC) are recorded in the .*.cmd files.
1592 * Parse them to retrieve CRCs for the current module.
1593 */
1594static void mod_set_crcs(struct module *mod)
1595{
1596 char objlist[PATH_MAX];
1597 char *buf, *p, *obj;
1598 int ret;
1599
1600 if (mod->is_vmlinux) {
1601 strcpy(objlist, ".vmlinux.objs");
1602 } else {
1603 /* objects for a module are listed in the *.mod file. */
1604 ret = snprintf(objlist, sizeof(objlist), "%s.mod", mod->name);
1605 if (ret >= sizeof(objlist)) {
1606 error("%s: too long path was truncated\n", objlist);
1607 return;
1608 }
1609 }
1610
1611 buf = read_text_file(objlist);
1612 p = buf;
1613
1614 while ((obj = strsep(&p, "\n")) && obj[0])
1615 extract_crcs_for_object(obj, mod);
1616
1617 free(buf);
1618}
1619
1620static void read_symbols(const char *modname)
1621{
1622 const char *symname;
1623 char *version;
1624 char *license;
1625 char *namespace;
1626 struct module *mod;
1627 struct elf_info info = { };
1628 Elf_Sym *sym;
1629
1630 if (!parse_elf(&info, modname))
1631 return;
1632
1633 if (!strends(modname, ".o")) {
1634 error("%s: filename must be suffixed with .o\n", modname);
1635 return;
1636 }
1637
1638 /* strip trailing .o */
1639 mod = new_module(modname, strlen(modname) - strlen(".o"));
1640
1641 if (!mod->is_vmlinux) {
1642 license = get_modinfo(&info, "license");
1643 if (!license)
1644 error("missing MODULE_LICENSE() in %s\n", modname);
1645 while (license) {
1646 if (!license_is_gpl_compatible(license)) {
1647 mod->is_gpl_compatible = false;
1648 break;
1649 }
1650 license = get_next_modinfo(&info, "license", license);
1651 }
1652
1653 namespace = get_modinfo(&info, "import_ns");
1654 while (namespace) {
1655 add_namespace(&mod->imported_namespaces, namespace);
1656 namespace = get_next_modinfo(&info, "import_ns",
1657 namespace);
1658 }
1659 }
1660
1661 if (extra_warn && !get_modinfo(&info, "description"))
1662 warn("missing MODULE_DESCRIPTION() in %s\n", modname);
1663 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
1664 symname = remove_dot(info.strtab + sym->st_name);
1665
1666 handle_symbol(mod, &info, sym, symname);
1667 handle_moddevtable(mod, &info, sym, symname);
1668 }
1669
1670 check_sec_ref(mod, &info);
1671
1672 if (!mod->is_vmlinux) {
1673 version = get_modinfo(&info, "version");
1674 if (version || all_versions)
1675 get_src_version(mod->name, mod->srcversion,
1676 sizeof(mod->srcversion) - 1);
1677 }
1678
1679 parse_elf_finish(&info);
1680
1681 if (modversions) {
1682 /*
1683 * Our trick to get versioning for module struct etc. - it's
1684 * never passed as an argument to an exported function, so
1685 * the automatic versioning doesn't pick it up, but it's really
1686 * important anyhow.
1687 */
1688 sym_add_unresolved("module_layout", mod, false);
1689
1690 mod_set_crcs(mod);
1691 }
1692}
1693
1694static void read_symbols_from_files(const char *filename)
1695{
1696 FILE *in = stdin;
1697 char fname[PATH_MAX];
1698
1699 in = fopen(filename, "r");
1700 if (!in)
1701 fatal("Can't open filenames file %s: %m", filename);
1702
1703 while (fgets(fname, PATH_MAX, in) != NULL) {
1704 if (strends(fname, "\n"))
1705 fname[strlen(fname)-1] = '\0';
1706 read_symbols(fname);
1707 }
1708
1709 fclose(in);
1710}
1711
1712#define SZ 500
1713
1714/* We first write the generated file into memory using the
1715 * following helper, then compare to the file on disk and
1716 * only update the later if anything changed */
1717
1718void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
1719 const char *fmt, ...)
1720{
1721 char tmp[SZ];
1722 int len;
1723 va_list ap;
1724
1725 va_start(ap, fmt);
1726 len = vsnprintf(tmp, SZ, fmt, ap);
1727 buf_write(buf, tmp, len);
1728 va_end(ap);
1729}
1730
1731void buf_write(struct buffer *buf, const char *s, int len)
1732{
1733 if (buf->size - buf->pos < len) {
1734 buf->size += len + SZ;
1735 buf->p = NOFAIL(realloc(buf->p, buf->size));
1736 }
1737 strncpy(buf->p + buf->pos, s, len);
1738 buf->pos += len;
1739}
1740
1741static void check_exports(struct module *mod)
1742{
1743 struct symbol *s, *exp;
1744
1745 list_for_each_entry(s, &mod->unresolved_symbols, list) {
1746 const char *basename;
1747 exp = find_symbol(s->name);
1748 if (!exp) {
1749 if (!s->weak && nr_unresolved++ < MAX_UNRESOLVED_REPORTS)
1750 modpost_log(warn_unresolved ? LOG_WARN : LOG_ERROR,
1751 "\"%s\" [%s.ko] undefined!\n",
1752 s->name, mod->name);
1753 continue;
1754 }
1755 if (exp->module == mod) {
1756 error("\"%s\" [%s.ko] was exported without definition\n",
1757 s->name, mod->name);
1758 continue;
1759 }
1760
1761 exp->used = true;
1762 s->module = exp->module;
1763 s->crc_valid = exp->crc_valid;
1764 s->crc = exp->crc;
1765
1766 basename = strrchr(mod->name, '/');
1767 if (basename)
1768 basename++;
1769 else
1770 basename = mod->name;
1771
1772 if (!contains_namespace(&mod->imported_namespaces, exp->namespace)) {
1773 modpost_log(allow_missing_ns_imports ? LOG_WARN : LOG_ERROR,
1774 "module %s uses symbol %s from namespace %s, but does not import it.\n",
1775 basename, exp->name, exp->namespace);
1776 add_namespace(&mod->missing_namespaces, exp->namespace);
1777 }
1778
1779 if (!mod->is_gpl_compatible && exp->is_gpl_only)
1780 error("GPL-incompatible module %s.ko uses GPL-only symbol '%s'\n",
1781 basename, exp->name);
1782 }
1783}
1784
1785static void handle_white_list_exports(const char *white_list)
1786{
1787 char *buf, *p, *name;
1788
1789 buf = read_text_file(white_list);
1790 p = buf;
1791
1792 while ((name = strsep(&p, "\n"))) {
1793 struct symbol *sym = find_symbol(name);
1794
1795 if (sym)
1796 sym->used = true;
1797 }
1798
1799 free(buf);
1800}
1801
1802static void check_modname_len(struct module *mod)
1803{
1804 const char *mod_name;
1805
1806 mod_name = strrchr(mod->name, '/');
1807 if (mod_name == NULL)
1808 mod_name = mod->name;
1809 else
1810 mod_name++;
1811 if (strlen(mod_name) >= MODULE_NAME_LEN)
1812 error("module name is too long [%s.ko]\n", mod->name);
1813}
1814
1815/**
1816 * Header for the generated file
1817 **/
1818static void add_header(struct buffer *b, struct module *mod)
1819{
1820 buf_printf(b, "#include <linux/module.h>\n");
1821 /*
1822 * Include build-salt.h after module.h in order to
1823 * inherit the definitions.
1824 */
1825 buf_printf(b, "#define INCLUDE_VERMAGIC\n");
1826 buf_printf(b, "#include <linux/build-salt.h>\n");
1827 buf_printf(b, "#include <linux/elfnote-lto.h>\n");
1828 buf_printf(b, "#include <linux/export-internal.h>\n");
1829 buf_printf(b, "#include <linux/vermagic.h>\n");
1830 buf_printf(b, "#include <linux/compiler.h>\n");
1831 buf_printf(b, "\n");
1832 buf_printf(b, "#ifdef CONFIG_UNWINDER_ORC\n");
1833 buf_printf(b, "#include <asm/orc_header.h>\n");
1834 buf_printf(b, "ORC_HEADER;\n");
1835 buf_printf(b, "#endif\n");
1836 buf_printf(b, "\n");
1837 buf_printf(b, "BUILD_SALT;\n");
1838 buf_printf(b, "BUILD_LTO_INFO;\n");
1839 buf_printf(b, "\n");
1840 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1841 buf_printf(b, "MODULE_INFO(name, KBUILD_MODNAME);\n");
1842 buf_printf(b, "\n");
1843 buf_printf(b, "__visible struct module __this_module\n");
1844 buf_printf(b, "__section(\".gnu.linkonce.this_module\") = {\n");
1845 buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
1846 if (mod->has_init)
1847 buf_printf(b, "\t.init = init_module,\n");
1848 if (mod->has_cleanup)
1849 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
1850 "\t.exit = cleanup_module,\n"
1851 "#endif\n");
1852 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
1853 buf_printf(b, "};\n");
1854
1855 if (!external_module)
1856 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
1857
1858 buf_printf(b,
1859 "\n"
1860 "#ifdef CONFIG_RETPOLINE\n"
1861 "MODULE_INFO(retpoline, \"Y\");\n"
1862 "#endif\n");
1863
1864 if (strstarts(mod->name, "drivers/staging"))
1865 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
1866
1867 if (strstarts(mod->name, "tools/testing"))
1868 buf_printf(b, "\nMODULE_INFO(test, \"Y\");\n");
1869}
1870
1871static void add_exported_symbols(struct buffer *buf, struct module *mod)
1872{
1873 struct symbol *sym;
1874
1875 /* generate struct for exported symbols */
1876 buf_printf(buf, "\n");
1877 list_for_each_entry(sym, &mod->exported_symbols, list) {
1878 if (trim_unused_exports && !sym->used)
1879 continue;
1880
1881 buf_printf(buf, "KSYMTAB_%s(%s, \"%s\", \"%s\");\n",
1882 sym->is_func ? "FUNC" : "DATA", sym->name,
1883 sym->is_gpl_only ? "_gpl" : "", sym->namespace);
1884 }
1885
1886 if (!modversions)
1887 return;
1888
1889 /* record CRCs for exported symbols */
1890 buf_printf(buf, "\n");
1891 list_for_each_entry(sym, &mod->exported_symbols, list) {
1892 if (trim_unused_exports && !sym->used)
1893 continue;
1894
1895 if (!sym->crc_valid)
1896 warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n"
1897 "Is \"%s\" prototyped in <asm/asm-prototypes.h>?\n",
1898 sym->name, mod->name, mod->is_vmlinux ? "" : ".ko",
1899 sym->name);
1900
1901 buf_printf(buf, "SYMBOL_CRC(%s, 0x%08x, \"%s\");\n",
1902 sym->name, sym->crc, sym->is_gpl_only ? "_gpl" : "");
1903 }
1904}
1905
1906/**
1907 * Record CRCs for unresolved symbols
1908 **/
1909static void add_versions(struct buffer *b, struct module *mod)
1910{
1911 struct symbol *s;
1912
1913 if (!modversions)
1914 return;
1915
1916 buf_printf(b, "\n");
1917 buf_printf(b, "static const struct modversion_info ____versions[]\n");
1918 buf_printf(b, "__used __section(\"__versions\") = {\n");
1919
1920 list_for_each_entry(s, &mod->unresolved_symbols, list) {
1921 if (!s->module)
1922 continue;
1923 if (!s->crc_valid) {
1924 warn("\"%s\" [%s.ko] has no CRC!\n",
1925 s->name, mod->name);
1926 continue;
1927 }
1928 if (strlen(s->name) >= MODULE_NAME_LEN) {
1929 error("too long symbol \"%s\" [%s.ko]\n",
1930 s->name, mod->name);
1931 break;
1932 }
1933 buf_printf(b, "\t{ %#8x, \"%s\" },\n",
1934 s->crc, s->name);
1935 }
1936
1937 buf_printf(b, "};\n");
1938}
1939
1940static void add_depends(struct buffer *b, struct module *mod)
1941{
1942 struct symbol *s;
1943 int first = 1;
1944
1945 /* Clear ->seen flag of modules that own symbols needed by this. */
1946 list_for_each_entry(s, &mod->unresolved_symbols, list) {
1947 if (s->module)
1948 s->module->seen = s->module->is_vmlinux;
1949 }
1950
1951 buf_printf(b, "\n");
1952 buf_printf(b, "MODULE_INFO(depends, \"");
1953 list_for_each_entry(s, &mod->unresolved_symbols, list) {
1954 const char *p;
1955 if (!s->module)
1956 continue;
1957
1958 if (s->module->seen)
1959 continue;
1960
1961 s->module->seen = true;
1962 p = strrchr(s->module->name, '/');
1963 if (p)
1964 p++;
1965 else
1966 p = s->module->name;
1967 buf_printf(b, "%s%s", first ? "" : ",", p);
1968 first = 0;
1969 }
1970 buf_printf(b, "\");\n");
1971}
1972
1973static void add_srcversion(struct buffer *b, struct module *mod)
1974{
1975 if (mod->srcversion[0]) {
1976 buf_printf(b, "\n");
1977 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
1978 mod->srcversion);
1979 }
1980}
1981
1982static void write_buf(struct buffer *b, const char *fname)
1983{
1984 FILE *file;
1985
1986 if (error_occurred)
1987 return;
1988
1989 file = fopen(fname, "w");
1990 if (!file) {
1991 perror(fname);
1992 exit(1);
1993 }
1994 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
1995 perror(fname);
1996 exit(1);
1997 }
1998 if (fclose(file) != 0) {
1999 perror(fname);
2000 exit(1);
2001 }
2002}
2003
2004static void write_if_changed(struct buffer *b, const char *fname)
2005{
2006 char *tmp;
2007 FILE *file;
2008 struct stat st;
2009
2010 file = fopen(fname, "r");
2011 if (!file)
2012 goto write;
2013
2014 if (fstat(fileno(file), &st) < 0)
2015 goto close_write;
2016
2017 if (st.st_size != b->pos)
2018 goto close_write;
2019
2020 tmp = NOFAIL(malloc(b->pos));
2021 if (fread(tmp, 1, b->pos, file) != b->pos)
2022 goto free_write;
2023
2024 if (memcmp(tmp, b->p, b->pos) != 0)
2025 goto free_write;
2026
2027 free(tmp);
2028 fclose(file);
2029 return;
2030
2031 free_write:
2032 free(tmp);
2033 close_write:
2034 fclose(file);
2035 write:
2036 write_buf(b, fname);
2037}
2038
2039static void write_vmlinux_export_c_file(struct module *mod)
2040{
2041 struct buffer buf = { };
2042
2043 buf_printf(&buf,
2044 "#include <linux/export-internal.h>\n");
2045
2046 add_exported_symbols(&buf, mod);
2047 write_if_changed(&buf, ".vmlinux.export.c");
2048 free(buf.p);
2049}
2050
2051/* do sanity checks, and generate *.mod.c file */
2052static void write_mod_c_file(struct module *mod)
2053{
2054 struct buffer buf = { };
2055 char fname[PATH_MAX];
2056 int ret;
2057
2058 add_header(&buf, mod);
2059 add_exported_symbols(&buf, mod);
2060 add_versions(&buf, mod);
2061 add_depends(&buf, mod);
2062 add_moddevtable(&buf, mod);
2063 add_srcversion(&buf, mod);
2064
2065 ret = snprintf(fname, sizeof(fname), "%s.mod.c", mod->name);
2066 if (ret >= sizeof(fname)) {
2067 error("%s: too long path was truncated\n", fname);
2068 goto free;
2069 }
2070
2071 write_if_changed(&buf, fname);
2072
2073free:
2074 free(buf.p);
2075}
2076
2077/* parse Module.symvers file. line format:
2078 * 0x12345678<tab>symbol<tab>module<tab>export<tab>namespace
2079 **/
2080static void read_dump(const char *fname)
2081{
2082 char *buf, *pos, *line;
2083
2084 buf = read_text_file(fname);
2085 if (!buf)
2086 /* No symbol versions, silently ignore */
2087 return;
2088
2089 pos = buf;
2090
2091 while ((line = get_line(&pos))) {
2092 char *symname, *namespace, *modname, *d, *export;
2093 unsigned int crc;
2094 struct module *mod;
2095 struct symbol *s;
2096 bool gpl_only;
2097
2098 if (!(symname = strchr(line, '\t')))
2099 goto fail;
2100 *symname++ = '\0';
2101 if (!(modname = strchr(symname, '\t')))
2102 goto fail;
2103 *modname++ = '\0';
2104 if (!(export = strchr(modname, '\t')))
2105 goto fail;
2106 *export++ = '\0';
2107 if (!(namespace = strchr(export, '\t')))
2108 goto fail;
2109 *namespace++ = '\0';
2110
2111 crc = strtoul(line, &d, 16);
2112 if (*symname == '\0' || *modname == '\0' || *d != '\0')
2113 goto fail;
2114
2115 if (!strcmp(export, "EXPORT_SYMBOL_GPL")) {
2116 gpl_only = true;
2117 } else if (!strcmp(export, "EXPORT_SYMBOL")) {
2118 gpl_only = false;
2119 } else {
2120 error("%s: unknown license %s. skip", symname, export);
2121 continue;
2122 }
2123
2124 mod = find_module(modname);
2125 if (!mod) {
2126 mod = new_module(modname, strlen(modname));
2127 mod->from_dump = true;
2128 }
2129 s = sym_add_exported(symname, mod, gpl_only, namespace);
2130 sym_set_crc(s, crc);
2131 }
2132 free(buf);
2133 return;
2134fail:
2135 free(buf);
2136 fatal("parse error in symbol dump file\n");
2137}
2138
2139static void write_dump(const char *fname)
2140{
2141 struct buffer buf = { };
2142 struct module *mod;
2143 struct symbol *sym;
2144
2145 list_for_each_entry(mod, &modules, list) {
2146 if (mod->from_dump)
2147 continue;
2148 list_for_each_entry(sym, &mod->exported_symbols, list) {
2149 if (trim_unused_exports && !sym->used)
2150 continue;
2151
2152 buf_printf(&buf, "0x%08x\t%s\t%s\tEXPORT_SYMBOL%s\t%s\n",
2153 sym->crc, sym->name, mod->name,
2154 sym->is_gpl_only ? "_GPL" : "",
2155 sym->namespace);
2156 }
2157 }
2158 write_buf(&buf, fname);
2159 free(buf.p);
2160}
2161
2162static void write_namespace_deps_files(const char *fname)
2163{
2164 struct module *mod;
2165 struct namespace_list *ns;
2166 struct buffer ns_deps_buf = {};
2167
2168 list_for_each_entry(mod, &modules, list) {
2169
2170 if (mod->from_dump || list_empty(&mod->missing_namespaces))
2171 continue;
2172
2173 buf_printf(&ns_deps_buf, "%s.ko:", mod->name);
2174
2175 list_for_each_entry(ns, &mod->missing_namespaces, list)
2176 buf_printf(&ns_deps_buf, " %s", ns->namespace);
2177
2178 buf_printf(&ns_deps_buf, "\n");
2179 }
2180
2181 write_if_changed(&ns_deps_buf, fname);
2182 free(ns_deps_buf.p);
2183}
2184
2185struct dump_list {
2186 struct list_head list;
2187 const char *file;
2188};
2189
2190int main(int argc, char **argv)
2191{
2192 struct module *mod;
2193 char *missing_namespace_deps = NULL;
2194 char *unused_exports_white_list = NULL;
2195 char *dump_write = NULL, *files_source = NULL;
2196 int opt;
2197 LIST_HEAD(dump_lists);
2198 struct dump_list *dl, *dl2;
2199
2200 while ((opt = getopt(argc, argv, "ei:MmnT:to:au:WwENd:")) != -1) {
2201 switch (opt) {
2202 case 'e':
2203 external_module = true;
2204 break;
2205 case 'i':
2206 dl = NOFAIL(malloc(sizeof(*dl)));
2207 dl->file = optarg;
2208 list_add_tail(&dl->list, &dump_lists);
2209 break;
2210 case 'M':
2211 module_enabled = true;
2212 break;
2213 case 'm':
2214 modversions = true;
2215 break;
2216 case 'n':
2217 ignore_missing_files = true;
2218 break;
2219 case 'o':
2220 dump_write = optarg;
2221 break;
2222 case 'a':
2223 all_versions = true;
2224 break;
2225 case 'T':
2226 files_source = optarg;
2227 break;
2228 case 't':
2229 trim_unused_exports = true;
2230 break;
2231 case 'u':
2232 unused_exports_white_list = optarg;
2233 break;
2234 case 'W':
2235 extra_warn = true;
2236 break;
2237 case 'w':
2238 warn_unresolved = true;
2239 break;
2240 case 'E':
2241 sec_mismatch_warn_only = false;
2242 break;
2243 case 'N':
2244 allow_missing_ns_imports = true;
2245 break;
2246 case 'd':
2247 missing_namespace_deps = optarg;
2248 break;
2249 default:
2250 exit(1);
2251 }
2252 }
2253
2254 list_for_each_entry_safe(dl, dl2, &dump_lists, list) {
2255 read_dump(dl->file);
2256 list_del(&dl->list);
2257 free(dl);
2258 }
2259
2260 while (optind < argc)
2261 read_symbols(argv[optind++]);
2262
2263 if (files_source)
2264 read_symbols_from_files(files_source);
2265
2266 list_for_each_entry(mod, &modules, list) {
2267 if (mod->from_dump || mod->is_vmlinux)
2268 continue;
2269
2270 check_modname_len(mod);
2271 check_exports(mod);
2272 }
2273
2274 if (unused_exports_white_list)
2275 handle_white_list_exports(unused_exports_white_list);
2276
2277 list_for_each_entry(mod, &modules, list) {
2278 if (mod->from_dump)
2279 continue;
2280
2281 if (mod->is_vmlinux)
2282 write_vmlinux_export_c_file(mod);
2283 else
2284 write_mod_c_file(mod);
2285 }
2286
2287 if (missing_namespace_deps)
2288 write_namespace_deps_files(missing_namespace_deps);
2289
2290 if (dump_write)
2291 write_dump(dump_write);
2292 if (sec_mismatch_count && !sec_mismatch_warn_only)
2293 error("Section mismatches detected.\n"
2294 "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n");
2295
2296 if (nr_unresolved > MAX_UNRESOLVED_REPORTS)
2297 warn("suppressed %u unresolved symbol warnings because there were too many)\n",
2298 nr_unresolved - MAX_UNRESOLVED_REPORTS);
2299
2300 return error_occurred ? 1 : 0;
2301}