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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 <stdio.h>
16#include <ctype.h>
17#include <string.h>
18#include <limits.h>
19#include <stdbool.h>
20#include <errno.h>
21#include "modpost.h"
22#include "../../include/generated/autoconf.h"
23#include "../../include/linux/license.h"
24#include "../../include/linux/export.h"
25
26/* Are we using CONFIG_MODVERSIONS? */
27int modversions = 0;
28/* Warn about undefined symbols? (do so if we have vmlinux) */
29int have_vmlinux = 0;
30/* Is CONFIG_MODULE_SRCVERSION_ALL set? */
31static int all_versions = 0;
32/* If we are modposting external module set to 1 */
33static int external_module = 0;
34/* Warn about section mismatch in vmlinux if set to 1 */
35static int vmlinux_section_warnings = 1;
36/* Only warn about unresolved symbols */
37static int warn_unresolved = 0;
38/* How a symbol is exported */
39static int sec_mismatch_count = 0;
40static int sec_mismatch_verbose = 1;
41/* ignore missing files */
42static int ignore_missing_files;
43
44enum export {
45 export_plain, export_unused, export_gpl,
46 export_unused_gpl, export_gpl_future, export_unknown
47};
48
49#define PRINTF __attribute__ ((format (printf, 1, 2)))
50
51PRINTF void fatal(const char *fmt, ...)
52{
53 va_list arglist;
54
55 fprintf(stderr, "FATAL: ");
56
57 va_start(arglist, fmt);
58 vfprintf(stderr, fmt, arglist);
59 va_end(arglist);
60
61 exit(1);
62}
63
64PRINTF void warn(const char *fmt, ...)
65{
66 va_list arglist;
67
68 fprintf(stderr, "WARNING: ");
69
70 va_start(arglist, fmt);
71 vfprintf(stderr, fmt, arglist);
72 va_end(arglist);
73}
74
75PRINTF void merror(const char *fmt, ...)
76{
77 va_list arglist;
78
79 fprintf(stderr, "ERROR: ");
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
94static int is_vmlinux(const char *modname)
95{
96 const char *myname;
97
98 myname = strrchr(modname, '/');
99 if (myname)
100 myname++;
101 else
102 myname = modname;
103
104 return (strcmp(myname, "vmlinux") == 0) ||
105 (strcmp(myname, "vmlinux.o") == 0);
106}
107
108void *do_nofail(void *ptr, const char *expr)
109{
110 if (!ptr)
111 fatal("modpost: Memory allocation failure: %s.\n", expr);
112
113 return ptr;
114}
115
116/* A list of all modules we processed */
117static struct module *modules;
118
119static struct module *find_module(char *modname)
120{
121 struct module *mod;
122
123 for (mod = modules; mod; mod = mod->next)
124 if (strcmp(mod->name, modname) == 0)
125 break;
126 return mod;
127}
128
129static struct module *new_module(const char *modname)
130{
131 struct module *mod;
132 char *p;
133
134 mod = NOFAIL(malloc(sizeof(*mod)));
135 memset(mod, 0, sizeof(*mod));
136 p = NOFAIL(strdup(modname));
137
138 /* strip trailing .o */
139 if (strends(p, ".o")) {
140 p[strlen(p) - 2] = '\0';
141 mod->is_dot_o = 1;
142 }
143
144 /* add to list */
145 mod->name = p;
146 mod->gpl_compatible = -1;
147 mod->next = modules;
148 modules = mod;
149
150 return mod;
151}
152
153/* A hash of all exported symbols,
154 * struct symbol is also used for lists of unresolved symbols */
155
156#define SYMBOL_HASH_SIZE 1024
157
158struct symbol {
159 struct symbol *next;
160 struct module *module;
161 unsigned int crc;
162 int crc_valid;
163 unsigned int weak:1;
164 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */
165 unsigned int kernel:1; /* 1 if symbol is from kernel
166 * (only for external modules) **/
167 unsigned int preloaded:1; /* 1 if symbol from Module.symvers, or crc */
168 enum export export; /* Type of export */
169 char name[0];
170};
171
172static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
173
174/* This is based on the hash agorithm from gdbm, via tdb */
175static inline unsigned int tdb_hash(const char *name)
176{
177 unsigned value; /* Used to compute the hash value. */
178 unsigned i; /* Used to cycle through random values. */
179
180 /* Set the initial value from the key size. */
181 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++)
182 value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
183
184 return (1103515243 * value + 12345);
185}
186
187/**
188 * Allocate a new symbols for use in the hash of exported symbols or
189 * the list of unresolved symbols per module
190 **/
191static struct symbol *alloc_symbol(const char *name, unsigned int weak,
192 struct symbol *next)
193{
194 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
195
196 memset(s, 0, sizeof(*s));
197 strcpy(s->name, name);
198 s->weak = weak;
199 s->next = next;
200 return s;
201}
202
203/* For the hash of exported symbols */
204static struct symbol *new_symbol(const char *name, struct module *module,
205 enum export export)
206{
207 unsigned int hash;
208 struct symbol *new;
209
210 hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
211 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
212 new->module = module;
213 new->export = export;
214 return new;
215}
216
217static struct symbol *find_symbol(const char *name)
218{
219 struct symbol *s;
220
221 /* For our purposes, .foo matches foo. PPC64 needs this. */
222 if (name[0] == '.')
223 name++;
224
225 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
226 if (strcmp(s->name, name) == 0)
227 return s;
228 }
229 return NULL;
230}
231
232static struct {
233 const char *str;
234 enum export export;
235} export_list[] = {
236 { .str = "EXPORT_SYMBOL", .export = export_plain },
237 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
238 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
239 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
240 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
241 { .str = "(unknown)", .export = export_unknown },
242};
243
244
245static const char *export_str(enum export ex)
246{
247 return export_list[ex].str;
248}
249
250static enum export export_no(const char *s)
251{
252 int i;
253
254 if (!s)
255 return export_unknown;
256 for (i = 0; export_list[i].export != export_unknown; i++) {
257 if (strcmp(export_list[i].str, s) == 0)
258 return export_list[i].export;
259 }
260 return export_unknown;
261}
262
263static const char *sec_name(struct elf_info *elf, int secindex);
264
265#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
266
267static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
268{
269 const char *secname = sec_name(elf, sec);
270
271 if (strstarts(secname, "___ksymtab+"))
272 return export_plain;
273 else if (strstarts(secname, "___ksymtab_unused+"))
274 return export_unused;
275 else if (strstarts(secname, "___ksymtab_gpl+"))
276 return export_gpl;
277 else if (strstarts(secname, "___ksymtab_unused_gpl+"))
278 return export_unused_gpl;
279 else if (strstarts(secname, "___ksymtab_gpl_future+"))
280 return export_gpl_future;
281 else
282 return export_unknown;
283}
284
285static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
286{
287 if (sec == elf->export_sec)
288 return export_plain;
289 else if (sec == elf->export_unused_sec)
290 return export_unused;
291 else if (sec == elf->export_gpl_sec)
292 return export_gpl;
293 else if (sec == elf->export_unused_gpl_sec)
294 return export_unused_gpl;
295 else if (sec == elf->export_gpl_future_sec)
296 return export_gpl_future;
297 else
298 return export_unknown;
299}
300
301/**
302 * Add an exported symbol - it may have already been added without a
303 * CRC, in this case just update the CRC
304 **/
305static struct symbol *sym_add_exported(const char *name, struct module *mod,
306 enum export export)
307{
308 struct symbol *s = find_symbol(name);
309
310 if (!s) {
311 s = new_symbol(name, mod, export);
312 } else {
313 if (!s->preloaded) {
314 warn("%s: '%s' exported twice. Previous export "
315 "was in %s%s\n", mod->name, name,
316 s->module->name,
317 is_vmlinux(s->module->name) ?"":".ko");
318 } else {
319 /* In case Modules.symvers was out of date */
320 s->module = mod;
321 }
322 }
323 s->preloaded = 0;
324 s->vmlinux = is_vmlinux(mod->name);
325 s->kernel = 0;
326 s->export = export;
327 return s;
328}
329
330static void sym_update_crc(const char *name, struct module *mod,
331 unsigned int crc, enum export export)
332{
333 struct symbol *s = find_symbol(name);
334
335 if (!s) {
336 s = new_symbol(name, mod, export);
337 /* Don't complain when we find it later. */
338 s->preloaded = 1;
339 }
340 s->crc = crc;
341 s->crc_valid = 1;
342}
343
344void *grab_file(const char *filename, unsigned long *size)
345{
346 struct stat st;
347 void *map = MAP_FAILED;
348 int fd;
349
350 fd = open(filename, O_RDONLY);
351 if (fd < 0)
352 return NULL;
353 if (fstat(fd, &st))
354 goto failed;
355
356 *size = st.st_size;
357 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
358
359failed:
360 close(fd);
361 if (map == MAP_FAILED)
362 return NULL;
363 return map;
364}
365
366/**
367 * Return a copy of the next line in a mmap'ed file.
368 * spaces in the beginning of the line is trimmed away.
369 * Return a pointer to a static buffer.
370 **/
371char *get_next_line(unsigned long *pos, void *file, unsigned long size)
372{
373 static char line[4096];
374 int skip = 1;
375 size_t len = 0;
376 signed char *p = (signed char *)file + *pos;
377 char *s = line;
378
379 for (; *pos < size ; (*pos)++) {
380 if (skip && isspace(*p)) {
381 p++;
382 continue;
383 }
384 skip = 0;
385 if (*p != '\n' && (*pos < size)) {
386 len++;
387 *s++ = *p++;
388 if (len > 4095)
389 break; /* Too long, stop */
390 } else {
391 /* End of string */
392 *s = '\0';
393 return line;
394 }
395 }
396 /* End of buffer */
397 return NULL;
398}
399
400void release_file(void *file, unsigned long size)
401{
402 munmap(file, size);
403}
404
405static int parse_elf(struct elf_info *info, const char *filename)
406{
407 unsigned int i;
408 Elf_Ehdr *hdr;
409 Elf_Shdr *sechdrs;
410 Elf_Sym *sym;
411 const char *secstrings;
412 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
413
414 hdr = grab_file(filename, &info->size);
415 if (!hdr) {
416 if (ignore_missing_files) {
417 fprintf(stderr, "%s: %s (ignored)\n", filename,
418 strerror(errno));
419 return 0;
420 }
421 perror(filename);
422 exit(1);
423 }
424 info->hdr = hdr;
425 if (info->size < sizeof(*hdr)) {
426 /* file too small, assume this is an empty .o file */
427 return 0;
428 }
429 /* Is this a valid ELF file? */
430 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
431 (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
432 (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
433 (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
434 /* Not an ELF file - silently ignore it */
435 return 0;
436 }
437 /* Fix endianness in ELF header */
438 hdr->e_type = TO_NATIVE(hdr->e_type);
439 hdr->e_machine = TO_NATIVE(hdr->e_machine);
440 hdr->e_version = TO_NATIVE(hdr->e_version);
441 hdr->e_entry = TO_NATIVE(hdr->e_entry);
442 hdr->e_phoff = TO_NATIVE(hdr->e_phoff);
443 hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
444 hdr->e_flags = TO_NATIVE(hdr->e_flags);
445 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize);
446 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
447 hdr->e_phnum = TO_NATIVE(hdr->e_phnum);
448 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
449 hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
450 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
451 sechdrs = (void *)hdr + hdr->e_shoff;
452 info->sechdrs = sechdrs;
453
454 /* Check if file offset is correct */
455 if (hdr->e_shoff > info->size) {
456 fatal("section header offset=%lu in file '%s' is bigger than "
457 "filesize=%lu\n", (unsigned long)hdr->e_shoff,
458 filename, info->size);
459 return 0;
460 }
461
462 if (hdr->e_shnum == SHN_UNDEF) {
463 /*
464 * There are more than 64k sections,
465 * read count from .sh_size.
466 */
467 info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
468 }
469 else {
470 info->num_sections = hdr->e_shnum;
471 }
472 if (hdr->e_shstrndx == SHN_XINDEX) {
473 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
474 }
475 else {
476 info->secindex_strings = hdr->e_shstrndx;
477 }
478
479 /* Fix endianness in section headers */
480 for (i = 0; i < info->num_sections; i++) {
481 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
482 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
483 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
484 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
485 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
486 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
487 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
488 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
489 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
490 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
491 }
492 /* Find symbol table. */
493 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
494 for (i = 1; i < info->num_sections; i++) {
495 const char *secname;
496 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
497
498 if (!nobits && sechdrs[i].sh_offset > info->size) {
499 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
500 "sizeof(*hrd)=%zu\n", filename,
501 (unsigned long)sechdrs[i].sh_offset,
502 sizeof(*hdr));
503 return 0;
504 }
505 secname = secstrings + sechdrs[i].sh_name;
506 if (strcmp(secname, ".modinfo") == 0) {
507 if (nobits)
508 fatal("%s has NOBITS .modinfo\n", filename);
509 info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
510 info->modinfo_len = sechdrs[i].sh_size;
511 } else if (strcmp(secname, "__ksymtab") == 0)
512 info->export_sec = i;
513 else if (strcmp(secname, "__ksymtab_unused") == 0)
514 info->export_unused_sec = i;
515 else if (strcmp(secname, "__ksymtab_gpl") == 0)
516 info->export_gpl_sec = i;
517 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
518 info->export_unused_gpl_sec = i;
519 else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
520 info->export_gpl_future_sec = i;
521
522 if (sechdrs[i].sh_type == SHT_SYMTAB) {
523 unsigned int sh_link_idx;
524 symtab_idx = i;
525 info->symtab_start = (void *)hdr +
526 sechdrs[i].sh_offset;
527 info->symtab_stop = (void *)hdr +
528 sechdrs[i].sh_offset + sechdrs[i].sh_size;
529 sh_link_idx = sechdrs[i].sh_link;
530 info->strtab = (void *)hdr +
531 sechdrs[sh_link_idx].sh_offset;
532 }
533
534 /* 32bit section no. table? ("more than 64k sections") */
535 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
536 symtab_shndx_idx = i;
537 info->symtab_shndx_start = (void *)hdr +
538 sechdrs[i].sh_offset;
539 info->symtab_shndx_stop = (void *)hdr +
540 sechdrs[i].sh_offset + sechdrs[i].sh_size;
541 }
542 }
543 if (!info->symtab_start)
544 fatal("%s has no symtab?\n", filename);
545
546 /* Fix endianness in symbols */
547 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
548 sym->st_shndx = TO_NATIVE(sym->st_shndx);
549 sym->st_name = TO_NATIVE(sym->st_name);
550 sym->st_value = TO_NATIVE(sym->st_value);
551 sym->st_size = TO_NATIVE(sym->st_size);
552 }
553
554 if (symtab_shndx_idx != ~0U) {
555 Elf32_Word *p;
556 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
557 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
558 filename, sechdrs[symtab_shndx_idx].sh_link,
559 symtab_idx);
560 /* Fix endianness */
561 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
562 p++)
563 *p = TO_NATIVE(*p);
564 }
565
566 return 1;
567}
568
569static void parse_elf_finish(struct elf_info *info)
570{
571 release_file(info->hdr, info->size);
572}
573
574static int ignore_undef_symbol(struct elf_info *info, const char *symname)
575{
576 /* ignore __this_module, it will be resolved shortly */
577 if (strcmp(symname, VMLINUX_SYMBOL_STR(__this_module)) == 0)
578 return 1;
579 /* ignore global offset table */
580 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
581 return 1;
582 if (info->hdr->e_machine == EM_PPC)
583 /* Special register function linked on all modules during final link of .ko */
584 if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 ||
585 strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 ||
586 strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
587 strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0 ||
588 strncmp(symname, "_restvr_", sizeof("_restvr_") - 1) == 0 ||
589 strncmp(symname, "_savevr_", sizeof("_savevr_") - 1) == 0)
590 return 1;
591 if (info->hdr->e_machine == EM_PPC64)
592 /* Special register function linked on all modules during final link of .ko */
593 if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 ||
594 strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0 ||
595 strncmp(symname, "_restvr_", sizeof("_restvr_") - 1) == 0 ||
596 strncmp(symname, "_savevr_", sizeof("_savevr_") - 1) == 0)
597 return 1;
598 /* Do not ignore this symbol */
599 return 0;
600}
601
602#define CRC_PFX VMLINUX_SYMBOL_STR(__crc_)
603#define KSYMTAB_PFX VMLINUX_SYMBOL_STR(__ksymtab_)
604
605static void handle_modversions(struct module *mod, struct elf_info *info,
606 Elf_Sym *sym, const char *symname)
607{
608 unsigned int crc;
609 enum export export;
610
611 if ((!is_vmlinux(mod->name) || mod->is_dot_o) &&
612 strncmp(symname, "__ksymtab", 9) == 0)
613 export = export_from_secname(info, get_secindex(info, sym));
614 else
615 export = export_from_sec(info, get_secindex(info, sym));
616
617 /* CRC'd symbol */
618 if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
619 crc = (unsigned int) sym->st_value;
620 sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
621 export);
622 }
623
624 switch (sym->st_shndx) {
625 case SHN_COMMON:
626 if (!strncmp(symname, "__gnu_lto_", sizeof("__gnu_lto_")-1)) {
627 /* Should warn here, but modpost runs before the linker */
628 } else
629 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
630 break;
631 case SHN_UNDEF:
632 /* undefined symbol */
633 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
634 ELF_ST_BIND(sym->st_info) != STB_WEAK)
635 break;
636 if (ignore_undef_symbol(info, symname))
637 break;
638/* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
639#if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
640/* add compatibility with older glibc */
641#ifndef STT_SPARC_REGISTER
642#define STT_SPARC_REGISTER STT_REGISTER
643#endif
644 if (info->hdr->e_machine == EM_SPARC ||
645 info->hdr->e_machine == EM_SPARCV9) {
646 /* Ignore register directives. */
647 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
648 break;
649 if (symname[0] == '.') {
650 char *munged = strdup(symname);
651 munged[0] = '_';
652 munged[1] = toupper(munged[1]);
653 symname = munged;
654 }
655 }
656#endif
657
658#ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
659 if (symname[0] != '_')
660 break;
661 else
662 symname++;
663#endif
664 mod->unres = alloc_symbol(symname,
665 ELF_ST_BIND(sym->st_info) == STB_WEAK,
666 mod->unres);
667 break;
668 default:
669 /* All exported symbols */
670 if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
671 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
672 export);
673 }
674 if (strcmp(symname, VMLINUX_SYMBOL_STR(init_module)) == 0)
675 mod->has_init = 1;
676 if (strcmp(symname, VMLINUX_SYMBOL_STR(cleanup_module)) == 0)
677 mod->has_cleanup = 1;
678 break;
679 }
680}
681
682/**
683 * Parse tag=value strings from .modinfo section
684 **/
685static char *next_string(char *string, unsigned long *secsize)
686{
687 /* Skip non-zero chars */
688 while (string[0]) {
689 string++;
690 if ((*secsize)-- <= 1)
691 return NULL;
692 }
693
694 /* Skip any zero padding. */
695 while (!string[0]) {
696 string++;
697 if ((*secsize)-- <= 1)
698 return NULL;
699 }
700 return string;
701}
702
703static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
704 const char *tag, char *info)
705{
706 char *p;
707 unsigned int taglen = strlen(tag);
708 unsigned long size = modinfo_len;
709
710 if (info) {
711 size -= info - (char *)modinfo;
712 modinfo = next_string(info, &size);
713 }
714
715 for (p = modinfo; p; p = next_string(p, &size)) {
716 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
717 return p + taglen + 1;
718 }
719 return NULL;
720}
721
722static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
723 const char *tag)
724
725{
726 return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
727}
728
729/**
730 * Test if string s ends in string sub
731 * return 0 if match
732 **/
733static int strrcmp(const char *s, const char *sub)
734{
735 int slen, sublen;
736
737 if (!s || !sub)
738 return 1;
739
740 slen = strlen(s);
741 sublen = strlen(sub);
742
743 if ((slen == 0) || (sublen == 0))
744 return 1;
745
746 if (sublen > slen)
747 return 1;
748
749 return memcmp(s + slen - sublen, sub, sublen);
750}
751
752static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
753{
754 if (sym)
755 return elf->strtab + sym->st_name;
756 else
757 return "(unknown)";
758}
759
760static const char *sec_name(struct elf_info *elf, int secindex)
761{
762 Elf_Shdr *sechdrs = elf->sechdrs;
763 return (void *)elf->hdr +
764 elf->sechdrs[elf->secindex_strings].sh_offset +
765 sechdrs[secindex].sh_name;
766}
767
768static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr)
769{
770 return (void *)elf->hdr +
771 elf->sechdrs[elf->secindex_strings].sh_offset +
772 sechdr->sh_name;
773}
774
775/* if sym is empty or point to a string
776 * like ".[0-9]+" then return 1.
777 * This is the optional prefix added by ld to some sections
778 */
779static int number_prefix(const char *sym)
780{
781 if (*sym++ == '\0')
782 return 1;
783 if (*sym != '.')
784 return 0;
785 do {
786 char c = *sym++;
787 if (c < '0' || c > '9')
788 return 0;
789 } while (*sym);
790 return 1;
791}
792
793/* The pattern is an array of simple patterns.
794 * "foo" will match an exact string equal to "foo"
795 * "*foo" will match a string that ends with "foo"
796 * "foo*" will match a string that begins with "foo"
797 * "foo$" will match a string equal to "foo" or "foo.1"
798 * where the '1' can be any number including several digits.
799 * The $ syntax is for sections where ld append a dot number
800 * to make section name unique.
801 */
802static int match(const char *sym, const char * const pat[])
803{
804 const char *p;
805 while (*pat) {
806 p = *pat++;
807 const char *endp = p + strlen(p) - 1;
808
809 /* "*foo" */
810 if (*p == '*') {
811 if (strrcmp(sym, p + 1) == 0)
812 return 1;
813 }
814 /* "foo*" */
815 else if (*endp == '*') {
816 if (strncmp(sym, p, strlen(p) - 1) == 0)
817 return 1;
818 }
819 /* "foo$" */
820 else if (*endp == '$') {
821 if (strncmp(sym, p, strlen(p) - 1) == 0) {
822 if (number_prefix(sym + strlen(p) - 1))
823 return 1;
824 }
825 }
826 /* no wildcards */
827 else {
828 if (strcmp(p, sym) == 0)
829 return 1;
830 }
831 }
832 /* no match */
833 return 0;
834}
835
836/* sections that we do not want to do full section mismatch check on */
837static const char *section_white_list[] =
838{
839 ".comment*",
840 ".debug*",
841 ".cranges", /* sh64 */
842 ".zdebug*", /* Compressed debug sections. */
843 ".GCC-command-line", /* mn10300 */
844 ".GCC.command.line", /* record-gcc-switches, non mn10300 */
845 ".mdebug*", /* alpha, score, mips etc. */
846 ".pdr", /* alpha, score, mips etc. */
847 ".stab*",
848 ".note*",
849 ".got*",
850 ".toc*",
851 ".xt.prop", /* xtensa */
852 ".xt.lit", /* xtensa */
853 ".arcextmap*", /* arc */
854 ".gnu.linkonce.arcext*", /* arc : modules */
855 ".gnu.lto*",
856 NULL
857};
858
859/*
860 * This is used to find sections missing the SHF_ALLOC flag.
861 * The cause of this is often a section specified in assembler
862 * without "ax" / "aw".
863 */
864static void check_section(const char *modname, struct elf_info *elf,
865 Elf_Shdr *sechdr)
866{
867 const char *sec = sech_name(elf, sechdr);
868
869 if (sechdr->sh_type == SHT_PROGBITS &&
870 !(sechdr->sh_flags & SHF_ALLOC) &&
871 !match(sec, section_white_list)) {
872 warn("%s (%s): unexpected non-allocatable section.\n"
873 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
874 "Note that for example <linux/init.h> contains\n"
875 "section definitions for use in .S files.\n\n",
876 modname, sec);
877 }
878}
879
880
881
882#define ALL_INIT_DATA_SECTIONS \
883 ".init.setup$", ".init.rodata$", ".meminit.rodata$", \
884 ".init.data$", ".meminit.data$"
885#define ALL_EXIT_DATA_SECTIONS \
886 ".exit.data$", ".memexit.data$"
887
888#define ALL_INIT_TEXT_SECTIONS \
889 ".init.text$", ".meminit.text$"
890#define ALL_EXIT_TEXT_SECTIONS \
891 ".exit.text$", ".memexit.text$"
892
893#define ALL_PCI_INIT_SECTIONS \
894 ".pci_fixup_early$", ".pci_fixup_header$", ".pci_fixup_final$", \
895 ".pci_fixup_enable$", ".pci_fixup_resume$", \
896 ".pci_fixup_resume_early$", ".pci_fixup_suspend$"
897
898#define ALL_XXXINIT_SECTIONS MEM_INIT_SECTIONS
899#define ALL_XXXEXIT_SECTIONS MEM_EXIT_SECTIONS
900
901#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
902#define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
903
904#define DATA_SECTIONS ".data$", ".data.rel$"
905#define TEXT_SECTIONS ".text$", ".text.unlikely$"
906
907#define INIT_SECTIONS ".init.*"
908#define MEM_INIT_SECTIONS ".meminit.*"
909
910#define EXIT_SECTIONS ".exit.*"
911#define MEM_EXIT_SECTIONS ".memexit.*"
912
913/* init data sections */
914static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL };
915
916/* all init sections */
917static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL };
918
919/* All init and exit sections (code + data) */
920static const char *init_exit_sections[] =
921 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
922
923/* data section */
924static const char *data_sections[] = { DATA_SECTIONS, NULL };
925
926
927/* symbols in .data that may refer to init/exit sections */
928#define DEFAULT_SYMBOL_WHITE_LIST \
929 "*driver", \
930 "*_template", /* scsi uses *_template a lot */ \
931 "*_timer", /* arm uses ops structures named _timer a lot */ \
932 "*_sht", /* scsi also used *_sht to some extent */ \
933 "*_ops", \
934 "*_probe", \
935 "*_probe_one", \
936 "*_console"
937
938static const char *head_sections[] = { ".head.text*", NULL };
939static const char *linker_symbols[] =
940 { "__init_begin", "_sinittext", "_einittext", NULL };
941
942enum mismatch {
943 TEXT_TO_ANY_INIT,
944 DATA_TO_ANY_INIT,
945 TEXT_TO_ANY_EXIT,
946 DATA_TO_ANY_EXIT,
947 XXXINIT_TO_SOME_INIT,
948 XXXEXIT_TO_SOME_EXIT,
949 ANY_INIT_TO_ANY_EXIT,
950 ANY_EXIT_TO_ANY_INIT,
951 EXPORT_TO_INIT_EXIT,
952};
953
954struct sectioncheck {
955 const char *fromsec[20];
956 const char *tosec[20];
957 enum mismatch mismatch;
958 const char *symbol_white_list[20];
959};
960
961const struct sectioncheck sectioncheck[] = {
962/* Do not reference init/exit code/data from
963 * normal code and data
964 */
965{
966 .fromsec = { TEXT_SECTIONS, NULL },
967 .tosec = { ALL_INIT_SECTIONS, NULL },
968 .mismatch = TEXT_TO_ANY_INIT,
969 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
970},
971{
972 .fromsec = { DATA_SECTIONS, NULL },
973 .tosec = { ALL_XXXINIT_SECTIONS, NULL },
974 .mismatch = DATA_TO_ANY_INIT,
975 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
976},
977{
978 .fromsec = { DATA_SECTIONS, NULL },
979 .tosec = { INIT_SECTIONS, NULL },
980 .mismatch = DATA_TO_ANY_INIT,
981 .symbol_white_list = {
982 "*_template", "*_timer", "*_sht", "*_ops",
983 "*_probe", "*_probe_one", "*_console", NULL
984 },
985},
986{
987 .fromsec = { TEXT_SECTIONS, NULL },
988 .tosec = { ALL_EXIT_SECTIONS, NULL },
989 .mismatch = TEXT_TO_ANY_EXIT,
990 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
991},
992{
993 .fromsec = { DATA_SECTIONS, NULL },
994 .tosec = { ALL_EXIT_SECTIONS, NULL },
995 .mismatch = DATA_TO_ANY_EXIT,
996 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
997},
998/* Do not reference init code/data from meminit code/data */
999{
1000 .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
1001 .tosec = { INIT_SECTIONS, NULL },
1002 .mismatch = XXXINIT_TO_SOME_INIT,
1003 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1004},
1005/* Do not reference exit code/data from memexit code/data */
1006{
1007 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
1008 .tosec = { EXIT_SECTIONS, NULL },
1009 .mismatch = XXXEXIT_TO_SOME_EXIT,
1010 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1011},
1012/* Do not use exit code/data from init code */
1013{
1014 .fromsec = { ALL_INIT_SECTIONS, NULL },
1015 .tosec = { ALL_EXIT_SECTIONS, NULL },
1016 .mismatch = ANY_INIT_TO_ANY_EXIT,
1017 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1018},
1019/* Do not use init code/data from exit code */
1020{
1021 .fromsec = { ALL_EXIT_SECTIONS, NULL },
1022 .tosec = { ALL_INIT_SECTIONS, NULL },
1023 .mismatch = ANY_EXIT_TO_ANY_INIT,
1024 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1025},
1026{
1027 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
1028 .tosec = { INIT_SECTIONS, NULL },
1029 .mismatch = ANY_INIT_TO_ANY_EXIT,
1030 .symbol_white_list = { NULL },
1031},
1032/* Do not export init/exit functions or data */
1033{
1034 .fromsec = { "__ksymtab*", NULL },
1035 .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
1036 .mismatch = EXPORT_TO_INIT_EXIT,
1037 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1038}
1039};
1040
1041static const struct sectioncheck *section_mismatch(
1042 const char *fromsec, const char *tosec)
1043{
1044 int i;
1045 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
1046 const struct sectioncheck *check = §ioncheck[0];
1047
1048 for (i = 0; i < elems; i++) {
1049 if (match(fromsec, check->fromsec) &&
1050 match(tosec, check->tosec))
1051 return check;
1052 check++;
1053 }
1054 return NULL;
1055}
1056
1057/**
1058 * Whitelist to allow certain references to pass with no warning.
1059 *
1060 * Pattern 1:
1061 * If a module parameter is declared __initdata and permissions=0
1062 * then this is legal despite the warning generated.
1063 * We cannot see value of permissions here, so just ignore
1064 * this pattern.
1065 * The pattern is identified by:
1066 * tosec = .init.data
1067 * fromsec = .data*
1068 * atsym =__param*
1069 *
1070 * Pattern 1a:
1071 * module_param_call() ops can refer to __init set function if permissions=0
1072 * The pattern is identified by:
1073 * tosec = .init.text
1074 * fromsec = .data*
1075 * atsym = __param_ops_*
1076 *
1077 * Pattern 2:
1078 * Many drivers utilise a *driver container with references to
1079 * add, remove, probe functions etc.
1080 * the pattern is identified by:
1081 * tosec = init or exit section
1082 * fromsec = data section
1083 * atsym = *driver, *_template, *_sht, *_ops, *_probe,
1084 * *probe_one, *_console, *_timer
1085 *
1086 * Pattern 3:
1087 * Whitelist all references from .head.text to any init section
1088 *
1089 * Pattern 4:
1090 * Some symbols belong to init section but still it is ok to reference
1091 * these from non-init sections as these symbols don't have any memory
1092 * allocated for them and symbol address and value are same. So even
1093 * if init section is freed, its ok to reference those symbols.
1094 * For ex. symbols marking the init section boundaries.
1095 * This pattern is identified by
1096 * refsymname = __init_begin, _sinittext, _einittext
1097 *
1098 **/
1099static int secref_whitelist(const struct sectioncheck *mismatch,
1100 const char *fromsec, const char *fromsym,
1101 const char *tosec, const char *tosym)
1102{
1103 /* Check for pattern 1 */
1104 if (match(tosec, init_data_sections) &&
1105 match(fromsec, data_sections) &&
1106 (strncmp(fromsym, "__param", strlen("__param")) == 0))
1107 return 0;
1108
1109 /* Check for pattern 1a */
1110 if (strcmp(tosec, ".init.text") == 0 &&
1111 match(fromsec, data_sections) &&
1112 (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0))
1113 return 0;
1114
1115 /* Check for pattern 2 */
1116 if (match(tosec, init_exit_sections) &&
1117 match(fromsec, data_sections) &&
1118 match(fromsym, mismatch->symbol_white_list))
1119 return 0;
1120
1121 /* Check for pattern 3 */
1122 if (match(fromsec, head_sections) &&
1123 match(tosec, init_sections))
1124 return 0;
1125
1126 /* Check for pattern 4 */
1127 if (match(tosym, linker_symbols))
1128 return 0;
1129
1130 return 1;
1131}
1132
1133/**
1134 * Find symbol based on relocation record info.
1135 * In some cases the symbol supplied is a valid symbol so
1136 * return refsym. If st_name != 0 we assume this is a valid symbol.
1137 * In other cases the symbol needs to be looked up in the symbol table
1138 * based on section and address.
1139 * **/
1140static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
1141 Elf_Sym *relsym)
1142{
1143 Elf_Sym *sym;
1144 Elf_Sym *near = NULL;
1145 Elf64_Sword distance = 20;
1146 Elf64_Sword d;
1147 unsigned int relsym_secindex;
1148
1149 if (relsym->st_name != 0)
1150 return relsym;
1151
1152 relsym_secindex = get_secindex(elf, relsym);
1153 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1154 if (get_secindex(elf, sym) != relsym_secindex)
1155 continue;
1156 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
1157 continue;
1158 if (sym->st_value == addr)
1159 return sym;
1160 /* Find a symbol nearby - addr are maybe negative */
1161 d = sym->st_value - addr;
1162 if (d < 0)
1163 d = addr - sym->st_value;
1164 if (d < distance) {
1165 distance = d;
1166 near = sym;
1167 }
1168 }
1169 /* We need a close match */
1170 if (distance < 20)
1171 return near;
1172 else
1173 return NULL;
1174}
1175
1176static inline int is_arm_mapping_symbol(const char *str)
1177{
1178 return str[0] == '$' && strchr("atd", str[1])
1179 && (str[2] == '\0' || str[2] == '.');
1180}
1181
1182/*
1183 * If there's no name there, ignore it; likewise, ignore it if it's
1184 * one of the magic symbols emitted used by current ARM tools.
1185 *
1186 * Otherwise if find_symbols_between() returns those symbols, they'll
1187 * fail the whitelist tests and cause lots of false alarms ... fixable
1188 * only by merging __exit and __init sections into __text, bloating
1189 * the kernel (which is especially evil on embedded platforms).
1190 */
1191static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
1192{
1193 const char *name = elf->strtab + sym->st_name;
1194
1195 if (!name || !strlen(name))
1196 return 0;
1197 return !is_arm_mapping_symbol(name);
1198}
1199
1200/*
1201 * Find symbols before or equal addr and after addr - in the section sec.
1202 * If we find two symbols with equal offset prefer one with a valid name.
1203 * The ELF format may have a better way to detect what type of symbol
1204 * it is, but this works for now.
1205 **/
1206static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
1207 const char *sec)
1208{
1209 Elf_Sym *sym;
1210 Elf_Sym *near = NULL;
1211 Elf_Addr distance = ~0;
1212
1213 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1214 const char *symsec;
1215
1216 if (is_shndx_special(sym->st_shndx))
1217 continue;
1218 symsec = sec_name(elf, get_secindex(elf, sym));
1219 if (strcmp(symsec, sec) != 0)
1220 continue;
1221 if (!is_valid_name(elf, sym))
1222 continue;
1223 if (sym->st_value <= addr) {
1224 if ((addr - sym->st_value) < distance) {
1225 distance = addr - sym->st_value;
1226 near = sym;
1227 } else if ((addr - sym->st_value) == distance) {
1228 near = sym;
1229 }
1230 }
1231 }
1232 return near;
1233}
1234
1235/*
1236 * Convert a section name to the function/data attribute
1237 * .init.text => __init
1238 * .memexitconst => __memconst
1239 * etc.
1240 *
1241 * The memory of returned value has been allocated on a heap. The user of this
1242 * method should free it after usage.
1243*/
1244static char *sec2annotation(const char *s)
1245{
1246 if (match(s, init_exit_sections)) {
1247 char *p = malloc(20);
1248 char *r = p;
1249
1250 *p++ = '_';
1251 *p++ = '_';
1252 if (*s == '.')
1253 s++;
1254 while (*s && *s != '.')
1255 *p++ = *s++;
1256 *p = '\0';
1257 if (*s == '.')
1258 s++;
1259 if (strstr(s, "rodata") != NULL)
1260 strcat(p, "const ");
1261 else if (strstr(s, "data") != NULL)
1262 strcat(p, "data ");
1263 else
1264 strcat(p, " ");
1265 return r;
1266 } else {
1267 return strdup("");
1268 }
1269}
1270
1271static int is_function(Elf_Sym *sym)
1272{
1273 if (sym)
1274 return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
1275 else
1276 return -1;
1277}
1278
1279static void print_section_list(const char * const list[20])
1280{
1281 const char *const *s = list;
1282
1283 while (*s) {
1284 fprintf(stderr, "%s", *s);
1285 s++;
1286 if (*s)
1287 fprintf(stderr, ", ");
1288 }
1289 fprintf(stderr, "\n");
1290}
1291
1292/*
1293 * Print a warning about a section mismatch.
1294 * Try to find symbols near it so user can find it.
1295 * Check whitelist before warning - it may be a false positive.
1296 */
1297static void report_sec_mismatch(const char *modname,
1298 const struct sectioncheck *mismatch,
1299 const char *fromsec,
1300 unsigned long long fromaddr,
1301 const char *fromsym,
1302 int from_is_func,
1303 const char *tosec, const char *tosym,
1304 int to_is_func)
1305{
1306 const char *from, *from_p;
1307 const char *to, *to_p;
1308 char *prl_from;
1309 char *prl_to;
1310
1311 switch (from_is_func) {
1312 case 0: from = "variable"; from_p = ""; break;
1313 case 1: from = "function"; from_p = "()"; break;
1314 default: from = "(unknown reference)"; from_p = ""; break;
1315 }
1316 switch (to_is_func) {
1317 case 0: to = "variable"; to_p = ""; break;
1318 case 1: to = "function"; to_p = "()"; break;
1319 default: to = "(unknown reference)"; to_p = ""; break;
1320 }
1321
1322 sec_mismatch_count++;
1323 if (!sec_mismatch_verbose)
1324 return;
1325
1326 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1327 "to the %s %s:%s%s\n",
1328 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
1329 tosym, to_p);
1330
1331 switch (mismatch->mismatch) {
1332 case TEXT_TO_ANY_INIT:
1333 prl_from = sec2annotation(fromsec);
1334 prl_to = sec2annotation(tosec);
1335 fprintf(stderr,
1336 "The function %s%s() references\n"
1337 "the %s %s%s%s.\n"
1338 "This is often because %s lacks a %s\n"
1339 "annotation or the annotation of %s is wrong.\n",
1340 prl_from, fromsym,
1341 to, prl_to, tosym, to_p,
1342 fromsym, prl_to, tosym);
1343 free(prl_from);
1344 free(prl_to);
1345 break;
1346 case DATA_TO_ANY_INIT: {
1347 prl_to = sec2annotation(tosec);
1348 fprintf(stderr,
1349 "The variable %s references\n"
1350 "the %s %s%s%s\n"
1351 "If the reference is valid then annotate the\n"
1352 "variable with __init* or __refdata (see linux/init.h) "
1353 "or name the variable:\n",
1354 fromsym, to, prl_to, tosym, to_p);
1355 print_section_list(mismatch->symbol_white_list);
1356 free(prl_to);
1357 break;
1358 }
1359 case TEXT_TO_ANY_EXIT:
1360 prl_to = sec2annotation(tosec);
1361 fprintf(stderr,
1362 "The function %s() references a %s in an exit section.\n"
1363 "Often the %s %s%s has valid usage outside the exit section\n"
1364 "and the fix is to remove the %sannotation of %s.\n",
1365 fromsym, to, to, tosym, to_p, prl_to, tosym);
1366 free(prl_to);
1367 break;
1368 case DATA_TO_ANY_EXIT: {
1369 prl_to = sec2annotation(tosec);
1370 fprintf(stderr,
1371 "The variable %s references\n"
1372 "the %s %s%s%s\n"
1373 "If the reference is valid then annotate the\n"
1374 "variable with __exit* (see linux/init.h) or "
1375 "name the variable:\n",
1376 fromsym, to, prl_to, tosym, to_p);
1377 print_section_list(mismatch->symbol_white_list);
1378 free(prl_to);
1379 break;
1380 }
1381 case XXXINIT_TO_SOME_INIT:
1382 case XXXEXIT_TO_SOME_EXIT:
1383 prl_from = sec2annotation(fromsec);
1384 prl_to = sec2annotation(tosec);
1385 fprintf(stderr,
1386 "The %s %s%s%s references\n"
1387 "a %s %s%s%s.\n"
1388 "If %s is only used by %s then\n"
1389 "annotate %s with a matching annotation.\n",
1390 from, prl_from, fromsym, from_p,
1391 to, prl_to, tosym, to_p,
1392 tosym, fromsym, tosym);
1393 free(prl_from);
1394 free(prl_to);
1395 break;
1396 case ANY_INIT_TO_ANY_EXIT:
1397 prl_from = sec2annotation(fromsec);
1398 prl_to = sec2annotation(tosec);
1399 fprintf(stderr,
1400 "The %s %s%s%s references\n"
1401 "a %s %s%s%s.\n"
1402 "This is often seen when error handling "
1403 "in the init function\n"
1404 "uses functionality in the exit path.\n"
1405 "The fix is often to remove the %sannotation of\n"
1406 "%s%s so it may be used outside an exit section.\n",
1407 from, prl_from, fromsym, from_p,
1408 to, prl_to, tosym, to_p,
1409 prl_to, tosym, to_p);
1410 free(prl_from);
1411 free(prl_to);
1412 break;
1413 case ANY_EXIT_TO_ANY_INIT:
1414 prl_from = sec2annotation(fromsec);
1415 prl_to = sec2annotation(tosec);
1416 fprintf(stderr,
1417 "The %s %s%s%s references\n"
1418 "a %s %s%s%s.\n"
1419 "This is often seen when error handling "
1420 "in the exit function\n"
1421 "uses functionality in the init path.\n"
1422 "The fix is often to remove the %sannotation of\n"
1423 "%s%s so it may be used outside an init section.\n",
1424 from, prl_from, fromsym, from_p,
1425 to, prl_to, tosym, to_p,
1426 prl_to, tosym, to_p);
1427 free(prl_from);
1428 free(prl_to);
1429 break;
1430 case EXPORT_TO_INIT_EXIT:
1431 prl_to = sec2annotation(tosec);
1432 fprintf(stderr,
1433 "The symbol %s is exported and annotated %s\n"
1434 "Fix this by removing the %sannotation of %s "
1435 "or drop the export.\n",
1436 tosym, prl_to, prl_to, tosym);
1437 free(prl_to);
1438 break;
1439 }
1440 fprintf(stderr, "\n");
1441}
1442
1443static void check_section_mismatch(const char *modname, struct elf_info *elf,
1444 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1445{
1446 const char *tosec;
1447 const struct sectioncheck *mismatch;
1448
1449 tosec = sec_name(elf, get_secindex(elf, sym));
1450 mismatch = section_mismatch(fromsec, tosec);
1451 if (mismatch) {
1452 Elf_Sym *to;
1453 Elf_Sym *from;
1454 const char *tosym;
1455 const char *fromsym;
1456
1457 from = find_elf_symbol2(elf, r->r_offset, fromsec);
1458 fromsym = sym_name(elf, from);
1459 to = find_elf_symbol(elf, r->r_addend, sym);
1460 tosym = sym_name(elf, to);
1461
1462 if (!strncmp(fromsym, "reference___initcall",
1463 sizeof("reference___initcall")-1))
1464 return;
1465
1466 /* check whitelist - we may ignore it */
1467 if (secref_whitelist(mismatch,
1468 fromsec, fromsym, tosec, tosym)) {
1469 report_sec_mismatch(modname, mismatch,
1470 fromsec, r->r_offset, fromsym,
1471 is_function(from), tosec, tosym,
1472 is_function(to));
1473 }
1474 }
1475}
1476
1477static unsigned int *reloc_location(struct elf_info *elf,
1478 Elf_Shdr *sechdr, Elf_Rela *r)
1479{
1480 Elf_Shdr *sechdrs = elf->sechdrs;
1481 int section = sechdr->sh_info;
1482
1483 return (void *)elf->hdr + sechdrs[section].sh_offset +
1484 r->r_offset;
1485}
1486
1487static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1488{
1489 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1490 unsigned int *location = reloc_location(elf, sechdr, r);
1491
1492 switch (r_typ) {
1493 case R_386_32:
1494 r->r_addend = TO_NATIVE(*location);
1495 break;
1496 case R_386_PC32:
1497 r->r_addend = TO_NATIVE(*location) + 4;
1498 /* For CONFIG_RELOCATABLE=y */
1499 if (elf->hdr->e_type == ET_EXEC)
1500 r->r_addend += r->r_offset;
1501 break;
1502 }
1503 return 0;
1504}
1505
1506#ifndef R_ARM_CALL
1507#define R_ARM_CALL 28
1508#endif
1509#ifndef R_ARM_JUMP24
1510#define R_ARM_JUMP24 29
1511#endif
1512
1513#ifndef R_ARM_THM_CALL
1514#define R_ARM_THM_CALL 10
1515#endif
1516#ifndef R_ARM_THM_JUMP24
1517#define R_ARM_THM_JUMP24 30
1518#endif
1519#ifndef R_ARM_THM_JUMP19
1520#define R_ARM_THM_JUMP19 51
1521#endif
1522
1523static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1524{
1525 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1526
1527 switch (r_typ) {
1528 case R_ARM_ABS32:
1529 /* From ARM ABI: (S + A) | T */
1530 r->r_addend = (int)(long)
1531 (elf->symtab_start + ELF_R_SYM(r->r_info));
1532 break;
1533 case R_ARM_PC24:
1534 case R_ARM_CALL:
1535 case R_ARM_JUMP24:
1536 case R_ARM_THM_CALL:
1537 case R_ARM_THM_JUMP24:
1538 case R_ARM_THM_JUMP19:
1539 /* From ARM ABI: ((S + A) | T) - P */
1540 r->r_addend = (int)(long)(elf->hdr +
1541 sechdr->sh_offset +
1542 (r->r_offset - sechdr->sh_addr));
1543 break;
1544 default:
1545 return 1;
1546 }
1547 return 0;
1548}
1549
1550static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1551{
1552 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1553 unsigned int *location = reloc_location(elf, sechdr, r);
1554 unsigned int inst;
1555
1556 if (r_typ == R_MIPS_HI16)
1557 return 1; /* skip this */
1558 inst = TO_NATIVE(*location);
1559 switch (r_typ) {
1560 case R_MIPS_LO16:
1561 r->r_addend = inst & 0xffff;
1562 break;
1563 case R_MIPS_26:
1564 r->r_addend = (inst & 0x03ffffff) << 2;
1565 break;
1566 case R_MIPS_32:
1567 r->r_addend = inst;
1568 break;
1569 }
1570 return 0;
1571}
1572
1573static void section_rela(const char *modname, struct elf_info *elf,
1574 Elf_Shdr *sechdr)
1575{
1576 Elf_Sym *sym;
1577 Elf_Rela *rela;
1578 Elf_Rela r;
1579 unsigned int r_sym;
1580 const char *fromsec;
1581
1582 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
1583 Elf_Rela *stop = (void *)start + sechdr->sh_size;
1584
1585 fromsec = sech_name(elf, sechdr);
1586 fromsec += strlen(".rela");
1587 /* if from section (name) is know good then skip it */
1588 if (match(fromsec, section_white_list))
1589 return;
1590
1591 for (rela = start; rela < stop; rela++) {
1592 r.r_offset = TO_NATIVE(rela->r_offset);
1593#if KERNEL_ELFCLASS == ELFCLASS64
1594 if (elf->hdr->e_machine == EM_MIPS) {
1595 unsigned int r_typ;
1596 r_sym = ELF64_MIPS_R_SYM(rela->r_info);
1597 r_sym = TO_NATIVE(r_sym);
1598 r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
1599 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1600 } else {
1601 r.r_info = TO_NATIVE(rela->r_info);
1602 r_sym = ELF_R_SYM(r.r_info);
1603 }
1604#else
1605 r.r_info = TO_NATIVE(rela->r_info);
1606 r_sym = ELF_R_SYM(r.r_info);
1607#endif
1608 r.r_addend = TO_NATIVE(rela->r_addend);
1609 sym = elf->symtab_start + r_sym;
1610 /* Skip special sections */
1611 if (is_shndx_special(sym->st_shndx))
1612 continue;
1613 check_section_mismatch(modname, elf, &r, sym, fromsec);
1614 }
1615}
1616
1617static void section_rel(const char *modname, struct elf_info *elf,
1618 Elf_Shdr *sechdr)
1619{
1620 Elf_Sym *sym;
1621 Elf_Rel *rel;
1622 Elf_Rela r;
1623 unsigned int r_sym;
1624 const char *fromsec;
1625
1626 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
1627 Elf_Rel *stop = (void *)start + sechdr->sh_size;
1628
1629 fromsec = sech_name(elf, sechdr);
1630 fromsec += strlen(".rel");
1631 /* if from section (name) is know good then skip it */
1632 if (match(fromsec, section_white_list))
1633 return;
1634
1635 for (rel = start; rel < stop; rel++) {
1636 r.r_offset = TO_NATIVE(rel->r_offset);
1637#if KERNEL_ELFCLASS == ELFCLASS64
1638 if (elf->hdr->e_machine == EM_MIPS) {
1639 unsigned int r_typ;
1640 r_sym = ELF64_MIPS_R_SYM(rel->r_info);
1641 r_sym = TO_NATIVE(r_sym);
1642 r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
1643 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1644 } else {
1645 r.r_info = TO_NATIVE(rel->r_info);
1646 r_sym = ELF_R_SYM(r.r_info);
1647 }
1648#else
1649 r.r_info = TO_NATIVE(rel->r_info);
1650 r_sym = ELF_R_SYM(r.r_info);
1651#endif
1652 r.r_addend = 0;
1653 switch (elf->hdr->e_machine) {
1654 case EM_386:
1655 if (addend_386_rel(elf, sechdr, &r))
1656 continue;
1657 break;
1658 case EM_ARM:
1659 if (addend_arm_rel(elf, sechdr, &r))
1660 continue;
1661 break;
1662 case EM_MIPS:
1663 if (addend_mips_rel(elf, sechdr, &r))
1664 continue;
1665 break;
1666 }
1667 sym = elf->symtab_start + r_sym;
1668 /* Skip special sections */
1669 if (is_shndx_special(sym->st_shndx))
1670 continue;
1671 check_section_mismatch(modname, elf, &r, sym, fromsec);
1672 }
1673}
1674
1675/**
1676 * A module includes a number of sections that are discarded
1677 * either when loaded or when used as built-in.
1678 * For loaded modules all functions marked __init and all data
1679 * marked __initdata will be discarded when the module has been initialized.
1680 * Likewise for modules used built-in the sections marked __exit
1681 * are discarded because __exit marked function are supposed to be called
1682 * only when a module is unloaded which never happens for built-in modules.
1683 * The check_sec_ref() function traverses all relocation records
1684 * to find all references to a section that reference a section that will
1685 * be discarded and warns about it.
1686 **/
1687static void check_sec_ref(struct module *mod, const char *modname,
1688 struct elf_info *elf)
1689{
1690 int i;
1691 Elf_Shdr *sechdrs = elf->sechdrs;
1692
1693 /* Walk through all sections */
1694 for (i = 0; i < elf->num_sections; i++) {
1695 check_section(modname, elf, &elf->sechdrs[i]);
1696 /* We want to process only relocation sections and not .init */
1697 if (sechdrs[i].sh_type == SHT_RELA)
1698 section_rela(modname, elf, &elf->sechdrs[i]);
1699 else if (sechdrs[i].sh_type == SHT_REL)
1700 section_rel(modname, elf, &elf->sechdrs[i]);
1701 }
1702}
1703
1704static char *remove_dot(char *s)
1705{
1706 char *end;
1707 int n = strcspn(s, ".");
1708
1709 if (n > 0 && s[n] != 0) {
1710 strtoul(s + n + 1, &end, 10);
1711 if (end > s + n + 1 && (*end == '.' || *end == 0))
1712 s[n] = 0;
1713 }
1714 return s;
1715}
1716
1717static void read_symbols(char *modname)
1718{
1719 const char *symname;
1720 char *version;
1721 char *license;
1722 struct module *mod;
1723 struct elf_info info = { };
1724 Elf_Sym *sym;
1725
1726 if (!parse_elf(&info, modname))
1727 return;
1728
1729 mod = new_module(modname);
1730
1731 /* When there's no vmlinux, don't print warnings about
1732 * unresolved symbols (since there'll be too many ;) */
1733 if (is_vmlinux(modname)) {
1734 have_vmlinux = 1;
1735 mod->skip = 1;
1736 }
1737
1738 license = get_modinfo(info.modinfo, info.modinfo_len, "license");
1739 if (info.modinfo && !license && !is_vmlinux(modname))
1740 warn("modpost: missing MODULE_LICENSE() in %s\n"
1741 "see include/linux/module.h for "
1742 "more information\n", modname);
1743 while (license) {
1744 if (license_is_gpl_compatible(license))
1745 mod->gpl_compatible = 1;
1746 else {
1747 mod->gpl_compatible = 0;
1748 break;
1749 }
1750 license = get_next_modinfo(info.modinfo, info.modinfo_len,
1751 "license", license);
1752 }
1753
1754 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
1755 symname = remove_dot(info.strtab + sym->st_name);
1756
1757 handle_modversions(mod, &info, sym, symname);
1758 handle_moddevtable(mod, &info, sym, symname);
1759 }
1760 if (!is_vmlinux(modname) ||
1761 (is_vmlinux(modname) && vmlinux_section_warnings))
1762 check_sec_ref(mod, modname, &info);
1763
1764 version = get_modinfo(info.modinfo, info.modinfo_len, "version");
1765 if (version)
1766 maybe_frob_rcs_version(modname, version, info.modinfo,
1767 version - (char *)info.hdr);
1768 if (version || (all_versions && !is_vmlinux(modname)))
1769 get_src_version(modname, mod->srcversion,
1770 sizeof(mod->srcversion)-1);
1771
1772 parse_elf_finish(&info);
1773
1774 /* Our trick to get versioning for module struct etc. - it's
1775 * never passed as an argument to an exported function, so
1776 * the automatic versioning doesn't pick it up, but it's really
1777 * important anyhow */
1778 if (modversions)
1779 mod->unres = alloc_symbol("module_layout", 0, mod->unres);
1780}
1781
1782static void read_symbols_from_files(const char *filename)
1783{
1784 FILE *in = stdin;
1785 char fname[PATH_MAX];
1786
1787 if (strcmp(filename, "-") != 0) {
1788 in = fopen(filename, "r");
1789 if (!in)
1790 fatal("Can't open filenames file %s: %m", filename);
1791 }
1792
1793 while (fgets(fname, PATH_MAX, in) != NULL) {
1794 if (strends(fname, "\n"))
1795 fname[strlen(fname)-1] = '\0';
1796 read_symbols(fname);
1797 }
1798
1799 if (in != stdin)
1800 fclose(in);
1801}
1802
1803#define SZ 500
1804
1805/* We first write the generated file into memory using the
1806 * following helper, then compare to the file on disk and
1807 * only update the later if anything changed */
1808
1809void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
1810 const char *fmt, ...)
1811{
1812 char tmp[SZ];
1813 int len;
1814 va_list ap;
1815
1816 va_start(ap, fmt);
1817 len = vsnprintf(tmp, SZ, fmt, ap);
1818 buf_write(buf, tmp, len);
1819 va_end(ap);
1820}
1821
1822void buf_write(struct buffer *buf, const char *s, int len)
1823{
1824 if (buf->size - buf->pos < len) {
1825 buf->size += len + SZ;
1826 buf->p = realloc(buf->p, buf->size);
1827 }
1828 strncpy(buf->p + buf->pos, s, len);
1829 buf->pos += len;
1830}
1831
1832static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
1833{
1834 const char *e = is_vmlinux(m) ?"":".ko";
1835
1836 switch (exp) {
1837 case export_gpl:
1838 fatal("modpost: GPL-incompatible module %s%s "
1839 "uses GPL-only symbol '%s'\n", m, e, s);
1840 break;
1841 case export_unused_gpl:
1842 fatal("modpost: GPL-incompatible module %s%s "
1843 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
1844 break;
1845 case export_gpl_future:
1846 warn("modpost: GPL-incompatible module %s%s "
1847 "uses future GPL-only symbol '%s'\n", m, e, s);
1848 break;
1849 case export_plain:
1850 case export_unused:
1851 case export_unknown:
1852 /* ignore */
1853 break;
1854 }
1855}
1856
1857static void check_for_unused(enum export exp, const char *m, const char *s)
1858{
1859 const char *e = is_vmlinux(m) ?"":".ko";
1860
1861 switch (exp) {
1862 case export_unused:
1863 case export_unused_gpl:
1864 warn("modpost: module %s%s "
1865 "uses symbol '%s' marked UNUSED\n", m, e, s);
1866 break;
1867 default:
1868 /* ignore */
1869 break;
1870 }
1871}
1872
1873static void check_exports(struct module *mod)
1874{
1875 struct symbol *s, *exp;
1876
1877 for (s = mod->unres; s; s = s->next) {
1878 const char *basename;
1879 exp = find_symbol(s->name);
1880 if (!exp || exp->module == mod)
1881 continue;
1882 basename = strrchr(mod->name, '/');
1883 if (basename)
1884 basename++;
1885 else
1886 basename = mod->name;
1887 if (!mod->gpl_compatible)
1888 check_for_gpl_usage(exp->export, basename, exp->name);
1889 check_for_unused(exp->export, basename, exp->name);
1890 }
1891}
1892
1893/**
1894 * Header for the generated file
1895 **/
1896static void add_header(struct buffer *b, struct module *mod)
1897{
1898 buf_printf(b, "#include <linux/module.h>\n");
1899 buf_printf(b, "#include <linux/vermagic.h>\n");
1900 buf_printf(b, "#include <linux/compiler.h>\n");
1901 buf_printf(b, "\n");
1902 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1903 buf_printf(b, "\n");
1904 buf_printf(b, "__visible struct module __this_module\n");
1905 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
1906 buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
1907 if (mod->has_init)
1908 buf_printf(b, "\t.init = init_module,\n");
1909 if (mod->has_cleanup)
1910 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
1911 "\t.exit = cleanup_module,\n"
1912 "#endif\n");
1913 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
1914 buf_printf(b, "};\n");
1915}
1916
1917static void add_intree_flag(struct buffer *b, int is_intree)
1918{
1919 if (is_intree)
1920 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
1921}
1922
1923static void add_staging_flag(struct buffer *b, const char *name)
1924{
1925 static const char *staging_dir = "drivers/staging";
1926
1927 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0)
1928 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
1929}
1930
1931/**
1932 * Record CRCs for unresolved symbols
1933 **/
1934static int add_versions(struct buffer *b, struct module *mod)
1935{
1936 struct symbol *s, *exp;
1937 int err = 0;
1938
1939 for (s = mod->unres; s; s = s->next) {
1940 exp = find_symbol(s->name);
1941 if (!exp || exp->module == mod) {
1942 if (have_vmlinux && !s->weak) {
1943 if (warn_unresolved) {
1944 warn("\"%s\" [%s.ko] undefined!\n",
1945 s->name, mod->name);
1946 } else {
1947 merror("\"%s\" [%s.ko] undefined!\n",
1948 s->name, mod->name);
1949 err = 1;
1950 }
1951 }
1952 continue;
1953 }
1954 s->module = exp->module;
1955 s->crc_valid = exp->crc_valid;
1956 s->crc = exp->crc;
1957 }
1958
1959 if (!modversions)
1960 return err;
1961
1962 buf_printf(b, "\n");
1963 buf_printf(b, "static const struct modversion_info ____versions[]\n");
1964 buf_printf(b, "__used\n");
1965 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n");
1966
1967 for (s = mod->unres; s; s = s->next) {
1968 if (!s->module)
1969 continue;
1970 if (!s->crc_valid) {
1971 warn("\"%s\" [%s.ko] has no CRC!\n",
1972 s->name, mod->name);
1973 continue;
1974 }
1975 buf_printf(b, "\t{ %#8x, __VMLINUX_SYMBOL_STR(%s) },\n",
1976 s->crc, s->name);
1977 }
1978
1979 buf_printf(b, "};\n");
1980
1981 return err;
1982}
1983
1984static void add_depends(struct buffer *b, struct module *mod,
1985 struct module *modules)
1986{
1987 struct symbol *s;
1988 struct module *m;
1989 int first = 1;
1990
1991 for (m = modules; m; m = m->next)
1992 m->seen = is_vmlinux(m->name);
1993
1994 buf_printf(b, "\n");
1995 buf_printf(b, "static const char __module_depends[]\n");
1996 buf_printf(b, "__used\n");
1997 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n");
1998 buf_printf(b, "\"depends=");
1999 for (s = mod->unres; s; s = s->next) {
2000 const char *p;
2001 if (!s->module)
2002 continue;
2003
2004 if (s->module->seen)
2005 continue;
2006
2007 s->module->seen = 1;
2008 p = strrchr(s->module->name, '/');
2009 if (p)
2010 p++;
2011 else
2012 p = s->module->name;
2013 buf_printf(b, "%s%s", first ? "" : ",", p);
2014 first = 0;
2015 }
2016 buf_printf(b, "\";\n");
2017}
2018
2019static void add_srcversion(struct buffer *b, struct module *mod)
2020{
2021 if (mod->srcversion[0]) {
2022 buf_printf(b, "\n");
2023 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
2024 mod->srcversion);
2025 }
2026}
2027
2028static void write_if_changed(struct buffer *b, const char *fname)
2029{
2030 char *tmp;
2031 FILE *file;
2032 struct stat st;
2033
2034 file = fopen(fname, "r");
2035 if (!file)
2036 goto write;
2037
2038 if (fstat(fileno(file), &st) < 0)
2039 goto close_write;
2040
2041 if (st.st_size != b->pos)
2042 goto close_write;
2043
2044 tmp = NOFAIL(malloc(b->pos));
2045 if (fread(tmp, 1, b->pos, file) != b->pos)
2046 goto free_write;
2047
2048 if (memcmp(tmp, b->p, b->pos) != 0)
2049 goto free_write;
2050
2051 free(tmp);
2052 fclose(file);
2053 return;
2054
2055 free_write:
2056 free(tmp);
2057 close_write:
2058 fclose(file);
2059 write:
2060 file = fopen(fname, "w");
2061 if (!file) {
2062 perror(fname);
2063 exit(1);
2064 }
2065 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
2066 perror(fname);
2067 exit(1);
2068 }
2069 fclose(file);
2070}
2071
2072/* parse Module.symvers file. line format:
2073 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
2074 **/
2075static void read_dump(const char *fname, unsigned int kernel)
2076{
2077 unsigned long size, pos = 0;
2078 void *file = grab_file(fname, &size);
2079 char *line;
2080
2081 if (!file)
2082 /* No symbol versions, silently ignore */
2083 return;
2084
2085 while ((line = get_next_line(&pos, file, size))) {
2086 char *symname, *modname, *d, *export, *end;
2087 unsigned int crc;
2088 struct module *mod;
2089 struct symbol *s;
2090
2091 if (!(symname = strchr(line, '\t')))
2092 goto fail;
2093 *symname++ = '\0';
2094 if (!(modname = strchr(symname, '\t')))
2095 goto fail;
2096 *modname++ = '\0';
2097 if ((export = strchr(modname, '\t')) != NULL)
2098 *export++ = '\0';
2099 if (export && ((end = strchr(export, '\t')) != NULL))
2100 *end = '\0';
2101 crc = strtoul(line, &d, 16);
2102 if (*symname == '\0' || *modname == '\0' || *d != '\0')
2103 goto fail;
2104 mod = find_module(modname);
2105 if (!mod) {
2106 if (is_vmlinux(modname))
2107 have_vmlinux = 1;
2108 mod = new_module(modname);
2109 mod->skip = 1;
2110 }
2111 s = sym_add_exported(symname, mod, export_no(export));
2112 s->kernel = kernel;
2113 s->preloaded = 1;
2114 sym_update_crc(symname, mod, crc, export_no(export));
2115 }
2116 return;
2117fail:
2118 fatal("parse error in symbol dump file\n");
2119}
2120
2121/* For normal builds always dump all symbols.
2122 * For external modules only dump symbols
2123 * that are not read from kernel Module.symvers.
2124 **/
2125static int dump_sym(struct symbol *sym)
2126{
2127 if (!external_module)
2128 return 1;
2129 if (sym->vmlinux || sym->kernel)
2130 return 0;
2131 return 1;
2132}
2133
2134static void write_dump(const char *fname)
2135{
2136 struct buffer buf = { };
2137 struct symbol *symbol;
2138 int n;
2139
2140 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
2141 symbol = symbolhash[n];
2142 while (symbol) {
2143 if (dump_sym(symbol))
2144 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
2145 symbol->crc, symbol->name,
2146 symbol->module->name,
2147 export_str(symbol->export));
2148 symbol = symbol->next;
2149 }
2150 }
2151 write_if_changed(&buf, fname);
2152}
2153
2154struct ext_sym_list {
2155 struct ext_sym_list *next;
2156 const char *file;
2157};
2158
2159int main(int argc, char **argv)
2160{
2161 struct module *mod;
2162 struct buffer buf = { };
2163 char *kernel_read = NULL, *module_read = NULL;
2164 char *dump_write = NULL, *files_source = NULL;
2165 int opt;
2166 int err;
2167 struct ext_sym_list *extsym_iter;
2168 struct ext_sym_list *extsym_start = NULL;
2169
2170 while ((opt = getopt(argc, argv, "i:I:e:mnsST:o:awM:K:")) != -1) {
2171 switch (opt) {
2172 case 'i':
2173 kernel_read = optarg;
2174 break;
2175 case 'I':
2176 module_read = optarg;
2177 external_module = 1;
2178 break;
2179 case 'e':
2180 external_module = 1;
2181 extsym_iter =
2182 NOFAIL(malloc(sizeof(*extsym_iter)));
2183 extsym_iter->next = extsym_start;
2184 extsym_iter->file = optarg;
2185 extsym_start = extsym_iter;
2186 break;
2187 case 'm':
2188 modversions = 1;
2189 break;
2190 case 'n':
2191 ignore_missing_files = 1;
2192 break;
2193 case 'o':
2194 dump_write = optarg;
2195 break;
2196 case 'a':
2197 all_versions = 1;
2198 break;
2199 case 's':
2200 vmlinux_section_warnings = 0;
2201 break;
2202 case 'S':
2203 sec_mismatch_verbose = 0;
2204 break;
2205 case 'T':
2206 files_source = optarg;
2207 break;
2208 case 'w':
2209 warn_unresolved = 1;
2210 break;
2211 default:
2212 exit(1);
2213 }
2214 }
2215
2216 if (kernel_read)
2217 read_dump(kernel_read, 1);
2218 if (module_read)
2219 read_dump(module_read, 0);
2220 while (extsym_start) {
2221 read_dump(extsym_start->file, 0);
2222 extsym_iter = extsym_start->next;
2223 free(extsym_start);
2224 extsym_start = extsym_iter;
2225 }
2226
2227 while (optind < argc)
2228 read_symbols(argv[optind++]);
2229
2230 if (files_source)
2231 read_symbols_from_files(files_source);
2232
2233 for (mod = modules; mod; mod = mod->next) {
2234 if (mod->skip)
2235 continue;
2236 check_exports(mod);
2237 }
2238
2239 err = 0;
2240
2241 for (mod = modules; mod; mod = mod->next) {
2242 char fname[strlen(mod->name) + 10];
2243
2244 if (mod->skip)
2245 continue;
2246
2247 buf.pos = 0;
2248
2249 add_header(&buf, mod);
2250 add_intree_flag(&buf, !external_module);
2251 add_staging_flag(&buf, mod->name);
2252 err |= add_versions(&buf, mod);
2253 add_depends(&buf, mod, modules);
2254 add_moddevtable(&buf, mod);
2255 add_srcversion(&buf, mod);
2256
2257 sprintf(fname, "%s.mod.c", mod->name);
2258 write_if_changed(&buf, fname);
2259 }
2260
2261 if (dump_write)
2262 write_dump(dump_write);
2263 if (sec_mismatch_count && !sec_mismatch_verbose)
2264 warn("modpost: Found %d section mismatch(es).\n"
2265 "To see full details build your kernel with:\n"
2266 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
2267 sec_mismatch_count);
2268
2269 return err;
2270}