projects/linux·blob v3.19 · refs

2243 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 <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? */
27static int modversions = 0;
28/* Warn about undefined symbols? (do so if we have vmlinux) */
29static int 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 const 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 Module.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/* The pattern is an array of simple patterns.
776 * "foo" will match an exact string equal to "foo"
777 * "*foo" will match a string that ends with "foo"
778 * "foo*" will match a string that begins with "foo"
779 */
780static int match(const char *sym, const char * const pat[])
781{
782 const char *p;
783 while (*pat) {
784 p = *pat++;
785 const char *endp = p + strlen(p) - 1;
786
787 /* "*foo" */
788 if (*p == '*') {
789 if (strrcmp(sym, p + 1) == 0)
790 return 1;
791 }
792 /* "foo*" */
793 else if (*endp == '*') {
794 if (strncmp(sym, p, strlen(p) - 1) == 0)
795 return 1;
796 }
797 /* no wildcards */
798 else {
799 if (strcmp(p, sym) == 0)
800 return 1;
801 }
802 }
803 /* no match */
804 return 0;
805}
806
807/* sections that we do not want to do full section mismatch check on */
808static const char *const section_white_list[] =
809{
810 ".comment*",
811 ".debug*",
812 ".cranges", /* sh64 */
813 ".zdebug*", /* Compressed debug sections. */
814 ".GCC-command-line", /* mn10300 */
815 ".GCC.command.line", /* record-gcc-switches, non mn10300 */
816 ".mdebug*", /* alpha, score, mips etc. */
817 ".pdr", /* alpha, score, mips etc. */
818 ".stab*",
819 ".note*",
820 ".got*",
821 ".toc*",
822 ".xt.prop", /* xtensa */
823 ".xt.lit", /* xtensa */
824 ".arcextmap*", /* arc */
825 ".gnu.linkonce.arcext*", /* arc : modules */
826 ".gnu.lto*",
827 NULL
828};
829
830/*
831 * This is used to find sections missing the SHF_ALLOC flag.
832 * The cause of this is often a section specified in assembler
833 * without "ax" / "aw".
834 */
835static void check_section(const char *modname, struct elf_info *elf,
836 Elf_Shdr *sechdr)
837{
838 const char *sec = sech_name(elf, sechdr);
839
840 if (sechdr->sh_type == SHT_PROGBITS &&
841 !(sechdr->sh_flags & SHF_ALLOC) &&
842 !match(sec, section_white_list)) {
843 warn("%s (%s): unexpected non-allocatable section.\n"
844 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
845 "Note that for example <linux/init.h> contains\n"
846 "section definitions for use in .S files.\n\n",
847 modname, sec);
848 }
849}
850
851
852
853#define ALL_INIT_DATA_SECTIONS \
854 ".init.setup", ".init.rodata", ".meminit.rodata", \
855 ".init.data", ".meminit.data"
856#define ALL_EXIT_DATA_SECTIONS \
857 ".exit.data", ".memexit.data"
858
859#define ALL_INIT_TEXT_SECTIONS \
860 ".init.text", ".meminit.text"
861#define ALL_EXIT_TEXT_SECTIONS \
862 ".exit.text", ".memexit.text"
863
864#define ALL_PCI_INIT_SECTIONS \
865 ".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \
866 ".pci_fixup_enable", ".pci_fixup_resume", \
867 ".pci_fixup_resume_early", ".pci_fixup_suspend"
868
869#define ALL_XXXINIT_SECTIONS MEM_INIT_SECTIONS
870#define ALL_XXXEXIT_SECTIONS MEM_EXIT_SECTIONS
871
872#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
873#define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
874
875#define DATA_SECTIONS ".data", ".data.rel"
876#define TEXT_SECTIONS ".text", ".text.unlikely"
877
878#define INIT_SECTIONS ".init.*"
879#define MEM_INIT_SECTIONS ".meminit.*"
880
881#define EXIT_SECTIONS ".exit.*"
882#define MEM_EXIT_SECTIONS ".memexit.*"
883
884/* init data sections */
885static const char *const init_data_sections[] =
886 { ALL_INIT_DATA_SECTIONS, NULL };
887
888/* all init sections */
889static const char *const init_sections[] = { ALL_INIT_SECTIONS, NULL };
890
891/* All init and exit sections (code + data) */
892static const char *const init_exit_sections[] =
893 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
894
895/* data section */
896static const char *const data_sections[] = { DATA_SECTIONS, NULL };
897
898
899/* symbols in .data that may refer to init/exit sections */
900#define DEFAULT_SYMBOL_WHITE_LIST \
901 "*driver", \
902 "*_template", /* scsi uses *_template a lot */ \
903 "*_timer", /* arm uses ops structures named _timer a lot */ \
904 "*_sht", /* scsi also used *_sht to some extent */ \
905 "*_ops", \
906 "*_probe", \
907 "*_probe_one", \
908 "*_console"
909
910static const char *const head_sections[] = { ".head.text*", NULL };
911static const char *const linker_symbols[] =
912 { "__init_begin", "_sinittext", "_einittext", NULL };
913
914enum mismatch {
915 TEXT_TO_ANY_INIT,
916 DATA_TO_ANY_INIT,
917 TEXT_TO_ANY_EXIT,
918 DATA_TO_ANY_EXIT,
919 XXXINIT_TO_SOME_INIT,
920 XXXEXIT_TO_SOME_EXIT,
921 ANY_INIT_TO_ANY_EXIT,
922 ANY_EXIT_TO_ANY_INIT,
923 EXPORT_TO_INIT_EXIT,
924};
925
926struct sectioncheck {
927 const char *fromsec[20];
928 const char *tosec[20];
929 enum mismatch mismatch;
930 const char *symbol_white_list[20];
931};
932
933static const struct sectioncheck sectioncheck[] = {
934/* Do not reference init/exit code/data from
935 * normal code and data
936 */
937{
938 .fromsec = { TEXT_SECTIONS, NULL },
939 .tosec = { ALL_INIT_SECTIONS, NULL },
940 .mismatch = TEXT_TO_ANY_INIT,
941 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
942},
943{
944 .fromsec = { DATA_SECTIONS, NULL },
945 .tosec = { ALL_XXXINIT_SECTIONS, NULL },
946 .mismatch = DATA_TO_ANY_INIT,
947 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
948},
949{
950 .fromsec = { DATA_SECTIONS, NULL },
951 .tosec = { INIT_SECTIONS, NULL },
952 .mismatch = DATA_TO_ANY_INIT,
953 .symbol_white_list = {
954 "*_template", "*_timer", "*_sht", "*_ops",
955 "*_probe", "*_probe_one", "*_console", NULL
956 },
957},
958{
959 .fromsec = { TEXT_SECTIONS, NULL },
960 .tosec = { ALL_EXIT_SECTIONS, NULL },
961 .mismatch = TEXT_TO_ANY_EXIT,
962 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
963},
964{
965 .fromsec = { DATA_SECTIONS, NULL },
966 .tosec = { ALL_EXIT_SECTIONS, NULL },
967 .mismatch = DATA_TO_ANY_EXIT,
968 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
969},
970/* Do not reference init code/data from meminit code/data */
971{
972 .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
973 .tosec = { INIT_SECTIONS, NULL },
974 .mismatch = XXXINIT_TO_SOME_INIT,
975 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
976},
977/* Do not reference exit code/data from memexit code/data */
978{
979 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
980 .tosec = { EXIT_SECTIONS, NULL },
981 .mismatch = XXXEXIT_TO_SOME_EXIT,
982 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
983},
984/* Do not use exit code/data from init code */
985{
986 .fromsec = { ALL_INIT_SECTIONS, NULL },
987 .tosec = { ALL_EXIT_SECTIONS, NULL },
988 .mismatch = ANY_INIT_TO_ANY_EXIT,
989 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
990},
991/* Do not use init code/data from exit code */
992{
993 .fromsec = { ALL_EXIT_SECTIONS, NULL },
994 .tosec = { ALL_INIT_SECTIONS, NULL },
995 .mismatch = ANY_EXIT_TO_ANY_INIT,
996 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
997},
998{
999 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
1000 .tosec = { INIT_SECTIONS, NULL },
1001 .mismatch = ANY_INIT_TO_ANY_EXIT,
1002 .symbol_white_list = { NULL },
1003},
1004/* Do not export init/exit functions or data */
1005{
1006 .fromsec = { "__ksymtab*", NULL },
1007 .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
1008 .mismatch = EXPORT_TO_INIT_EXIT,
1009 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1010}
1011};
1012
1013static const struct sectioncheck *section_mismatch(
1014 const char *fromsec, const char *tosec)
1015{
1016 int i;
1017 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
1018 const struct sectioncheck *check = &sectioncheck[0];
1019
1020 for (i = 0; i < elems; i++) {
1021 if (match(fromsec, check->fromsec) &&
1022 match(tosec, check->tosec))
1023 return check;
1024 check++;
1025 }
1026 return NULL;
1027}
1028
1029/**
1030 * Whitelist to allow certain references to pass with no warning.
1031 *
1032 * Pattern 1:
1033 * If a module parameter is declared __initdata and permissions=0
1034 * then this is legal despite the warning generated.
1035 * We cannot see value of permissions here, so just ignore
1036 * this pattern.
1037 * The pattern is identified by:
1038 * tosec = .init.data
1039 * fromsec = .data*
1040 * atsym =__param*
1041 *
1042 * Pattern 1a:
1043 * module_param_call() ops can refer to __init set function if permissions=0
1044 * The pattern is identified by:
1045 * tosec = .init.text
1046 * fromsec = .data*
1047 * atsym = __param_ops_*
1048 *
1049 * Pattern 2:
1050 * Many drivers utilise a *driver container with references to
1051 * add, remove, probe functions etc.
1052 * the pattern is identified by:
1053 * tosec = init or exit section
1054 * fromsec = data section
1055 * atsym = *driver, *_template, *_sht, *_ops, *_probe,
1056 * *probe_one, *_console, *_timer
1057 *
1058 * Pattern 3:
1059 * Whitelist all references from .head.text to any init section
1060 *
1061 * Pattern 4:
1062 * Some symbols belong to init section but still it is ok to reference
1063 * these from non-init sections as these symbols don't have any memory
1064 * allocated for them and symbol address and value are same. So even
1065 * if init section is freed, its ok to reference those symbols.
1066 * For ex. symbols marking the init section boundaries.
1067 * This pattern is identified by
1068 * refsymname = __init_begin, _sinittext, _einittext
1069 *
1070 **/
1071static int secref_whitelist(const struct sectioncheck *mismatch,
1072 const char *fromsec, const char *fromsym,
1073 const char *tosec, const char *tosym)
1074{
1075 /* Check for pattern 1 */
1076 if (match(tosec, init_data_sections) &&
1077 match(fromsec, data_sections) &&
1078 (strncmp(fromsym, "__param", strlen("__param")) == 0))
1079 return 0;
1080
1081 /* Check for pattern 1a */
1082 if (strcmp(tosec, ".init.text") == 0 &&
1083 match(fromsec, data_sections) &&
1084 (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0))
1085 return 0;
1086
1087 /* Check for pattern 2 */
1088 if (match(tosec, init_exit_sections) &&
1089 match(fromsec, data_sections) &&
1090 match(fromsym, mismatch->symbol_white_list))
1091 return 0;
1092
1093 /* Check for pattern 3 */
1094 if (match(fromsec, head_sections) &&
1095 match(tosec, init_sections))
1096 return 0;
1097
1098 /* Check for pattern 4 */
1099 if (match(tosym, linker_symbols))
1100 return 0;
1101
1102 return 1;
1103}
1104
1105/**
1106 * Find symbol based on relocation record info.
1107 * In some cases the symbol supplied is a valid symbol so
1108 * return refsym. If st_name != 0 we assume this is a valid symbol.
1109 * In other cases the symbol needs to be looked up in the symbol table
1110 * based on section and address.
1111 * **/
1112static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
1113 Elf_Sym *relsym)
1114{
1115 Elf_Sym *sym;
1116 Elf_Sym *near = NULL;
1117 Elf64_Sword distance = 20;
1118 Elf64_Sword d;
1119 unsigned int relsym_secindex;
1120
1121 if (relsym->st_name != 0)
1122 return relsym;
1123
1124 relsym_secindex = get_secindex(elf, relsym);
1125 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1126 if (get_secindex(elf, sym) != relsym_secindex)
1127 continue;
1128 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
1129 continue;
1130 if (sym->st_value == addr)
1131 return sym;
1132 /* Find a symbol nearby - addr are maybe negative */
1133 d = sym->st_value - addr;
1134 if (d < 0)
1135 d = addr - sym->st_value;
1136 if (d < distance) {
1137 distance = d;
1138 near = sym;
1139 }
1140 }
1141 /* We need a close match */
1142 if (distance < 20)
1143 return near;
1144 else
1145 return NULL;
1146}
1147
1148static inline int is_arm_mapping_symbol(const char *str)
1149{
1150 return str[0] == '$' && strchr("axtd", str[1])
1151 && (str[2] == '\0' || str[2] == '.');
1152}
1153
1154/*
1155 * If there's no name there, ignore it; likewise, ignore it if it's
1156 * one of the magic symbols emitted used by current ARM tools.
1157 *
1158 * Otherwise if find_symbols_between() returns those symbols, they'll
1159 * fail the whitelist tests and cause lots of false alarms ... fixable
1160 * only by merging __exit and __init sections into __text, bloating
1161 * the kernel (which is especially evil on embedded platforms).
1162 */
1163static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
1164{
1165 const char *name = elf->strtab + sym->st_name;
1166
1167 if (!name || !strlen(name))
1168 return 0;
1169 return !is_arm_mapping_symbol(name);
1170}
1171
1172/*
1173 * Find symbols before or equal addr and after addr - in the section sec.
1174 * If we find two symbols with equal offset prefer one with a valid name.
1175 * The ELF format may have a better way to detect what type of symbol
1176 * it is, but this works for now.
1177 **/
1178static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
1179 const char *sec)
1180{
1181 Elf_Sym *sym;
1182 Elf_Sym *near = NULL;
1183 Elf_Addr distance = ~0;
1184
1185 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1186 const char *symsec;
1187
1188 if (is_shndx_special(sym->st_shndx))
1189 continue;
1190 symsec = sec_name(elf, get_secindex(elf, sym));
1191 if (strcmp(symsec, sec) != 0)
1192 continue;
1193 if (!is_valid_name(elf, sym))
1194 continue;
1195 if (sym->st_value <= addr) {
1196 if ((addr - sym->st_value) < distance) {
1197 distance = addr - sym->st_value;
1198 near = sym;
1199 } else if ((addr - sym->st_value) == distance) {
1200 near = sym;
1201 }
1202 }
1203 }
1204 return near;
1205}
1206
1207/*
1208 * Convert a section name to the function/data attribute
1209 * .init.text => __init
1210 * .memexitconst => __memconst
1211 * etc.
1212 *
1213 * The memory of returned value has been allocated on a heap. The user of this
1214 * method should free it after usage.
1215*/
1216static char *sec2annotation(const char *s)
1217{
1218 if (match(s, init_exit_sections)) {
1219 char *p = malloc(20);
1220 char *r = p;
1221
1222 *p++ = '_';
1223 *p++ = '_';
1224 if (*s == '.')
1225 s++;
1226 while (*s && *s != '.')
1227 *p++ = *s++;
1228 *p = '\0';
1229 if (*s == '.')
1230 s++;
1231 if (strstr(s, "rodata") != NULL)
1232 strcat(p, "const ");
1233 else if (strstr(s, "data") != NULL)
1234 strcat(p, "data ");
1235 else
1236 strcat(p, " ");
1237 return r;
1238 } else {
1239 return strdup("");
1240 }
1241}
1242
1243static int is_function(Elf_Sym *sym)
1244{
1245 if (sym)
1246 return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
1247 else
1248 return -1;
1249}
1250
1251static void print_section_list(const char * const list[20])
1252{
1253 const char *const *s = list;
1254
1255 while (*s) {
1256 fprintf(stderr, "%s", *s);
1257 s++;
1258 if (*s)
1259 fprintf(stderr, ", ");
1260 }
1261 fprintf(stderr, "\n");
1262}
1263
1264/*
1265 * Print a warning about a section mismatch.
1266 * Try to find symbols near it so user can find it.
1267 * Check whitelist before warning - it may be a false positive.
1268 */
1269static void report_sec_mismatch(const char *modname,
1270 const struct sectioncheck *mismatch,
1271 const char *fromsec,
1272 unsigned long long fromaddr,
1273 const char *fromsym,
1274 int from_is_func,
1275 const char *tosec, const char *tosym,
1276 int to_is_func)
1277{
1278 const char *from, *from_p;
1279 const char *to, *to_p;
1280 char *prl_from;
1281 char *prl_to;
1282
1283 switch (from_is_func) {
1284 case 0: from = "variable"; from_p = ""; break;
1285 case 1: from = "function"; from_p = "()"; break;
1286 default: from = "(unknown reference)"; from_p = ""; break;
1287 }
1288 switch (to_is_func) {
1289 case 0: to = "variable"; to_p = ""; break;
1290 case 1: to = "function"; to_p = "()"; break;
1291 default: to = "(unknown reference)"; to_p = ""; break;
1292 }
1293
1294 sec_mismatch_count++;
1295 if (!sec_mismatch_verbose)
1296 return;
1297
1298 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1299 "to the %s %s:%s%s\n",
1300 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
1301 tosym, to_p);
1302
1303 switch (mismatch->mismatch) {
1304 case TEXT_TO_ANY_INIT:
1305 prl_from = sec2annotation(fromsec);
1306 prl_to = sec2annotation(tosec);
1307 fprintf(stderr,
1308 "The function %s%s() references\n"
1309 "the %s %s%s%s.\n"
1310 "This is often because %s lacks a %s\n"
1311 "annotation or the annotation of %s is wrong.\n",
1312 prl_from, fromsym,
1313 to, prl_to, tosym, to_p,
1314 fromsym, prl_to, tosym);
1315 free(prl_from);
1316 free(prl_to);
1317 break;
1318 case DATA_TO_ANY_INIT: {
1319 prl_to = sec2annotation(tosec);
1320 fprintf(stderr,
1321 "The variable %s references\n"
1322 "the %s %s%s%s\n"
1323 "If the reference is valid then annotate the\n"
1324 "variable with __init* or __refdata (see linux/init.h) "
1325 "or name the variable:\n",
1326 fromsym, to, prl_to, tosym, to_p);
1327 print_section_list(mismatch->symbol_white_list);
1328 free(prl_to);
1329 break;
1330 }
1331 case TEXT_TO_ANY_EXIT:
1332 prl_to = sec2annotation(tosec);
1333 fprintf(stderr,
1334 "The function %s() references a %s in an exit section.\n"
1335 "Often the %s %s%s has valid usage outside the exit section\n"
1336 "and the fix is to remove the %sannotation of %s.\n",
1337 fromsym, to, to, tosym, to_p, prl_to, tosym);
1338 free(prl_to);
1339 break;
1340 case DATA_TO_ANY_EXIT: {
1341 prl_to = sec2annotation(tosec);
1342 fprintf(stderr,
1343 "The variable %s references\n"
1344 "the %s %s%s%s\n"
1345 "If the reference is valid then annotate the\n"
1346 "variable with __exit* (see linux/init.h) or "
1347 "name the variable:\n",
1348 fromsym, to, prl_to, tosym, to_p);
1349 print_section_list(mismatch->symbol_white_list);
1350 free(prl_to);
1351 break;
1352 }
1353 case XXXINIT_TO_SOME_INIT:
1354 case XXXEXIT_TO_SOME_EXIT:
1355 prl_from = sec2annotation(fromsec);
1356 prl_to = sec2annotation(tosec);
1357 fprintf(stderr,
1358 "The %s %s%s%s references\n"
1359 "a %s %s%s%s.\n"
1360 "If %s is only used by %s then\n"
1361 "annotate %s with a matching annotation.\n",
1362 from, prl_from, fromsym, from_p,
1363 to, prl_to, tosym, to_p,
1364 tosym, fromsym, tosym);
1365 free(prl_from);
1366 free(prl_to);
1367 break;
1368 case ANY_INIT_TO_ANY_EXIT:
1369 prl_from = sec2annotation(fromsec);
1370 prl_to = sec2annotation(tosec);
1371 fprintf(stderr,
1372 "The %s %s%s%s references\n"
1373 "a %s %s%s%s.\n"
1374 "This is often seen when error handling "
1375 "in the init function\n"
1376 "uses functionality in the exit path.\n"
1377 "The fix is often to remove the %sannotation of\n"
1378 "%s%s so it may be used outside an exit section.\n",
1379 from, prl_from, fromsym, from_p,
1380 to, prl_to, tosym, to_p,
1381 prl_to, tosym, to_p);
1382 free(prl_from);
1383 free(prl_to);
1384 break;
1385 case ANY_EXIT_TO_ANY_INIT:
1386 prl_from = sec2annotation(fromsec);
1387 prl_to = sec2annotation(tosec);
1388 fprintf(stderr,
1389 "The %s %s%s%s references\n"
1390 "a %s %s%s%s.\n"
1391 "This is often seen when error handling "
1392 "in the exit function\n"
1393 "uses functionality in the init path.\n"
1394 "The fix is often to remove the %sannotation of\n"
1395 "%s%s so it may be used outside an init section.\n",
1396 from, prl_from, fromsym, from_p,
1397 to, prl_to, tosym, to_p,
1398 prl_to, tosym, to_p);
1399 free(prl_from);
1400 free(prl_to);
1401 break;
1402 case EXPORT_TO_INIT_EXIT:
1403 prl_to = sec2annotation(tosec);
1404 fprintf(stderr,
1405 "The symbol %s is exported and annotated %s\n"
1406 "Fix this by removing the %sannotation of %s "
1407 "or drop the export.\n",
1408 tosym, prl_to, prl_to, tosym);
1409 free(prl_to);
1410 break;
1411 }
1412 fprintf(stderr, "\n");
1413}
1414
1415static void check_section_mismatch(const char *modname, struct elf_info *elf,
1416 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1417{
1418 const char *tosec;
1419 const struct sectioncheck *mismatch;
1420
1421 tosec = sec_name(elf, get_secindex(elf, sym));
1422 mismatch = section_mismatch(fromsec, tosec);
1423 if (mismatch) {
1424 Elf_Sym *to;
1425 Elf_Sym *from;
1426 const char *tosym;
1427 const char *fromsym;
1428
1429 from = find_elf_symbol2(elf, r->r_offset, fromsec);
1430 fromsym = sym_name(elf, from);
1431 to = find_elf_symbol(elf, r->r_addend, sym);
1432 tosym = sym_name(elf, to);
1433
1434 if (!strncmp(fromsym, "reference___initcall",
1435 sizeof("reference___initcall")-1))
1436 return;
1437
1438 /* check whitelist - we may ignore it */
1439 if (secref_whitelist(mismatch,
1440 fromsec, fromsym, tosec, tosym)) {
1441 report_sec_mismatch(modname, mismatch,
1442 fromsec, r->r_offset, fromsym,
1443 is_function(from), tosec, tosym,
1444 is_function(to));
1445 }
1446 }
1447}
1448
1449static unsigned int *reloc_location(struct elf_info *elf,
1450 Elf_Shdr *sechdr, Elf_Rela *r)
1451{
1452 Elf_Shdr *sechdrs = elf->sechdrs;
1453 int section = sechdr->sh_info;
1454
1455 return (void *)elf->hdr + sechdrs[section].sh_offset +
1456 r->r_offset;
1457}
1458
1459static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1460{
1461 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1462 unsigned int *location = reloc_location(elf, sechdr, r);
1463
1464 switch (r_typ) {
1465 case R_386_32:
1466 r->r_addend = TO_NATIVE(*location);
1467 break;
1468 case R_386_PC32:
1469 r->r_addend = TO_NATIVE(*location) + 4;
1470 /* For CONFIG_RELOCATABLE=y */
1471 if (elf->hdr->e_type == ET_EXEC)
1472 r->r_addend += r->r_offset;
1473 break;
1474 }
1475 return 0;
1476}
1477
1478#ifndef R_ARM_CALL
1479#define R_ARM_CALL 28
1480#endif
1481#ifndef R_ARM_JUMP24
1482#define R_ARM_JUMP24 29
1483#endif
1484
1485#ifndef R_ARM_THM_CALL
1486#define R_ARM_THM_CALL 10
1487#endif
1488#ifndef R_ARM_THM_JUMP24
1489#define R_ARM_THM_JUMP24 30
1490#endif
1491#ifndef R_ARM_THM_JUMP19
1492#define R_ARM_THM_JUMP19 51
1493#endif
1494
1495static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1496{
1497 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1498
1499 switch (r_typ) {
1500 case R_ARM_ABS32:
1501 /* From ARM ABI: (S + A) | T */
1502 r->r_addend = (int)(long)
1503 (elf->symtab_start + ELF_R_SYM(r->r_info));
1504 break;
1505 case R_ARM_PC24:
1506 case R_ARM_CALL:
1507 case R_ARM_JUMP24:
1508 case R_ARM_THM_CALL:
1509 case R_ARM_THM_JUMP24:
1510 case R_ARM_THM_JUMP19:
1511 /* From ARM ABI: ((S + A) | T) - P */
1512 r->r_addend = (int)(long)(elf->hdr +
1513 sechdr->sh_offset +
1514 (r->r_offset - sechdr->sh_addr));
1515 break;
1516 default:
1517 return 1;
1518 }
1519 return 0;
1520}
1521
1522static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1523{
1524 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1525 unsigned int *location = reloc_location(elf, sechdr, r);
1526 unsigned int inst;
1527
1528 if (r_typ == R_MIPS_HI16)
1529 return 1; /* skip this */
1530 inst = TO_NATIVE(*location);
1531 switch (r_typ) {
1532 case R_MIPS_LO16:
1533 r->r_addend = inst & 0xffff;
1534 break;
1535 case R_MIPS_26:
1536 r->r_addend = (inst & 0x03ffffff) << 2;
1537 break;
1538 case R_MIPS_32:
1539 r->r_addend = inst;
1540 break;
1541 }
1542 return 0;
1543}
1544
1545static void section_rela(const char *modname, struct elf_info *elf,
1546 Elf_Shdr *sechdr)
1547{
1548 Elf_Sym *sym;
1549 Elf_Rela *rela;
1550 Elf_Rela r;
1551 unsigned int r_sym;
1552 const char *fromsec;
1553
1554 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
1555 Elf_Rela *stop = (void *)start + sechdr->sh_size;
1556
1557 fromsec = sech_name(elf, sechdr);
1558 fromsec += strlen(".rela");
1559 /* if from section (name) is know good then skip it */
1560 if (match(fromsec, section_white_list))
1561 return;
1562
1563 for (rela = start; rela < stop; rela++) {
1564 r.r_offset = TO_NATIVE(rela->r_offset);
1565#if KERNEL_ELFCLASS == ELFCLASS64
1566 if (elf->hdr->e_machine == EM_MIPS) {
1567 unsigned int r_typ;
1568 r_sym = ELF64_MIPS_R_SYM(rela->r_info);
1569 r_sym = TO_NATIVE(r_sym);
1570 r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
1571 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1572 } else {
1573 r.r_info = TO_NATIVE(rela->r_info);
1574 r_sym = ELF_R_SYM(r.r_info);
1575 }
1576#else
1577 r.r_info = TO_NATIVE(rela->r_info);
1578 r_sym = ELF_R_SYM(r.r_info);
1579#endif
1580 r.r_addend = TO_NATIVE(rela->r_addend);
1581 sym = elf->symtab_start + r_sym;
1582 /* Skip special sections */
1583 if (is_shndx_special(sym->st_shndx))
1584 continue;
1585 check_section_mismatch(modname, elf, &r, sym, fromsec);
1586 }
1587}
1588
1589static void section_rel(const char *modname, struct elf_info *elf,
1590 Elf_Shdr *sechdr)
1591{
1592 Elf_Sym *sym;
1593 Elf_Rel *rel;
1594 Elf_Rela r;
1595 unsigned int r_sym;
1596 const char *fromsec;
1597
1598 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
1599 Elf_Rel *stop = (void *)start + sechdr->sh_size;
1600
1601 fromsec = sech_name(elf, sechdr);
1602 fromsec += strlen(".rel");
1603 /* if from section (name) is know good then skip it */
1604 if (match(fromsec, section_white_list))
1605 return;
1606
1607 for (rel = start; rel < stop; rel++) {
1608 r.r_offset = TO_NATIVE(rel->r_offset);
1609#if KERNEL_ELFCLASS == ELFCLASS64
1610 if (elf->hdr->e_machine == EM_MIPS) {
1611 unsigned int r_typ;
1612 r_sym = ELF64_MIPS_R_SYM(rel->r_info);
1613 r_sym = TO_NATIVE(r_sym);
1614 r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
1615 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1616 } else {
1617 r.r_info = TO_NATIVE(rel->r_info);
1618 r_sym = ELF_R_SYM(r.r_info);
1619 }
1620#else
1621 r.r_info = TO_NATIVE(rel->r_info);
1622 r_sym = ELF_R_SYM(r.r_info);
1623#endif
1624 r.r_addend = 0;
1625 switch (elf->hdr->e_machine) {
1626 case EM_386:
1627 if (addend_386_rel(elf, sechdr, &r))
1628 continue;
1629 break;
1630 case EM_ARM:
1631 if (addend_arm_rel(elf, sechdr, &r))
1632 continue;
1633 break;
1634 case EM_MIPS:
1635 if (addend_mips_rel(elf, sechdr, &r))
1636 continue;
1637 break;
1638 }
1639 sym = elf->symtab_start + r_sym;
1640 /* Skip special sections */
1641 if (is_shndx_special(sym->st_shndx))
1642 continue;
1643 check_section_mismatch(modname, elf, &r, sym, fromsec);
1644 }
1645}
1646
1647/**
1648 * A module includes a number of sections that are discarded
1649 * either when loaded or when used as built-in.
1650 * For loaded modules all functions marked __init and all data
1651 * marked __initdata will be discarded when the module has been initialized.
1652 * Likewise for modules used built-in the sections marked __exit
1653 * are discarded because __exit marked function are supposed to be called
1654 * only when a module is unloaded which never happens for built-in modules.
1655 * The check_sec_ref() function traverses all relocation records
1656 * to find all references to a section that reference a section that will
1657 * be discarded and warns about it.
1658 **/
1659static void check_sec_ref(struct module *mod, const char *modname,
1660 struct elf_info *elf)
1661{
1662 int i;
1663 Elf_Shdr *sechdrs = elf->sechdrs;
1664
1665 /* Walk through all sections */
1666 for (i = 0; i < elf->num_sections; i++) {
1667 check_section(modname, elf, &elf->sechdrs[i]);
1668 /* We want to process only relocation sections and not .init */
1669 if (sechdrs[i].sh_type == SHT_RELA)
1670 section_rela(modname, elf, &elf->sechdrs[i]);
1671 else if (sechdrs[i].sh_type == SHT_REL)
1672 section_rel(modname, elf, &elf->sechdrs[i]);
1673 }
1674}
1675
1676static char *remove_dot(char *s)
1677{
1678 size_t n = strcspn(s, ".");
1679
1680 if (n && s[n]) {
1681 size_t m = strspn(s + n + 1, "0123456789");
1682 if (m && (s[n + m] == '.' || s[n + m] == 0))
1683 s[n] = 0;
1684 }
1685 return s;
1686}
1687
1688static void read_symbols(char *modname)
1689{
1690 const char *symname;
1691 char *version;
1692 char *license;
1693 struct module *mod;
1694 struct elf_info info = { };
1695 Elf_Sym *sym;
1696
1697 if (!parse_elf(&info, modname))
1698 return;
1699
1700 mod = new_module(modname);
1701
1702 /* When there's no vmlinux, don't print warnings about
1703 * unresolved symbols (since there'll be too many ;) */
1704 if (is_vmlinux(modname)) {
1705 have_vmlinux = 1;
1706 mod->skip = 1;
1707 }
1708
1709 license = get_modinfo(info.modinfo, info.modinfo_len, "license");
1710 if (info.modinfo && !license && !is_vmlinux(modname))
1711 warn("modpost: missing MODULE_LICENSE() in %s\n"
1712 "see include/linux/module.h for "
1713 "more information\n", modname);
1714 while (license) {
1715 if (license_is_gpl_compatible(license))
1716 mod->gpl_compatible = 1;
1717 else {
1718 mod->gpl_compatible = 0;
1719 break;
1720 }
1721 license = get_next_modinfo(info.modinfo, info.modinfo_len,
1722 "license", license);
1723 }
1724
1725 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
1726 symname = remove_dot(info.strtab + sym->st_name);
1727
1728 handle_modversions(mod, &info, sym, symname);
1729 handle_moddevtable(mod, &info, sym, symname);
1730 }
1731 if (!is_vmlinux(modname) ||
1732 (is_vmlinux(modname) && vmlinux_section_warnings))
1733 check_sec_ref(mod, modname, &info);
1734
1735 version = get_modinfo(info.modinfo, info.modinfo_len, "version");
1736 if (version)
1737 maybe_frob_rcs_version(modname, version, info.modinfo,
1738 version - (char *)info.hdr);
1739 if (version || (all_versions && !is_vmlinux(modname)))
1740 get_src_version(modname, mod->srcversion,
1741 sizeof(mod->srcversion)-1);
1742
1743 parse_elf_finish(&info);
1744
1745 /* Our trick to get versioning for module struct etc. - it's
1746 * never passed as an argument to an exported function, so
1747 * the automatic versioning doesn't pick it up, but it's really
1748 * important anyhow */
1749 if (modversions)
1750 mod->unres = alloc_symbol("module_layout", 0, mod->unres);
1751}
1752
1753static void read_symbols_from_files(const char *filename)
1754{
1755 FILE *in = stdin;
1756 char fname[PATH_MAX];
1757
1758 if (strcmp(filename, "-") != 0) {
1759 in = fopen(filename, "r");
1760 if (!in)
1761 fatal("Can't open filenames file %s: %m", filename);
1762 }
1763
1764 while (fgets(fname, PATH_MAX, in) != NULL) {
1765 if (strends(fname, "\n"))
1766 fname[strlen(fname)-1] = '\0';
1767 read_symbols(fname);
1768 }
1769
1770 if (in != stdin)
1771 fclose(in);
1772}
1773
1774#define SZ 500
1775
1776/* We first write the generated file into memory using the
1777 * following helper, then compare to the file on disk and
1778 * only update the later if anything changed */
1779
1780void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
1781 const char *fmt, ...)
1782{
1783 char tmp[SZ];
1784 int len;
1785 va_list ap;
1786
1787 va_start(ap, fmt);
1788 len = vsnprintf(tmp, SZ, fmt, ap);
1789 buf_write(buf, tmp, len);
1790 va_end(ap);
1791}
1792
1793void buf_write(struct buffer *buf, const char *s, int len)
1794{
1795 if (buf->size - buf->pos < len) {
1796 buf->size += len + SZ;
1797 buf->p = realloc(buf->p, buf->size);
1798 }
1799 strncpy(buf->p + buf->pos, s, len);
1800 buf->pos += len;
1801}
1802
1803static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
1804{
1805 const char *e = is_vmlinux(m) ?"":".ko";
1806
1807 switch (exp) {
1808 case export_gpl:
1809 fatal("modpost: GPL-incompatible module %s%s "
1810 "uses GPL-only symbol '%s'\n", m, e, s);
1811 break;
1812 case export_unused_gpl:
1813 fatal("modpost: GPL-incompatible module %s%s "
1814 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
1815 break;
1816 case export_gpl_future:
1817 warn("modpost: GPL-incompatible module %s%s "
1818 "uses future GPL-only symbol '%s'\n", m, e, s);
1819 break;
1820 case export_plain:
1821 case export_unused:
1822 case export_unknown:
1823 /* ignore */
1824 break;
1825 }
1826}
1827
1828static void check_for_unused(enum export exp, const char *m, const char *s)
1829{
1830 const char *e = is_vmlinux(m) ?"":".ko";
1831
1832 switch (exp) {
1833 case export_unused:
1834 case export_unused_gpl:
1835 warn("modpost: module %s%s "
1836 "uses symbol '%s' marked UNUSED\n", m, e, s);
1837 break;
1838 default:
1839 /* ignore */
1840 break;
1841 }
1842}
1843
1844static void check_exports(struct module *mod)
1845{
1846 struct symbol *s, *exp;
1847
1848 for (s = mod->unres; s; s = s->next) {
1849 const char *basename;
1850 exp = find_symbol(s->name);
1851 if (!exp || exp->module == mod)
1852 continue;
1853 basename = strrchr(mod->name, '/');
1854 if (basename)
1855 basename++;
1856 else
1857 basename = mod->name;
1858 if (!mod->gpl_compatible)
1859 check_for_gpl_usage(exp->export, basename, exp->name);
1860 check_for_unused(exp->export, basename, exp->name);
1861 }
1862}
1863
1864/**
1865 * Header for the generated file
1866 **/
1867static void add_header(struct buffer *b, struct module *mod)
1868{
1869 buf_printf(b, "#include <linux/module.h>\n");
1870 buf_printf(b, "#include <linux/vermagic.h>\n");
1871 buf_printf(b, "#include <linux/compiler.h>\n");
1872 buf_printf(b, "\n");
1873 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1874 buf_printf(b, "\n");
1875 buf_printf(b, "__visible struct module __this_module\n");
1876 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
1877 buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
1878 if (mod->has_init)
1879 buf_printf(b, "\t.init = init_module,\n");
1880 if (mod->has_cleanup)
1881 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
1882 "\t.exit = cleanup_module,\n"
1883 "#endif\n");
1884 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
1885 buf_printf(b, "};\n");
1886}
1887
1888static void add_intree_flag(struct buffer *b, int is_intree)
1889{
1890 if (is_intree)
1891 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
1892}
1893
1894static void add_staging_flag(struct buffer *b, const char *name)
1895{
1896 static const char *staging_dir = "drivers/staging";
1897
1898 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0)
1899 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
1900}
1901
1902/**
1903 * Record CRCs for unresolved symbols
1904 **/
1905static int add_versions(struct buffer *b, struct module *mod)
1906{
1907 struct symbol *s, *exp;
1908 int err = 0;
1909
1910 for (s = mod->unres; s; s = s->next) {
1911 exp = find_symbol(s->name);
1912 if (!exp || exp->module == mod) {
1913 if (have_vmlinux && !s->weak) {
1914 if (warn_unresolved) {
1915 warn("\"%s\" [%s.ko] undefined!\n",
1916 s->name, mod->name);
1917 } else {
1918 merror("\"%s\" [%s.ko] undefined!\n",
1919 s->name, mod->name);
1920 err = 1;
1921 }
1922 }
1923 continue;
1924 }
1925 s->module = exp->module;
1926 s->crc_valid = exp->crc_valid;
1927 s->crc = exp->crc;
1928 }
1929
1930 if (!modversions)
1931 return err;
1932
1933 buf_printf(b, "\n");
1934 buf_printf(b, "static const struct modversion_info ____versions[]\n");
1935 buf_printf(b, "__used\n");
1936 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n");
1937
1938 for (s = mod->unres; s; s = s->next) {
1939 if (!s->module)
1940 continue;
1941 if (!s->crc_valid) {
1942 warn("\"%s\" [%s.ko] has no CRC!\n",
1943 s->name, mod->name);
1944 continue;
1945 }
1946 buf_printf(b, "\t{ %#8x, __VMLINUX_SYMBOL_STR(%s) },\n",
1947 s->crc, s->name);
1948 }
1949
1950 buf_printf(b, "};\n");
1951
1952 return err;
1953}
1954
1955static void add_depends(struct buffer *b, struct module *mod,
1956 struct module *modules)
1957{
1958 struct symbol *s;
1959 struct module *m;
1960 int first = 1;
1961
1962 for (m = modules; m; m = m->next)
1963 m->seen = is_vmlinux(m->name);
1964
1965 buf_printf(b, "\n");
1966 buf_printf(b, "static const char __module_depends[]\n");
1967 buf_printf(b, "__used\n");
1968 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n");
1969 buf_printf(b, "\"depends=");
1970 for (s = mod->unres; s; s = s->next) {
1971 const char *p;
1972 if (!s->module)
1973 continue;
1974
1975 if (s->module->seen)
1976 continue;
1977
1978 s->module->seen = 1;
1979 p = strrchr(s->module->name, '/');
1980 if (p)
1981 p++;
1982 else
1983 p = s->module->name;
1984 buf_printf(b, "%s%s", first ? "" : ",", p);
1985 first = 0;
1986 }
1987 buf_printf(b, "\";\n");
1988}
1989
1990static void add_srcversion(struct buffer *b, struct module *mod)
1991{
1992 if (mod->srcversion[0]) {
1993 buf_printf(b, "\n");
1994 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
1995 mod->srcversion);
1996 }
1997}
1998
1999static void write_if_changed(struct buffer *b, const char *fname)
2000{
2001 char *tmp;
2002 FILE *file;
2003 struct stat st;
2004
2005 file = fopen(fname, "r");
2006 if (!file)
2007 goto write;
2008
2009 if (fstat(fileno(file), &st) < 0)
2010 goto close_write;
2011
2012 if (st.st_size != b->pos)
2013 goto close_write;
2014
2015 tmp = NOFAIL(malloc(b->pos));
2016 if (fread(tmp, 1, b->pos, file) != b->pos)
2017 goto free_write;
2018
2019 if (memcmp(tmp, b->p, b->pos) != 0)
2020 goto free_write;
2021
2022 free(tmp);
2023 fclose(file);
2024 return;
2025
2026 free_write:
2027 free(tmp);
2028 close_write:
2029 fclose(file);
2030 write:
2031 file = fopen(fname, "w");
2032 if (!file) {
2033 perror(fname);
2034 exit(1);
2035 }
2036 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
2037 perror(fname);
2038 exit(1);
2039 }
2040 fclose(file);
2041}
2042
2043/* parse Module.symvers file. line format:
2044 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
2045 **/
2046static void read_dump(const char *fname, unsigned int kernel)
2047{
2048 unsigned long size, pos = 0;
2049 void *file = grab_file(fname, &size);
2050 char *line;
2051
2052 if (!file)
2053 /* No symbol versions, silently ignore */
2054 return;
2055
2056 while ((line = get_next_line(&pos, file, size))) {
2057 char *symname, *modname, *d, *export, *end;
2058 unsigned int crc;
2059 struct module *mod;
2060 struct symbol *s;
2061
2062 if (!(symname = strchr(line, '\t')))
2063 goto fail;
2064 *symname++ = '\0';
2065 if (!(modname = strchr(symname, '\t')))
2066 goto fail;
2067 *modname++ = '\0';
2068 if ((export = strchr(modname, '\t')) != NULL)
2069 *export++ = '\0';
2070 if (export && ((end = strchr(export, '\t')) != NULL))
2071 *end = '\0';
2072 crc = strtoul(line, &d, 16);
2073 if (*symname == '\0' || *modname == '\0' || *d != '\0')
2074 goto fail;
2075 mod = find_module(modname);
2076 if (!mod) {
2077 if (is_vmlinux(modname))
2078 have_vmlinux = 1;
2079 mod = new_module(modname);
2080 mod->skip = 1;
2081 }
2082 s = sym_add_exported(symname, mod, export_no(export));
2083 s->kernel = kernel;
2084 s->preloaded = 1;
2085 sym_update_crc(symname, mod, crc, export_no(export));
2086 }
2087 release_file(file, size);
2088 return;
2089fail:
2090 release_file(file, size);
2091 fatal("parse error in symbol dump file\n");
2092}
2093
2094/* For normal builds always dump all symbols.
2095 * For external modules only dump symbols
2096 * that are not read from kernel Module.symvers.
2097 **/
2098static int dump_sym(struct symbol *sym)
2099{
2100 if (!external_module)
2101 return 1;
2102 if (sym->vmlinux || sym->kernel)
2103 return 0;
2104 return 1;
2105}
2106
2107static void write_dump(const char *fname)
2108{
2109 struct buffer buf = { };
2110 struct symbol *symbol;
2111 int n;
2112
2113 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
2114 symbol = symbolhash[n];
2115 while (symbol) {
2116 if (dump_sym(symbol))
2117 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
2118 symbol->crc, symbol->name,
2119 symbol->module->name,
2120 export_str(symbol->export));
2121 symbol = symbol->next;
2122 }
2123 }
2124 write_if_changed(&buf, fname);
2125}
2126
2127struct ext_sym_list {
2128 struct ext_sym_list *next;
2129 const char *file;
2130};
2131
2132int main(int argc, char **argv)
2133{
2134 struct module *mod;
2135 struct buffer buf = { };
2136 char *kernel_read = NULL, *module_read = NULL;
2137 char *dump_write = NULL, *files_source = NULL;
2138 int opt;
2139 int err;
2140 struct ext_sym_list *extsym_iter;
2141 struct ext_sym_list *extsym_start = NULL;
2142
2143 while ((opt = getopt(argc, argv, "i:I:e:mnsST:o:awM:K:")) != -1) {
2144 switch (opt) {
2145 case 'i':
2146 kernel_read = optarg;
2147 break;
2148 case 'I':
2149 module_read = optarg;
2150 external_module = 1;
2151 break;
2152 case 'e':
2153 external_module = 1;
2154 extsym_iter =
2155 NOFAIL(malloc(sizeof(*extsym_iter)));
2156 extsym_iter->next = extsym_start;
2157 extsym_iter->file = optarg;
2158 extsym_start = extsym_iter;
2159 break;
2160 case 'm':
2161 modversions = 1;
2162 break;
2163 case 'n':
2164 ignore_missing_files = 1;
2165 break;
2166 case 'o':
2167 dump_write = optarg;
2168 break;
2169 case 'a':
2170 all_versions = 1;
2171 break;
2172 case 's':
2173 vmlinux_section_warnings = 0;
2174 break;
2175 case 'S':
2176 sec_mismatch_verbose = 0;
2177 break;
2178 case 'T':
2179 files_source = optarg;
2180 break;
2181 case 'w':
2182 warn_unresolved = 1;
2183 break;
2184 default:
2185 exit(1);
2186 }
2187 }
2188
2189 if (kernel_read)
2190 read_dump(kernel_read, 1);
2191 if (module_read)
2192 read_dump(module_read, 0);
2193 while (extsym_start) {
2194 read_dump(extsym_start->file, 0);
2195 extsym_iter = extsym_start->next;
2196 free(extsym_start);
2197 extsym_start = extsym_iter;
2198 }
2199
2200 while (optind < argc)
2201 read_symbols(argv[optind++]);
2202
2203 if (files_source)
2204 read_symbols_from_files(files_source);
2205
2206 for (mod = modules; mod; mod = mod->next) {
2207 if (mod->skip)
2208 continue;
2209 check_exports(mod);
2210 }
2211
2212 err = 0;
2213
2214 for (mod = modules; mod; mod = mod->next) {
2215 char fname[PATH_MAX];
2216
2217 if (mod->skip)
2218 continue;
2219
2220 buf.pos = 0;
2221
2222 add_header(&buf, mod);
2223 add_intree_flag(&buf, !external_module);
2224 add_staging_flag(&buf, mod->name);
2225 err |= add_versions(&buf, mod);
2226 add_depends(&buf, mod, modules);
2227 add_moddevtable(&buf, mod);
2228 add_srcversion(&buf, mod);
2229
2230 sprintf(fname, "%s.mod.c", mod->name);
2231 write_if_changed(&buf, fname);
2232 }
2233
2234 if (dump_write)
2235 write_dump(dump_write);
2236 if (sec_mismatch_count && !sec_mismatch_verbose)
2237 warn("modpost: Found %d section mismatch(es).\n"
2238 "To see full details build your kernel with:\n"
2239 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
2240 sec_mismatch_count);
2241
2242 return err;
2243}