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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 <stdio.h>
17#include <ctype.h>
18#include <string.h>
19#include <limits.h>
20#include <stdbool.h>
21#include <errno.h>
22#include "modpost.h"
23#include "../../include/linux/license.h"
24
25/* Are we using CONFIG_MODVERSIONS? */
26static int modversions = 0;
27/* Warn about undefined symbols? (do so if we have vmlinux) */
28static int have_vmlinux = 0;
29/* Is CONFIG_MODULE_SRCVERSION_ALL set? */
30static int all_versions = 0;
31/* If we are modposting external module set to 1 */
32static int external_module = 0;
33/* Only warn about unresolved symbols */
34static int warn_unresolved = 0;
35/* How a symbol is exported */
36static int sec_mismatch_count = 0;
37static int sec_mismatch_fatal = 0;
38/* ignore missing files */
39static int ignore_missing_files;
40/* If set to 1, only warn (instead of error) about missing ns imports */
41static int allow_missing_ns_imports;
42
43enum export {
44 export_plain, export_unused, export_gpl,
45 export_unused_gpl, export_gpl_future, export_unknown
46};
47
48/* In kernel, this size is defined in linux/module.h;
49 * here we use Elf_Addr instead of long for covering cross-compile
50 */
51
52#define MODULE_NAME_LEN (64 - sizeof(Elf_Addr))
53
54void __attribute__((format(printf, 2, 3)))
55modpost_log(enum loglevel loglevel, const char *fmt, ...)
56{
57 va_list arglist;
58
59 switch (loglevel) {
60 case LOG_WARN:
61 fprintf(stderr, "WARNING: ");
62 break;
63 case LOG_ERROR:
64 fprintf(stderr, "ERROR: ");
65 break;
66 case LOG_FATAL:
67 fprintf(stderr, "FATAL: ");
68 break;
69 default: /* invalid loglevel, ignore */
70 break;
71 }
72
73 fprintf(stderr, "modpost: ");
74
75 va_start(arglist, fmt);
76 vfprintf(stderr, fmt, arglist);
77 va_end(arglist);
78
79 if (loglevel == LOG_FATAL)
80 exit(1);
81}
82
83static inline bool strends(const char *str, const char *postfix)
84{
85 if (strlen(str) < strlen(postfix))
86 return false;
87
88 return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0;
89}
90
91void *do_nofail(void *ptr, const char *expr)
92{
93 if (!ptr)
94 fatal("Memory allocation failure: %s.\n", expr);
95
96 return ptr;
97}
98
99char *read_text_file(const char *filename)
100{
101 struct stat st;
102 size_t nbytes;
103 int fd;
104 char *buf;
105
106 fd = open(filename, O_RDONLY);
107 if (fd < 0) {
108 perror(filename);
109 exit(1);
110 }
111
112 if (fstat(fd, &st) < 0) {
113 perror(filename);
114 exit(1);
115 }
116
117 buf = NOFAIL(malloc(st.st_size + 1));
118
119 nbytes = st.st_size;
120
121 while (nbytes) {
122 ssize_t bytes_read;
123
124 bytes_read = read(fd, buf, nbytes);
125 if (bytes_read < 0) {
126 perror(filename);
127 exit(1);
128 }
129
130 nbytes -= bytes_read;
131 }
132 buf[st.st_size] = '\0';
133
134 close(fd);
135
136 return buf;
137}
138
139char *get_line(char **stringp)
140{
141 char *orig = *stringp, *next;
142
143 /* do not return the unwanted extra line at EOF */
144 if (!orig || *orig == '\0')
145 return NULL;
146
147 /* don't use strsep here, it is not available everywhere */
148 next = strchr(orig, '\n');
149 if (next)
150 *next++ = '\0';
151
152 *stringp = next;
153
154 return orig;
155}
156
157/* A list of all modules we processed */
158static struct module *modules;
159
160static struct module *find_module(const char *modname)
161{
162 struct module *mod;
163
164 for (mod = modules; mod; mod = mod->next)
165 if (strcmp(mod->name, modname) == 0)
166 break;
167 return mod;
168}
169
170static struct module *new_module(const char *modname)
171{
172 struct module *mod;
173
174 mod = NOFAIL(malloc(sizeof(*mod) + strlen(modname) + 1));
175 memset(mod, 0, sizeof(*mod));
176
177 /* add to list */
178 strcpy(mod->name, modname);
179 mod->is_vmlinux = (strcmp(modname, "vmlinux") == 0);
180 mod->gpl_compatible = -1;
181 mod->next = modules;
182 modules = mod;
183
184 if (mod->is_vmlinux)
185 have_vmlinux = 1;
186
187 return mod;
188}
189
190/* A hash of all exported symbols,
191 * struct symbol is also used for lists of unresolved symbols */
192
193#define SYMBOL_HASH_SIZE 1024
194
195struct symbol {
196 struct symbol *next;
197 struct module *module;
198 unsigned int crc;
199 int crc_valid;
200 char *namespace;
201 unsigned int weak:1;
202 unsigned int is_static:1; /* 1 if symbol is not global */
203 enum export export; /* Type of export */
204 char name[];
205};
206
207static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
208
209/* This is based on the hash agorithm from gdbm, via tdb */
210static inline unsigned int tdb_hash(const char *name)
211{
212 unsigned value; /* Used to compute the hash value. */
213 unsigned i; /* Used to cycle through random values. */
214
215 /* Set the initial value from the key size. */
216 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++)
217 value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
218
219 return (1103515243 * value + 12345);
220}
221
222/**
223 * Allocate a new symbols for use in the hash of exported symbols or
224 * the list of unresolved symbols per module
225 **/
226static struct symbol *alloc_symbol(const char *name, unsigned int weak,
227 struct symbol *next)
228{
229 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
230
231 memset(s, 0, sizeof(*s));
232 strcpy(s->name, name);
233 s->weak = weak;
234 s->next = next;
235 s->is_static = 1;
236 return s;
237}
238
239/* For the hash of exported symbols */
240static struct symbol *new_symbol(const char *name, struct module *module,
241 enum export export)
242{
243 unsigned int hash;
244
245 hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
246 symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
247
248 return symbolhash[hash];
249}
250
251static struct symbol *find_symbol(const char *name)
252{
253 struct symbol *s;
254
255 /* For our purposes, .foo matches foo. PPC64 needs this. */
256 if (name[0] == '.')
257 name++;
258
259 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
260 if (strcmp(s->name, name) == 0)
261 return s;
262 }
263 return NULL;
264}
265
266static bool contains_namespace(struct namespace_list *list,
267 const char *namespace)
268{
269 for (; list; list = list->next)
270 if (!strcmp(list->namespace, namespace))
271 return true;
272
273 return false;
274}
275
276static void add_namespace(struct namespace_list **list, const char *namespace)
277{
278 struct namespace_list *ns_entry;
279
280 if (!contains_namespace(*list, namespace)) {
281 ns_entry = NOFAIL(malloc(sizeof(struct namespace_list) +
282 strlen(namespace) + 1));
283 strcpy(ns_entry->namespace, namespace);
284 ns_entry->next = *list;
285 *list = ns_entry;
286 }
287}
288
289static bool module_imports_namespace(struct module *module,
290 const char *namespace)
291{
292 return contains_namespace(module->imported_namespaces, namespace);
293}
294
295static const struct {
296 const char *str;
297 enum export export;
298} export_list[] = {
299 { .str = "EXPORT_SYMBOL", .export = export_plain },
300 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
301 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
302 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
303 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
304 { .str = "(unknown)", .export = export_unknown },
305};
306
307
308static const char *export_str(enum export ex)
309{
310 return export_list[ex].str;
311}
312
313static enum export export_no(const char *s)
314{
315 int i;
316
317 if (!s)
318 return export_unknown;
319 for (i = 0; export_list[i].export != export_unknown; i++) {
320 if (strcmp(export_list[i].str, s) == 0)
321 return export_list[i].export;
322 }
323 return export_unknown;
324}
325
326static void *sym_get_data_by_offset(const struct elf_info *info,
327 unsigned int secindex, unsigned long offset)
328{
329 Elf_Shdr *sechdr = &info->sechdrs[secindex];
330
331 if (info->hdr->e_type != ET_REL)
332 offset -= sechdr->sh_addr;
333
334 return (void *)info->hdr + sechdr->sh_offset + offset;
335}
336
337static void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym)
338{
339 return sym_get_data_by_offset(info, get_secindex(info, sym),
340 sym->st_value);
341}
342
343static const char *sech_name(const struct elf_info *info, Elf_Shdr *sechdr)
344{
345 return sym_get_data_by_offset(info, info->secindex_strings,
346 sechdr->sh_name);
347}
348
349static const char *sec_name(const struct elf_info *info, int secindex)
350{
351 return sech_name(info, &info->sechdrs[secindex]);
352}
353
354#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
355
356static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
357{
358 const char *secname = sec_name(elf, sec);
359
360 if (strstarts(secname, "___ksymtab+"))
361 return export_plain;
362 else if (strstarts(secname, "___ksymtab_unused+"))
363 return export_unused;
364 else if (strstarts(secname, "___ksymtab_gpl+"))
365 return export_gpl;
366 else if (strstarts(secname, "___ksymtab_unused_gpl+"))
367 return export_unused_gpl;
368 else if (strstarts(secname, "___ksymtab_gpl_future+"))
369 return export_gpl_future;
370 else
371 return export_unknown;
372}
373
374static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
375{
376 if (sec == elf->export_sec)
377 return export_plain;
378 else if (sec == elf->export_unused_sec)
379 return export_unused;
380 else if (sec == elf->export_gpl_sec)
381 return export_gpl;
382 else if (sec == elf->export_unused_gpl_sec)
383 return export_unused_gpl;
384 else if (sec == elf->export_gpl_future_sec)
385 return export_gpl_future;
386 else
387 return export_unknown;
388}
389
390static const char *namespace_from_kstrtabns(const struct elf_info *info,
391 const Elf_Sym *sym)
392{
393 const char *value = sym_get_data(info, sym);
394 return value[0] ? value : NULL;
395}
396
397static void sym_update_namespace(const char *symname, const char *namespace)
398{
399 struct symbol *s = find_symbol(symname);
400
401 /*
402 * That symbol should have been created earlier and thus this is
403 * actually an assertion.
404 */
405 if (!s) {
406 merror("Could not update namespace(%s) for symbol %s\n",
407 namespace, symname);
408 return;
409 }
410
411 free(s->namespace);
412 s->namespace =
413 namespace && namespace[0] ? NOFAIL(strdup(namespace)) : NULL;
414}
415
416/**
417 * Add an exported symbol - it may have already been added without a
418 * CRC, in this case just update the CRC
419 **/
420static struct symbol *sym_add_exported(const char *name, struct module *mod,
421 enum export export)
422{
423 struct symbol *s = find_symbol(name);
424
425 if (!s) {
426 s = new_symbol(name, mod, export);
427 } else if (!external_module || s->module->is_vmlinux ||
428 s->module == mod) {
429 warn("%s: '%s' exported twice. Previous export was in %s%s\n",
430 mod->name, name, s->module->name,
431 s->module->is_vmlinux ? "" : ".ko");
432 return s;
433 }
434
435 s->module = mod;
436 s->export = export;
437 return s;
438}
439
440static void sym_set_crc(const char *name, unsigned int crc)
441{
442 struct symbol *s = find_symbol(name);
443
444 /*
445 * Ignore stand-alone __crc_*, which might be auto-generated symbols
446 * such as __*_veneer in ARM ELF.
447 */
448 if (!s)
449 return;
450
451 s->crc = crc;
452 s->crc_valid = 1;
453}
454
455static void *grab_file(const char *filename, size_t *size)
456{
457 struct stat st;
458 void *map = MAP_FAILED;
459 int fd;
460
461 fd = open(filename, O_RDONLY);
462 if (fd < 0)
463 return NULL;
464 if (fstat(fd, &st))
465 goto failed;
466
467 *size = st.st_size;
468 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
469
470failed:
471 close(fd);
472 if (map == MAP_FAILED)
473 return NULL;
474 return map;
475}
476
477static void release_file(void *file, size_t size)
478{
479 munmap(file, size);
480}
481
482static int parse_elf(struct elf_info *info, const char *filename)
483{
484 unsigned int i;
485 Elf_Ehdr *hdr;
486 Elf_Shdr *sechdrs;
487 Elf_Sym *sym;
488 const char *secstrings;
489 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
490
491 hdr = grab_file(filename, &info->size);
492 if (!hdr) {
493 if (ignore_missing_files) {
494 fprintf(stderr, "%s: %s (ignored)\n", filename,
495 strerror(errno));
496 return 0;
497 }
498 perror(filename);
499 exit(1);
500 }
501 info->hdr = hdr;
502 if (info->size < sizeof(*hdr)) {
503 /* file too small, assume this is an empty .o file */
504 return 0;
505 }
506 /* Is this a valid ELF file? */
507 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
508 (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
509 (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
510 (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
511 /* Not an ELF file - silently ignore it */
512 return 0;
513 }
514 /* Fix endianness in ELF header */
515 hdr->e_type = TO_NATIVE(hdr->e_type);
516 hdr->e_machine = TO_NATIVE(hdr->e_machine);
517 hdr->e_version = TO_NATIVE(hdr->e_version);
518 hdr->e_entry = TO_NATIVE(hdr->e_entry);
519 hdr->e_phoff = TO_NATIVE(hdr->e_phoff);
520 hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
521 hdr->e_flags = TO_NATIVE(hdr->e_flags);
522 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize);
523 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
524 hdr->e_phnum = TO_NATIVE(hdr->e_phnum);
525 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
526 hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
527 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
528 sechdrs = (void *)hdr + hdr->e_shoff;
529 info->sechdrs = sechdrs;
530
531 /* Check if file offset is correct */
532 if (hdr->e_shoff > info->size) {
533 fatal("section header offset=%lu in file '%s' is bigger than filesize=%zu\n",
534 (unsigned long)hdr->e_shoff, filename, info->size);
535 return 0;
536 }
537
538 if (hdr->e_shnum == SHN_UNDEF) {
539 /*
540 * There are more than 64k sections,
541 * read count from .sh_size.
542 */
543 info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
544 }
545 else {
546 info->num_sections = hdr->e_shnum;
547 }
548 if (hdr->e_shstrndx == SHN_XINDEX) {
549 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
550 }
551 else {
552 info->secindex_strings = hdr->e_shstrndx;
553 }
554
555 /* Fix endianness in section headers */
556 for (i = 0; i < info->num_sections; i++) {
557 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
558 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
559 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
560 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
561 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
562 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
563 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
564 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
565 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
566 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
567 }
568 /* Find symbol table. */
569 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
570 for (i = 1; i < info->num_sections; i++) {
571 const char *secname;
572 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
573
574 if (!nobits && sechdrs[i].sh_offset > info->size) {
575 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
576 "sizeof(*hrd)=%zu\n", filename,
577 (unsigned long)sechdrs[i].sh_offset,
578 sizeof(*hdr));
579 return 0;
580 }
581 secname = secstrings + sechdrs[i].sh_name;
582 if (strcmp(secname, ".modinfo") == 0) {
583 if (nobits)
584 fatal("%s has NOBITS .modinfo\n", filename);
585 info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
586 info->modinfo_len = sechdrs[i].sh_size;
587 } else if (strcmp(secname, "__ksymtab") == 0)
588 info->export_sec = i;
589 else if (strcmp(secname, "__ksymtab_unused") == 0)
590 info->export_unused_sec = i;
591 else if (strcmp(secname, "__ksymtab_gpl") == 0)
592 info->export_gpl_sec = i;
593 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
594 info->export_unused_gpl_sec = i;
595 else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
596 info->export_gpl_future_sec = i;
597
598 if (sechdrs[i].sh_type == SHT_SYMTAB) {
599 unsigned int sh_link_idx;
600 symtab_idx = i;
601 info->symtab_start = (void *)hdr +
602 sechdrs[i].sh_offset;
603 info->symtab_stop = (void *)hdr +
604 sechdrs[i].sh_offset + sechdrs[i].sh_size;
605 sh_link_idx = sechdrs[i].sh_link;
606 info->strtab = (void *)hdr +
607 sechdrs[sh_link_idx].sh_offset;
608 }
609
610 /* 32bit section no. table? ("more than 64k sections") */
611 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
612 symtab_shndx_idx = i;
613 info->symtab_shndx_start = (void *)hdr +
614 sechdrs[i].sh_offset;
615 info->symtab_shndx_stop = (void *)hdr +
616 sechdrs[i].sh_offset + sechdrs[i].sh_size;
617 }
618 }
619 if (!info->symtab_start)
620 fatal("%s has no symtab?\n", filename);
621
622 /* Fix endianness in symbols */
623 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
624 sym->st_shndx = TO_NATIVE(sym->st_shndx);
625 sym->st_name = TO_NATIVE(sym->st_name);
626 sym->st_value = TO_NATIVE(sym->st_value);
627 sym->st_size = TO_NATIVE(sym->st_size);
628 }
629
630 if (symtab_shndx_idx != ~0U) {
631 Elf32_Word *p;
632 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
633 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
634 filename, sechdrs[symtab_shndx_idx].sh_link,
635 symtab_idx);
636 /* Fix endianness */
637 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
638 p++)
639 *p = TO_NATIVE(*p);
640 }
641
642 return 1;
643}
644
645static void parse_elf_finish(struct elf_info *info)
646{
647 release_file(info->hdr, info->size);
648}
649
650static int ignore_undef_symbol(struct elf_info *info, const char *symname)
651{
652 /* ignore __this_module, it will be resolved shortly */
653 if (strcmp(symname, "__this_module") == 0)
654 return 1;
655 /* ignore global offset table */
656 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
657 return 1;
658 if (info->hdr->e_machine == EM_PPC)
659 /* Special register function linked on all modules during final link of .ko */
660 if (strstarts(symname, "_restgpr_") ||
661 strstarts(symname, "_savegpr_") ||
662 strstarts(symname, "_rest32gpr_") ||
663 strstarts(symname, "_save32gpr_") ||
664 strstarts(symname, "_restvr_") ||
665 strstarts(symname, "_savevr_"))
666 return 1;
667 if (info->hdr->e_machine == EM_PPC64)
668 /* Special register function linked on all modules during final link of .ko */
669 if (strstarts(symname, "_restgpr0_") ||
670 strstarts(symname, "_savegpr0_") ||
671 strstarts(symname, "_restvr_") ||
672 strstarts(symname, "_savevr_") ||
673 strcmp(symname, ".TOC.") == 0)
674 return 1;
675 /* Do not ignore this symbol */
676 return 0;
677}
678
679static void handle_modversion(const struct module *mod,
680 const struct elf_info *info,
681 const Elf_Sym *sym, const char *symname)
682{
683 unsigned int crc;
684
685 if (sym->st_shndx == SHN_UNDEF) {
686 warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n",
687 symname, mod->name, mod->is_vmlinux ? "" : ".ko");
688 return;
689 }
690
691 if (sym->st_shndx == SHN_ABS) {
692 crc = sym->st_value;
693 } else {
694 unsigned int *crcp;
695
696 /* symbol points to the CRC in the ELF object */
697 crcp = sym_get_data(info, sym);
698 crc = TO_NATIVE(*crcp);
699 }
700 sym_set_crc(symname, crc);
701}
702
703static void handle_symbol(struct module *mod, struct elf_info *info,
704 const Elf_Sym *sym, const char *symname)
705{
706 enum export export;
707 const char *name;
708
709 if (strstarts(symname, "__ksymtab"))
710 export = export_from_secname(info, get_secindex(info, sym));
711 else
712 export = export_from_sec(info, get_secindex(info, sym));
713
714 switch (sym->st_shndx) {
715 case SHN_COMMON:
716 if (strstarts(symname, "__gnu_lto_")) {
717 /* Should warn here, but modpost runs before the linker */
718 } else
719 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
720 break;
721 case SHN_UNDEF:
722 /* undefined symbol */
723 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
724 ELF_ST_BIND(sym->st_info) != STB_WEAK)
725 break;
726 if (ignore_undef_symbol(info, symname))
727 break;
728 if (info->hdr->e_machine == EM_SPARC ||
729 info->hdr->e_machine == EM_SPARCV9) {
730 /* Ignore register directives. */
731 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
732 break;
733 if (symname[0] == '.') {
734 char *munged = NOFAIL(strdup(symname));
735 munged[0] = '_';
736 munged[1] = toupper(munged[1]);
737 symname = munged;
738 }
739 }
740
741 mod->unres = alloc_symbol(symname,
742 ELF_ST_BIND(sym->st_info) == STB_WEAK,
743 mod->unres);
744 break;
745 default:
746 /* All exported symbols */
747 if (strstarts(symname, "__ksymtab_")) {
748 name = symname + strlen("__ksymtab_");
749 sym_add_exported(name, mod, export);
750 }
751 if (strcmp(symname, "init_module") == 0)
752 mod->has_init = 1;
753 if (strcmp(symname, "cleanup_module") == 0)
754 mod->has_cleanup = 1;
755 break;
756 }
757}
758
759/**
760 * Parse tag=value strings from .modinfo section
761 **/
762static char *next_string(char *string, unsigned long *secsize)
763{
764 /* Skip non-zero chars */
765 while (string[0]) {
766 string++;
767 if ((*secsize)-- <= 1)
768 return NULL;
769 }
770
771 /* Skip any zero padding. */
772 while (!string[0]) {
773 string++;
774 if ((*secsize)-- <= 1)
775 return NULL;
776 }
777 return string;
778}
779
780static char *get_next_modinfo(struct elf_info *info, const char *tag,
781 char *prev)
782{
783 char *p;
784 unsigned int taglen = strlen(tag);
785 char *modinfo = info->modinfo;
786 unsigned long size = info->modinfo_len;
787
788 if (prev) {
789 size -= prev - modinfo;
790 modinfo = next_string(prev, &size);
791 }
792
793 for (p = modinfo; p; p = next_string(p, &size)) {
794 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
795 return p + taglen + 1;
796 }
797 return NULL;
798}
799
800static char *get_modinfo(struct elf_info *info, const char *tag)
801
802{
803 return get_next_modinfo(info, tag, NULL);
804}
805
806/**
807 * Test if string s ends in string sub
808 * return 0 if match
809 **/
810static int strrcmp(const char *s, const char *sub)
811{
812 int slen, sublen;
813
814 if (!s || !sub)
815 return 1;
816
817 slen = strlen(s);
818 sublen = strlen(sub);
819
820 if ((slen == 0) || (sublen == 0))
821 return 1;
822
823 if (sublen > slen)
824 return 1;
825
826 return memcmp(s + slen - sublen, sub, sublen);
827}
828
829static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
830{
831 if (sym)
832 return elf->strtab + sym->st_name;
833 else
834 return "(unknown)";
835}
836
837/* The pattern is an array of simple patterns.
838 * "foo" will match an exact string equal to "foo"
839 * "*foo" will match a string that ends with "foo"
840 * "foo*" will match a string that begins with "foo"
841 * "*foo*" will match a string that contains "foo"
842 */
843static int match(const char *sym, const char * const pat[])
844{
845 const char *p;
846 while (*pat) {
847 p = *pat++;
848 const char *endp = p + strlen(p) - 1;
849
850 /* "*foo*" */
851 if (*p == '*' && *endp == '*') {
852 char *bare = NOFAIL(strndup(p + 1, strlen(p) - 2));
853 char *here = strstr(sym, bare);
854
855 free(bare);
856 if (here != NULL)
857 return 1;
858 }
859 /* "*foo" */
860 else if (*p == '*') {
861 if (strrcmp(sym, p + 1) == 0)
862 return 1;
863 }
864 /* "foo*" */
865 else if (*endp == '*') {
866 if (strncmp(sym, p, strlen(p) - 1) == 0)
867 return 1;
868 }
869 /* no wildcards */
870 else {
871 if (strcmp(p, sym) == 0)
872 return 1;
873 }
874 }
875 /* no match */
876 return 0;
877}
878
879/* sections that we do not want to do full section mismatch check on */
880static const char *const section_white_list[] =
881{
882 ".comment*",
883 ".debug*",
884 ".cranges", /* sh64 */
885 ".zdebug*", /* Compressed debug sections. */
886 ".GCC.command.line", /* record-gcc-switches */
887 ".mdebug*", /* alpha, score, mips etc. */
888 ".pdr", /* alpha, score, mips etc. */
889 ".stab*",
890 ".note*",
891 ".got*",
892 ".toc*",
893 ".xt.prop", /* xtensa */
894 ".xt.lit", /* xtensa */
895 ".arcextmap*", /* arc */
896 ".gnu.linkonce.arcext*", /* arc : modules */
897 ".cmem*", /* EZchip */
898 ".fmt_slot*", /* EZchip */
899 ".gnu.lto*",
900 ".discard.*",
901 NULL
902};
903
904/*
905 * This is used to find sections missing the SHF_ALLOC flag.
906 * The cause of this is often a section specified in assembler
907 * without "ax" / "aw".
908 */
909static void check_section(const char *modname, struct elf_info *elf,
910 Elf_Shdr *sechdr)
911{
912 const char *sec = sech_name(elf, sechdr);
913
914 if (sechdr->sh_type == SHT_PROGBITS &&
915 !(sechdr->sh_flags & SHF_ALLOC) &&
916 !match(sec, section_white_list)) {
917 warn("%s (%s): unexpected non-allocatable section.\n"
918 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
919 "Note that for example <linux/init.h> contains\n"
920 "section definitions for use in .S files.\n\n",
921 modname, sec);
922 }
923}
924
925
926
927#define ALL_INIT_DATA_SECTIONS \
928 ".init.setup", ".init.rodata", ".meminit.rodata", \
929 ".init.data", ".meminit.data"
930#define ALL_EXIT_DATA_SECTIONS \
931 ".exit.data", ".memexit.data"
932
933#define ALL_INIT_TEXT_SECTIONS \
934 ".init.text", ".meminit.text"
935#define ALL_EXIT_TEXT_SECTIONS \
936 ".exit.text", ".memexit.text"
937
938#define ALL_PCI_INIT_SECTIONS \
939 ".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \
940 ".pci_fixup_enable", ".pci_fixup_resume", \
941 ".pci_fixup_resume_early", ".pci_fixup_suspend"
942
943#define ALL_XXXINIT_SECTIONS MEM_INIT_SECTIONS
944#define ALL_XXXEXIT_SECTIONS MEM_EXIT_SECTIONS
945
946#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
947#define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
948
949#define DATA_SECTIONS ".data", ".data.rel"
950#define TEXT_SECTIONS ".text", ".text.unlikely", ".sched.text", \
951 ".kprobes.text", ".cpuidle.text", ".noinstr.text"
952#define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \
953 ".fixup", ".entry.text", ".exception.text", ".text.*", \
954 ".coldtext"
955
956#define INIT_SECTIONS ".init.*"
957#define MEM_INIT_SECTIONS ".meminit.*"
958
959#define EXIT_SECTIONS ".exit.*"
960#define MEM_EXIT_SECTIONS ".memexit.*"
961
962#define ALL_TEXT_SECTIONS ALL_INIT_TEXT_SECTIONS, ALL_EXIT_TEXT_SECTIONS, \
963 TEXT_SECTIONS, OTHER_TEXT_SECTIONS
964
965/* init data sections */
966static const char *const init_data_sections[] =
967 { ALL_INIT_DATA_SECTIONS, NULL };
968
969/* all init sections */
970static const char *const init_sections[] = { ALL_INIT_SECTIONS, NULL };
971
972/* All init and exit sections (code + data) */
973static const char *const init_exit_sections[] =
974 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
975
976/* all text sections */
977static const char *const text_sections[] = { ALL_TEXT_SECTIONS, NULL };
978
979/* data section */
980static const char *const data_sections[] = { DATA_SECTIONS, NULL };
981
982
983/* symbols in .data that may refer to init/exit sections */
984#define DEFAULT_SYMBOL_WHITE_LIST \
985 "*driver", \
986 "*_template", /* scsi uses *_template a lot */ \
987 "*_timer", /* arm uses ops structures named _timer a lot */ \
988 "*_sht", /* scsi also used *_sht to some extent */ \
989 "*_ops", \
990 "*_probe", \
991 "*_probe_one", \
992 "*_console"
993
994static const char *const head_sections[] = { ".head.text*", NULL };
995static const char *const linker_symbols[] =
996 { "__init_begin", "_sinittext", "_einittext", NULL };
997static const char *const optim_symbols[] = { "*.constprop.*", NULL };
998
999enum mismatch {
1000 TEXT_TO_ANY_INIT,
1001 DATA_TO_ANY_INIT,
1002 TEXT_TO_ANY_EXIT,
1003 DATA_TO_ANY_EXIT,
1004 XXXINIT_TO_SOME_INIT,
1005 XXXEXIT_TO_SOME_EXIT,
1006 ANY_INIT_TO_ANY_EXIT,
1007 ANY_EXIT_TO_ANY_INIT,
1008 EXPORT_TO_INIT_EXIT,
1009 EXTABLE_TO_NON_TEXT,
1010};
1011
1012/**
1013 * Describe how to match sections on different criterias:
1014 *
1015 * @fromsec: Array of sections to be matched.
1016 *
1017 * @bad_tosec: Relocations applied to a section in @fromsec to a section in
1018 * this array is forbidden (black-list). Can be empty.
1019 *
1020 * @good_tosec: Relocations applied to a section in @fromsec must be
1021 * targetting sections in this array (white-list). Can be empty.
1022 *
1023 * @mismatch: Type of mismatch.
1024 *
1025 * @symbol_white_list: Do not match a relocation to a symbol in this list
1026 * even if it is targetting a section in @bad_to_sec.
1027 *
1028 * @handler: Specific handler to call when a match is found. If NULL,
1029 * default_mismatch_handler() will be called.
1030 *
1031 */
1032struct sectioncheck {
1033 const char *fromsec[20];
1034 const char *bad_tosec[20];
1035 const char *good_tosec[20];
1036 enum mismatch mismatch;
1037 const char *symbol_white_list[20];
1038 void (*handler)(const char *modname, struct elf_info *elf,
1039 const struct sectioncheck* const mismatch,
1040 Elf_Rela *r, Elf_Sym *sym, const char *fromsec);
1041
1042};
1043
1044static void extable_mismatch_handler(const char *modname, struct elf_info *elf,
1045 const struct sectioncheck* const mismatch,
1046 Elf_Rela *r, Elf_Sym *sym,
1047 const char *fromsec);
1048
1049static const struct sectioncheck sectioncheck[] = {
1050/* Do not reference init/exit code/data from
1051 * normal code and data
1052 */
1053{
1054 .fromsec = { TEXT_SECTIONS, NULL },
1055 .bad_tosec = { ALL_INIT_SECTIONS, NULL },
1056 .mismatch = TEXT_TO_ANY_INIT,
1057 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1058},
1059{
1060 .fromsec = { DATA_SECTIONS, NULL },
1061 .bad_tosec = { ALL_XXXINIT_SECTIONS, NULL },
1062 .mismatch = DATA_TO_ANY_INIT,
1063 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1064},
1065{
1066 .fromsec = { DATA_SECTIONS, NULL },
1067 .bad_tosec = { INIT_SECTIONS, NULL },
1068 .mismatch = DATA_TO_ANY_INIT,
1069 .symbol_white_list = {
1070 "*_template", "*_timer", "*_sht", "*_ops",
1071 "*_probe", "*_probe_one", "*_console", NULL
1072 },
1073},
1074{
1075 .fromsec = { TEXT_SECTIONS, NULL },
1076 .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
1077 .mismatch = TEXT_TO_ANY_EXIT,
1078 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1079},
1080{
1081 .fromsec = { DATA_SECTIONS, NULL },
1082 .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
1083 .mismatch = DATA_TO_ANY_EXIT,
1084 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1085},
1086/* Do not reference init code/data from meminit code/data */
1087{
1088 .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
1089 .bad_tosec = { INIT_SECTIONS, NULL },
1090 .mismatch = XXXINIT_TO_SOME_INIT,
1091 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1092},
1093/* Do not reference exit code/data from memexit code/data */
1094{
1095 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
1096 .bad_tosec = { EXIT_SECTIONS, NULL },
1097 .mismatch = XXXEXIT_TO_SOME_EXIT,
1098 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1099},
1100/* Do not use exit code/data from init code */
1101{
1102 .fromsec = { ALL_INIT_SECTIONS, NULL },
1103 .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
1104 .mismatch = ANY_INIT_TO_ANY_EXIT,
1105 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1106},
1107/* Do not use init code/data from exit code */
1108{
1109 .fromsec = { ALL_EXIT_SECTIONS, NULL },
1110 .bad_tosec = { ALL_INIT_SECTIONS, NULL },
1111 .mismatch = ANY_EXIT_TO_ANY_INIT,
1112 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1113},
1114{
1115 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
1116 .bad_tosec = { INIT_SECTIONS, NULL },
1117 .mismatch = ANY_INIT_TO_ANY_EXIT,
1118 .symbol_white_list = { NULL },
1119},
1120/* Do not export init/exit functions or data */
1121{
1122 .fromsec = { "__ksymtab*", NULL },
1123 .bad_tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
1124 .mismatch = EXPORT_TO_INIT_EXIT,
1125 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1126},
1127{
1128 .fromsec = { "__ex_table", NULL },
1129 /* If you're adding any new black-listed sections in here, consider
1130 * adding a special 'printer' for them in scripts/check_extable.
1131 */
1132 .bad_tosec = { ".altinstr_replacement", NULL },
1133 .good_tosec = {ALL_TEXT_SECTIONS , NULL},
1134 .mismatch = EXTABLE_TO_NON_TEXT,
1135 .handler = extable_mismatch_handler,
1136}
1137};
1138
1139static const struct sectioncheck *section_mismatch(
1140 const char *fromsec, const char *tosec)
1141{
1142 int i;
1143 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
1144 const struct sectioncheck *check = §ioncheck[0];
1145
1146 /*
1147 * The target section could be the SHT_NUL section when we're
1148 * handling relocations to un-resolved symbols, trying to match it
1149 * doesn't make much sense and causes build failures on parisc
1150 * architectures.
1151 */
1152 if (*tosec == '\0')
1153 return NULL;
1154
1155 for (i = 0; i < elems; i++) {
1156 if (match(fromsec, check->fromsec)) {
1157 if (check->bad_tosec[0] && match(tosec, check->bad_tosec))
1158 return check;
1159 if (check->good_tosec[0] && !match(tosec, check->good_tosec))
1160 return check;
1161 }
1162 check++;
1163 }
1164 return NULL;
1165}
1166
1167/**
1168 * Whitelist to allow certain references to pass with no warning.
1169 *
1170 * Pattern 1:
1171 * If a module parameter is declared __initdata and permissions=0
1172 * then this is legal despite the warning generated.
1173 * We cannot see value of permissions here, so just ignore
1174 * this pattern.
1175 * The pattern is identified by:
1176 * tosec = .init.data
1177 * fromsec = .data*
1178 * atsym =__param*
1179 *
1180 * Pattern 1a:
1181 * module_param_call() ops can refer to __init set function if permissions=0
1182 * The pattern is identified by:
1183 * tosec = .init.text
1184 * fromsec = .data*
1185 * atsym = __param_ops_*
1186 *
1187 * Pattern 2:
1188 * Many drivers utilise a *driver container with references to
1189 * add, remove, probe functions etc.
1190 * the pattern is identified by:
1191 * tosec = init or exit section
1192 * fromsec = data section
1193 * atsym = *driver, *_template, *_sht, *_ops, *_probe,
1194 * *probe_one, *_console, *_timer
1195 *
1196 * Pattern 3:
1197 * Whitelist all references from .head.text to any init section
1198 *
1199 * Pattern 4:
1200 * Some symbols belong to init section but still it is ok to reference
1201 * these from non-init sections as these symbols don't have any memory
1202 * allocated for them and symbol address and value are same. So even
1203 * if init section is freed, its ok to reference those symbols.
1204 * For ex. symbols marking the init section boundaries.
1205 * This pattern is identified by
1206 * refsymname = __init_begin, _sinittext, _einittext
1207 *
1208 * Pattern 5:
1209 * GCC may optimize static inlines when fed constant arg(s) resulting
1210 * in functions like cpumask_empty() -- generating an associated symbol
1211 * cpumask_empty.constprop.3 that appears in the audit. If the const that
1212 * is passed in comes from __init, like say nmi_ipi_mask, we get a
1213 * meaningless section warning. May need to add isra symbols too...
1214 * This pattern is identified by
1215 * tosec = init section
1216 * fromsec = text section
1217 * refsymname = *.constprop.*
1218 *
1219 * Pattern 6:
1220 * Hide section mismatch warnings for ELF local symbols. The goal
1221 * is to eliminate false positive modpost warnings caused by
1222 * compiler-generated ELF local symbol names such as ".LANCHOR1".
1223 * Autogenerated symbol names bypass modpost's "Pattern 2"
1224 * whitelisting, which relies on pattern-matching against symbol
1225 * names to work. (One situation where gcc can autogenerate ELF
1226 * local symbols is when "-fsection-anchors" is used.)
1227 **/
1228static int secref_whitelist(const struct sectioncheck *mismatch,
1229 const char *fromsec, const char *fromsym,
1230 const char *tosec, const char *tosym)
1231{
1232 /* Check for pattern 1 */
1233 if (match(tosec, init_data_sections) &&
1234 match(fromsec, data_sections) &&
1235 strstarts(fromsym, "__param"))
1236 return 0;
1237
1238 /* Check for pattern 1a */
1239 if (strcmp(tosec, ".init.text") == 0 &&
1240 match(fromsec, data_sections) &&
1241 strstarts(fromsym, "__param_ops_"))
1242 return 0;
1243
1244 /* Check for pattern 2 */
1245 if (match(tosec, init_exit_sections) &&
1246 match(fromsec, data_sections) &&
1247 match(fromsym, mismatch->symbol_white_list))
1248 return 0;
1249
1250 /* Check for pattern 3 */
1251 if (match(fromsec, head_sections) &&
1252 match(tosec, init_sections))
1253 return 0;
1254
1255 /* Check for pattern 4 */
1256 if (match(tosym, linker_symbols))
1257 return 0;
1258
1259 /* Check for pattern 5 */
1260 if (match(fromsec, text_sections) &&
1261 match(tosec, init_sections) &&
1262 match(fromsym, optim_symbols))
1263 return 0;
1264
1265 /* Check for pattern 6 */
1266 if (strstarts(fromsym, ".L"))
1267 return 0;
1268
1269 return 1;
1270}
1271
1272static inline int is_arm_mapping_symbol(const char *str)
1273{
1274 return str[0] == '$' && strchr("axtd", str[1])
1275 && (str[2] == '\0' || str[2] == '.');
1276}
1277
1278/*
1279 * If there's no name there, ignore it; likewise, ignore it if it's
1280 * one of the magic symbols emitted used by current ARM tools.
1281 *
1282 * Otherwise if find_symbols_between() returns those symbols, they'll
1283 * fail the whitelist tests and cause lots of false alarms ... fixable
1284 * only by merging __exit and __init sections into __text, bloating
1285 * the kernel (which is especially evil on embedded platforms).
1286 */
1287static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
1288{
1289 const char *name = elf->strtab + sym->st_name;
1290
1291 if (!name || !strlen(name))
1292 return 0;
1293 return !is_arm_mapping_symbol(name);
1294}
1295
1296/**
1297 * Find symbol based on relocation record info.
1298 * In some cases the symbol supplied is a valid symbol so
1299 * return refsym. If st_name != 0 we assume this is a valid symbol.
1300 * In other cases the symbol needs to be looked up in the symbol table
1301 * based on section and address.
1302 * **/
1303static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
1304 Elf_Sym *relsym)
1305{
1306 Elf_Sym *sym;
1307 Elf_Sym *near = NULL;
1308 Elf64_Sword distance = 20;
1309 Elf64_Sword d;
1310 unsigned int relsym_secindex;
1311
1312 if (relsym->st_name != 0)
1313 return relsym;
1314
1315 relsym_secindex = get_secindex(elf, relsym);
1316 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1317 if (get_secindex(elf, sym) != relsym_secindex)
1318 continue;
1319 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
1320 continue;
1321 if (!is_valid_name(elf, sym))
1322 continue;
1323 if (sym->st_value == addr)
1324 return sym;
1325 /* Find a symbol nearby - addr are maybe negative */
1326 d = sym->st_value - addr;
1327 if (d < 0)
1328 d = addr - sym->st_value;
1329 if (d < distance) {
1330 distance = d;
1331 near = sym;
1332 }
1333 }
1334 /* We need a close match */
1335 if (distance < 20)
1336 return near;
1337 else
1338 return NULL;
1339}
1340
1341/*
1342 * Find symbols before or equal addr and after addr - in the section sec.
1343 * If we find two symbols with equal offset prefer one with a valid name.
1344 * The ELF format may have a better way to detect what type of symbol
1345 * it is, but this works for now.
1346 **/
1347static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
1348 const char *sec)
1349{
1350 Elf_Sym *sym;
1351 Elf_Sym *near = NULL;
1352 Elf_Addr distance = ~0;
1353
1354 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1355 const char *symsec;
1356
1357 if (is_shndx_special(sym->st_shndx))
1358 continue;
1359 symsec = sec_name(elf, get_secindex(elf, sym));
1360 if (strcmp(symsec, sec) != 0)
1361 continue;
1362 if (!is_valid_name(elf, sym))
1363 continue;
1364 if (sym->st_value <= addr) {
1365 if ((addr - sym->st_value) < distance) {
1366 distance = addr - sym->st_value;
1367 near = sym;
1368 } else if ((addr - sym->st_value) == distance) {
1369 near = sym;
1370 }
1371 }
1372 }
1373 return near;
1374}
1375
1376/*
1377 * Convert a section name to the function/data attribute
1378 * .init.text => __init
1379 * .memexitconst => __memconst
1380 * etc.
1381 *
1382 * The memory of returned value has been allocated on a heap. The user of this
1383 * method should free it after usage.
1384*/
1385static char *sec2annotation(const char *s)
1386{
1387 if (match(s, init_exit_sections)) {
1388 char *p = NOFAIL(malloc(20));
1389 char *r = p;
1390
1391 *p++ = '_';
1392 *p++ = '_';
1393 if (*s == '.')
1394 s++;
1395 while (*s && *s != '.')
1396 *p++ = *s++;
1397 *p = '\0';
1398 if (*s == '.')
1399 s++;
1400 if (strstr(s, "rodata") != NULL)
1401 strcat(p, "const ");
1402 else if (strstr(s, "data") != NULL)
1403 strcat(p, "data ");
1404 else
1405 strcat(p, " ");
1406 return r;
1407 } else {
1408 return NOFAIL(strdup(""));
1409 }
1410}
1411
1412static int is_function(Elf_Sym *sym)
1413{
1414 if (sym)
1415 return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
1416 else
1417 return -1;
1418}
1419
1420static void print_section_list(const char * const list[20])
1421{
1422 const char *const *s = list;
1423
1424 while (*s) {
1425 fprintf(stderr, "%s", *s);
1426 s++;
1427 if (*s)
1428 fprintf(stderr, ", ");
1429 }
1430 fprintf(stderr, "\n");
1431}
1432
1433static inline void get_pretty_name(int is_func, const char** name, const char** name_p)
1434{
1435 switch (is_func) {
1436 case 0: *name = "variable"; *name_p = ""; break;
1437 case 1: *name = "function"; *name_p = "()"; break;
1438 default: *name = "(unknown reference)"; *name_p = ""; break;
1439 }
1440}
1441
1442/*
1443 * Print a warning about a section mismatch.
1444 * Try to find symbols near it so user can find it.
1445 * Check whitelist before warning - it may be a false positive.
1446 */
1447static void report_sec_mismatch(const char *modname,
1448 const struct sectioncheck *mismatch,
1449 const char *fromsec,
1450 unsigned long long fromaddr,
1451 const char *fromsym,
1452 int from_is_func,
1453 const char *tosec, const char *tosym,
1454 int to_is_func)
1455{
1456 const char *from, *from_p;
1457 const char *to, *to_p;
1458 char *prl_from;
1459 char *prl_to;
1460
1461 sec_mismatch_count++;
1462
1463 get_pretty_name(from_is_func, &from, &from_p);
1464 get_pretty_name(to_is_func, &to, &to_p);
1465
1466 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1467 "to the %s %s:%s%s\n",
1468 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
1469 tosym, to_p);
1470
1471 switch (mismatch->mismatch) {
1472 case TEXT_TO_ANY_INIT:
1473 prl_from = sec2annotation(fromsec);
1474 prl_to = sec2annotation(tosec);
1475 fprintf(stderr,
1476 "The function %s%s() references\n"
1477 "the %s %s%s%s.\n"
1478 "This is often because %s lacks a %s\n"
1479 "annotation or the annotation of %s is wrong.\n",
1480 prl_from, fromsym,
1481 to, prl_to, tosym, to_p,
1482 fromsym, prl_to, tosym);
1483 free(prl_from);
1484 free(prl_to);
1485 break;
1486 case DATA_TO_ANY_INIT: {
1487 prl_to = sec2annotation(tosec);
1488 fprintf(stderr,
1489 "The variable %s references\n"
1490 "the %s %s%s%s\n"
1491 "If the reference is valid then annotate the\n"
1492 "variable with __init* or __refdata (see linux/init.h) "
1493 "or name the variable:\n",
1494 fromsym, to, prl_to, tosym, to_p);
1495 print_section_list(mismatch->symbol_white_list);
1496 free(prl_to);
1497 break;
1498 }
1499 case TEXT_TO_ANY_EXIT:
1500 prl_to = sec2annotation(tosec);
1501 fprintf(stderr,
1502 "The function %s() references a %s in an exit section.\n"
1503 "Often the %s %s%s has valid usage outside the exit section\n"
1504 "and the fix is to remove the %sannotation of %s.\n",
1505 fromsym, to, to, tosym, to_p, prl_to, tosym);
1506 free(prl_to);
1507 break;
1508 case DATA_TO_ANY_EXIT: {
1509 prl_to = sec2annotation(tosec);
1510 fprintf(stderr,
1511 "The variable %s references\n"
1512 "the %s %s%s%s\n"
1513 "If the reference is valid then annotate the\n"
1514 "variable with __exit* (see linux/init.h) or "
1515 "name the variable:\n",
1516 fromsym, to, prl_to, tosym, to_p);
1517 print_section_list(mismatch->symbol_white_list);
1518 free(prl_to);
1519 break;
1520 }
1521 case XXXINIT_TO_SOME_INIT:
1522 case XXXEXIT_TO_SOME_EXIT:
1523 prl_from = sec2annotation(fromsec);
1524 prl_to = sec2annotation(tosec);
1525 fprintf(stderr,
1526 "The %s %s%s%s references\n"
1527 "a %s %s%s%s.\n"
1528 "If %s is only used by %s then\n"
1529 "annotate %s with a matching annotation.\n",
1530 from, prl_from, fromsym, from_p,
1531 to, prl_to, tosym, to_p,
1532 tosym, fromsym, tosym);
1533 free(prl_from);
1534 free(prl_to);
1535 break;
1536 case ANY_INIT_TO_ANY_EXIT:
1537 prl_from = sec2annotation(fromsec);
1538 prl_to = sec2annotation(tosec);
1539 fprintf(stderr,
1540 "The %s %s%s%s references\n"
1541 "a %s %s%s%s.\n"
1542 "This is often seen when error handling "
1543 "in the init function\n"
1544 "uses functionality in the exit path.\n"
1545 "The fix is often to remove the %sannotation of\n"
1546 "%s%s so it may be used outside an exit section.\n",
1547 from, prl_from, fromsym, from_p,
1548 to, prl_to, tosym, to_p,
1549 prl_to, tosym, to_p);
1550 free(prl_from);
1551 free(prl_to);
1552 break;
1553 case ANY_EXIT_TO_ANY_INIT:
1554 prl_from = sec2annotation(fromsec);
1555 prl_to = sec2annotation(tosec);
1556 fprintf(stderr,
1557 "The %s %s%s%s references\n"
1558 "a %s %s%s%s.\n"
1559 "This is often seen when error handling "
1560 "in the exit function\n"
1561 "uses functionality in the init path.\n"
1562 "The fix is often to remove the %sannotation of\n"
1563 "%s%s so it may be used outside an init section.\n",
1564 from, prl_from, fromsym, from_p,
1565 to, prl_to, tosym, to_p,
1566 prl_to, tosym, to_p);
1567 free(prl_from);
1568 free(prl_to);
1569 break;
1570 case EXPORT_TO_INIT_EXIT:
1571 prl_to = sec2annotation(tosec);
1572 fprintf(stderr,
1573 "The symbol %s is exported and annotated %s\n"
1574 "Fix this by removing the %sannotation of %s "
1575 "or drop the export.\n",
1576 tosym, prl_to, prl_to, tosym);
1577 free(prl_to);
1578 break;
1579 case EXTABLE_TO_NON_TEXT:
1580 fatal("There's a special handler for this mismatch type, "
1581 "we should never get here.");
1582 break;
1583 }
1584 fprintf(stderr, "\n");
1585}
1586
1587static void default_mismatch_handler(const char *modname, struct elf_info *elf,
1588 const struct sectioncheck* const mismatch,
1589 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1590{
1591 const char *tosec;
1592 Elf_Sym *to;
1593 Elf_Sym *from;
1594 const char *tosym;
1595 const char *fromsym;
1596
1597 from = find_elf_symbol2(elf, r->r_offset, fromsec);
1598 fromsym = sym_name(elf, from);
1599
1600 if (strstarts(fromsym, "reference___initcall"))
1601 return;
1602
1603 tosec = sec_name(elf, get_secindex(elf, sym));
1604 to = find_elf_symbol(elf, r->r_addend, sym);
1605 tosym = sym_name(elf, to);
1606
1607 /* check whitelist - we may ignore it */
1608 if (secref_whitelist(mismatch,
1609 fromsec, fromsym, tosec, tosym)) {
1610 report_sec_mismatch(modname, mismatch,
1611 fromsec, r->r_offset, fromsym,
1612 is_function(from), tosec, tosym,
1613 is_function(to));
1614 }
1615}
1616
1617static int is_executable_section(struct elf_info* elf, unsigned int section_index)
1618{
1619 if (section_index > elf->num_sections)
1620 fatal("section_index is outside elf->num_sections!\n");
1621
1622 return ((elf->sechdrs[section_index].sh_flags & SHF_EXECINSTR) == SHF_EXECINSTR);
1623}
1624
1625/*
1626 * We rely on a gross hack in section_rel[a]() calling find_extable_entry_size()
1627 * to know the sizeof(struct exception_table_entry) for the target architecture.
1628 */
1629static unsigned int extable_entry_size = 0;
1630static void find_extable_entry_size(const char* const sec, const Elf_Rela* r)
1631{
1632 /*
1633 * If we're currently checking the second relocation within __ex_table,
1634 * that relocation offset tells us the offsetof(struct
1635 * exception_table_entry, fixup) which is equal to sizeof(struct
1636 * exception_table_entry) divided by two. We use that to our advantage
1637 * since there's no portable way to get that size as every architecture
1638 * seems to go with different sized types. Not pretty but better than
1639 * hard-coding the size for every architecture..
1640 */
1641 if (!extable_entry_size)
1642 extable_entry_size = r->r_offset * 2;
1643}
1644
1645static inline bool is_extable_fault_address(Elf_Rela *r)
1646{
1647 /*
1648 * extable_entry_size is only discovered after we've handled the
1649 * _second_ relocation in __ex_table, so only abort when we're not
1650 * handling the first reloc and extable_entry_size is zero.
1651 */
1652 if (r->r_offset && extable_entry_size == 0)
1653 fatal("extable_entry size hasn't been discovered!\n");
1654
1655 return ((r->r_offset == 0) ||
1656 (r->r_offset % extable_entry_size == 0));
1657}
1658
1659#define is_second_extable_reloc(Start, Cur, Sec) \
1660 (((Cur) == (Start) + 1) && (strcmp("__ex_table", (Sec)) == 0))
1661
1662static void report_extable_warnings(const char* modname, struct elf_info* elf,
1663 const struct sectioncheck* const mismatch,
1664 Elf_Rela* r, Elf_Sym* sym,
1665 const char* fromsec, const char* tosec)
1666{
1667 Elf_Sym* fromsym = find_elf_symbol2(elf, r->r_offset, fromsec);
1668 const char* fromsym_name = sym_name(elf, fromsym);
1669 Elf_Sym* tosym = find_elf_symbol(elf, r->r_addend, sym);
1670 const char* tosym_name = sym_name(elf, tosym);
1671 const char* from_pretty_name;
1672 const char* from_pretty_name_p;
1673 const char* to_pretty_name;
1674 const char* to_pretty_name_p;
1675
1676 get_pretty_name(is_function(fromsym),
1677 &from_pretty_name, &from_pretty_name_p);
1678 get_pretty_name(is_function(tosym),
1679 &to_pretty_name, &to_pretty_name_p);
1680
1681 warn("%s(%s+0x%lx): Section mismatch in reference"
1682 " from the %s %s%s to the %s %s:%s%s\n",
1683 modname, fromsec, (long)r->r_offset, from_pretty_name,
1684 fromsym_name, from_pretty_name_p,
1685 to_pretty_name, tosec, tosym_name, to_pretty_name_p);
1686
1687 if (!match(tosec, mismatch->bad_tosec) &&
1688 is_executable_section(elf, get_secindex(elf, sym)))
1689 fprintf(stderr,
1690 "The relocation at %s+0x%lx references\n"
1691 "section \"%s\" which is not in the list of\n"
1692 "authorized sections. If you're adding a new section\n"
1693 "and/or if this reference is valid, add \"%s\" to the\n"
1694 "list of authorized sections to jump to on fault.\n"
1695 "This can be achieved by adding \"%s\" to \n"
1696 "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n",
1697 fromsec, (long)r->r_offset, tosec, tosec, tosec);
1698}
1699
1700static void extable_mismatch_handler(const char* modname, struct elf_info *elf,
1701 const struct sectioncheck* const mismatch,
1702 Elf_Rela* r, Elf_Sym* sym,
1703 const char *fromsec)
1704{
1705 const char* tosec = sec_name(elf, get_secindex(elf, sym));
1706
1707 sec_mismatch_count++;
1708
1709 report_extable_warnings(modname, elf, mismatch, r, sym, fromsec, tosec);
1710
1711 if (match(tosec, mismatch->bad_tosec))
1712 fatal("The relocation at %s+0x%lx references\n"
1713 "section \"%s\" which is black-listed.\n"
1714 "Something is seriously wrong and should be fixed.\n"
1715 "You might get more information about where this is\n"
1716 "coming from by using scripts/check_extable.sh %s\n",
1717 fromsec, (long)r->r_offset, tosec, modname);
1718 else if (!is_executable_section(elf, get_secindex(elf, sym))) {
1719 if (is_extable_fault_address(r))
1720 fatal("The relocation at %s+0x%lx references\n"
1721 "section \"%s\" which is not executable, IOW\n"
1722 "it is not possible for the kernel to fault\n"
1723 "at that address. Something is seriously wrong\n"
1724 "and should be fixed.\n",
1725 fromsec, (long)r->r_offset, tosec);
1726 else
1727 fatal("The relocation at %s+0x%lx references\n"
1728 "section \"%s\" which is not executable, IOW\n"
1729 "the kernel will fault if it ever tries to\n"
1730 "jump to it. Something is seriously wrong\n"
1731 "and should be fixed.\n",
1732 fromsec, (long)r->r_offset, tosec);
1733 }
1734}
1735
1736static void check_section_mismatch(const char *modname, struct elf_info *elf,
1737 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1738{
1739 const char *tosec = sec_name(elf, get_secindex(elf, sym));
1740 const struct sectioncheck *mismatch = section_mismatch(fromsec, tosec);
1741
1742 if (mismatch) {
1743 if (mismatch->handler)
1744 mismatch->handler(modname, elf, mismatch,
1745 r, sym, fromsec);
1746 else
1747 default_mismatch_handler(modname, elf, mismatch,
1748 r, sym, fromsec);
1749 }
1750}
1751
1752static unsigned int *reloc_location(struct elf_info *elf,
1753 Elf_Shdr *sechdr, Elf_Rela *r)
1754{
1755 return sym_get_data_by_offset(elf, sechdr->sh_info, r->r_offset);
1756}
1757
1758static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1759{
1760 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1761 unsigned int *location = reloc_location(elf, sechdr, r);
1762
1763 switch (r_typ) {
1764 case R_386_32:
1765 r->r_addend = TO_NATIVE(*location);
1766 break;
1767 case R_386_PC32:
1768 r->r_addend = TO_NATIVE(*location) + 4;
1769 /* For CONFIG_RELOCATABLE=y */
1770 if (elf->hdr->e_type == ET_EXEC)
1771 r->r_addend += r->r_offset;
1772 break;
1773 }
1774 return 0;
1775}
1776
1777#ifndef R_ARM_CALL
1778#define R_ARM_CALL 28
1779#endif
1780#ifndef R_ARM_JUMP24
1781#define R_ARM_JUMP24 29
1782#endif
1783
1784#ifndef R_ARM_THM_CALL
1785#define R_ARM_THM_CALL 10
1786#endif
1787#ifndef R_ARM_THM_JUMP24
1788#define R_ARM_THM_JUMP24 30
1789#endif
1790#ifndef R_ARM_THM_JUMP19
1791#define R_ARM_THM_JUMP19 51
1792#endif
1793
1794static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1795{
1796 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1797
1798 switch (r_typ) {
1799 case R_ARM_ABS32:
1800 /* From ARM ABI: (S + A) | T */
1801 r->r_addend = (int)(long)
1802 (elf->symtab_start + ELF_R_SYM(r->r_info));
1803 break;
1804 case R_ARM_PC24:
1805 case R_ARM_CALL:
1806 case R_ARM_JUMP24:
1807 case R_ARM_THM_CALL:
1808 case R_ARM_THM_JUMP24:
1809 case R_ARM_THM_JUMP19:
1810 /* From ARM ABI: ((S + A) | T) - P */
1811 r->r_addend = (int)(long)(elf->hdr +
1812 sechdr->sh_offset +
1813 (r->r_offset - sechdr->sh_addr));
1814 break;
1815 default:
1816 return 1;
1817 }
1818 return 0;
1819}
1820
1821static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1822{
1823 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1824 unsigned int *location = reloc_location(elf, sechdr, r);
1825 unsigned int inst;
1826
1827 if (r_typ == R_MIPS_HI16)
1828 return 1; /* skip this */
1829 inst = TO_NATIVE(*location);
1830 switch (r_typ) {
1831 case R_MIPS_LO16:
1832 r->r_addend = inst & 0xffff;
1833 break;
1834 case R_MIPS_26:
1835 r->r_addend = (inst & 0x03ffffff) << 2;
1836 break;
1837 case R_MIPS_32:
1838 r->r_addend = inst;
1839 break;
1840 }
1841 return 0;
1842}
1843
1844static void section_rela(const char *modname, struct elf_info *elf,
1845 Elf_Shdr *sechdr)
1846{
1847 Elf_Sym *sym;
1848 Elf_Rela *rela;
1849 Elf_Rela r;
1850 unsigned int r_sym;
1851 const char *fromsec;
1852
1853 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
1854 Elf_Rela *stop = (void *)start + sechdr->sh_size;
1855
1856 fromsec = sech_name(elf, sechdr);
1857 fromsec += strlen(".rela");
1858 /* if from section (name) is know good then skip it */
1859 if (match(fromsec, section_white_list))
1860 return;
1861
1862 for (rela = start; rela < stop; rela++) {
1863 r.r_offset = TO_NATIVE(rela->r_offset);
1864#if KERNEL_ELFCLASS == ELFCLASS64
1865 if (elf->hdr->e_machine == EM_MIPS) {
1866 unsigned int r_typ;
1867 r_sym = ELF64_MIPS_R_SYM(rela->r_info);
1868 r_sym = TO_NATIVE(r_sym);
1869 r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
1870 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1871 } else {
1872 r.r_info = TO_NATIVE(rela->r_info);
1873 r_sym = ELF_R_SYM(r.r_info);
1874 }
1875#else
1876 r.r_info = TO_NATIVE(rela->r_info);
1877 r_sym = ELF_R_SYM(r.r_info);
1878#endif
1879 r.r_addend = TO_NATIVE(rela->r_addend);
1880 sym = elf->symtab_start + r_sym;
1881 /* Skip special sections */
1882 if (is_shndx_special(sym->st_shndx))
1883 continue;
1884 if (is_second_extable_reloc(start, rela, fromsec))
1885 find_extable_entry_size(fromsec, &r);
1886 check_section_mismatch(modname, elf, &r, sym, fromsec);
1887 }
1888}
1889
1890static void section_rel(const char *modname, struct elf_info *elf,
1891 Elf_Shdr *sechdr)
1892{
1893 Elf_Sym *sym;
1894 Elf_Rel *rel;
1895 Elf_Rela r;
1896 unsigned int r_sym;
1897 const char *fromsec;
1898
1899 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
1900 Elf_Rel *stop = (void *)start + sechdr->sh_size;
1901
1902 fromsec = sech_name(elf, sechdr);
1903 fromsec += strlen(".rel");
1904 /* if from section (name) is know good then skip it */
1905 if (match(fromsec, section_white_list))
1906 return;
1907
1908 for (rel = start; rel < stop; rel++) {
1909 r.r_offset = TO_NATIVE(rel->r_offset);
1910#if KERNEL_ELFCLASS == ELFCLASS64
1911 if (elf->hdr->e_machine == EM_MIPS) {
1912 unsigned int r_typ;
1913 r_sym = ELF64_MIPS_R_SYM(rel->r_info);
1914 r_sym = TO_NATIVE(r_sym);
1915 r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
1916 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1917 } else {
1918 r.r_info = TO_NATIVE(rel->r_info);
1919 r_sym = ELF_R_SYM(r.r_info);
1920 }
1921#else
1922 r.r_info = TO_NATIVE(rel->r_info);
1923 r_sym = ELF_R_SYM(r.r_info);
1924#endif
1925 r.r_addend = 0;
1926 switch (elf->hdr->e_machine) {
1927 case EM_386:
1928 if (addend_386_rel(elf, sechdr, &r))
1929 continue;
1930 break;
1931 case EM_ARM:
1932 if (addend_arm_rel(elf, sechdr, &r))
1933 continue;
1934 break;
1935 case EM_MIPS:
1936 if (addend_mips_rel(elf, sechdr, &r))
1937 continue;
1938 break;
1939 }
1940 sym = elf->symtab_start + r_sym;
1941 /* Skip special sections */
1942 if (is_shndx_special(sym->st_shndx))
1943 continue;
1944 if (is_second_extable_reloc(start, rel, fromsec))
1945 find_extable_entry_size(fromsec, &r);
1946 check_section_mismatch(modname, elf, &r, sym, fromsec);
1947 }
1948}
1949
1950/**
1951 * A module includes a number of sections that are discarded
1952 * either when loaded or when used as built-in.
1953 * For loaded modules all functions marked __init and all data
1954 * marked __initdata will be discarded when the module has been initialized.
1955 * Likewise for modules used built-in the sections marked __exit
1956 * are discarded because __exit marked function are supposed to be called
1957 * only when a module is unloaded which never happens for built-in modules.
1958 * The check_sec_ref() function traverses all relocation records
1959 * to find all references to a section that reference a section that will
1960 * be discarded and warns about it.
1961 **/
1962static void check_sec_ref(struct module *mod, const char *modname,
1963 struct elf_info *elf)
1964{
1965 int i;
1966 Elf_Shdr *sechdrs = elf->sechdrs;
1967
1968 /* Walk through all sections */
1969 for (i = 0; i < elf->num_sections; i++) {
1970 check_section(modname, elf, &elf->sechdrs[i]);
1971 /* We want to process only relocation sections and not .init */
1972 if (sechdrs[i].sh_type == SHT_RELA)
1973 section_rela(modname, elf, &elf->sechdrs[i]);
1974 else if (sechdrs[i].sh_type == SHT_REL)
1975 section_rel(modname, elf, &elf->sechdrs[i]);
1976 }
1977}
1978
1979static char *remove_dot(char *s)
1980{
1981 size_t n = strcspn(s, ".");
1982
1983 if (n && s[n]) {
1984 size_t m = strspn(s + n + 1, "0123456789");
1985 if (m && (s[n + m] == '.' || s[n + m] == 0))
1986 s[n] = 0;
1987 }
1988 return s;
1989}
1990
1991static void read_symbols(const char *modname)
1992{
1993 const char *symname;
1994 char *version;
1995 char *license;
1996 char *namespace;
1997 struct module *mod;
1998 struct elf_info info = { };
1999 Elf_Sym *sym;
2000
2001 if (!parse_elf(&info, modname))
2002 return;
2003
2004 {
2005 char *tmp;
2006
2007 /* strip trailing .o */
2008 tmp = NOFAIL(strdup(modname));
2009 tmp[strlen(tmp) - 2] = '\0';
2010 mod = new_module(tmp);
2011 free(tmp);
2012 }
2013
2014 if (!mod->is_vmlinux) {
2015 license = get_modinfo(&info, "license");
2016 if (!license)
2017 warn("missing MODULE_LICENSE() in %s\n", modname);
2018 while (license) {
2019 if (license_is_gpl_compatible(license))
2020 mod->gpl_compatible = 1;
2021 else {
2022 mod->gpl_compatible = 0;
2023 break;
2024 }
2025 license = get_next_modinfo(&info, "license", license);
2026 }
2027
2028 namespace = get_modinfo(&info, "import_ns");
2029 while (namespace) {
2030 add_namespace(&mod->imported_namespaces, namespace);
2031 namespace = get_next_modinfo(&info, "import_ns",
2032 namespace);
2033 }
2034 }
2035
2036 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
2037 symname = remove_dot(info.strtab + sym->st_name);
2038
2039 handle_symbol(mod, &info, sym, symname);
2040 handle_moddevtable(mod, &info, sym, symname);
2041 }
2042
2043 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
2044 symname = remove_dot(info.strtab + sym->st_name);
2045
2046 /* Apply symbol namespaces from __kstrtabns_<symbol> entries. */
2047 if (strstarts(symname, "__kstrtabns_"))
2048 sym_update_namespace(symname + strlen("__kstrtabns_"),
2049 namespace_from_kstrtabns(&info,
2050 sym));
2051
2052 if (strstarts(symname, "__crc_"))
2053 handle_modversion(mod, &info, sym,
2054 symname + strlen("__crc_"));
2055 }
2056
2057 // check for static EXPORT_SYMBOL_* functions && global vars
2058 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
2059 unsigned char bind = ELF_ST_BIND(sym->st_info);
2060
2061 if (bind == STB_GLOBAL || bind == STB_WEAK) {
2062 struct symbol *s =
2063 find_symbol(remove_dot(info.strtab +
2064 sym->st_name));
2065
2066 if (s)
2067 s->is_static = 0;
2068 }
2069 }
2070
2071 check_sec_ref(mod, modname, &info);
2072
2073 if (!mod->is_vmlinux) {
2074 version = get_modinfo(&info, "version");
2075 if (version || all_versions)
2076 get_src_version(modname, mod->srcversion,
2077 sizeof(mod->srcversion) - 1);
2078 }
2079
2080 parse_elf_finish(&info);
2081
2082 /* Our trick to get versioning for module struct etc. - it's
2083 * never passed as an argument to an exported function, so
2084 * the automatic versioning doesn't pick it up, but it's really
2085 * important anyhow */
2086 if (modversions)
2087 mod->unres = alloc_symbol("module_layout", 0, mod->unres);
2088}
2089
2090static void read_symbols_from_files(const char *filename)
2091{
2092 FILE *in = stdin;
2093 char fname[PATH_MAX];
2094
2095 if (strcmp(filename, "-") != 0) {
2096 in = fopen(filename, "r");
2097 if (!in)
2098 fatal("Can't open filenames file %s: %m", filename);
2099 }
2100
2101 while (fgets(fname, PATH_MAX, in) != NULL) {
2102 if (strends(fname, "\n"))
2103 fname[strlen(fname)-1] = '\0';
2104 read_symbols(fname);
2105 }
2106
2107 if (in != stdin)
2108 fclose(in);
2109}
2110
2111#define SZ 500
2112
2113/* We first write the generated file into memory using the
2114 * following helper, then compare to the file on disk and
2115 * only update the later if anything changed */
2116
2117void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
2118 const char *fmt, ...)
2119{
2120 char tmp[SZ];
2121 int len;
2122 va_list ap;
2123
2124 va_start(ap, fmt);
2125 len = vsnprintf(tmp, SZ, fmt, ap);
2126 buf_write(buf, tmp, len);
2127 va_end(ap);
2128}
2129
2130void buf_write(struct buffer *buf, const char *s, int len)
2131{
2132 if (buf->size - buf->pos < len) {
2133 buf->size += len + SZ;
2134 buf->p = NOFAIL(realloc(buf->p, buf->size));
2135 }
2136 strncpy(buf->p + buf->pos, s, len);
2137 buf->pos += len;
2138}
2139
2140static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
2141{
2142 switch (exp) {
2143 case export_gpl:
2144 fatal("GPL-incompatible module %s.ko uses GPL-only symbol '%s'\n",
2145 m, s);
2146 break;
2147 case export_unused_gpl:
2148 fatal("GPL-incompatible module %s.ko uses GPL-only symbol marked UNUSED '%s'\n",
2149 m, s);
2150 break;
2151 case export_gpl_future:
2152 warn("GPL-incompatible module %s.ko uses future GPL-only symbol '%s'\n",
2153 m, s);
2154 break;
2155 case export_plain:
2156 case export_unused:
2157 case export_unknown:
2158 /* ignore */
2159 break;
2160 }
2161}
2162
2163static void check_for_unused(enum export exp, const char *m, const char *s)
2164{
2165 switch (exp) {
2166 case export_unused:
2167 case export_unused_gpl:
2168 warn("module %s.ko uses symbol '%s' marked UNUSED\n",
2169 m, s);
2170 break;
2171 default:
2172 /* ignore */
2173 break;
2174 }
2175}
2176
2177static int check_exports(struct module *mod)
2178{
2179 struct symbol *s, *exp;
2180 int err = 0;
2181
2182 for (s = mod->unres; s; s = s->next) {
2183 const char *basename;
2184 exp = find_symbol(s->name);
2185 if (!exp || exp->module == mod) {
2186 if (have_vmlinux && !s->weak) {
2187 modpost_log(warn_unresolved ? LOG_WARN : LOG_ERROR,
2188 "\"%s\" [%s.ko] undefined!\n",
2189 s->name, mod->name);
2190 if (!warn_unresolved)
2191 err = 1;
2192 }
2193 continue;
2194 }
2195 basename = strrchr(mod->name, '/');
2196 if (basename)
2197 basename++;
2198 else
2199 basename = mod->name;
2200
2201 if (exp->namespace &&
2202 !module_imports_namespace(mod, exp->namespace)) {
2203 modpost_log(allow_missing_ns_imports ? LOG_WARN : LOG_ERROR,
2204 "module %s uses symbol %s from namespace %s, but does not import it.\n",
2205 basename, exp->name, exp->namespace);
2206 if (!allow_missing_ns_imports)
2207 err = 1;
2208 add_namespace(&mod->missing_namespaces, exp->namespace);
2209 }
2210
2211 if (!mod->gpl_compatible)
2212 check_for_gpl_usage(exp->export, basename, exp->name);
2213 check_for_unused(exp->export, basename, exp->name);
2214 }
2215
2216 return err;
2217}
2218
2219static int check_modname_len(struct module *mod)
2220{
2221 const char *mod_name;
2222
2223 mod_name = strrchr(mod->name, '/');
2224 if (mod_name == NULL)
2225 mod_name = mod->name;
2226 else
2227 mod_name++;
2228 if (strlen(mod_name) >= MODULE_NAME_LEN) {
2229 merror("module name is too long [%s.ko]\n", mod->name);
2230 return 1;
2231 }
2232
2233 return 0;
2234}
2235
2236/**
2237 * Header for the generated file
2238 **/
2239static void add_header(struct buffer *b, struct module *mod)
2240{
2241 buf_printf(b, "#include <linux/module.h>\n");
2242 /*
2243 * Include build-salt.h after module.h in order to
2244 * inherit the definitions.
2245 */
2246 buf_printf(b, "#define INCLUDE_VERMAGIC\n");
2247 buf_printf(b, "#include <linux/build-salt.h>\n");
2248 buf_printf(b, "#include <linux/vermagic.h>\n");
2249 buf_printf(b, "#include <linux/compiler.h>\n");
2250 buf_printf(b, "\n");
2251 buf_printf(b, "BUILD_SALT;\n");
2252 buf_printf(b, "\n");
2253 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
2254 buf_printf(b, "MODULE_INFO(name, KBUILD_MODNAME);\n");
2255 buf_printf(b, "\n");
2256 buf_printf(b, "__visible struct module __this_module\n");
2257 buf_printf(b, "__section(.gnu.linkonce.this_module) = {\n");
2258 buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
2259 if (mod->has_init)
2260 buf_printf(b, "\t.init = init_module,\n");
2261 if (mod->has_cleanup)
2262 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
2263 "\t.exit = cleanup_module,\n"
2264 "#endif\n");
2265 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
2266 buf_printf(b, "};\n");
2267}
2268
2269static void add_intree_flag(struct buffer *b, int is_intree)
2270{
2271 if (is_intree)
2272 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
2273}
2274
2275/* Cannot check for assembler */
2276static void add_retpoline(struct buffer *b)
2277{
2278 buf_printf(b, "\n#ifdef CONFIG_RETPOLINE\n");
2279 buf_printf(b, "MODULE_INFO(retpoline, \"Y\");\n");
2280 buf_printf(b, "#endif\n");
2281}
2282
2283static void add_staging_flag(struct buffer *b, const char *name)
2284{
2285 if (strstarts(name, "drivers/staging"))
2286 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
2287}
2288
2289/**
2290 * Record CRCs for unresolved symbols
2291 **/
2292static int add_versions(struct buffer *b, struct module *mod)
2293{
2294 struct symbol *s, *exp;
2295 int err = 0;
2296
2297 for (s = mod->unres; s; s = s->next) {
2298 exp = find_symbol(s->name);
2299 if (!exp || exp->module == mod)
2300 continue;
2301 s->module = exp->module;
2302 s->crc_valid = exp->crc_valid;
2303 s->crc = exp->crc;
2304 }
2305
2306 if (!modversions)
2307 return err;
2308
2309 buf_printf(b, "\n");
2310 buf_printf(b, "static const struct modversion_info ____versions[]\n");
2311 buf_printf(b, "__used __section(__versions) = {\n");
2312
2313 for (s = mod->unres; s; s = s->next) {
2314 if (!s->module)
2315 continue;
2316 if (!s->crc_valid) {
2317 warn("\"%s\" [%s.ko] has no CRC!\n",
2318 s->name, mod->name);
2319 continue;
2320 }
2321 if (strlen(s->name) >= MODULE_NAME_LEN) {
2322 merror("too long symbol \"%s\" [%s.ko]\n",
2323 s->name, mod->name);
2324 err = 1;
2325 break;
2326 }
2327 buf_printf(b, "\t{ %#8x, \"%s\" },\n",
2328 s->crc, s->name);
2329 }
2330
2331 buf_printf(b, "};\n");
2332
2333 return err;
2334}
2335
2336static void add_depends(struct buffer *b, struct module *mod)
2337{
2338 struct symbol *s;
2339 int first = 1;
2340
2341 /* Clear ->seen flag of modules that own symbols needed by this. */
2342 for (s = mod->unres; s; s = s->next)
2343 if (s->module)
2344 s->module->seen = s->module->is_vmlinux;
2345
2346 buf_printf(b, "\n");
2347 buf_printf(b, "MODULE_INFO(depends, \"");
2348 for (s = mod->unres; s; s = s->next) {
2349 const char *p;
2350 if (!s->module)
2351 continue;
2352
2353 if (s->module->seen)
2354 continue;
2355
2356 s->module->seen = 1;
2357 p = strrchr(s->module->name, '/');
2358 if (p)
2359 p++;
2360 else
2361 p = s->module->name;
2362 buf_printf(b, "%s%s", first ? "" : ",", p);
2363 first = 0;
2364 }
2365 buf_printf(b, "\");\n");
2366}
2367
2368static void add_srcversion(struct buffer *b, struct module *mod)
2369{
2370 if (mod->srcversion[0]) {
2371 buf_printf(b, "\n");
2372 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
2373 mod->srcversion);
2374 }
2375}
2376
2377static void write_buf(struct buffer *b, const char *fname)
2378{
2379 FILE *file;
2380
2381 file = fopen(fname, "w");
2382 if (!file) {
2383 perror(fname);
2384 exit(1);
2385 }
2386 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
2387 perror(fname);
2388 exit(1);
2389 }
2390 if (fclose(file) != 0) {
2391 perror(fname);
2392 exit(1);
2393 }
2394}
2395
2396static void write_if_changed(struct buffer *b, const char *fname)
2397{
2398 char *tmp;
2399 FILE *file;
2400 struct stat st;
2401
2402 file = fopen(fname, "r");
2403 if (!file)
2404 goto write;
2405
2406 if (fstat(fileno(file), &st) < 0)
2407 goto close_write;
2408
2409 if (st.st_size != b->pos)
2410 goto close_write;
2411
2412 tmp = NOFAIL(malloc(b->pos));
2413 if (fread(tmp, 1, b->pos, file) != b->pos)
2414 goto free_write;
2415
2416 if (memcmp(tmp, b->p, b->pos) != 0)
2417 goto free_write;
2418
2419 free(tmp);
2420 fclose(file);
2421 return;
2422
2423 free_write:
2424 free(tmp);
2425 close_write:
2426 fclose(file);
2427 write:
2428 write_buf(b, fname);
2429}
2430
2431/* parse Module.symvers file. line format:
2432 * 0x12345678<tab>symbol<tab>module<tab>export<tab>namespace
2433 **/
2434static void read_dump(const char *fname)
2435{
2436 char *buf, *pos, *line;
2437
2438 buf = read_text_file(fname);
2439 if (!buf)
2440 /* No symbol versions, silently ignore */
2441 return;
2442
2443 pos = buf;
2444
2445 while ((line = get_line(&pos))) {
2446 char *symname, *namespace, *modname, *d, *export;
2447 unsigned int crc;
2448 struct module *mod;
2449 struct symbol *s;
2450
2451 if (!(symname = strchr(line, '\t')))
2452 goto fail;
2453 *symname++ = '\0';
2454 if (!(modname = strchr(symname, '\t')))
2455 goto fail;
2456 *modname++ = '\0';
2457 if (!(export = strchr(modname, '\t')))
2458 goto fail;
2459 *export++ = '\0';
2460 if (!(namespace = strchr(export, '\t')))
2461 goto fail;
2462 *namespace++ = '\0';
2463
2464 crc = strtoul(line, &d, 16);
2465 if (*symname == '\0' || *modname == '\0' || *d != '\0')
2466 goto fail;
2467 mod = find_module(modname);
2468 if (!mod) {
2469 mod = new_module(modname);
2470 mod->from_dump = 1;
2471 }
2472 s = sym_add_exported(symname, mod, export_no(export));
2473 s->is_static = 0;
2474 sym_set_crc(symname, crc);
2475 sym_update_namespace(symname, namespace);
2476 }
2477 free(buf);
2478 return;
2479fail:
2480 free(buf);
2481 fatal("parse error in symbol dump file\n");
2482}
2483
2484/* For normal builds always dump all symbols.
2485 * For external modules only dump symbols
2486 * that are not read from kernel Module.symvers.
2487 **/
2488static int dump_sym(struct symbol *sym)
2489{
2490 if (!external_module)
2491 return 1;
2492 if (sym->module->from_dump)
2493 return 0;
2494 return 1;
2495}
2496
2497static void write_dump(const char *fname)
2498{
2499 struct buffer buf = { };
2500 struct symbol *symbol;
2501 const char *namespace;
2502 int n;
2503
2504 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
2505 symbol = symbolhash[n];
2506 while (symbol) {
2507 if (dump_sym(symbol)) {
2508 namespace = symbol->namespace;
2509 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\t%s\n",
2510 symbol->crc, symbol->name,
2511 symbol->module->name,
2512 export_str(symbol->export),
2513 namespace ? namespace : "");
2514 }
2515 symbol = symbol->next;
2516 }
2517 }
2518 write_buf(&buf, fname);
2519 free(buf.p);
2520}
2521
2522static void write_namespace_deps_files(const char *fname)
2523{
2524 struct module *mod;
2525 struct namespace_list *ns;
2526 struct buffer ns_deps_buf = {};
2527
2528 for (mod = modules; mod; mod = mod->next) {
2529
2530 if (mod->from_dump || !mod->missing_namespaces)
2531 continue;
2532
2533 buf_printf(&ns_deps_buf, "%s.ko:", mod->name);
2534
2535 for (ns = mod->missing_namespaces; ns; ns = ns->next)
2536 buf_printf(&ns_deps_buf, " %s", ns->namespace);
2537
2538 buf_printf(&ns_deps_buf, "\n");
2539 }
2540
2541 write_if_changed(&ns_deps_buf, fname);
2542 free(ns_deps_buf.p);
2543}
2544
2545struct dump_list {
2546 struct dump_list *next;
2547 const char *file;
2548};
2549
2550int main(int argc, char **argv)
2551{
2552 struct module *mod;
2553 struct buffer buf = { };
2554 char *missing_namespace_deps = NULL;
2555 char *dump_write = NULL, *files_source = NULL;
2556 int opt;
2557 int err;
2558 int n;
2559 struct dump_list *dump_read_start = NULL;
2560 struct dump_list **dump_read_iter = &dump_read_start;
2561
2562 while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:")) != -1) {
2563 switch (opt) {
2564 case 'e':
2565 external_module = 1;
2566 break;
2567 case 'i':
2568 *dump_read_iter =
2569 NOFAIL(calloc(1, sizeof(**dump_read_iter)));
2570 (*dump_read_iter)->file = optarg;
2571 dump_read_iter = &(*dump_read_iter)->next;
2572 break;
2573 case 'm':
2574 modversions = 1;
2575 break;
2576 case 'n':
2577 ignore_missing_files = 1;
2578 break;
2579 case 'o':
2580 dump_write = optarg;
2581 break;
2582 case 'a':
2583 all_versions = 1;
2584 break;
2585 case 'T':
2586 files_source = optarg;
2587 break;
2588 case 'w':
2589 warn_unresolved = 1;
2590 break;
2591 case 'E':
2592 sec_mismatch_fatal = 1;
2593 break;
2594 case 'N':
2595 allow_missing_ns_imports = 1;
2596 break;
2597 case 'd':
2598 missing_namespace_deps = optarg;
2599 break;
2600 default:
2601 exit(1);
2602 }
2603 }
2604
2605 while (dump_read_start) {
2606 struct dump_list *tmp;
2607
2608 read_dump(dump_read_start->file);
2609 tmp = dump_read_start->next;
2610 free(dump_read_start);
2611 dump_read_start = tmp;
2612 }
2613
2614 while (optind < argc)
2615 read_symbols(argv[optind++]);
2616
2617 if (files_source)
2618 read_symbols_from_files(files_source);
2619
2620 /*
2621 * When there's no vmlinux, don't print warnings about
2622 * unresolved symbols (since there'll be too many ;)
2623 */
2624 if (!have_vmlinux)
2625 warn("Symbol info of vmlinux is missing. Unresolved symbol check will be entirely skipped.\n");
2626
2627 err = 0;
2628
2629 for (mod = modules; mod; mod = mod->next) {
2630 char fname[PATH_MAX];
2631
2632 if (mod->is_vmlinux || mod->from_dump)
2633 continue;
2634
2635 buf.pos = 0;
2636
2637 err |= check_modname_len(mod);
2638 err |= check_exports(mod);
2639
2640 add_header(&buf, mod);
2641 add_intree_flag(&buf, !external_module);
2642 add_retpoline(&buf);
2643 add_staging_flag(&buf, mod->name);
2644 err |= add_versions(&buf, mod);
2645 add_depends(&buf, mod);
2646 add_moddevtable(&buf, mod);
2647 add_srcversion(&buf, mod);
2648
2649 sprintf(fname, "%s.mod.c", mod->name);
2650 write_if_changed(&buf, fname);
2651 }
2652
2653 if (missing_namespace_deps)
2654 write_namespace_deps_files(missing_namespace_deps);
2655
2656 if (dump_write)
2657 write_dump(dump_write);
2658 if (sec_mismatch_count && sec_mismatch_fatal)
2659 fatal("Section mismatches detected.\n"
2660 "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n");
2661 for (n = 0; n < SYMBOL_HASH_SIZE; n++) {
2662 struct symbol *s;
2663
2664 for (s = symbolhash[n]; s; s = s->next) {
2665 if (s->is_static)
2666 warn("\"%s\" [%s] is a static %s\n",
2667 s->name, s->module->name,
2668 export_str(s->export));
2669 }
2670 }
2671
2672 free(buf.p);
2673
2674 return err;
2675}
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 error_occurred = true;
74 break;
75 default: /* invalid loglevel, ignore */
76 break;
77 }
78
79 fprintf(stderr, "modpost: ");
80
81 va_start(arglist, fmt);
82 vfprintf(stderr, fmt, arglist);
83 va_end(arglist);
84}
85
86static inline bool strends(const char *str, const char *postfix)
87{
88 if (strlen(str) < strlen(postfix))
89 return false;
90
91 return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0;
92}
93
94void *do_nofail(void *ptr, const char *expr)
95{
96 if (!ptr)
97 fatal("Memory allocation failure: %s.\n", expr);
98
99 return ptr;
100}
101
102char *read_text_file(const char *filename)
103{
104 struct stat st;
105 size_t nbytes;
106 int fd;
107 char *buf;
108
109 fd = open(filename, O_RDONLY);
110 if (fd < 0) {
111 perror(filename);
112 exit(1);
113 }
114
115 if (fstat(fd, &st) < 0) {
116 perror(filename);
117 exit(1);
118 }
119
120 buf = NOFAIL(malloc(st.st_size + 1));
121
122 nbytes = st.st_size;
123
124 while (nbytes) {
125 ssize_t bytes_read;
126
127 bytes_read = read(fd, buf, nbytes);
128 if (bytes_read < 0) {
129 perror(filename);
130 exit(1);
131 }
132
133 nbytes -= bytes_read;
134 }
135 buf[st.st_size] = '\0';
136
137 close(fd);
138
139 return buf;
140}
141
142char *get_line(char **stringp)
143{
144 char *orig = *stringp, *next;
145
146 /* do not return the unwanted extra line at EOF */
147 if (!orig || *orig == '\0')
148 return NULL;
149
150 /* don't use strsep here, it is not available everywhere */
151 next = strchr(orig, '\n');
152 if (next)
153 *next++ = '\0';
154
155 *stringp = next;
156
157 return orig;
158}
159
160/* A list of all modules we processed */
161LIST_HEAD(modules);
162
163static struct module *find_module(const char *modname)
164{
165 struct module *mod;
166
167 list_for_each_entry(mod, &modules, list) {
168 if (strcmp(mod->name, modname) == 0)
169 return mod;
170 }
171 return NULL;
172}
173
174static struct module *new_module(const char *name, size_t namelen)
175{
176 struct module *mod;
177
178 mod = NOFAIL(malloc(sizeof(*mod) + namelen + 1));
179 memset(mod, 0, sizeof(*mod));
180
181 INIT_LIST_HEAD(&mod->exported_symbols);
182 INIT_LIST_HEAD(&mod->unresolved_symbols);
183 INIT_LIST_HEAD(&mod->missing_namespaces);
184 INIT_LIST_HEAD(&mod->imported_namespaces);
185
186 memcpy(mod->name, name, namelen);
187 mod->name[namelen] = '\0';
188 mod->is_vmlinux = (strcmp(mod->name, "vmlinux") == 0);
189
190 /*
191 * Set mod->is_gpl_compatible to true by default. If MODULE_LICENSE()
192 * is missing, do not check the use for EXPORT_SYMBOL_GPL() becasue
193 * modpost will exit wiht error anyway.
194 */
195 mod->is_gpl_compatible = true;
196
197 list_add_tail(&mod->list, &modules);
198
199 return mod;
200}
201
202/* A hash of all exported symbols,
203 * struct symbol is also used for lists of unresolved symbols */
204
205#define SYMBOL_HASH_SIZE 1024
206
207struct symbol {
208 struct symbol *next;
209 struct list_head list; /* link to module::exported_symbols or module::unresolved_symbols */
210 struct module *module;
211 char *namespace;
212 unsigned int crc;
213 bool crc_valid;
214 bool weak;
215 bool is_func;
216 bool is_gpl_only; /* exported by EXPORT_SYMBOL_GPL */
217 bool used; /* there exists a user of this symbol */
218 char name[];
219};
220
221static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
222
223/* This is based on the hash algorithm from gdbm, via tdb */
224static inline unsigned int tdb_hash(const char *name)
225{
226 unsigned value; /* Used to compute the hash value. */
227 unsigned i; /* Used to cycle through random values. */
228
229 /* Set the initial value from the key size. */
230 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++)
231 value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
232
233 return (1103515243 * value + 12345);
234}
235
236/**
237 * Allocate a new symbols for use in the hash of exported symbols or
238 * the list of unresolved symbols per module
239 **/
240static struct symbol *alloc_symbol(const char *name)
241{
242 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
243
244 memset(s, 0, sizeof(*s));
245 strcpy(s->name, name);
246
247 return s;
248}
249
250/* For the hash of exported symbols */
251static void hash_add_symbol(struct symbol *sym)
252{
253 unsigned int hash;
254
255 hash = tdb_hash(sym->name) % SYMBOL_HASH_SIZE;
256 sym->next = symbolhash[hash];
257 symbolhash[hash] = sym;
258}
259
260static void sym_add_unresolved(const char *name, struct module *mod, bool weak)
261{
262 struct symbol *sym;
263
264 sym = alloc_symbol(name);
265 sym->weak = weak;
266
267 list_add_tail(&sym->list, &mod->unresolved_symbols);
268}
269
270static struct symbol *sym_find_with_module(const char *name, struct module *mod)
271{
272 struct symbol *s;
273
274 /* For our purposes, .foo matches foo. PPC64 needs this. */
275 if (name[0] == '.')
276 name++;
277
278 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
279 if (strcmp(s->name, name) == 0 && (!mod || s->module == mod))
280 return s;
281 }
282 return NULL;
283}
284
285static struct symbol *find_symbol(const char *name)
286{
287 return sym_find_with_module(name, NULL);
288}
289
290struct namespace_list {
291 struct list_head list;
292 char namespace[];
293};
294
295static bool contains_namespace(struct list_head *head, const char *namespace)
296{
297 struct namespace_list *list;
298
299 /*
300 * The default namespace is null string "", which is always implicitly
301 * contained.
302 */
303 if (!namespace[0])
304 return true;
305
306 list_for_each_entry(list, head, list) {
307 if (!strcmp(list->namespace, namespace))
308 return true;
309 }
310
311 return false;
312}
313
314static void add_namespace(struct list_head *head, const char *namespace)
315{
316 struct namespace_list *ns_entry;
317
318 if (!contains_namespace(head, namespace)) {
319 ns_entry = NOFAIL(malloc(sizeof(*ns_entry) +
320 strlen(namespace) + 1));
321 strcpy(ns_entry->namespace, namespace);
322 list_add_tail(&ns_entry->list, head);
323 }
324}
325
326static void *sym_get_data_by_offset(const struct elf_info *info,
327 unsigned int secindex, unsigned long offset)
328{
329 Elf_Shdr *sechdr = &info->sechdrs[secindex];
330
331 return (void *)info->hdr + sechdr->sh_offset + offset;
332}
333
334void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym)
335{
336 return sym_get_data_by_offset(info, get_secindex(info, sym),
337 sym->st_value);
338}
339
340static const char *sech_name(const struct elf_info *info, Elf_Shdr *sechdr)
341{
342 return sym_get_data_by_offset(info, info->secindex_strings,
343 sechdr->sh_name);
344}
345
346static const char *sec_name(const struct elf_info *info, unsigned int secindex)
347{
348 /*
349 * If sym->st_shndx is a special section index, there is no
350 * corresponding section header.
351 * Return "" if the index is out of range of info->sechdrs[] array.
352 */
353 if (secindex >= info->num_sections)
354 return "";
355
356 return sech_name(info, &info->sechdrs[secindex]);
357}
358
359#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
360
361static struct symbol *sym_add_exported(const char *name, struct module *mod,
362 bool gpl_only, const char *namespace)
363{
364 struct symbol *s = find_symbol(name);
365
366 if (s && (!external_module || s->module->is_vmlinux || s->module == mod)) {
367 error("%s: '%s' exported twice. Previous export was in %s%s\n",
368 mod->name, name, s->module->name,
369 s->module->is_vmlinux ? "" : ".ko");
370 }
371
372 s = alloc_symbol(name);
373 s->module = mod;
374 s->is_gpl_only = gpl_only;
375 s->namespace = NOFAIL(strdup(namespace));
376 list_add_tail(&s->list, &mod->exported_symbols);
377 hash_add_symbol(s);
378
379 return s;
380}
381
382static void sym_set_crc(struct symbol *sym, unsigned int crc)
383{
384 sym->crc = crc;
385 sym->crc_valid = true;
386}
387
388static void *grab_file(const char *filename, size_t *size)
389{
390 struct stat st;
391 void *map = MAP_FAILED;
392 int fd;
393
394 fd = open(filename, O_RDONLY);
395 if (fd < 0)
396 return NULL;
397 if (fstat(fd, &st))
398 goto failed;
399
400 *size = st.st_size;
401 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
402
403failed:
404 close(fd);
405 if (map == MAP_FAILED)
406 return NULL;
407 return map;
408}
409
410static void release_file(void *file, size_t size)
411{
412 munmap(file, size);
413}
414
415static int parse_elf(struct elf_info *info, const char *filename)
416{
417 unsigned int i;
418 Elf_Ehdr *hdr;
419 Elf_Shdr *sechdrs;
420 Elf_Sym *sym;
421 const char *secstrings;
422 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
423
424 hdr = grab_file(filename, &info->size);
425 if (!hdr) {
426 if (ignore_missing_files) {
427 fprintf(stderr, "%s: %s (ignored)\n", filename,
428 strerror(errno));
429 return 0;
430 }
431 perror(filename);
432 exit(1);
433 }
434 info->hdr = hdr;
435 if (info->size < sizeof(*hdr)) {
436 /* file too small, assume this is an empty .o file */
437 return 0;
438 }
439 /* Is this a valid ELF file? */
440 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
441 (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
442 (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
443 (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
444 /* Not an ELF file - silently ignore it */
445 return 0;
446 }
447 /* Fix endianness in ELF header */
448 hdr->e_type = TO_NATIVE(hdr->e_type);
449 hdr->e_machine = TO_NATIVE(hdr->e_machine);
450 hdr->e_version = TO_NATIVE(hdr->e_version);
451 hdr->e_entry = TO_NATIVE(hdr->e_entry);
452 hdr->e_phoff = TO_NATIVE(hdr->e_phoff);
453 hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
454 hdr->e_flags = TO_NATIVE(hdr->e_flags);
455 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize);
456 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
457 hdr->e_phnum = TO_NATIVE(hdr->e_phnum);
458 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
459 hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
460 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
461 sechdrs = (void *)hdr + hdr->e_shoff;
462 info->sechdrs = sechdrs;
463
464 /* modpost only works for relocatable objects */
465 if (hdr->e_type != ET_REL)
466 fatal("%s: not relocatable object.", filename);
467
468 /* Check if file offset is correct */
469 if (hdr->e_shoff > info->size)
470 fatal("section header offset=%lu in file '%s' is bigger than filesize=%zu\n",
471 (unsigned long)hdr->e_shoff, filename, info->size);
472
473 if (hdr->e_shnum == SHN_UNDEF) {
474 /*
475 * There are more than 64k sections,
476 * read count from .sh_size.
477 */
478 info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
479 }
480 else {
481 info->num_sections = hdr->e_shnum;
482 }
483 if (hdr->e_shstrndx == SHN_XINDEX) {
484 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
485 }
486 else {
487 info->secindex_strings = hdr->e_shstrndx;
488 }
489
490 /* Fix endianness in section headers */
491 for (i = 0; i < info->num_sections; i++) {
492 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
493 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
494 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
495 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
496 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
497 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
498 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
499 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
500 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
501 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
502 }
503 /* Find symbol table. */
504 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
505 for (i = 1; i < info->num_sections; i++) {
506 const char *secname;
507 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
508
509 if (!nobits && sechdrs[i].sh_offset > info->size)
510 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > sizeof(*hrd)=%zu\n",
511 filename, (unsigned long)sechdrs[i].sh_offset,
512 sizeof(*hdr));
513
514 secname = secstrings + sechdrs[i].sh_name;
515 if (strcmp(secname, ".modinfo") == 0) {
516 if (nobits)
517 fatal("%s has NOBITS .modinfo\n", filename);
518 info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
519 info->modinfo_len = sechdrs[i].sh_size;
520 } else if (!strcmp(secname, ".export_symbol")) {
521 info->export_symbol_secndx = i;
522 }
523
524 if (sechdrs[i].sh_type == SHT_SYMTAB) {
525 unsigned int sh_link_idx;
526 symtab_idx = i;
527 info->symtab_start = (void *)hdr +
528 sechdrs[i].sh_offset;
529 info->symtab_stop = (void *)hdr +
530 sechdrs[i].sh_offset + sechdrs[i].sh_size;
531 sh_link_idx = sechdrs[i].sh_link;
532 info->strtab = (void *)hdr +
533 sechdrs[sh_link_idx].sh_offset;
534 }
535
536 /* 32bit section no. table? ("more than 64k sections") */
537 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
538 symtab_shndx_idx = i;
539 info->symtab_shndx_start = (void *)hdr +
540 sechdrs[i].sh_offset;
541 info->symtab_shndx_stop = (void *)hdr +
542 sechdrs[i].sh_offset + sechdrs[i].sh_size;
543 }
544 }
545 if (!info->symtab_start)
546 fatal("%s has no symtab?\n", filename);
547
548 /* Fix endianness in symbols */
549 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
550 sym->st_shndx = TO_NATIVE(sym->st_shndx);
551 sym->st_name = TO_NATIVE(sym->st_name);
552 sym->st_value = TO_NATIVE(sym->st_value);
553 sym->st_size = TO_NATIVE(sym->st_size);
554 }
555
556 if (symtab_shndx_idx != ~0U) {
557 Elf32_Word *p;
558 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
559 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
560 filename, sechdrs[symtab_shndx_idx].sh_link,
561 symtab_idx);
562 /* Fix endianness */
563 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
564 p++)
565 *p = TO_NATIVE(*p);
566 }
567
568 symsearch_init(info);
569
570 return 1;
571}
572
573static void parse_elf_finish(struct elf_info *info)
574{
575 symsearch_finish(info);
576 release_file(info->hdr, info->size);
577}
578
579static int ignore_undef_symbol(struct elf_info *info, const char *symname)
580{
581 /* ignore __this_module, it will be resolved shortly */
582 if (strcmp(symname, "__this_module") == 0)
583 return 1;
584 /* ignore global offset table */
585 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
586 return 1;
587 if (info->hdr->e_machine == EM_PPC)
588 /* Special register function linked on all modules during final link of .ko */
589 if (strstarts(symname, "_restgpr_") ||
590 strstarts(symname, "_savegpr_") ||
591 strstarts(symname, "_rest32gpr_") ||
592 strstarts(symname, "_save32gpr_") ||
593 strstarts(symname, "_restvr_") ||
594 strstarts(symname, "_savevr_"))
595 return 1;
596 if (info->hdr->e_machine == EM_PPC64)
597 /* Special register function linked on all modules during final link of .ko */
598 if (strstarts(symname, "_restgpr0_") ||
599 strstarts(symname, "_savegpr0_") ||
600 strstarts(symname, "_restvr_") ||
601 strstarts(symname, "_savevr_") ||
602 strcmp(symname, ".TOC.") == 0)
603 return 1;
604
605 if (info->hdr->e_machine == EM_S390)
606 /* Expoline thunks are linked on all kernel modules during final link of .ko */
607 if (strstarts(symname, "__s390_indirect_jump_r"))
608 return 1;
609 /* Do not ignore this symbol */
610 return 0;
611}
612
613static void handle_symbol(struct module *mod, struct elf_info *info,
614 const Elf_Sym *sym, const char *symname)
615{
616 switch (sym->st_shndx) {
617 case SHN_COMMON:
618 if (strstarts(symname, "__gnu_lto_")) {
619 /* Should warn here, but modpost runs before the linker */
620 } else
621 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
622 break;
623 case SHN_UNDEF:
624 /* undefined symbol */
625 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
626 ELF_ST_BIND(sym->st_info) != STB_WEAK)
627 break;
628 if (ignore_undef_symbol(info, symname))
629 break;
630 if (info->hdr->e_machine == EM_SPARC ||
631 info->hdr->e_machine == EM_SPARCV9) {
632 /* Ignore register directives. */
633 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
634 break;
635 if (symname[0] == '.') {
636 char *munged = NOFAIL(strdup(symname));
637 munged[0] = '_';
638 munged[1] = toupper(munged[1]);
639 symname = munged;
640 }
641 }
642
643 sym_add_unresolved(symname, mod,
644 ELF_ST_BIND(sym->st_info) == STB_WEAK);
645 break;
646 default:
647 if (strcmp(symname, "init_module") == 0)
648 mod->has_init = true;
649 if (strcmp(symname, "cleanup_module") == 0)
650 mod->has_cleanup = true;
651 break;
652 }
653}
654
655/**
656 * Parse tag=value strings from .modinfo section
657 **/
658static char *next_string(char *string, unsigned long *secsize)
659{
660 /* Skip non-zero chars */
661 while (string[0]) {
662 string++;
663 if ((*secsize)-- <= 1)
664 return NULL;
665 }
666
667 /* Skip any zero padding. */
668 while (!string[0]) {
669 string++;
670 if ((*secsize)-- <= 1)
671 return NULL;
672 }
673 return string;
674}
675
676static char *get_next_modinfo(struct elf_info *info, const char *tag,
677 char *prev)
678{
679 char *p;
680 unsigned int taglen = strlen(tag);
681 char *modinfo = info->modinfo;
682 unsigned long size = info->modinfo_len;
683
684 if (prev) {
685 size -= prev - modinfo;
686 modinfo = next_string(prev, &size);
687 }
688
689 for (p = modinfo; p; p = next_string(p, &size)) {
690 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
691 return p + taglen + 1;
692 }
693 return NULL;
694}
695
696static char *get_modinfo(struct elf_info *info, const char *tag)
697
698{
699 return get_next_modinfo(info, tag, NULL);
700}
701
702static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
703{
704 if (sym)
705 return elf->strtab + sym->st_name;
706 else
707 return "(unknown)";
708}
709
710/*
711 * Check whether the 'string' argument matches one of the 'patterns',
712 * an array of shell wildcard patterns (glob).
713 *
714 * Return true is there is a match.
715 */
716static bool match(const char *string, const char *const patterns[])
717{
718 const char *pattern;
719
720 while ((pattern = *patterns++)) {
721 if (!fnmatch(pattern, string, 0))
722 return true;
723 }
724
725 return false;
726}
727
728/* useful to pass patterns to match() directly */
729#define PATTERNS(...) \
730 ({ \
731 static const char *const patterns[] = {__VA_ARGS__, NULL}; \
732 patterns; \
733 })
734
735/* sections that we do not want to do full section mismatch check on */
736static const char *const section_white_list[] =
737{
738 ".comment*",
739 ".debug*",
740 ".zdebug*", /* Compressed debug sections. */
741 ".GCC.command.line", /* record-gcc-switches */
742 ".mdebug*", /* alpha, score, mips etc. */
743 ".pdr", /* alpha, score, mips etc. */
744 ".stab*",
745 ".note*",
746 ".got*",
747 ".toc*",
748 ".xt.prop", /* xtensa */
749 ".xt.lit", /* xtensa */
750 ".arcextmap*", /* arc */
751 ".gnu.linkonce.arcext*", /* arc : modules */
752 ".cmem*", /* EZchip */
753 ".fmt_slot*", /* EZchip */
754 ".gnu.lto*",
755 ".discard.*",
756 ".llvm.call-graph-profile", /* call graph */
757 NULL
758};
759
760/*
761 * This is used to find sections missing the SHF_ALLOC flag.
762 * The cause of this is often a section specified in assembler
763 * without "ax" / "aw".
764 */
765static void check_section(const char *modname, struct elf_info *elf,
766 Elf_Shdr *sechdr)
767{
768 const char *sec = sech_name(elf, sechdr);
769
770 if (sechdr->sh_type == SHT_PROGBITS &&
771 !(sechdr->sh_flags & SHF_ALLOC) &&
772 !match(sec, section_white_list)) {
773 warn("%s (%s): unexpected non-allocatable section.\n"
774 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
775 "Note that for example <linux/init.h> contains\n"
776 "section definitions for use in .S files.\n\n",
777 modname, sec);
778 }
779}
780
781
782
783#define ALL_INIT_DATA_SECTIONS \
784 ".init.setup", ".init.rodata", ".meminit.rodata", \
785 ".init.data", ".meminit.data"
786
787#define ALL_PCI_INIT_SECTIONS \
788 ".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \
789 ".pci_fixup_enable", ".pci_fixup_resume", \
790 ".pci_fixup_resume_early", ".pci_fixup_suspend"
791
792#define ALL_XXXINIT_SECTIONS ".meminit.*"
793
794#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
795#define ALL_EXIT_SECTIONS ".exit.*"
796
797#define DATA_SECTIONS ".data", ".data.rel"
798#define TEXT_SECTIONS ".text", ".text.*", ".sched.text", \
799 ".kprobes.text", ".cpuidle.text", ".noinstr.text", \
800 ".ltext", ".ltext.*"
801#define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \
802 ".fixup", ".entry.text", ".exception.text", \
803 ".coldtext", ".softirqentry.text"
804
805#define INIT_SECTIONS ".init.*"
806
807#define ALL_TEXT_SECTIONS ".init.text", ".meminit.text", ".exit.text", \
808 TEXT_SECTIONS, OTHER_TEXT_SECTIONS
809
810enum mismatch {
811 TEXTDATA_TO_ANY_INIT_EXIT,
812 XXXINIT_TO_SOME_INIT,
813 ANY_INIT_TO_ANY_EXIT,
814 ANY_EXIT_TO_ANY_INIT,
815 EXTABLE_TO_NON_TEXT,
816};
817
818/**
819 * Describe how to match sections on different criteria:
820 *
821 * @fromsec: Array of sections to be matched.
822 *
823 * @bad_tosec: Relocations applied to a section in @fromsec to a section in
824 * this array is forbidden (black-list). Can be empty.
825 *
826 * @good_tosec: Relocations applied to a section in @fromsec must be
827 * targeting sections in this array (white-list). Can be empty.
828 *
829 * @mismatch: Type of mismatch.
830 */
831struct sectioncheck {
832 const char *fromsec[20];
833 const char *bad_tosec[20];
834 const char *good_tosec[20];
835 enum mismatch mismatch;
836};
837
838static const struct sectioncheck sectioncheck[] = {
839/* Do not reference init/exit code/data from
840 * normal code and data
841 */
842{
843 .fromsec = { TEXT_SECTIONS, DATA_SECTIONS, NULL },
844 .bad_tosec = { ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL },
845 .mismatch = TEXTDATA_TO_ANY_INIT_EXIT,
846},
847/* Do not reference init code/data from meminit code/data */
848{
849 .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
850 .bad_tosec = { INIT_SECTIONS, NULL },
851 .mismatch = XXXINIT_TO_SOME_INIT,
852},
853/* Do not use exit code/data from init code */
854{
855 .fromsec = { ALL_INIT_SECTIONS, NULL },
856 .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
857 .mismatch = ANY_INIT_TO_ANY_EXIT,
858},
859/* Do not use init code/data from exit code */
860{
861 .fromsec = { ALL_EXIT_SECTIONS, NULL },
862 .bad_tosec = { ALL_INIT_SECTIONS, NULL },
863 .mismatch = ANY_EXIT_TO_ANY_INIT,
864},
865{
866 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
867 .bad_tosec = { INIT_SECTIONS, NULL },
868 .mismatch = ANY_INIT_TO_ANY_EXIT,
869},
870{
871 .fromsec = { "__ex_table", NULL },
872 /* If you're adding any new black-listed sections in here, consider
873 * adding a special 'printer' for them in scripts/check_extable.
874 */
875 .bad_tosec = { ".altinstr_replacement", NULL },
876 .good_tosec = {ALL_TEXT_SECTIONS , NULL},
877 .mismatch = EXTABLE_TO_NON_TEXT,
878}
879};
880
881static const struct sectioncheck *section_mismatch(
882 const char *fromsec, const char *tosec)
883{
884 int i;
885
886 /*
887 * The target section could be the SHT_NUL section when we're
888 * handling relocations to un-resolved symbols, trying to match it
889 * doesn't make much sense and causes build failures on parisc
890 * architectures.
891 */
892 if (*tosec == '\0')
893 return NULL;
894
895 for (i = 0; i < ARRAY_SIZE(sectioncheck); i++) {
896 const struct sectioncheck *check = §ioncheck[i];
897
898 if (match(fromsec, check->fromsec)) {
899 if (check->bad_tosec[0] && match(tosec, check->bad_tosec))
900 return check;
901 if (check->good_tosec[0] && !match(tosec, check->good_tosec))
902 return check;
903 }
904 }
905 return NULL;
906}
907
908/**
909 * Whitelist to allow certain references to pass with no warning.
910 *
911 * Pattern 1:
912 * If a module parameter is declared __initdata and permissions=0
913 * then this is legal despite the warning generated.
914 * We cannot see value of permissions here, so just ignore
915 * this pattern.
916 * The pattern is identified by:
917 * tosec = .init.data
918 * fromsec = .data*
919 * atsym =__param*
920 *
921 * Pattern 1a:
922 * module_param_call() ops can refer to __init set function if permissions=0
923 * The pattern is identified by:
924 * tosec = .init.text
925 * fromsec = .data*
926 * atsym = __param_ops_*
927 *
928 * Pattern 3:
929 * Whitelist all references from .head.text to any init section
930 *
931 * Pattern 4:
932 * Some symbols belong to init section but still it is ok to reference
933 * these from non-init sections as these symbols don't have any memory
934 * allocated for them and symbol address and value are same. So even
935 * if init section is freed, its ok to reference those symbols.
936 * For ex. symbols marking the init section boundaries.
937 * This pattern is identified by
938 * refsymname = __init_begin, _sinittext, _einittext
939 *
940 * Pattern 5:
941 * GCC may optimize static inlines when fed constant arg(s) resulting
942 * in functions like cpumask_empty() -- generating an associated symbol
943 * cpumask_empty.constprop.3 that appears in the audit. If the const that
944 * is passed in comes from __init, like say nmi_ipi_mask, we get a
945 * meaningless section warning. May need to add isra symbols too...
946 * This pattern is identified by
947 * tosec = init section
948 * fromsec = text section
949 * refsymname = *.constprop.*
950 *
951 **/
952static int secref_whitelist(const char *fromsec, const char *fromsym,
953 const char *tosec, const char *tosym)
954{
955 /* Check for pattern 1 */
956 if (match(tosec, PATTERNS(ALL_INIT_DATA_SECTIONS)) &&
957 match(fromsec, PATTERNS(DATA_SECTIONS)) &&
958 strstarts(fromsym, "__param"))
959 return 0;
960
961 /* Check for pattern 1a */
962 if (strcmp(tosec, ".init.text") == 0 &&
963 match(fromsec, PATTERNS(DATA_SECTIONS)) &&
964 strstarts(fromsym, "__param_ops_"))
965 return 0;
966
967 /* symbols in data sections that may refer to any init/exit sections */
968 if (match(fromsec, PATTERNS(DATA_SECTIONS)) &&
969 match(tosec, PATTERNS(ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS)) &&
970 match(fromsym, PATTERNS("*_ops", "*_probe", "*_console")))
971 return 0;
972
973 /*
974 * symbols in data sections must not refer to .exit.*, but there are
975 * quite a few offenders, so hide these unless for W=1 builds until
976 * these are fixed.
977 */
978 if (!extra_warn &&
979 match(fromsec, PATTERNS(DATA_SECTIONS)) &&
980 match(tosec, PATTERNS(ALL_EXIT_SECTIONS)) &&
981 match(fromsym, PATTERNS("*driver")))
982 return 0;
983
984 /* Check for pattern 3 */
985 if (strstarts(fromsec, ".head.text") &&
986 match(tosec, PATTERNS(ALL_INIT_SECTIONS)))
987 return 0;
988
989 /* Check for pattern 4 */
990 if (match(tosym, PATTERNS("__init_begin", "_sinittext", "_einittext")))
991 return 0;
992
993 /* Check for pattern 5 */
994 if (match(fromsec, PATTERNS(ALL_TEXT_SECTIONS)) &&
995 match(tosec, PATTERNS(ALL_INIT_SECTIONS)) &&
996 match(fromsym, PATTERNS("*.constprop.*")))
997 return 0;
998
999 return 1;
1000}
1001
1002static Elf_Sym *find_fromsym(struct elf_info *elf, Elf_Addr addr,
1003 unsigned int secndx)
1004{
1005 return symsearch_find_nearest(elf, addr, secndx, false, ~0);
1006}
1007
1008static Elf_Sym *find_tosym(struct elf_info *elf, Elf_Addr addr, Elf_Sym *sym)
1009{
1010 /* If the supplied symbol has a valid name, return it */
1011 if (is_valid_name(elf, sym))
1012 return sym;
1013
1014 /*
1015 * Strive to find a better symbol name, but the resulting name may not
1016 * match the symbol referenced in the original code.
1017 */
1018 return symsearch_find_nearest(elf, addr, get_secindex(elf, sym),
1019 true, 20);
1020}
1021
1022static bool is_executable_section(struct elf_info *elf, unsigned int secndx)
1023{
1024 if (secndx >= elf->num_sections)
1025 return false;
1026
1027 return (elf->sechdrs[secndx].sh_flags & SHF_EXECINSTR) != 0;
1028}
1029
1030static void default_mismatch_handler(const char *modname, struct elf_info *elf,
1031 const struct sectioncheck* const mismatch,
1032 Elf_Sym *tsym,
1033 unsigned int fsecndx, const char *fromsec, Elf_Addr faddr,
1034 const char *tosec, Elf_Addr taddr)
1035{
1036 Elf_Sym *from;
1037 const char *tosym;
1038 const char *fromsym;
1039
1040 from = find_fromsym(elf, faddr, fsecndx);
1041 fromsym = sym_name(elf, from);
1042
1043 tsym = find_tosym(elf, taddr, tsym);
1044 tosym = sym_name(elf, tsym);
1045
1046 /* check whitelist - we may ignore it */
1047 if (!secref_whitelist(fromsec, fromsym, tosec, tosym))
1048 return;
1049
1050 sec_mismatch_count++;
1051
1052 warn("%s: section mismatch in reference: %s+0x%x (section: %s) -> %s (section: %s)\n",
1053 modname, fromsym, (unsigned int)(faddr - from->st_value), fromsec, tosym, tosec);
1054
1055 if (mismatch->mismatch == EXTABLE_TO_NON_TEXT) {
1056 if (match(tosec, mismatch->bad_tosec))
1057 fatal("The relocation at %s+0x%lx references\n"
1058 "section \"%s\" which is black-listed.\n"
1059 "Something is seriously wrong and should be fixed.\n"
1060 "You might get more information about where this is\n"
1061 "coming from by using scripts/check_extable.sh %s\n",
1062 fromsec, (long)faddr, tosec, modname);
1063 else if (is_executable_section(elf, get_secindex(elf, tsym)))
1064 warn("The relocation at %s+0x%lx references\n"
1065 "section \"%s\" which is not in the list of\n"
1066 "authorized sections. If you're adding a new section\n"
1067 "and/or if this reference is valid, add \"%s\" to the\n"
1068 "list of authorized sections to jump to on fault.\n"
1069 "This can be achieved by adding \"%s\" to\n"
1070 "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n",
1071 fromsec, (long)faddr, tosec, tosec, tosec);
1072 else
1073 error("%s+0x%lx references non-executable section '%s'\n",
1074 fromsec, (long)faddr, tosec);
1075 }
1076}
1077
1078static void check_export_symbol(struct module *mod, struct elf_info *elf,
1079 Elf_Addr faddr, const char *secname,
1080 Elf_Sym *sym)
1081{
1082 static const char *prefix = "__export_symbol_";
1083 const char *label_name, *name, *data;
1084 Elf_Sym *label;
1085 struct symbol *s;
1086 bool is_gpl;
1087
1088 label = find_fromsym(elf, faddr, elf->export_symbol_secndx);
1089 label_name = sym_name(elf, label);
1090
1091 if (!strstarts(label_name, prefix)) {
1092 error("%s: .export_symbol section contains strange symbol '%s'\n",
1093 mod->name, label_name);
1094 return;
1095 }
1096
1097 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
1098 ELF_ST_BIND(sym->st_info) != STB_WEAK) {
1099 error("%s: local symbol '%s' was exported\n", mod->name,
1100 label_name + strlen(prefix));
1101 return;
1102 }
1103
1104 name = sym_name(elf, sym);
1105 if (strcmp(label_name + strlen(prefix), name)) {
1106 error("%s: .export_symbol section references '%s', but it does not seem to be an export symbol\n",
1107 mod->name, name);
1108 return;
1109 }
1110
1111 data = sym_get_data(elf, label); /* license */
1112 if (!strcmp(data, "GPL")) {
1113 is_gpl = true;
1114 } else if (!strcmp(data, "")) {
1115 is_gpl = false;
1116 } else {
1117 error("%s: unknown license '%s' was specified for '%s'\n",
1118 mod->name, data, name);
1119 return;
1120 }
1121
1122 data += strlen(data) + 1; /* namespace */
1123 s = sym_add_exported(name, mod, is_gpl, data);
1124
1125 /*
1126 * We need to be aware whether we are exporting a function or
1127 * a data on some architectures.
1128 */
1129 s->is_func = (ELF_ST_TYPE(sym->st_info) == STT_FUNC);
1130
1131 /*
1132 * For parisc64, symbols prefixed $$ from the library have the symbol type
1133 * STT_LOPROC. They should be handled as functions too.
1134 */
1135 if (elf->hdr->e_ident[EI_CLASS] == ELFCLASS64 &&
1136 elf->hdr->e_machine == EM_PARISC &&
1137 ELF_ST_TYPE(sym->st_info) == STT_LOPROC)
1138 s->is_func = true;
1139
1140 if (match(secname, PATTERNS(ALL_INIT_SECTIONS)))
1141 warn("%s: %s: EXPORT_SYMBOL used for init symbol. Remove __init or EXPORT_SYMBOL.\n",
1142 mod->name, name);
1143 else if (match(secname, PATTERNS(ALL_EXIT_SECTIONS)))
1144 warn("%s: %s: EXPORT_SYMBOL used for exit symbol. Remove __exit or EXPORT_SYMBOL.\n",
1145 mod->name, name);
1146}
1147
1148static void check_section_mismatch(struct module *mod, struct elf_info *elf,
1149 Elf_Sym *sym,
1150 unsigned int fsecndx, const char *fromsec,
1151 Elf_Addr faddr, Elf_Addr taddr)
1152{
1153 const char *tosec = sec_name(elf, get_secindex(elf, sym));
1154 const struct sectioncheck *mismatch;
1155
1156 if (module_enabled && elf->export_symbol_secndx == fsecndx) {
1157 check_export_symbol(mod, elf, faddr, tosec, sym);
1158 return;
1159 }
1160
1161 mismatch = section_mismatch(fromsec, tosec);
1162 if (!mismatch)
1163 return;
1164
1165 default_mismatch_handler(mod->name, elf, mismatch, sym,
1166 fsecndx, fromsec, faddr,
1167 tosec, taddr);
1168}
1169
1170static Elf_Addr addend_386_rel(uint32_t *location, unsigned int r_type)
1171{
1172 switch (r_type) {
1173 case R_386_32:
1174 return TO_NATIVE(*location);
1175 case R_386_PC32:
1176 return TO_NATIVE(*location) + 4;
1177 }
1178
1179 return (Elf_Addr)(-1);
1180}
1181
1182#ifndef R_ARM_CALL
1183#define R_ARM_CALL 28
1184#endif
1185#ifndef R_ARM_JUMP24
1186#define R_ARM_JUMP24 29
1187#endif
1188
1189#ifndef R_ARM_THM_CALL
1190#define R_ARM_THM_CALL 10
1191#endif
1192#ifndef R_ARM_THM_JUMP24
1193#define R_ARM_THM_JUMP24 30
1194#endif
1195
1196#ifndef R_ARM_MOVW_ABS_NC
1197#define R_ARM_MOVW_ABS_NC 43
1198#endif
1199
1200#ifndef R_ARM_MOVT_ABS
1201#define R_ARM_MOVT_ABS 44
1202#endif
1203
1204#ifndef R_ARM_THM_MOVW_ABS_NC
1205#define R_ARM_THM_MOVW_ABS_NC 47
1206#endif
1207
1208#ifndef R_ARM_THM_MOVT_ABS
1209#define R_ARM_THM_MOVT_ABS 48
1210#endif
1211
1212#ifndef R_ARM_THM_JUMP19
1213#define R_ARM_THM_JUMP19 51
1214#endif
1215
1216static int32_t sign_extend32(int32_t value, int index)
1217{
1218 uint8_t shift = 31 - index;
1219
1220 return (int32_t)(value << shift) >> shift;
1221}
1222
1223static Elf_Addr addend_arm_rel(void *loc, Elf_Sym *sym, unsigned int r_type)
1224{
1225 uint32_t inst, upper, lower, sign, j1, j2;
1226 int32_t offset;
1227
1228 switch (r_type) {
1229 case R_ARM_ABS32:
1230 case R_ARM_REL32:
1231 inst = TO_NATIVE(*(uint32_t *)loc);
1232 return inst + sym->st_value;
1233 case R_ARM_MOVW_ABS_NC:
1234 case R_ARM_MOVT_ABS:
1235 inst = TO_NATIVE(*(uint32_t *)loc);
1236 offset = sign_extend32(((inst & 0xf0000) >> 4) | (inst & 0xfff),
1237 15);
1238 return offset + sym->st_value;
1239 case R_ARM_PC24:
1240 case R_ARM_CALL:
1241 case R_ARM_JUMP24:
1242 inst = TO_NATIVE(*(uint32_t *)loc);
1243 offset = sign_extend32((inst & 0x00ffffff) << 2, 25);
1244 return offset + sym->st_value + 8;
1245 case R_ARM_THM_MOVW_ABS_NC:
1246 case R_ARM_THM_MOVT_ABS:
1247 upper = TO_NATIVE(*(uint16_t *)loc);
1248 lower = TO_NATIVE(*((uint16_t *)loc + 1));
1249 offset = sign_extend32(((upper & 0x000f) << 12) |
1250 ((upper & 0x0400) << 1) |
1251 ((lower & 0x7000) >> 4) |
1252 (lower & 0x00ff),
1253 15);
1254 return offset + sym->st_value;
1255 case R_ARM_THM_JUMP19:
1256 /*
1257 * Encoding T3:
1258 * S = upper[10]
1259 * imm6 = upper[5:0]
1260 * J1 = lower[13]
1261 * J2 = lower[11]
1262 * imm11 = lower[10:0]
1263 * imm32 = SignExtend(S:J2:J1:imm6:imm11:'0')
1264 */
1265 upper = TO_NATIVE(*(uint16_t *)loc);
1266 lower = TO_NATIVE(*((uint16_t *)loc + 1));
1267
1268 sign = (upper >> 10) & 1;
1269 j1 = (lower >> 13) & 1;
1270 j2 = (lower >> 11) & 1;
1271 offset = sign_extend32((sign << 20) | (j2 << 19) | (j1 << 18) |
1272 ((upper & 0x03f) << 12) |
1273 ((lower & 0x07ff) << 1),
1274 20);
1275 return offset + sym->st_value + 4;
1276 case R_ARM_THM_CALL:
1277 case R_ARM_THM_JUMP24:
1278 /*
1279 * Encoding T4:
1280 * S = upper[10]
1281 * imm10 = upper[9:0]
1282 * J1 = lower[13]
1283 * J2 = lower[11]
1284 * imm11 = lower[10:0]
1285 * I1 = NOT(J1 XOR S)
1286 * I2 = NOT(J2 XOR S)
1287 * imm32 = SignExtend(S:I1:I2:imm10:imm11:'0')
1288 */
1289 upper = TO_NATIVE(*(uint16_t *)loc);
1290 lower = TO_NATIVE(*((uint16_t *)loc + 1));
1291
1292 sign = (upper >> 10) & 1;
1293 j1 = (lower >> 13) & 1;
1294 j2 = (lower >> 11) & 1;
1295 offset = sign_extend32((sign << 24) |
1296 ((~(j1 ^ sign) & 1) << 23) |
1297 ((~(j2 ^ sign) & 1) << 22) |
1298 ((upper & 0x03ff) << 12) |
1299 ((lower & 0x07ff) << 1),
1300 24);
1301 return offset + sym->st_value + 4;
1302 }
1303
1304 return (Elf_Addr)(-1);
1305}
1306
1307static Elf_Addr addend_mips_rel(uint32_t *location, unsigned int r_type)
1308{
1309 uint32_t inst;
1310
1311 inst = TO_NATIVE(*location);
1312 switch (r_type) {
1313 case R_MIPS_LO16:
1314 return inst & 0xffff;
1315 case R_MIPS_26:
1316 return (inst & 0x03ffffff) << 2;
1317 case R_MIPS_32:
1318 return inst;
1319 }
1320 return (Elf_Addr)(-1);
1321}
1322
1323#ifndef EM_RISCV
1324#define EM_RISCV 243
1325#endif
1326
1327#ifndef R_RISCV_SUB32
1328#define R_RISCV_SUB32 39
1329#endif
1330
1331#ifndef EM_LOONGARCH
1332#define EM_LOONGARCH 258
1333#endif
1334
1335#ifndef R_LARCH_SUB32
1336#define R_LARCH_SUB32 55
1337#endif
1338
1339#ifndef R_LARCH_RELAX
1340#define R_LARCH_RELAX 100
1341#endif
1342
1343#ifndef R_LARCH_ALIGN
1344#define R_LARCH_ALIGN 102
1345#endif
1346
1347static void get_rel_type_and_sym(struct elf_info *elf, uint64_t r_info,
1348 unsigned int *r_type, unsigned int *r_sym)
1349{
1350 typedef struct {
1351 Elf64_Word r_sym; /* Symbol index */
1352 unsigned char r_ssym; /* Special symbol for 2nd relocation */
1353 unsigned char r_type3; /* 3rd relocation type */
1354 unsigned char r_type2; /* 2nd relocation type */
1355 unsigned char r_type; /* 1st relocation type */
1356 } Elf64_Mips_R_Info;
1357
1358 bool is_64bit = (elf->hdr->e_ident[EI_CLASS] == ELFCLASS64);
1359
1360 if (elf->hdr->e_machine == EM_MIPS && is_64bit) {
1361 Elf64_Mips_R_Info *mips64_r_info = (void *)&r_info;
1362
1363 *r_type = mips64_r_info->r_type;
1364 *r_sym = TO_NATIVE(mips64_r_info->r_sym);
1365 return;
1366 }
1367
1368 if (is_64bit)
1369 r_info = TO_NATIVE((Elf64_Xword)r_info);
1370 else
1371 r_info = TO_NATIVE((Elf32_Word)r_info);
1372
1373 *r_type = ELF_R_TYPE(r_info);
1374 *r_sym = ELF_R_SYM(r_info);
1375}
1376
1377static void section_rela(struct module *mod, struct elf_info *elf,
1378 unsigned int fsecndx, const char *fromsec,
1379 const Elf_Rela *start, const Elf_Rela *stop)
1380{
1381 const Elf_Rela *rela;
1382
1383 for (rela = start; rela < stop; rela++) {
1384 Elf_Sym *tsym;
1385 Elf_Addr taddr, r_offset;
1386 unsigned int r_type, r_sym;
1387
1388 r_offset = TO_NATIVE(rela->r_offset);
1389 get_rel_type_and_sym(elf, rela->r_info, &r_type, &r_sym);
1390
1391 tsym = elf->symtab_start + r_sym;
1392 taddr = tsym->st_value + TO_NATIVE(rela->r_addend);
1393
1394 switch (elf->hdr->e_machine) {
1395 case EM_RISCV:
1396 if (!strcmp("__ex_table", fromsec) &&
1397 r_type == R_RISCV_SUB32)
1398 continue;
1399 break;
1400 case EM_LOONGARCH:
1401 switch (r_type) {
1402 case R_LARCH_SUB32:
1403 if (!strcmp("__ex_table", fromsec))
1404 continue;
1405 break;
1406 case R_LARCH_RELAX:
1407 case R_LARCH_ALIGN:
1408 /* These relocs do not refer to symbols */
1409 continue;
1410 }
1411 break;
1412 }
1413
1414 check_section_mismatch(mod, elf, tsym,
1415 fsecndx, fromsec, r_offset, taddr);
1416 }
1417}
1418
1419static void section_rel(struct module *mod, struct elf_info *elf,
1420 unsigned int fsecndx, const char *fromsec,
1421 const Elf_Rel *start, const Elf_Rel *stop)
1422{
1423 const Elf_Rel *rel;
1424
1425 for (rel = start; rel < stop; rel++) {
1426 Elf_Sym *tsym;
1427 Elf_Addr taddr, r_offset;
1428 unsigned int r_type, r_sym;
1429 void *loc;
1430
1431 r_offset = TO_NATIVE(rel->r_offset);
1432 get_rel_type_and_sym(elf, rel->r_info, &r_type, &r_sym);
1433
1434 loc = sym_get_data_by_offset(elf, fsecndx, r_offset);
1435 tsym = elf->symtab_start + r_sym;
1436
1437 switch (elf->hdr->e_machine) {
1438 case EM_386:
1439 taddr = addend_386_rel(loc, r_type);
1440 break;
1441 case EM_ARM:
1442 taddr = addend_arm_rel(loc, tsym, r_type);
1443 break;
1444 case EM_MIPS:
1445 taddr = addend_mips_rel(loc, r_type);
1446 break;
1447 default:
1448 fatal("Please add code to calculate addend for this architecture\n");
1449 }
1450
1451 check_section_mismatch(mod, elf, tsym,
1452 fsecndx, fromsec, r_offset, taddr);
1453 }
1454}
1455
1456/**
1457 * A module includes a number of sections that are discarded
1458 * either when loaded or when used as built-in.
1459 * For loaded modules all functions marked __init and all data
1460 * marked __initdata will be discarded when the module has been initialized.
1461 * Likewise for modules used built-in the sections marked __exit
1462 * are discarded because __exit marked function are supposed to be called
1463 * only when a module is unloaded which never happens for built-in modules.
1464 * The check_sec_ref() function traverses all relocation records
1465 * to find all references to a section that reference a section that will
1466 * be discarded and warns about it.
1467 **/
1468static void check_sec_ref(struct module *mod, struct elf_info *elf)
1469{
1470 int i;
1471
1472 /* Walk through all sections */
1473 for (i = 0; i < elf->num_sections; i++) {
1474 Elf_Shdr *sechdr = &elf->sechdrs[i];
1475
1476 check_section(mod->name, elf, sechdr);
1477 /* We want to process only relocation sections and not .init */
1478 if (sechdr->sh_type == SHT_REL || sechdr->sh_type == SHT_RELA) {
1479 /* section to which the relocation applies */
1480 unsigned int secndx = sechdr->sh_info;
1481 const char *secname = sec_name(elf, secndx);
1482 const void *start, *stop;
1483
1484 /* If the section is known good, skip it */
1485 if (match(secname, section_white_list))
1486 continue;
1487
1488 start = sym_get_data_by_offset(elf, i, 0);
1489 stop = start + sechdr->sh_size;
1490
1491 if (sechdr->sh_type == SHT_RELA)
1492 section_rela(mod, elf, secndx, secname,
1493 start, stop);
1494 else
1495 section_rel(mod, elf, secndx, secname,
1496 start, stop);
1497 }
1498 }
1499}
1500
1501static char *remove_dot(char *s)
1502{
1503 size_t n = strcspn(s, ".");
1504
1505 if (n && s[n]) {
1506 size_t m = strspn(s + n + 1, "0123456789");
1507 if (m && (s[n + m + 1] == '.' || s[n + m + 1] == 0))
1508 s[n] = 0;
1509 }
1510 return s;
1511}
1512
1513/*
1514 * The CRCs are recorded in .*.cmd files in the form of:
1515 * #SYMVER <name> <crc>
1516 */
1517static void extract_crcs_for_object(const char *object, struct module *mod)
1518{
1519 char cmd_file[PATH_MAX];
1520 char *buf, *p;
1521 const char *base;
1522 int dirlen, ret;
1523
1524 base = strrchr(object, '/');
1525 if (base) {
1526 base++;
1527 dirlen = base - object;
1528 } else {
1529 dirlen = 0;
1530 base = object;
1531 }
1532
1533 ret = snprintf(cmd_file, sizeof(cmd_file), "%.*s.%s.cmd",
1534 dirlen, object, base);
1535 if (ret >= sizeof(cmd_file)) {
1536 error("%s: too long path was truncated\n", cmd_file);
1537 return;
1538 }
1539
1540 buf = read_text_file(cmd_file);
1541 p = buf;
1542
1543 while ((p = strstr(p, "\n#SYMVER "))) {
1544 char *name;
1545 size_t namelen;
1546 unsigned int crc;
1547 struct symbol *sym;
1548
1549 name = p + strlen("\n#SYMVER ");
1550
1551 p = strchr(name, ' ');
1552 if (!p)
1553 break;
1554
1555 namelen = p - name;
1556 p++;
1557
1558 if (!isdigit(*p))
1559 continue; /* skip this line */
1560
1561 crc = strtoul(p, &p, 0);
1562 if (*p != '\n')
1563 continue; /* skip this line */
1564
1565 name[namelen] = '\0';
1566
1567 /*
1568 * sym_find_with_module() may return NULL here.
1569 * It typically occurs when CONFIG_TRIM_UNUSED_KSYMS=y.
1570 * Since commit e1327a127703, genksyms calculates CRCs of all
1571 * symbols, including trimmed ones. Ignore orphan CRCs.
1572 */
1573 sym = sym_find_with_module(name, mod);
1574 if (sym)
1575 sym_set_crc(sym, crc);
1576 }
1577
1578 free(buf);
1579}
1580
1581/*
1582 * The symbol versions (CRC) are recorded in the .*.cmd files.
1583 * Parse them to retrieve CRCs for the current module.
1584 */
1585static void mod_set_crcs(struct module *mod)
1586{
1587 char objlist[PATH_MAX];
1588 char *buf, *p, *obj;
1589 int ret;
1590
1591 if (mod->is_vmlinux) {
1592 strcpy(objlist, ".vmlinux.objs");
1593 } else {
1594 /* objects for a module are listed in the *.mod file. */
1595 ret = snprintf(objlist, sizeof(objlist), "%s.mod", mod->name);
1596 if (ret >= sizeof(objlist)) {
1597 error("%s: too long path was truncated\n", objlist);
1598 return;
1599 }
1600 }
1601
1602 buf = read_text_file(objlist);
1603 p = buf;
1604
1605 while ((obj = strsep(&p, "\n")) && obj[0])
1606 extract_crcs_for_object(obj, mod);
1607
1608 free(buf);
1609}
1610
1611static void read_symbols(const char *modname)
1612{
1613 const char *symname;
1614 char *version;
1615 char *license;
1616 char *namespace;
1617 struct module *mod;
1618 struct elf_info info = { };
1619 Elf_Sym *sym;
1620
1621 if (!parse_elf(&info, modname))
1622 return;
1623
1624 if (!strends(modname, ".o")) {
1625 error("%s: filename must be suffixed with .o\n", modname);
1626 return;
1627 }
1628
1629 /* strip trailing .o */
1630 mod = new_module(modname, strlen(modname) - strlen(".o"));
1631
1632 if (!mod->is_vmlinux) {
1633 license = get_modinfo(&info, "license");
1634 if (!license)
1635 error("missing MODULE_LICENSE() in %s\n", modname);
1636 while (license) {
1637 if (!license_is_gpl_compatible(license)) {
1638 mod->is_gpl_compatible = false;
1639 break;
1640 }
1641 license = get_next_modinfo(&info, "license", license);
1642 }
1643
1644 namespace = get_modinfo(&info, "import_ns");
1645 while (namespace) {
1646 add_namespace(&mod->imported_namespaces, namespace);
1647 namespace = get_next_modinfo(&info, "import_ns",
1648 namespace);
1649 }
1650 }
1651
1652 if (extra_warn && !get_modinfo(&info, "description"))
1653 warn("missing MODULE_DESCRIPTION() in %s\n", modname);
1654 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
1655 symname = remove_dot(info.strtab + sym->st_name);
1656
1657 handle_symbol(mod, &info, sym, symname);
1658 handle_moddevtable(mod, &info, sym, symname);
1659 }
1660
1661 check_sec_ref(mod, &info);
1662
1663 if (!mod->is_vmlinux) {
1664 version = get_modinfo(&info, "version");
1665 if (version || all_versions)
1666 get_src_version(mod->name, mod->srcversion,
1667 sizeof(mod->srcversion) - 1);
1668 }
1669
1670 parse_elf_finish(&info);
1671
1672 if (modversions) {
1673 /*
1674 * Our trick to get versioning for module struct etc. - it's
1675 * never passed as an argument to an exported function, so
1676 * the automatic versioning doesn't pick it up, but it's really
1677 * important anyhow.
1678 */
1679 sym_add_unresolved("module_layout", mod, false);
1680
1681 mod_set_crcs(mod);
1682 }
1683}
1684
1685static void read_symbols_from_files(const char *filename)
1686{
1687 FILE *in = stdin;
1688 char fname[PATH_MAX];
1689
1690 in = fopen(filename, "r");
1691 if (!in)
1692 fatal("Can't open filenames file %s: %m", filename);
1693
1694 while (fgets(fname, PATH_MAX, in) != NULL) {
1695 if (strends(fname, "\n"))
1696 fname[strlen(fname)-1] = '\0';
1697 read_symbols(fname);
1698 }
1699
1700 fclose(in);
1701}
1702
1703#define SZ 500
1704
1705/* We first write the generated file into memory using the
1706 * following helper, then compare to the file on disk and
1707 * only update the later if anything changed */
1708
1709void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
1710 const char *fmt, ...)
1711{
1712 char tmp[SZ];
1713 int len;
1714 va_list ap;
1715
1716 va_start(ap, fmt);
1717 len = vsnprintf(tmp, SZ, fmt, ap);
1718 buf_write(buf, tmp, len);
1719 va_end(ap);
1720}
1721
1722void buf_write(struct buffer *buf, const char *s, int len)
1723{
1724 if (buf->size - buf->pos < len) {
1725 buf->size += len + SZ;
1726 buf->p = NOFAIL(realloc(buf->p, buf->size));
1727 }
1728 strncpy(buf->p + buf->pos, s, len);
1729 buf->pos += len;
1730}
1731
1732static void check_exports(struct module *mod)
1733{
1734 struct symbol *s, *exp;
1735
1736 list_for_each_entry(s, &mod->unresolved_symbols, list) {
1737 const char *basename;
1738 exp = find_symbol(s->name);
1739 if (!exp) {
1740 if (!s->weak && nr_unresolved++ < MAX_UNRESOLVED_REPORTS)
1741 modpost_log(warn_unresolved ? LOG_WARN : LOG_ERROR,
1742 "\"%s\" [%s.ko] undefined!\n",
1743 s->name, mod->name);
1744 continue;
1745 }
1746 if (exp->module == mod) {
1747 error("\"%s\" [%s.ko] was exported without definition\n",
1748 s->name, mod->name);
1749 continue;
1750 }
1751
1752 exp->used = true;
1753 s->module = exp->module;
1754 s->crc_valid = exp->crc_valid;
1755 s->crc = exp->crc;
1756
1757 basename = strrchr(mod->name, '/');
1758 if (basename)
1759 basename++;
1760 else
1761 basename = mod->name;
1762
1763 if (!contains_namespace(&mod->imported_namespaces, exp->namespace)) {
1764 modpost_log(allow_missing_ns_imports ? LOG_WARN : LOG_ERROR,
1765 "module %s uses symbol %s from namespace %s, but does not import it.\n",
1766 basename, exp->name, exp->namespace);
1767 add_namespace(&mod->missing_namespaces, exp->namespace);
1768 }
1769
1770 if (!mod->is_gpl_compatible && exp->is_gpl_only)
1771 error("GPL-incompatible module %s.ko uses GPL-only symbol '%s'\n",
1772 basename, exp->name);
1773 }
1774}
1775
1776static void handle_white_list_exports(const char *white_list)
1777{
1778 char *buf, *p, *name;
1779
1780 buf = read_text_file(white_list);
1781 p = buf;
1782
1783 while ((name = strsep(&p, "\n"))) {
1784 struct symbol *sym = find_symbol(name);
1785
1786 if (sym)
1787 sym->used = true;
1788 }
1789
1790 free(buf);
1791}
1792
1793static void check_modname_len(struct module *mod)
1794{
1795 const char *mod_name;
1796
1797 mod_name = strrchr(mod->name, '/');
1798 if (mod_name == NULL)
1799 mod_name = mod->name;
1800 else
1801 mod_name++;
1802 if (strlen(mod_name) >= MODULE_NAME_LEN)
1803 error("module name is too long [%s.ko]\n", mod->name);
1804}
1805
1806/**
1807 * Header for the generated file
1808 **/
1809static void add_header(struct buffer *b, struct module *mod)
1810{
1811 buf_printf(b, "#include <linux/module.h>\n");
1812 /*
1813 * Include build-salt.h after module.h in order to
1814 * inherit the definitions.
1815 */
1816 buf_printf(b, "#define INCLUDE_VERMAGIC\n");
1817 buf_printf(b, "#include <linux/build-salt.h>\n");
1818 buf_printf(b, "#include <linux/elfnote-lto.h>\n");
1819 buf_printf(b, "#include <linux/export-internal.h>\n");
1820 buf_printf(b, "#include <linux/vermagic.h>\n");
1821 buf_printf(b, "#include <linux/compiler.h>\n");
1822 buf_printf(b, "\n");
1823 buf_printf(b, "#ifdef CONFIG_UNWINDER_ORC\n");
1824 buf_printf(b, "#include <asm/orc_header.h>\n");
1825 buf_printf(b, "ORC_HEADER;\n");
1826 buf_printf(b, "#endif\n");
1827 buf_printf(b, "\n");
1828 buf_printf(b, "BUILD_SALT;\n");
1829 buf_printf(b, "BUILD_LTO_INFO;\n");
1830 buf_printf(b, "\n");
1831 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1832 buf_printf(b, "MODULE_INFO(name, KBUILD_MODNAME);\n");
1833 buf_printf(b, "\n");
1834 buf_printf(b, "__visible struct module __this_module\n");
1835 buf_printf(b, "__section(\".gnu.linkonce.this_module\") = {\n");
1836 buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
1837 if (mod->has_init)
1838 buf_printf(b, "\t.init = init_module,\n");
1839 if (mod->has_cleanup)
1840 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
1841 "\t.exit = cleanup_module,\n"
1842 "#endif\n");
1843 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
1844 buf_printf(b, "};\n");
1845
1846 if (!external_module)
1847 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
1848
1849 buf_printf(b,
1850 "\n"
1851 "#ifdef CONFIG_RETPOLINE\n"
1852 "MODULE_INFO(retpoline, \"Y\");\n"
1853 "#endif\n");
1854
1855 if (strstarts(mod->name, "drivers/staging"))
1856 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
1857
1858 if (strstarts(mod->name, "tools/testing"))
1859 buf_printf(b, "\nMODULE_INFO(test, \"Y\");\n");
1860}
1861
1862static void add_exported_symbols(struct buffer *buf, struct module *mod)
1863{
1864 struct symbol *sym;
1865
1866 /* generate struct for exported symbols */
1867 buf_printf(buf, "\n");
1868 list_for_each_entry(sym, &mod->exported_symbols, list) {
1869 if (trim_unused_exports && !sym->used)
1870 continue;
1871
1872 buf_printf(buf, "KSYMTAB_%s(%s, \"%s\", \"%s\");\n",
1873 sym->is_func ? "FUNC" : "DATA", sym->name,
1874 sym->is_gpl_only ? "_gpl" : "", sym->namespace);
1875 }
1876
1877 if (!modversions)
1878 return;
1879
1880 /* record CRCs for exported symbols */
1881 buf_printf(buf, "\n");
1882 list_for_each_entry(sym, &mod->exported_symbols, list) {
1883 if (trim_unused_exports && !sym->used)
1884 continue;
1885
1886 if (!sym->crc_valid)
1887 warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n"
1888 "Is \"%s\" prototyped in <asm/asm-prototypes.h>?\n",
1889 sym->name, mod->name, mod->is_vmlinux ? "" : ".ko",
1890 sym->name);
1891
1892 buf_printf(buf, "SYMBOL_CRC(%s, 0x%08x, \"%s\");\n",
1893 sym->name, sym->crc, sym->is_gpl_only ? "_gpl" : "");
1894 }
1895}
1896
1897/**
1898 * Record CRCs for unresolved symbols
1899 **/
1900static void add_versions(struct buffer *b, struct module *mod)
1901{
1902 struct symbol *s;
1903
1904 if (!modversions)
1905 return;
1906
1907 buf_printf(b, "\n");
1908 buf_printf(b, "static const struct modversion_info ____versions[]\n");
1909 buf_printf(b, "__used __section(\"__versions\") = {\n");
1910
1911 list_for_each_entry(s, &mod->unresolved_symbols, list) {
1912 if (!s->module)
1913 continue;
1914 if (!s->crc_valid) {
1915 warn("\"%s\" [%s.ko] has no CRC!\n",
1916 s->name, mod->name);
1917 continue;
1918 }
1919 if (strlen(s->name) >= MODULE_NAME_LEN) {
1920 error("too long symbol \"%s\" [%s.ko]\n",
1921 s->name, mod->name);
1922 break;
1923 }
1924 buf_printf(b, "\t{ %#8x, \"%s\" },\n",
1925 s->crc, s->name);
1926 }
1927
1928 buf_printf(b, "};\n");
1929}
1930
1931static void add_depends(struct buffer *b, struct module *mod)
1932{
1933 struct symbol *s;
1934 int first = 1;
1935
1936 /* Clear ->seen flag of modules that own symbols needed by this. */
1937 list_for_each_entry(s, &mod->unresolved_symbols, list) {
1938 if (s->module)
1939 s->module->seen = s->module->is_vmlinux;
1940 }
1941
1942 buf_printf(b, "\n");
1943 buf_printf(b, "MODULE_INFO(depends, \"");
1944 list_for_each_entry(s, &mod->unresolved_symbols, list) {
1945 const char *p;
1946 if (!s->module)
1947 continue;
1948
1949 if (s->module->seen)
1950 continue;
1951
1952 s->module->seen = true;
1953 p = strrchr(s->module->name, '/');
1954 if (p)
1955 p++;
1956 else
1957 p = s->module->name;
1958 buf_printf(b, "%s%s", first ? "" : ",", p);
1959 first = 0;
1960 }
1961 buf_printf(b, "\");\n");
1962}
1963
1964static void add_srcversion(struct buffer *b, struct module *mod)
1965{
1966 if (mod->srcversion[0]) {
1967 buf_printf(b, "\n");
1968 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
1969 mod->srcversion);
1970 }
1971}
1972
1973static void write_buf(struct buffer *b, const char *fname)
1974{
1975 FILE *file;
1976
1977 if (error_occurred)
1978 return;
1979
1980 file = fopen(fname, "w");
1981 if (!file) {
1982 perror(fname);
1983 exit(1);
1984 }
1985 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
1986 perror(fname);
1987 exit(1);
1988 }
1989 if (fclose(file) != 0) {
1990 perror(fname);
1991 exit(1);
1992 }
1993}
1994
1995static void write_if_changed(struct buffer *b, const char *fname)
1996{
1997 char *tmp;
1998 FILE *file;
1999 struct stat st;
2000
2001 file = fopen(fname, "r");
2002 if (!file)
2003 goto write;
2004
2005 if (fstat(fileno(file), &st) < 0)
2006 goto close_write;
2007
2008 if (st.st_size != b->pos)
2009 goto close_write;
2010
2011 tmp = NOFAIL(malloc(b->pos));
2012 if (fread(tmp, 1, b->pos, file) != b->pos)
2013 goto free_write;
2014
2015 if (memcmp(tmp, b->p, b->pos) != 0)
2016 goto free_write;
2017
2018 free(tmp);
2019 fclose(file);
2020 return;
2021
2022 free_write:
2023 free(tmp);
2024 close_write:
2025 fclose(file);
2026 write:
2027 write_buf(b, fname);
2028}
2029
2030static void write_vmlinux_export_c_file(struct module *mod)
2031{
2032 struct buffer buf = { };
2033
2034 buf_printf(&buf,
2035 "#include <linux/export-internal.h>\n");
2036
2037 add_exported_symbols(&buf, mod);
2038 write_if_changed(&buf, ".vmlinux.export.c");
2039 free(buf.p);
2040}
2041
2042/* do sanity checks, and generate *.mod.c file */
2043static void write_mod_c_file(struct module *mod)
2044{
2045 struct buffer buf = { };
2046 char fname[PATH_MAX];
2047 int ret;
2048
2049 add_header(&buf, mod);
2050 add_exported_symbols(&buf, mod);
2051 add_versions(&buf, mod);
2052 add_depends(&buf, mod);
2053 add_moddevtable(&buf, mod);
2054 add_srcversion(&buf, mod);
2055
2056 ret = snprintf(fname, sizeof(fname), "%s.mod.c", mod->name);
2057 if (ret >= sizeof(fname)) {
2058 error("%s: too long path was truncated\n", fname);
2059 goto free;
2060 }
2061
2062 write_if_changed(&buf, fname);
2063
2064free:
2065 free(buf.p);
2066}
2067
2068/* parse Module.symvers file. line format:
2069 * 0x12345678<tab>symbol<tab>module<tab>export<tab>namespace
2070 **/
2071static void read_dump(const char *fname)
2072{
2073 char *buf, *pos, *line;
2074
2075 buf = read_text_file(fname);
2076 if (!buf)
2077 /* No symbol versions, silently ignore */
2078 return;
2079
2080 pos = buf;
2081
2082 while ((line = get_line(&pos))) {
2083 char *symname, *namespace, *modname, *d, *export;
2084 unsigned int crc;
2085 struct module *mod;
2086 struct symbol *s;
2087 bool gpl_only;
2088
2089 if (!(symname = strchr(line, '\t')))
2090 goto fail;
2091 *symname++ = '\0';
2092 if (!(modname = strchr(symname, '\t')))
2093 goto fail;
2094 *modname++ = '\0';
2095 if (!(export = strchr(modname, '\t')))
2096 goto fail;
2097 *export++ = '\0';
2098 if (!(namespace = strchr(export, '\t')))
2099 goto fail;
2100 *namespace++ = '\0';
2101
2102 crc = strtoul(line, &d, 16);
2103 if (*symname == '\0' || *modname == '\0' || *d != '\0')
2104 goto fail;
2105
2106 if (!strcmp(export, "EXPORT_SYMBOL_GPL")) {
2107 gpl_only = true;
2108 } else if (!strcmp(export, "EXPORT_SYMBOL")) {
2109 gpl_only = false;
2110 } else {
2111 error("%s: unknown license %s. skip", symname, export);
2112 continue;
2113 }
2114
2115 mod = find_module(modname);
2116 if (!mod) {
2117 mod = new_module(modname, strlen(modname));
2118 mod->from_dump = true;
2119 }
2120 s = sym_add_exported(symname, mod, gpl_only, namespace);
2121 sym_set_crc(s, crc);
2122 }
2123 free(buf);
2124 return;
2125fail:
2126 free(buf);
2127 fatal("parse error in symbol dump file\n");
2128}
2129
2130static void write_dump(const char *fname)
2131{
2132 struct buffer buf = { };
2133 struct module *mod;
2134 struct symbol *sym;
2135
2136 list_for_each_entry(mod, &modules, list) {
2137 if (mod->from_dump)
2138 continue;
2139 list_for_each_entry(sym, &mod->exported_symbols, list) {
2140 if (trim_unused_exports && !sym->used)
2141 continue;
2142
2143 buf_printf(&buf, "0x%08x\t%s\t%s\tEXPORT_SYMBOL%s\t%s\n",
2144 sym->crc, sym->name, mod->name,
2145 sym->is_gpl_only ? "_GPL" : "",
2146 sym->namespace);
2147 }
2148 }
2149 write_buf(&buf, fname);
2150 free(buf.p);
2151}
2152
2153static void write_namespace_deps_files(const char *fname)
2154{
2155 struct module *mod;
2156 struct namespace_list *ns;
2157 struct buffer ns_deps_buf = {};
2158
2159 list_for_each_entry(mod, &modules, list) {
2160
2161 if (mod->from_dump || list_empty(&mod->missing_namespaces))
2162 continue;
2163
2164 buf_printf(&ns_deps_buf, "%s.ko:", mod->name);
2165
2166 list_for_each_entry(ns, &mod->missing_namespaces, list)
2167 buf_printf(&ns_deps_buf, " %s", ns->namespace);
2168
2169 buf_printf(&ns_deps_buf, "\n");
2170 }
2171
2172 write_if_changed(&ns_deps_buf, fname);
2173 free(ns_deps_buf.p);
2174}
2175
2176struct dump_list {
2177 struct list_head list;
2178 const char *file;
2179};
2180
2181int main(int argc, char **argv)
2182{
2183 struct module *mod;
2184 char *missing_namespace_deps = NULL;
2185 char *unused_exports_white_list = NULL;
2186 char *dump_write = NULL, *files_source = NULL;
2187 int opt;
2188 LIST_HEAD(dump_lists);
2189 struct dump_list *dl, *dl2;
2190
2191 while ((opt = getopt(argc, argv, "ei:MmnT:to:au:WwENd:")) != -1) {
2192 switch (opt) {
2193 case 'e':
2194 external_module = true;
2195 break;
2196 case 'i':
2197 dl = NOFAIL(malloc(sizeof(*dl)));
2198 dl->file = optarg;
2199 list_add_tail(&dl->list, &dump_lists);
2200 break;
2201 case 'M':
2202 module_enabled = true;
2203 break;
2204 case 'm':
2205 modversions = true;
2206 break;
2207 case 'n':
2208 ignore_missing_files = true;
2209 break;
2210 case 'o':
2211 dump_write = optarg;
2212 break;
2213 case 'a':
2214 all_versions = true;
2215 break;
2216 case 'T':
2217 files_source = optarg;
2218 break;
2219 case 't':
2220 trim_unused_exports = true;
2221 break;
2222 case 'u':
2223 unused_exports_white_list = optarg;
2224 break;
2225 case 'W':
2226 extra_warn = true;
2227 break;
2228 case 'w':
2229 warn_unresolved = true;
2230 break;
2231 case 'E':
2232 sec_mismatch_warn_only = false;
2233 break;
2234 case 'N':
2235 allow_missing_ns_imports = true;
2236 break;
2237 case 'd':
2238 missing_namespace_deps = optarg;
2239 break;
2240 default:
2241 exit(1);
2242 }
2243 }
2244
2245 list_for_each_entry_safe(dl, dl2, &dump_lists, list) {
2246 read_dump(dl->file);
2247 list_del(&dl->list);
2248 free(dl);
2249 }
2250
2251 while (optind < argc)
2252 read_symbols(argv[optind++]);
2253
2254 if (files_source)
2255 read_symbols_from_files(files_source);
2256
2257 list_for_each_entry(mod, &modules, list) {
2258 if (mod->from_dump || mod->is_vmlinux)
2259 continue;
2260
2261 check_modname_len(mod);
2262 check_exports(mod);
2263 }
2264
2265 if (unused_exports_white_list)
2266 handle_white_list_exports(unused_exports_white_list);
2267
2268 list_for_each_entry(mod, &modules, list) {
2269 if (mod->from_dump)
2270 continue;
2271
2272 if (mod->is_vmlinux)
2273 write_vmlinux_export_c_file(mod);
2274 else
2275 write_mod_c_file(mod);
2276 }
2277
2278 if (missing_namespace_deps)
2279 write_namespace_deps_files(missing_namespace_deps);
2280
2281 if (dump_write)
2282 write_dump(dump_write);
2283 if (sec_mismatch_count && !sec_mismatch_warn_only)
2284 error("Section mismatches detected.\n"
2285 "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n");
2286
2287 if (nr_unresolved > MAX_UNRESOLVED_REPORTS)
2288 warn("suppressed %u unresolved symbol warnings because there were too many)\n",
2289 nr_unresolved - MAX_UNRESOLVED_REPORTS);
2290
2291 return error_occurred ? 1 : 0;
2292}