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1/* Postprocess module symbol versions
2 *
3 * Copyright 2003 Kai Germaschewski
4 * Copyright 2002-2004 Rusty Russell, IBM Corporation
5 * Copyright 2006-2008 Sam Ravnborg
6 * Based in part on module-init-tools/depmod.c,file2alias
7 *
8 * This software may be used and distributed according to the terms
9 * of the GNU General Public License, incorporated herein by reference.
10 *
11 * Usage: modpost vmlinux module1.o module2.o ...
12 */
13
14#define _GNU_SOURCE
15#include <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/linux/license.h"
23
24/* Are we using CONFIG_MODVERSIONS? */
25static int modversions = 0;
26/* Warn about undefined symbols? (do so if we have vmlinux) */
27static int have_vmlinux = 0;
28/* Is CONFIG_MODULE_SRCVERSION_ALL set? */
29static int all_versions = 0;
30/* If we are modposting external module set to 1 */
31static int external_module = 0;
32/* Warn about section mismatch in vmlinux if set to 1 */
33static int vmlinux_section_warnings = 1;
34/* Only warn about unresolved symbols */
35static int warn_unresolved = 0;
36/* How a symbol is exported */
37static int sec_mismatch_count = 0;
38static int sec_mismatch_fatal = 0;
39/* ignore missing files */
40static int ignore_missing_files;
41/* write namespace dependencies */
42static int write_namespace_deps;
43
44enum export {
45 export_plain, export_unused, export_gpl,
46 export_unused_gpl, export_gpl_future, export_unknown
47};
48
49/* In kernel, this size is defined in linux/module.h;
50 * here we use Elf_Addr instead of long for covering cross-compile
51 */
52
53#define MODULE_NAME_LEN (64 - sizeof(Elf_Addr))
54
55#define PRINTF __attribute__ ((format (printf, 1, 2)))
56
57PRINTF void fatal(const char *fmt, ...)
58{
59 va_list arglist;
60
61 fprintf(stderr, "FATAL: ");
62
63 va_start(arglist, fmt);
64 vfprintf(stderr, fmt, arglist);
65 va_end(arglist);
66
67 exit(1);
68}
69
70PRINTF void warn(const char *fmt, ...)
71{
72 va_list arglist;
73
74 fprintf(stderr, "WARNING: ");
75
76 va_start(arglist, fmt);
77 vfprintf(stderr, fmt, arglist);
78 va_end(arglist);
79}
80
81PRINTF void merror(const char *fmt, ...)
82{
83 va_list arglist;
84
85 fprintf(stderr, "ERROR: ");
86
87 va_start(arglist, fmt);
88 vfprintf(stderr, fmt, arglist);
89 va_end(arglist);
90}
91
92static inline bool strends(const char *str, const char *postfix)
93{
94 if (strlen(str) < strlen(postfix))
95 return false;
96
97 return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0;
98}
99
100static int is_vmlinux(const char *modname)
101{
102 const char *myname;
103
104 myname = strrchr(modname, '/');
105 if (myname)
106 myname++;
107 else
108 myname = modname;
109
110 return (strcmp(myname, "vmlinux") == 0) ||
111 (strcmp(myname, "vmlinux.o") == 0);
112}
113
114void *do_nofail(void *ptr, const char *expr)
115{
116 if (!ptr)
117 fatal("modpost: Memory allocation failure: %s.\n", expr);
118
119 return ptr;
120}
121
122/* A list of all modules we processed */
123static struct module *modules;
124
125static struct module *find_module(const char *modname)
126{
127 struct module *mod;
128
129 for (mod = modules; mod; mod = mod->next)
130 if (strcmp(mod->name, modname) == 0)
131 break;
132 return mod;
133}
134
135static struct module *new_module(const char *modname)
136{
137 struct module *mod;
138 char *p;
139
140 mod = NOFAIL(malloc(sizeof(*mod)));
141 memset(mod, 0, sizeof(*mod));
142 p = NOFAIL(strdup(modname));
143
144 /* strip trailing .o */
145 if (strends(p, ".o")) {
146 p[strlen(p) - 2] = '\0';
147 mod->is_dot_o = 1;
148 }
149
150 /* add to list */
151 mod->name = p;
152 mod->gpl_compatible = -1;
153 mod->next = modules;
154 modules = mod;
155
156 return mod;
157}
158
159/* A hash of all exported symbols,
160 * struct symbol is also used for lists of unresolved symbols */
161
162#define SYMBOL_HASH_SIZE 1024
163
164struct symbol {
165 struct symbol *next;
166 struct module *module;
167 unsigned int crc;
168 int crc_valid;
169 char *namespace;
170 unsigned int weak:1;
171 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */
172 unsigned int kernel:1; /* 1 if symbol is from kernel
173 * (only for external modules) **/
174 unsigned int preloaded:1; /* 1 if symbol from Module.symvers, or crc */
175 unsigned int is_static:1; /* 1 if symbol is not global */
176 enum export export; /* Type of export */
177 char name[0];
178};
179
180static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
181
182/* This is based on the hash agorithm from gdbm, via tdb */
183static inline unsigned int tdb_hash(const char *name)
184{
185 unsigned value; /* Used to compute the hash value. */
186 unsigned i; /* Used to cycle through random values. */
187
188 /* Set the initial value from the key size. */
189 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++)
190 value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
191
192 return (1103515243 * value + 12345);
193}
194
195/**
196 * Allocate a new symbols for use in the hash of exported symbols or
197 * the list of unresolved symbols per module
198 **/
199static struct symbol *alloc_symbol(const char *name, unsigned int weak,
200 struct symbol *next)
201{
202 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
203
204 memset(s, 0, sizeof(*s));
205 strcpy(s->name, name);
206 s->weak = weak;
207 s->next = next;
208 s->is_static = 1;
209 return s;
210}
211
212/* For the hash of exported symbols */
213static struct symbol *new_symbol(const char *name, struct module *module,
214 enum export export)
215{
216 unsigned int hash;
217 struct symbol *new;
218
219 hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
220 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
221 new->module = module;
222 new->export = export;
223 return new;
224}
225
226static struct symbol *find_symbol(const char *name)
227{
228 struct symbol *s;
229
230 /* For our purposes, .foo matches foo. PPC64 needs this. */
231 if (name[0] == '.')
232 name++;
233
234 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
235 if (strcmp(s->name, name) == 0)
236 return s;
237 }
238 return NULL;
239}
240
241static bool contains_namespace(struct namespace_list *list,
242 const char *namespace)
243{
244 struct namespace_list *ns_entry;
245
246 for (ns_entry = list; ns_entry != NULL; ns_entry = ns_entry->next)
247 if (strcmp(ns_entry->namespace, namespace) == 0)
248 return true;
249
250 return false;
251}
252
253static void add_namespace(struct namespace_list **list, const char *namespace)
254{
255 struct namespace_list *ns_entry;
256
257 if (!contains_namespace(*list, namespace)) {
258 ns_entry = NOFAIL(malloc(sizeof(struct namespace_list) +
259 strlen(namespace) + 1));
260 strcpy(ns_entry->namespace, namespace);
261 ns_entry->next = *list;
262 *list = ns_entry;
263 }
264}
265
266static bool module_imports_namespace(struct module *module,
267 const char *namespace)
268{
269 return contains_namespace(module->imported_namespaces, namespace);
270}
271
272static const struct {
273 const char *str;
274 enum export export;
275} export_list[] = {
276 { .str = "EXPORT_SYMBOL", .export = export_plain },
277 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
278 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
279 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
280 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
281 { .str = "(unknown)", .export = export_unknown },
282};
283
284
285static const char *export_str(enum export ex)
286{
287 return export_list[ex].str;
288}
289
290static enum export export_no(const char *s)
291{
292 int i;
293
294 if (!s)
295 return export_unknown;
296 for (i = 0; export_list[i].export != export_unknown; i++) {
297 if (strcmp(export_list[i].str, s) == 0)
298 return export_list[i].export;
299 }
300 return export_unknown;
301}
302
303static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr)
304{
305 return (void *)elf->hdr +
306 elf->sechdrs[elf->secindex_strings].sh_offset +
307 sechdr->sh_name;
308}
309
310static const char *sec_name(struct elf_info *elf, int secindex)
311{
312 return sech_name(elf, &elf->sechdrs[secindex]);
313}
314
315#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
316
317static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
318{
319 const char *secname = sec_name(elf, sec);
320
321 if (strstarts(secname, "___ksymtab+"))
322 return export_plain;
323 else if (strstarts(secname, "___ksymtab_unused+"))
324 return export_unused;
325 else if (strstarts(secname, "___ksymtab_gpl+"))
326 return export_gpl;
327 else if (strstarts(secname, "___ksymtab_unused_gpl+"))
328 return export_unused_gpl;
329 else if (strstarts(secname, "___ksymtab_gpl_future+"))
330 return export_gpl_future;
331 else
332 return export_unknown;
333}
334
335static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
336{
337 if (sec == elf->export_sec)
338 return export_plain;
339 else if (sec == elf->export_unused_sec)
340 return export_unused;
341 else if (sec == elf->export_gpl_sec)
342 return export_gpl;
343 else if (sec == elf->export_unused_gpl_sec)
344 return export_unused_gpl;
345 else if (sec == elf->export_gpl_future_sec)
346 return export_gpl_future;
347 else
348 return export_unknown;
349}
350
351static const char *namespace_from_kstrtabns(struct elf_info *info,
352 Elf_Sym *kstrtabns)
353{
354 char *value = info->ksymtab_strings + kstrtabns->st_value;
355 return value[0] ? value : NULL;
356}
357
358static void sym_update_namespace(const char *symname, const char *namespace)
359{
360 struct symbol *s = find_symbol(symname);
361
362 /*
363 * That symbol should have been created earlier and thus this is
364 * actually an assertion.
365 */
366 if (!s) {
367 merror("Could not update namespace(%s) for symbol %s\n",
368 namespace, symname);
369 return;
370 }
371
372 free(s->namespace);
373 s->namespace =
374 namespace && namespace[0] ? NOFAIL(strdup(namespace)) : NULL;
375}
376
377/**
378 * Add an exported symbol - it may have already been added without a
379 * CRC, in this case just update the CRC
380 **/
381static struct symbol *sym_add_exported(const char *name, struct module *mod,
382 enum export export)
383{
384 struct symbol *s = find_symbol(name);
385
386 if (!s) {
387 s = new_symbol(name, mod, export);
388 } else {
389 if (!s->preloaded) {
390 warn("%s: '%s' exported twice. Previous export was in %s%s\n",
391 mod->name, name, s->module->name,
392 is_vmlinux(s->module->name) ? "" : ".ko");
393 } else {
394 /* In case Module.symvers was out of date */
395 s->module = mod;
396 }
397 }
398 s->preloaded = 0;
399 s->vmlinux = is_vmlinux(mod->name);
400 s->kernel = 0;
401 s->export = export;
402 return s;
403}
404
405static void sym_update_crc(const char *name, struct module *mod,
406 unsigned int crc, enum export export)
407{
408 struct symbol *s = find_symbol(name);
409
410 if (!s) {
411 s = new_symbol(name, mod, export);
412 /* Don't complain when we find it later. */
413 s->preloaded = 1;
414 }
415 s->crc = crc;
416 s->crc_valid = 1;
417}
418
419void *grab_file(const char *filename, unsigned long *size)
420{
421 struct stat st;
422 void *map = MAP_FAILED;
423 int fd;
424
425 fd = open(filename, O_RDONLY);
426 if (fd < 0)
427 return NULL;
428 if (fstat(fd, &st))
429 goto failed;
430
431 *size = st.st_size;
432 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
433
434failed:
435 close(fd);
436 if (map == MAP_FAILED)
437 return NULL;
438 return map;
439}
440
441/**
442 * Return a copy of the next line in a mmap'ed file.
443 * spaces in the beginning of the line is trimmed away.
444 * Return a pointer to a static buffer.
445 **/
446char *get_next_line(unsigned long *pos, void *file, unsigned long size)
447{
448 static char line[4096];
449 int skip = 1;
450 size_t len = 0;
451 signed char *p = (signed char *)file + *pos;
452 char *s = line;
453
454 for (; *pos < size ; (*pos)++) {
455 if (skip && isspace(*p)) {
456 p++;
457 continue;
458 }
459 skip = 0;
460 if (*p != '\n' && (*pos < size)) {
461 len++;
462 *s++ = *p++;
463 if (len > 4095)
464 break; /* Too long, stop */
465 } else {
466 /* End of string */
467 *s = '\0';
468 return line;
469 }
470 }
471 /* End of buffer */
472 return NULL;
473}
474
475void release_file(void *file, unsigned long size)
476{
477 munmap(file, size);
478}
479
480static int parse_elf(struct elf_info *info, const char *filename)
481{
482 unsigned int i;
483 Elf_Ehdr *hdr;
484 Elf_Shdr *sechdrs;
485 Elf_Sym *sym;
486 const char *secstrings;
487 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
488
489 hdr = grab_file(filename, &info->size);
490 if (!hdr) {
491 if (ignore_missing_files) {
492 fprintf(stderr, "%s: %s (ignored)\n", filename,
493 strerror(errno));
494 return 0;
495 }
496 perror(filename);
497 exit(1);
498 }
499 info->hdr = hdr;
500 if (info->size < sizeof(*hdr)) {
501 /* file too small, assume this is an empty .o file */
502 return 0;
503 }
504 /* Is this a valid ELF file? */
505 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
506 (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
507 (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
508 (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
509 /* Not an ELF file - silently ignore it */
510 return 0;
511 }
512 /* Fix endianness in ELF header */
513 hdr->e_type = TO_NATIVE(hdr->e_type);
514 hdr->e_machine = TO_NATIVE(hdr->e_machine);
515 hdr->e_version = TO_NATIVE(hdr->e_version);
516 hdr->e_entry = TO_NATIVE(hdr->e_entry);
517 hdr->e_phoff = TO_NATIVE(hdr->e_phoff);
518 hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
519 hdr->e_flags = TO_NATIVE(hdr->e_flags);
520 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize);
521 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
522 hdr->e_phnum = TO_NATIVE(hdr->e_phnum);
523 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
524 hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
525 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
526 sechdrs = (void *)hdr + hdr->e_shoff;
527 info->sechdrs = sechdrs;
528
529 /* Check if file offset is correct */
530 if (hdr->e_shoff > info->size) {
531 fatal("section header offset=%lu in file '%s' is bigger than "
532 "filesize=%lu\n", (unsigned long)hdr->e_shoff,
533 filename, info->size);
534 return 0;
535 }
536
537 if (hdr->e_shnum == SHN_UNDEF) {
538 /*
539 * There are more than 64k sections,
540 * read count from .sh_size.
541 */
542 info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
543 }
544 else {
545 info->num_sections = hdr->e_shnum;
546 }
547 if (hdr->e_shstrndx == SHN_XINDEX) {
548 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
549 }
550 else {
551 info->secindex_strings = hdr->e_shstrndx;
552 }
553
554 /* Fix endianness in section headers */
555 for (i = 0; i < info->num_sections; i++) {
556 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
557 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
558 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
559 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
560 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
561 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
562 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
563 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
564 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
565 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
566 }
567 /* Find symbol table. */
568 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
569 for (i = 1; i < info->num_sections; i++) {
570 const char *secname;
571 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
572
573 if (!nobits && sechdrs[i].sh_offset > info->size) {
574 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
575 "sizeof(*hrd)=%zu\n", filename,
576 (unsigned long)sechdrs[i].sh_offset,
577 sizeof(*hdr));
578 return 0;
579 }
580 secname = secstrings + sechdrs[i].sh_name;
581 if (strcmp(secname, ".modinfo") == 0) {
582 if (nobits)
583 fatal("%s has NOBITS .modinfo\n", filename);
584 info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
585 info->modinfo_len = sechdrs[i].sh_size;
586 } else if (strcmp(secname, "__ksymtab") == 0)
587 info->export_sec = i;
588 else if (strcmp(secname, "__ksymtab_unused") == 0)
589 info->export_unused_sec = i;
590 else if (strcmp(secname, "__ksymtab_gpl") == 0)
591 info->export_gpl_sec = i;
592 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
593 info->export_unused_gpl_sec = i;
594 else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
595 info->export_gpl_future_sec = i;
596 else if (strcmp(secname, "__ksymtab_strings") == 0)
597 info->ksymtab_strings = (void *)hdr +
598 sechdrs[i].sh_offset -
599 sechdrs[i].sh_addr;
600
601 if (sechdrs[i].sh_type == SHT_SYMTAB) {
602 unsigned int sh_link_idx;
603 symtab_idx = i;
604 info->symtab_start = (void *)hdr +
605 sechdrs[i].sh_offset;
606 info->symtab_stop = (void *)hdr +
607 sechdrs[i].sh_offset + sechdrs[i].sh_size;
608 sh_link_idx = sechdrs[i].sh_link;
609 info->strtab = (void *)hdr +
610 sechdrs[sh_link_idx].sh_offset;
611 }
612
613 /* 32bit section no. table? ("more than 64k sections") */
614 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
615 symtab_shndx_idx = i;
616 info->symtab_shndx_start = (void *)hdr +
617 sechdrs[i].sh_offset;
618 info->symtab_shndx_stop = (void *)hdr +
619 sechdrs[i].sh_offset + sechdrs[i].sh_size;
620 }
621 }
622 if (!info->symtab_start)
623 fatal("%s has no symtab?\n", filename);
624
625 /* Fix endianness in symbols */
626 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
627 sym->st_shndx = TO_NATIVE(sym->st_shndx);
628 sym->st_name = TO_NATIVE(sym->st_name);
629 sym->st_value = TO_NATIVE(sym->st_value);
630 sym->st_size = TO_NATIVE(sym->st_size);
631 }
632
633 if (symtab_shndx_idx != ~0U) {
634 Elf32_Word *p;
635 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
636 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
637 filename, sechdrs[symtab_shndx_idx].sh_link,
638 symtab_idx);
639 /* Fix endianness */
640 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
641 p++)
642 *p = TO_NATIVE(*p);
643 }
644
645 return 1;
646}
647
648static void parse_elf_finish(struct elf_info *info)
649{
650 release_file(info->hdr, info->size);
651}
652
653static int ignore_undef_symbol(struct elf_info *info, const char *symname)
654{
655 /* ignore __this_module, it will be resolved shortly */
656 if (strcmp(symname, "__this_module") == 0)
657 return 1;
658 /* ignore global offset table */
659 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
660 return 1;
661 if (info->hdr->e_machine == EM_PPC)
662 /* Special register function linked on all modules during final link of .ko */
663 if (strstarts(symname, "_restgpr_") ||
664 strstarts(symname, "_savegpr_") ||
665 strstarts(symname, "_rest32gpr_") ||
666 strstarts(symname, "_save32gpr_") ||
667 strstarts(symname, "_restvr_") ||
668 strstarts(symname, "_savevr_"))
669 return 1;
670 if (info->hdr->e_machine == EM_PPC64)
671 /* Special register function linked on all modules during final link of .ko */
672 if (strstarts(symname, "_restgpr0_") ||
673 strstarts(symname, "_savegpr0_") ||
674 strstarts(symname, "_restvr_") ||
675 strstarts(symname, "_savevr_") ||
676 strcmp(symname, ".TOC.") == 0)
677 return 1;
678 /* Do not ignore this symbol */
679 return 0;
680}
681
682static void handle_modversions(struct module *mod, struct elf_info *info,
683 Elf_Sym *sym, const char *symname)
684{
685 unsigned int crc;
686 enum export export;
687 bool is_crc = false;
688 const char *name;
689
690 if ((!is_vmlinux(mod->name) || mod->is_dot_o) &&
691 strstarts(symname, "__ksymtab"))
692 export = export_from_secname(info, get_secindex(info, sym));
693 else
694 export = export_from_sec(info, get_secindex(info, sym));
695
696 /* CRC'd symbol */
697 if (strstarts(symname, "__crc_")) {
698 is_crc = true;
699 crc = (unsigned int) sym->st_value;
700 if (sym->st_shndx != SHN_UNDEF && sym->st_shndx != SHN_ABS) {
701 unsigned int *crcp;
702
703 /* symbol points to the CRC in the ELF object */
704 crcp = (void *)info->hdr + sym->st_value +
705 info->sechdrs[sym->st_shndx].sh_offset -
706 (info->hdr->e_type != ET_REL ?
707 info->sechdrs[sym->st_shndx].sh_addr : 0);
708 crc = TO_NATIVE(*crcp);
709 }
710 sym_update_crc(symname + strlen("__crc_"), mod, crc,
711 export);
712 }
713
714 switch (sym->st_shndx) {
715 case SHN_COMMON:
716 if (strstarts(symname, "__gnu_lto_")) {
717 /* Should warn here, but modpost runs before the linker */
718 } else
719 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
720 break;
721 case SHN_UNDEF:
722 /* undefined symbol */
723 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
724 ELF_ST_BIND(sym->st_info) != STB_WEAK)
725 break;
726 if (ignore_undef_symbol(info, symname))
727 break;
728/* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
729#if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
730/* add compatibility with older glibc */
731#ifndef STT_SPARC_REGISTER
732#define STT_SPARC_REGISTER STT_REGISTER
733#endif
734 if (info->hdr->e_machine == EM_SPARC ||
735 info->hdr->e_machine == EM_SPARCV9) {
736 /* Ignore register directives. */
737 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
738 break;
739 if (symname[0] == '.') {
740 char *munged = NOFAIL(strdup(symname));
741 munged[0] = '_';
742 munged[1] = toupper(munged[1]);
743 symname = munged;
744 }
745 }
746#endif
747
748 if (is_crc) {
749 const char *e = is_vmlinux(mod->name) ?"":".ko";
750 warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n",
751 symname + strlen("__crc_"), mod->name, e);
752 }
753 mod->unres = alloc_symbol(symname,
754 ELF_ST_BIND(sym->st_info) == STB_WEAK,
755 mod->unres);
756 break;
757 default:
758 /* All exported symbols */
759 if (strstarts(symname, "__ksymtab_")) {
760 name = symname + strlen("__ksymtab_");
761 sym_add_exported(name, mod, export);
762 }
763 if (strcmp(symname, "init_module") == 0)
764 mod->has_init = 1;
765 if (strcmp(symname, "cleanup_module") == 0)
766 mod->has_cleanup = 1;
767 break;
768 }
769}
770
771/**
772 * Parse tag=value strings from .modinfo section
773 **/
774static char *next_string(char *string, unsigned long *secsize)
775{
776 /* Skip non-zero chars */
777 while (string[0]) {
778 string++;
779 if ((*secsize)-- <= 1)
780 return NULL;
781 }
782
783 /* Skip any zero padding. */
784 while (!string[0]) {
785 string++;
786 if ((*secsize)-- <= 1)
787 return NULL;
788 }
789 return string;
790}
791
792static char *get_next_modinfo(struct elf_info *info, const char *tag,
793 char *prev)
794{
795 char *p;
796 unsigned int taglen = strlen(tag);
797 char *modinfo = info->modinfo;
798 unsigned long size = info->modinfo_len;
799
800 if (prev) {
801 size -= prev - modinfo;
802 modinfo = next_string(prev, &size);
803 }
804
805 for (p = modinfo; p; p = next_string(p, &size)) {
806 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
807 return p + taglen + 1;
808 }
809 return NULL;
810}
811
812static char *get_modinfo(struct elf_info *info, const char *tag)
813
814{
815 return get_next_modinfo(info, tag, NULL);
816}
817
818/**
819 * Test if string s ends in string sub
820 * return 0 if match
821 **/
822static int strrcmp(const char *s, const char *sub)
823{
824 int slen, sublen;
825
826 if (!s || !sub)
827 return 1;
828
829 slen = strlen(s);
830 sublen = strlen(sub);
831
832 if ((slen == 0) || (sublen == 0))
833 return 1;
834
835 if (sublen > slen)
836 return 1;
837
838 return memcmp(s + slen - sublen, sub, sublen);
839}
840
841static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
842{
843 if (sym)
844 return elf->strtab + sym->st_name;
845 else
846 return "(unknown)";
847}
848
849/* The pattern is an array of simple patterns.
850 * "foo" will match an exact string equal to "foo"
851 * "*foo" will match a string that ends with "foo"
852 * "foo*" will match a string that begins with "foo"
853 * "*foo*" will match a string that contains "foo"
854 */
855static int match(const char *sym, const char * const pat[])
856{
857 const char *p;
858 while (*pat) {
859 p = *pat++;
860 const char *endp = p + strlen(p) - 1;
861
862 /* "*foo*" */
863 if (*p == '*' && *endp == '*') {
864 char *bare = NOFAIL(strndup(p + 1, strlen(p) - 2));
865 char *here = strstr(sym, bare);
866
867 free(bare);
868 if (here != NULL)
869 return 1;
870 }
871 /* "*foo" */
872 else if (*p == '*') {
873 if (strrcmp(sym, p + 1) == 0)
874 return 1;
875 }
876 /* "foo*" */
877 else if (*endp == '*') {
878 if (strncmp(sym, p, strlen(p) - 1) == 0)
879 return 1;
880 }
881 /* no wildcards */
882 else {
883 if (strcmp(p, sym) == 0)
884 return 1;
885 }
886 }
887 /* no match */
888 return 0;
889}
890
891/* sections that we do not want to do full section mismatch check on */
892static const char *const section_white_list[] =
893{
894 ".comment*",
895 ".debug*",
896 ".cranges", /* sh64 */
897 ".zdebug*", /* Compressed debug sections. */
898 ".GCC.command.line", /* record-gcc-switches */
899 ".mdebug*", /* alpha, score, mips etc. */
900 ".pdr", /* alpha, score, mips etc. */
901 ".stab*",
902 ".note*",
903 ".got*",
904 ".toc*",
905 ".xt.prop", /* xtensa */
906 ".xt.lit", /* xtensa */
907 ".arcextmap*", /* arc */
908 ".gnu.linkonce.arcext*", /* arc : modules */
909 ".cmem*", /* EZchip */
910 ".fmt_slot*", /* EZchip */
911 ".gnu.lto*",
912 ".discard.*",
913 NULL
914};
915
916/*
917 * This is used to find sections missing the SHF_ALLOC flag.
918 * The cause of this is often a section specified in assembler
919 * without "ax" / "aw".
920 */
921static void check_section(const char *modname, struct elf_info *elf,
922 Elf_Shdr *sechdr)
923{
924 const char *sec = sech_name(elf, sechdr);
925
926 if (sechdr->sh_type == SHT_PROGBITS &&
927 !(sechdr->sh_flags & SHF_ALLOC) &&
928 !match(sec, section_white_list)) {
929 warn("%s (%s): unexpected non-allocatable section.\n"
930 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
931 "Note that for example <linux/init.h> contains\n"
932 "section definitions for use in .S files.\n\n",
933 modname, sec);
934 }
935}
936
937
938
939#define ALL_INIT_DATA_SECTIONS \
940 ".init.setup", ".init.rodata", ".meminit.rodata", \
941 ".init.data", ".meminit.data"
942#define ALL_EXIT_DATA_SECTIONS \
943 ".exit.data", ".memexit.data"
944
945#define ALL_INIT_TEXT_SECTIONS \
946 ".init.text", ".meminit.text"
947#define ALL_EXIT_TEXT_SECTIONS \
948 ".exit.text", ".memexit.text"
949
950#define ALL_PCI_INIT_SECTIONS \
951 ".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \
952 ".pci_fixup_enable", ".pci_fixup_resume", \
953 ".pci_fixup_resume_early", ".pci_fixup_suspend"
954
955#define ALL_XXXINIT_SECTIONS MEM_INIT_SECTIONS
956#define ALL_XXXEXIT_SECTIONS MEM_EXIT_SECTIONS
957
958#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
959#define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
960
961#define DATA_SECTIONS ".data", ".data.rel"
962#define TEXT_SECTIONS ".text", ".text.unlikely", ".sched.text", \
963 ".kprobes.text", ".cpuidle.text"
964#define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \
965 ".fixup", ".entry.text", ".exception.text", ".text.*", \
966 ".coldtext"
967
968#define INIT_SECTIONS ".init.*"
969#define MEM_INIT_SECTIONS ".meminit.*"
970
971#define EXIT_SECTIONS ".exit.*"
972#define MEM_EXIT_SECTIONS ".memexit.*"
973
974#define ALL_TEXT_SECTIONS ALL_INIT_TEXT_SECTIONS, ALL_EXIT_TEXT_SECTIONS, \
975 TEXT_SECTIONS, OTHER_TEXT_SECTIONS
976
977/* init data sections */
978static const char *const init_data_sections[] =
979 { ALL_INIT_DATA_SECTIONS, NULL };
980
981/* all init sections */
982static const char *const init_sections[] = { ALL_INIT_SECTIONS, NULL };
983
984/* All init and exit sections (code + data) */
985static const char *const init_exit_sections[] =
986 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
987
988/* all text sections */
989static const char *const text_sections[] = { ALL_TEXT_SECTIONS, NULL };
990
991/* data section */
992static const char *const data_sections[] = { DATA_SECTIONS, NULL };
993
994
995/* symbols in .data that may refer to init/exit sections */
996#define DEFAULT_SYMBOL_WHITE_LIST \
997 "*driver", \
998 "*_template", /* scsi uses *_template a lot */ \
999 "*_timer", /* arm uses ops structures named _timer a lot */ \
1000 "*_sht", /* scsi also used *_sht to some extent */ \
1001 "*_ops", \
1002 "*_probe", \
1003 "*_probe_one", \
1004 "*_console"
1005
1006static const char *const head_sections[] = { ".head.text*", NULL };
1007static const char *const linker_symbols[] =
1008 { "__init_begin", "_sinittext", "_einittext", NULL };
1009static const char *const optim_symbols[] = { "*.constprop.*", NULL };
1010
1011enum mismatch {
1012 TEXT_TO_ANY_INIT,
1013 DATA_TO_ANY_INIT,
1014 TEXT_TO_ANY_EXIT,
1015 DATA_TO_ANY_EXIT,
1016 XXXINIT_TO_SOME_INIT,
1017 XXXEXIT_TO_SOME_EXIT,
1018 ANY_INIT_TO_ANY_EXIT,
1019 ANY_EXIT_TO_ANY_INIT,
1020 EXPORT_TO_INIT_EXIT,
1021 EXTABLE_TO_NON_TEXT,
1022};
1023
1024/**
1025 * Describe how to match sections on different criterias:
1026 *
1027 * @fromsec: Array of sections to be matched.
1028 *
1029 * @bad_tosec: Relocations applied to a section in @fromsec to a section in
1030 * this array is forbidden (black-list). Can be empty.
1031 *
1032 * @good_tosec: Relocations applied to a section in @fromsec must be
1033 * targetting sections in this array (white-list). Can be empty.
1034 *
1035 * @mismatch: Type of mismatch.
1036 *
1037 * @symbol_white_list: Do not match a relocation to a symbol in this list
1038 * even if it is targetting a section in @bad_to_sec.
1039 *
1040 * @handler: Specific handler to call when a match is found. If NULL,
1041 * default_mismatch_handler() will be called.
1042 *
1043 */
1044struct sectioncheck {
1045 const char *fromsec[20];
1046 const char *bad_tosec[20];
1047 const char *good_tosec[20];
1048 enum mismatch mismatch;
1049 const char *symbol_white_list[20];
1050 void (*handler)(const char *modname, struct elf_info *elf,
1051 const struct sectioncheck* const mismatch,
1052 Elf_Rela *r, Elf_Sym *sym, const char *fromsec);
1053
1054};
1055
1056static void extable_mismatch_handler(const char *modname, struct elf_info *elf,
1057 const struct sectioncheck* const mismatch,
1058 Elf_Rela *r, Elf_Sym *sym,
1059 const char *fromsec);
1060
1061static const struct sectioncheck sectioncheck[] = {
1062/* Do not reference init/exit code/data from
1063 * normal code and data
1064 */
1065{
1066 .fromsec = { TEXT_SECTIONS, NULL },
1067 .bad_tosec = { ALL_INIT_SECTIONS, NULL },
1068 .mismatch = TEXT_TO_ANY_INIT,
1069 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1070},
1071{
1072 .fromsec = { DATA_SECTIONS, NULL },
1073 .bad_tosec = { ALL_XXXINIT_SECTIONS, NULL },
1074 .mismatch = DATA_TO_ANY_INIT,
1075 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1076},
1077{
1078 .fromsec = { DATA_SECTIONS, NULL },
1079 .bad_tosec = { INIT_SECTIONS, NULL },
1080 .mismatch = DATA_TO_ANY_INIT,
1081 .symbol_white_list = {
1082 "*_template", "*_timer", "*_sht", "*_ops",
1083 "*_probe", "*_probe_one", "*_console", NULL
1084 },
1085},
1086{
1087 .fromsec = { TEXT_SECTIONS, NULL },
1088 .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
1089 .mismatch = TEXT_TO_ANY_EXIT,
1090 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1091},
1092{
1093 .fromsec = { DATA_SECTIONS, NULL },
1094 .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
1095 .mismatch = DATA_TO_ANY_EXIT,
1096 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1097},
1098/* Do not reference init code/data from meminit code/data */
1099{
1100 .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
1101 .bad_tosec = { INIT_SECTIONS, NULL },
1102 .mismatch = XXXINIT_TO_SOME_INIT,
1103 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1104},
1105/* Do not reference exit code/data from memexit code/data */
1106{
1107 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
1108 .bad_tosec = { EXIT_SECTIONS, NULL },
1109 .mismatch = XXXEXIT_TO_SOME_EXIT,
1110 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1111},
1112/* Do not use exit code/data from init code */
1113{
1114 .fromsec = { ALL_INIT_SECTIONS, NULL },
1115 .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
1116 .mismatch = ANY_INIT_TO_ANY_EXIT,
1117 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1118},
1119/* Do not use init code/data from exit code */
1120{
1121 .fromsec = { ALL_EXIT_SECTIONS, NULL },
1122 .bad_tosec = { ALL_INIT_SECTIONS, NULL },
1123 .mismatch = ANY_EXIT_TO_ANY_INIT,
1124 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1125},
1126{
1127 .fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
1128 .bad_tosec = { INIT_SECTIONS, NULL },
1129 .mismatch = ANY_INIT_TO_ANY_EXIT,
1130 .symbol_white_list = { NULL },
1131},
1132/* Do not export init/exit functions or data */
1133{
1134 .fromsec = { "__ksymtab*", NULL },
1135 .bad_tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
1136 .mismatch = EXPORT_TO_INIT_EXIT,
1137 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1138},
1139{
1140 .fromsec = { "__ex_table", NULL },
1141 /* If you're adding any new black-listed sections in here, consider
1142 * adding a special 'printer' for them in scripts/check_extable.
1143 */
1144 .bad_tosec = { ".altinstr_replacement", NULL },
1145 .good_tosec = {ALL_TEXT_SECTIONS , NULL},
1146 .mismatch = EXTABLE_TO_NON_TEXT,
1147 .handler = extable_mismatch_handler,
1148}
1149};
1150
1151static const struct sectioncheck *section_mismatch(
1152 const char *fromsec, const char *tosec)
1153{
1154 int i;
1155 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
1156 const struct sectioncheck *check = §ioncheck[0];
1157
1158 /*
1159 * The target section could be the SHT_NUL section when we're
1160 * handling relocations to un-resolved symbols, trying to match it
1161 * doesn't make much sense and causes build failures on parisc
1162 * architectures.
1163 */
1164 if (*tosec == '\0')
1165 return NULL;
1166
1167 for (i = 0; i < elems; i++) {
1168 if (match(fromsec, check->fromsec)) {
1169 if (check->bad_tosec[0] && match(tosec, check->bad_tosec))
1170 return check;
1171 if (check->good_tosec[0] && !match(tosec, check->good_tosec))
1172 return check;
1173 }
1174 check++;
1175 }
1176 return NULL;
1177}
1178
1179/**
1180 * Whitelist to allow certain references to pass with no warning.
1181 *
1182 * Pattern 1:
1183 * If a module parameter is declared __initdata and permissions=0
1184 * then this is legal despite the warning generated.
1185 * We cannot see value of permissions here, so just ignore
1186 * this pattern.
1187 * The pattern is identified by:
1188 * tosec = .init.data
1189 * fromsec = .data*
1190 * atsym =__param*
1191 *
1192 * Pattern 1a:
1193 * module_param_call() ops can refer to __init set function if permissions=0
1194 * The pattern is identified by:
1195 * tosec = .init.text
1196 * fromsec = .data*
1197 * atsym = __param_ops_*
1198 *
1199 * Pattern 2:
1200 * Many drivers utilise a *driver container with references to
1201 * add, remove, probe functions etc.
1202 * the pattern is identified by:
1203 * tosec = init or exit section
1204 * fromsec = data section
1205 * atsym = *driver, *_template, *_sht, *_ops, *_probe,
1206 * *probe_one, *_console, *_timer
1207 *
1208 * Pattern 3:
1209 * Whitelist all references from .head.text to any init section
1210 *
1211 * Pattern 4:
1212 * Some symbols belong to init section but still it is ok to reference
1213 * these from non-init sections as these symbols don't have any memory
1214 * allocated for them and symbol address and value are same. So even
1215 * if init section is freed, its ok to reference those symbols.
1216 * For ex. symbols marking the init section boundaries.
1217 * This pattern is identified by
1218 * refsymname = __init_begin, _sinittext, _einittext
1219 *
1220 * Pattern 5:
1221 * GCC may optimize static inlines when fed constant arg(s) resulting
1222 * in functions like cpumask_empty() -- generating an associated symbol
1223 * cpumask_empty.constprop.3 that appears in the audit. If the const that
1224 * is passed in comes from __init, like say nmi_ipi_mask, we get a
1225 * meaningless section warning. May need to add isra symbols too...
1226 * This pattern is identified by
1227 * tosec = init section
1228 * fromsec = text section
1229 * refsymname = *.constprop.*
1230 *
1231 * Pattern 6:
1232 * Hide section mismatch warnings for ELF local symbols. The goal
1233 * is to eliminate false positive modpost warnings caused by
1234 * compiler-generated ELF local symbol names such as ".LANCHOR1".
1235 * Autogenerated symbol names bypass modpost's "Pattern 2"
1236 * whitelisting, which relies on pattern-matching against symbol
1237 * names to work. (One situation where gcc can autogenerate ELF
1238 * local symbols is when "-fsection-anchors" is used.)
1239 **/
1240static int secref_whitelist(const struct sectioncheck *mismatch,
1241 const char *fromsec, const char *fromsym,
1242 const char *tosec, const char *tosym)
1243{
1244 /* Check for pattern 1 */
1245 if (match(tosec, init_data_sections) &&
1246 match(fromsec, data_sections) &&
1247 strstarts(fromsym, "__param"))
1248 return 0;
1249
1250 /* Check for pattern 1a */
1251 if (strcmp(tosec, ".init.text") == 0 &&
1252 match(fromsec, data_sections) &&
1253 strstarts(fromsym, "__param_ops_"))
1254 return 0;
1255
1256 /* Check for pattern 2 */
1257 if (match(tosec, init_exit_sections) &&
1258 match(fromsec, data_sections) &&
1259 match(fromsym, mismatch->symbol_white_list))
1260 return 0;
1261
1262 /* Check for pattern 3 */
1263 if (match(fromsec, head_sections) &&
1264 match(tosec, init_sections))
1265 return 0;
1266
1267 /* Check for pattern 4 */
1268 if (match(tosym, linker_symbols))
1269 return 0;
1270
1271 /* Check for pattern 5 */
1272 if (match(fromsec, text_sections) &&
1273 match(tosec, init_sections) &&
1274 match(fromsym, optim_symbols))
1275 return 0;
1276
1277 /* Check for pattern 6 */
1278 if (strstarts(fromsym, ".L"))
1279 return 0;
1280
1281 return 1;
1282}
1283
1284static inline int is_arm_mapping_symbol(const char *str)
1285{
1286 return str[0] == '$' && strchr("axtd", str[1])
1287 && (str[2] == '\0' || str[2] == '.');
1288}
1289
1290/*
1291 * If there's no name there, ignore it; likewise, ignore it if it's
1292 * one of the magic symbols emitted used by current ARM tools.
1293 *
1294 * Otherwise if find_symbols_between() returns those symbols, they'll
1295 * fail the whitelist tests and cause lots of false alarms ... fixable
1296 * only by merging __exit and __init sections into __text, bloating
1297 * the kernel (which is especially evil on embedded platforms).
1298 */
1299static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
1300{
1301 const char *name = elf->strtab + sym->st_name;
1302
1303 if (!name || !strlen(name))
1304 return 0;
1305 return !is_arm_mapping_symbol(name);
1306}
1307
1308/**
1309 * Find symbol based on relocation record info.
1310 * In some cases the symbol supplied is a valid symbol so
1311 * return refsym. If st_name != 0 we assume this is a valid symbol.
1312 * In other cases the symbol needs to be looked up in the symbol table
1313 * based on section and address.
1314 * **/
1315static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
1316 Elf_Sym *relsym)
1317{
1318 Elf_Sym *sym;
1319 Elf_Sym *near = NULL;
1320 Elf64_Sword distance = 20;
1321 Elf64_Sword d;
1322 unsigned int relsym_secindex;
1323
1324 if (relsym->st_name != 0)
1325 return relsym;
1326
1327 relsym_secindex = get_secindex(elf, relsym);
1328 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1329 if (get_secindex(elf, sym) != relsym_secindex)
1330 continue;
1331 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
1332 continue;
1333 if (!is_valid_name(elf, sym))
1334 continue;
1335 if (sym->st_value == addr)
1336 return sym;
1337 /* Find a symbol nearby - addr are maybe negative */
1338 d = sym->st_value - addr;
1339 if (d < 0)
1340 d = addr - sym->st_value;
1341 if (d < distance) {
1342 distance = d;
1343 near = sym;
1344 }
1345 }
1346 /* We need a close match */
1347 if (distance < 20)
1348 return near;
1349 else
1350 return NULL;
1351}
1352
1353/*
1354 * Find symbols before or equal addr and after addr - in the section sec.
1355 * If we find two symbols with equal offset prefer one with a valid name.
1356 * The ELF format may have a better way to detect what type of symbol
1357 * it is, but this works for now.
1358 **/
1359static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
1360 const char *sec)
1361{
1362 Elf_Sym *sym;
1363 Elf_Sym *near = NULL;
1364 Elf_Addr distance = ~0;
1365
1366 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1367 const char *symsec;
1368
1369 if (is_shndx_special(sym->st_shndx))
1370 continue;
1371 symsec = sec_name(elf, get_secindex(elf, sym));
1372 if (strcmp(symsec, sec) != 0)
1373 continue;
1374 if (!is_valid_name(elf, sym))
1375 continue;
1376 if (sym->st_value <= addr) {
1377 if ((addr - sym->st_value) < distance) {
1378 distance = addr - sym->st_value;
1379 near = sym;
1380 } else if ((addr - sym->st_value) == distance) {
1381 near = sym;
1382 }
1383 }
1384 }
1385 return near;
1386}
1387
1388/*
1389 * Convert a section name to the function/data attribute
1390 * .init.text => __init
1391 * .memexitconst => __memconst
1392 * etc.
1393 *
1394 * The memory of returned value has been allocated on a heap. The user of this
1395 * method should free it after usage.
1396*/
1397static char *sec2annotation(const char *s)
1398{
1399 if (match(s, init_exit_sections)) {
1400 char *p = NOFAIL(malloc(20));
1401 char *r = p;
1402
1403 *p++ = '_';
1404 *p++ = '_';
1405 if (*s == '.')
1406 s++;
1407 while (*s && *s != '.')
1408 *p++ = *s++;
1409 *p = '\0';
1410 if (*s == '.')
1411 s++;
1412 if (strstr(s, "rodata") != NULL)
1413 strcat(p, "const ");
1414 else if (strstr(s, "data") != NULL)
1415 strcat(p, "data ");
1416 else
1417 strcat(p, " ");
1418 return r;
1419 } else {
1420 return NOFAIL(strdup(""));
1421 }
1422}
1423
1424static int is_function(Elf_Sym *sym)
1425{
1426 if (sym)
1427 return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
1428 else
1429 return -1;
1430}
1431
1432static void print_section_list(const char * const list[20])
1433{
1434 const char *const *s = list;
1435
1436 while (*s) {
1437 fprintf(stderr, "%s", *s);
1438 s++;
1439 if (*s)
1440 fprintf(stderr, ", ");
1441 }
1442 fprintf(stderr, "\n");
1443}
1444
1445static inline void get_pretty_name(int is_func, const char** name, const char** name_p)
1446{
1447 switch (is_func) {
1448 case 0: *name = "variable"; *name_p = ""; break;
1449 case 1: *name = "function"; *name_p = "()"; break;
1450 default: *name = "(unknown reference)"; *name_p = ""; break;
1451 }
1452}
1453
1454/*
1455 * Print a warning about a section mismatch.
1456 * Try to find symbols near it so user can find it.
1457 * Check whitelist before warning - it may be a false positive.
1458 */
1459static void report_sec_mismatch(const char *modname,
1460 const struct sectioncheck *mismatch,
1461 const char *fromsec,
1462 unsigned long long fromaddr,
1463 const char *fromsym,
1464 int from_is_func,
1465 const char *tosec, const char *tosym,
1466 int to_is_func)
1467{
1468 const char *from, *from_p;
1469 const char *to, *to_p;
1470 char *prl_from;
1471 char *prl_to;
1472
1473 sec_mismatch_count++;
1474
1475 get_pretty_name(from_is_func, &from, &from_p);
1476 get_pretty_name(to_is_func, &to, &to_p);
1477
1478 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1479 "to the %s %s:%s%s\n",
1480 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
1481 tosym, to_p);
1482
1483 switch (mismatch->mismatch) {
1484 case TEXT_TO_ANY_INIT:
1485 prl_from = sec2annotation(fromsec);
1486 prl_to = sec2annotation(tosec);
1487 fprintf(stderr,
1488 "The function %s%s() references\n"
1489 "the %s %s%s%s.\n"
1490 "This is often because %s lacks a %s\n"
1491 "annotation or the annotation of %s is wrong.\n",
1492 prl_from, fromsym,
1493 to, prl_to, tosym, to_p,
1494 fromsym, prl_to, tosym);
1495 free(prl_from);
1496 free(prl_to);
1497 break;
1498 case DATA_TO_ANY_INIT: {
1499 prl_to = sec2annotation(tosec);
1500 fprintf(stderr,
1501 "The variable %s references\n"
1502 "the %s %s%s%s\n"
1503 "If the reference is valid then annotate the\n"
1504 "variable with __init* or __refdata (see linux/init.h) "
1505 "or name the variable:\n",
1506 fromsym, to, prl_to, tosym, to_p);
1507 print_section_list(mismatch->symbol_white_list);
1508 free(prl_to);
1509 break;
1510 }
1511 case TEXT_TO_ANY_EXIT:
1512 prl_to = sec2annotation(tosec);
1513 fprintf(stderr,
1514 "The function %s() references a %s in an exit section.\n"
1515 "Often the %s %s%s has valid usage outside the exit section\n"
1516 "and the fix is to remove the %sannotation of %s.\n",
1517 fromsym, to, to, tosym, to_p, prl_to, tosym);
1518 free(prl_to);
1519 break;
1520 case DATA_TO_ANY_EXIT: {
1521 prl_to = sec2annotation(tosec);
1522 fprintf(stderr,
1523 "The variable %s references\n"
1524 "the %s %s%s%s\n"
1525 "If the reference is valid then annotate the\n"
1526 "variable with __exit* (see linux/init.h) or "
1527 "name the variable:\n",
1528 fromsym, to, prl_to, tosym, to_p);
1529 print_section_list(mismatch->symbol_white_list);
1530 free(prl_to);
1531 break;
1532 }
1533 case XXXINIT_TO_SOME_INIT:
1534 case XXXEXIT_TO_SOME_EXIT:
1535 prl_from = sec2annotation(fromsec);
1536 prl_to = sec2annotation(tosec);
1537 fprintf(stderr,
1538 "The %s %s%s%s references\n"
1539 "a %s %s%s%s.\n"
1540 "If %s is only used by %s then\n"
1541 "annotate %s with a matching annotation.\n",
1542 from, prl_from, fromsym, from_p,
1543 to, prl_to, tosym, to_p,
1544 tosym, fromsym, tosym);
1545 free(prl_from);
1546 free(prl_to);
1547 break;
1548 case ANY_INIT_TO_ANY_EXIT:
1549 prl_from = sec2annotation(fromsec);
1550 prl_to = sec2annotation(tosec);
1551 fprintf(stderr,
1552 "The %s %s%s%s references\n"
1553 "a %s %s%s%s.\n"
1554 "This is often seen when error handling "
1555 "in the init function\n"
1556 "uses functionality in the exit path.\n"
1557 "The fix is often to remove the %sannotation of\n"
1558 "%s%s so it may be used outside an exit section.\n",
1559 from, prl_from, fromsym, from_p,
1560 to, prl_to, tosym, to_p,
1561 prl_to, tosym, to_p);
1562 free(prl_from);
1563 free(prl_to);
1564 break;
1565 case ANY_EXIT_TO_ANY_INIT:
1566 prl_from = sec2annotation(fromsec);
1567 prl_to = sec2annotation(tosec);
1568 fprintf(stderr,
1569 "The %s %s%s%s references\n"
1570 "a %s %s%s%s.\n"
1571 "This is often seen when error handling "
1572 "in the exit function\n"
1573 "uses functionality in the init path.\n"
1574 "The fix is often to remove the %sannotation of\n"
1575 "%s%s so it may be used outside an init section.\n",
1576 from, prl_from, fromsym, from_p,
1577 to, prl_to, tosym, to_p,
1578 prl_to, tosym, to_p);
1579 free(prl_from);
1580 free(prl_to);
1581 break;
1582 case EXPORT_TO_INIT_EXIT:
1583 prl_to = sec2annotation(tosec);
1584 fprintf(stderr,
1585 "The symbol %s is exported and annotated %s\n"
1586 "Fix this by removing the %sannotation of %s "
1587 "or drop the export.\n",
1588 tosym, prl_to, prl_to, tosym);
1589 free(prl_to);
1590 break;
1591 case EXTABLE_TO_NON_TEXT:
1592 fatal("There's a special handler for this mismatch type, "
1593 "we should never get here.");
1594 break;
1595 }
1596 fprintf(stderr, "\n");
1597}
1598
1599static void default_mismatch_handler(const char *modname, struct elf_info *elf,
1600 const struct sectioncheck* const mismatch,
1601 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1602{
1603 const char *tosec;
1604 Elf_Sym *to;
1605 Elf_Sym *from;
1606 const char *tosym;
1607 const char *fromsym;
1608
1609 from = find_elf_symbol2(elf, r->r_offset, fromsec);
1610 fromsym = sym_name(elf, from);
1611
1612 if (strstarts(fromsym, "reference___initcall"))
1613 return;
1614
1615 tosec = sec_name(elf, get_secindex(elf, sym));
1616 to = find_elf_symbol(elf, r->r_addend, sym);
1617 tosym = sym_name(elf, to);
1618
1619 /* check whitelist - we may ignore it */
1620 if (secref_whitelist(mismatch,
1621 fromsec, fromsym, tosec, tosym)) {
1622 report_sec_mismatch(modname, mismatch,
1623 fromsec, r->r_offset, fromsym,
1624 is_function(from), tosec, tosym,
1625 is_function(to));
1626 }
1627}
1628
1629static int is_executable_section(struct elf_info* elf, unsigned int section_index)
1630{
1631 if (section_index > elf->num_sections)
1632 fatal("section_index is outside elf->num_sections!\n");
1633
1634 return ((elf->sechdrs[section_index].sh_flags & SHF_EXECINSTR) == SHF_EXECINSTR);
1635}
1636
1637/*
1638 * We rely on a gross hack in section_rel[a]() calling find_extable_entry_size()
1639 * to know the sizeof(struct exception_table_entry) for the target architecture.
1640 */
1641static unsigned int extable_entry_size = 0;
1642static void find_extable_entry_size(const char* const sec, const Elf_Rela* r)
1643{
1644 /*
1645 * If we're currently checking the second relocation within __ex_table,
1646 * that relocation offset tells us the offsetof(struct
1647 * exception_table_entry, fixup) which is equal to sizeof(struct
1648 * exception_table_entry) divided by two. We use that to our advantage
1649 * since there's no portable way to get that size as every architecture
1650 * seems to go with different sized types. Not pretty but better than
1651 * hard-coding the size for every architecture..
1652 */
1653 if (!extable_entry_size)
1654 extable_entry_size = r->r_offset * 2;
1655}
1656
1657static inline bool is_extable_fault_address(Elf_Rela *r)
1658{
1659 /*
1660 * extable_entry_size is only discovered after we've handled the
1661 * _second_ relocation in __ex_table, so only abort when we're not
1662 * handling the first reloc and extable_entry_size is zero.
1663 */
1664 if (r->r_offset && extable_entry_size == 0)
1665 fatal("extable_entry size hasn't been discovered!\n");
1666
1667 return ((r->r_offset == 0) ||
1668 (r->r_offset % extable_entry_size == 0));
1669}
1670
1671#define is_second_extable_reloc(Start, Cur, Sec) \
1672 (((Cur) == (Start) + 1) && (strcmp("__ex_table", (Sec)) == 0))
1673
1674static void report_extable_warnings(const char* modname, struct elf_info* elf,
1675 const struct sectioncheck* const mismatch,
1676 Elf_Rela* r, Elf_Sym* sym,
1677 const char* fromsec, const char* tosec)
1678{
1679 Elf_Sym* fromsym = find_elf_symbol2(elf, r->r_offset, fromsec);
1680 const char* fromsym_name = sym_name(elf, fromsym);
1681 Elf_Sym* tosym = find_elf_symbol(elf, r->r_addend, sym);
1682 const char* tosym_name = sym_name(elf, tosym);
1683 const char* from_pretty_name;
1684 const char* from_pretty_name_p;
1685 const char* to_pretty_name;
1686 const char* to_pretty_name_p;
1687
1688 get_pretty_name(is_function(fromsym),
1689 &from_pretty_name, &from_pretty_name_p);
1690 get_pretty_name(is_function(tosym),
1691 &to_pretty_name, &to_pretty_name_p);
1692
1693 warn("%s(%s+0x%lx): Section mismatch in reference"
1694 " from the %s %s%s to the %s %s:%s%s\n",
1695 modname, fromsec, (long)r->r_offset, from_pretty_name,
1696 fromsym_name, from_pretty_name_p,
1697 to_pretty_name, tosec, tosym_name, to_pretty_name_p);
1698
1699 if (!match(tosec, mismatch->bad_tosec) &&
1700 is_executable_section(elf, get_secindex(elf, sym)))
1701 fprintf(stderr,
1702 "The relocation at %s+0x%lx references\n"
1703 "section \"%s\" which is not in the list of\n"
1704 "authorized sections. If you're adding a new section\n"
1705 "and/or if this reference is valid, add \"%s\" to the\n"
1706 "list of authorized sections to jump to on fault.\n"
1707 "This can be achieved by adding \"%s\" to \n"
1708 "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n",
1709 fromsec, (long)r->r_offset, tosec, tosec, tosec);
1710}
1711
1712static void extable_mismatch_handler(const char* modname, struct elf_info *elf,
1713 const struct sectioncheck* const mismatch,
1714 Elf_Rela* r, Elf_Sym* sym,
1715 const char *fromsec)
1716{
1717 const char* tosec = sec_name(elf, get_secindex(elf, sym));
1718
1719 sec_mismatch_count++;
1720
1721 report_extable_warnings(modname, elf, mismatch, r, sym, fromsec, tosec);
1722
1723 if (match(tosec, mismatch->bad_tosec))
1724 fatal("The relocation at %s+0x%lx references\n"
1725 "section \"%s\" which is black-listed.\n"
1726 "Something is seriously wrong and should be fixed.\n"
1727 "You might get more information about where this is\n"
1728 "coming from by using scripts/check_extable.sh %s\n",
1729 fromsec, (long)r->r_offset, tosec, modname);
1730 else if (!is_executable_section(elf, get_secindex(elf, sym))) {
1731 if (is_extable_fault_address(r))
1732 fatal("The relocation at %s+0x%lx references\n"
1733 "section \"%s\" which is not executable, IOW\n"
1734 "it is not possible for the kernel to fault\n"
1735 "at that address. Something is seriously wrong\n"
1736 "and should be fixed.\n",
1737 fromsec, (long)r->r_offset, tosec);
1738 else
1739 fatal("The relocation at %s+0x%lx references\n"
1740 "section \"%s\" which is not executable, IOW\n"
1741 "the kernel will fault if it ever tries to\n"
1742 "jump to it. Something is seriously wrong\n"
1743 "and should be fixed.\n",
1744 fromsec, (long)r->r_offset, tosec);
1745 }
1746}
1747
1748static void check_section_mismatch(const char *modname, struct elf_info *elf,
1749 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1750{
1751 const char *tosec = sec_name(elf, get_secindex(elf, sym));
1752 const struct sectioncheck *mismatch = section_mismatch(fromsec, tosec);
1753
1754 if (mismatch) {
1755 if (mismatch->handler)
1756 mismatch->handler(modname, elf, mismatch,
1757 r, sym, fromsec);
1758 else
1759 default_mismatch_handler(modname, elf, mismatch,
1760 r, sym, fromsec);
1761 }
1762}
1763
1764static unsigned int *reloc_location(struct elf_info *elf,
1765 Elf_Shdr *sechdr, Elf_Rela *r)
1766{
1767 Elf_Shdr *sechdrs = elf->sechdrs;
1768 int section = sechdr->sh_info;
1769
1770 return (void *)elf->hdr + sechdrs[section].sh_offset +
1771 r->r_offset;
1772}
1773
1774static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1775{
1776 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1777 unsigned int *location = reloc_location(elf, sechdr, r);
1778
1779 switch (r_typ) {
1780 case R_386_32:
1781 r->r_addend = TO_NATIVE(*location);
1782 break;
1783 case R_386_PC32:
1784 r->r_addend = TO_NATIVE(*location) + 4;
1785 /* For CONFIG_RELOCATABLE=y */
1786 if (elf->hdr->e_type == ET_EXEC)
1787 r->r_addend += r->r_offset;
1788 break;
1789 }
1790 return 0;
1791}
1792
1793#ifndef R_ARM_CALL
1794#define R_ARM_CALL 28
1795#endif
1796#ifndef R_ARM_JUMP24
1797#define R_ARM_JUMP24 29
1798#endif
1799
1800#ifndef R_ARM_THM_CALL
1801#define R_ARM_THM_CALL 10
1802#endif
1803#ifndef R_ARM_THM_JUMP24
1804#define R_ARM_THM_JUMP24 30
1805#endif
1806#ifndef R_ARM_THM_JUMP19
1807#define R_ARM_THM_JUMP19 51
1808#endif
1809
1810static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1811{
1812 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1813
1814 switch (r_typ) {
1815 case R_ARM_ABS32:
1816 /* From ARM ABI: (S + A) | T */
1817 r->r_addend = (int)(long)
1818 (elf->symtab_start + ELF_R_SYM(r->r_info));
1819 break;
1820 case R_ARM_PC24:
1821 case R_ARM_CALL:
1822 case R_ARM_JUMP24:
1823 case R_ARM_THM_CALL:
1824 case R_ARM_THM_JUMP24:
1825 case R_ARM_THM_JUMP19:
1826 /* From ARM ABI: ((S + A) | T) - P */
1827 r->r_addend = (int)(long)(elf->hdr +
1828 sechdr->sh_offset +
1829 (r->r_offset - sechdr->sh_addr));
1830 break;
1831 default:
1832 return 1;
1833 }
1834 return 0;
1835}
1836
1837static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1838{
1839 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1840 unsigned int *location = reloc_location(elf, sechdr, r);
1841 unsigned int inst;
1842
1843 if (r_typ == R_MIPS_HI16)
1844 return 1; /* skip this */
1845 inst = TO_NATIVE(*location);
1846 switch (r_typ) {
1847 case R_MIPS_LO16:
1848 r->r_addend = inst & 0xffff;
1849 break;
1850 case R_MIPS_26:
1851 r->r_addend = (inst & 0x03ffffff) << 2;
1852 break;
1853 case R_MIPS_32:
1854 r->r_addend = inst;
1855 break;
1856 }
1857 return 0;
1858}
1859
1860static void section_rela(const char *modname, struct elf_info *elf,
1861 Elf_Shdr *sechdr)
1862{
1863 Elf_Sym *sym;
1864 Elf_Rela *rela;
1865 Elf_Rela r;
1866 unsigned int r_sym;
1867 const char *fromsec;
1868
1869 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
1870 Elf_Rela *stop = (void *)start + sechdr->sh_size;
1871
1872 fromsec = sech_name(elf, sechdr);
1873 fromsec += strlen(".rela");
1874 /* if from section (name) is know good then skip it */
1875 if (match(fromsec, section_white_list))
1876 return;
1877
1878 for (rela = start; rela < stop; rela++) {
1879 r.r_offset = TO_NATIVE(rela->r_offset);
1880#if KERNEL_ELFCLASS == ELFCLASS64
1881 if (elf->hdr->e_machine == EM_MIPS) {
1882 unsigned int r_typ;
1883 r_sym = ELF64_MIPS_R_SYM(rela->r_info);
1884 r_sym = TO_NATIVE(r_sym);
1885 r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
1886 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1887 } else {
1888 r.r_info = TO_NATIVE(rela->r_info);
1889 r_sym = ELF_R_SYM(r.r_info);
1890 }
1891#else
1892 r.r_info = TO_NATIVE(rela->r_info);
1893 r_sym = ELF_R_SYM(r.r_info);
1894#endif
1895 r.r_addend = TO_NATIVE(rela->r_addend);
1896 sym = elf->symtab_start + r_sym;
1897 /* Skip special sections */
1898 if (is_shndx_special(sym->st_shndx))
1899 continue;
1900 if (is_second_extable_reloc(start, rela, fromsec))
1901 find_extable_entry_size(fromsec, &r);
1902 check_section_mismatch(modname, elf, &r, sym, fromsec);
1903 }
1904}
1905
1906static void section_rel(const char *modname, struct elf_info *elf,
1907 Elf_Shdr *sechdr)
1908{
1909 Elf_Sym *sym;
1910 Elf_Rel *rel;
1911 Elf_Rela r;
1912 unsigned int r_sym;
1913 const char *fromsec;
1914
1915 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
1916 Elf_Rel *stop = (void *)start + sechdr->sh_size;
1917
1918 fromsec = sech_name(elf, sechdr);
1919 fromsec += strlen(".rel");
1920 /* if from section (name) is know good then skip it */
1921 if (match(fromsec, section_white_list))
1922 return;
1923
1924 for (rel = start; rel < stop; rel++) {
1925 r.r_offset = TO_NATIVE(rel->r_offset);
1926#if KERNEL_ELFCLASS == ELFCLASS64
1927 if (elf->hdr->e_machine == EM_MIPS) {
1928 unsigned int r_typ;
1929 r_sym = ELF64_MIPS_R_SYM(rel->r_info);
1930 r_sym = TO_NATIVE(r_sym);
1931 r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
1932 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1933 } else {
1934 r.r_info = TO_NATIVE(rel->r_info);
1935 r_sym = ELF_R_SYM(r.r_info);
1936 }
1937#else
1938 r.r_info = TO_NATIVE(rel->r_info);
1939 r_sym = ELF_R_SYM(r.r_info);
1940#endif
1941 r.r_addend = 0;
1942 switch (elf->hdr->e_machine) {
1943 case EM_386:
1944 if (addend_386_rel(elf, sechdr, &r))
1945 continue;
1946 break;
1947 case EM_ARM:
1948 if (addend_arm_rel(elf, sechdr, &r))
1949 continue;
1950 break;
1951 case EM_MIPS:
1952 if (addend_mips_rel(elf, sechdr, &r))
1953 continue;
1954 break;
1955 }
1956 sym = elf->symtab_start + r_sym;
1957 /* Skip special sections */
1958 if (is_shndx_special(sym->st_shndx))
1959 continue;
1960 if (is_second_extable_reloc(start, rel, fromsec))
1961 find_extable_entry_size(fromsec, &r);
1962 check_section_mismatch(modname, elf, &r, sym, fromsec);
1963 }
1964}
1965
1966/**
1967 * A module includes a number of sections that are discarded
1968 * either when loaded or when used as built-in.
1969 * For loaded modules all functions marked __init and all data
1970 * marked __initdata will be discarded when the module has been initialized.
1971 * Likewise for modules used built-in the sections marked __exit
1972 * are discarded because __exit marked function are supposed to be called
1973 * only when a module is unloaded which never happens for built-in modules.
1974 * The check_sec_ref() function traverses all relocation records
1975 * to find all references to a section that reference a section that will
1976 * be discarded and warns about it.
1977 **/
1978static void check_sec_ref(struct module *mod, const char *modname,
1979 struct elf_info *elf)
1980{
1981 int i;
1982 Elf_Shdr *sechdrs = elf->sechdrs;
1983
1984 /* Walk through all sections */
1985 for (i = 0; i < elf->num_sections; i++) {
1986 check_section(modname, elf, &elf->sechdrs[i]);
1987 /* We want to process only relocation sections and not .init */
1988 if (sechdrs[i].sh_type == SHT_RELA)
1989 section_rela(modname, elf, &elf->sechdrs[i]);
1990 else if (sechdrs[i].sh_type == SHT_REL)
1991 section_rel(modname, elf, &elf->sechdrs[i]);
1992 }
1993}
1994
1995static char *remove_dot(char *s)
1996{
1997 size_t n = strcspn(s, ".");
1998
1999 if (n && s[n]) {
2000 size_t m = strspn(s + n + 1, "0123456789");
2001 if (m && (s[n + m] == '.' || s[n + m] == 0))
2002 s[n] = 0;
2003 }
2004 return s;
2005}
2006
2007static void read_symbols(const char *modname)
2008{
2009 const char *symname;
2010 char *version;
2011 char *license;
2012 char *namespace;
2013 struct module *mod;
2014 struct elf_info info = { };
2015 Elf_Sym *sym;
2016
2017 if (!parse_elf(&info, modname))
2018 return;
2019
2020 mod = new_module(modname);
2021
2022 /* When there's no vmlinux, don't print warnings about
2023 * unresolved symbols (since there'll be too many ;) */
2024 if (is_vmlinux(modname)) {
2025 have_vmlinux = 1;
2026 mod->skip = 1;
2027 }
2028
2029 license = get_modinfo(&info, "license");
2030 if (!license && !is_vmlinux(modname))
2031 warn("modpost: missing MODULE_LICENSE() in %s\n"
2032 "see include/linux/module.h for "
2033 "more information\n", modname);
2034 while (license) {
2035 if (license_is_gpl_compatible(license))
2036 mod->gpl_compatible = 1;
2037 else {
2038 mod->gpl_compatible = 0;
2039 break;
2040 }
2041 license = get_next_modinfo(&info, "license", license);
2042 }
2043
2044 namespace = get_modinfo(&info, "import_ns");
2045 while (namespace) {
2046 add_namespace(&mod->imported_namespaces, namespace);
2047 namespace = get_next_modinfo(&info, "import_ns", namespace);
2048 }
2049
2050 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
2051 symname = remove_dot(info.strtab + sym->st_name);
2052
2053 handle_modversions(mod, &info, sym, symname);
2054 handle_moddevtable(mod, &info, sym, symname);
2055 }
2056
2057 /* Apply symbol namespaces from __kstrtabns_<symbol> entries. */
2058 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
2059 symname = remove_dot(info.strtab + sym->st_name);
2060
2061 if (strstarts(symname, "__kstrtabns_"))
2062 sym_update_namespace(symname + strlen("__kstrtabns_"),
2063 namespace_from_kstrtabns(&info,
2064 sym));
2065 }
2066
2067 // check for static EXPORT_SYMBOL_* functions && global vars
2068 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
2069 unsigned char bind = ELF_ST_BIND(sym->st_info);
2070
2071 if (bind == STB_GLOBAL || bind == STB_WEAK) {
2072 struct symbol *s =
2073 find_symbol(remove_dot(info.strtab +
2074 sym->st_name));
2075
2076 if (s)
2077 s->is_static = 0;
2078 }
2079 }
2080
2081 if (!is_vmlinux(modname) || vmlinux_section_warnings)
2082 check_sec_ref(mod, modname, &info);
2083
2084 version = get_modinfo(&info, "version");
2085 if (version)
2086 maybe_frob_rcs_version(modname, version, info.modinfo,
2087 version - (char *)info.hdr);
2088 if (version || (all_versions && !is_vmlinux(modname)))
2089 get_src_version(modname, mod->srcversion,
2090 sizeof(mod->srcversion)-1);
2091
2092 parse_elf_finish(&info);
2093
2094 /* Our trick to get versioning for module struct etc. - it's
2095 * never passed as an argument to an exported function, so
2096 * the automatic versioning doesn't pick it up, but it's really
2097 * important anyhow */
2098 if (modversions)
2099 mod->unres = alloc_symbol("module_layout", 0, mod->unres);
2100}
2101
2102static void read_symbols_from_files(const char *filename)
2103{
2104 FILE *in = stdin;
2105 char fname[PATH_MAX];
2106
2107 if (strcmp(filename, "-") != 0) {
2108 in = fopen(filename, "r");
2109 if (!in)
2110 fatal("Can't open filenames file %s: %m", filename);
2111 }
2112
2113 while (fgets(fname, PATH_MAX, in) != NULL) {
2114 if (strends(fname, "\n"))
2115 fname[strlen(fname)-1] = '\0';
2116 read_symbols(fname);
2117 }
2118
2119 if (in != stdin)
2120 fclose(in);
2121}
2122
2123#define SZ 500
2124
2125/* We first write the generated file into memory using the
2126 * following helper, then compare to the file on disk and
2127 * only update the later if anything changed */
2128
2129void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
2130 const char *fmt, ...)
2131{
2132 char tmp[SZ];
2133 int len;
2134 va_list ap;
2135
2136 va_start(ap, fmt);
2137 len = vsnprintf(tmp, SZ, fmt, ap);
2138 buf_write(buf, tmp, len);
2139 va_end(ap);
2140}
2141
2142void buf_write(struct buffer *buf, const char *s, int len)
2143{
2144 if (buf->size - buf->pos < len) {
2145 buf->size += len + SZ;
2146 buf->p = NOFAIL(realloc(buf->p, buf->size));
2147 }
2148 strncpy(buf->p + buf->pos, s, len);
2149 buf->pos += len;
2150}
2151
2152static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
2153{
2154 const char *e = is_vmlinux(m) ?"":".ko";
2155
2156 switch (exp) {
2157 case export_gpl:
2158 fatal("modpost: GPL-incompatible module %s%s "
2159 "uses GPL-only symbol '%s'\n", m, e, s);
2160 break;
2161 case export_unused_gpl:
2162 fatal("modpost: GPL-incompatible module %s%s "
2163 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
2164 break;
2165 case export_gpl_future:
2166 warn("modpost: GPL-incompatible module %s%s "
2167 "uses future GPL-only symbol '%s'\n", m, e, s);
2168 break;
2169 case export_plain:
2170 case export_unused:
2171 case export_unknown:
2172 /* ignore */
2173 break;
2174 }
2175}
2176
2177static void check_for_unused(enum export exp, const char *m, const char *s)
2178{
2179 const char *e = is_vmlinux(m) ?"":".ko";
2180
2181 switch (exp) {
2182 case export_unused:
2183 case export_unused_gpl:
2184 warn("modpost: module %s%s "
2185 "uses symbol '%s' marked UNUSED\n", m, e, s);
2186 break;
2187 default:
2188 /* ignore */
2189 break;
2190 }
2191}
2192
2193static int check_exports(struct module *mod)
2194{
2195 struct symbol *s, *exp;
2196 int err = 0;
2197
2198 for (s = mod->unres; s; s = s->next) {
2199 const char *basename;
2200 exp = find_symbol(s->name);
2201 if (!exp || exp->module == mod) {
2202 if (have_vmlinux && !s->weak) {
2203 if (warn_unresolved) {
2204 warn("\"%s\" [%s.ko] undefined!\n",
2205 s->name, mod->name);
2206 } else {
2207 merror("\"%s\" [%s.ko] undefined!\n",
2208 s->name, mod->name);
2209 err = 1;
2210 }
2211 }
2212 continue;
2213 }
2214 basename = strrchr(mod->name, '/');
2215 if (basename)
2216 basename++;
2217 else
2218 basename = mod->name;
2219
2220 if (exp->namespace) {
2221 add_namespace(&mod->required_namespaces,
2222 exp->namespace);
2223
2224 if (!write_namespace_deps &&
2225 !module_imports_namespace(mod, exp->namespace)) {
2226 warn("module %s uses symbol %s from namespace %s, but does not import it.\n",
2227 basename, exp->name, exp->namespace);
2228 }
2229 }
2230
2231 if (!mod->gpl_compatible)
2232 check_for_gpl_usage(exp->export, basename, exp->name);
2233 check_for_unused(exp->export, basename, exp->name);
2234 }
2235
2236 return err;
2237}
2238
2239static int check_modname_len(struct module *mod)
2240{
2241 const char *mod_name;
2242
2243 mod_name = strrchr(mod->name, '/');
2244 if (mod_name == NULL)
2245 mod_name = mod->name;
2246 else
2247 mod_name++;
2248 if (strlen(mod_name) >= MODULE_NAME_LEN) {
2249 merror("module name is too long [%s.ko]\n", mod->name);
2250 return 1;
2251 }
2252
2253 return 0;
2254}
2255
2256/**
2257 * Header for the generated file
2258 **/
2259static void add_header(struct buffer *b, struct module *mod)
2260{
2261 buf_printf(b, "#include <linux/build-salt.h>\n");
2262 buf_printf(b, "#include <linux/module.h>\n");
2263 buf_printf(b, "#include <linux/vermagic.h>\n");
2264 buf_printf(b, "#include <linux/compiler.h>\n");
2265 buf_printf(b, "\n");
2266 buf_printf(b, "BUILD_SALT;\n");
2267 buf_printf(b, "\n");
2268 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
2269 buf_printf(b, "MODULE_INFO(name, KBUILD_MODNAME);\n");
2270 buf_printf(b, "\n");
2271 buf_printf(b, "__visible struct module __this_module\n");
2272 buf_printf(b, "__section(.gnu.linkonce.this_module) = {\n");
2273 buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
2274 if (mod->has_init)
2275 buf_printf(b, "\t.init = init_module,\n");
2276 if (mod->has_cleanup)
2277 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
2278 "\t.exit = cleanup_module,\n"
2279 "#endif\n");
2280 buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
2281 buf_printf(b, "};\n");
2282}
2283
2284static void add_intree_flag(struct buffer *b, int is_intree)
2285{
2286 if (is_intree)
2287 buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
2288}
2289
2290/* Cannot check for assembler */
2291static void add_retpoline(struct buffer *b)
2292{
2293 buf_printf(b, "\n#ifdef CONFIG_RETPOLINE\n");
2294 buf_printf(b, "MODULE_INFO(retpoline, \"Y\");\n");
2295 buf_printf(b, "#endif\n");
2296}
2297
2298static void add_staging_flag(struct buffer *b, const char *name)
2299{
2300 if (strstarts(name, "drivers/staging"))
2301 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
2302}
2303
2304/**
2305 * Record CRCs for unresolved symbols
2306 **/
2307static int add_versions(struct buffer *b, struct module *mod)
2308{
2309 struct symbol *s, *exp;
2310 int err = 0;
2311
2312 for (s = mod->unres; s; s = s->next) {
2313 exp = find_symbol(s->name);
2314 if (!exp || exp->module == mod)
2315 continue;
2316 s->module = exp->module;
2317 s->crc_valid = exp->crc_valid;
2318 s->crc = exp->crc;
2319 }
2320
2321 if (!modversions)
2322 return err;
2323
2324 buf_printf(b, "\n");
2325 buf_printf(b, "static const struct modversion_info ____versions[]\n");
2326 buf_printf(b, "__used __section(__versions) = {\n");
2327
2328 for (s = mod->unres; s; s = s->next) {
2329 if (!s->module)
2330 continue;
2331 if (!s->crc_valid) {
2332 warn("\"%s\" [%s.ko] has no CRC!\n",
2333 s->name, mod->name);
2334 continue;
2335 }
2336 if (strlen(s->name) >= MODULE_NAME_LEN) {
2337 merror("too long symbol \"%s\" [%s.ko]\n",
2338 s->name, mod->name);
2339 err = 1;
2340 break;
2341 }
2342 buf_printf(b, "\t{ %#8x, \"%s\" },\n",
2343 s->crc, s->name);
2344 }
2345
2346 buf_printf(b, "};\n");
2347
2348 return err;
2349}
2350
2351static void add_depends(struct buffer *b, struct module *mod)
2352{
2353 struct symbol *s;
2354 int first = 1;
2355
2356 /* Clear ->seen flag of modules that own symbols needed by this. */
2357 for (s = mod->unres; s; s = s->next)
2358 if (s->module)
2359 s->module->seen = is_vmlinux(s->module->name);
2360
2361 buf_printf(b, "\n");
2362 buf_printf(b, "MODULE_INFO(depends, \"");
2363 for (s = mod->unres; s; s = s->next) {
2364 const char *p;
2365 if (!s->module)
2366 continue;
2367
2368 if (s->module->seen)
2369 continue;
2370
2371 s->module->seen = 1;
2372 p = strrchr(s->module->name, '/');
2373 if (p)
2374 p++;
2375 else
2376 p = s->module->name;
2377 buf_printf(b, "%s%s", first ? "" : ",", p);
2378 first = 0;
2379 }
2380 buf_printf(b, "\");\n");
2381}
2382
2383static void add_srcversion(struct buffer *b, struct module *mod)
2384{
2385 if (mod->srcversion[0]) {
2386 buf_printf(b, "\n");
2387 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
2388 mod->srcversion);
2389 }
2390}
2391
2392static void write_if_changed(struct buffer *b, const char *fname)
2393{
2394 char *tmp;
2395 FILE *file;
2396 struct stat st;
2397
2398 file = fopen(fname, "r");
2399 if (!file)
2400 goto write;
2401
2402 if (fstat(fileno(file), &st) < 0)
2403 goto close_write;
2404
2405 if (st.st_size != b->pos)
2406 goto close_write;
2407
2408 tmp = NOFAIL(malloc(b->pos));
2409 if (fread(tmp, 1, b->pos, file) != b->pos)
2410 goto free_write;
2411
2412 if (memcmp(tmp, b->p, b->pos) != 0)
2413 goto free_write;
2414
2415 free(tmp);
2416 fclose(file);
2417 return;
2418
2419 free_write:
2420 free(tmp);
2421 close_write:
2422 fclose(file);
2423 write:
2424 file = fopen(fname, "w");
2425 if (!file) {
2426 perror(fname);
2427 exit(1);
2428 }
2429 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
2430 perror(fname);
2431 exit(1);
2432 }
2433 fclose(file);
2434}
2435
2436/* parse Module.symvers file. line format:
2437 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
2438 **/
2439static void read_dump(const char *fname, unsigned int kernel)
2440{
2441 unsigned long size, pos = 0;
2442 void *file = grab_file(fname, &size);
2443 char *line;
2444
2445 if (!file)
2446 /* No symbol versions, silently ignore */
2447 return;
2448
2449 while ((line = get_next_line(&pos, file, size))) {
2450 char *symname, *namespace, *modname, *d, *export, *end;
2451 unsigned int crc;
2452 struct module *mod;
2453 struct symbol *s;
2454
2455 if (!(symname = strchr(line, '\t')))
2456 goto fail;
2457 *symname++ = '\0';
2458 if (!(namespace = strchr(symname, '\t')))
2459 goto fail;
2460 *namespace++ = '\0';
2461 if (!(modname = strchr(namespace, '\t')))
2462 goto fail;
2463 *modname++ = '\0';
2464 if ((export = strchr(modname, '\t')) != NULL)
2465 *export++ = '\0';
2466 if (export && ((end = strchr(export, '\t')) != NULL))
2467 *end = '\0';
2468 crc = strtoul(line, &d, 16);
2469 if (*symname == '\0' || *modname == '\0' || *d != '\0')
2470 goto fail;
2471 mod = find_module(modname);
2472 if (!mod) {
2473 if (is_vmlinux(modname))
2474 have_vmlinux = 1;
2475 mod = new_module(modname);
2476 mod->skip = 1;
2477 }
2478 s = sym_add_exported(symname, mod, export_no(export));
2479 s->kernel = kernel;
2480 s->preloaded = 1;
2481 s->is_static = 0;
2482 sym_update_crc(symname, mod, crc, export_no(export));
2483 sym_update_namespace(symname, namespace);
2484 }
2485 release_file(file, size);
2486 return;
2487fail:
2488 release_file(file, size);
2489 fatal("parse error in symbol dump file\n");
2490}
2491
2492/* For normal builds always dump all symbols.
2493 * For external modules only dump symbols
2494 * that are not read from kernel Module.symvers.
2495 **/
2496static int dump_sym(struct symbol *sym)
2497{
2498 if (!external_module)
2499 return 1;
2500 if (sym->vmlinux || sym->kernel)
2501 return 0;
2502 return 1;
2503}
2504
2505static void write_dump(const char *fname)
2506{
2507 struct buffer buf = { };
2508 struct symbol *symbol;
2509 const char *namespace;
2510 int n;
2511
2512 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
2513 symbol = symbolhash[n];
2514 while (symbol) {
2515 if (dump_sym(symbol)) {
2516 namespace = symbol->namespace;
2517 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\t%s\n",
2518 symbol->crc, symbol->name,
2519 namespace ? namespace : "",
2520 symbol->module->name,
2521 export_str(symbol->export));
2522 }
2523 symbol = symbol->next;
2524 }
2525 }
2526 write_if_changed(&buf, fname);
2527 free(buf.p);
2528}
2529
2530static void write_namespace_deps_files(void)
2531{
2532 struct module *mod;
2533 struct namespace_list *ns;
2534 struct buffer ns_deps_buf = {};
2535
2536 for (mod = modules; mod; mod = mod->next) {
2537 char fname[PATH_MAX];
2538
2539 if (mod->skip)
2540 continue;
2541
2542 ns_deps_buf.pos = 0;
2543
2544 for (ns = mod->required_namespaces; ns; ns = ns->next)
2545 buf_printf(&ns_deps_buf, "%s\n", ns->namespace);
2546
2547 if (ns_deps_buf.pos == 0)
2548 continue;
2549
2550 sprintf(fname, "%s.ns_deps", mod->name);
2551 write_if_changed(&ns_deps_buf, fname);
2552 }
2553}
2554
2555struct ext_sym_list {
2556 struct ext_sym_list *next;
2557 const char *file;
2558};
2559
2560int main(int argc, char **argv)
2561{
2562 struct module *mod;
2563 struct buffer buf = { };
2564 char *kernel_read = NULL, *module_read = NULL;
2565 char *dump_write = NULL, *files_source = NULL;
2566 int opt;
2567 int err;
2568 int n;
2569 struct ext_sym_list *extsym_iter;
2570 struct ext_sym_list *extsym_start = NULL;
2571
2572 while ((opt = getopt(argc, argv, "i:I:e:mnsT:o:awEd")) != -1) {
2573 switch (opt) {
2574 case 'i':
2575 kernel_read = optarg;
2576 break;
2577 case 'I':
2578 module_read = optarg;
2579 external_module = 1;
2580 break;
2581 case 'e':
2582 external_module = 1;
2583 extsym_iter =
2584 NOFAIL(malloc(sizeof(*extsym_iter)));
2585 extsym_iter->next = extsym_start;
2586 extsym_iter->file = optarg;
2587 extsym_start = extsym_iter;
2588 break;
2589 case 'm':
2590 modversions = 1;
2591 break;
2592 case 'n':
2593 ignore_missing_files = 1;
2594 break;
2595 case 'o':
2596 dump_write = optarg;
2597 break;
2598 case 'a':
2599 all_versions = 1;
2600 break;
2601 case 's':
2602 vmlinux_section_warnings = 0;
2603 break;
2604 case 'T':
2605 files_source = optarg;
2606 break;
2607 case 'w':
2608 warn_unresolved = 1;
2609 break;
2610 case 'E':
2611 sec_mismatch_fatal = 1;
2612 break;
2613 case 'd':
2614 write_namespace_deps = 1;
2615 break;
2616 default:
2617 exit(1);
2618 }
2619 }
2620
2621 if (kernel_read)
2622 read_dump(kernel_read, 1);
2623 if (module_read)
2624 read_dump(module_read, 0);
2625 while (extsym_start) {
2626 read_dump(extsym_start->file, 0);
2627 extsym_iter = extsym_start->next;
2628 free(extsym_start);
2629 extsym_start = extsym_iter;
2630 }
2631
2632 while (optind < argc)
2633 read_symbols(argv[optind++]);
2634
2635 if (files_source)
2636 read_symbols_from_files(files_source);
2637
2638 err = 0;
2639
2640 for (mod = modules; mod; mod = mod->next) {
2641 char fname[PATH_MAX];
2642
2643 if (mod->skip)
2644 continue;
2645
2646 buf.pos = 0;
2647
2648 err |= check_modname_len(mod);
2649 err |= check_exports(mod);
2650 if (write_namespace_deps)
2651 continue;
2652
2653 add_header(&buf, mod);
2654 add_intree_flag(&buf, !external_module);
2655 add_retpoline(&buf);
2656 add_staging_flag(&buf, mod->name);
2657 err |= add_versions(&buf, mod);
2658 add_depends(&buf, mod);
2659 add_moddevtable(&buf, mod);
2660 add_srcversion(&buf, mod);
2661
2662 sprintf(fname, "%s.mod.c", mod->name);
2663 write_if_changed(&buf, fname);
2664 }
2665
2666 if (write_namespace_deps) {
2667 write_namespace_deps_files();
2668 return 0;
2669 }
2670
2671 if (dump_write)
2672 write_dump(dump_write);
2673 if (sec_mismatch_count && sec_mismatch_fatal)
2674 fatal("modpost: Section mismatches detected.\n"
2675 "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n");
2676 for (n = 0; n < SYMBOL_HASH_SIZE; n++) {
2677 struct symbol *s;
2678
2679 for (s = symbolhash[n]; s; s = s->next) {
2680 /*
2681 * Do not check "vmlinux". This avoids the same warnings
2682 * shown twice, and false-positives for ARCH=um.
2683 */
2684 if (is_vmlinux(s->module->name) && !s->module->is_dot_o)
2685 continue;
2686
2687 if (s->is_static)
2688 warn("\"%s\" [%s] is a static %s\n",
2689 s->name, s->module->name,
2690 export_str(s->export));
2691 }
2692 }
2693
2694 free(buf.p);
2695
2696 return err;
2697}
1/* Postprocess module symbol versions
2 *
3 * Copyright 2003 Kai Germaschewski
4 * Copyright 2002-2004 Rusty Russell, IBM Corporation
5 * Copyright 2006-2008 Sam Ravnborg
6 * Based in part on module-init-tools/depmod.c,file2alias
7 *
8 * This software may be used and distributed according to the terms
9 * of the GNU General Public License, incorporated herein by reference.
10 *
11 * Usage: modpost vmlinux module1.o module2.o ...
12 */
13
14#define _GNU_SOURCE
15#include <stdio.h>
16#include <ctype.h>
17#include <string.h>
18#include "modpost.h"
19#include "../../include/generated/autoconf.h"
20#include "../../include/linux/license.h"
21
22/* Some toolchains use a `_' prefix for all user symbols. */
23#ifdef CONFIG_SYMBOL_PREFIX
24#define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX
25#else
26#define MODULE_SYMBOL_PREFIX ""
27#endif
28
29
30/* Are we using CONFIG_MODVERSIONS? */
31int modversions = 0;
32/* Warn about undefined symbols? (do so if we have vmlinux) */
33int have_vmlinux = 0;
34/* Is CONFIG_MODULE_SRCVERSION_ALL set? */
35static int all_versions = 0;
36/* If we are modposting external module set to 1 */
37static int external_module = 0;
38/* Warn about section mismatch in vmlinux if set to 1 */
39static int vmlinux_section_warnings = 1;
40/* Only warn about unresolved symbols */
41static int warn_unresolved = 0;
42/* How a symbol is exported */
43static int sec_mismatch_count = 0;
44static int sec_mismatch_verbose = 1;
45
46enum export {
47 export_plain, export_unused, export_gpl,
48 export_unused_gpl, export_gpl_future, export_unknown
49};
50
51#define PRINTF __attribute__ ((format (printf, 1, 2)))
52
53PRINTF void fatal(const char *fmt, ...)
54{
55 va_list arglist;
56
57 fprintf(stderr, "FATAL: ");
58
59 va_start(arglist, fmt);
60 vfprintf(stderr, fmt, arglist);
61 va_end(arglist);
62
63 exit(1);
64}
65
66PRINTF void warn(const char *fmt, ...)
67{
68 va_list arglist;
69
70 fprintf(stderr, "WARNING: ");
71
72 va_start(arglist, fmt);
73 vfprintf(stderr, fmt, arglist);
74 va_end(arglist);
75}
76
77PRINTF void merror(const char *fmt, ...)
78{
79 va_list arglist;
80
81 fprintf(stderr, "ERROR: ");
82
83 va_start(arglist, fmt);
84 vfprintf(stderr, fmt, arglist);
85 va_end(arglist);
86}
87
88static int is_vmlinux(const char *modname)
89{
90 const char *myname;
91
92 myname = strrchr(modname, '/');
93 if (myname)
94 myname++;
95 else
96 myname = modname;
97
98 return (strcmp(myname, "vmlinux") == 0) ||
99 (strcmp(myname, "vmlinux.o") == 0);
100}
101
102void *do_nofail(void *ptr, const char *expr)
103{
104 if (!ptr)
105 fatal("modpost: Memory allocation failure: %s.\n", expr);
106
107 return ptr;
108}
109
110/* A list of all modules we processed */
111static struct module *modules;
112
113static struct module *find_module(char *modname)
114{
115 struct module *mod;
116
117 for (mod = modules; mod; mod = mod->next)
118 if (strcmp(mod->name, modname) == 0)
119 break;
120 return mod;
121}
122
123static struct module *new_module(char *modname)
124{
125 struct module *mod;
126 char *p, *s;
127
128 mod = NOFAIL(malloc(sizeof(*mod)));
129 memset(mod, 0, sizeof(*mod));
130 p = NOFAIL(strdup(modname));
131
132 /* strip trailing .o */
133 s = strrchr(p, '.');
134 if (s != NULL)
135 if (strcmp(s, ".o") == 0)
136 *s = '\0';
137
138 /* add to list */
139 mod->name = p;
140 mod->gpl_compatible = -1;
141 mod->next = modules;
142 modules = mod;
143
144 return mod;
145}
146
147/* A hash of all exported symbols,
148 * struct symbol is also used for lists of unresolved symbols */
149
150#define SYMBOL_HASH_SIZE 1024
151
152struct symbol {
153 struct symbol *next;
154 struct module *module;
155 unsigned int crc;
156 int crc_valid;
157 unsigned int weak:1;
158 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */
159 unsigned int kernel:1; /* 1 if symbol is from kernel
160 * (only for external modules) **/
161 unsigned int preloaded:1; /* 1 if symbol from Module.symvers */
162 enum export export; /* Type of export */
163 char name[0];
164};
165
166static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
167
168/* This is based on the hash agorithm from gdbm, via tdb */
169static inline unsigned int tdb_hash(const char *name)
170{
171 unsigned value; /* Used to compute the hash value. */
172 unsigned i; /* Used to cycle through random values. */
173
174 /* Set the initial value from the key size. */
175 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++)
176 value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
177
178 return (1103515243 * value + 12345);
179}
180
181/**
182 * Allocate a new symbols for use in the hash of exported symbols or
183 * the list of unresolved symbols per module
184 **/
185static struct symbol *alloc_symbol(const char *name, unsigned int weak,
186 struct symbol *next)
187{
188 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
189
190 memset(s, 0, sizeof(*s));
191 strcpy(s->name, name);
192 s->weak = weak;
193 s->next = next;
194 return s;
195}
196
197/* For the hash of exported symbols */
198static struct symbol *new_symbol(const char *name, struct module *module,
199 enum export export)
200{
201 unsigned int hash;
202 struct symbol *new;
203
204 hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
205 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
206 new->module = module;
207 new->export = export;
208 return new;
209}
210
211static struct symbol *find_symbol(const char *name)
212{
213 struct symbol *s;
214
215 /* For our purposes, .foo matches foo. PPC64 needs this. */
216 if (name[0] == '.')
217 name++;
218
219 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
220 if (strcmp(s->name, name) == 0)
221 return s;
222 }
223 return NULL;
224}
225
226static struct {
227 const char *str;
228 enum export export;
229} export_list[] = {
230 { .str = "EXPORT_SYMBOL", .export = export_plain },
231 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
232 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
233 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
234 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
235 { .str = "(unknown)", .export = export_unknown },
236};
237
238
239static const char *export_str(enum export ex)
240{
241 return export_list[ex].str;
242}
243
244static enum export export_no(const char *s)
245{
246 int i;
247
248 if (!s)
249 return export_unknown;
250 for (i = 0; export_list[i].export != export_unknown; i++) {
251 if (strcmp(export_list[i].str, s) == 0)
252 return export_list[i].export;
253 }
254 return export_unknown;
255}
256
257static const char *sec_name(struct elf_info *elf, int secindex);
258
259#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
260
261static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
262{
263 const char *secname = sec_name(elf, sec);
264
265 if (strstarts(secname, "___ksymtab+"))
266 return export_plain;
267 else if (strstarts(secname, "___ksymtab_unused+"))
268 return export_unused;
269 else if (strstarts(secname, "___ksymtab_gpl+"))
270 return export_gpl;
271 else if (strstarts(secname, "___ksymtab_unused_gpl+"))
272 return export_unused_gpl;
273 else if (strstarts(secname, "___ksymtab_gpl_future+"))
274 return export_gpl_future;
275 else
276 return export_unknown;
277}
278
279static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
280{
281 if (sec == elf->export_sec)
282 return export_plain;
283 else if (sec == elf->export_unused_sec)
284 return export_unused;
285 else if (sec == elf->export_gpl_sec)
286 return export_gpl;
287 else if (sec == elf->export_unused_gpl_sec)
288 return export_unused_gpl;
289 else if (sec == elf->export_gpl_future_sec)
290 return export_gpl_future;
291 else
292 return export_unknown;
293}
294
295/**
296 * Add an exported symbol - it may have already been added without a
297 * CRC, in this case just update the CRC
298 **/
299static struct symbol *sym_add_exported(const char *name, struct module *mod,
300 enum export export)
301{
302 struct symbol *s = find_symbol(name);
303
304 if (!s) {
305 s = new_symbol(name, mod, export);
306 } else {
307 if (!s->preloaded) {
308 warn("%s: '%s' exported twice. Previous export "
309 "was in %s%s\n", mod->name, name,
310 s->module->name,
311 is_vmlinux(s->module->name) ?"":".ko");
312 } else {
313 /* In case Modules.symvers was out of date */
314 s->module = mod;
315 }
316 }
317 s->preloaded = 0;
318 s->vmlinux = is_vmlinux(mod->name);
319 s->kernel = 0;
320 s->export = export;
321 return s;
322}
323
324static void sym_update_crc(const char *name, struct module *mod,
325 unsigned int crc, enum export export)
326{
327 struct symbol *s = find_symbol(name);
328
329 if (!s)
330 s = new_symbol(name, mod, export);
331 s->crc = crc;
332 s->crc_valid = 1;
333}
334
335void *grab_file(const char *filename, unsigned long *size)
336{
337 struct stat st;
338 void *map;
339 int fd;
340
341 fd = open(filename, O_RDONLY);
342 if (fd < 0 || fstat(fd, &st) != 0)
343 return NULL;
344
345 *size = st.st_size;
346 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
347 close(fd);
348
349 if (map == MAP_FAILED)
350 return NULL;
351 return map;
352}
353
354/**
355 * Return a copy of the next line in a mmap'ed file.
356 * spaces in the beginning of the line is trimmed away.
357 * Return a pointer to a static buffer.
358 **/
359char *get_next_line(unsigned long *pos, void *file, unsigned long size)
360{
361 static char line[4096];
362 int skip = 1;
363 size_t len = 0;
364 signed char *p = (signed char *)file + *pos;
365 char *s = line;
366
367 for (; *pos < size ; (*pos)++) {
368 if (skip && isspace(*p)) {
369 p++;
370 continue;
371 }
372 skip = 0;
373 if (*p != '\n' && (*pos < size)) {
374 len++;
375 *s++ = *p++;
376 if (len > 4095)
377 break; /* Too long, stop */
378 } else {
379 /* End of string */
380 *s = '\0';
381 return line;
382 }
383 }
384 /* End of buffer */
385 return NULL;
386}
387
388void release_file(void *file, unsigned long size)
389{
390 munmap(file, size);
391}
392
393static int parse_elf(struct elf_info *info, const char *filename)
394{
395 unsigned int i;
396 Elf_Ehdr *hdr;
397 Elf_Shdr *sechdrs;
398 Elf_Sym *sym;
399 const char *secstrings;
400 unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
401
402 hdr = grab_file(filename, &info->size);
403 if (!hdr) {
404 perror(filename);
405 exit(1);
406 }
407 info->hdr = hdr;
408 if (info->size < sizeof(*hdr)) {
409 /* file too small, assume this is an empty .o file */
410 return 0;
411 }
412 /* Is this a valid ELF file? */
413 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
414 (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
415 (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
416 (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
417 /* Not an ELF file - silently ignore it */
418 return 0;
419 }
420 /* Fix endianness in ELF header */
421 hdr->e_type = TO_NATIVE(hdr->e_type);
422 hdr->e_machine = TO_NATIVE(hdr->e_machine);
423 hdr->e_version = TO_NATIVE(hdr->e_version);
424 hdr->e_entry = TO_NATIVE(hdr->e_entry);
425 hdr->e_phoff = TO_NATIVE(hdr->e_phoff);
426 hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
427 hdr->e_flags = TO_NATIVE(hdr->e_flags);
428 hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize);
429 hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
430 hdr->e_phnum = TO_NATIVE(hdr->e_phnum);
431 hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
432 hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
433 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
434 sechdrs = (void *)hdr + hdr->e_shoff;
435 info->sechdrs = sechdrs;
436
437 /* Check if file offset is correct */
438 if (hdr->e_shoff > info->size) {
439 fatal("section header offset=%lu in file '%s' is bigger than "
440 "filesize=%lu\n", (unsigned long)hdr->e_shoff,
441 filename, info->size);
442 return 0;
443 }
444
445 if (hdr->e_shnum == SHN_UNDEF) {
446 /*
447 * There are more than 64k sections,
448 * read count from .sh_size.
449 */
450 info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
451 }
452 else {
453 info->num_sections = hdr->e_shnum;
454 }
455 if (hdr->e_shstrndx == SHN_XINDEX) {
456 info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
457 }
458 else {
459 info->secindex_strings = hdr->e_shstrndx;
460 }
461
462 /* Fix endianness in section headers */
463 for (i = 0; i < info->num_sections; i++) {
464 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
465 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
466 sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
467 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
468 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
469 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
470 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
471 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
472 sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
473 sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
474 }
475 /* Find symbol table. */
476 secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
477 for (i = 1; i < info->num_sections; i++) {
478 const char *secname;
479 int nobits = sechdrs[i].sh_type == SHT_NOBITS;
480
481 if (!nobits && sechdrs[i].sh_offset > info->size) {
482 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
483 "sizeof(*hrd)=%zu\n", filename,
484 (unsigned long)sechdrs[i].sh_offset,
485 sizeof(*hdr));
486 return 0;
487 }
488 secname = secstrings + sechdrs[i].sh_name;
489 if (strcmp(secname, ".modinfo") == 0) {
490 if (nobits)
491 fatal("%s has NOBITS .modinfo\n", filename);
492 info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
493 info->modinfo_len = sechdrs[i].sh_size;
494 } else if (strcmp(secname, "__ksymtab") == 0)
495 info->export_sec = i;
496 else if (strcmp(secname, "__ksymtab_unused") == 0)
497 info->export_unused_sec = i;
498 else if (strcmp(secname, "__ksymtab_gpl") == 0)
499 info->export_gpl_sec = i;
500 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
501 info->export_unused_gpl_sec = i;
502 else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
503 info->export_gpl_future_sec = i;
504
505 if (sechdrs[i].sh_type == SHT_SYMTAB) {
506 unsigned int sh_link_idx;
507 symtab_idx = i;
508 info->symtab_start = (void *)hdr +
509 sechdrs[i].sh_offset;
510 info->symtab_stop = (void *)hdr +
511 sechdrs[i].sh_offset + sechdrs[i].sh_size;
512 sh_link_idx = sechdrs[i].sh_link;
513 info->strtab = (void *)hdr +
514 sechdrs[sh_link_idx].sh_offset;
515 }
516
517 /* 32bit section no. table? ("more than 64k sections") */
518 if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
519 symtab_shndx_idx = i;
520 info->symtab_shndx_start = (void *)hdr +
521 sechdrs[i].sh_offset;
522 info->symtab_shndx_stop = (void *)hdr +
523 sechdrs[i].sh_offset + sechdrs[i].sh_size;
524 }
525 }
526 if (!info->symtab_start)
527 fatal("%s has no symtab?\n", filename);
528
529 /* Fix endianness in symbols */
530 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
531 sym->st_shndx = TO_NATIVE(sym->st_shndx);
532 sym->st_name = TO_NATIVE(sym->st_name);
533 sym->st_value = TO_NATIVE(sym->st_value);
534 sym->st_size = TO_NATIVE(sym->st_size);
535 }
536
537 if (symtab_shndx_idx != ~0U) {
538 Elf32_Word *p;
539 if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
540 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
541 filename, sechdrs[symtab_shndx_idx].sh_link,
542 symtab_idx);
543 /* Fix endianness */
544 for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
545 p++)
546 *p = TO_NATIVE(*p);
547 }
548
549 return 1;
550}
551
552static void parse_elf_finish(struct elf_info *info)
553{
554 release_file(info->hdr, info->size);
555}
556
557static int ignore_undef_symbol(struct elf_info *info, const char *symname)
558{
559 /* ignore __this_module, it will be resolved shortly */
560 if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0)
561 return 1;
562 /* ignore global offset table */
563 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
564 return 1;
565 if (info->hdr->e_machine == EM_PPC)
566 /* Special register function linked on all modules during final link of .ko */
567 if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 ||
568 strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 ||
569 strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
570 strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0)
571 return 1;
572 if (info->hdr->e_machine == EM_PPC64)
573 /* Special register function linked on all modules during final link of .ko */
574 if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 ||
575 strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0)
576 return 1;
577 /* Do not ignore this symbol */
578 return 0;
579}
580
581#define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_"
582#define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
583
584static void handle_modversions(struct module *mod, struct elf_info *info,
585 Elf_Sym *sym, const char *symname)
586{
587 unsigned int crc;
588 enum export export;
589
590 if (!is_vmlinux(mod->name) && strncmp(symname, "__ksymtab", 9) == 0)
591 export = export_from_secname(info, get_secindex(info, sym));
592 else
593 export = export_from_sec(info, get_secindex(info, sym));
594
595 switch (sym->st_shndx) {
596 case SHN_COMMON:
597 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
598 break;
599 case SHN_ABS:
600 /* CRC'd symbol */
601 if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
602 crc = (unsigned int) sym->st_value;
603 sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
604 export);
605 }
606 break;
607 case SHN_UNDEF:
608 /* undefined symbol */
609 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
610 ELF_ST_BIND(sym->st_info) != STB_WEAK)
611 break;
612 if (ignore_undef_symbol(info, symname))
613 break;
614/* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
615#if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
616/* add compatibility with older glibc */
617#ifndef STT_SPARC_REGISTER
618#define STT_SPARC_REGISTER STT_REGISTER
619#endif
620 if (info->hdr->e_machine == EM_SPARC ||
621 info->hdr->e_machine == EM_SPARCV9) {
622 /* Ignore register directives. */
623 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
624 break;
625 if (symname[0] == '.') {
626 char *munged = strdup(symname);
627 munged[0] = '_';
628 munged[1] = toupper(munged[1]);
629 symname = munged;
630 }
631 }
632#endif
633
634 if (memcmp(symname, MODULE_SYMBOL_PREFIX,
635 strlen(MODULE_SYMBOL_PREFIX)) == 0) {
636 mod->unres =
637 alloc_symbol(symname +
638 strlen(MODULE_SYMBOL_PREFIX),
639 ELF_ST_BIND(sym->st_info) == STB_WEAK,
640 mod->unres);
641 }
642 break;
643 default:
644 /* All exported symbols */
645 if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
646 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
647 export);
648 }
649 if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
650 mod->has_init = 1;
651 if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0)
652 mod->has_cleanup = 1;
653 break;
654 }
655}
656
657/**
658 * Parse tag=value strings from .modinfo section
659 **/
660static char *next_string(char *string, unsigned long *secsize)
661{
662 /* Skip non-zero chars */
663 while (string[0]) {
664 string++;
665 if ((*secsize)-- <= 1)
666 return NULL;
667 }
668
669 /* Skip any zero padding. */
670 while (!string[0]) {
671 string++;
672 if ((*secsize)-- <= 1)
673 return NULL;
674 }
675 return string;
676}
677
678static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
679 const char *tag, char *info)
680{
681 char *p;
682 unsigned int taglen = strlen(tag);
683 unsigned long size = modinfo_len;
684
685 if (info) {
686 size -= info - (char *)modinfo;
687 modinfo = next_string(info, &size);
688 }
689
690 for (p = modinfo; p; p = next_string(p, &size)) {
691 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
692 return p + taglen + 1;
693 }
694 return NULL;
695}
696
697static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
698 const char *tag)
699
700{
701 return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
702}
703
704/**
705 * Test if string s ends in string sub
706 * return 0 if match
707 **/
708static int strrcmp(const char *s, const char *sub)
709{
710 int slen, sublen;
711
712 if (!s || !sub)
713 return 1;
714
715 slen = strlen(s);
716 sublen = strlen(sub);
717
718 if ((slen == 0) || (sublen == 0))
719 return 1;
720
721 if (sublen > slen)
722 return 1;
723
724 return memcmp(s + slen - sublen, sub, sublen);
725}
726
727static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
728{
729 if (sym)
730 return elf->strtab + sym->st_name;
731 else
732 return "(unknown)";
733}
734
735static const char *sec_name(struct elf_info *elf, int secindex)
736{
737 Elf_Shdr *sechdrs = elf->sechdrs;
738 return (void *)elf->hdr +
739 elf->sechdrs[elf->secindex_strings].sh_offset +
740 sechdrs[secindex].sh_name;
741}
742
743static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr)
744{
745 return (void *)elf->hdr +
746 elf->sechdrs[elf->secindex_strings].sh_offset +
747 sechdr->sh_name;
748}
749
750/* if sym is empty or point to a string
751 * like ".[0-9]+" then return 1.
752 * This is the optional prefix added by ld to some sections
753 */
754static int number_prefix(const char *sym)
755{
756 if (*sym++ == '\0')
757 return 1;
758 if (*sym != '.')
759 return 0;
760 do {
761 char c = *sym++;
762 if (c < '0' || c > '9')
763 return 0;
764 } while (*sym);
765 return 1;
766}
767
768/* The pattern is an array of simple patterns.
769 * "foo" will match an exact string equal to "foo"
770 * "*foo" will match a string that ends with "foo"
771 * "foo*" will match a string that begins with "foo"
772 * "foo$" will match a string equal to "foo" or "foo.1"
773 * where the '1' can be any number including several digits.
774 * The $ syntax is for sections where ld append a dot number
775 * to make section name unique.
776 */
777static int match(const char *sym, const char * const pat[])
778{
779 const char *p;
780 while (*pat) {
781 p = *pat++;
782 const char *endp = p + strlen(p) - 1;
783
784 /* "*foo" */
785 if (*p == '*') {
786 if (strrcmp(sym, p + 1) == 0)
787 return 1;
788 }
789 /* "foo*" */
790 else if (*endp == '*') {
791 if (strncmp(sym, p, strlen(p) - 1) == 0)
792 return 1;
793 }
794 /* "foo$" */
795 else if (*endp == '$') {
796 if (strncmp(sym, p, strlen(p) - 1) == 0) {
797 if (number_prefix(sym + strlen(p) - 1))
798 return 1;
799 }
800 }
801 /* no wildcards */
802 else {
803 if (strcmp(p, sym) == 0)
804 return 1;
805 }
806 }
807 /* no match */
808 return 0;
809}
810
811/* sections that we do not want to do full section mismatch check on */
812static const char *section_white_list[] =
813{
814 ".comment*",
815 ".debug*",
816 ".zdebug*", /* Compressed debug sections. */
817 ".GCC-command-line", /* mn10300 */
818 ".mdebug*", /* alpha, score, mips etc. */
819 ".pdr", /* alpha, score, mips etc. */
820 ".stab*",
821 ".note*",
822 ".got*",
823 ".toc*",
824 NULL
825};
826
827/*
828 * This is used to find sections missing the SHF_ALLOC flag.
829 * The cause of this is often a section specified in assembler
830 * without "ax" / "aw".
831 */
832static void check_section(const char *modname, struct elf_info *elf,
833 Elf_Shdr *sechdr)
834{
835 const char *sec = sech_name(elf, sechdr);
836
837 if (sechdr->sh_type == SHT_PROGBITS &&
838 !(sechdr->sh_flags & SHF_ALLOC) &&
839 !match(sec, section_white_list)) {
840 warn("%s (%s): unexpected non-allocatable section.\n"
841 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
842 "Note that for example <linux/init.h> contains\n"
843 "section definitions for use in .S files.\n\n",
844 modname, sec);
845 }
846}
847
848
849
850#define ALL_INIT_DATA_SECTIONS \
851 ".init.setup$", ".init.rodata$", \
852 ".devinit.rodata$", ".cpuinit.rodata$", ".meminit.rodata$" \
853 ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$"
854#define ALL_EXIT_DATA_SECTIONS \
855 ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$"
856
857#define ALL_INIT_TEXT_SECTIONS \
858 ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$"
859#define ALL_EXIT_TEXT_SECTIONS \
860 ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$"
861
862#define ALL_XXXINIT_SECTIONS DEV_INIT_SECTIONS, CPU_INIT_SECTIONS, \
863 MEM_INIT_SECTIONS
864#define ALL_XXXEXIT_SECTIONS DEV_EXIT_SECTIONS, CPU_EXIT_SECTIONS, \
865 MEM_EXIT_SECTIONS
866
867#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
868#define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
869
870#define DATA_SECTIONS ".data$", ".data.rel$"
871#define TEXT_SECTIONS ".text$"
872
873#define INIT_SECTIONS ".init.*"
874#define DEV_INIT_SECTIONS ".devinit.*"
875#define CPU_INIT_SECTIONS ".cpuinit.*"
876#define MEM_INIT_SECTIONS ".meminit.*"
877
878#define EXIT_SECTIONS ".exit.*"
879#define DEV_EXIT_SECTIONS ".devexit.*"
880#define CPU_EXIT_SECTIONS ".cpuexit.*"
881#define MEM_EXIT_SECTIONS ".memexit.*"
882
883/* init data sections */
884static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL };
885
886/* all init sections */
887static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL };
888
889/* All init and exit sections (code + data) */
890static const char *init_exit_sections[] =
891 {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
892
893/* data section */
894static const char *data_sections[] = { DATA_SECTIONS, NULL };
895
896
897/* symbols in .data that may refer to init/exit sections */
898#define DEFAULT_SYMBOL_WHITE_LIST \
899 "*driver", \
900 "*_template", /* scsi uses *_template a lot */ \
901 "*_timer", /* arm uses ops structures named _timer a lot */ \
902 "*_sht", /* scsi also used *_sht to some extent */ \
903 "*_ops", \
904 "*_probe", \
905 "*_probe_one", \
906 "*_console"
907
908static const char *head_sections[] = { ".head.text*", NULL };
909static const char *linker_symbols[] =
910 { "__init_begin", "_sinittext", "_einittext", NULL };
911
912enum mismatch {
913 TEXT_TO_ANY_INIT,
914 DATA_TO_ANY_INIT,
915 TEXT_TO_ANY_EXIT,
916 DATA_TO_ANY_EXIT,
917 XXXINIT_TO_SOME_INIT,
918 XXXEXIT_TO_SOME_EXIT,
919 ANY_INIT_TO_ANY_EXIT,
920 ANY_EXIT_TO_ANY_INIT,
921 EXPORT_TO_INIT_EXIT,
922};
923
924struct sectioncheck {
925 const char *fromsec[20];
926 const char *tosec[20];
927 enum mismatch mismatch;
928 const char *symbol_white_list[20];
929};
930
931const struct sectioncheck sectioncheck[] = {
932/* Do not reference init/exit code/data from
933 * normal code and data
934 */
935{
936 .fromsec = { TEXT_SECTIONS, NULL },
937 .tosec = { ALL_INIT_SECTIONS, NULL },
938 .mismatch = TEXT_TO_ANY_INIT,
939 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
940},
941{
942 .fromsec = { DATA_SECTIONS, NULL },
943 .tosec = { ALL_XXXINIT_SECTIONS, NULL },
944 .mismatch = DATA_TO_ANY_INIT,
945 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
946},
947{
948 .fromsec = { DATA_SECTIONS, NULL },
949 .tosec = { INIT_SECTIONS, NULL },
950 .mismatch = DATA_TO_ANY_INIT,
951 .symbol_white_list = {
952 "*_template", "*_timer", "*_sht", "*_ops",
953 "*_probe", "*_probe_one", "*_console", NULL
954 },
955},
956{
957 .fromsec = { TEXT_SECTIONS, NULL },
958 .tosec = { ALL_EXIT_SECTIONS, NULL },
959 .mismatch = TEXT_TO_ANY_EXIT,
960 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
961},
962{
963 .fromsec = { DATA_SECTIONS, NULL },
964 .tosec = { ALL_EXIT_SECTIONS, NULL },
965 .mismatch = DATA_TO_ANY_EXIT,
966 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
967},
968/* Do not reference init code/data from devinit/cpuinit/meminit code/data */
969{
970 .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
971 .tosec = { INIT_SECTIONS, NULL },
972 .mismatch = XXXINIT_TO_SOME_INIT,
973 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
974},
975/* Do not reference cpuinit code/data from meminit code/data */
976{
977 .fromsec = { MEM_INIT_SECTIONS, NULL },
978 .tosec = { CPU_INIT_SECTIONS, NULL },
979 .mismatch = XXXINIT_TO_SOME_INIT,
980 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
981},
982/* Do not reference meminit code/data from cpuinit code/data */
983{
984 .fromsec = { CPU_INIT_SECTIONS, NULL },
985 .tosec = { MEM_INIT_SECTIONS, NULL },
986 .mismatch = XXXINIT_TO_SOME_INIT,
987 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
988},
989/* Do not reference exit code/data from devexit/cpuexit/memexit code/data */
990{
991 .fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
992 .tosec = { EXIT_SECTIONS, NULL },
993 .mismatch = XXXEXIT_TO_SOME_EXIT,
994 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
995},
996/* Do not reference cpuexit code/data from memexit code/data */
997{
998 .fromsec = { MEM_EXIT_SECTIONS, NULL },
999 .tosec = { CPU_EXIT_SECTIONS, NULL },
1000 .mismatch = XXXEXIT_TO_SOME_EXIT,
1001 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1002},
1003/* Do not reference memexit code/data from cpuexit code/data */
1004{
1005 .fromsec = { CPU_EXIT_SECTIONS, NULL },
1006 .tosec = { MEM_EXIT_SECTIONS, NULL },
1007 .mismatch = XXXEXIT_TO_SOME_EXIT,
1008 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1009},
1010/* Do not use exit code/data from init code */
1011{
1012 .fromsec = { ALL_INIT_SECTIONS, NULL },
1013 .tosec = { ALL_EXIT_SECTIONS, NULL },
1014 .mismatch = ANY_INIT_TO_ANY_EXIT,
1015 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1016},
1017/* Do not use init code/data from exit code */
1018{
1019 .fromsec = { ALL_EXIT_SECTIONS, NULL },
1020 .tosec = { ALL_INIT_SECTIONS, NULL },
1021 .mismatch = ANY_EXIT_TO_ANY_INIT,
1022 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1023},
1024/* Do not export init/exit functions or data */
1025{
1026 .fromsec = { "__ksymtab*", NULL },
1027 .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
1028 .mismatch = EXPORT_TO_INIT_EXIT,
1029 .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
1030}
1031};
1032
1033static const struct sectioncheck *section_mismatch(
1034 const char *fromsec, const char *tosec)
1035{
1036 int i;
1037 int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
1038 const struct sectioncheck *check = §ioncheck[0];
1039
1040 for (i = 0; i < elems; i++) {
1041 if (match(fromsec, check->fromsec) &&
1042 match(tosec, check->tosec))
1043 return check;
1044 check++;
1045 }
1046 return NULL;
1047}
1048
1049/**
1050 * Whitelist to allow certain references to pass with no warning.
1051 *
1052 * Pattern 1:
1053 * If a module parameter is declared __initdata and permissions=0
1054 * then this is legal despite the warning generated.
1055 * We cannot see value of permissions here, so just ignore
1056 * this pattern.
1057 * The pattern is identified by:
1058 * tosec = .init.data
1059 * fromsec = .data*
1060 * atsym =__param*
1061 *
1062 * Pattern 1a:
1063 * module_param_call() ops can refer to __init set function if permissions=0
1064 * The pattern is identified by:
1065 * tosec = .init.text
1066 * fromsec = .data*
1067 * atsym = __param_ops_*
1068 *
1069 * Pattern 2:
1070 * Many drivers utilise a *driver container with references to
1071 * add, remove, probe functions etc.
1072 * These functions may often be marked __devinit and we do not want to
1073 * warn here.
1074 * the pattern is identified by:
1075 * tosec = init or exit section
1076 * fromsec = data section
1077 * atsym = *driver, *_template, *_sht, *_ops, *_probe,
1078 * *probe_one, *_console, *_timer
1079 *
1080 * Pattern 3:
1081 * Whitelist all references from .head.text to any init section
1082 *
1083 * Pattern 4:
1084 * Some symbols belong to init section but still it is ok to reference
1085 * these from non-init sections as these symbols don't have any memory
1086 * allocated for them and symbol address and value are same. So even
1087 * if init section is freed, its ok to reference those symbols.
1088 * For ex. symbols marking the init section boundaries.
1089 * This pattern is identified by
1090 * refsymname = __init_begin, _sinittext, _einittext
1091 *
1092 **/
1093static int secref_whitelist(const struct sectioncheck *mismatch,
1094 const char *fromsec, const char *fromsym,
1095 const char *tosec, const char *tosym)
1096{
1097 /* Check for pattern 1 */
1098 if (match(tosec, init_data_sections) &&
1099 match(fromsec, data_sections) &&
1100 (strncmp(fromsym, "__param", strlen("__param")) == 0))
1101 return 0;
1102
1103 /* Check for pattern 1a */
1104 if (strcmp(tosec, ".init.text") == 0 &&
1105 match(fromsec, data_sections) &&
1106 (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0))
1107 return 0;
1108
1109 /* Check for pattern 2 */
1110 if (match(tosec, init_exit_sections) &&
1111 match(fromsec, data_sections) &&
1112 match(fromsym, mismatch->symbol_white_list))
1113 return 0;
1114
1115 /* Check for pattern 3 */
1116 if (match(fromsec, head_sections) &&
1117 match(tosec, init_sections))
1118 return 0;
1119
1120 /* Check for pattern 4 */
1121 if (match(tosym, linker_symbols))
1122 return 0;
1123
1124 return 1;
1125}
1126
1127/**
1128 * Find symbol based on relocation record info.
1129 * In some cases the symbol supplied is a valid symbol so
1130 * return refsym. If st_name != 0 we assume this is a valid symbol.
1131 * In other cases the symbol needs to be looked up in the symbol table
1132 * based on section and address.
1133 * **/
1134static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
1135 Elf_Sym *relsym)
1136{
1137 Elf_Sym *sym;
1138 Elf_Sym *near = NULL;
1139 Elf64_Sword distance = 20;
1140 Elf64_Sword d;
1141 unsigned int relsym_secindex;
1142
1143 if (relsym->st_name != 0)
1144 return relsym;
1145
1146 relsym_secindex = get_secindex(elf, relsym);
1147 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1148 if (get_secindex(elf, sym) != relsym_secindex)
1149 continue;
1150 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
1151 continue;
1152 if (sym->st_value == addr)
1153 return sym;
1154 /* Find a symbol nearby - addr are maybe negative */
1155 d = sym->st_value - addr;
1156 if (d < 0)
1157 d = addr - sym->st_value;
1158 if (d < distance) {
1159 distance = d;
1160 near = sym;
1161 }
1162 }
1163 /* We need a close match */
1164 if (distance < 20)
1165 return near;
1166 else
1167 return NULL;
1168}
1169
1170static inline int is_arm_mapping_symbol(const char *str)
1171{
1172 return str[0] == '$' && strchr("atd", str[1])
1173 && (str[2] == '\0' || str[2] == '.');
1174}
1175
1176/*
1177 * If there's no name there, ignore it; likewise, ignore it if it's
1178 * one of the magic symbols emitted used by current ARM tools.
1179 *
1180 * Otherwise if find_symbols_between() returns those symbols, they'll
1181 * fail the whitelist tests and cause lots of false alarms ... fixable
1182 * only by merging __exit and __init sections into __text, bloating
1183 * the kernel (which is especially evil on embedded platforms).
1184 */
1185static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
1186{
1187 const char *name = elf->strtab + sym->st_name;
1188
1189 if (!name || !strlen(name))
1190 return 0;
1191 return !is_arm_mapping_symbol(name);
1192}
1193
1194/*
1195 * Find symbols before or equal addr and after addr - in the section sec.
1196 * If we find two symbols with equal offset prefer one with a valid name.
1197 * The ELF format may have a better way to detect what type of symbol
1198 * it is, but this works for now.
1199 **/
1200static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
1201 const char *sec)
1202{
1203 Elf_Sym *sym;
1204 Elf_Sym *near = NULL;
1205 Elf_Addr distance = ~0;
1206
1207 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
1208 const char *symsec;
1209
1210 if (is_shndx_special(sym->st_shndx))
1211 continue;
1212 symsec = sec_name(elf, get_secindex(elf, sym));
1213 if (strcmp(symsec, sec) != 0)
1214 continue;
1215 if (!is_valid_name(elf, sym))
1216 continue;
1217 if (sym->st_value <= addr) {
1218 if ((addr - sym->st_value) < distance) {
1219 distance = addr - sym->st_value;
1220 near = sym;
1221 } else if ((addr - sym->st_value) == distance) {
1222 near = sym;
1223 }
1224 }
1225 }
1226 return near;
1227}
1228
1229/*
1230 * Convert a section name to the function/data attribute
1231 * .init.text => __init
1232 * .cpuinit.data => __cpudata
1233 * .memexitconst => __memconst
1234 * etc.
1235 *
1236 * The memory of returned value has been allocated on a heap. The user of this
1237 * method should free it after usage.
1238*/
1239static char *sec2annotation(const char *s)
1240{
1241 if (match(s, init_exit_sections)) {
1242 char *p = malloc(20);
1243 char *r = p;
1244
1245 *p++ = '_';
1246 *p++ = '_';
1247 if (*s == '.')
1248 s++;
1249 while (*s && *s != '.')
1250 *p++ = *s++;
1251 *p = '\0';
1252 if (*s == '.')
1253 s++;
1254 if (strstr(s, "rodata") != NULL)
1255 strcat(p, "const ");
1256 else if (strstr(s, "data") != NULL)
1257 strcat(p, "data ");
1258 else
1259 strcat(p, " ");
1260 return r;
1261 } else {
1262 return strdup("");
1263 }
1264}
1265
1266static int is_function(Elf_Sym *sym)
1267{
1268 if (sym)
1269 return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
1270 else
1271 return -1;
1272}
1273
1274static void print_section_list(const char * const list[20])
1275{
1276 const char *const *s = list;
1277
1278 while (*s) {
1279 fprintf(stderr, "%s", *s);
1280 s++;
1281 if (*s)
1282 fprintf(stderr, ", ");
1283 }
1284 fprintf(stderr, "\n");
1285}
1286
1287/*
1288 * Print a warning about a section mismatch.
1289 * Try to find symbols near it so user can find it.
1290 * Check whitelist before warning - it may be a false positive.
1291 */
1292static void report_sec_mismatch(const char *modname,
1293 const struct sectioncheck *mismatch,
1294 const char *fromsec,
1295 unsigned long long fromaddr,
1296 const char *fromsym,
1297 int from_is_func,
1298 const char *tosec, const char *tosym,
1299 int to_is_func)
1300{
1301 const char *from, *from_p;
1302 const char *to, *to_p;
1303 char *prl_from;
1304 char *prl_to;
1305
1306 switch (from_is_func) {
1307 case 0: from = "variable"; from_p = ""; break;
1308 case 1: from = "function"; from_p = "()"; break;
1309 default: from = "(unknown reference)"; from_p = ""; break;
1310 }
1311 switch (to_is_func) {
1312 case 0: to = "variable"; to_p = ""; break;
1313 case 1: to = "function"; to_p = "()"; break;
1314 default: to = "(unknown reference)"; to_p = ""; break;
1315 }
1316
1317 sec_mismatch_count++;
1318 if (!sec_mismatch_verbose)
1319 return;
1320
1321 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1322 "to the %s %s:%s%s\n",
1323 modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
1324 tosym, to_p);
1325
1326 switch (mismatch->mismatch) {
1327 case TEXT_TO_ANY_INIT:
1328 prl_from = sec2annotation(fromsec);
1329 prl_to = sec2annotation(tosec);
1330 fprintf(stderr,
1331 "The function %s%s() references\n"
1332 "the %s %s%s%s.\n"
1333 "This is often because %s lacks a %s\n"
1334 "annotation or the annotation of %s is wrong.\n",
1335 prl_from, fromsym,
1336 to, prl_to, tosym, to_p,
1337 fromsym, prl_to, tosym);
1338 free(prl_from);
1339 free(prl_to);
1340 break;
1341 case DATA_TO_ANY_INIT: {
1342 prl_to = sec2annotation(tosec);
1343 fprintf(stderr,
1344 "The variable %s references\n"
1345 "the %s %s%s%s\n"
1346 "If the reference is valid then annotate the\n"
1347 "variable with __init* or __refdata (see linux/init.h) "
1348 "or name the variable:\n",
1349 fromsym, to, prl_to, tosym, to_p);
1350 print_section_list(mismatch->symbol_white_list);
1351 free(prl_to);
1352 break;
1353 }
1354 case TEXT_TO_ANY_EXIT:
1355 prl_to = sec2annotation(tosec);
1356 fprintf(stderr,
1357 "The function %s() references a %s in an exit section.\n"
1358 "Often the %s %s%s has valid usage outside the exit section\n"
1359 "and the fix is to remove the %sannotation of %s.\n",
1360 fromsym, to, to, tosym, to_p, prl_to, tosym);
1361 free(prl_to);
1362 break;
1363 case DATA_TO_ANY_EXIT: {
1364 prl_to = sec2annotation(tosec);
1365 fprintf(stderr,
1366 "The variable %s references\n"
1367 "the %s %s%s%s\n"
1368 "If the reference is valid then annotate the\n"
1369 "variable with __exit* (see linux/init.h) or "
1370 "name the variable:\n",
1371 fromsym, to, prl_to, tosym, to_p);
1372 print_section_list(mismatch->symbol_white_list);
1373 free(prl_to);
1374 break;
1375 }
1376 case XXXINIT_TO_SOME_INIT:
1377 case XXXEXIT_TO_SOME_EXIT:
1378 prl_from = sec2annotation(fromsec);
1379 prl_to = sec2annotation(tosec);
1380 fprintf(stderr,
1381 "The %s %s%s%s references\n"
1382 "a %s %s%s%s.\n"
1383 "If %s is only used by %s then\n"
1384 "annotate %s with a matching annotation.\n",
1385 from, prl_from, fromsym, from_p,
1386 to, prl_to, tosym, to_p,
1387 tosym, fromsym, tosym);
1388 free(prl_from);
1389 free(prl_to);
1390 break;
1391 case ANY_INIT_TO_ANY_EXIT:
1392 prl_from = sec2annotation(fromsec);
1393 prl_to = sec2annotation(tosec);
1394 fprintf(stderr,
1395 "The %s %s%s%s references\n"
1396 "a %s %s%s%s.\n"
1397 "This is often seen when error handling "
1398 "in the init function\n"
1399 "uses functionality in the exit path.\n"
1400 "The fix is often to remove the %sannotation of\n"
1401 "%s%s so it may be used outside an exit section.\n",
1402 from, prl_from, fromsym, from_p,
1403 to, prl_to, tosym, to_p,
1404 prl_to, tosym, to_p);
1405 free(prl_from);
1406 free(prl_to);
1407 break;
1408 case ANY_EXIT_TO_ANY_INIT:
1409 prl_from = sec2annotation(fromsec);
1410 prl_to = sec2annotation(tosec);
1411 fprintf(stderr,
1412 "The %s %s%s%s references\n"
1413 "a %s %s%s%s.\n"
1414 "This is often seen when error handling "
1415 "in the exit function\n"
1416 "uses functionality in the init path.\n"
1417 "The fix is often to remove the %sannotation of\n"
1418 "%s%s so it may be used outside an init section.\n",
1419 from, prl_from, fromsym, from_p,
1420 to, prl_to, tosym, to_p,
1421 prl_to, tosym, to_p);
1422 free(prl_from);
1423 free(prl_to);
1424 break;
1425 case EXPORT_TO_INIT_EXIT:
1426 prl_to = sec2annotation(tosec);
1427 fprintf(stderr,
1428 "The symbol %s is exported and annotated %s\n"
1429 "Fix this by removing the %sannotation of %s "
1430 "or drop the export.\n",
1431 tosym, prl_to, prl_to, tosym);
1432 free(prl_to);
1433 break;
1434 }
1435 fprintf(stderr, "\n");
1436}
1437
1438static void check_section_mismatch(const char *modname, struct elf_info *elf,
1439 Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
1440{
1441 const char *tosec;
1442 const struct sectioncheck *mismatch;
1443
1444 tosec = sec_name(elf, get_secindex(elf, sym));
1445 mismatch = section_mismatch(fromsec, tosec);
1446 if (mismatch) {
1447 Elf_Sym *to;
1448 Elf_Sym *from;
1449 const char *tosym;
1450 const char *fromsym;
1451
1452 from = find_elf_symbol2(elf, r->r_offset, fromsec);
1453 fromsym = sym_name(elf, from);
1454 to = find_elf_symbol(elf, r->r_addend, sym);
1455 tosym = sym_name(elf, to);
1456
1457 /* check whitelist - we may ignore it */
1458 if (secref_whitelist(mismatch,
1459 fromsec, fromsym, tosec, tosym)) {
1460 report_sec_mismatch(modname, mismatch,
1461 fromsec, r->r_offset, fromsym,
1462 is_function(from), tosec, tosym,
1463 is_function(to));
1464 }
1465 }
1466}
1467
1468static unsigned int *reloc_location(struct elf_info *elf,
1469 Elf_Shdr *sechdr, Elf_Rela *r)
1470{
1471 Elf_Shdr *sechdrs = elf->sechdrs;
1472 int section = sechdr->sh_info;
1473
1474 return (void *)elf->hdr + sechdrs[section].sh_offset +
1475 r->r_offset;
1476}
1477
1478static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1479{
1480 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1481 unsigned int *location = reloc_location(elf, sechdr, r);
1482
1483 switch (r_typ) {
1484 case R_386_32:
1485 r->r_addend = TO_NATIVE(*location);
1486 break;
1487 case R_386_PC32:
1488 r->r_addend = TO_NATIVE(*location) + 4;
1489 /* For CONFIG_RELOCATABLE=y */
1490 if (elf->hdr->e_type == ET_EXEC)
1491 r->r_addend += r->r_offset;
1492 break;
1493 }
1494 return 0;
1495}
1496
1497static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1498{
1499 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1500
1501 switch (r_typ) {
1502 case R_ARM_ABS32:
1503 /* From ARM ABI: (S + A) | T */
1504 r->r_addend = (int)(long)
1505 (elf->symtab_start + ELF_R_SYM(r->r_info));
1506 break;
1507 case R_ARM_PC24:
1508 /* From ARM ABI: ((S + A) | T) - P */
1509 r->r_addend = (int)(long)(elf->hdr +
1510 sechdr->sh_offset +
1511 (r->r_offset - sechdr->sh_addr));
1512 break;
1513 default:
1514 return 1;
1515 }
1516 return 0;
1517}
1518
1519static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
1520{
1521 unsigned int r_typ = ELF_R_TYPE(r->r_info);
1522 unsigned int *location = reloc_location(elf, sechdr, r);
1523 unsigned int inst;
1524
1525 if (r_typ == R_MIPS_HI16)
1526 return 1; /* skip this */
1527 inst = TO_NATIVE(*location);
1528 switch (r_typ) {
1529 case R_MIPS_LO16:
1530 r->r_addend = inst & 0xffff;
1531 break;
1532 case R_MIPS_26:
1533 r->r_addend = (inst & 0x03ffffff) << 2;
1534 break;
1535 case R_MIPS_32:
1536 r->r_addend = inst;
1537 break;
1538 }
1539 return 0;
1540}
1541
1542static void section_rela(const char *modname, struct elf_info *elf,
1543 Elf_Shdr *sechdr)
1544{
1545 Elf_Sym *sym;
1546 Elf_Rela *rela;
1547 Elf_Rela r;
1548 unsigned int r_sym;
1549 const char *fromsec;
1550
1551 Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
1552 Elf_Rela *stop = (void *)start + sechdr->sh_size;
1553
1554 fromsec = sech_name(elf, sechdr);
1555 fromsec += strlen(".rela");
1556 /* if from section (name) is know good then skip it */
1557 if (match(fromsec, section_white_list))
1558 return;
1559
1560 for (rela = start; rela < stop; rela++) {
1561 r.r_offset = TO_NATIVE(rela->r_offset);
1562#if KERNEL_ELFCLASS == ELFCLASS64
1563 if (elf->hdr->e_machine == EM_MIPS) {
1564 unsigned int r_typ;
1565 r_sym = ELF64_MIPS_R_SYM(rela->r_info);
1566 r_sym = TO_NATIVE(r_sym);
1567 r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
1568 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1569 } else {
1570 r.r_info = TO_NATIVE(rela->r_info);
1571 r_sym = ELF_R_SYM(r.r_info);
1572 }
1573#else
1574 r.r_info = TO_NATIVE(rela->r_info);
1575 r_sym = ELF_R_SYM(r.r_info);
1576#endif
1577 r.r_addend = TO_NATIVE(rela->r_addend);
1578 sym = elf->symtab_start + r_sym;
1579 /* Skip special sections */
1580 if (is_shndx_special(sym->st_shndx))
1581 continue;
1582 check_section_mismatch(modname, elf, &r, sym, fromsec);
1583 }
1584}
1585
1586static void section_rel(const char *modname, struct elf_info *elf,
1587 Elf_Shdr *sechdr)
1588{
1589 Elf_Sym *sym;
1590 Elf_Rel *rel;
1591 Elf_Rela r;
1592 unsigned int r_sym;
1593 const char *fromsec;
1594
1595 Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
1596 Elf_Rel *stop = (void *)start + sechdr->sh_size;
1597
1598 fromsec = sech_name(elf, sechdr);
1599 fromsec += strlen(".rel");
1600 /* if from section (name) is know good then skip it */
1601 if (match(fromsec, section_white_list))
1602 return;
1603
1604 for (rel = start; rel < stop; rel++) {
1605 r.r_offset = TO_NATIVE(rel->r_offset);
1606#if KERNEL_ELFCLASS == ELFCLASS64
1607 if (elf->hdr->e_machine == EM_MIPS) {
1608 unsigned int r_typ;
1609 r_sym = ELF64_MIPS_R_SYM(rel->r_info);
1610 r_sym = TO_NATIVE(r_sym);
1611 r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
1612 r.r_info = ELF64_R_INFO(r_sym, r_typ);
1613 } else {
1614 r.r_info = TO_NATIVE(rel->r_info);
1615 r_sym = ELF_R_SYM(r.r_info);
1616 }
1617#else
1618 r.r_info = TO_NATIVE(rel->r_info);
1619 r_sym = ELF_R_SYM(r.r_info);
1620#endif
1621 r.r_addend = 0;
1622 switch (elf->hdr->e_machine) {
1623 case EM_386:
1624 if (addend_386_rel(elf, sechdr, &r))
1625 continue;
1626 break;
1627 case EM_ARM:
1628 if (addend_arm_rel(elf, sechdr, &r))
1629 continue;
1630 break;
1631 case EM_MIPS:
1632 if (addend_mips_rel(elf, sechdr, &r))
1633 continue;
1634 break;
1635 }
1636 sym = elf->symtab_start + r_sym;
1637 /* Skip special sections */
1638 if (is_shndx_special(sym->st_shndx))
1639 continue;
1640 check_section_mismatch(modname, elf, &r, sym, fromsec);
1641 }
1642}
1643
1644/**
1645 * A module includes a number of sections that are discarded
1646 * either when loaded or when used as built-in.
1647 * For loaded modules all functions marked __init and all data
1648 * marked __initdata will be discarded when the module has been initialized.
1649 * Likewise for modules used built-in the sections marked __exit
1650 * are discarded because __exit marked function are supposed to be called
1651 * only when a module is unloaded which never happens for built-in modules.
1652 * The check_sec_ref() function traverses all relocation records
1653 * to find all references to a section that reference a section that will
1654 * be discarded and warns about it.
1655 **/
1656static void check_sec_ref(struct module *mod, const char *modname,
1657 struct elf_info *elf)
1658{
1659 int i;
1660 Elf_Shdr *sechdrs = elf->sechdrs;
1661
1662 /* Walk through all sections */
1663 for (i = 0; i < elf->num_sections; i++) {
1664 check_section(modname, elf, &elf->sechdrs[i]);
1665 /* We want to process only relocation sections and not .init */
1666 if (sechdrs[i].sh_type == SHT_RELA)
1667 section_rela(modname, elf, &elf->sechdrs[i]);
1668 else if (sechdrs[i].sh_type == SHT_REL)
1669 section_rel(modname, elf, &elf->sechdrs[i]);
1670 }
1671}
1672
1673static void read_symbols(char *modname)
1674{
1675 const char *symname;
1676 char *version;
1677 char *license;
1678 struct module *mod;
1679 struct elf_info info = { };
1680 Elf_Sym *sym;
1681
1682 if (!parse_elf(&info, modname))
1683 return;
1684
1685 mod = new_module(modname);
1686
1687 /* When there's no vmlinux, don't print warnings about
1688 * unresolved symbols (since there'll be too many ;) */
1689 if (is_vmlinux(modname)) {
1690 have_vmlinux = 1;
1691 mod->skip = 1;
1692 }
1693
1694 license = get_modinfo(info.modinfo, info.modinfo_len, "license");
1695 if (info.modinfo && !license && !is_vmlinux(modname))
1696 warn("modpost: missing MODULE_LICENSE() in %s\n"
1697 "see include/linux/module.h for "
1698 "more information\n", modname);
1699 while (license) {
1700 if (license_is_gpl_compatible(license))
1701 mod->gpl_compatible = 1;
1702 else {
1703 mod->gpl_compatible = 0;
1704 break;
1705 }
1706 license = get_next_modinfo(info.modinfo, info.modinfo_len,
1707 "license", license);
1708 }
1709
1710 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
1711 symname = info.strtab + sym->st_name;
1712
1713 handle_modversions(mod, &info, sym, symname);
1714 handle_moddevtable(mod, &info, sym, symname);
1715 }
1716 if (!is_vmlinux(modname) ||
1717 (is_vmlinux(modname) && vmlinux_section_warnings))
1718 check_sec_ref(mod, modname, &info);
1719
1720 version = get_modinfo(info.modinfo, info.modinfo_len, "version");
1721 if (version)
1722 maybe_frob_rcs_version(modname, version, info.modinfo,
1723 version - (char *)info.hdr);
1724 if (version || (all_versions && !is_vmlinux(modname)))
1725 get_src_version(modname, mod->srcversion,
1726 sizeof(mod->srcversion)-1);
1727
1728 parse_elf_finish(&info);
1729
1730 /* Our trick to get versioning for module struct etc. - it's
1731 * never passed as an argument to an exported function, so
1732 * the automatic versioning doesn't pick it up, but it's really
1733 * important anyhow */
1734 if (modversions)
1735 mod->unres = alloc_symbol("module_layout", 0, mod->unres);
1736}
1737
1738#define SZ 500
1739
1740/* We first write the generated file into memory using the
1741 * following helper, then compare to the file on disk and
1742 * only update the later if anything changed */
1743
1744void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
1745 const char *fmt, ...)
1746{
1747 char tmp[SZ];
1748 int len;
1749 va_list ap;
1750
1751 va_start(ap, fmt);
1752 len = vsnprintf(tmp, SZ, fmt, ap);
1753 buf_write(buf, tmp, len);
1754 va_end(ap);
1755}
1756
1757void buf_write(struct buffer *buf, const char *s, int len)
1758{
1759 if (buf->size - buf->pos < len) {
1760 buf->size += len + SZ;
1761 buf->p = realloc(buf->p, buf->size);
1762 }
1763 strncpy(buf->p + buf->pos, s, len);
1764 buf->pos += len;
1765}
1766
1767static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
1768{
1769 const char *e = is_vmlinux(m) ?"":".ko";
1770
1771 switch (exp) {
1772 case export_gpl:
1773 fatal("modpost: GPL-incompatible module %s%s "
1774 "uses GPL-only symbol '%s'\n", m, e, s);
1775 break;
1776 case export_unused_gpl:
1777 fatal("modpost: GPL-incompatible module %s%s "
1778 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
1779 break;
1780 case export_gpl_future:
1781 warn("modpost: GPL-incompatible module %s%s "
1782 "uses future GPL-only symbol '%s'\n", m, e, s);
1783 break;
1784 case export_plain:
1785 case export_unused:
1786 case export_unknown:
1787 /* ignore */
1788 break;
1789 }
1790}
1791
1792static void check_for_unused(enum export exp, const char *m, const char *s)
1793{
1794 const char *e = is_vmlinux(m) ?"":".ko";
1795
1796 switch (exp) {
1797 case export_unused:
1798 case export_unused_gpl:
1799 warn("modpost: module %s%s "
1800 "uses symbol '%s' marked UNUSED\n", m, e, s);
1801 break;
1802 default:
1803 /* ignore */
1804 break;
1805 }
1806}
1807
1808static void check_exports(struct module *mod)
1809{
1810 struct symbol *s, *exp;
1811
1812 for (s = mod->unres; s; s = s->next) {
1813 const char *basename;
1814 exp = find_symbol(s->name);
1815 if (!exp || exp->module == mod)
1816 continue;
1817 basename = strrchr(mod->name, '/');
1818 if (basename)
1819 basename++;
1820 else
1821 basename = mod->name;
1822 if (!mod->gpl_compatible)
1823 check_for_gpl_usage(exp->export, basename, exp->name);
1824 check_for_unused(exp->export, basename, exp->name);
1825 }
1826}
1827
1828/**
1829 * Header for the generated file
1830 **/
1831static void add_header(struct buffer *b, struct module *mod)
1832{
1833 buf_printf(b, "#include <linux/module.h>\n");
1834 buf_printf(b, "#include <linux/vermagic.h>\n");
1835 buf_printf(b, "#include <linux/compiler.h>\n");
1836 buf_printf(b, "\n");
1837 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1838 buf_printf(b, "\n");
1839 buf_printf(b, "struct module __this_module\n");
1840 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
1841 buf_printf(b, " .name = KBUILD_MODNAME,\n");
1842 if (mod->has_init)
1843 buf_printf(b, " .init = init_module,\n");
1844 if (mod->has_cleanup)
1845 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
1846 " .exit = cleanup_module,\n"
1847 "#endif\n");
1848 buf_printf(b, " .arch = MODULE_ARCH_INIT,\n");
1849 buf_printf(b, "};\n");
1850}
1851
1852static void add_staging_flag(struct buffer *b, const char *name)
1853{
1854 static const char *staging_dir = "drivers/staging";
1855
1856 if (strncmp(staging_dir, name, strlen(staging_dir)) == 0)
1857 buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
1858}
1859
1860/**
1861 * Record CRCs for unresolved symbols
1862 **/
1863static int add_versions(struct buffer *b, struct module *mod)
1864{
1865 struct symbol *s, *exp;
1866 int err = 0;
1867
1868 for (s = mod->unres; s; s = s->next) {
1869 exp = find_symbol(s->name);
1870 if (!exp || exp->module == mod) {
1871 if (have_vmlinux && !s->weak) {
1872 if (warn_unresolved) {
1873 warn("\"%s\" [%s.ko] undefined!\n",
1874 s->name, mod->name);
1875 } else {
1876 merror("\"%s\" [%s.ko] undefined!\n",
1877 s->name, mod->name);
1878 err = 1;
1879 }
1880 }
1881 continue;
1882 }
1883 s->module = exp->module;
1884 s->crc_valid = exp->crc_valid;
1885 s->crc = exp->crc;
1886 }
1887
1888 if (!modversions)
1889 return err;
1890
1891 buf_printf(b, "\n");
1892 buf_printf(b, "static const struct modversion_info ____versions[]\n");
1893 buf_printf(b, "__used\n");
1894 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n");
1895
1896 for (s = mod->unres; s; s = s->next) {
1897 if (!s->module)
1898 continue;
1899 if (!s->crc_valid) {
1900 warn("\"%s\" [%s.ko] has no CRC!\n",
1901 s->name, mod->name);
1902 continue;
1903 }
1904 buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name);
1905 }
1906
1907 buf_printf(b, "};\n");
1908
1909 return err;
1910}
1911
1912static void add_depends(struct buffer *b, struct module *mod,
1913 struct module *modules)
1914{
1915 struct symbol *s;
1916 struct module *m;
1917 int first = 1;
1918
1919 for (m = modules; m; m = m->next)
1920 m->seen = is_vmlinux(m->name);
1921
1922 buf_printf(b, "\n");
1923 buf_printf(b, "static const char __module_depends[]\n");
1924 buf_printf(b, "__used\n");
1925 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n");
1926 buf_printf(b, "\"depends=");
1927 for (s = mod->unres; s; s = s->next) {
1928 const char *p;
1929 if (!s->module)
1930 continue;
1931
1932 if (s->module->seen)
1933 continue;
1934
1935 s->module->seen = 1;
1936 p = strrchr(s->module->name, '/');
1937 if (p)
1938 p++;
1939 else
1940 p = s->module->name;
1941 buf_printf(b, "%s%s", first ? "" : ",", p);
1942 first = 0;
1943 }
1944 buf_printf(b, "\";\n");
1945}
1946
1947static void add_srcversion(struct buffer *b, struct module *mod)
1948{
1949 if (mod->srcversion[0]) {
1950 buf_printf(b, "\n");
1951 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
1952 mod->srcversion);
1953 }
1954}
1955
1956static void write_if_changed(struct buffer *b, const char *fname)
1957{
1958 char *tmp;
1959 FILE *file;
1960 struct stat st;
1961
1962 file = fopen(fname, "r");
1963 if (!file)
1964 goto write;
1965
1966 if (fstat(fileno(file), &st) < 0)
1967 goto close_write;
1968
1969 if (st.st_size != b->pos)
1970 goto close_write;
1971
1972 tmp = NOFAIL(malloc(b->pos));
1973 if (fread(tmp, 1, b->pos, file) != b->pos)
1974 goto free_write;
1975
1976 if (memcmp(tmp, b->p, b->pos) != 0)
1977 goto free_write;
1978
1979 free(tmp);
1980 fclose(file);
1981 return;
1982
1983 free_write:
1984 free(tmp);
1985 close_write:
1986 fclose(file);
1987 write:
1988 file = fopen(fname, "w");
1989 if (!file) {
1990 perror(fname);
1991 exit(1);
1992 }
1993 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
1994 perror(fname);
1995 exit(1);
1996 }
1997 fclose(file);
1998}
1999
2000/* parse Module.symvers file. line format:
2001 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
2002 **/
2003static void read_dump(const char *fname, unsigned int kernel)
2004{
2005 unsigned long size, pos = 0;
2006 void *file = grab_file(fname, &size);
2007 char *line;
2008
2009 if (!file)
2010 /* No symbol versions, silently ignore */
2011 return;
2012
2013 while ((line = get_next_line(&pos, file, size))) {
2014 char *symname, *modname, *d, *export, *end;
2015 unsigned int crc;
2016 struct module *mod;
2017 struct symbol *s;
2018
2019 if (!(symname = strchr(line, '\t')))
2020 goto fail;
2021 *symname++ = '\0';
2022 if (!(modname = strchr(symname, '\t')))
2023 goto fail;
2024 *modname++ = '\0';
2025 if ((export = strchr(modname, '\t')) != NULL)
2026 *export++ = '\0';
2027 if (export && ((end = strchr(export, '\t')) != NULL))
2028 *end = '\0';
2029 crc = strtoul(line, &d, 16);
2030 if (*symname == '\0' || *modname == '\0' || *d != '\0')
2031 goto fail;
2032 mod = find_module(modname);
2033 if (!mod) {
2034 if (is_vmlinux(modname))
2035 have_vmlinux = 1;
2036 mod = new_module(modname);
2037 mod->skip = 1;
2038 }
2039 s = sym_add_exported(symname, mod, export_no(export));
2040 s->kernel = kernel;
2041 s->preloaded = 1;
2042 sym_update_crc(symname, mod, crc, export_no(export));
2043 }
2044 return;
2045fail:
2046 fatal("parse error in symbol dump file\n");
2047}
2048
2049/* For normal builds always dump all symbols.
2050 * For external modules only dump symbols
2051 * that are not read from kernel Module.symvers.
2052 **/
2053static int dump_sym(struct symbol *sym)
2054{
2055 if (!external_module)
2056 return 1;
2057 if (sym->vmlinux || sym->kernel)
2058 return 0;
2059 return 1;
2060}
2061
2062static void write_dump(const char *fname)
2063{
2064 struct buffer buf = { };
2065 struct symbol *symbol;
2066 int n;
2067
2068 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
2069 symbol = symbolhash[n];
2070 while (symbol) {
2071 if (dump_sym(symbol))
2072 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
2073 symbol->crc, symbol->name,
2074 symbol->module->name,
2075 export_str(symbol->export));
2076 symbol = symbol->next;
2077 }
2078 }
2079 write_if_changed(&buf, fname);
2080}
2081
2082struct ext_sym_list {
2083 struct ext_sym_list *next;
2084 const char *file;
2085};
2086
2087int main(int argc, char **argv)
2088{
2089 struct module *mod;
2090 struct buffer buf = { };
2091 char *kernel_read = NULL, *module_read = NULL;
2092 char *dump_write = NULL;
2093 int opt;
2094 int err;
2095 struct ext_sym_list *extsym_iter;
2096 struct ext_sym_list *extsym_start = NULL;
2097
2098 while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) {
2099 switch (opt) {
2100 case 'i':
2101 kernel_read = optarg;
2102 break;
2103 case 'I':
2104 module_read = optarg;
2105 external_module = 1;
2106 break;
2107 case 'c':
2108 cross_build = 1;
2109 break;
2110 case 'e':
2111 external_module = 1;
2112 extsym_iter =
2113 NOFAIL(malloc(sizeof(*extsym_iter)));
2114 extsym_iter->next = extsym_start;
2115 extsym_iter->file = optarg;
2116 extsym_start = extsym_iter;
2117 break;
2118 case 'm':
2119 modversions = 1;
2120 break;
2121 case 'o':
2122 dump_write = optarg;
2123 break;
2124 case 'a':
2125 all_versions = 1;
2126 break;
2127 case 's':
2128 vmlinux_section_warnings = 0;
2129 break;
2130 case 'S':
2131 sec_mismatch_verbose = 0;
2132 break;
2133 case 'w':
2134 warn_unresolved = 1;
2135 break;
2136 default:
2137 exit(1);
2138 }
2139 }
2140
2141 if (kernel_read)
2142 read_dump(kernel_read, 1);
2143 if (module_read)
2144 read_dump(module_read, 0);
2145 while (extsym_start) {
2146 read_dump(extsym_start->file, 0);
2147 extsym_iter = extsym_start->next;
2148 free(extsym_start);
2149 extsym_start = extsym_iter;
2150 }
2151
2152 while (optind < argc)
2153 read_symbols(argv[optind++]);
2154
2155 for (mod = modules; mod; mod = mod->next) {
2156 if (mod->skip)
2157 continue;
2158 check_exports(mod);
2159 }
2160
2161 err = 0;
2162
2163 for (mod = modules; mod; mod = mod->next) {
2164 char fname[strlen(mod->name) + 10];
2165
2166 if (mod->skip)
2167 continue;
2168
2169 buf.pos = 0;
2170
2171 add_header(&buf, mod);
2172 add_staging_flag(&buf, mod->name);
2173 err |= add_versions(&buf, mod);
2174 add_depends(&buf, mod, modules);
2175 add_moddevtable(&buf, mod);
2176 add_srcversion(&buf, mod);
2177
2178 sprintf(fname, "%s.mod.c", mod->name);
2179 write_if_changed(&buf, fname);
2180 }
2181
2182 if (dump_write)
2183 write_dump(dump_write);
2184 if (sec_mismatch_count && !sec_mismatch_verbose)
2185 warn("modpost: Found %d section mismatch(es).\n"
2186 "To see full details build your kernel with:\n"
2187 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
2188 sec_mismatch_count);
2189
2190 return err;
2191}