projects/linux·blob v3.4-rc1 · refs

2207 lines · 56.2 KiB

1/* Postprocess module symbol versions
2 *
3 * Copyright 2003 Kai Germaschewski
4 * Copyright 2002-2004 Rusty Russell, IBM Corporation
5 * Copyright 2006-2008 Sam Ravnborg
6 * Based in part on module-init-tools/depmod.c,file2alias
7 *
8 * This software may be used and distributed according to the terms
9 * of the GNU General Public License, incorporated herein by reference.
10 *
11 * Usage: modpost vmlinux module1.o module2.o ...
12 */
13
14#define _GNU_SOURCE
15#include <stdio.h>
16#include <ctype.h>
17#include <string.h>
18#include "modpost.h"
19#include "../../include/generated/autoconf.h"
20#include "../../include/linux/license.h"
21
22/* Some toolchains use a `_' prefix for all user symbols. */
23#ifdef CONFIG_SYMBOL_PREFIX
24#define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX
25#else
26#define MODULE_SYMBOL_PREFIX ""
27#endif
28
29
30/* Are we using CONFIG_MODVERSIONS? */
31int modversions = 0;
32/* Warn about undefined symbols? (do so if we have vmlinux) */
33int have_vmlinux = 0;
34/* Is CONFIG_MODULE_SRCVERSION_ALL set? */
35static int all_versions = 0;
36/* If we are modposting external module set to 1 */
37static int external_module = 0;
38/* Warn about section mismatch in vmlinux if set to 1 */
39static int vmlinux_section_warnings = 1;
40/* Only warn about unresolved symbols */
41static int warn_unresolved = 0;
42/* How a symbol is exported */
43static int sec_mismatch_count = 0;
44static int sec_mismatch_verbose = 1;
45
46enum export {
47 export_plain, export_unused, export_gpl,
48 export_unused_gpl, export_gpl_future, export_unknown
49};
50
51#define PRINTF __attribute__ ((format (printf, 1, 2)))
52
53PRINTF void fatal(const char *fmt, ...)
54{
55 va_list arglist;
56
57 fprintf(stderr, "FATAL: ");
58
59 va_start(arglist, fmt);
60 vfprintf(stderr, fmt, arglist);
61 va_end(arglist);
62
63 exit(1);
64}
65
66PRINTF void warn(const char *fmt, ...)
67{
68 va_list arglist;
69
70 fprintf(stderr, "WARNING: ");
71
72 va_start(arglist, fmt);
73 vfprintf(stderr, fmt, arglist);
74 va_end(arglist);
75}
76
77PRINTF void merror(const char *fmt, ...)
78{
79 va_list arglist;
80
81 fprintf(stderr, "ERROR: ");
82
83 va_start(arglist, fmt);
84 vfprintf(stderr, fmt, arglist);
85 va_end(arglist);
86}
87
88static int is_vmlinux(const char *modname)
89{
90 const char *myname;
91
92 myname = strrchr(modname, '/');
93 if (myname)
94 myname++;
95 else
96 myname = modname;
97
98 return (strcmp(myname, "vmlinux") == 0) ||
99 (strcmp(myname, "vmlinux.o") == 0);
100}
101
102void *do_nofail(void *ptr, const char *expr)
103{
104 if (!ptr)
105 fatal("modpost: Memory allocation failure: %s.\n", expr);
106
107 return ptr;
108}
109
110/* A list of all modules we processed */
111static struct module *modules;
112
113static struct module *find_module(char *modname)
114{
115 struct module *mod;
116
117 for (mod = modules; mod; mod = mod->next)
118 if (strcmp(mod->name, modname) == 0)
119 break;
120 return mod;
121}
122
123static struct module *new_module(char *modname)
124{
125 struct module *mod;
126 char *p, *s;
127
128 mod = NOFAIL(malloc(sizeof(*mod)));
129 memset(mod, 0, sizeof(*mod));
130 p = NOFAIL(strdup(modname));
131
132 /* strip trailing .o */
133 s = strrchr(p, '.');
134 if (s != NULL)
135 if (strcmp(s, ".o") == 0)
136 *s = '\0';
137
138 /* add to list */
139 mod->name = p;
140 mod->gpl_compatible = -1;
141 mod->next = modules;
142 modules = mod;
143
144 return mod;
145}
146
147/* A hash of all exported symbols,
148 * struct symbol is also used for lists of unresolved symbols */
149
150#define SYMBOL_HASH_SIZE 1024
151
152struct symbol {
153 struct symbol *next;
154 struct module *module;
155 unsigned int crc;
156 int crc_valid;
157 unsigned int weak:1;
158 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */
159 unsigned int kernel:1; /* 1 if symbol is from kernel
160 * (only for external modules) **/
161 unsigned int preloaded:1; /* 1 if symbol from Module.symvers */
162 enum export export; /* Type of export */
163 char name[0];
164};
165
166static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
167
168/* This is based on the hash agorithm from gdbm, via tdb */
169static inline unsigned int tdb_hash(const char *name)
170{
171 unsigned value; /* Used to compute the hash value. */
172 unsigned i; /* Used to cycle through random values. */
173
174 /* Set the initial value from the key size. */
175 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++)
176 value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
177
178 return (1103515243 * value + 12345);
179}
180
181/**
182 * Allocate a new symbols for use in the hash of exported symbols or
183 * the list of unresolved symbols per module
184 **/
185static struct symbol *alloc_symbol(const char *name, unsigned int weak,
186 struct symbol *next)
187{
188 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
189
190 memset(s, 0, sizeof(*s));
191 strcpy(s->name, name);
192 s->weak = weak;
193 s->next = next;
194 return s;
195}
196
197/* For the hash of exported symbols */
198static struct symbol *new_symbol(const char *name, struct module *module,
199 enum export export)
200{
201 unsigned int hash;
202 struct symbol *new;
203
204 hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
205 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
206 new->module = module;
207 new->export = export;
208 return new;
209}
210
211static struct symbol *find_symbol(const char *name)
212{
213 struct symbol *s;
214
215 /* For our purposes, .foo matches foo. PPC64 needs this. */
216 if (name[0] == '.')
217 name++;
218
219 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
220 if (strcmp(s->name, name) == 0)
221 return s;
222 }
223 return NULL;
224}
225
226static struct {
227 const char *str;
228 enum export export;
229} export_list[] = {
230 { .str = "EXPORT_SYMBOL", .export = export_plain },
231 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
232 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
233 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
234 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
235 { .str = "(unknown)", .export = export_unknown },
236};
237
238
239static const char *export_str(enum export ex)
240{
241 return export_list[ex].str;
242}
243
244static enum export export_no(const char *s)
245{
246 int i;
247
248 if (!s)
249 return export_unknown;
250 for (i = 0; export_list[i].export != export_unknown; i++) {
251 if (strcmp(export_list[i].str, s) == 0)
252 return export_list[i].export;
253 }
254 return export_unknown;
255}
256
257static const char *sec_name(struct elf_info *elf, int secindex);
258
259#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
260
261static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
262{
263 const char *secname = sec_name(elf, sec);
264
265 if (strstarts(secname, "___ksymtab+"))
266 return export_plain;
267 else if (strstarts(secname, "___ksymtab_unused+"))
268 return export_unused;
269 else if (strstarts(secname, "___ksymtab_gpl+"))
270 return export_gpl;
271 else if (strstarts(secname, "___ksymtab_unused_gpl+"))
272 return export_unused_gpl;
273 else if (strstarts(secname, "___ksymtab_gpl_future+"))
274 return export_gpl_future;
275 else
276 return export_unknown;
277}
278
279static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
280{
281 if (sec == elf->export_sec)
282 return export_plain;
283 else if (sec == elf->export_unused_sec)
284 return export_unused;
285 else if (sec == elf->export_gpl_sec)
286 return export_gpl;
287 else if (sec == elf->export_unused_gpl_sec)
288 return export_unused_gpl;
289 else if (sec == elf->export_gpl_future_sec)
290 return export_gpl_future;
291 else
292 return export_unknown;
293}
294
295/**
296 * Add an exported symbol - it may have already been added without a
297 * CRC, in this case just update the CRC
298 **/
299static struct symbol *sym_add_exported(const char *name, struct module *mod,
300 enum export export)
301{
302 struct symbol *s = find_symbol(name);
303
304 if (!s) {
305 s = new_symbol(name, mod, export);
306 } else {
307 if (!s->preloaded) {
308 warn("%s: '%s' exported twice. Previous export "
309 "was in %s%s\n", mod->name, name,
310 s->module->name,
311 is_vmlinux(s->module->name) ?"":".ko");
312 } else {
313 /* In case Modules.symvers was out of date */
314 s->module = mod;
315 }
316 }
317 s->preloaded = 0;
318 s->vmlinux = is_vmlinux(mod->name);
319 s->kernel = 0;
320 s->export = export;
321 return s;
322}
323
324static void sym_update_crc(const char *name, struct module *mod,
325 unsigned int crc, enum export export)
326{
327 struct symbol *s = find_symbol(name);
328
329 if (!s)
330 s = new_symbol(name, mod, export);
331 s->crc = crc;
332 s->crc_valid = 1;
333}
334
335void *grab_file(const char *filename, unsigned long *size)
336{
337 struct stat st;
338 void *map;
339 int fd;
340
341 fd = open(filename, O_RDONLY);
342 if (fd < 0 || fstat(fd, &st) != 0)
343 return NULL;
344
345 *size = st.st_size;
346 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
347 close(fd);
348
349 if (map == MAP_FAILED)
350 return NULL;
351 return map;
352}
353
354/**
355 * Return a copy of the next line in a mmap'ed file.
356 * spaces in the beginning of the line is trimmed away.
357 * Return a pointer to a static buffer.
358 **/
359char *get_next_line(unsigned long *pos, void *file, unsigned long size)
360{
361 static char line[4096];
362 int skip = 1;
363 size_t len = 0;
364 signed char *p = (signed char *)file + *pos;
365 char *s = line;
366
367 for (; *pos < size ; (*pos)++) {
368 if (skip && isspace(*p)) {
369 p++;
370 continue;
371 }
372 skip = 0;
373 if (*p != '\n' && (*pos < size)) {
374 len++;
375 *s++ = *p++;
376 if (len > 4095)
377 break; /* Too long, stop */
378 } else {
379 /* End of string */
380 *s = '\0';
381 return line;
382 }
383 }
384 /* End of buffer */
385 return NULL;
386}
387
388void release_file(void *file, unsigned long size)
389{
390 munmap(file, size);
391}
392
393static int parse_elf(struct elf_info *info, const char *filename)
394{
395 unsigned int i;
396 Elf_Ehdr *hdr;
397 Elf_Shdr *sechdrs;
398 Elf_Sym *sym;
399 const char *secstrings;
400 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
401
402 hdr = grab_file(filename, &info->size);
403 if (!hdr) {
404 perror(filename);
405 exit(1);
406 }
407 info->hdr = hdr;
408 if (info->size < sizeof(*hdr)) {
409 /* file too small, assume this is an empty .o file */
410 return 0;
411 }
412 /* Is this a valid ELF file? */
413 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
414 (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
415 (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
416 (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
417 /* Not an ELF file - silently ignore it */
418 return 0;
419 }
420 /* Fix endianness in ELF header */
421 hdr->e_type = TO_NATIVE(hdr->e_type);
422 hdr->e_machine = TO_NATIVE(hdr->e_machine);
423 hdr->e_version = TO_NATIVE(hdr->e_version);
424 hdr->e_entry = TO_NATIVE(hdr->e_entry);
425 hdr->e_phoff = TO_NATIVE(hdr->e_phoff);
426 hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
427 hdr->e_flags = TO_NATIVE(hdr->e_flags);
428 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize);
429 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
430 hdr->e_phnum = TO_NATIVE(hdr->e_phnum);
431 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
432 hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
433 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
434 sechdrs = (void *)hdr + hdr->e_shoff;
435 info->sechdrs = sechdrs;
436
437 /* Check if file offset is correct */
438 if (hdr->e_shoff > info->size) {
439 fatal("section header offset=%lu in file '%s' is bigger than "
440 "filesize=%lu\n", (unsigned long)hdr->e_shoff,
441 filename, info->size);
442 return 0;
443 }
444
445 if (hdr->e_shnum == SHN_UNDEF) {
446 /*
447 * There are more than 64k sections,
448 * read count from .sh_size.
449 */
450 info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
451 }
452 else {
453 info->num_sections = hdr->e_shnum;
454 }
455 if (hdr->e_shstrndx == SHN_XINDEX) {
456 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
457 }
458 else {
459 info->secindex_strings = hdr->e_shstrndx;
460 }
461
462 /* Fix endianness in section headers */
463 for (i = 0; i < info->num_sections; i++) {
464 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
465 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
466 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
467 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
468 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
469 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
470 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
471 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
472 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
473 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
474 }
475 /* Find symbol table. */
476 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
477 for (i = 1; i < info->num_sections; i++) {
478 const char *secname;
479 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
480
481 if (!nobits && sechdrs[i].sh_offset > info->size) {
482 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
483 "sizeof(*hrd)=%zu\n", filename,
484 (unsigned long)sechdrs[i].sh_offset,
485 sizeof(*hdr));
486 return 0;
487 }
488 secname = secstrings + sechdrs[i].sh_name;
489 if (strcmp(secname, ".modinfo") == 0) {
490 if (nobits)
491 fatal("%s has NOBITS .modinfo\n", filename);
492 info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
493 info->modinfo_len = sechdrs[i].sh_size;
494 } else if (strcmp(secname, "__ksymtab") == 0)
495 info->export_sec = i;
496 else if (strcmp(secname, "__ksymtab_unused") == 0)
497 info->export_unused_sec = i;
498 else if (strcmp(secname, "__ksymtab_gpl") == 0)
499 info->export_gpl_sec = i;
500 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
501 info->export_unused_gpl_sec = i;
502 else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
503 info->export_gpl_future_sec = i;
504
505 if (sechdrs[i].sh_type == SHT_SYMTAB) {
506 unsigned int sh_link_idx;
507 symtab_idx = i;
508 info->symtab_start = (void *)hdr +
509 sechdrs[i].sh_offset;
510 info->symtab_stop = (void *)hdr +
511 sechdrs[i].sh_offset + sechdrs[i].sh_size;
512 sh_link_idx = sechdrs[i].sh_link;
513 info->strtab = (void *)hdr +
514 sechdrs[sh_link_idx].sh_offset;
515 }
516
517 /* 32bit section no. table? ("more than 64k sections") */
518 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
519 symtab_shndx_idx = i;
520 info->symtab_shndx_start = (void *)hdr +
521 sechdrs[i].sh_offset;
522 info->symtab_shndx_stop = (void *)hdr +
523 sechdrs[i].sh_offset + sechdrs[i].sh_size;
524 }
525 }
526 if (!info->symtab_start)
527 fatal("%s has no symtab?\n", filename);
528
529 /* Fix endianness in symbols */
530 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
531 sym->st_shndx = TO_NATIVE(sym->st_shndx);
532 sym->st_name = TO_NATIVE(sym->st_name);
533 sym->st_value = TO_NATIVE(sym->st_value);
534 sym->st_size = TO_NATIVE(sym->st_size);
535 }
536
537 if (symtab_shndx_idx != ~0U) {
538 Elf32_Word *p;
539 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
540 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
541 filename, sechdrs[symtab_shndx_idx].sh_link,
542 symtab_idx);
543 /* Fix endianness */
544 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
545 p++)
546 *p = TO_NATIVE(*p);
547 }
548
549 return 1;
550}
551
552static void parse_elf_finish(struct elf_info *info)
553{
554 release_file(info->hdr, info->size);
555}
556
557static int ignore_undef_symbol(struct elf_info *info, const char *symname)
558{
559 /* ignore __this_module, it will be resolved shortly */
560 if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0)
561 return 1;
562 /* ignore global offset table */
563 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
564 return 1;
565 if (info->hdr->e_machine == EM_PPC)
566 /* Special register function linked on all modules during final link of .ko */
567 if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 ||
568 strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 ||
569 strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
570 strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0)
571 return 1;
572 if (info->hdr->e_machine == EM_PPC64)
573 /* Special register function linked on all modules during final link of .ko */
574 if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 ||
575 strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0)
576 return 1;
577 /* Do not ignore this symbol */
578 return 0;
579}
580
581#define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_"
582#define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
583
584static void handle_modversions(struct module *mod, struct elf_info *info,
585 Elf_Sym *sym, const char *symname)
586{
587 unsigned int crc;
588 enum export export;
589
590 if (!is_vmlinux(mod->name) && strncmp(symname, "__ksymtab", 9) == 0)
591 export = export_from_secname(info, get_secindex(info, sym));
592 else
593 export = export_from_sec(info, get_secindex(info, sym));
594
595 switch (sym->st_shndx) {
596 case SHN_COMMON:
597 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
598 break;
599 case SHN_ABS:
600 /* CRC'd symbol */
601 if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
602 crc = (unsigned int) sym->st_value;
603 sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
604 export);
605 }
606 break;
607 case SHN_UNDEF:
608 /* undefined symbol */
609 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
610 ELF_ST_BIND(sym->st_info) != STB_WEAK)
611 break;
612 if (ignore_undef_symbol(info, symname))
613 break;
614/* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
615#if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
616/* add compatibility with older glibc */
617#ifndef STT_SPARC_REGISTER
618#define STT_SPARC_REGISTER STT_REGISTER
619#endif
620 if (info->hdr->e_machine == EM_SPARC ||
621 info->hdr->e_machine == EM_SPARCV9) {
622 /* Ignore register directives. */
623 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
624 break;
625 if (symname[0] == '.') {
626 char *munged = strdup(symname);
627 munged[0] = '_';
628 munged[1] = toupper(munged[1]);
629 symname = munged;
630 }
631 }
632#endif
633
634 if (memcmp(symname, MODULE_SYMBOL_PREFIX,
635 strlen(MODULE_SYMBOL_PREFIX)) == 0) {
636 mod->unres =
637 alloc_symbol(symname +
638 strlen(MODULE_SYMBOL_PREFIX),
639 ELF_ST_BIND(sym->st_info) == STB_WEAK,
640 mod->unres);
641 }
642 break;
643 default:
644 /* All exported symbols */
645 if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
646 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
647 export);
648 }
649 if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
650 mod->has_init = 1;
651 if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0)
652 mod->has_cleanup = 1;
653 break;
654 }
655}
656
657/**
658 * Parse tag=value strings from .modinfo section
659 **/
660static char *next_string(char *string, unsigned long *secsize)
661{
662 /* Skip non-zero chars */
663 while (string[0]) {
664 string++;
665 if ((*secsize)-- <= 1)
666 return NULL;
667 }
668
669 /* Skip any zero padding. */
670 while (!string[0]) {
671 string++;
672 if ((*secsize)-- <= 1)
673 return NULL;
674 }
675 return string;
676}
677
678static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
679 const char *tag, char *info)
680{
681 char *p;
682 unsigned int taglen = strlen(tag);
683 unsigned long size = modinfo_len;
684
685 if (info) {
686 size -= info - (char *)modinfo;
687 modinfo = next_string(info, &size);
688 }
689
690 for (p = modinfo; p; p = next_string(p, &size)) {
691 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
692 return p + taglen + 1;
693 }
694 return NULL;
695}
696
697static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
698 const char *tag)
699
700{
701 return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
702}
703
704/**
705 * Test if string s ends in string sub
706 * return 0 if match
707 **/
708static int strrcmp(const char *s, const char *sub)
709{
710 int slen, sublen;
711
712 if (!s || !sub)
713 return 1;
714
715 slen = strlen(s);
716 sublen = strlen(sub);
717
718 if ((slen == 0) || (sublen == 0))
719 return 1;
720
721 if (sublen > slen)
722 return 1;
723
724 return memcmp(s + slen - sublen, sub, sublen);
725}
726
727static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
728{
729 if (sym)
730 return elf->strtab + sym->st_name;
731 else
732 return "(unknown)";
733}
734
735static const char *sec_name(struct elf_info *elf, int secindex)
736{
737 Elf_Shdr *sechdrs = elf->sechdrs;
738 return (void *)elf->hdr +
739 elf->sechdrs[elf->secindex_strings].sh_offset +
740 sechdrs[secindex].sh_name;
741}
742
743static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr)
744{
745 return (void *)elf->hdr +
746 elf->sechdrs[elf->secindex_strings].sh_offset +
747 sechdr->sh_name;
748}
749
750/* if sym is empty or point to a string
751 * like ".[0-9]+" then return 1.
752 * This is the optional prefix added by ld to some sections
753 */
754static int number_prefix(const char *sym)
755{
756 if (*sym++ == '\0')
757 return 1;
758 if (*sym != '.')
759 return 0;
760 do {
761 char c = *sym++;
762 if (c < '0' || c > '9')
763 return 0;
764 } while (*sym);
765 return 1;
766}
767
768/* The pattern is an array of simple patterns.
769 * "foo" will match an exact string equal to "foo"
770 * "*foo" will match a string that ends with "foo"
771 * "foo*" will match a string that begins with "foo"
772 * "foo$" will match a string equal to "foo" or "foo.1"
773 * where the '1' can be any number including several digits.
774 * The $ syntax is for sections where ld append a dot number
775 * to make section name unique.
776 */
777static int match(const char *sym, const char * const pat[])
778{
779 const char *p;
780 while (*pat) {
781 p = *pat++;
782 const char *endp = p + strlen(p) - 1;
783
784 /* "*foo" */
785 if (*p == '*') {
786 if (strrcmp(sym, p + 1) == 0)
787 return 1;
788 }
789 /* "foo*" */
790 else if (*endp == '*') {
791 if (strncmp(sym, p, strlen(p) - 1) == 0)
792 return 1;
793 }
794 /* "foo$" */
795 else if (*endp == '$') {
796 if (strncmp(sym, p, strlen(p) - 1) == 0) {
797 if (number_prefix(sym + strlen(p) - 1))
798 return 1;
799 }
800 }
801 /* no wildcards */
802 else {
803 if (strcmp(p, sym) == 0)
804 return 1;
805 }
806 }
807 /* no match */
808 return 0;
809}
810
811/* sections that we do not want to do full section mismatch check on */
812static const char *section_white_list[] =
813{
814 ".comment*",
815 ".debug*",
816 ".zdebug*", /* Compressed debug sections. */
817 ".GCC-command-line", /* mn10300 */
818 ".mdebug*", /* alpha, score, mips etc. */
819 ".pdr", /* alpha, score, mips etc. */
820 ".stab*",
821 ".note*",
822 ".got*",
823 ".toc*",
824 NULL
825};
826
827/*
828 * This is used to find sections missing the SHF_ALLOC flag.
829 * The cause of this is often a section specified in assembler
830 * without "ax" / "aw".
831 */
832static void check_section(const char *modname, struct elf_info *elf,
833 Elf_Shdr *sechdr)
834{
835 const char *sec = sech_name(elf, sechdr);
836
837 if (sechdr->sh_type == SHT_PROGBITS &&
838 !(sechdr->sh_flags & SHF_ALLOC) &&
839 !match(sec, section_white_list)) {
840 warn("%s (%s): unexpected non-allocatable section.\n"
841 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
842 "Note that for example <linux/init.h> contains\n"
843 "section definitions for use in .S files.\n\n",
844 modname, sec);
845 }
846}
847
848
849
850#define ALL_INIT_DATA_SECTIONS \
851 ".init.setup$", ".init.rodata$", \
852 ".devinit.rodata$", ".cpuinit.rodata$", ".meminit.rodata$", \
853 ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$"
854#define ALL_EXIT_DATA_SECTIONS \
855 ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$"
856
857#define ALL_INIT_TEXT_SECTIONS \
858 ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$"
859#define ALL_EXIT_TEXT_SECTIONS \
860 ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$"
861
862#define ALL_XXXINIT_SECTIONS DEV_INIT_SECTIONS, CPU_INIT_SECTIONS, \
863 MEM_INIT_SECTIONS
864#define ALL_XXXEXIT_SECTIONS DEV_EXIT_SECTIONS, CPU_EXIT_SECTIONS, \
865 MEM_EXIT_SECTIONS
866
867#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
868#define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
869
870#define DATA_SECTIONS ".data$", ".data.rel$"
871#define TEXT_SECTIONS ".text$"
872
873#define INIT_SECTIONS ".init.*"
874#define DEV_INIT_SECTIONS ".devinit.*"
875#define CPU_INIT_SECTIONS ".cpuinit.*"
876#define MEM_INIT_SECTIONS ".meminit.*"
877
878#define EXIT_SECTIONS ".exit.*"
879#define DEV_EXIT_SECTIONS ".devexit.*"
880#define CPU_EXIT_SECTIONS ".cpuexit.*"
881#define MEM_EXIT_SECTIONS ".memexit.*"
882
883/* init data sections */
884static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL };
885
886/* all init sections */
887static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL };
888
889/* All init and exit sections (code + data) */
890static const char *init_exit_sections[] =
891 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
892
893/* data section */
894static const char *data_sections[] = { DATA_SECTIONS, NULL };
895
896
897/* symbols in .data that may refer to init/exit sections */
898#define DEFAULT_SYMBOL_WHITE_LIST \
899 "*driver", \
900 "*_template", /* scsi uses *_template a lot */ \
901 "*_timer", /* arm uses ops structures named _timer a lot */ \
902 "*_sht", /* scsi also used *_sht to some extent */ \
903 "*_ops", \
904 "*_probe", \
905 "*_probe_one", \
906 "*_console"
907
908static const char *head_sections[] = { ".head.text*", NULL };
909static const char *linker_symbols[] =
910 { "__init_begin", "_sinittext", "_einittext", NULL };
911
912enum mismatch {
913 TEXT_TO_ANY_INIT,
914 DATA_TO_ANY_INIT,
915 TEXT_TO_ANY_EXIT,
916 DATA_TO_ANY_EXIT,
917 XXXINIT_TO_SOME_INIT,
918 XXXEXIT_TO_SOME_EXIT,
919 ANY_INIT_TO_ANY_EXIT,
920 ANY_EXIT_TO_ANY_INIT,
921 EXPORT_TO_INIT_EXIT,
922};
923
924struct sectioncheck {
925 const char *fromsec[20];
926 const char *tosec[20];
927 enum mismatch mismatch;
928 const char *symbol_white_list[20];
929};
930
931const struct sectioncheck sectioncheck[] = {
932/* Do not reference init/exit code/data from
933 * normal code and data
934 */
935{
936 .fromsec = { TEXT_SECTIONS, NULL },
937 .tosec = { ALL_INIT_SECTIONS, NULL },
938 .mismatch = TEXT_TO_ANY_INIT,
939 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
940},
941{
942 .fromsec = { DATA_SECTIONS, NULL },
943 .tosec = { ALL_XXXINIT_SECTIONS, NULL },
944 .mismatch = DATA_TO_ANY_INIT,
945 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
946},
947{
948 .fromsec = { DATA_SECTIONS, NULL },
949 .tosec = { INIT_SECTIONS, NULL },
950 .mismatch = DATA_TO_ANY_INIT,
951 .symbol_white_list = {
952 "*_template", "*_timer", "*_sht", "*_ops",
953 "*_probe", "*_probe_one", "*_console", NULL
954 },
955},
956{
957 .fromsec = { TEXT_SECTIONS, NULL },
958 .tosec = { ALL_EXIT_SECTIONS, NULL },
959 .mismatch = TEXT_TO_ANY_EXIT,
960 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
961},
962{
963 .fromsec = { DATA_SECTIONS, NULL },
964 .tosec = { ALL_EXIT_SECTIONS, NULL },
965 .mismatch = DATA_TO_ANY_EXIT,
966 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
967},
968/* Do not reference init code/data from devinit/cpuinit/meminit code/data */
969{
970 .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
971 .tosec = { INIT_SECTIONS, NULL },
972 .mismatch = XXXINIT_TO_SOME_INIT,
973 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
974},
975/* Do not reference cpuinit code/data from meminit code/data */
976{
977 .fromsec = { MEM_INIT_SECTIONS, NULL },
978 .tosec = { CPU_INIT_SECTIONS, NULL },
979 .mismatch = XXXINIT_TO_SOME_INIT,
980 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
981},
982/* Do not reference meminit code/data from cpuinit code/data */
983{
984 .fromsec = { CPU_INIT_SECTIONS, NULL },
985 .tosec = { MEM_INIT_SECTIONS, NULL },
986 .mismatch = XXXINIT_TO_SOME_INIT,
987 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
988},
989/* Do not reference exit code/data from devexit/cpuexit/memexit code/data */
990{
991 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
992 .tosec = { EXIT_SECTIONS, NULL },
993 .mismatch = XXXEXIT_TO_SOME_EXIT,
994 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
995},
996/* Do not reference cpuexit code/data from memexit code/data */
997{
998 .fromsec = { MEM_EXIT_SECTIONS, NULL },
999 .tosec = { CPU_EXIT_SECTIONS, NULL },
1000 .mismatch = XXXEXIT_TO_SOME_EXIT,
1001 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1002},
1003/* Do not reference memexit code/data from cpuexit code/data */
1004{
1005 .fromsec = { CPU_EXIT_SECTIONS, NULL },
1006 .tosec = { MEM_EXIT_SECTIONS, NULL },
1007 .mismatch = XXXEXIT_TO_SOME_EXIT,
1008 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1009},
1010/* Do not use exit code/data from init code */
1011{
1012 .fromsec = { ALL_INIT_SECTIONS, NULL },
1013 .tosec = { ALL_EXIT_SECTIONS, NULL },
1014 .mismatch = ANY_INIT_TO_ANY_EXIT,
1015 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1016},
1017/* Do not use init code/data from exit code */
1018{
1019 .fromsec = { ALL_EXIT_SECTIONS, NULL },
1020 .tosec = { ALL_INIT_SECTIONS, NULL },
1021 .mismatch = ANY_EXIT_TO_ANY_INIT,
1022 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1023},
1024/* Do not export init/exit functions or data */
1025{
1026 .fromsec = { "__ksymtab*", NULL },
1027 .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
1028 .mismatch = EXPORT_TO_INIT_EXIT,
1029 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1030}
1031};
1032
1033static const struct sectioncheck *section_mismatch(
1034 const char *fromsec, const char *tosec)
1035{
1036 int i;
1037 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
1038 const struct sectioncheck *check = &sectioncheck[0];
1039
1040 for (i = 0; i < elems; i++) {
1041 if (match(fromsec, check->fromsec) &&
1042 match(tosec, check->tosec))
1043 return check;
1044 check++;
1045 }
1046 return NULL;
1047}
1048
1049/**
1050 * Whitelist to allow certain references to pass with no warning.
1051 *
1052 * Pattern 1:
1053 * If a module parameter is declared __initdata and permissions=0
1054 * then this is legal despite the warning generated.
1055 * We cannot see value of permissions here, so just ignore
1056 * this pattern.
1057 * The pattern is identified by:
1058 * tosec = .init.data
1059 * fromsec = .data*
1060 * atsym =__param*
1061 *
1062 * Pattern 1a:
1063 * module_param_call() ops can refer to __init set function if permissions=0
1064 * The pattern is identified by:
1065 * tosec = .init.text
1066 * fromsec = .data*
1067 * atsym = __param_ops_*
1068 *
1069 * Pattern 2:
1070 * Many drivers utilise a *driver container with references to
1071 * add, remove, probe functions etc.
1072 * These functions may often be marked __devinit and we do not want to
1073 * warn here.
1074 * the pattern is identified by:
1075 * tosec = init or exit section
1076 * fromsec = data section
1077 * atsym = *driver, *_template, *_sht, *_ops, *_probe,
1078 * *probe_one, *_console, *_timer
1079 *
1080 * Pattern 3:
1081 * Whitelist all references from .head.text to any init section
1082 *
1083 * Pattern 4:
1084 * Some symbols belong to init section but still it is ok to reference
1085 * these from non-init sections as these symbols don't have any memory
1086 * allocated for them and symbol address and value are same. So even
1087 * if init section is freed, its ok to reference those symbols.
1088 * For ex. symbols marking the init section boundaries.
1089 * This pattern is identified by
1090 * refsymname = __init_begin, _sinittext, _einittext
1091 *
1092 **/
1093static int secref_whitelist(const struct sectioncheck *mismatch,
1094 const char *fromsec, const char *fromsym,
1095 const char *tosec, const char *tosym)
1096{
1097 /* Check for pattern 1 */
1098 if (match(tosec, init_data_sections) &&
1099 match(fromsec, data_sections) &&
1100 (strncmp(fromsym, "__param", strlen("__param")) == 0))
1101 return 0;
1102
1103 /* Check for pattern 1a */
1104 if (strcmp(tosec, ".init.text") == 0 &&
1105 match(fromsec, data_sections) &&
1106 (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0))
1107 return 0;
1108
1109 /* Check for pattern 2 */
1110 if (match(tosec, init_exit_sections) &&
1111 match(fromsec, data_sections) &&
1112 match(fromsym, mismatch->symbol_white_list))
1113 return 0;
1114
1115 /* Check for pattern 3 */
1116 if (match(fromsec, head_sections) &&
1117 match(tosec, init_sections))
1118 return 0;
1119
1120 /* Check for pattern 4 */
1121 if (match(tosym, linker_symbols))
1122 return 0;
1123
1124 return 1;
1125}
1126
1127/**
1128 * Find symbol based on relocation record info.
1129 * In some cases the symbol supplied is a valid symbol so
1130 * return refsym. If st_name != 0 we assume this is a valid symbol.
1131 * In other cases the symbol needs to be looked up in the symbol table
1132 * based on section and address.
1133 * **/
1134static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
1135 Elf_Sym *relsym)
1136{
1137 Elf_Sym *sym;
1138 Elf_Sym *near = NULL;
1139 Elf64_Sword distance = 20;
1140 Elf64_Sword d;
1141 unsigned int relsym_secindex;
1142
1143 if (relsym->st_name != 0)
1144 return relsym;
1145
1146 relsym_secindex = get_secindex(elf, relsym);
1147 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1148 if (get_secindex(elf, sym) != relsym_secindex)
1149 continue;
1150 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
1151 continue;
1152 if (sym->st_value == addr)
1153 return sym;
1154 /* Find a symbol nearby - addr are maybe negative */
1155 d = sym->st_value - addr;
1156 if (d < 0)
1157 d = addr - sym->st_value;
1158 if (d < distance) {
1159 distance = d;
1160 near = sym;
1161 }
1162 }
1163 /* We need a close match */
1164 if (distance < 20)
1165 return near;
1166 else
1167 return NULL;
1168}
1169
1170static inline int is_arm_mapping_symbol(const char *str)
1171{
1172 return str[0] == '$' && strchr("atd", str[1])
1173 && (str[2] == '\0' || str[2] == '.');
1174}
1175
1176/*
1177 * If there's no name there, ignore it; likewise, ignore it if it's
1178 * one of the magic symbols emitted used by current ARM tools.
1179 *
1180 * Otherwise if find_symbols_between() returns those symbols, they'll
1181 * fail the whitelist tests and cause lots of false alarms ... fixable
1182 * only by merging __exit and __init sections into __text, bloating
1183 * the kernel (which is especially evil on embedded platforms).
1184 */
1185static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
1186{
1187 const char *name = elf->strtab + sym->st_name;
1188
1189 if (!name || !strlen(name))
1190 return 0;
1191 return !is_arm_mapping_symbol(name);
1192}
1193
1194/*
1195 * Find symbols before or equal addr and after addr - in the section sec.
1196 * If we find two symbols with equal offset prefer one with a valid name.
1197 * The ELF format may have a better way to detect what type of symbol
1198 * it is, but this works for now.
1199 **/
1200static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
1201 const char *sec)
1202{
1203 Elf_Sym *sym;
1204 Elf_Sym *near = NULL;
1205 Elf_Addr distance = ~0;
1206
1207 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1208 const char *symsec;
1209
1210 if (is_shndx_special(sym->st_shndx))
1211 continue;
1212 symsec = sec_name(elf, get_secindex(elf, sym));
1213 if (strcmp(symsec, sec) != 0)
1214 continue;
1215 if (!is_valid_name(elf, sym))
1216 continue;
1217 if (sym->st_value <= addr) {
1218 if ((addr - sym->st_value) < distance) {
1219 distance = addr - sym->st_value;
1220 near = sym;
1221 } else if ((addr - sym->st_value) == distance) {
1222 near = sym;
1223 }
1224 }
1225 }
1226 return near;
1227}
1228
1229/*
1230 * Convert a section name to the function/data attribute
1231 * .init.text => __init
1232 * .cpuinit.data => __cpudata
1233 * .memexitconst => __memconst
1234 * etc.
1235 *
1236 * The memory of returned value has been allocated on a heap. The user of this
1237 * method should free it after usage.
1238*/
1239static char *sec2annotation(const char *s)
1240{
1241 if (match(s, init_exit_sections)) {
1242 char *p = malloc(20);
1243 char *r = p;
1244
1245 *p++ = '_';
1246 *p++ = '_';
1247 if (*s == '.')
1248 s++;
1249 while (*s && *s != '.')
1250 *p++ = *s++;
1251 *p = '\0';
1252 if (*s == '.')
1253 s++;
1254 if (strstr(s, "rodata") != NULL)
1255 strcat(p, "const ");
1256 else if (strstr(s, "data") != NULL)
1257 strcat(p, "data ");
1258 else
1259 strcat(p, " ");
1260 return r;
1261 } else {
1262 return strdup("");
1263 }
1264}
1265
1266static int is_function(Elf_Sym *sym)
1267{
1268 if (sym)
1269 return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
1270 else
1271 return -1;
1272}
1273
1274static void print_section_list(const char * const list[20])
1275{
1276 const char *const *s = list;
1277
1278 while (*s) {
1279 fprintf(stderr, "%s", *s);
1280 s++;
1281 if (*s)
1282 fprintf(stderr, ", ");
1283 }
1284 fprintf(stderr, "\n");
1285}
1286
1287/*
1288 * Print a warning about a section mismatch.
1289 * Try to find symbols near it so user can find it.
1290 * Check whitelist before warning - it may be a false positive.
1291 */
1292static void report_sec_mismatch(const char *modname,
1293 const struct sectioncheck *mismatch,
1294 const char *fromsec,
1295 unsigned long long fromaddr,
1296 const char *fromsym,
1297 int from_is_func,
1298 const char *tosec, const char *tosym,
1299 int to_is_func)
1300{
1301 const char *from, *from_p;
1302 const char *to, *to_p;
1303 char *prl_from;
1304 char *prl_to;
1305
1306 switch (from_is_func) {
1307 case 0: from = "variable"; from_p = ""; break;
1308 case 1: from = "function"; from_p = "()"; break;
1309 default: from = "(unknown reference)"; from_p = ""; break;
1310 }
1311 switch (to_is_func) {
1312 case 0: to = "variable"; to_p = ""; break;
1313 case 1: to = "function"; to_p = "()"; break;
1314 default: to = "(unknown reference)"; to_p = ""; break;
1315 }
1316
1317 sec_mismatch_count++;
1318 if (!sec_mismatch_verbose)
1319 return;
1320
1321 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1322 "to the %s %s:%s%s\n",
1323 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
1324 tosym, to_p);
1325
1326 switch (mismatch->mismatch) {
1327 case TEXT_TO_ANY_INIT:
1328 prl_from = sec2annotation(fromsec);
1329 prl_to = sec2annotation(tosec);
1330 fprintf(stderr,
1331 "The function %s%s() references\n"
1332 "the %s %s%s%s.\n"
1333 "This is often because %s lacks a %s\n"
1334 "annotation or the annotation of %s is wrong.\n",
1335 prl_from, fromsym,
1336 to, prl_to, tosym, to_p,
1337 fromsym, prl_to, tosym);
1338 free(prl_from);
1339 free(prl_to);
1340 break;
1341 case DATA_TO_ANY_INIT: {
1342 prl_to = sec2annotation(tosec);
1343 fprintf(stderr,
1344 "The variable %s references\n"
1345 "the %s %s%s%s\n"
1346 "If the reference is valid then annotate the\n"
1347 "variable with __init* or __refdata (see linux/init.h) "
1348 "or name the variable:\n",
1349 fromsym, to, prl_to, tosym, to_p);
1350 print_section_list(mismatch->symbol_white_list);
1351 free(prl_to);
1352 break;
1353 }
1354 case TEXT_TO_ANY_EXIT:
1355 prl_to = sec2annotation(tosec);
1356 fprintf(stderr,
1357 "The function %s() references a %s in an exit section.\n"
1358 "Often the %s %s%s has valid usage outside the exit section\n"
1359 "and the fix is to remove the %sannotation of %s.\n",
1360 fromsym, to, to, tosym, to_p, prl_to, tosym);
1361 free(prl_to);
1362 break;
1363 case DATA_TO_ANY_EXIT: {
1364 prl_to = sec2annotation(tosec);
1365 fprintf(stderr,
1366 "The variable %s references\n"
1367 "the %s %s%s%s\n"
1368 "If the reference is valid then annotate the\n"
1369 "variable with __exit* (see linux/init.h) or "
1370 "name the variable:\n",
1371 fromsym, to, prl_to, tosym, to_p);
1372 print_section_list(mismatch->symbol_white_list);
1373 free(prl_to);
1374 break;
1375 }
1376 case XXXINIT_TO_SOME_INIT:
1377 case XXXEXIT_TO_SOME_EXIT:
1378 prl_from = sec2annotation(fromsec);
1379 prl_to = sec2annotation(tosec);
1380 fprintf(stderr,
1381 "The %s %s%s%s references\n"
1382 "a %s %s%s%s.\n"
1383 "If %s is only used by %s then\n"
1384 "annotate %s with a matching annotation.\n",
1385 from, prl_from, fromsym, from_p,
1386 to, prl_to, tosym, to_p,
1387 tosym, fromsym, tosym);
1388 free(prl_from);
1389 free(prl_to);
1390 break;
1391 case ANY_INIT_TO_ANY_EXIT:
1392 prl_from = sec2annotation(fromsec);
1393 prl_to = sec2annotation(tosec);
1394 fprintf(stderr,
1395 "The %s %s%s%s references\n"
1396 "a %s %s%s%s.\n"
1397 "This is often seen when error handling "
1398 "in the init function\n"
1399 "uses functionality in the exit path.\n"
1400 "The fix is often to remove the %sannotation of\n"
1401 "%s%s so it may be used outside an exit section.\n",
1402 from, prl_from, fromsym, from_p,
1403 to, prl_to, tosym, to_p,
1404 prl_to, tosym, to_p);
1405 free(prl_from);
1406 free(prl_to);
1407 break;
1408 case ANY_EXIT_TO_ANY_INIT:
1409 prl_from = sec2annotation(fromsec);
1410 prl_to = sec2annotation(tosec);
1411 fprintf(stderr,
1412 "The %s %s%s%s references\n"
1413 "a %s %s%s%s.\n"
1414 "This is often seen when error handling "
1415 "in the exit function\n"
1416 "uses functionality in the init path.\n"
1417 "The fix is often to remove the %sannotation of\n"
1418 "%s%s so it may be used outside an init section.\n",
1419 from, prl_from, fromsym, from_p,
1420 to, prl_to, tosym, to_p,
1421 prl_to, tosym, to_p);
1422 free(prl_from);
1423 free(prl_to);
1424 break;
1425 case EXPORT_TO_INIT_EXIT:
1426 prl_to = sec2annotation(tosec);
1427 fprintf(stderr,
1428 "The symbol %s is exported and annotated %s\n"
1429 "Fix this by removing the %sannotation of %s "
1430 "or drop the export.\n",
1431 tosym, prl_to, prl_to, tosym);
1432 free(prl_to);
1433 break;
1434 }
1435 fprintf(stderr, "\n");
1436}
1437
1438static void check_section_mismatch(const char *modname, struct elf_info *elf,
1439 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1440{
1441 const char *tosec;
1442 const struct sectioncheck *mismatch;
1443
1444 tosec = sec_name(elf, get_secindex(elf, sym));
1445 mismatch = section_mismatch(fromsec, tosec);
1446 if (mismatch) {
1447 Elf_Sym *to;
1448 Elf_Sym *from;
1449 const char *tosym;
1450 const char *fromsym;
1451
1452 from = find_elf_symbol2(elf, r->r_offset, fromsec);
1453 fromsym = sym_name(elf, from);
1454 to = find_elf_symbol(elf, r->r_addend, sym);
1455 tosym = sym_name(elf, to);
1456
1457 /* check whitelist - we may ignore it */
1458 if (secref_whitelist(mismatch,
1459 fromsec, fromsym, tosec, tosym)) {
1460 report_sec_mismatch(modname, mismatch,
1461 fromsec, r->r_offset, fromsym,
1462 is_function(from), tosec, tosym,
1463 is_function(to));
1464 }
1465 }
1466}
1467
1468static unsigned int *reloc_location(struct elf_info *elf,
1469 Elf_Shdr *sechdr, Elf_Rela *r)
1470{
1471 Elf_Shdr *sechdrs = elf->sechdrs;
1472 int section = sechdr->sh_info;
1473
1474 return (void *)elf->hdr + sechdrs[section].sh_offset +
1475 r->r_offset;
1476}
1477
1478static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1479{
1480 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1481 unsigned int *location = reloc_location(elf, sechdr, r);
1482
1483 switch (r_typ) {
1484 case R_386_32:
1485 r->r_addend = TO_NATIVE(*location);
1486 break;
1487 case R_386_PC32:
1488 r->r_addend = TO_NATIVE(*location) + 4;
1489 /* For CONFIG_RELOCATABLE=y */
1490 if (elf->hdr->e_type == ET_EXEC)
1491 r->r_addend += r->r_offset;
1492 break;
1493 }
1494 return 0;
1495}
1496
1497#ifndef R_ARM_CALL
1498#define R_ARM_CALL 28
1499#endif
1500#ifndef R_ARM_JUMP24
1501#define R_ARM_JUMP24 29
1502#endif
1503
1504static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1505{
1506 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1507
1508 switch (r_typ) {
1509 case R_ARM_ABS32:
1510 /* From ARM ABI: (S + A) | T */
1511 r->r_addend = (int)(long)
1512 (elf->symtab_start + ELF_R_SYM(r->r_info));
1513 break;
1514 case R_ARM_PC24:
1515 case R_ARM_CALL:
1516 case R_ARM_JUMP24:
1517 /* From ARM ABI: ((S + A) | T) - P */
1518 r->r_addend = (int)(long)(elf->hdr +
1519 sechdr->sh_offset +
1520 (r->r_offset - sechdr->sh_addr));
1521 break;
1522 default:
1523 return 1;
1524 }
1525 return 0;
1526}
1527
1528static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1529{
1530 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1531 unsigned int *location = reloc_location(elf, sechdr, r);
1532 unsigned int inst;
1533
1534 if (r_typ == R_MIPS_HI16)
1535 return 1; /* skip this */
1536 inst = TO_NATIVE(*location);
1537 switch (r_typ) {
1538 case R_MIPS_LO16:
1539 r->r_addend = inst & 0xffff;
1540 break;
1541 case R_MIPS_26:
1542 r->r_addend = (inst & 0x03ffffff) << 2;
1543 break;
1544 case R_MIPS_32:
1545 r->r_addend = inst;
1546 break;
1547 }
1548 return 0;
1549}
1550
1551static void section_rela(const char *modname, struct elf_info *elf,
1552 Elf_Shdr *sechdr)
1553{
1554 Elf_Sym *sym;
1555 Elf_Rela *rela;
1556 Elf_Rela r;
1557 unsigned int r_sym;
1558 const char *fromsec;
1559
1560 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
1561 Elf_Rela *stop = (void *)start + sechdr->sh_size;
1562
1563 fromsec = sech_name(elf, sechdr);
1564 fromsec += strlen(".rela");
1565 /* if from section (name) is know good then skip it */
1566 if (match(fromsec, section_white_list))
1567 return;
1568
1569 for (rela = start; rela < stop; rela++) {
1570 r.r_offset = TO_NATIVE(rela->r_offset);
1571#if KERNEL_ELFCLASS == ELFCLASS64
1572 if (elf->hdr->e_machine == EM_MIPS) {
1573 unsigned int r_typ;
1574 r_sym = ELF64_MIPS_R_SYM(rela->r_info);
1575 r_sym = TO_NATIVE(r_sym);
1576 r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
1577 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1578 } else {
1579 r.r_info = TO_NATIVE(rela->r_info);
1580 r_sym = ELF_R_SYM(r.r_info);
1581 }
1582#else
1583 r.r_info = TO_NATIVE(rela->r_info);
1584 r_sym = ELF_R_SYM(r.r_info);
1585#endif
1586 r.r_addend = TO_NATIVE(rela->r_addend);
1587 sym = elf->symtab_start + r_sym;
1588 /* Skip special sections */
1589 if (is_shndx_special(sym->st_shndx))
1590 continue;
1591 check_section_mismatch(modname, elf, &r, sym, fromsec);
1592 }
1593}
1594
1595static void section_rel(const char *modname, struct elf_info *elf,
1596 Elf_Shdr *sechdr)
1597{
1598 Elf_Sym *sym;
1599 Elf_Rel *rel;
1600 Elf_Rela r;
1601 unsigned int r_sym;
1602 const char *fromsec;
1603
1604 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
1605 Elf_Rel *stop = (void *)start + sechdr->sh_size;
1606
1607 fromsec = sech_name(elf, sechdr);
1608 fromsec += strlen(".rel");
1609 /* if from section (name) is know good then skip it */
1610 if (match(fromsec, section_white_list))
1611 return;
1612
1613 for (rel = start; rel < stop; rel++) {
1614 r.r_offset = TO_NATIVE(rel->r_offset);
1615#if KERNEL_ELFCLASS == ELFCLASS64
1616 if (elf->hdr->e_machine == EM_MIPS) {
1617 unsigned int r_typ;
1618 r_sym = ELF64_MIPS_R_SYM(rel->r_info);
1619 r_sym = TO_NATIVE(r_sym);
1620 r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
1621 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1622 } else {
1623 r.r_info = TO_NATIVE(rel->r_info);
1624 r_sym = ELF_R_SYM(r.r_info);
1625 }
1626#else
1627 r.r_info = TO_NATIVE(rel->r_info);
1628 r_sym = ELF_R_SYM(r.r_info);
1629#endif
1630 r.r_addend = 0;
1631 switch (elf->hdr->e_machine) {
1632 case EM_386:
1633 if (addend_386_rel(elf, sechdr, &r))
1634 continue;
1635 break;
1636 case EM_ARM:
1637 if (addend_arm_rel(elf, sechdr, &r))
1638 continue;
1639 break;
1640 case EM_MIPS:
1641 if (addend_mips_rel(elf, sechdr, &r))
1642 continue;
1643 break;
1644 }
1645 sym = elf->symtab_start + r_sym;
1646 /* Skip special sections */
1647 if (is_shndx_special(sym->st_shndx))
1648 continue;
1649 check_section_mismatch(modname, elf, &r, sym, fromsec);
1650 }
1651}
1652
1653/**
1654 * A module includes a number of sections that are discarded
1655 * either when loaded or when used as built-in.
1656 * For loaded modules all functions marked __init and all data
1657 * marked __initdata will be discarded when the module has been initialized.
1658 * Likewise for modules used built-in the sections marked __exit
1659 * are discarded because __exit marked function are supposed to be called
1660 * only when a module is unloaded which never happens for built-in modules.
1661 * The check_sec_ref() function traverses all relocation records
1662 * to find all references to a section that reference a section that will
1663 * be discarded and warns about it.
1664 **/
1665static void check_sec_ref(struct module *mod, const char *modname,
1666 struct elf_info *elf)
1667{
1668 int i;
1669 Elf_Shdr *sechdrs = elf->sechdrs;
1670
1671 /* Walk through all sections */
1672 for (i = 0; i < elf->num_sections; i++) {
1673 check_section(modname, elf, &elf->sechdrs[i]);
1674 /* We want to process only relocation sections and not .init */
1675 if (sechdrs[i].sh_type == SHT_RELA)
1676 section_rela(modname, elf, &elf->sechdrs[i]);
1677 else if (sechdrs[i].sh_type == SHT_REL)
1678 section_rel(modname, elf, &elf->sechdrs[i]);
1679 }
1680}
1681
1682static void read_symbols(char *modname)
1683{
1684 const char *symname;
1685 char *version;
1686 char *license;
1687 struct module *mod;
1688 struct elf_info info = { };
1689 Elf_Sym *sym;
1690
1691 if (!parse_elf(&info, modname))
1692 return;
1693
1694 mod = new_module(modname);
1695
1696 /* When there's no vmlinux, don't print warnings about
1697 * unresolved symbols (since there'll be too many ;) */
1698 if (is_vmlinux(modname)) {
1699 have_vmlinux = 1;
1700 mod->skip = 1;
1701 }
1702
1703 license = get_modinfo(info.modinfo, info.modinfo_len, "license");
1704 if (info.modinfo && !license && !is_vmlinux(modname))
1705 warn("modpost: missing MODULE_LICENSE() in %s\n"
1706 "see include/linux/module.h for "
1707 "more information\n", modname);
1708 while (license) {
1709 if (license_is_gpl_compatible(license))
1710 mod->gpl_compatible = 1;
1711 else {
1712 mod->gpl_compatible = 0;
1713 break;
1714 }
1715 license = get_next_modinfo(info.modinfo, info.modinfo_len,
1716 "license", license);
1717 }
1718
1719 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
1720 symname = info.strtab + sym->st_name;
1721
1722 handle_modversions(mod, &info, sym, symname);
1723 handle_moddevtable(mod, &info, sym, symname);
1724 }
1725 if (!is_vmlinux(modname) ||
1726 (is_vmlinux(modname) && vmlinux_section_warnings))
1727 check_sec_ref(mod, modname, &info);
1728
1729 version = get_modinfo(info.modinfo, info.modinfo_len, "version");
1730 if (version)
1731 maybe_frob_rcs_version(modname, version, info.modinfo,
1732 version - (char *)info.hdr);
1733 if (version || (all_versions && !is_vmlinux(modname)))
1734 get_src_version(modname, mod->srcversion,
1735 sizeof(mod->srcversion)-1);
1736
1737 parse_elf_finish(&info);
1738
1739 /* Our trick to get versioning for module struct etc. - it's
1740 * never passed as an argument to an exported function, so
1741 * the automatic versioning doesn't pick it up, but it's really
1742 * important anyhow */
1743 if (modversions)
1744 mod->unres = alloc_symbol("module_layout", 0, mod->unres);
1745}
1746
1747#define SZ 500
1748
1749/* We first write the generated file into memory using the
1750 * following helper, then compare to the file on disk and
1751 * only update the later if anything changed */
1752
1753void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
1754 const char *fmt, ...)
1755{
1756 char tmp[SZ];
1757 int len;
1758 va_list ap;
1759
1760 va_start(ap, fmt);
1761 len = vsnprintf(tmp, SZ, fmt, ap);
1762 buf_write(buf, tmp, len);
1763 va_end(ap);
1764}
1765
1766void buf_write(struct buffer *buf, const char *s, int len)
1767{
1768 if (buf->size - buf->pos < len) {
1769 buf->size += len + SZ;
1770 buf->p = realloc(buf->p, buf->size);
1771 }
1772 strncpy(buf->p + buf->pos, s, len);
1773 buf->pos += len;
1774}
1775
1776static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
1777{
1778 const char *e = is_vmlinux(m) ?"":".ko";
1779
1780 switch (exp) {
1781 case export_gpl:
1782 fatal("modpost: GPL-incompatible module %s%s "
1783 "uses GPL-only symbol '%s'\n", m, e, s);
1784 break;
1785 case export_unused_gpl:
1786 fatal("modpost: GPL-incompatible module %s%s "
1787 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
1788 break;
1789 case export_gpl_future:
1790 warn("modpost: GPL-incompatible module %s%s "
1791 "uses future GPL-only symbol '%s'\n", m, e, s);
1792 break;
1793 case export_plain:
1794 case export_unused:
1795 case export_unknown:
1796 /* ignore */
1797 break;
1798 }
1799}
1800
1801static void check_for_unused(enum export exp, const char *m, const char *s)
1802{
1803 const char *e = is_vmlinux(m) ?"":".ko";
1804
1805 switch (exp) {
1806 case export_unused:
1807 case export_unused_gpl:
1808 warn("modpost: module %s%s "
1809 "uses symbol '%s' marked UNUSED\n", m, e, s);
1810 break;
1811 default:
1812 /* ignore */
1813 break;
1814 }
1815}
1816
1817static void check_exports(struct module *mod)
1818{
1819 struct symbol *s, *exp;
1820
1821 for (s = mod->unres; s; s = s->next) {
1822 const char *basename;
1823 exp = find_symbol(s->name);
1824 if (!exp || exp->module == mod)
1825 continue;
1826 basename = strrchr(mod->name, '/');
1827 if (basename)
1828 basename++;
1829 else
1830 basename = mod->name;
1831 if (!mod->gpl_compatible)
1832 check_for_gpl_usage(exp->export, basename, exp->name);
1833 check_for_unused(exp->export, basename, exp->name);
1834 }
1835}
1836
1837/**
1838 * Header for the generated file
1839 **/
1840static void add_header(struct buffer *b, struct module *mod)
1841{
1842 buf_printf(b, "#include <linux/module.h>\n");
1843 buf_printf(b, "#include <linux/vermagic.h>\n");
1844 buf_printf(b, "#include <linux/compiler.h>\n");
1845 buf_printf(b, "\n");
1846 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1847 buf_printf(b, "\n");
1848 buf_printf(b, "struct module __this_module\n");
1849 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
1850 buf_printf(b, " .name = KBUILD_MODNAME,\n");
1851 if (mod->has_init)
1852 buf_printf(b, " .init = init_module,\n");
1853 if (mod->has_cleanup)
1854 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
1855 " .exit = cleanup_module,\n"
1856 "#endif\n");
1857 buf_printf(b, " .arch = MODULE_ARCH_INIT,\n");
1858 buf_printf(b, "};\n");
1859}
1860
1861static void add_intree_flag(struct buffer *b, int is_intree)
1862{
1863 if (is_intree)
1864 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
1865}
1866
1867static void add_staging_flag(struct buffer *b, const char *name)
1868{
1869 static const char *staging_dir = "drivers/staging";
1870
1871 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0)
1872 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
1873}
1874
1875/**
1876 * Record CRCs for unresolved symbols
1877 **/
1878static int add_versions(struct buffer *b, struct module *mod)
1879{
1880 struct symbol *s, *exp;
1881 int err = 0;
1882
1883 for (s = mod->unres; s; s = s->next) {
1884 exp = find_symbol(s->name);
1885 if (!exp || exp->module == mod) {
1886 if (have_vmlinux && !s->weak) {
1887 if (warn_unresolved) {
1888 warn("\"%s\" [%s.ko] undefined!\n",
1889 s->name, mod->name);
1890 } else {
1891 merror("\"%s\" [%s.ko] undefined!\n",
1892 s->name, mod->name);
1893 err = 1;
1894 }
1895 }
1896 continue;
1897 }
1898 s->module = exp->module;
1899 s->crc_valid = exp->crc_valid;
1900 s->crc = exp->crc;
1901 }
1902
1903 if (!modversions)
1904 return err;
1905
1906 buf_printf(b, "\n");
1907 buf_printf(b, "static const struct modversion_info ____versions[]\n");
1908 buf_printf(b, "__used\n");
1909 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n");
1910
1911 for (s = mod->unres; s; s = s->next) {
1912 if (!s->module)
1913 continue;
1914 if (!s->crc_valid) {
1915 warn("\"%s\" [%s.ko] has no CRC!\n",
1916 s->name, mod->name);
1917 continue;
1918 }
1919 buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name);
1920 }
1921
1922 buf_printf(b, "};\n");
1923
1924 return err;
1925}
1926
1927static void add_depends(struct buffer *b, struct module *mod,
1928 struct module *modules)
1929{
1930 struct symbol *s;
1931 struct module *m;
1932 int first = 1;
1933
1934 for (m = modules; m; m = m->next)
1935 m->seen = is_vmlinux(m->name);
1936
1937 buf_printf(b, "\n");
1938 buf_printf(b, "static const char __module_depends[]\n");
1939 buf_printf(b, "__used\n");
1940 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n");
1941 buf_printf(b, "\"depends=");
1942 for (s = mod->unres; s; s = s->next) {
1943 const char *p;
1944 if (!s->module)
1945 continue;
1946
1947 if (s->module->seen)
1948 continue;
1949
1950 s->module->seen = 1;
1951 p = strrchr(s->module->name, '/');
1952 if (p)
1953 p++;
1954 else
1955 p = s->module->name;
1956 buf_printf(b, "%s%s", first ? "" : ",", p);
1957 first = 0;
1958 }
1959 buf_printf(b, "\";\n");
1960}
1961
1962static void add_srcversion(struct buffer *b, struct module *mod)
1963{
1964 if (mod->srcversion[0]) {
1965 buf_printf(b, "\n");
1966 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
1967 mod->srcversion);
1968 }
1969}
1970
1971static void write_if_changed(struct buffer *b, const char *fname)
1972{
1973 char *tmp;
1974 FILE *file;
1975 struct stat st;
1976
1977 file = fopen(fname, "r");
1978 if (!file)
1979 goto write;
1980
1981 if (fstat(fileno(file), &st) < 0)
1982 goto close_write;
1983
1984 if (st.st_size != b->pos)
1985 goto close_write;
1986
1987 tmp = NOFAIL(malloc(b->pos));
1988 if (fread(tmp, 1, b->pos, file) != b->pos)
1989 goto free_write;
1990
1991 if (memcmp(tmp, b->p, b->pos) != 0)
1992 goto free_write;
1993
1994 free(tmp);
1995 fclose(file);
1996 return;
1997
1998 free_write:
1999 free(tmp);
2000 close_write:
2001 fclose(file);
2002 write:
2003 file = fopen(fname, "w");
2004 if (!file) {
2005 perror(fname);
2006 exit(1);
2007 }
2008 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
2009 perror(fname);
2010 exit(1);
2011 }
2012 fclose(file);
2013}
2014
2015/* parse Module.symvers file. line format:
2016 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
2017 **/
2018static void read_dump(const char *fname, unsigned int kernel)
2019{
2020 unsigned long size, pos = 0;
2021 void *file = grab_file(fname, &size);
2022 char *line;
2023
2024 if (!file)
2025 /* No symbol versions, silently ignore */
2026 return;
2027
2028 while ((line = get_next_line(&pos, file, size))) {
2029 char *symname, *modname, *d, *export, *end;
2030 unsigned int crc;
2031 struct module *mod;
2032 struct symbol *s;
2033
2034 if (!(symname = strchr(line, '\t')))
2035 goto fail;
2036 *symname++ = '\0';
2037 if (!(modname = strchr(symname, '\t')))
2038 goto fail;
2039 *modname++ = '\0';
2040 if ((export = strchr(modname, '\t')) != NULL)
2041 *export++ = '\0';
2042 if (export && ((end = strchr(export, '\t')) != NULL))
2043 *end = '\0';
2044 crc = strtoul(line, &d, 16);
2045 if (*symname == '\0' || *modname == '\0' || *d != '\0')
2046 goto fail;
2047 mod = find_module(modname);
2048 if (!mod) {
2049 if (is_vmlinux(modname))
2050 have_vmlinux = 1;
2051 mod = new_module(modname);
2052 mod->skip = 1;
2053 }
2054 s = sym_add_exported(symname, mod, export_no(export));
2055 s->kernel = kernel;
2056 s->preloaded = 1;
2057 sym_update_crc(symname, mod, crc, export_no(export));
2058 }
2059 return;
2060fail:
2061 fatal("parse error in symbol dump file\n");
2062}
2063
2064/* For normal builds always dump all symbols.
2065 * For external modules only dump symbols
2066 * that are not read from kernel Module.symvers.
2067 **/
2068static int dump_sym(struct symbol *sym)
2069{
2070 if (!external_module)
2071 return 1;
2072 if (sym->vmlinux || sym->kernel)
2073 return 0;
2074 return 1;
2075}
2076
2077static void write_dump(const char *fname)
2078{
2079 struct buffer buf = { };
2080 struct symbol *symbol;
2081 int n;
2082
2083 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
2084 symbol = symbolhash[n];
2085 while (symbol) {
2086 if (dump_sym(symbol))
2087 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
2088 symbol->crc, symbol->name,
2089 symbol->module->name,
2090 export_str(symbol->export));
2091 symbol = symbol->next;
2092 }
2093 }
2094 write_if_changed(&buf, fname);
2095}
2096
2097struct ext_sym_list {
2098 struct ext_sym_list *next;
2099 const char *file;
2100};
2101
2102int main(int argc, char **argv)
2103{
2104 struct module *mod;
2105 struct buffer buf = { };
2106 char *kernel_read = NULL, *module_read = NULL;
2107 char *dump_write = NULL;
2108 int opt;
2109 int err;
2110 struct ext_sym_list *extsym_iter;
2111 struct ext_sym_list *extsym_start = NULL;
2112
2113 while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) {
2114 switch (opt) {
2115 case 'i':
2116 kernel_read = optarg;
2117 break;
2118 case 'I':
2119 module_read = optarg;
2120 external_module = 1;
2121 break;
2122 case 'c':
2123 cross_build = 1;
2124 break;
2125 case 'e':
2126 external_module = 1;
2127 extsym_iter =
2128 NOFAIL(malloc(sizeof(*extsym_iter)));
2129 extsym_iter->next = extsym_start;
2130 extsym_iter->file = optarg;
2131 extsym_start = extsym_iter;
2132 break;
2133 case 'm':
2134 modversions = 1;
2135 break;
2136 case 'o':
2137 dump_write = optarg;
2138 break;
2139 case 'a':
2140 all_versions = 1;
2141 break;
2142 case 's':
2143 vmlinux_section_warnings = 0;
2144 break;
2145 case 'S':
2146 sec_mismatch_verbose = 0;
2147 break;
2148 case 'w':
2149 warn_unresolved = 1;
2150 break;
2151 default:
2152 exit(1);
2153 }
2154 }
2155
2156 if (kernel_read)
2157 read_dump(kernel_read, 1);
2158 if (module_read)
2159 read_dump(module_read, 0);
2160 while (extsym_start) {
2161 read_dump(extsym_start->file, 0);
2162 extsym_iter = extsym_start->next;
2163 free(extsym_start);
2164 extsym_start = extsym_iter;
2165 }
2166
2167 while (optind < argc)
2168 read_symbols(argv[optind++]);
2169
2170 for (mod = modules; mod; mod = mod->next) {
2171 if (mod->skip)
2172 continue;
2173 check_exports(mod);
2174 }
2175
2176 err = 0;
2177
2178 for (mod = modules; mod; mod = mod->next) {
2179 char fname[strlen(mod->name) + 10];
2180
2181 if (mod->skip)
2182 continue;
2183
2184 buf.pos = 0;
2185
2186 add_header(&buf, mod);
2187 add_intree_flag(&buf, !external_module);
2188 add_staging_flag(&buf, mod->name);
2189 err |= add_versions(&buf, mod);
2190 add_depends(&buf, mod, modules);
2191 add_moddevtable(&buf, mod);
2192 add_srcversion(&buf, mod);
2193
2194 sprintf(fname, "%s.mod.c", mod->name);
2195 write_if_changed(&buf, fname);
2196 }
2197
2198 if (dump_write)
2199 write_dump(dump_write);
2200 if (sec_mismatch_count && !sec_mismatch_verbose)
2201 warn("modpost: Found %d section mismatch(es).\n"
2202 "To see full details build your kernel with:\n"
2203 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
2204 sec_mismatch_count);
2205
2206 return err;
2207}