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Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
[mirror_ubuntu-eoan-kernel.git] / scripts / mod / modpost.c
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? */
27 int modversions = 0;
28 /* Warn about undefined symbols? (do so if we have vmlinux) */
29 int have_vmlinux = 0;
30 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */
31 static int all_versions = 0;
32 /* If we are modposting external module set to 1 */
33 static int external_module = 0;
34 /* Warn about section mismatch in vmlinux if set to 1 */
35 static int vmlinux_section_warnings = 1;
36 /* Only warn about unresolved symbols */
37 static int warn_unresolved = 0;
38 /* How a symbol is exported */
39 static int sec_mismatch_count = 0;
40 static int sec_mismatch_verbose = 1;
41 /* ignore missing files */
42 static int ignore_missing_files;
43
44 enum 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
51 PRINTF 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
64 PRINTF 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
75 PRINTF 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
86 static 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
94 static 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
108 void *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 */
117 static struct module *modules;
118
119 static 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
129 static 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
158 struct 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
172 static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
173
174 /* This is based on the hash agorithm from gdbm, via tdb */
175 static 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 **/
191 static 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 */
204 static 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
217 static 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
232 static 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
245 static const char *export_str(enum export ex)
246 {
247 return export_list[ex].str;
248 }
249
250 static 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
263 static const char *sec_name(struct elf_info *elf, int secindex);
264
265 #define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
266
267 static 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
285 static 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 **/
305 static struct symbol *sym_add_exported(const char *name, struct module *mod,
306 enum export export)
307 {
308 struct symbol *s = find_symbol(name);
309
310 if (!s) {
311 s = new_symbol(name, mod, export);
312 } else {
313 if (!s->preloaded) {
314 warn("%s: '%s' exported twice. Previous export "
315 "was in %s%s\n", mod->name, name,
316 s->module->name,
317 is_vmlinux(s->module->name) ?"":".ko");
318 } else {
319 /* In case Modules.symvers was out of date */
320 s->module = mod;
321 }
322 }
323 s->preloaded = 0;
324 s->vmlinux = is_vmlinux(mod->name);
325 s->kernel = 0;
326 s->export = export;
327 return s;
328 }
329
330 static 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
344 void *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
359 failed:
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 **/
371 char *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
400 void release_file(void *file, unsigned long size)
401 {
402 munmap(file, size);
403 }
404
405 static 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
569 static void parse_elf_finish(struct elf_info *info)
570 {
571 release_file(info->hdr, info->size);
572 }
573
574 static 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
605 static 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 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
627 break;
628 case SHN_UNDEF:
629 /* undefined symbol */
630 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
631 ELF_ST_BIND(sym->st_info) != STB_WEAK)
632 break;
633 if (ignore_undef_symbol(info, symname))
634 break;
635 /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
636 #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
637 /* add compatibility with older glibc */
638 #ifndef STT_SPARC_REGISTER
639 #define STT_SPARC_REGISTER STT_REGISTER
640 #endif
641 if (info->hdr->e_machine == EM_SPARC ||
642 info->hdr->e_machine == EM_SPARCV9) {
643 /* Ignore register directives. */
644 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
645 break;
646 if (symname[0] == '.') {
647 char *munged = strdup(symname);
648 munged[0] = '_';
649 munged[1] = toupper(munged[1]);
650 symname = munged;
651 }
652 }
653 #endif
654
655 #ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
656 if (symname[0] != '_')
657 break;
658 else
659 symname++;
660 #endif
661 mod->unres = alloc_symbol(symname,
662 ELF_ST_BIND(sym->st_info) == STB_WEAK,
663 mod->unres);
664 break;
665 default:
666 /* All exported symbols */
667 if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
668 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
669 export);
670 }
671 if (strcmp(symname, VMLINUX_SYMBOL_STR(init_module)) == 0)
672 mod->has_init = 1;
673 if (strcmp(symname, VMLINUX_SYMBOL_STR(cleanup_module)) == 0)
674 mod->has_cleanup = 1;
675 break;
676 }
677 }
678
679 /**
680 * Parse tag=value strings from .modinfo section
681 **/
682 static char *next_string(char *string, unsigned long *secsize)
683 {
684 /* Skip non-zero chars */
685 while (string[0]) {
686 string++;
687 if ((*secsize)-- <= 1)
688 return NULL;
689 }
690
691 /* Skip any zero padding. */
692 while (!string[0]) {
693 string++;
694 if ((*secsize)-- <= 1)
695 return NULL;
696 }
697 return string;
698 }
699
700 static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
701 const char *tag, char *info)
702 {
703 char *p;
704 unsigned int taglen = strlen(tag);
705 unsigned long size = modinfo_len;
706
707 if (info) {
708 size -= info - (char *)modinfo;
709 modinfo = next_string(info, &size);
710 }
711
712 for (p = modinfo; p; p = next_string(p, &size)) {
713 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
714 return p + taglen + 1;
715 }
716 return NULL;
717 }
718
719 static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
720 const char *tag)
721
722 {
723 return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
724 }
725
726 /**
727 * Test if string s ends in string sub
728 * return 0 if match
729 **/
730 static int strrcmp(const char *s, const char *sub)
731 {
732 int slen, sublen;
733
734 if (!s || !sub)
735 return 1;
736
737 slen = strlen(s);
738 sublen = strlen(sub);
739
740 if ((slen == 0) || (sublen == 0))
741 return 1;
742
743 if (sublen > slen)
744 return 1;
745
746 return memcmp(s + slen - sublen, sub, sublen);
747 }
748
749 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
750 {
751 if (sym)
752 return elf->strtab + sym->st_name;
753 else
754 return "(unknown)";
755 }
756
757 static const char *sec_name(struct elf_info *elf, int secindex)
758 {
759 Elf_Shdr *sechdrs = elf->sechdrs;
760 return (void *)elf->hdr +
761 elf->sechdrs[elf->secindex_strings].sh_offset +
762 sechdrs[secindex].sh_name;
763 }
764
765 static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr)
766 {
767 return (void *)elf->hdr +
768 elf->sechdrs[elf->secindex_strings].sh_offset +
769 sechdr->sh_name;
770 }
771
772 /* if sym is empty or point to a string
773 * like ".[0-9]+" then return 1.
774 * This is the optional prefix added by ld to some sections
775 */
776 static int number_prefix(const char *sym)
777 {
778 if (*sym++ == '\0')
779 return 1;
780 if (*sym != '.')
781 return 0;
782 do {
783 char c = *sym++;
784 if (c < '0' || c > '9')
785 return 0;
786 } while (*sym);
787 return 1;
788 }
789
790 /* The pattern is an array of simple patterns.
791 * "foo" will match an exact string equal to "foo"
792 * "*foo" will match a string that ends with "foo"
793 * "foo*" will match a string that begins with "foo"
794 * "foo$" will match a string equal to "foo" or "foo.1"
795 * where the '1' can be any number including several digits.
796 * The $ syntax is for sections where ld append a dot number
797 * to make section name unique.
798 */
799 static int match(const char *sym, const char * const pat[])
800 {
801 const char *p;
802 while (*pat) {
803 p = *pat++;
804 const char *endp = p + strlen(p) - 1;
805
806 /* "*foo" */
807 if (*p == '*') {
808 if (strrcmp(sym, p + 1) == 0)
809 return 1;
810 }
811 /* "foo*" */
812 else if (*endp == '*') {
813 if (strncmp(sym, p, strlen(p) - 1) == 0)
814 return 1;
815 }
816 /* "foo$" */
817 else if (*endp == '$') {
818 if (strncmp(sym, p, strlen(p) - 1) == 0) {
819 if (number_prefix(sym + strlen(p) - 1))
820 return 1;
821 }
822 }
823 /* no wildcards */
824 else {
825 if (strcmp(p, sym) == 0)
826 return 1;
827 }
828 }
829 /* no match */
830 return 0;
831 }
832
833 /* sections that we do not want to do full section mismatch check on */
834 static const char *section_white_list[] =
835 {
836 ".comment*",
837 ".debug*",
838 ".cranges", /* sh64 */
839 ".zdebug*", /* Compressed debug sections. */
840 ".GCC-command-line", /* mn10300 */
841 ".GCC.command.line", /* record-gcc-switches, non mn10300 */
842 ".mdebug*", /* alpha, score, mips etc. */
843 ".pdr", /* alpha, score, mips etc. */
844 ".stab*",
845 ".note*",
846 ".got*",
847 ".toc*",
848 ".xt.prop", /* xtensa */
849 ".xt.lit", /* xtensa */
850 ".arcextmap*", /* arc */
851 ".gnu.linkonce.arcext*", /* arc : modules */
852 NULL
853 };
854
855 /*
856 * This is used to find sections missing the SHF_ALLOC flag.
857 * The cause of this is often a section specified in assembler
858 * without "ax" / "aw".
859 */
860 static void check_section(const char *modname, struct elf_info *elf,
861 Elf_Shdr *sechdr)
862 {
863 const char *sec = sech_name(elf, sechdr);
864
865 if (sechdr->sh_type == SHT_PROGBITS &&
866 !(sechdr->sh_flags & SHF_ALLOC) &&
867 !match(sec, section_white_list)) {
868 warn("%s (%s): unexpected non-allocatable section.\n"
869 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
870 "Note that for example <linux/init.h> contains\n"
871 "section definitions for use in .S files.\n\n",
872 modname, sec);
873 }
874 }
875
876
877
878 #define ALL_INIT_DATA_SECTIONS \
879 ".init.setup$", ".init.rodata$", ".meminit.rodata$", \
880 ".init.data$", ".meminit.data$"
881 #define ALL_EXIT_DATA_SECTIONS \
882 ".exit.data$", ".memexit.data$"
883
884 #define ALL_INIT_TEXT_SECTIONS \
885 ".init.text$", ".meminit.text$"
886 #define ALL_EXIT_TEXT_SECTIONS \
887 ".exit.text$", ".memexit.text$"
888
889 #define ALL_PCI_INIT_SECTIONS \
890 ".pci_fixup_early$", ".pci_fixup_header$", ".pci_fixup_final$", \
891 ".pci_fixup_enable$", ".pci_fixup_resume$", \
892 ".pci_fixup_resume_early$", ".pci_fixup_suspend$"
893
894 #define ALL_XXXINIT_SECTIONS MEM_INIT_SECTIONS
895 #define ALL_XXXEXIT_SECTIONS MEM_EXIT_SECTIONS
896
897 #define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
898 #define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
899
900 #define DATA_SECTIONS ".data$", ".data.rel$"
901 #define TEXT_SECTIONS ".text$", ".text.unlikely$"
902
903 #define INIT_SECTIONS ".init.*"
904 #define MEM_INIT_SECTIONS ".meminit.*"
905
906 #define EXIT_SECTIONS ".exit.*"
907 #define MEM_EXIT_SECTIONS ".memexit.*"
908
909 /* init data sections */
910 static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL };
911
912 /* all init sections */
913 static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL };
914
915 /* All init and exit sections (code + data) */
916 static const char *init_exit_sections[] =
917 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
918
919 /* data section */
920 static const char *data_sections[] = { DATA_SECTIONS, NULL };
921
922
923 /* symbols in .data that may refer to init/exit sections */
924 #define DEFAULT_SYMBOL_WHITE_LIST \
925 "*driver", \
926 "*_template", /* scsi uses *_template a lot */ \
927 "*_timer", /* arm uses ops structures named _timer a lot */ \
928 "*_sht", /* scsi also used *_sht to some extent */ \
929 "*_ops", \
930 "*_probe", \
931 "*_probe_one", \
932 "*_console"
933
934 static const char *head_sections[] = { ".head.text*", NULL };
935 static const char *linker_symbols[] =
936 { "__init_begin", "_sinittext", "_einittext", NULL };
937
938 enum mismatch {
939 TEXT_TO_ANY_INIT,
940 DATA_TO_ANY_INIT,
941 TEXT_TO_ANY_EXIT,
942 DATA_TO_ANY_EXIT,
943 XXXINIT_TO_SOME_INIT,
944 XXXEXIT_TO_SOME_EXIT,
945 ANY_INIT_TO_ANY_EXIT,
946 ANY_EXIT_TO_ANY_INIT,
947 EXPORT_TO_INIT_EXIT,
948 };
949
950 struct sectioncheck {
951 const char *fromsec[20];
952 const char *tosec[20];
953 enum mismatch mismatch;
954 const char *symbol_white_list[20];
955 };
956
957 const struct sectioncheck sectioncheck[] = {
958 /* Do not reference init/exit code/data from
959 * normal code and data
960 */
961 {
962 .fromsec = { TEXT_SECTIONS, NULL },
963 .tosec = { ALL_INIT_SECTIONS, NULL },
964 .mismatch = TEXT_TO_ANY_INIT,
965 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
966 },
967 {
968 .fromsec = { DATA_SECTIONS, NULL },
969 .tosec = { ALL_XXXINIT_SECTIONS, NULL },
970 .mismatch = DATA_TO_ANY_INIT,
971 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
972 },
973 {
974 .fromsec = { DATA_SECTIONS, NULL },
975 .tosec = { INIT_SECTIONS, NULL },
976 .mismatch = DATA_TO_ANY_INIT,
977 .symbol_white_list = {
978 "*_template", "*_timer", "*_sht", "*_ops",
979 "*_probe", "*_probe_one", "*_console", NULL
980 },
981 },
982 {
983 .fromsec = { TEXT_SECTIONS, NULL },
984 .tosec = { ALL_EXIT_SECTIONS, NULL },
985 .mismatch = TEXT_TO_ANY_EXIT,
986 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
987 },
988 {
989 .fromsec = { DATA_SECTIONS, NULL },
990 .tosec = { ALL_EXIT_SECTIONS, NULL },
991 .mismatch = DATA_TO_ANY_EXIT,
992 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
993 },
994 /* Do not reference init code/data from meminit code/data */
995 {
996 .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
997 .tosec = { INIT_SECTIONS, NULL },
998 .mismatch = XXXINIT_TO_SOME_INIT,
999 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1000 },
1001 /* Do not reference exit code/data from memexit code/data */
1002 {
1003 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
1004 .tosec = { EXIT_SECTIONS, NULL },
1005 .mismatch = XXXEXIT_TO_SOME_EXIT,
1006 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1007 },
1008 /* Do not use exit code/data from init code */
1009 {
1010 .fromsec = { ALL_INIT_SECTIONS, NULL },
1011 .tosec = { ALL_EXIT_SECTIONS, NULL },
1012 .mismatch = ANY_INIT_TO_ANY_EXIT,
1013 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1014 },
1015 /* Do not use init code/data from exit code */
1016 {
1017 .fromsec = { ALL_EXIT_SECTIONS, NULL },
1018 .tosec = { ALL_INIT_SECTIONS, NULL },
1019 .mismatch = ANY_EXIT_TO_ANY_INIT,
1020 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1021 },
1022 {
1023 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
1024 .tosec = { INIT_SECTIONS, NULL },
1025 .mismatch = ANY_INIT_TO_ANY_EXIT,
1026 .symbol_white_list = { NULL },
1027 },
1028 /* Do not export init/exit functions or data */
1029 {
1030 .fromsec = { "__ksymtab*", NULL },
1031 .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
1032 .mismatch = EXPORT_TO_INIT_EXIT,
1033 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1034 }
1035 };
1036
1037 static const struct sectioncheck *section_mismatch(
1038 const char *fromsec, const char *tosec)
1039 {
1040 int i;
1041 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
1042 const struct sectioncheck *check = &sectioncheck[0];
1043
1044 for (i = 0; i < elems; i++) {
1045 if (match(fromsec, check->fromsec) &&
1046 match(tosec, check->tosec))
1047 return check;
1048 check++;
1049 }
1050 return NULL;
1051 }
1052
1053 /**
1054 * Whitelist to allow certain references to pass with no warning.
1055 *
1056 * Pattern 1:
1057 * If a module parameter is declared __initdata and permissions=0
1058 * then this is legal despite the warning generated.
1059 * We cannot see value of permissions here, so just ignore
1060 * this pattern.
1061 * The pattern is identified by:
1062 * tosec = .init.data
1063 * fromsec = .data*
1064 * atsym =__param*
1065 *
1066 * Pattern 1a:
1067 * module_param_call() ops can refer to __init set function if permissions=0
1068 * The pattern is identified by:
1069 * tosec = .init.text
1070 * fromsec = .data*
1071 * atsym = __param_ops_*
1072 *
1073 * Pattern 2:
1074 * Many drivers utilise a *driver container with references to
1075 * add, remove, probe functions etc.
1076 * the pattern is identified by:
1077 * tosec = init or exit section
1078 * fromsec = data section
1079 * atsym = *driver, *_template, *_sht, *_ops, *_probe,
1080 * *probe_one, *_console, *_timer
1081 *
1082 * Pattern 3:
1083 * Whitelist all references from .head.text to any init section
1084 *
1085 * Pattern 4:
1086 * Some symbols belong to init section but still it is ok to reference
1087 * these from non-init sections as these symbols don't have any memory
1088 * allocated for them and symbol address and value are same. So even
1089 * if init section is freed, its ok to reference those symbols.
1090 * For ex. symbols marking the init section boundaries.
1091 * This pattern is identified by
1092 * refsymname = __init_begin, _sinittext, _einittext
1093 *
1094 **/
1095 static int secref_whitelist(const struct sectioncheck *mismatch,
1096 const char *fromsec, const char *fromsym,
1097 const char *tosec, const char *tosym)
1098 {
1099 /* Check for pattern 1 */
1100 if (match(tosec, init_data_sections) &&
1101 match(fromsec, data_sections) &&
1102 (strncmp(fromsym, "__param", strlen("__param")) == 0))
1103 return 0;
1104
1105 /* Check for pattern 1a */
1106 if (strcmp(tosec, ".init.text") == 0 &&
1107 match(fromsec, data_sections) &&
1108 (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0))
1109 return 0;
1110
1111 /* Check for pattern 2 */
1112 if (match(tosec, init_exit_sections) &&
1113 match(fromsec, data_sections) &&
1114 match(fromsym, mismatch->symbol_white_list))
1115 return 0;
1116
1117 /* Check for pattern 3 */
1118 if (match(fromsec, head_sections) &&
1119 match(tosec, init_sections))
1120 return 0;
1121
1122 /* Check for pattern 4 */
1123 if (match(tosym, linker_symbols))
1124 return 0;
1125
1126 return 1;
1127 }
1128
1129 /**
1130 * Find symbol based on relocation record info.
1131 * In some cases the symbol supplied is a valid symbol so
1132 * return refsym. If st_name != 0 we assume this is a valid symbol.
1133 * In other cases the symbol needs to be looked up in the symbol table
1134 * based on section and address.
1135 * **/
1136 static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
1137 Elf_Sym *relsym)
1138 {
1139 Elf_Sym *sym;
1140 Elf_Sym *near = NULL;
1141 Elf64_Sword distance = 20;
1142 Elf64_Sword d;
1143 unsigned int relsym_secindex;
1144
1145 if (relsym->st_name != 0)
1146 return relsym;
1147
1148 relsym_secindex = get_secindex(elf, relsym);
1149 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1150 if (get_secindex(elf, sym) != relsym_secindex)
1151 continue;
1152 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
1153 continue;
1154 if (sym->st_value == addr)
1155 return sym;
1156 /* Find a symbol nearby - addr are maybe negative */
1157 d = sym->st_value - addr;
1158 if (d < 0)
1159 d = addr - sym->st_value;
1160 if (d < distance) {
1161 distance = d;
1162 near = sym;
1163 }
1164 }
1165 /* We need a close match */
1166 if (distance < 20)
1167 return near;
1168 else
1169 return NULL;
1170 }
1171
1172 static inline int is_arm_mapping_symbol(const char *str)
1173 {
1174 return str[0] == '$' && strchr("atd", str[1])
1175 && (str[2] == '\0' || str[2] == '.');
1176 }
1177
1178 /*
1179 * If there's no name there, ignore it; likewise, ignore it if it's
1180 * one of the magic symbols emitted used by current ARM tools.
1181 *
1182 * Otherwise if find_symbols_between() returns those symbols, they'll
1183 * fail the whitelist tests and cause lots of false alarms ... fixable
1184 * only by merging __exit and __init sections into __text, bloating
1185 * the kernel (which is especially evil on embedded platforms).
1186 */
1187 static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
1188 {
1189 const char *name = elf->strtab + sym->st_name;
1190
1191 if (!name || !strlen(name))
1192 return 0;
1193 return !is_arm_mapping_symbol(name);
1194 }
1195
1196 /*
1197 * Find symbols before or equal addr and after addr - in the section sec.
1198 * If we find two symbols with equal offset prefer one with a valid name.
1199 * The ELF format may have a better way to detect what type of symbol
1200 * it is, but this works for now.
1201 **/
1202 static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
1203 const char *sec)
1204 {
1205 Elf_Sym *sym;
1206 Elf_Sym *near = NULL;
1207 Elf_Addr distance = ~0;
1208
1209 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1210 const char *symsec;
1211
1212 if (is_shndx_special(sym->st_shndx))
1213 continue;
1214 symsec = sec_name(elf, get_secindex(elf, sym));
1215 if (strcmp(symsec, sec) != 0)
1216 continue;
1217 if (!is_valid_name(elf, sym))
1218 continue;
1219 if (sym->st_value <= addr) {
1220 if ((addr - sym->st_value) < distance) {
1221 distance = addr - sym->st_value;
1222 near = sym;
1223 } else if ((addr - sym->st_value) == distance) {
1224 near = sym;
1225 }
1226 }
1227 }
1228 return near;
1229 }
1230
1231 /*
1232 * Convert a section name to the function/data attribute
1233 * .init.text => __init
1234 * .memexitconst => __memconst
1235 * etc.
1236 *
1237 * The memory of returned value has been allocated on a heap. The user of this
1238 * method should free it after usage.
1239 */
1240 static char *sec2annotation(const char *s)
1241 {
1242 if (match(s, init_exit_sections)) {
1243 char *p = malloc(20);
1244 char *r = p;
1245
1246 *p++ = '_';
1247 *p++ = '_';
1248 if (*s == '.')
1249 s++;
1250 while (*s && *s != '.')
1251 *p++ = *s++;
1252 *p = '\0';
1253 if (*s == '.')
1254 s++;
1255 if (strstr(s, "rodata") != NULL)
1256 strcat(p, "const ");
1257 else if (strstr(s, "data") != NULL)
1258 strcat(p, "data ");
1259 else
1260 strcat(p, " ");
1261 return r;
1262 } else {
1263 return strdup("");
1264 }
1265 }
1266
1267 static int is_function(Elf_Sym *sym)
1268 {
1269 if (sym)
1270 return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
1271 else
1272 return -1;
1273 }
1274
1275 static void print_section_list(const char * const list[20])
1276 {
1277 const char *const *s = list;
1278
1279 while (*s) {
1280 fprintf(stderr, "%s", *s);
1281 s++;
1282 if (*s)
1283 fprintf(stderr, ", ");
1284 }
1285 fprintf(stderr, "\n");
1286 }
1287
1288 /*
1289 * Print a warning about a section mismatch.
1290 * Try to find symbols near it so user can find it.
1291 * Check whitelist before warning - it may be a false positive.
1292 */
1293 static void report_sec_mismatch(const char *modname,
1294 const struct sectioncheck *mismatch,
1295 const char *fromsec,
1296 unsigned long long fromaddr,
1297 const char *fromsym,
1298 int from_is_func,
1299 const char *tosec, const char *tosym,
1300 int to_is_func)
1301 {
1302 const char *from, *from_p;
1303 const char *to, *to_p;
1304 char *prl_from;
1305 char *prl_to;
1306
1307 switch (from_is_func) {
1308 case 0: from = "variable"; from_p = ""; break;
1309 case 1: from = "function"; from_p = "()"; break;
1310 default: from = "(unknown reference)"; from_p = ""; break;
1311 }
1312 switch (to_is_func) {
1313 case 0: to = "variable"; to_p = ""; break;
1314 case 1: to = "function"; to_p = "()"; break;
1315 default: to = "(unknown reference)"; to_p = ""; break;
1316 }
1317
1318 sec_mismatch_count++;
1319 if (!sec_mismatch_verbose)
1320 return;
1321
1322 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1323 "to the %s %s:%s%s\n",
1324 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
1325 tosym, to_p);
1326
1327 switch (mismatch->mismatch) {
1328 case TEXT_TO_ANY_INIT:
1329 prl_from = sec2annotation(fromsec);
1330 prl_to = sec2annotation(tosec);
1331 fprintf(stderr,
1332 "The function %s%s() references\n"
1333 "the %s %s%s%s.\n"
1334 "This is often because %s lacks a %s\n"
1335 "annotation or the annotation of %s is wrong.\n",
1336 prl_from, fromsym,
1337 to, prl_to, tosym, to_p,
1338 fromsym, prl_to, tosym);
1339 free(prl_from);
1340 free(prl_to);
1341 break;
1342 case DATA_TO_ANY_INIT: {
1343 prl_to = sec2annotation(tosec);
1344 fprintf(stderr,
1345 "The variable %s references\n"
1346 "the %s %s%s%s\n"
1347 "If the reference is valid then annotate the\n"
1348 "variable with __init* or __refdata (see linux/init.h) "
1349 "or name the variable:\n",
1350 fromsym, to, prl_to, tosym, to_p);
1351 print_section_list(mismatch->symbol_white_list);
1352 free(prl_to);
1353 break;
1354 }
1355 case TEXT_TO_ANY_EXIT:
1356 prl_to = sec2annotation(tosec);
1357 fprintf(stderr,
1358 "The function %s() references a %s in an exit section.\n"
1359 "Often the %s %s%s has valid usage outside the exit section\n"
1360 "and the fix is to remove the %sannotation of %s.\n",
1361 fromsym, to, to, tosym, to_p, prl_to, tosym);
1362 free(prl_to);
1363 break;
1364 case DATA_TO_ANY_EXIT: {
1365 prl_to = sec2annotation(tosec);
1366 fprintf(stderr,
1367 "The variable %s references\n"
1368 "the %s %s%s%s\n"
1369 "If the reference is valid then annotate the\n"
1370 "variable with __exit* (see linux/init.h) or "
1371 "name the variable:\n",
1372 fromsym, to, prl_to, tosym, to_p);
1373 print_section_list(mismatch->symbol_white_list);
1374 free(prl_to);
1375 break;
1376 }
1377 case XXXINIT_TO_SOME_INIT:
1378 case XXXEXIT_TO_SOME_EXIT:
1379 prl_from = sec2annotation(fromsec);
1380 prl_to = sec2annotation(tosec);
1381 fprintf(stderr,
1382 "The %s %s%s%s references\n"
1383 "a %s %s%s%s.\n"
1384 "If %s is only used by %s then\n"
1385 "annotate %s with a matching annotation.\n",
1386 from, prl_from, fromsym, from_p,
1387 to, prl_to, tosym, to_p,
1388 tosym, fromsym, tosym);
1389 free(prl_from);
1390 free(prl_to);
1391 break;
1392 case ANY_INIT_TO_ANY_EXIT:
1393 prl_from = sec2annotation(fromsec);
1394 prl_to = sec2annotation(tosec);
1395 fprintf(stderr,
1396 "The %s %s%s%s references\n"
1397 "a %s %s%s%s.\n"
1398 "This is often seen when error handling "
1399 "in the init function\n"
1400 "uses functionality in the exit path.\n"
1401 "The fix is often to remove the %sannotation of\n"
1402 "%s%s so it may be used outside an exit section.\n",
1403 from, prl_from, fromsym, from_p,
1404 to, prl_to, tosym, to_p,
1405 prl_to, tosym, to_p);
1406 free(prl_from);
1407 free(prl_to);
1408 break;
1409 case ANY_EXIT_TO_ANY_INIT:
1410 prl_from = sec2annotation(fromsec);
1411 prl_to = sec2annotation(tosec);
1412 fprintf(stderr,
1413 "The %s %s%s%s references\n"
1414 "a %s %s%s%s.\n"
1415 "This is often seen when error handling "
1416 "in the exit function\n"
1417 "uses functionality in the init path.\n"
1418 "The fix is often to remove the %sannotation of\n"
1419 "%s%s so it may be used outside an init section.\n",
1420 from, prl_from, fromsym, from_p,
1421 to, prl_to, tosym, to_p,
1422 prl_to, tosym, to_p);
1423 free(prl_from);
1424 free(prl_to);
1425 break;
1426 case EXPORT_TO_INIT_EXIT:
1427 prl_to = sec2annotation(tosec);
1428 fprintf(stderr,
1429 "The symbol %s is exported and annotated %s\n"
1430 "Fix this by removing the %sannotation of %s "
1431 "or drop the export.\n",
1432 tosym, prl_to, prl_to, tosym);
1433 free(prl_to);
1434 break;
1435 }
1436 fprintf(stderr, "\n");
1437 }
1438
1439 static void check_section_mismatch(const char *modname, struct elf_info *elf,
1440 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1441 {
1442 const char *tosec;
1443 const struct sectioncheck *mismatch;
1444
1445 tosec = sec_name(elf, get_secindex(elf, sym));
1446 mismatch = section_mismatch(fromsec, tosec);
1447 if (mismatch) {
1448 Elf_Sym *to;
1449 Elf_Sym *from;
1450 const char *tosym;
1451 const char *fromsym;
1452
1453 from = find_elf_symbol2(elf, r->r_offset, fromsec);
1454 fromsym = sym_name(elf, from);
1455 to = find_elf_symbol(elf, r->r_addend, sym);
1456 tosym = sym_name(elf, to);
1457
1458 /* check whitelist - we may ignore it */
1459 if (secref_whitelist(mismatch,
1460 fromsec, fromsym, tosec, tosym)) {
1461 report_sec_mismatch(modname, mismatch,
1462 fromsec, r->r_offset, fromsym,
1463 is_function(from), tosec, tosym,
1464 is_function(to));
1465 }
1466 }
1467 }
1468
1469 static unsigned int *reloc_location(struct elf_info *elf,
1470 Elf_Shdr *sechdr, Elf_Rela *r)
1471 {
1472 Elf_Shdr *sechdrs = elf->sechdrs;
1473 int section = sechdr->sh_info;
1474
1475 return (void *)elf->hdr + sechdrs[section].sh_offset +
1476 r->r_offset;
1477 }
1478
1479 static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1480 {
1481 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1482 unsigned int *location = reloc_location(elf, sechdr, r);
1483
1484 switch (r_typ) {
1485 case R_386_32:
1486 r->r_addend = TO_NATIVE(*location);
1487 break;
1488 case R_386_PC32:
1489 r->r_addend = TO_NATIVE(*location) + 4;
1490 /* For CONFIG_RELOCATABLE=y */
1491 if (elf->hdr->e_type == ET_EXEC)
1492 r->r_addend += r->r_offset;
1493 break;
1494 }
1495 return 0;
1496 }
1497
1498 #ifndef R_ARM_CALL
1499 #define R_ARM_CALL 28
1500 #endif
1501 #ifndef R_ARM_JUMP24
1502 #define R_ARM_JUMP24 29
1503 #endif
1504
1505 static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1506 {
1507 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1508
1509 switch (r_typ) {
1510 case R_ARM_ABS32:
1511 /* From ARM ABI: (S + A) | T */
1512 r->r_addend = (int)(long)
1513 (elf->symtab_start + ELF_R_SYM(r->r_info));
1514 break;
1515 case R_ARM_PC24:
1516 case R_ARM_CALL:
1517 case R_ARM_JUMP24:
1518 /* From ARM ABI: ((S + A) | T) - P */
1519 r->r_addend = (int)(long)(elf->hdr +
1520 sechdr->sh_offset +
1521 (r->r_offset - sechdr->sh_addr));
1522 break;
1523 default:
1524 return 1;
1525 }
1526 return 0;
1527 }
1528
1529 static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1530 {
1531 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1532 unsigned int *location = reloc_location(elf, sechdr, r);
1533 unsigned int inst;
1534
1535 if (r_typ == R_MIPS_HI16)
1536 return 1; /* skip this */
1537 inst = TO_NATIVE(*location);
1538 switch (r_typ) {
1539 case R_MIPS_LO16:
1540 r->r_addend = inst & 0xffff;
1541 break;
1542 case R_MIPS_26:
1543 r->r_addend = (inst & 0x03ffffff) << 2;
1544 break;
1545 case R_MIPS_32:
1546 r->r_addend = inst;
1547 break;
1548 }
1549 return 0;
1550 }
1551
1552 static void section_rela(const char *modname, struct elf_info *elf,
1553 Elf_Shdr *sechdr)
1554 {
1555 Elf_Sym *sym;
1556 Elf_Rela *rela;
1557 Elf_Rela r;
1558 unsigned int r_sym;
1559 const char *fromsec;
1560
1561 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
1562 Elf_Rela *stop = (void *)start + sechdr->sh_size;
1563
1564 fromsec = sech_name(elf, sechdr);
1565 fromsec += strlen(".rela");
1566 /* if from section (name) is know good then skip it */
1567 if (match(fromsec, section_white_list))
1568 return;
1569
1570 for (rela = start; rela < stop; rela++) {
1571 r.r_offset = TO_NATIVE(rela->r_offset);
1572 #if KERNEL_ELFCLASS == ELFCLASS64
1573 if (elf->hdr->e_machine == EM_MIPS) {
1574 unsigned int r_typ;
1575 r_sym = ELF64_MIPS_R_SYM(rela->r_info);
1576 r_sym = TO_NATIVE(r_sym);
1577 r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
1578 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1579 } else {
1580 r.r_info = TO_NATIVE(rela->r_info);
1581 r_sym = ELF_R_SYM(r.r_info);
1582 }
1583 #else
1584 r.r_info = TO_NATIVE(rela->r_info);
1585 r_sym = ELF_R_SYM(r.r_info);
1586 #endif
1587 r.r_addend = TO_NATIVE(rela->r_addend);
1588 sym = elf->symtab_start + r_sym;
1589 /* Skip special sections */
1590 if (is_shndx_special(sym->st_shndx))
1591 continue;
1592 check_section_mismatch(modname, elf, &r, sym, fromsec);
1593 }
1594 }
1595
1596 static void section_rel(const char *modname, struct elf_info *elf,
1597 Elf_Shdr *sechdr)
1598 {
1599 Elf_Sym *sym;
1600 Elf_Rel *rel;
1601 Elf_Rela r;
1602 unsigned int r_sym;
1603 const char *fromsec;
1604
1605 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
1606 Elf_Rel *stop = (void *)start + sechdr->sh_size;
1607
1608 fromsec = sech_name(elf, sechdr);
1609 fromsec += strlen(".rel");
1610 /* if from section (name) is know good then skip it */
1611 if (match(fromsec, section_white_list))
1612 return;
1613
1614 for (rel = start; rel < stop; rel++) {
1615 r.r_offset = TO_NATIVE(rel->r_offset);
1616 #if KERNEL_ELFCLASS == ELFCLASS64
1617 if (elf->hdr->e_machine == EM_MIPS) {
1618 unsigned int r_typ;
1619 r_sym = ELF64_MIPS_R_SYM(rel->r_info);
1620 r_sym = TO_NATIVE(r_sym);
1621 r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
1622 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1623 } else {
1624 r.r_info = TO_NATIVE(rel->r_info);
1625 r_sym = ELF_R_SYM(r.r_info);
1626 }
1627 #else
1628 r.r_info = TO_NATIVE(rel->r_info);
1629 r_sym = ELF_R_SYM(r.r_info);
1630 #endif
1631 r.r_addend = 0;
1632 switch (elf->hdr->e_machine) {
1633 case EM_386:
1634 if (addend_386_rel(elf, sechdr, &r))
1635 continue;
1636 break;
1637 case EM_ARM:
1638 if (addend_arm_rel(elf, sechdr, &r))
1639 continue;
1640 break;
1641 case EM_MIPS:
1642 if (addend_mips_rel(elf, sechdr, &r))
1643 continue;
1644 break;
1645 }
1646 sym = elf->symtab_start + r_sym;
1647 /* Skip special sections */
1648 if (is_shndx_special(sym->st_shndx))
1649 continue;
1650 check_section_mismatch(modname, elf, &r, sym, fromsec);
1651 }
1652 }
1653
1654 /**
1655 * A module includes a number of sections that are discarded
1656 * either when loaded or when used as built-in.
1657 * For loaded modules all functions marked __init and all data
1658 * marked __initdata will be discarded when the module has been initialized.
1659 * Likewise for modules used built-in the sections marked __exit
1660 * are discarded because __exit marked function are supposed to be called
1661 * only when a module is unloaded which never happens for built-in modules.
1662 * The check_sec_ref() function traverses all relocation records
1663 * to find all references to a section that reference a section that will
1664 * be discarded and warns about it.
1665 **/
1666 static void check_sec_ref(struct module *mod, const char *modname,
1667 struct elf_info *elf)
1668 {
1669 int i;
1670 Elf_Shdr *sechdrs = elf->sechdrs;
1671
1672 /* Walk through all sections */
1673 for (i = 0; i < elf->num_sections; i++) {
1674 check_section(modname, elf, &elf->sechdrs[i]);
1675 /* We want to process only relocation sections and not .init */
1676 if (sechdrs[i].sh_type == SHT_RELA)
1677 section_rela(modname, elf, &elf->sechdrs[i]);
1678 else if (sechdrs[i].sh_type == SHT_REL)
1679 section_rel(modname, elf, &elf->sechdrs[i]);
1680 }
1681 }
1682
1683 static void read_symbols(char *modname)
1684 {
1685 const char *symname;
1686 char *version;
1687 char *license;
1688 struct module *mod;
1689 struct elf_info info = { };
1690 Elf_Sym *sym;
1691
1692 if (!parse_elf(&info, modname))
1693 return;
1694
1695 mod = new_module(modname);
1696
1697 /* When there's no vmlinux, don't print warnings about
1698 * unresolved symbols (since there'll be too many ;) */
1699 if (is_vmlinux(modname)) {
1700 have_vmlinux = 1;
1701 mod->skip = 1;
1702 }
1703
1704 license = get_modinfo(info.modinfo, info.modinfo_len, "license");
1705 if (info.modinfo && !license && !is_vmlinux(modname))
1706 warn("modpost: missing MODULE_LICENSE() in %s\n"
1707 "see include/linux/module.h for "
1708 "more information\n", modname);
1709 while (license) {
1710 if (license_is_gpl_compatible(license))
1711 mod->gpl_compatible = 1;
1712 else {
1713 mod->gpl_compatible = 0;
1714 break;
1715 }
1716 license = get_next_modinfo(info.modinfo, info.modinfo_len,
1717 "license", license);
1718 }
1719
1720 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
1721 symname = info.strtab + sym->st_name;
1722
1723 handle_modversions(mod, &info, sym, symname);
1724 handle_moddevtable(mod, &info, sym, symname);
1725 }
1726 if (!is_vmlinux(modname) ||
1727 (is_vmlinux(modname) && vmlinux_section_warnings))
1728 check_sec_ref(mod, modname, &info);
1729
1730 version = get_modinfo(info.modinfo, info.modinfo_len, "version");
1731 if (version)
1732 maybe_frob_rcs_version(modname, version, info.modinfo,
1733 version - (char *)info.hdr);
1734 if (version || (all_versions && !is_vmlinux(modname)))
1735 get_src_version(modname, mod->srcversion,
1736 sizeof(mod->srcversion)-1);
1737
1738 parse_elf_finish(&info);
1739
1740 /* Our trick to get versioning for module struct etc. - it's
1741 * never passed as an argument to an exported function, so
1742 * the automatic versioning doesn't pick it up, but it's really
1743 * important anyhow */
1744 if (modversions)
1745 mod->unres = alloc_symbol("module_layout", 0, mod->unres);
1746 }
1747
1748 static void read_symbols_from_files(const char *filename)
1749 {
1750 FILE *in = stdin;
1751 char fname[PATH_MAX];
1752
1753 if (strcmp(filename, "-") != 0) {
1754 in = fopen(filename, "r");
1755 if (!in)
1756 fatal("Can't open filenames file %s: %m", filename);
1757 }
1758
1759 while (fgets(fname, PATH_MAX, in) != NULL) {
1760 if (strends(fname, "\n"))
1761 fname[strlen(fname)-1] = '\0';
1762 read_symbols(fname);
1763 }
1764
1765 if (in != stdin)
1766 fclose(in);
1767 }
1768
1769 #define SZ 500
1770
1771 /* We first write the generated file into memory using the
1772 * following helper, then compare to the file on disk and
1773 * only update the later if anything changed */
1774
1775 void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
1776 const char *fmt, ...)
1777 {
1778 char tmp[SZ];
1779 int len;
1780 va_list ap;
1781
1782 va_start(ap, fmt);
1783 len = vsnprintf(tmp, SZ, fmt, ap);
1784 buf_write(buf, tmp, len);
1785 va_end(ap);
1786 }
1787
1788 void buf_write(struct buffer *buf, const char *s, int len)
1789 {
1790 if (buf->size - buf->pos < len) {
1791 buf->size += len + SZ;
1792 buf->p = realloc(buf->p, buf->size);
1793 }
1794 strncpy(buf->p + buf->pos, s, len);
1795 buf->pos += len;
1796 }
1797
1798 static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
1799 {
1800 const char *e = is_vmlinux(m) ?"":".ko";
1801
1802 switch (exp) {
1803 case export_gpl:
1804 fatal("modpost: GPL-incompatible module %s%s "
1805 "uses GPL-only symbol '%s'\n", m, e, s);
1806 break;
1807 case export_unused_gpl:
1808 fatal("modpost: GPL-incompatible module %s%s "
1809 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
1810 break;
1811 case export_gpl_future:
1812 warn("modpost: GPL-incompatible module %s%s "
1813 "uses future GPL-only symbol '%s'\n", m, e, s);
1814 break;
1815 case export_plain:
1816 case export_unused:
1817 case export_unknown:
1818 /* ignore */
1819 break;
1820 }
1821 }
1822
1823 static void check_for_unused(enum export exp, const char *m, const char *s)
1824 {
1825 const char *e = is_vmlinux(m) ?"":".ko";
1826
1827 switch (exp) {
1828 case export_unused:
1829 case export_unused_gpl:
1830 warn("modpost: module %s%s "
1831 "uses symbol '%s' marked UNUSED\n", m, e, s);
1832 break;
1833 default:
1834 /* ignore */
1835 break;
1836 }
1837 }
1838
1839 static void check_exports(struct module *mod)
1840 {
1841 struct symbol *s, *exp;
1842
1843 for (s = mod->unres; s; s = s->next) {
1844 const char *basename;
1845 exp = find_symbol(s->name);
1846 if (!exp || exp->module == mod)
1847 continue;
1848 basename = strrchr(mod->name, '/');
1849 if (basename)
1850 basename++;
1851 else
1852 basename = mod->name;
1853 if (!mod->gpl_compatible)
1854 check_for_gpl_usage(exp->export, basename, exp->name);
1855 check_for_unused(exp->export, basename, exp->name);
1856 }
1857 }
1858
1859 /**
1860 * Header for the generated file
1861 **/
1862 static void add_header(struct buffer *b, struct module *mod)
1863 {
1864 buf_printf(b, "#include <linux/module.h>\n");
1865 buf_printf(b, "#include <linux/vermagic.h>\n");
1866 buf_printf(b, "#include <linux/compiler.h>\n");
1867 buf_printf(b, "\n");
1868 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1869 buf_printf(b, "\n");
1870 buf_printf(b, "__visible struct module __this_module\n");
1871 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
1872 buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
1873 if (mod->has_init)
1874 buf_printf(b, "\t.init = init_module,\n");
1875 if (mod->has_cleanup)
1876 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
1877 "\t.exit = cleanup_module,\n"
1878 "#endif\n");
1879 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
1880 buf_printf(b, "};\n");
1881 }
1882
1883 static void add_intree_flag(struct buffer *b, int is_intree)
1884 {
1885 if (is_intree)
1886 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
1887 }
1888
1889 static void add_staging_flag(struct buffer *b, const char *name)
1890 {
1891 static const char *staging_dir = "drivers/staging";
1892
1893 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0)
1894 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
1895 }
1896
1897 /**
1898 * Record CRCs for unresolved symbols
1899 **/
1900 static int add_versions(struct buffer *b, struct module *mod)
1901 {
1902 struct symbol *s, *exp;
1903 int err = 0;
1904
1905 for (s = mod->unres; s; s = s->next) {
1906 exp = find_symbol(s->name);
1907 if (!exp || exp->module == mod) {
1908 if (have_vmlinux && !s->weak) {
1909 if (warn_unresolved) {
1910 warn("\"%s\" [%s.ko] undefined!\n",
1911 s->name, mod->name);
1912 } else {
1913 merror("\"%s\" [%s.ko] undefined!\n",
1914 s->name, mod->name);
1915 err = 1;
1916 }
1917 }
1918 continue;
1919 }
1920 s->module = exp->module;
1921 s->crc_valid = exp->crc_valid;
1922 s->crc = exp->crc;
1923 }
1924
1925 if (!modversions)
1926 return err;
1927
1928 buf_printf(b, "\n");
1929 buf_printf(b, "static const struct modversion_info ____versions[]\n");
1930 buf_printf(b, "__used\n");
1931 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n");
1932
1933 for (s = mod->unres; s; s = s->next) {
1934 if (!s->module)
1935 continue;
1936 if (!s->crc_valid) {
1937 warn("\"%s\" [%s.ko] has no CRC!\n",
1938 s->name, mod->name);
1939 continue;
1940 }
1941 buf_printf(b, "\t{ %#8x, __VMLINUX_SYMBOL_STR(%s) },\n",
1942 s->crc, s->name);
1943 }
1944
1945 buf_printf(b, "};\n");
1946
1947 return err;
1948 }
1949
1950 static void add_depends(struct buffer *b, struct module *mod,
1951 struct module *modules)
1952 {
1953 struct symbol *s;
1954 struct module *m;
1955 int first = 1;
1956
1957 for (m = modules; m; m = m->next)
1958 m->seen = is_vmlinux(m->name);
1959
1960 buf_printf(b, "\n");
1961 buf_printf(b, "static const char __module_depends[]\n");
1962 buf_printf(b, "__used\n");
1963 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n");
1964 buf_printf(b, "\"depends=");
1965 for (s = mod->unres; s; s = s->next) {
1966 const char *p;
1967 if (!s->module)
1968 continue;
1969
1970 if (s->module->seen)
1971 continue;
1972
1973 s->module->seen = 1;
1974 p = strrchr(s->module->name, '/');
1975 if (p)
1976 p++;
1977 else
1978 p = s->module->name;
1979 buf_printf(b, "%s%s", first ? "" : ",", p);
1980 first = 0;
1981 }
1982 buf_printf(b, "\";\n");
1983 }
1984
1985 static void add_srcversion(struct buffer *b, struct module *mod)
1986 {
1987 if (mod->srcversion[0]) {
1988 buf_printf(b, "\n");
1989 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
1990 mod->srcversion);
1991 }
1992 }
1993
1994 static void write_if_changed(struct buffer *b, const char *fname)
1995 {
1996 char *tmp;
1997 FILE *file;
1998 struct stat st;
1999
2000 file = fopen(fname, "r");
2001 if (!file)
2002 goto write;
2003
2004 if (fstat(fileno(file), &st) < 0)
2005 goto close_write;
2006
2007 if (st.st_size != b->pos)
2008 goto close_write;
2009
2010 tmp = NOFAIL(malloc(b->pos));
2011 if (fread(tmp, 1, b->pos, file) != b->pos)
2012 goto free_write;
2013
2014 if (memcmp(tmp, b->p, b->pos) != 0)
2015 goto free_write;
2016
2017 free(tmp);
2018 fclose(file);
2019 return;
2020
2021 free_write:
2022 free(tmp);
2023 close_write:
2024 fclose(file);
2025 write:
2026 file = fopen(fname, "w");
2027 if (!file) {
2028 perror(fname);
2029 exit(1);
2030 }
2031 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
2032 perror(fname);
2033 exit(1);
2034 }
2035 fclose(file);
2036 }
2037
2038 /* parse Module.symvers file. line format:
2039 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
2040 **/
2041 static void read_dump(const char *fname, unsigned int kernel)
2042 {
2043 unsigned long size, pos = 0;
2044 void *file = grab_file(fname, &size);
2045 char *line;
2046
2047 if (!file)
2048 /* No symbol versions, silently ignore */
2049 return;
2050
2051 while ((line = get_next_line(&pos, file, size))) {
2052 char *symname, *modname, *d, *export, *end;
2053 unsigned int crc;
2054 struct module *mod;
2055 struct symbol *s;
2056
2057 if (!(symname = strchr(line, '\t')))
2058 goto fail;
2059 *symname++ = '\0';
2060 if (!(modname = strchr(symname, '\t')))
2061 goto fail;
2062 *modname++ = '\0';
2063 if ((export = strchr(modname, '\t')) != NULL)
2064 *export++ = '\0';
2065 if (export && ((end = strchr(export, '\t')) != NULL))
2066 *end = '\0';
2067 crc = strtoul(line, &d, 16);
2068 if (*symname == '\0' || *modname == '\0' || *d != '\0')
2069 goto fail;
2070 mod = find_module(modname);
2071 if (!mod) {
2072 if (is_vmlinux(modname))
2073 have_vmlinux = 1;
2074 mod = new_module(modname);
2075 mod->skip = 1;
2076 }
2077 s = sym_add_exported(symname, mod, export_no(export));
2078 s->kernel = kernel;
2079 s->preloaded = 1;
2080 sym_update_crc(symname, mod, crc, export_no(export));
2081 }
2082 return;
2083 fail:
2084 fatal("parse error in symbol dump file\n");
2085 }
2086
2087 /* For normal builds always dump all symbols.
2088 * For external modules only dump symbols
2089 * that are not read from kernel Module.symvers.
2090 **/
2091 static int dump_sym(struct symbol *sym)
2092 {
2093 if (!external_module)
2094 return 1;
2095 if (sym->vmlinux || sym->kernel)
2096 return 0;
2097 return 1;
2098 }
2099
2100 static void write_dump(const char *fname)
2101 {
2102 struct buffer buf = { };
2103 struct symbol *symbol;
2104 int n;
2105
2106 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
2107 symbol = symbolhash[n];
2108 while (symbol) {
2109 if (dump_sym(symbol))
2110 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
2111 symbol->crc, symbol->name,
2112 symbol->module->name,
2113 export_str(symbol->export));
2114 symbol = symbol->next;
2115 }
2116 }
2117 write_if_changed(&buf, fname);
2118 }
2119
2120 struct ext_sym_list {
2121 struct ext_sym_list *next;
2122 const char *file;
2123 };
2124
2125 int main(int argc, char **argv)
2126 {
2127 struct module *mod;
2128 struct buffer buf = { };
2129 char *kernel_read = NULL, *module_read = NULL;
2130 char *dump_write = NULL, *files_source = NULL;
2131 int opt;
2132 int err;
2133 struct ext_sym_list *extsym_iter;
2134 struct ext_sym_list *extsym_start = NULL;
2135
2136 while ((opt = getopt(argc, argv, "i:I:e:mnsST:o:awM:K:")) != -1) {
2137 switch (opt) {
2138 case 'i':
2139 kernel_read = optarg;
2140 break;
2141 case 'I':
2142 module_read = optarg;
2143 external_module = 1;
2144 break;
2145 case 'e':
2146 external_module = 1;
2147 extsym_iter =
2148 NOFAIL(malloc(sizeof(*extsym_iter)));
2149 extsym_iter->next = extsym_start;
2150 extsym_iter->file = optarg;
2151 extsym_start = extsym_iter;
2152 break;
2153 case 'm':
2154 modversions = 1;
2155 break;
2156 case 'n':
2157 ignore_missing_files = 1;
2158 break;
2159 case 'o':
2160 dump_write = optarg;
2161 break;
2162 case 'a':
2163 all_versions = 1;
2164 break;
2165 case 's':
2166 vmlinux_section_warnings = 0;
2167 break;
2168 case 'S':
2169 sec_mismatch_verbose = 0;
2170 break;
2171 case 'T':
2172 files_source = optarg;
2173 break;
2174 case 'w':
2175 warn_unresolved = 1;
2176 break;
2177 default:
2178 exit(1);
2179 }
2180 }
2181
2182 if (kernel_read)
2183 read_dump(kernel_read, 1);
2184 if (module_read)
2185 read_dump(module_read, 0);
2186 while (extsym_start) {
2187 read_dump(extsym_start->file, 0);
2188 extsym_iter = extsym_start->next;
2189 free(extsym_start);
2190 extsym_start = extsym_iter;
2191 }
2192
2193 while (optind < argc)
2194 read_symbols(argv[optind++]);
2195
2196 if (files_source)
2197 read_symbols_from_files(files_source);
2198
2199 for (mod = modules; mod; mod = mod->next) {
2200 if (mod->skip)
2201 continue;
2202 check_exports(mod);
2203 }
2204
2205 err = 0;
2206
2207 for (mod = modules; mod; mod = mod->next) {
2208 char fname[strlen(mod->name) + 10];
2209
2210 if (mod->skip)
2211 continue;
2212
2213 buf.pos = 0;
2214
2215 add_header(&buf, mod);
2216 add_intree_flag(&buf, !external_module);
2217 add_staging_flag(&buf, mod->name);
2218 err |= add_versions(&buf, mod);
2219 add_depends(&buf, mod, modules);
2220 add_moddevtable(&buf, mod);
2221 add_srcversion(&buf, mod);
2222
2223 sprintf(fname, "%s.mod.c", mod->name);
2224 write_if_changed(&buf, fname);
2225 }
2226
2227 if (dump_write)
2228 write_dump(dump_write);
2229 if (sec_mismatch_count && !sec_mismatch_verbose)
2230 warn("modpost: Found %d section mismatch(es).\n"
2231 "To see full details build your kernel with:\n"
2232 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
2233 sec_mismatch_count);
2234
2235 return err;
2236 }
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