?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
kbuild: make modpost section warnings clearer
[linux-2.6/sactl.git] / scripts / mod / modpost.c
blob2fcdbc7a1ee5325a6e24fc48db0c23e90dd6859a
1 /* Postprocess module symbol versions
2 *
3 * Copyright 2003 Kai Germaschewski
4 * Copyright 2002-2004 Rusty Russell, IBM Corporation
5 * Copyright 2006 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 #include <ctype.h>
15 #include "modpost.h"
16 #include "../../include/linux/license.h"
17
18 /* Are we using CONFIG_MODVERSIONS? */
19 int modversions = 0;
20 /* Warn about undefined symbols? (do so if we have vmlinux) */
21 int have_vmlinux = 0;
22 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */
23 static int all_versions = 0;
24 /* If we are modposting external module set to 1 */
25 static int external_module = 0;
26 /* Only warn about unresolved symbols */
27 static int warn_unresolved = 0;
28 /* How a symbol is exported */
29 enum export {
30 export_plain, export_unused, export_gpl,
31 export_unused_gpl, export_gpl_future, export_unknown
32 };
33
34 void fatal(const char *fmt, ...)
35 {
36 va_list arglist;
37
38 fprintf(stderr, "FATAL: ");
39
40 va_start(arglist, fmt);
41 vfprintf(stderr, fmt, arglist);
42 va_end(arglist);
43
44 exit(1);
45 }
46
47 void warn(const char *fmt, ...)
48 {
49 va_list arglist;
50
51 fprintf(stderr, "WARNING: ");
52
53 va_start(arglist, fmt);
54 vfprintf(stderr, fmt, arglist);
55 va_end(arglist);
56 }
57
58 void merror(const char *fmt, ...)
59 {
60 va_list arglist;
61
62 fprintf(stderr, "ERROR: ");
63
64 va_start(arglist, fmt);
65 vfprintf(stderr, fmt, arglist);
66 va_end(arglist);
67 }
68
69 static int is_vmlinux(const char *modname)
70 {
71 const char *myname;
72
73 if ((myname = strrchr(modname, '/')))
74 myname++;
75 else
76 myname = modname;
77
78 return strcmp(myname, "vmlinux") == 0;
79 }
80
81 void *do_nofail(void *ptr, const char *expr)
82 {
83 if (!ptr) {
84 fatal("modpost: Memory allocation failure: %s.\n", expr);
85 }
86 return ptr;
87 }
88
89 /* A list of all modules we processed */
90
91 static struct module *modules;
92
93 static struct module *find_module(char *modname)
94 {
95 struct module *mod;
96
97 for (mod = modules; mod; mod = mod->next)
98 if (strcmp(mod->name, modname) == 0)
99 break;
100 return mod;
101 }
102
103 static struct module *new_module(char *modname)
104 {
105 struct module *mod;
106 char *p, *s;
107
108 mod = NOFAIL(malloc(sizeof(*mod)));
109 memset(mod, 0, sizeof(*mod));
110 p = NOFAIL(strdup(modname));
111
112 /* strip trailing .o */
113 if ((s = strrchr(p, '.')) != NULL)
114 if (strcmp(s, ".o") == 0)
115 *s = '\0';
116
117 /* add to list */
118 mod->name = p;
119 mod->gpl_compatible = -1;
120 mod->next = modules;
121 modules = mod;
122
123 return mod;
124 }
125
126 /* A hash of all exported symbols,
127 * struct symbol is also used for lists of unresolved symbols */
128
129 #define SYMBOL_HASH_SIZE 1024
130
131 struct symbol {
132 struct symbol *next;
133 struct module *module;
134 unsigned int crc;
135 int crc_valid;
136 unsigned int weak:1;
137 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */
138 unsigned int kernel:1; /* 1 if symbol is from kernel
139 * (only for external modules) **/
140 unsigned int preloaded:1; /* 1 if symbol from Module.symvers */
141 enum export export; /* Type of export */
142 char name[0];
143 };
144
145 static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
146
147 /* This is based on the hash agorithm from gdbm, via tdb */
148 static inline unsigned int tdb_hash(const char *name)
149 {
150 unsigned value; /* Used to compute the hash value. */
151 unsigned i; /* Used to cycle through random values. */
152
153 /* Set the initial value from the key size. */
154 for (value = 0x238F13AF * strlen(name), i=0; name[i]; i++)
155 value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
156
157 return (1103515243 * value + 12345);
158 }
159
160 /**
161 * Allocate a new symbols for use in the hash of exported symbols or
162 * the list of unresolved symbols per module
163 **/
164 static struct symbol *alloc_symbol(const char *name, unsigned int weak,
165 struct symbol *next)
166 {
167 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
168
169 memset(s, 0, sizeof(*s));
170 strcpy(s->name, name);
171 s->weak = weak;
172 s->next = next;
173 return s;
174 }
175
176 /* For the hash of exported symbols */
177 static struct symbol *new_symbol(const char *name, struct module *module,
178 enum export export)
179 {
180 unsigned int hash;
181 struct symbol *new;
182
183 hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
184 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
185 new->module = module;
186 new->export = export;
187 return new;
188 }
189
190 static struct symbol *find_symbol(const char *name)
191 {
192 struct symbol *s;
193
194 /* For our purposes, .foo matches foo. PPC64 needs this. */
195 if (name[0] == '.')
196 name++;
197
198 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s=s->next) {
199 if (strcmp(s->name, name) == 0)
200 return s;
201 }
202 return NULL;
203 }
204
205 static struct {
206 const char *str;
207 enum export export;
208 } export_list[] = {
209 { .str = "EXPORT_SYMBOL", .export = export_plain },
210 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
211 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
212 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
213 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
214 { .str = "(unknown)", .export = export_unknown },
215 };
216
217
218 static const char *export_str(enum export ex)
219 {
220 return export_list[ex].str;
221 }
222
223 static enum export export_no(const char * s)
224 {
225 int i;
226 if (!s)
227 return export_unknown;
228 for (i = 0; export_list[i].export != export_unknown; i++) {
229 if (strcmp(export_list[i].str, s) == 0)
230 return export_list[i].export;
231 }
232 return export_unknown;
233 }
234
235 static enum export export_from_sec(struct elf_info *elf, Elf_Section sec)
236 {
237 if (sec == elf->export_sec)
238 return export_plain;
239 else if (sec == elf->export_unused_sec)
240 return export_unused;
241 else if (sec == elf->export_gpl_sec)
242 return export_gpl;
243 else if (sec == elf->export_unused_gpl_sec)
244 return export_unused_gpl;
245 else if (sec == elf->export_gpl_future_sec)
246 return export_gpl_future;
247 else
248 return export_unknown;
249 }
250
251 /**
252 * Add an exported symbol - it may have already been added without a
253 * CRC, in this case just update the CRC
254 **/
255 static struct symbol *sym_add_exported(const char *name, struct module *mod,
256 enum export export)
257 {
258 struct symbol *s = find_symbol(name);
259
260 if (!s) {
261 s = new_symbol(name, mod, export);
262 } else {
263 if (!s->preloaded) {
264 warn("%s: '%s' exported twice. Previous export "
265 "was in %s%s\n", mod->name, name,
266 s->module->name,
267 is_vmlinux(s->module->name) ?"":".ko");
268 }
269 }
270 s->preloaded = 0;
271 s->vmlinux = is_vmlinux(mod->name);
272 s->kernel = 0;
273 s->export = export;
274 return s;
275 }
276
277 static void sym_update_crc(const char *name, struct module *mod,
278 unsigned int crc, enum export export)
279 {
280 struct symbol *s = find_symbol(name);
281
282 if (!s)
283 s = new_symbol(name, mod, export);
284 s->crc = crc;
285 s->crc_valid = 1;
286 }
287
288 void *grab_file(const char *filename, unsigned long *size)
289 {
290 struct stat st;
291 void *map;
292 int fd;
293
294 fd = open(filename, O_RDONLY);
295 if (fd < 0 || fstat(fd, &st) != 0)
296 return NULL;
297
298 *size = st.st_size;
299 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
300 close(fd);
301
302 if (map == MAP_FAILED)
303 return NULL;
304 return map;
305 }
306
307 /**
308 * Return a copy of the next line in a mmap'ed file.
309 * spaces in the beginning of the line is trimmed away.
310 * Return a pointer to a static buffer.
311 **/
312 char* get_next_line(unsigned long *pos, void *file, unsigned long size)
313 {
314 static char line[4096];
315 int skip = 1;
316 size_t len = 0;
317 signed char *p = (signed char *)file + *pos;
318 char *s = line;
319
320 for (; *pos < size ; (*pos)++)
321 {
322 if (skip && isspace(*p)) {
323 p++;
324 continue;
325 }
326 skip = 0;
327 if (*p != '\n' && (*pos < size)) {
328 len++;
329 *s++ = *p++;
330 if (len > 4095)
331 break; /* Too long, stop */
332 } else {
333 /* End of string */
334 *s = '\0';
335 return line;
336 }
337 }
338 /* End of buffer */
339 return NULL;
340 }
341
342 void release_file(void *file, unsigned long size)
343 {
344 munmap(file, size);
345 }
346
347 static int parse_elf(struct elf_info *info, const char *filename)
348 {
349 unsigned int i;
350 Elf_Ehdr *hdr;
351 Elf_Shdr *sechdrs;
352 Elf_Sym *sym;
353
354 hdr = grab_file(filename, &info->size);
355 if (!hdr) {
356 perror(filename);
357 exit(1);
358 }
359 info->hdr = hdr;
360 if (info->size < sizeof(*hdr)) {
361 /* file too small, assume this is an empty .o file */
362 return 0;
363 }
364 /* Is this a valid ELF file? */
365 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
366 (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
367 (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
368 (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
369 /* Not an ELF file - silently ignore it */
370 return 0;
371 }
372 /* Fix endianness in ELF header */
373 hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
374 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
375 hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
376 hdr->e_machine = TO_NATIVE(hdr->e_machine);
377 sechdrs = (void *)hdr + hdr->e_shoff;
378 info->sechdrs = sechdrs;
379
380 /* Fix endianness in section headers */
381 for (i = 0; i < hdr->e_shnum; i++) {
382 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
383 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
384 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
385 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
386 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
387 }
388 /* Find symbol table. */
389 for (i = 1; i < hdr->e_shnum; i++) {
390 const char *secstrings
391 = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
392 const char *secname;
393
394 if (sechdrs[i].sh_offset > info->size) {
395 fatal("%s is truncated. sechdrs[i].sh_offset=%u > sizeof(*hrd)=%ul\n", filename, (unsigned int)sechdrs[i].sh_offset, sizeof(*hdr));
396 return 0;
397 }
398 secname = secstrings + sechdrs[i].sh_name;
399 if (strcmp(secname, ".modinfo") == 0) {
400 info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
401 info->modinfo_len = sechdrs[i].sh_size;
402 } else if (strcmp(secname, "__ksymtab") == 0)
403 info->export_sec = i;
404 else if (strcmp(secname, "__ksymtab_unused") == 0)
405 info->export_unused_sec = i;
406 else if (strcmp(secname, "__ksymtab_gpl") == 0)
407 info->export_gpl_sec = i;
408 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
409 info->export_unused_gpl_sec = i;
410 else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
411 info->export_gpl_future_sec = i;
412
413 if (sechdrs[i].sh_type != SHT_SYMTAB)
414 continue;
415
416 info->symtab_start = (void *)hdr + sechdrs[i].sh_offset;
417 info->symtab_stop = (void *)hdr + sechdrs[i].sh_offset
418 + sechdrs[i].sh_size;
419 info->strtab = (void *)hdr +
420 sechdrs[sechdrs[i].sh_link].sh_offset;
421 }
422 if (!info->symtab_start) {
423 fatal("%s has no symtab?\n", filename);
424 }
425 /* Fix endianness in symbols */
426 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
427 sym->st_shndx = TO_NATIVE(sym->st_shndx);
428 sym->st_name = TO_NATIVE(sym->st_name);
429 sym->st_value = TO_NATIVE(sym->st_value);
430 sym->st_size = TO_NATIVE(sym->st_size);
431 }
432 return 1;
433 }
434
435 static void parse_elf_finish(struct elf_info *info)
436 {
437 release_file(info->hdr, info->size);
438 }
439
440 #define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_"
441 #define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
442
443 static void handle_modversions(struct module *mod, struct elf_info *info,
444 Elf_Sym *sym, const char *symname)
445 {
446 unsigned int crc;
447 enum export export = export_from_sec(info, sym->st_shndx);
448
449 switch (sym->st_shndx) {
450 case SHN_COMMON:
451 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
452 break;
453 case SHN_ABS:
454 /* CRC'd symbol */
455 if (memcmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
456 crc = (unsigned int) sym->st_value;
457 sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
458 export);
459 }
460 break;
461 case SHN_UNDEF:
462 /* undefined symbol */
463 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
464 ELF_ST_BIND(sym->st_info) != STB_WEAK)
465 break;
466 /* ignore global offset table */
467 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
468 break;
469 /* ignore __this_module, it will be resolved shortly */
470 if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0)
471 break;
472 /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
473 #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
474 /* add compatibility with older glibc */
475 #ifndef STT_SPARC_REGISTER
476 #define STT_SPARC_REGISTER STT_REGISTER
477 #endif
478 if (info->hdr->e_machine == EM_SPARC ||
479 info->hdr->e_machine == EM_SPARCV9) {
480 /* Ignore register directives. */
481 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
482 break;
483 if (symname[0] == '.') {
484 char *munged = strdup(symname);
485 munged[0] = '_';
486 munged[1] = toupper(munged[1]);
487 symname = munged;
488 }
489 }
490 #endif
491
492 if (memcmp(symname, MODULE_SYMBOL_PREFIX,
493 strlen(MODULE_SYMBOL_PREFIX)) == 0)
494 mod->unres = alloc_symbol(symname +
495 strlen(MODULE_SYMBOL_PREFIX),
496 ELF_ST_BIND(sym->st_info) == STB_WEAK,
497 mod->unres);
498 break;
499 default:
500 /* All exported symbols */
501 if (memcmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
502 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
503 export);
504 }
505 if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
506 mod->has_init = 1;
507 if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0)
508 mod->has_cleanup = 1;
509 break;
510 }
511 }
512
513 /**
514 * Parse tag=value strings from .modinfo section
515 **/
516 static char *next_string(char *string, unsigned long *secsize)
517 {
518 /* Skip non-zero chars */
519 while (string[0]) {
520 string++;
521 if ((*secsize)-- <= 1)
522 return NULL;
523 }
524
525 /* Skip any zero padding. */
526 while (!string[0]) {
527 string++;
528 if ((*secsize)-- <= 1)
529 return NULL;
530 }
531 return string;
532 }
533
534 static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
535 const char *tag, char *info)
536 {
537 char *p;
538 unsigned int taglen = strlen(tag);
539 unsigned long size = modinfo_len;
540
541 if (info) {
542 size -= info - (char *)modinfo;
543 modinfo = next_string(info, &size);
544 }
545
546 for (p = modinfo; p; p = next_string(p, &size)) {
547 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
548 return p + taglen + 1;
549 }
550 return NULL;
551 }
552
553 static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
554 const char *tag)
555
556 {
557 return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
558 }
559
560 /**
561 * Test if string s ends in string sub
562 * return 0 if match
563 **/
564 static int strrcmp(const char *s, const char *sub)
565 {
566 int slen, sublen;
567
568 if (!s || !sub)
569 return 1;
570
571 slen = strlen(s);
572 sublen = strlen(sub);
573
574 if ((slen == 0) || (sublen == 0))
575 return 1;
576
577 if (sublen > slen)
578 return 1;
579
580 return memcmp(s + slen - sublen, sub, sublen);
581 }
582
583 /**
584 * Whitelist to allow certain references to pass with no warning.
585 * Pattern 1:
586 * If a module parameter is declared __initdata and permissions=0
587 * then this is legal despite the warning generated.
588 * We cannot see value of permissions here, so just ignore
589 * this pattern.
590 * The pattern is identified by:
591 * tosec = .init.data
592 * fromsec = .data*
593 * atsym =__param*
594 *
595 * Pattern 2:
596 * Many drivers utilise a *driver container with references to
597 * add, remove, probe functions etc.
598 * These functions may often be marked __init and we do not want to
599 * warn here.
600 * the pattern is identified by:
601 * tosec = .init.text | .exit.text | .init.data
602 * fromsec = .data
603 * atsym = *driver, *_template, *_sht, *_ops, *_probe, *probe_one, *_console
604 *
605 * Pattern 3:
606 * Whitelist all references from .pci_fixup* section to .init.text
607 * This is part of the PCI init when built-in
608 *
609 * Pattern 4:
610 * Whitelist all refereces from .text.head to .init.data
611 * Whitelist all refereces from .text.head to .init.text
612 *
613 * Pattern 5:
614 * Some symbols belong to init section but still it is ok to reference
615 * these from non-init sections as these symbols don't have any memory
616 * allocated for them and symbol address and value are same. So even
617 * if init section is freed, its ok to reference those symbols.
618 * For ex. symbols marking the init section boundaries.
619 * This pattern is identified by
620 * refsymname = __init_begin, _sinittext, _einittext
621 *
622 * Pattern 6:
623 * During the early init phase we have references from .init.text to
624 * .text we have an intended section mismatch - do not warn about it.
625 * See kernel_init() in init/main.c
626 * tosec = .init.text
627 * fromsec = .text
628 * atsym = kernel_init
629 *
630 * Pattern 7:
631 * Logos used in drivers/video/logo reside in __initdata but the
632 * funtion that references them are EXPORT_SYMBOL() so cannot be
633 * marker __init. So we whitelist them here.
634 * The pattern is:
635 * tosec = .init.data
636 * fromsec = .text*
637 * refsymname = logo_
638 *
639 * Pattern 8:
640 * Symbols contained in .paravirtprobe may safely reference .init.text.
641 * The pattern is:
642 * tosec = .init.text
643 * fromsec = .paravirtprobe
644 *
645 * Pattern 9:
646 * Some of functions are common code between boot time and hotplug
647 * time. The bootmem allocater is called only boot time in its
648 * functions. So it's ok to reference.
649 * tosec = .init.text
650 *
651 * Pattern 10:
652 * ia64 has machvec table for each platform. It is mixture of function
653 * pointer of .init.text and .text.
654 * fromsec = .machvec
655 **/
656 static int secref_whitelist(const char *modname, const char *tosec,
657 const char *fromsec, const char *atsym,
658 const char *refsymname)
659 {
660 int f1 = 1, f2 = 1;
661 const char **s;
662 const char *pat2sym[] = {
663 "driver",
664 "_template", /* scsi uses *_template a lot */
665 "_sht", /* scsi also used *_sht to some extent */
666 "_ops",
667 "_probe",
668 "_probe_one",
669 "_console",
670 "apic_es7000",
671 NULL
672 };
673
674 const char *pat3refsym[] = {
675 "__init_begin",
676 "_sinittext",
677 "_einittext",
678 NULL
679 };
680
681 const char *pat4sym[] = {
682 "sparse_index_alloc",
683 "zone_wait_table_init",
684 NULL
685 };
686
687 /* Check for pattern 1 */
688 if (strcmp(tosec, ".init.data") != 0)
689 f1 = 0;
690 if (strncmp(fromsec, ".data", strlen(".data")) != 0)
691 f1 = 0;
692 if (strncmp(atsym, "__param", strlen("__param")) != 0)
693 f1 = 0;
694
695 if (f1)
696 return f1;
697
698 /* Check for pattern 2 */
699 if ((strcmp(tosec, ".init.text") != 0) &&
700 (strcmp(tosec, ".exit.text") != 0) &&
701 (strcmp(tosec, ".init.data") != 0))
702 f2 = 0;
703 if (strcmp(fromsec, ".data") != 0)
704 f2 = 0;
705
706 for (s = pat2sym; *s; s++)
707 if (strrcmp(atsym, *s) == 0)
708 f1 = 1;
709 if (f1 && f2)
710 return 1;
711
712 /* Check for pattern 3 */
713 if ((strncmp(fromsec, ".pci_fixup", strlen(".pci_fixup")) == 0) &&
714 (strcmp(tosec, ".init.text") == 0))
715 return 1;
716
717 /* Check for pattern 4 */
718 if ((strcmp(fromsec, ".text.head") == 0) &&
719 ((strcmp(tosec, ".init.data") == 0) ||
720 (strcmp(tosec, ".init.text") == 0)))
721 return 1;
722
723 /* Check for pattern 5 */
724 for (s = pat3refsym; *s; s++)
725 if (strcmp(refsymname, *s) == 0)
726 return 1;
727
728 /* Check for pattern 6 */
729 if ((strcmp(tosec, ".init.text") == 0) &&
730 (strcmp(fromsec, ".text") == 0) &&
731 (strcmp(refsymname, "kernel_init") == 0))
732 return 1;
733
734 /* Check for pattern 7 */
735 if ((strcmp(tosec, ".init.data") == 0) &&
736 (strncmp(fromsec, ".text", strlen(".text")) == 0) &&
737 (strncmp(refsymname, "logo_", strlen("logo_")) == 0))
738 return 1;
739
740 /* Check for pattern 8 */
741 if ((strcmp(tosec, ".init.text") == 0) &&
742 (strcmp(fromsec, ".paravirtprobe") == 0))
743 return 1;
744
745 /* Check for pattern 9 */
746 if ((strcmp(tosec, ".init.text") == 0) &&
747 (strcmp(fromsec, ".text") == 0))
748 for (s = pat4sym; *s; s++)
749 if (strcmp(atsym, *s) == 0)
750 return 1;
751
752 /* Check for pattern 10 */
753 if (strcmp(fromsec, ".machvec") == 0)
754 return 1;
755
756 return 0;
757 }
758
759 /**
760 * Find symbol based on relocation record info.
761 * In some cases the symbol supplied is a valid symbol so
762 * return refsym. If st_name != 0 we assume this is a valid symbol.
763 * In other cases the symbol needs to be looked up in the symbol table
764 * based on section and address.
765 * **/
766 static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf_Addr addr,
767 Elf_Sym *relsym)
768 {
769 Elf_Sym *sym;
770
771 if (relsym->st_name != 0)
772 return relsym;
773 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
774 if (sym->st_shndx != relsym->st_shndx)
775 continue;
776 if (sym->st_value == addr)
777 return sym;
778 }
779 return NULL;
780 }
781
782 static inline int is_arm_mapping_symbol(const char *str)
783 {
784 return str[0] == '$' && strchr("atd", str[1])
785 && (str[2] == '\0' || str[2] == '.');
786 }
787
788 /*
789 * If there's no name there, ignore it; likewise, ignore it if it's
790 * one of the magic symbols emitted used by current ARM tools.
791 *
792 * Otherwise if find_symbols_between() returns those symbols, they'll
793 * fail the whitelist tests and cause lots of false alarms ... fixable
794 * only by merging __exit and __init sections into __text, bloating
795 * the kernel (which is especially evil on embedded platforms).
796 */
797 static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
798 {
799 const char *name = elf->strtab + sym->st_name;
800
801 if (!name || !strlen(name))
802 return 0;
803 return !is_arm_mapping_symbol(name);
804 }
805
806 /*
807 * Find symbols before or equal addr and after addr - in the section sec.
808 * If we find two symbols with equal offset prefer one with a valid name.
809 * The ELF format may have a better way to detect what type of symbol
810 * it is, but this works for now.
811 **/
812 static void find_symbols_between(struct elf_info *elf, Elf_Addr addr,
813 const char *sec,
814 Elf_Sym **before, Elf_Sym **after)
815 {
816 Elf_Sym *sym;
817 Elf_Ehdr *hdr = elf->hdr;
818 Elf_Addr beforediff = ~0;
819 Elf_Addr afterdiff = ~0;
820 const char *secstrings = (void *)hdr +
821 elf->sechdrs[hdr->e_shstrndx].sh_offset;
822
823 *before = NULL;
824 *after = NULL;
825
826 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
827 const char *symsec;
828
829 if (sym->st_shndx >= SHN_LORESERVE)
830 continue;
831 symsec = secstrings + elf->sechdrs[sym->st_shndx].sh_name;
832 if (strcmp(symsec, sec) != 0)
833 continue;
834 if (!is_valid_name(elf, sym))
835 continue;
836 if (sym->st_value <= addr) {
837 if ((addr - sym->st_value) < beforediff) {
838 beforediff = addr - sym->st_value;
839 *before = sym;
840 }
841 else if ((addr - sym->st_value) == beforediff) {
842 *before = sym;
843 }
844 }
845 else
846 {
847 if ((sym->st_value - addr) < afterdiff) {
848 afterdiff = sym->st_value - addr;
849 *after = sym;
850 }
851 else if ((sym->st_value - addr) == afterdiff) {
852 *after = sym;
853 }
854 }
855 }
856 }
857
858 /**
859 * Print a warning about a section mismatch.
860 * Try to find symbols near it so user can find it.
861 * Check whitelist before warning - it may be a false positive.
862 **/
863 static void warn_sec_mismatch(const char *modname, const char *fromsec,
864 struct elf_info *elf, Elf_Sym *sym, Elf_Rela r)
865 {
866 const char *refsymname = "";
867 Elf_Sym *before, *after;
868 Elf_Sym *refsym;
869 Elf_Ehdr *hdr = elf->hdr;
870 Elf_Shdr *sechdrs = elf->sechdrs;
871 const char *secstrings = (void *)hdr +
872 sechdrs[hdr->e_shstrndx].sh_offset;
873 const char *secname = secstrings + sechdrs[sym->st_shndx].sh_name;
874
875 find_symbols_between(elf, r.r_offset, fromsec, &before, &after);
876
877 refsym = find_elf_symbol(elf, r.r_addend, sym);
878 if (refsym && strlen(elf->strtab + refsym->st_name))
879 refsymname = elf->strtab + refsym->st_name;
880
881 /* check whitelist - we may ignore it */
882 if (before &&
883 secref_whitelist(modname, secname, fromsec,
884 elf->strtab + before->st_name, refsymname))
885 return;
886
887 if (before && after) {
888 warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
889 "(between '%s' and '%s')\n",
890 modname, fromsec, (unsigned long long)r.r_offset,
891 secname, refsymname,
892 elf->strtab + before->st_name,
893 elf->strtab + after->st_name);
894 } else if (before) {
895 warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
896 "(after '%s')\n",
897 modname, fromsec, (unsigned long long)r.r_offset,
898 secname, refsymname,
899 elf->strtab + before->st_name);
900 } else if (after) {
901 warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
902 "before '%s' (at offset -0x%llx)\n",
903 modname, fromsec, (unsigned long long)r.r_offset,
904 secname, refsymname,
905 elf->strtab + after->st_name);
906 } else {
907 warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s\n",
908 modname, fromsec, (unsigned long long)r.r_offset,
909 secname, refsymname);
910 }
911 }
912
913 /**
914 * A module includes a number of sections that are discarded
915 * either when loaded or when used as built-in.
916 * For loaded modules all functions marked __init and all data
917 * marked __initdata will be discarded when the module has been intialized.
918 * Likewise for modules used built-in the sections marked __exit
919 * are discarded because __exit marked function are supposed to be called
920 * only when a moduel is unloaded which never happes for built-in modules.
921 * The check_sec_ref() function traverses all relocation records
922 * to find all references to a section that reference a section that will
923 * be discarded and warns about it.
924 **/
925 static void check_sec_ref(struct module *mod, const char *modname,
926 struct elf_info *elf,
927 int section(const char*),
928 int section_ref_ok(const char *))
929 {
930 int i;
931 Elf_Sym *sym;
932 Elf_Ehdr *hdr = elf->hdr;
933 Elf_Shdr *sechdrs = elf->sechdrs;
934 const char *secstrings = (void *)hdr +
935 sechdrs[hdr->e_shstrndx].sh_offset;
936
937 /* Walk through all sections */
938 for (i = 0; i < hdr->e_shnum; i++) {
939 const char *name = secstrings + sechdrs[i].sh_name;
940 const char *secname;
941 Elf_Rela r;
942 unsigned int r_sym;
943 /* We want to process only relocation sections and not .init */
944 if (sechdrs[i].sh_type == SHT_RELA) {
945 Elf_Rela *rela;
946 Elf_Rela *start = (void *)hdr + sechdrs[i].sh_offset;
947 Elf_Rela *stop = (void*)start + sechdrs[i].sh_size;
948 name += strlen(".rela");
949 if (section_ref_ok(name))
950 continue;
951
952 for (rela = start; rela < stop; rela++) {
953 r.r_offset = TO_NATIVE(rela->r_offset);
954 #if KERNEL_ELFCLASS == ELFCLASS64
955 if (hdr->e_machine == EM_MIPS) {
956 r_sym = ELF64_MIPS_R_SYM(rela->r_info);
957 r_sym = TO_NATIVE(r_sym);
958 } else {
959 r.r_info = TO_NATIVE(rela->r_info);
960 r_sym = ELF_R_SYM(r.r_info);
961 }
962 #else
963 r.r_info = TO_NATIVE(rela->r_info);
964 r_sym = ELF_R_SYM(r.r_info);
965 #endif
966 r.r_addend = TO_NATIVE(rela->r_addend);
967 sym = elf->symtab_start + r_sym;
968 /* Skip special sections */
969 if (sym->st_shndx >= SHN_LORESERVE)
970 continue;
971
972 secname = secstrings +
973 sechdrs[sym->st_shndx].sh_name;
974 if (section(secname))
975 warn_sec_mismatch(modname, name,
976 elf, sym, r);
977 }
978 } else if (sechdrs[i].sh_type == SHT_REL) {
979 Elf_Rel *rel;
980 Elf_Rel *start = (void *)hdr + sechdrs[i].sh_offset;
981 Elf_Rel *stop = (void*)start + sechdrs[i].sh_size;
982 name += strlen(".rel");
983 if (section_ref_ok(name))
984 continue;
985
986 for (rel = start; rel < stop; rel++) {
987 r.r_offset = TO_NATIVE(rel->r_offset);
988 #if KERNEL_ELFCLASS == ELFCLASS64
989 if (hdr->e_machine == EM_MIPS) {
990 r_sym = ELF64_MIPS_R_SYM(rel->r_info);
991 r_sym = TO_NATIVE(r_sym);
992 } else {
993 r.r_info = TO_NATIVE(rel->r_info);
994 r_sym = ELF_R_SYM(r.r_info);
995 }
996 #else
997 r.r_info = TO_NATIVE(rel->r_info);
998 r_sym = ELF_R_SYM(r.r_info);
999 #endif
1000 r.r_addend = 0;
1001 sym = elf->symtab_start + r_sym;
1002 /* Skip special sections */
1003 if (sym->st_shndx >= SHN_LORESERVE)
1004 continue;
1005
1006 secname = secstrings +
1007 sechdrs[sym->st_shndx].sh_name;
1008 if (section(secname))
1009 warn_sec_mismatch(modname, name,
1010 elf, sym, r);
1011 }
1012 }
1013 }
1014 }
1015
1016 /**
1017 * Functions used only during module init is marked __init and is stored in
1018 * a .init.text section. Likewise data is marked __initdata and stored in
1019 * a .init.data section.
1020 * If this section is one of these sections return 1
1021 * See include/linux/init.h for the details
1022 **/
1023 static int init_section(const char *name)
1024 {
1025 if (strcmp(name, ".init") == 0)
1026 return 1;
1027 if (strncmp(name, ".init.", strlen(".init.")) == 0)
1028 return 1;
1029 return 0;
1030 }
1031
1032 /**
1033 * Identify sections from which references to a .init section is OK.
1034 *
1035 * Unfortunately references to read only data that referenced .init
1036 * sections had to be excluded. Almost all of these are false
1037 * positives, they are created by gcc. The downside of excluding rodata
1038 * is that there really are some user references from rodata to
1039 * init code, e.g. drivers/video/vgacon.c:
1040 *
1041 * const struct consw vga_con = {
1042 * con_startup: vgacon_startup,
1043 *
1044 * where vgacon_startup is __init. If you want to wade through the false
1045 * positives, take out the check for rodata.
1046 **/
1047 static int init_section_ref_ok(const char *name)
1048 {
1049 const char **s;
1050 /* Absolute section names */
1051 const char *namelist1[] = {
1052 ".init",
1053 ".opd", /* see comment [OPD] at exit_section_ref_ok() */
1054 ".toc1", /* used by ppc64 */
1055 ".stab",
1056 ".data.rel.ro", /* used by parisc64 */
1057 ".parainstructions",
1058 ".text.lock",
1059 "__bug_table", /* used by powerpc for BUG() */
1060 ".pci_fixup_header",
1061 ".pci_fixup_final",
1062 ".pdr",
1063 "__param",
1064 "__ex_table",
1065 ".fixup",
1066 ".smp_locks",
1067 ".plt", /* seen on ARCH=um build on x86_64. Harmless */
1068 "__ftr_fixup", /* powerpc cpu feature fixup */
1069 "__fw_ftr_fixup", /* powerpc firmware feature fixup */
1070 NULL
1071 };
1072 /* Start of section names */
1073 const char *namelist2[] = {
1074 ".init.",
1075 ".altinstructions",
1076 ".eh_frame",
1077 ".debug",
1078 ".parainstructions",
1079 ".rodata",
1080 NULL
1081 };
1082 /* part of section name */
1083 const char *namelist3 [] = {
1084 ".unwind", /* sample: IA_64.unwind.init.text */
1085 NULL
1086 };
1087
1088 for (s = namelist1; *s; s++)
1089 if (strcmp(*s, name) == 0)
1090 return 1;
1091 for (s = namelist2; *s; s++)
1092 if (strncmp(*s, name, strlen(*s)) == 0)
1093 return 1;
1094 for (s = namelist3; *s; s++)
1095 if (strstr(name, *s) != NULL)
1096 return 1;
1097 if (strrcmp(name, ".init") == 0)
1098 return 1;
1099 return 0;
1100 }
1101
1102 /*
1103 * Functions used only during module exit is marked __exit and is stored in
1104 * a .exit.text section. Likewise data is marked __exitdata and stored in
1105 * a .exit.data section.
1106 * If this section is one of these sections return 1
1107 * See include/linux/init.h for the details
1108 **/
1109 static int exit_section(const char *name)
1110 {
1111 if (strcmp(name, ".exit.text") == 0)
1112 return 1;
1113 if (strcmp(name, ".exit.data") == 0)
1114 return 1;
1115 return 0;
1116
1117 }
1118
1119 /*
1120 * Identify sections from which references to a .exit section is OK.
1121 *
1122 * [OPD] Keith Ownes <kaos@sgi.com> commented:
1123 * For our future {in}sanity, add a comment that this is the ppc .opd
1124 * section, not the ia64 .opd section.
1125 * ia64 .opd should not point to discarded sections.
1126 * [.rodata] like for .init.text we ignore .rodata references -same reason
1127 **/
1128 static int exit_section_ref_ok(const char *name)
1129 {
1130 const char **s;
1131 /* Absolute section names */
1132 const char *namelist1[] = {
1133 ".exit.text",
1134 ".exit.data",
1135 ".init.text",
1136 ".rodata",
1137 ".opd", /* See comment [OPD] */
1138 ".toc1", /* used by ppc64 */
1139 ".altinstructions",
1140 ".pdr",
1141 "__bug_table", /* used by powerpc for BUG() */
1142 ".exitcall.exit",
1143 ".eh_frame",
1144 ".parainstructions",
1145 ".stab",
1146 "__ex_table",
1147 ".fixup",
1148 ".smp_locks",
1149 ".plt", /* seen on ARCH=um build on x86_64. Harmless */
1150 NULL
1151 };
1152 /* Start of section names */
1153 const char *namelist2[] = {
1154 ".debug",
1155 NULL
1156 };
1157 /* part of section name */
1158 const char *namelist3 [] = {
1159 ".unwind", /* Sample: IA_64.unwind.exit.text */
1160 NULL
1161 };
1162
1163 for (s = namelist1; *s; s++)
1164 if (strcmp(*s, name) == 0)
1165 return 1;
1166 for (s = namelist2; *s; s++)
1167 if (strncmp(*s, name, strlen(*s)) == 0)
1168 return 1;
1169 for (s = namelist3; *s; s++)
1170 if (strstr(name, *s) != NULL)
1171 return 1;
1172 return 0;
1173 }
1174
1175 static void read_symbols(char *modname)
1176 {
1177 const char *symname;
1178 char *version;
1179 char *license;
1180 struct module *mod;
1181 struct elf_info info = { };
1182 Elf_Sym *sym;
1183
1184 if (!parse_elf(&info, modname))
1185 return;
1186
1187 mod = new_module(modname);
1188
1189 /* When there's no vmlinux, don't print warnings about
1190 * unresolved symbols (since there'll be too many ;) */
1191 if (is_vmlinux(modname)) {
1192 have_vmlinux = 1;
1193 mod->skip = 1;
1194 }
1195
1196 license = get_modinfo(info.modinfo, info.modinfo_len, "license");
1197 while (license) {
1198 if (license_is_gpl_compatible(license))
1199 mod->gpl_compatible = 1;
1200 else {
1201 mod->gpl_compatible = 0;
1202 break;
1203 }
1204 license = get_next_modinfo(info.modinfo, info.modinfo_len,
1205 "license", license);
1206 }
1207
1208 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
1209 symname = info.strtab + sym->st_name;
1210
1211 handle_modversions(mod, &info, sym, symname);
1212 handle_moddevtable(mod, &info, sym, symname);
1213 }
1214 check_sec_ref(mod, modname, &info, init_section, init_section_ref_ok);
1215 check_sec_ref(mod, modname, &info, exit_section, exit_section_ref_ok);
1216
1217 version = get_modinfo(info.modinfo, info.modinfo_len, "version");
1218 if (version)
1219 maybe_frob_rcs_version(modname, version, info.modinfo,
1220 version - (char *)info.hdr);
1221 if (version || (all_versions && !is_vmlinux(modname)))
1222 get_src_version(modname, mod->srcversion,
1223 sizeof(mod->srcversion)-1);
1224
1225 parse_elf_finish(&info);
1226
1227 /* Our trick to get versioning for struct_module - it's
1228 * never passed as an argument to an exported function, so
1229 * the automatic versioning doesn't pick it up, but it's really
1230 * important anyhow */
1231 if (modversions)
1232 mod->unres = alloc_symbol("struct_module", 0, mod->unres);
1233 }
1234
1235 #define SZ 500
1236
1237 /* We first write the generated file into memory using the
1238 * following helper, then compare to the file on disk and
1239 * only update the later if anything changed */
1240
1241 void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
1242 const char *fmt, ...)
1243 {
1244 char tmp[SZ];
1245 int len;
1246 va_list ap;
1247
1248 va_start(ap, fmt);
1249 len = vsnprintf(tmp, SZ, fmt, ap);
1250 buf_write(buf, tmp, len);
1251 va_end(ap);
1252 }
1253
1254 void buf_write(struct buffer *buf, const char *s, int len)
1255 {
1256 if (buf->size - buf->pos < len) {
1257 buf->size += len + SZ;
1258 buf->p = realloc(buf->p, buf->size);
1259 }
1260 strncpy(buf->p + buf->pos, s, len);
1261 buf->pos += len;
1262 }
1263
1264 static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
1265 {
1266 const char *e = is_vmlinux(m) ?"":".ko";
1267
1268 switch (exp) {
1269 case export_gpl:
1270 fatal("modpost: GPL-incompatible module %s%s "
1271 "uses GPL-only symbol '%s'\n", m, e, s);
1272 break;
1273 case export_unused_gpl:
1274 fatal("modpost: GPL-incompatible module %s%s "
1275 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
1276 break;
1277 case export_gpl_future:
1278 warn("modpost: GPL-incompatible module %s%s "
1279 "uses future GPL-only symbol '%s'\n", m, e, s);
1280 break;
1281 case export_plain:
1282 case export_unused:
1283 case export_unknown:
1284 /* ignore */
1285 break;
1286 }
1287 }
1288
1289 static void check_for_unused(enum export exp, const char* m, const char* s)
1290 {
1291 const char *e = is_vmlinux(m) ?"":".ko";
1292
1293 switch (exp) {
1294 case export_unused:
1295 case export_unused_gpl:
1296 warn("modpost: module %s%s "
1297 "uses symbol '%s' marked UNUSED\n", m, e, s);
1298 break;
1299 default:
1300 /* ignore */
1301 break;
1302 }
1303 }
1304
1305 static void check_exports(struct module *mod)
1306 {
1307 struct symbol *s, *exp;
1308
1309 for (s = mod->unres; s; s = s->next) {
1310 const char *basename;
1311 exp = find_symbol(s->name);
1312 if (!exp || exp->module == mod)
1313 continue;
1314 basename = strrchr(mod->name, '/');
1315 if (basename)
1316 basename++;
1317 else
1318 basename = mod->name;
1319 if (!mod->gpl_compatible)
1320 check_for_gpl_usage(exp->export, basename, exp->name);
1321 check_for_unused(exp->export, basename, exp->name);
1322 }
1323 }
1324
1325 /**
1326 * Header for the generated file
1327 **/
1328 static void add_header(struct buffer *b, struct module *mod)
1329 {
1330 buf_printf(b, "#include <linux/module.h>\n");
1331 buf_printf(b, "#include <linux/vermagic.h>\n");
1332 buf_printf(b, "#include <linux/compiler.h>\n");
1333 buf_printf(b, "\n");
1334 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1335 buf_printf(b, "\n");
1336 buf_printf(b, "struct module __this_module\n");
1337 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
1338 buf_printf(b, " .name = KBUILD_MODNAME,\n");
1339 if (mod->has_init)
1340 buf_printf(b, " .init = init_module,\n");
1341 if (mod->has_cleanup)
1342 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
1343 " .exit = cleanup_module,\n"
1344 "#endif\n");
1345 buf_printf(b, " .arch = MODULE_ARCH_INIT,\n");
1346 buf_printf(b, "};\n");
1347 }
1348
1349 /**
1350 * Record CRCs for unresolved symbols
1351 **/
1352 static int add_versions(struct buffer *b, struct module *mod)
1353 {
1354 struct symbol *s, *exp;
1355 int err = 0;
1356
1357 for (s = mod->unres; s; s = s->next) {
1358 exp = find_symbol(s->name);
1359 if (!exp || exp->module == mod) {
1360 if (have_vmlinux && !s->weak) {
1361 if (warn_unresolved) {
1362 warn("\"%s\" [%s.ko] undefined!\n",
1363 s->name, mod->name);
1364 } else {
1365 merror("\"%s\" [%s.ko] undefined!\n",
1366 s->name, mod->name);
1367 err = 1;
1368 }
1369 }
1370 continue;
1371 }
1372 s->module = exp->module;
1373 s->crc_valid = exp->crc_valid;
1374 s->crc = exp->crc;
1375 }
1376
1377 if (!modversions)
1378 return err;
1379
1380 buf_printf(b, "\n");
1381 buf_printf(b, "static const struct modversion_info ____versions[]\n");
1382 buf_printf(b, "__attribute_used__\n");
1383 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n");
1384
1385 for (s = mod->unres; s; s = s->next) {
1386 if (!s->module) {
1387 continue;
1388 }
1389 if (!s->crc_valid) {
1390 warn("\"%s\" [%s.ko] has no CRC!\n",
1391 s->name, mod->name);
1392 continue;
1393 }
1394 buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name);
1395 }
1396
1397 buf_printf(b, "};\n");
1398
1399 return err;
1400 }
1401
1402 static void add_depends(struct buffer *b, struct module *mod,
1403 struct module *modules)
1404 {
1405 struct symbol *s;
1406 struct module *m;
1407 int first = 1;
1408
1409 for (m = modules; m; m = m->next) {
1410 m->seen = is_vmlinux(m->name);
1411 }
1412
1413 buf_printf(b, "\n");
1414 buf_printf(b, "static const char __module_depends[]\n");
1415 buf_printf(b, "__attribute_used__\n");
1416 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n");
1417 buf_printf(b, "\"depends=");
1418 for (s = mod->unres; s; s = s->next) {
1419 const char *p;
1420 if (!s->module)
1421 continue;
1422
1423 if (s->module->seen)
1424 continue;
1425
1426 s->module->seen = 1;
1427 if ((p = strrchr(s->module->name, '/')) != NULL)
1428 p++;
1429 else
1430 p = s->module->name;
1431 buf_printf(b, "%s%s", first ? "" : ",", p);
1432 first = 0;
1433 }
1434 buf_printf(b, "\";\n");
1435 }
1436
1437 static void add_srcversion(struct buffer *b, struct module *mod)
1438 {
1439 if (mod->srcversion[0]) {
1440 buf_printf(b, "\n");
1441 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
1442 mod->srcversion);
1443 }
1444 }
1445
1446 static void write_if_changed(struct buffer *b, const char *fname)
1447 {
1448 char *tmp;
1449 FILE *file;
1450 struct stat st;
1451
1452 file = fopen(fname, "r");
1453 if (!file)
1454 goto write;
1455
1456 if (fstat(fileno(file), &st) < 0)
1457 goto close_write;
1458
1459 if (st.st_size != b->pos)
1460 goto close_write;
1461
1462 tmp = NOFAIL(malloc(b->pos));
1463 if (fread(tmp, 1, b->pos, file) != b->pos)
1464 goto free_write;
1465
1466 if (memcmp(tmp, b->p, b->pos) != 0)
1467 goto free_write;
1468
1469 free(tmp);
1470 fclose(file);
1471 return;
1472
1473 free_write:
1474 free(tmp);
1475 close_write:
1476 fclose(file);
1477 write:
1478 file = fopen(fname, "w");
1479 if (!file) {
1480 perror(fname);
1481 exit(1);
1482 }
1483 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
1484 perror(fname);
1485 exit(1);
1486 }
1487 fclose(file);
1488 }
1489
1490 /* parse Module.symvers file. line format:
1491 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
1492 **/
1493 static void read_dump(const char *fname, unsigned int kernel)
1494 {
1495 unsigned long size, pos = 0;
1496 void *file = grab_file(fname, &size);
1497 char *line;
1498
1499 if (!file)
1500 /* No symbol versions, silently ignore */
1501 return;
1502
1503 while ((line = get_next_line(&pos, file, size))) {
1504 char *symname, *modname, *d, *export, *end;
1505 unsigned int crc;
1506 struct module *mod;
1507 struct symbol *s;
1508
1509 if (!(symname = strchr(line, '\t')))
1510 goto fail;
1511 *symname++ = '\0';
1512 if (!(modname = strchr(symname, '\t')))
1513 goto fail;
1514 *modname++ = '\0';
1515 if ((export = strchr(modname, '\t')) != NULL)
1516 *export++ = '\0';
1517 if (export && ((end = strchr(export, '\t')) != NULL))
1518 *end = '\0';
1519 crc = strtoul(line, &d, 16);
1520 if (*symname == '\0' || *modname == '\0' || *d != '\0')
1521 goto fail;
1522
1523 if (!(mod = find_module(modname))) {
1524 if (is_vmlinux(modname)) {
1525 have_vmlinux = 1;
1526 }
1527 mod = new_module(NOFAIL(strdup(modname)));
1528 mod->skip = 1;
1529 }
1530 s = sym_add_exported(symname, mod, export_no(export));
1531 s->kernel = kernel;
1532 s->preloaded = 1;
1533 sym_update_crc(symname, mod, crc, export_no(export));
1534 }
1535 return;
1536 fail:
1537 fatal("parse error in symbol dump file\n");
1538 }
1539
1540 /* For normal builds always dump all symbols.
1541 * For external modules only dump symbols
1542 * that are not read from kernel Module.symvers.
1543 **/
1544 static int dump_sym(struct symbol *sym)
1545 {
1546 if (!external_module)
1547 return 1;
1548 if (sym->vmlinux || sym->kernel)
1549 return 0;
1550 return 1;
1551 }
1552
1553 static void write_dump(const char *fname)
1554 {
1555 struct buffer buf = { };
1556 struct symbol *symbol;
1557 int n;
1558
1559 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
1560 symbol = symbolhash[n];
1561 while (symbol) {
1562 if (dump_sym(symbol))
1563 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
1564 symbol->crc, symbol->name,
1565 symbol->module->name,
1566 export_str(symbol->export));
1567 symbol = symbol->next;
1568 }
1569 }
1570 write_if_changed(&buf, fname);
1571 }
1572
1573 int main(int argc, char **argv)
1574 {
1575 struct module *mod;
1576 struct buffer buf = { };
1577 char fname[SZ];
1578 char *kernel_read = NULL, *module_read = NULL;
1579 char *dump_write = NULL;
1580 int opt;
1581 int err;
1582
1583 while ((opt = getopt(argc, argv, "i:I:mo:aw")) != -1) {
1584 switch(opt) {
1585 case 'i':
1586 kernel_read = optarg;
1587 break;
1588 case 'I':
1589 module_read = optarg;
1590 external_module = 1;
1591 break;
1592 case 'm':
1593 modversions = 1;
1594 break;
1595 case 'o':
1596 dump_write = optarg;
1597 break;
1598 case 'a':
1599 all_versions = 1;
1600 break;
1601 case 'w':
1602 warn_unresolved = 1;
1603 break;
1604 default:
1605 exit(1);
1606 }
1607 }
1608
1609 if (kernel_read)
1610 read_dump(kernel_read, 1);
1611 if (module_read)
1612 read_dump(module_read, 0);
1613
1614 while (optind < argc) {
1615 read_symbols(argv[optind++]);
1616 }
1617
1618 for (mod = modules; mod; mod = mod->next) {
1619 if (mod->skip)
1620 continue;
1621 check_exports(mod);
1622 }
1623
1624 err = 0;
1625
1626 for (mod = modules; mod; mod = mod->next) {
1627 if (mod->skip)
1628 continue;
1629
1630 buf.pos = 0;
1631
1632 add_header(&buf, mod);
1633 err |= add_versions(&buf, mod);
1634 add_depends(&buf, mod, modules);
1635 add_moddevtable(&buf, mod);
1636 add_srcversion(&buf, mod);
1637
1638 sprintf(fname, "%s.mod.c", mod->name);
1639 write_if_changed(&buf, fname);
1640 }
1641
1642 if (dump_write)
1643 write_dump(dump_write);
1644
1645 return err;
1646 }
SocketAccessConTroL development