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[linux-2.6/next.git] / scripts / mod / modpost.c
blob413c53693e62d818544c4c931ccf2c6ef48fbb8b
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? */
31 int modversions = 0;
32 /* Warn about undefined symbols? (do so if we have vmlinux) */
33 int have_vmlinux = 0;
34 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */
35 static int all_versions = 0;
36 /* If we are modposting external module set to 1 */
37 static int external_module = 0;
38 /* Warn about section mismatch in vmlinux if set to 1 */
39 static int vmlinux_section_warnings = 1;
40 /* Only warn about unresolved symbols */
41 static int warn_unresolved = 0;
42 /* How a symbol is exported */
43 static int sec_mismatch_count = 0;
44 static int sec_mismatch_verbose = 1;
45
46 enum 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
53 PRINTF 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
66 PRINTF 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
77 PRINTF 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
88 static 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
102 void *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 */
111 static struct module *modules;
112
113 static 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
123 static 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
152 struct 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
166 static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
167
168 /* This is based on the hash agorithm from gdbm, via tdb */
169 static 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 **/
185 static 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 */
198 static 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
211 static 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
226 static 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
239 static const char *export_str(enum export ex)
240 {
241 return export_list[ex].str;
242 }
243
244 static 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
257 static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
258 {
259 if (sec == elf->export_sec)
260 return export_plain;
261 else if (sec == elf->export_unused_sec)
262 return export_unused;
263 else if (sec == elf->export_gpl_sec)
264 return export_gpl;
265 else if (sec == elf->export_unused_gpl_sec)
266 return export_unused_gpl;
267 else if (sec == elf->export_gpl_future_sec)
268 return export_gpl_future;
269 else
270 return export_unknown;
271 }
272
273 /**
274 * Add an exported symbol - it may have already been added without a
275 * CRC, in this case just update the CRC
276 **/
277 static struct symbol *sym_add_exported(const char *name, struct module *mod,
278 enum export export)
279 {
280 struct symbol *s = find_symbol(name);
281
282 if (!s) {
283 s = new_symbol(name, mod, export);
284 } else {
285 if (!s->preloaded) {
286 warn("%s: '%s' exported twice. Previous export "
287 "was in %s%s\n", mod->name, name,
288 s->module->name,
289 is_vmlinux(s->module->name) ?"":".ko");
290 } else {
291 /* In case Modules.symvers was out of date */
292 s->module = mod;
293 }
294 }
295 s->preloaded = 0;
296 s->vmlinux = is_vmlinux(mod->name);
297 s->kernel = 0;
298 s->export = export;
299 return s;
300 }
301
302 static void sym_update_crc(const char *name, struct module *mod,
303 unsigned int crc, enum export export)
304 {
305 struct symbol *s = find_symbol(name);
306
307 if (!s)
308 s = new_symbol(name, mod, export);
309 s->crc = crc;
310 s->crc_valid = 1;
311 }
312
313 void *grab_file(const char *filename, unsigned long *size)
314 {
315 struct stat st;
316 void *map;
317 int fd;
318
319 fd = open(filename, O_RDONLY);
320 if (fd < 0 || fstat(fd, &st) != 0)
321 return NULL;
322
323 *size = st.st_size;
324 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
325 close(fd);
326
327 if (map == MAP_FAILED)
328 return NULL;
329 return map;
330 }
331
332 /**
333 * Return a copy of the next line in a mmap'ed file.
334 * spaces in the beginning of the line is trimmed away.
335 * Return a pointer to a static buffer.
336 **/
337 char *get_next_line(unsigned long *pos, void *file, unsigned long size)
338 {
339 static char line[4096];
340 int skip = 1;
341 size_t len = 0;
342 signed char *p = (signed char *)file + *pos;
343 char *s = line;
344
345 for (; *pos < size ; (*pos)++) {
346 if (skip && isspace(*p)) {
347 p++;
348 continue;
349 }
350 skip = 0;
351 if (*p != '\n' && (*pos < size)) {
352 len++;
353 *s++ = *p++;
354 if (len > 4095)
355 break; /* Too long, stop */
356 } else {
357 /* End of string */
358 *s = '\0';
359 return line;
360 }
361 }
362 /* End of buffer */
363 return NULL;
364 }
365
366 void release_file(void *file, unsigned long size)
367 {
368 munmap(file, size);
369 }
370
371 static int parse_elf(struct elf_info *info, const char *filename)
372 {
373 unsigned int i;
374 Elf_Ehdr *hdr;
375 Elf_Shdr *sechdrs;
376 Elf_Sym *sym;
377 const char *secstrings;
378 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
379
380 hdr = grab_file(filename, &info->size);
381 if (!hdr) {
382 perror(filename);
383 exit(1);
384 }
385 info->hdr = hdr;
386 if (info->size < sizeof(*hdr)) {
387 /* file too small, assume this is an empty .o file */
388 return 0;
389 }
390 /* Is this a valid ELF file? */
391 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
392 (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
393 (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
394 (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
395 /* Not an ELF file - silently ignore it */
396 return 0;
397 }
398 /* Fix endianness in ELF header */
399 hdr->e_type = TO_NATIVE(hdr->e_type);
400 hdr->e_machine = TO_NATIVE(hdr->e_machine);
401 hdr->e_version = TO_NATIVE(hdr->e_version);
402 hdr->e_entry = TO_NATIVE(hdr->e_entry);
403 hdr->e_phoff = TO_NATIVE(hdr->e_phoff);
404 hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
405 hdr->e_flags = TO_NATIVE(hdr->e_flags);
406 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize);
407 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
408 hdr->e_phnum = TO_NATIVE(hdr->e_phnum);
409 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
410 hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
411 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
412 sechdrs = (void *)hdr + hdr->e_shoff;
413 info->sechdrs = sechdrs;
414
415 /* Check if file offset is correct */
416 if (hdr->e_shoff > info->size) {
417 fatal("section header offset=%lu in file '%s' is bigger than "
418 "filesize=%lu\n", (unsigned long)hdr->e_shoff,
419 filename, info->size);
420 return 0;
421 }
422
423 if (hdr->e_shnum == SHN_UNDEF) {
424 /*
425 * There are more than 64k sections,
426 * read count from .sh_size.
427 */
428 info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
429 }
430 else {
431 info->num_sections = hdr->e_shnum;
432 }
433 if (hdr->e_shstrndx == SHN_XINDEX) {
434 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
435 }
436 else {
437 info->secindex_strings = hdr->e_shstrndx;
438 }
439
440 /* Fix endianness in section headers */
441 for (i = 0; i < info->num_sections; i++) {
442 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
443 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
444 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
445 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
446 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
447 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
448 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
449 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
450 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
451 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
452 }
453 /* Find symbol table. */
454 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
455 for (i = 1; i < info->num_sections; i++) {
456 const char *secname;
457 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
458
459 if (!nobits && sechdrs[i].sh_offset > info->size) {
460 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
461 "sizeof(*hrd)=%zu\n", filename,
462 (unsigned long)sechdrs[i].sh_offset,
463 sizeof(*hdr));
464 return 0;
465 }
466 secname = secstrings + sechdrs[i].sh_name;
467 if (strcmp(secname, ".modinfo") == 0) {
468 if (nobits)
469 fatal("%s has NOBITS .modinfo\n", filename);
470 info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
471 info->modinfo_len = sechdrs[i].sh_size;
472 } else if (strcmp(secname, "__ksymtab") == 0)
473 info->export_sec = i;
474 else if (strcmp(secname, "__ksymtab_unused") == 0)
475 info->export_unused_sec = i;
476 else if (strcmp(secname, "__ksymtab_gpl") == 0)
477 info->export_gpl_sec = i;
478 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
479 info->export_unused_gpl_sec = i;
480 else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
481 info->export_gpl_future_sec = i;
482
483 if (sechdrs[i].sh_type == SHT_SYMTAB) {
484 unsigned int sh_link_idx;
485 symtab_idx = i;
486 info->symtab_start = (void *)hdr +
487 sechdrs[i].sh_offset;
488 info->symtab_stop = (void *)hdr +
489 sechdrs[i].sh_offset + sechdrs[i].sh_size;
490 sh_link_idx = sechdrs[i].sh_link;
491 info->strtab = (void *)hdr +
492 sechdrs[sh_link_idx].sh_offset;
493 }
494
495 /* 32bit section no. table? ("more than 64k sections") */
496 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
497 symtab_shndx_idx = i;
498 info->symtab_shndx_start = (void *)hdr +
499 sechdrs[i].sh_offset;
500 info->symtab_shndx_stop = (void *)hdr +
501 sechdrs[i].sh_offset + sechdrs[i].sh_size;
502 }
503 }
504 if (!info->symtab_start)
505 fatal("%s has no symtab?\n", filename);
506
507 /* Fix endianness in symbols */
508 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
509 sym->st_shndx = TO_NATIVE(sym->st_shndx);
510 sym->st_name = TO_NATIVE(sym->st_name);
511 sym->st_value = TO_NATIVE(sym->st_value);
512 sym->st_size = TO_NATIVE(sym->st_size);
513 }
514
515 if (symtab_shndx_idx != ~0U) {
516 Elf32_Word *p;
517 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
518 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
519 filename, sechdrs[symtab_shndx_idx].sh_link,
520 symtab_idx);
521 /* Fix endianness */
522 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
523 p++)
524 *p = TO_NATIVE(*p);
525 }
526
527 return 1;
528 }
529
530 static void parse_elf_finish(struct elf_info *info)
531 {
532 release_file(info->hdr, info->size);
533 }
534
535 static int ignore_undef_symbol(struct elf_info *info, const char *symname)
536 {
537 /* ignore __this_module, it will be resolved shortly */
538 if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0)
539 return 1;
540 /* ignore global offset table */
541 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
542 return 1;
543 if (info->hdr->e_machine == EM_PPC)
544 /* Special register function linked on all modules during final link of .ko */
545 if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 ||
546 strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 ||
547 strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
548 strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0)
549 return 1;
550 if (info->hdr->e_machine == EM_PPC64)
551 /* Special register function linked on all modules during final link of .ko */
552 if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 ||
553 strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0)
554 return 1;
555 /* Do not ignore this symbol */
556 return 0;
557 }
558
559 #define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_"
560 #define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
561
562 static void handle_modversions(struct module *mod, struct elf_info *info,
563 Elf_Sym *sym, const char *symname)
564 {
565 unsigned int crc;
566 enum export export = export_from_sec(info, get_secindex(info, sym));
567
568 switch (sym->st_shndx) {
569 case SHN_COMMON:
570 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
571 break;
572 case SHN_ABS:
573 /* CRC'd symbol */
574 if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
575 crc = (unsigned int) sym->st_value;
576 sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
577 export);
578 }
579 break;
580 case SHN_UNDEF:
581 /* undefined symbol */
582 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
583 ELF_ST_BIND(sym->st_info) != STB_WEAK)
584 break;
585 if (ignore_undef_symbol(info, symname))
586 break;
587 /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
588 #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
589 /* add compatibility with older glibc */
590 #ifndef STT_SPARC_REGISTER
591 #define STT_SPARC_REGISTER STT_REGISTER
592 #endif
593 if (info->hdr->e_machine == EM_SPARC ||
594 info->hdr->e_machine == EM_SPARCV9) {
595 /* Ignore register directives. */
596 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
597 break;
598 if (symname[0] == '.') {
599 char *munged = strdup(symname);
600 munged[0] = '_';
601 munged[1] = toupper(munged[1]);
602 symname = munged;
603 }
604 }
605 #endif
606
607 if (memcmp(symname, MODULE_SYMBOL_PREFIX,
608 strlen(MODULE_SYMBOL_PREFIX)) == 0) {
609 mod->unres =
610 alloc_symbol(symname +
611 strlen(MODULE_SYMBOL_PREFIX),
612 ELF_ST_BIND(sym->st_info) == STB_WEAK,
613 mod->unres);
614 }
615 break;
616 default:
617 /* All exported symbols */
618 if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
619 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
620 export);
621 }
622 if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
623 mod->has_init = 1;
624 if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0)
625 mod->has_cleanup = 1;
626 break;
627 }
628 }
629
630 /**
631 * Parse tag=value strings from .modinfo section
632 **/
633 static char *next_string(char *string, unsigned long *secsize)
634 {
635 /* Skip non-zero chars */
636 while (string[0]) {
637 string++;
638 if ((*secsize)-- <= 1)
639 return NULL;
640 }
641
642 /* Skip any zero padding. */
643 while (!string[0]) {
644 string++;
645 if ((*secsize)-- <= 1)
646 return NULL;
647 }
648 return string;
649 }
650
651 static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
652 const char *tag, char *info)
653 {
654 char *p;
655 unsigned int taglen = strlen(tag);
656 unsigned long size = modinfo_len;
657
658 if (info) {
659 size -= info - (char *)modinfo;
660 modinfo = next_string(info, &size);
661 }
662
663 for (p = modinfo; p; p = next_string(p, &size)) {
664 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
665 return p + taglen + 1;
666 }
667 return NULL;
668 }
669
670 static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
671 const char *tag)
672
673 {
674 return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
675 }
676
677 /**
678 * Test if string s ends in string sub
679 * return 0 if match
680 **/
681 static int strrcmp(const char *s, const char *sub)
682 {
683 int slen, sublen;
684
685 if (!s || !sub)
686 return 1;
687
688 slen = strlen(s);
689 sublen = strlen(sub);
690
691 if ((slen == 0) || (sublen == 0))
692 return 1;
693
694 if (sublen > slen)
695 return 1;
696
697 return memcmp(s + slen - sublen, sub, sublen);
698 }
699
700 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
701 {
702 if (sym)
703 return elf->strtab + sym->st_name;
704 else
705 return "(unknown)";
706 }
707
708 static const char *sec_name(struct elf_info *elf, int secindex)
709 {
710 Elf_Shdr *sechdrs = elf->sechdrs;
711 return (void *)elf->hdr +
712 elf->sechdrs[elf->secindex_strings].sh_offset +
713 sechdrs[secindex].sh_name;
714 }
715
716 static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr)
717 {
718 return (void *)elf->hdr +
719 elf->sechdrs[elf->secindex_strings].sh_offset +
720 sechdr->sh_name;
721 }
722
723 /* if sym is empty or point to a string
724 * like ".[0-9]+" then return 1.
725 * This is the optional prefix added by ld to some sections
726 */
727 static int number_prefix(const char *sym)
728 {
729 if (*sym++ == '\0')
730 return 1;
731 if (*sym != '.')
732 return 0;
733 do {
734 char c = *sym++;
735 if (c < '0' || c > '9')
736 return 0;
737 } while (*sym);
738 return 1;
739 }
740
741 /* The pattern is an array of simple patterns.
742 * "foo" will match an exact string equal to "foo"
743 * "*foo" will match a string that ends with "foo"
744 * "foo*" will match a string that begins with "foo"
745 * "foo$" will match a string equal to "foo" or "foo.1"
746 * where the '1' can be any number including several digits.
747 * The $ syntax is for sections where ld append a dot number
748 * to make section name unique.
749 */
750 static int match(const char *sym, const char * const pat[])
751 {
752 const char *p;
753 while (*pat) {
754 p = *pat++;
755 const char *endp = p + strlen(p) - 1;
756
757 /* "*foo" */
758 if (*p == '*') {
759 if (strrcmp(sym, p + 1) == 0)
760 return 1;
761 }
762 /* "foo*" */
763 else if (*endp == '*') {
764 if (strncmp(sym, p, strlen(p) - 1) == 0)
765 return 1;
766 }
767 /* "foo$" */
768 else if (*endp == '$') {
769 if (strncmp(sym, p, strlen(p) - 1) == 0) {
770 if (number_prefix(sym + strlen(p) - 1))
771 return 1;
772 }
773 }
774 /* no wildcards */
775 else {
776 if (strcmp(p, sym) == 0)
777 return 1;
778 }
779 }
780 /* no match */
781 return 0;
782 }
783
784 /* sections that we do not want to do full section mismatch check on */
785 static const char *section_white_list[] =
786 {
787 ".comment*",
788 ".debug*",
789 ".zdebug*", /* Compressed debug sections. */
790 ".GCC-command-line", /* mn10300 */
791 ".mdebug*", /* alpha, score, mips etc. */
792 ".pdr", /* alpha, score, mips etc. */
793 ".stab*",
794 ".note*",
795 ".got*",
796 ".toc*",
797 NULL
798 };
799
800 /*
801 * This is used to find sections missing the SHF_ALLOC flag.
802 * The cause of this is often a section specified in assembler
803 * without "ax" / "aw".
804 */
805 static void check_section(const char *modname, struct elf_info *elf,
806 Elf_Shdr *sechdr)
807 {
808 const char *sec = sech_name(elf, sechdr);
809
810 if (sechdr->sh_type == SHT_PROGBITS &&
811 !(sechdr->sh_flags & SHF_ALLOC) &&
812 !match(sec, section_white_list)) {
813 warn("%s (%s): unexpected non-allocatable section.\n"
814 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
815 "Note that for example <linux/init.h> contains\n"
816 "section definitions for use in .S files.\n\n",
817 modname, sec);
818 }
819 }
820
821
822
823 #define ALL_INIT_DATA_SECTIONS \
824 ".init.setup$", ".init.rodata$", \
825 ".devinit.rodata$", ".cpuinit.rodata$", ".meminit.rodata$" \
826 ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$"
827 #define ALL_EXIT_DATA_SECTIONS \
828 ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$"
829
830 #define ALL_INIT_TEXT_SECTIONS \
831 ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$"
832 #define ALL_EXIT_TEXT_SECTIONS \
833 ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$"
834
835 #define ALL_XXXINIT_SECTIONS DEV_INIT_SECTIONS, CPU_INIT_SECTIONS, \
836 MEM_INIT_SECTIONS
837 #define ALL_XXXEXIT_SECTIONS DEV_EXIT_SECTIONS, CPU_EXIT_SECTIONS, \
838 MEM_EXIT_SECTIONS
839
840 #define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
841 #define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
842
843 #define DATA_SECTIONS ".data$", ".data.rel$"
844 #define TEXT_SECTIONS ".text$"
845
846 #define INIT_SECTIONS ".init.*"
847 #define DEV_INIT_SECTIONS ".devinit.*"
848 #define CPU_INIT_SECTIONS ".cpuinit.*"
849 #define MEM_INIT_SECTIONS ".meminit.*"
850
851 #define EXIT_SECTIONS ".exit.*"
852 #define DEV_EXIT_SECTIONS ".devexit.*"
853 #define CPU_EXIT_SECTIONS ".cpuexit.*"
854 #define MEM_EXIT_SECTIONS ".memexit.*"
855
856 /* init data sections */
857 static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL };
858
859 /* all init sections */
860 static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL };
861
862 /* All init and exit sections (code + data) */
863 static const char *init_exit_sections[] =
864 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
865
866 /* data section */
867 static const char *data_sections[] = { DATA_SECTIONS, NULL };
868
869
870 /* symbols in .data that may refer to init/exit sections */
871 #define DEFAULT_SYMBOL_WHITE_LIST \
872 "*driver", \
873 "*_template", /* scsi uses *_template a lot */ \
874 "*_timer", /* arm uses ops structures named _timer a lot */ \
875 "*_sht", /* scsi also used *_sht to some extent */ \
876 "*_ops", \
877 "*_probe", \
878 "*_probe_one", \
879 "*_console"
880
881 static const char *head_sections[] = { ".head.text*", NULL };
882 static const char *linker_symbols[] =
883 { "__init_begin", "_sinittext", "_einittext", NULL };
884
885 enum mismatch {
886 TEXT_TO_ANY_INIT,
887 DATA_TO_ANY_INIT,
888 TEXT_TO_ANY_EXIT,
889 DATA_TO_ANY_EXIT,
890 XXXINIT_TO_SOME_INIT,
891 XXXEXIT_TO_SOME_EXIT,
892 ANY_INIT_TO_ANY_EXIT,
893 ANY_EXIT_TO_ANY_INIT,
894 EXPORT_TO_INIT_EXIT,
895 };
896
897 struct sectioncheck {
898 const char *fromsec[20];
899 const char *tosec[20];
900 enum mismatch mismatch;
901 const char *symbol_white_list[20];
902 };
903
904 const struct sectioncheck sectioncheck[] = {
905 /* Do not reference init/exit code/data from
906 * normal code and data
907 */
908 {
909 .fromsec = { TEXT_SECTIONS, NULL },
910 .tosec = { ALL_INIT_SECTIONS, NULL },
911 .mismatch = TEXT_TO_ANY_INIT,
912 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
913 },
914 {
915 .fromsec = { DATA_SECTIONS, NULL },
916 .tosec = { ALL_XXXINIT_SECTIONS, NULL },
917 .mismatch = DATA_TO_ANY_INIT,
918 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
919 },
920 {
921 .fromsec = { DATA_SECTIONS, NULL },
922 .tosec = { INIT_SECTIONS, NULL },
923 .mismatch = DATA_TO_ANY_INIT,
924 .symbol_white_list = {
925 "*_template", "*_timer", "*_sht", "*_ops",
926 "*_probe", "*_probe_one", "*_console", NULL
927 },
928 },
929 {
930 .fromsec = { TEXT_SECTIONS, NULL },
931 .tosec = { ALL_EXIT_SECTIONS, NULL },
932 .mismatch = TEXT_TO_ANY_EXIT,
933 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
934 },
935 {
936 .fromsec = { DATA_SECTIONS, NULL },
937 .tosec = { ALL_EXIT_SECTIONS, NULL },
938 .mismatch = DATA_TO_ANY_EXIT,
939 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
940 },
941 /* Do not reference init code/data from devinit/cpuinit/meminit code/data */
942 {
943 .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
944 .tosec = { INIT_SECTIONS, NULL },
945 .mismatch = XXXINIT_TO_SOME_INIT,
946 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
947 },
948 /* Do not reference cpuinit code/data from meminit code/data */
949 {
950 .fromsec = { MEM_INIT_SECTIONS, NULL },
951 .tosec = { CPU_INIT_SECTIONS, NULL },
952 .mismatch = XXXINIT_TO_SOME_INIT,
953 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
954 },
955 /* Do not reference meminit code/data from cpuinit code/data */
956 {
957 .fromsec = { CPU_INIT_SECTIONS, NULL },
958 .tosec = { MEM_INIT_SECTIONS, NULL },
959 .mismatch = XXXINIT_TO_SOME_INIT,
960 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
961 },
962 /* Do not reference exit code/data from devexit/cpuexit/memexit code/data */
963 {
964 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
965 .tosec = { EXIT_SECTIONS, NULL },
966 .mismatch = XXXEXIT_TO_SOME_EXIT,
967 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
968 },
969 /* Do not reference cpuexit code/data from memexit code/data */
970 {
971 .fromsec = { MEM_EXIT_SECTIONS, NULL },
972 .tosec = { CPU_EXIT_SECTIONS, NULL },
973 .mismatch = XXXEXIT_TO_SOME_EXIT,
974 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
975 },
976 /* Do not reference memexit code/data from cpuexit code/data */
977 {
978 .fromsec = { CPU_EXIT_SECTIONS, NULL },
979 .tosec = { MEM_EXIT_SECTIONS, NULL },
980 .mismatch = XXXEXIT_TO_SOME_EXIT,
981 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
982 },
983 /* Do not use exit code/data from init code */
984 {
985 .fromsec = { ALL_INIT_SECTIONS, NULL },
986 .tosec = { ALL_EXIT_SECTIONS, NULL },
987 .mismatch = ANY_INIT_TO_ANY_EXIT,
988 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
989 },
990 /* Do not use init code/data from exit code */
991 {
992 .fromsec = { ALL_EXIT_SECTIONS, NULL },
993 .tosec = { ALL_INIT_SECTIONS, NULL },
994 .mismatch = ANY_EXIT_TO_ANY_INIT,
995 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
996 },
997 /* Do not export init/exit functions or data */
998 {
999 .fromsec = { "__ksymtab*", NULL },
1000 .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
1001 .mismatch = EXPORT_TO_INIT_EXIT,
1002 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1003 }
1004 };
1005
1006 static const struct sectioncheck *section_mismatch(
1007 const char *fromsec, const char *tosec)
1008 {
1009 int i;
1010 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
1011 const struct sectioncheck *check = &sectioncheck[0];
1012
1013 for (i = 0; i < elems; i++) {
1014 if (match(fromsec, check->fromsec) &&
1015 match(tosec, check->tosec))
1016 return check;
1017 check++;
1018 }
1019 return NULL;
1020 }
1021
1022 /**
1023 * Whitelist to allow certain references to pass with no warning.
1024 *
1025 * Pattern 1:
1026 * If a module parameter is declared __initdata and permissions=0
1027 * then this is legal despite the warning generated.
1028 * We cannot see value of permissions here, so just ignore
1029 * this pattern.
1030 * The pattern is identified by:
1031 * tosec = .init.data
1032 * fromsec = .data*
1033 * atsym =__param*
1034 *
1035 * Pattern 1a:
1036 * module_param_call() ops can refer to __init set function if permissions=0
1037 * The pattern is identified by:
1038 * tosec = .init.text
1039 * fromsec = .data*
1040 * atsym = __param_ops_*
1041 *
1042 * Pattern 2:
1043 * Many drivers utilise a *driver container with references to
1044 * add, remove, probe functions etc.
1045 * These functions may often be marked __devinit and we do not want to
1046 * warn here.
1047 * the pattern is identified by:
1048 * tosec = init or exit section
1049 * fromsec = data section
1050 * atsym = *driver, *_template, *_sht, *_ops, *_probe,
1051 * *probe_one, *_console, *_timer
1052 *
1053 * Pattern 3:
1054 * Whitelist all references from .head.text to any init section
1055 *
1056 * Pattern 4:
1057 * Some symbols belong to init section but still it is ok to reference
1058 * these from non-init sections as these symbols don't have any memory
1059 * allocated for them and symbol address and value are same. So even
1060 * if init section is freed, its ok to reference those symbols.
1061 * For ex. symbols marking the init section boundaries.
1062 * This pattern is identified by
1063 * refsymname = __init_begin, _sinittext, _einittext
1064 *
1065 **/
1066 static int secref_whitelist(const struct sectioncheck *mismatch,
1067 const char *fromsec, const char *fromsym,
1068 const char *tosec, const char *tosym)
1069 {
1070 /* Check for pattern 1 */
1071 if (match(tosec, init_data_sections) &&
1072 match(fromsec, data_sections) &&
1073 (strncmp(fromsym, "__param", strlen("__param")) == 0))
1074 return 0;
1075
1076 /* Check for pattern 1a */
1077 if (strcmp(tosec, ".init.text") == 0 &&
1078 match(fromsec, data_sections) &&
1079 (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0))
1080 return 0;
1081
1082 /* Check for pattern 2 */
1083 if (match(tosec, init_exit_sections) &&
1084 match(fromsec, data_sections) &&
1085 match(fromsym, mismatch->symbol_white_list))
1086 return 0;
1087
1088 /* Check for pattern 3 */
1089 if (match(fromsec, head_sections) &&
1090 match(tosec, init_sections))
1091 return 0;
1092
1093 /* Check for pattern 4 */
1094 if (match(tosym, linker_symbols))
1095 return 0;
1096
1097 return 1;
1098 }
1099
1100 /**
1101 * Find symbol based on relocation record info.
1102 * In some cases the symbol supplied is a valid symbol so
1103 * return refsym. If st_name != 0 we assume this is a valid symbol.
1104 * In other cases the symbol needs to be looked up in the symbol table
1105 * based on section and address.
1106 * **/
1107 static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
1108 Elf_Sym *relsym)
1109 {
1110 Elf_Sym *sym;
1111 Elf_Sym *near = NULL;
1112 Elf64_Sword distance = 20;
1113 Elf64_Sword d;
1114 unsigned int relsym_secindex;
1115
1116 if (relsym->st_name != 0)
1117 return relsym;
1118
1119 relsym_secindex = get_secindex(elf, relsym);
1120 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1121 if (get_secindex(elf, sym) != relsym_secindex)
1122 continue;
1123 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
1124 continue;
1125 if (sym->st_value == addr)
1126 return sym;
1127 /* Find a symbol nearby - addr are maybe negative */
1128 d = sym->st_value - addr;
1129 if (d < 0)
1130 d = addr - sym->st_value;
1131 if (d < distance) {
1132 distance = d;
1133 near = sym;
1134 }
1135 }
1136 /* We need a close match */
1137 if (distance < 20)
1138 return near;
1139 else
1140 return NULL;
1141 }
1142
1143 static inline int is_arm_mapping_symbol(const char *str)
1144 {
1145 return str[0] == '$' && strchr("atd", str[1])
1146 && (str[2] == '\0' || str[2] == '.');
1147 }
1148
1149 /*
1150 * If there's no name there, ignore it; likewise, ignore it if it's
1151 * one of the magic symbols emitted used by current ARM tools.
1152 *
1153 * Otherwise if find_symbols_between() returns those symbols, they'll
1154 * fail the whitelist tests and cause lots of false alarms ... fixable
1155 * only by merging __exit and __init sections into __text, bloating
1156 * the kernel (which is especially evil on embedded platforms).
1157 */
1158 static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
1159 {
1160 const char *name = elf->strtab + sym->st_name;
1161
1162 if (!name || !strlen(name))
1163 return 0;
1164 return !is_arm_mapping_symbol(name);
1165 }
1166
1167 /*
1168 * Find symbols before or equal addr and after addr - in the section sec.
1169 * If we find two symbols with equal offset prefer one with a valid name.
1170 * The ELF format may have a better way to detect what type of symbol
1171 * it is, but this works for now.
1172 **/
1173 static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
1174 const char *sec)
1175 {
1176 Elf_Sym *sym;
1177 Elf_Sym *near = NULL;
1178 Elf_Addr distance = ~0;
1179
1180 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1181 const char *symsec;
1182
1183 if (is_shndx_special(sym->st_shndx))
1184 continue;
1185 symsec = sec_name(elf, get_secindex(elf, sym));
1186 if (strcmp(symsec, sec) != 0)
1187 continue;
1188 if (!is_valid_name(elf, sym))
1189 continue;
1190 if (sym->st_value <= addr) {
1191 if ((addr - sym->st_value) < distance) {
1192 distance = addr - sym->st_value;
1193 near = sym;
1194 } else if ((addr - sym->st_value) == distance) {
1195 near = sym;
1196 }
1197 }
1198 }
1199 return near;
1200 }
1201
1202 /*
1203 * Convert a section name to the function/data attribute
1204 * .init.text => __init
1205 * .cpuinit.data => __cpudata
1206 * .memexitconst => __memconst
1207 * etc.
1208 *
1209 * The memory of returned value has been allocated on a heap. The user of this
1210 * method should free it after usage.
1211 */
1212 static char *sec2annotation(const char *s)
1213 {
1214 if (match(s, init_exit_sections)) {
1215 char *p = malloc(20);
1216 char *r = p;
1217
1218 *p++ = '_';
1219 *p++ = '_';
1220 if (*s == '.')
1221 s++;
1222 while (*s && *s != '.')
1223 *p++ = *s++;
1224 *p = '\0';
1225 if (*s == '.')
1226 s++;
1227 if (strstr(s, "rodata") != NULL)
1228 strcat(p, "const ");
1229 else if (strstr(s, "data") != NULL)
1230 strcat(p, "data ");
1231 else
1232 strcat(p, " ");
1233 return r;
1234 } else {
1235 return strdup("");
1236 }
1237 }
1238
1239 static int is_function(Elf_Sym *sym)
1240 {
1241 if (sym)
1242 return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
1243 else
1244 return -1;
1245 }
1246
1247 static void print_section_list(const char * const list[20])
1248 {
1249 const char *const *s = list;
1250
1251 while (*s) {
1252 fprintf(stderr, "%s", *s);
1253 s++;
1254 if (*s)
1255 fprintf(stderr, ", ");
1256 }
1257 fprintf(stderr, "\n");
1258 }
1259
1260 /*
1261 * Print a warning about a section mismatch.
1262 * Try to find symbols near it so user can find it.
1263 * Check whitelist before warning - it may be a false positive.
1264 */
1265 static void report_sec_mismatch(const char *modname,
1266 const struct sectioncheck *mismatch,
1267 const char *fromsec,
1268 unsigned long long fromaddr,
1269 const char *fromsym,
1270 int from_is_func,
1271 const char *tosec, const char *tosym,
1272 int to_is_func)
1273 {
1274 const char *from, *from_p;
1275 const char *to, *to_p;
1276 char *prl_from;
1277 char *prl_to;
1278
1279 switch (from_is_func) {
1280 case 0: from = "variable"; from_p = ""; break;
1281 case 1: from = "function"; from_p = "()"; break;
1282 default: from = "(unknown reference)"; from_p = ""; break;
1283 }
1284 switch (to_is_func) {
1285 case 0: to = "variable"; to_p = ""; break;
1286 case 1: to = "function"; to_p = "()"; break;
1287 default: to = "(unknown reference)"; to_p = ""; break;
1288 }
1289
1290 sec_mismatch_count++;
1291 if (!sec_mismatch_verbose)
1292 return;
1293
1294 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1295 "to the %s %s:%s%s\n",
1296 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
1297 tosym, to_p);
1298
1299 switch (mismatch->mismatch) {
1300 case TEXT_TO_ANY_INIT:
1301 prl_from = sec2annotation(fromsec);
1302 prl_to = sec2annotation(tosec);
1303 fprintf(stderr,
1304 "The function %s%s() references\n"
1305 "the %s %s%s%s.\n"
1306 "This is often because %s lacks a %s\n"
1307 "annotation or the annotation of %s is wrong.\n",
1308 prl_from, fromsym,
1309 to, prl_to, tosym, to_p,
1310 fromsym, prl_to, tosym);
1311 free(prl_from);
1312 free(prl_to);
1313 break;
1314 case DATA_TO_ANY_INIT: {
1315 prl_to = sec2annotation(tosec);
1316 fprintf(stderr,
1317 "The variable %s references\n"
1318 "the %s %s%s%s\n"
1319 "If the reference is valid then annotate the\n"
1320 "variable with __init* or __refdata (see linux/init.h) "
1321 "or name the variable:\n",
1322 fromsym, to, prl_to, tosym, to_p);
1323 print_section_list(mismatch->symbol_white_list);
1324 free(prl_to);
1325 break;
1326 }
1327 case TEXT_TO_ANY_EXIT:
1328 prl_to = sec2annotation(tosec);
1329 fprintf(stderr,
1330 "The function %s() references a %s in an exit section.\n"
1331 "Often the %s %s%s has valid usage outside the exit section\n"
1332 "and the fix is to remove the %sannotation of %s.\n",
1333 fromsym, to, to, tosym, to_p, prl_to, tosym);
1334 free(prl_to);
1335 break;
1336 case DATA_TO_ANY_EXIT: {
1337 prl_to = sec2annotation(tosec);
1338 fprintf(stderr,
1339 "The variable %s references\n"
1340 "the %s %s%s%s\n"
1341 "If the reference is valid then annotate the\n"
1342 "variable with __exit* (see linux/init.h) or "
1343 "name the variable:\n",
1344 fromsym, to, prl_to, tosym, to_p);
1345 print_section_list(mismatch->symbol_white_list);
1346 free(prl_to);
1347 break;
1348 }
1349 case XXXINIT_TO_SOME_INIT:
1350 case XXXEXIT_TO_SOME_EXIT:
1351 prl_from = sec2annotation(fromsec);
1352 prl_to = sec2annotation(tosec);
1353 fprintf(stderr,
1354 "The %s %s%s%s references\n"
1355 "a %s %s%s%s.\n"
1356 "If %s is only used by %s then\n"
1357 "annotate %s with a matching annotation.\n",
1358 from, prl_from, fromsym, from_p,
1359 to, prl_to, tosym, to_p,
1360 tosym, fromsym, tosym);
1361 free(prl_from);
1362 free(prl_to);
1363 break;
1364 case ANY_INIT_TO_ANY_EXIT:
1365 prl_from = sec2annotation(fromsec);
1366 prl_to = sec2annotation(tosec);
1367 fprintf(stderr,
1368 "The %s %s%s%s references\n"
1369 "a %s %s%s%s.\n"
1370 "This is often seen when error handling "
1371 "in the init function\n"
1372 "uses functionality in the exit path.\n"
1373 "The fix is often to remove the %sannotation of\n"
1374 "%s%s so it may be used outside an exit section.\n",
1375 from, prl_from, fromsym, from_p,
1376 to, prl_to, tosym, to_p,
1377 prl_to, tosym, to_p);
1378 free(prl_from);
1379 free(prl_to);
1380 break;
1381 case ANY_EXIT_TO_ANY_INIT:
1382 prl_from = sec2annotation(fromsec);
1383 prl_to = sec2annotation(tosec);
1384 fprintf(stderr,
1385 "The %s %s%s%s references\n"
1386 "a %s %s%s%s.\n"
1387 "This is often seen when error handling "
1388 "in the exit function\n"
1389 "uses functionality in the init path.\n"
1390 "The fix is often to remove the %sannotation of\n"
1391 "%s%s so it may be used outside an init section.\n",
1392 from, prl_from, fromsym, from_p,
1393 to, prl_to, tosym, to_p,
1394 prl_to, tosym, to_p);
1395 free(prl_from);
1396 free(prl_to);
1397 break;
1398 case EXPORT_TO_INIT_EXIT:
1399 prl_to = sec2annotation(tosec);
1400 fprintf(stderr,
1401 "The symbol %s is exported and annotated %s\n"
1402 "Fix this by removing the %sannotation of %s "
1403 "or drop the export.\n",
1404 tosym, prl_to, prl_to, tosym);
1405 free(prl_to);
1406 break;
1407 }
1408 fprintf(stderr, "\n");
1409 }
1410
1411 static void check_section_mismatch(const char *modname, struct elf_info *elf,
1412 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1413 {
1414 const char *tosec;
1415 const struct sectioncheck *mismatch;
1416
1417 tosec = sec_name(elf, get_secindex(elf, sym));
1418 mismatch = section_mismatch(fromsec, tosec);
1419 if (mismatch) {
1420 Elf_Sym *to;
1421 Elf_Sym *from;
1422 const char *tosym;
1423 const char *fromsym;
1424
1425 from = find_elf_symbol2(elf, r->r_offset, fromsec);
1426 fromsym = sym_name(elf, from);
1427 to = find_elf_symbol(elf, r->r_addend, sym);
1428 tosym = sym_name(elf, to);
1429
1430 /* check whitelist - we may ignore it */
1431 if (secref_whitelist(mismatch,
1432 fromsec, fromsym, tosec, tosym)) {
1433 report_sec_mismatch(modname, mismatch,
1434 fromsec, r->r_offset, fromsym,
1435 is_function(from), tosec, tosym,
1436 is_function(to));
1437 }
1438 }
1439 }
1440
1441 static unsigned int *reloc_location(struct elf_info *elf,
1442 Elf_Shdr *sechdr, Elf_Rela *r)
1443 {
1444 Elf_Shdr *sechdrs = elf->sechdrs;
1445 int section = sechdr->sh_info;
1446
1447 return (void *)elf->hdr + sechdrs[section].sh_offset +
1448 r->r_offset;
1449 }
1450
1451 static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1452 {
1453 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1454 unsigned int *location = reloc_location(elf, sechdr, r);
1455
1456 switch (r_typ) {
1457 case R_386_32:
1458 r->r_addend = TO_NATIVE(*location);
1459 break;
1460 case R_386_PC32:
1461 r->r_addend = TO_NATIVE(*location) + 4;
1462 /* For CONFIG_RELOCATABLE=y */
1463 if (elf->hdr->e_type == ET_EXEC)
1464 r->r_addend += r->r_offset;
1465 break;
1466 }
1467 return 0;
1468 }
1469
1470 static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1471 {
1472 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1473
1474 switch (r_typ) {
1475 case R_ARM_ABS32:
1476 /* From ARM ABI: (S + A) | T */
1477 r->r_addend = (int)(long)
1478 (elf->symtab_start + ELF_R_SYM(r->r_info));
1479 break;
1480 case R_ARM_PC24:
1481 /* From ARM ABI: ((S + A) | T) - P */
1482 r->r_addend = (int)(long)(elf->hdr +
1483 sechdr->sh_offset +
1484 (r->r_offset - sechdr->sh_addr));
1485 break;
1486 default:
1487 return 1;
1488 }
1489 return 0;
1490 }
1491
1492 static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1493 {
1494 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1495 unsigned int *location = reloc_location(elf, sechdr, r);
1496 unsigned int inst;
1497
1498 if (r_typ == R_MIPS_HI16)
1499 return 1; /* skip this */
1500 inst = TO_NATIVE(*location);
1501 switch (r_typ) {
1502 case R_MIPS_LO16:
1503 r->r_addend = inst & 0xffff;
1504 break;
1505 case R_MIPS_26:
1506 r->r_addend = (inst & 0x03ffffff) << 2;
1507 break;
1508 case R_MIPS_32:
1509 r->r_addend = inst;
1510 break;
1511 }
1512 return 0;
1513 }
1514
1515 static void section_rela(const char *modname, struct elf_info *elf,
1516 Elf_Shdr *sechdr)
1517 {
1518 Elf_Sym *sym;
1519 Elf_Rela *rela;
1520 Elf_Rela r;
1521 unsigned int r_sym;
1522 const char *fromsec;
1523
1524 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
1525 Elf_Rela *stop = (void *)start + sechdr->sh_size;
1526
1527 fromsec = sech_name(elf, sechdr);
1528 fromsec += strlen(".rela");
1529 /* if from section (name) is know good then skip it */
1530 if (match(fromsec, section_white_list))
1531 return;
1532
1533 for (rela = start; rela < stop; rela++) {
1534 r.r_offset = TO_NATIVE(rela->r_offset);
1535 #if KERNEL_ELFCLASS == ELFCLASS64
1536 if (elf->hdr->e_machine == EM_MIPS) {
1537 unsigned int r_typ;
1538 r_sym = ELF64_MIPS_R_SYM(rela->r_info);
1539 r_sym = TO_NATIVE(r_sym);
1540 r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
1541 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1542 } else {
1543 r.r_info = TO_NATIVE(rela->r_info);
1544 r_sym = ELF_R_SYM(r.r_info);
1545 }
1546 #else
1547 r.r_info = TO_NATIVE(rela->r_info);
1548 r_sym = ELF_R_SYM(r.r_info);
1549 #endif
1550 r.r_addend = TO_NATIVE(rela->r_addend);
1551 sym = elf->symtab_start + r_sym;
1552 /* Skip special sections */
1553 if (is_shndx_special(sym->st_shndx))
1554 continue;
1555 check_section_mismatch(modname, elf, &r, sym, fromsec);
1556 }
1557 }
1558
1559 static void section_rel(const char *modname, struct elf_info *elf,
1560 Elf_Shdr *sechdr)
1561 {
1562 Elf_Sym *sym;
1563 Elf_Rel *rel;
1564 Elf_Rela r;
1565 unsigned int r_sym;
1566 const char *fromsec;
1567
1568 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
1569 Elf_Rel *stop = (void *)start + sechdr->sh_size;
1570
1571 fromsec = sech_name(elf, sechdr);
1572 fromsec += strlen(".rel");
1573 /* if from section (name) is know good then skip it */
1574 if (match(fromsec, section_white_list))
1575 return;
1576
1577 for (rel = start; rel < stop; rel++) {
1578 r.r_offset = TO_NATIVE(rel->r_offset);
1579 #if KERNEL_ELFCLASS == ELFCLASS64
1580 if (elf->hdr->e_machine == EM_MIPS) {
1581 unsigned int r_typ;
1582 r_sym = ELF64_MIPS_R_SYM(rel->r_info);
1583 r_sym = TO_NATIVE(r_sym);
1584 r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
1585 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1586 } else {
1587 r.r_info = TO_NATIVE(rel->r_info);
1588 r_sym = ELF_R_SYM(r.r_info);
1589 }
1590 #else
1591 r.r_info = TO_NATIVE(rel->r_info);
1592 r_sym = ELF_R_SYM(r.r_info);
1593 #endif
1594 r.r_addend = 0;
1595 switch (elf->hdr->e_machine) {
1596 case EM_386:
1597 if (addend_386_rel(elf, sechdr, &r))
1598 continue;
1599 break;
1600 case EM_ARM:
1601 if (addend_arm_rel(elf, sechdr, &r))
1602 continue;
1603 break;
1604 case EM_MIPS:
1605 if (addend_mips_rel(elf, sechdr, &r))
1606 continue;
1607 break;
1608 }
1609 sym = elf->symtab_start + r_sym;
1610 /* Skip special sections */
1611 if (is_shndx_special(sym->st_shndx))
1612 continue;
1613 check_section_mismatch(modname, elf, &r, sym, fromsec);
1614 }
1615 }
1616
1617 /**
1618 * A module includes a number of sections that are discarded
1619 * either when loaded or when used as built-in.
1620 * For loaded modules all functions marked __init and all data
1621 * marked __initdata will be discarded when the module has been initialized.
1622 * Likewise for modules used built-in the sections marked __exit
1623 * are discarded because __exit marked function are supposed to be called
1624 * only when a module is unloaded which never happens for built-in modules.
1625 * The check_sec_ref() function traverses all relocation records
1626 * to find all references to a section that reference a section that will
1627 * be discarded and warns about it.
1628 **/
1629 static void check_sec_ref(struct module *mod, const char *modname,
1630 struct elf_info *elf)
1631 {
1632 int i;
1633 Elf_Shdr *sechdrs = elf->sechdrs;
1634
1635 /* Walk through all sections */
1636 for (i = 0; i < elf->num_sections; i++) {
1637 check_section(modname, elf, &elf->sechdrs[i]);
1638 /* We want to process only relocation sections and not .init */
1639 if (sechdrs[i].sh_type == SHT_RELA)
1640 section_rela(modname, elf, &elf->sechdrs[i]);
1641 else if (sechdrs[i].sh_type == SHT_REL)
1642 section_rel(modname, elf, &elf->sechdrs[i]);
1643 }
1644 }
1645
1646 static void read_symbols(char *modname)
1647 {
1648 const char *symname;
1649 char *version;
1650 char *license;
1651 struct module *mod;
1652 struct elf_info info = { };
1653 Elf_Sym *sym;
1654
1655 if (!parse_elf(&info, modname))
1656 return;
1657
1658 mod = new_module(modname);
1659
1660 /* When there's no vmlinux, don't print warnings about
1661 * unresolved symbols (since there'll be too many ;) */
1662 if (is_vmlinux(modname)) {
1663 have_vmlinux = 1;
1664 mod->skip = 1;
1665 }
1666
1667 license = get_modinfo(info.modinfo, info.modinfo_len, "license");
1668 if (info.modinfo && !license && !is_vmlinux(modname))
1669 warn("modpost: missing MODULE_LICENSE() in %s\n"
1670 "see include/linux/module.h for "
1671 "more information\n", modname);
1672 while (license) {
1673 if (license_is_gpl_compatible(license))
1674 mod->gpl_compatible = 1;
1675 else {
1676 mod->gpl_compatible = 0;
1677 break;
1678 }
1679 license = get_next_modinfo(info.modinfo, info.modinfo_len,
1680 "license", license);
1681 }
1682
1683 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
1684 symname = info.strtab + sym->st_name;
1685
1686 handle_modversions(mod, &info, sym, symname);
1687 handle_moddevtable(mod, &info, sym, symname);
1688 }
1689 if (!is_vmlinux(modname) ||
1690 (is_vmlinux(modname) && vmlinux_section_warnings))
1691 check_sec_ref(mod, modname, &info);
1692
1693 version = get_modinfo(info.modinfo, info.modinfo_len, "version");
1694 if (version)
1695 maybe_frob_rcs_version(modname, version, info.modinfo,
1696 version - (char *)info.hdr);
1697 if (version || (all_versions && !is_vmlinux(modname)))
1698 get_src_version(modname, mod->srcversion,
1699 sizeof(mod->srcversion)-1);
1700
1701 parse_elf_finish(&info);
1702
1703 /* Our trick to get versioning for module struct etc. - it's
1704 * never passed as an argument to an exported function, so
1705 * the automatic versioning doesn't pick it up, but it's really
1706 * important anyhow */
1707 if (modversions)
1708 mod->unres = alloc_symbol("module_layout", 0, mod->unres);
1709 }
1710
1711 #define SZ 500
1712
1713 /* We first write the generated file into memory using the
1714 * following helper, then compare to the file on disk and
1715 * only update the later if anything changed */
1716
1717 void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
1718 const char *fmt, ...)
1719 {
1720 char tmp[SZ];
1721 int len;
1722 va_list ap;
1723
1724 va_start(ap, fmt);
1725 len = vsnprintf(tmp, SZ, fmt, ap);
1726 buf_write(buf, tmp, len);
1727 va_end(ap);
1728 }
1729
1730 void buf_write(struct buffer *buf, const char *s, int len)
1731 {
1732 if (buf->size - buf->pos < len) {
1733 buf->size += len + SZ;
1734 buf->p = realloc(buf->p, buf->size);
1735 }
1736 strncpy(buf->p + buf->pos, s, len);
1737 buf->pos += len;
1738 }
1739
1740 static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
1741 {
1742 const char *e = is_vmlinux(m) ?"":".ko";
1743
1744 switch (exp) {
1745 case export_gpl:
1746 fatal("modpost: GPL-incompatible module %s%s "
1747 "uses GPL-only symbol '%s'\n", m, e, s);
1748 break;
1749 case export_unused_gpl:
1750 fatal("modpost: GPL-incompatible module %s%s "
1751 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
1752 break;
1753 case export_gpl_future:
1754 warn("modpost: GPL-incompatible module %s%s "
1755 "uses future GPL-only symbol '%s'\n", m, e, s);
1756 break;
1757 case export_plain:
1758 case export_unused:
1759 case export_unknown:
1760 /* ignore */
1761 break;
1762 }
1763 }
1764
1765 static void check_for_unused(enum export exp, const char *m, const char *s)
1766 {
1767 const char *e = is_vmlinux(m) ?"":".ko";
1768
1769 switch (exp) {
1770 case export_unused:
1771 case export_unused_gpl:
1772 warn("modpost: module %s%s "
1773 "uses symbol '%s' marked UNUSED\n", m, e, s);
1774 break;
1775 default:
1776 /* ignore */
1777 break;
1778 }
1779 }
1780
1781 static void check_exports(struct module *mod)
1782 {
1783 struct symbol *s, *exp;
1784
1785 for (s = mod->unres; s; s = s->next) {
1786 const char *basename;
1787 exp = find_symbol(s->name);
1788 if (!exp || exp->module == mod)
1789 continue;
1790 basename = strrchr(mod->name, '/');
1791 if (basename)
1792 basename++;
1793 else
1794 basename = mod->name;
1795 if (!mod->gpl_compatible)
1796 check_for_gpl_usage(exp->export, basename, exp->name);
1797 check_for_unused(exp->export, basename, exp->name);
1798 }
1799 }
1800
1801 /**
1802 * Header for the generated file
1803 **/
1804 static void add_header(struct buffer *b, struct module *mod)
1805 {
1806 buf_printf(b, "#include <linux/module.h>\n");
1807 buf_printf(b, "#include <linux/vermagic.h>\n");
1808 buf_printf(b, "#include <linux/compiler.h>\n");
1809 buf_printf(b, "\n");
1810 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1811 buf_printf(b, "\n");
1812 buf_printf(b, "struct module __this_module\n");
1813 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
1814 buf_printf(b, " .name = KBUILD_MODNAME,\n");
1815 if (mod->has_init)
1816 buf_printf(b, " .init = init_module,\n");
1817 if (mod->has_cleanup)
1818 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
1819 " .exit = cleanup_module,\n"
1820 "#endif\n");
1821 buf_printf(b, " .arch = MODULE_ARCH_INIT,\n");
1822 buf_printf(b, "};\n");
1823 }
1824
1825 static void add_staging_flag(struct buffer *b, const char *name)
1826 {
1827 static const char *staging_dir = "drivers/staging";
1828
1829 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0)
1830 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
1831 }
1832
1833 /**
1834 * Record CRCs for unresolved symbols
1835 **/
1836 static int add_versions(struct buffer *b, struct module *mod)
1837 {
1838 struct symbol *s, *exp;
1839 int err = 0;
1840
1841 for (s = mod->unres; s; s = s->next) {
1842 exp = find_symbol(s->name);
1843 if (!exp || exp->module == mod) {
1844 if (have_vmlinux && !s->weak) {
1845 if (warn_unresolved) {
1846 warn("\"%s\" [%s.ko] undefined!\n",
1847 s->name, mod->name);
1848 } else {
1849 merror("\"%s\" [%s.ko] undefined!\n",
1850 s->name, mod->name);
1851 err = 1;
1852 }
1853 }
1854 continue;
1855 }
1856 s->module = exp->module;
1857 s->crc_valid = exp->crc_valid;
1858 s->crc = exp->crc;
1859 }
1860
1861 if (!modversions)
1862 return err;
1863
1864 buf_printf(b, "\n");
1865 buf_printf(b, "static const struct modversion_info ____versions[]\n");
1866 buf_printf(b, "__used\n");
1867 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n");
1868
1869 for (s = mod->unres; s; s = s->next) {
1870 if (!s->module)
1871 continue;
1872 if (!s->crc_valid) {
1873 warn("\"%s\" [%s.ko] has no CRC!\n",
1874 s->name, mod->name);
1875 continue;
1876 }
1877 buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name);
1878 }
1879
1880 buf_printf(b, "};\n");
1881
1882 return err;
1883 }
1884
1885 static void add_depends(struct buffer *b, struct module *mod,
1886 struct module *modules)
1887 {
1888 struct symbol *s;
1889 struct module *m;
1890 int first = 1;
1891
1892 for (m = modules; m; m = m->next)
1893 m->seen = is_vmlinux(m->name);
1894
1895 buf_printf(b, "\n");
1896 buf_printf(b, "static const char __module_depends[]\n");
1897 buf_printf(b, "__used\n");
1898 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n");
1899 buf_printf(b, "\"depends=");
1900 for (s = mod->unres; s; s = s->next) {
1901 const char *p;
1902 if (!s->module)
1903 continue;
1904
1905 if (s->module->seen)
1906 continue;
1907
1908 s->module->seen = 1;
1909 p = strrchr(s->module->name, '/');
1910 if (p)
1911 p++;
1912 else
1913 p = s->module->name;
1914 buf_printf(b, "%s%s", first ? "" : ",", p);
1915 first = 0;
1916 }
1917 buf_printf(b, "\";\n");
1918 }
1919
1920 static void add_srcversion(struct buffer *b, struct module *mod)
1921 {
1922 if (mod->srcversion[0]) {
1923 buf_printf(b, "\n");
1924 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
1925 mod->srcversion);
1926 }
1927 }
1928
1929 static void write_if_changed(struct buffer *b, const char *fname)
1930 {
1931 char *tmp;
1932 FILE *file;
1933 struct stat st;
1934
1935 file = fopen(fname, "r");
1936 if (!file)
1937 goto write;
1938
1939 if (fstat(fileno(file), &st) < 0)
1940 goto close_write;
1941
1942 if (st.st_size != b->pos)
1943 goto close_write;
1944
1945 tmp = NOFAIL(malloc(b->pos));
1946 if (fread(tmp, 1, b->pos, file) != b->pos)
1947 goto free_write;
1948
1949 if (memcmp(tmp, b->p, b->pos) != 0)
1950 goto free_write;
1951
1952 free(tmp);
1953 fclose(file);
1954 return;
1955
1956 free_write:
1957 free(tmp);
1958 close_write:
1959 fclose(file);
1960 write:
1961 file = fopen(fname, "w");
1962 if (!file) {
1963 perror(fname);
1964 exit(1);
1965 }
1966 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
1967 perror(fname);
1968 exit(1);
1969 }
1970 fclose(file);
1971 }
1972
1973 /* parse Module.symvers file. line format:
1974 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
1975 **/
1976 static void read_dump(const char *fname, unsigned int kernel)
1977 {
1978 unsigned long size, pos = 0;
1979 void *file = grab_file(fname, &size);
1980 char *line;
1981
1982 if (!file)
1983 /* No symbol versions, silently ignore */
1984 return;
1985
1986 while ((line = get_next_line(&pos, file, size))) {
1987 char *symname, *modname, *d, *export, *end;
1988 unsigned int crc;
1989 struct module *mod;
1990 struct symbol *s;
1991
1992 if (!(symname = strchr(line, '\t')))
1993 goto fail;
1994 *symname++ = '\0';
1995 if (!(modname = strchr(symname, '\t')))
1996 goto fail;
1997 *modname++ = '\0';
1998 if ((export = strchr(modname, '\t')) != NULL)
1999 *export++ = '\0';
2000 if (export && ((end = strchr(export, '\t')) != NULL))
2001 *end = '\0';
2002 crc = strtoul(line, &d, 16);
2003 if (*symname == '\0' || *modname == '\0' || *d != '\0')
2004 goto fail;
2005 mod = find_module(modname);
2006 if (!mod) {
2007 if (is_vmlinux(modname))
2008 have_vmlinux = 1;
2009 mod = new_module(modname);
2010 mod->skip = 1;
2011 }
2012 s = sym_add_exported(symname, mod, export_no(export));
2013 s->kernel = kernel;
2014 s->preloaded = 1;
2015 sym_update_crc(symname, mod, crc, export_no(export));
2016 }
2017 return;
2018 fail:
2019 fatal("parse error in symbol dump file\n");
2020 }
2021
2022 /* For normal builds always dump all symbols.
2023 * For external modules only dump symbols
2024 * that are not read from kernel Module.symvers.
2025 **/
2026 static int dump_sym(struct symbol *sym)
2027 {
2028 if (!external_module)
2029 return 1;
2030 if (sym->vmlinux || sym->kernel)
2031 return 0;
2032 return 1;
2033 }
2034
2035 static void write_dump(const char *fname)
2036 {
2037 struct buffer buf = { };
2038 struct symbol *symbol;
2039 int n;
2040
2041 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
2042 symbol = symbolhash[n];
2043 while (symbol) {
2044 if (dump_sym(symbol))
2045 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
2046 symbol->crc, symbol->name,
2047 symbol->module->name,
2048 export_str(symbol->export));
2049 symbol = symbol->next;
2050 }
2051 }
2052 write_if_changed(&buf, fname);
2053 }
2054
2055 struct ext_sym_list {
2056 struct ext_sym_list *next;
2057 const char *file;
2058 };
2059
2060 int main(int argc, char **argv)
2061 {
2062 struct module *mod;
2063 struct buffer buf = { };
2064 char *kernel_read = NULL, *module_read = NULL;
2065 char *dump_write = NULL;
2066 int opt;
2067 int err;
2068 struct ext_sym_list *extsym_iter;
2069 struct ext_sym_list *extsym_start = NULL;
2070
2071 while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) {
2072 switch (opt) {
2073 case 'i':
2074 kernel_read = optarg;
2075 break;
2076 case 'I':
2077 module_read = optarg;
2078 external_module = 1;
2079 break;
2080 case 'c':
2081 cross_build = 1;
2082 break;
2083 case 'e':
2084 external_module = 1;
2085 extsym_iter =
2086 NOFAIL(malloc(sizeof(*extsym_iter)));
2087 extsym_iter->next = extsym_start;
2088 extsym_iter->file = optarg;
2089 extsym_start = extsym_iter;
2090 break;
2091 case 'm':
2092 modversions = 1;
2093 break;
2094 case 'o':
2095 dump_write = optarg;
2096 break;
2097 case 'a':
2098 all_versions = 1;
2099 break;
2100 case 's':
2101 vmlinux_section_warnings = 0;
2102 break;
2103 case 'S':
2104 sec_mismatch_verbose = 0;
2105 break;
2106 case 'w':
2107 warn_unresolved = 1;
2108 break;
2109 default:
2110 exit(1);
2111 }
2112 }
2113
2114 if (kernel_read)
2115 read_dump(kernel_read, 1);
2116 if (module_read)
2117 read_dump(module_read, 0);
2118 while (extsym_start) {
2119 read_dump(extsym_start->file, 0);
2120 extsym_iter = extsym_start->next;
2121 free(extsym_start);
2122 extsym_start = extsym_iter;
2123 }
2124
2125 while (optind < argc)
2126 read_symbols(argv[optind++]);
2127
2128 for (mod = modules; mod; mod = mod->next) {
2129 if (mod->skip)
2130 continue;
2131 check_exports(mod);
2132 }
2133
2134 err = 0;
2135
2136 for (mod = modules; mod; mod = mod->next) {
2137 char fname[strlen(mod->name) + 10];
2138
2139 if (mod->skip)
2140 continue;
2141
2142 buf.pos = 0;
2143
2144 add_header(&buf, mod);
2145 add_staging_flag(&buf, mod->name);
2146 err |= add_versions(&buf, mod);
2147 add_depends(&buf, mod, modules);
2148 add_moddevtable(&buf, mod);
2149 add_srcversion(&buf, mod);
2150
2151 sprintf(fname, "%s.mod.c", mod->name);
2152 write_if_changed(&buf, fname);
2153 }
2154
2155 if (dump_write)
2156 write_dump(dump_write);
2157 if (sec_mismatch_count && !sec_mismatch_verbose)
2158 warn("modpost: Found %d section mismatch(es).\n"
2159 "To see full details build your kernel with:\n"
2160 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
2161 sec_mismatch_count);
2162
2163 return err;
2164 }
linux-next