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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 "modpost.h" |
19 | #include "../../include/generated/autoconf.h" |
20 | #include "../../include/linux/license.h" |
21 | |
22 | /* Some toolchains use a `_' prefix for all user symbols. */ |
23 | #ifdef CONFIG_SYMBOL_PREFIX |
24 | #define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX |
25 | #else |
26 | #define MODULE_SYMBOL_PREFIX "" |
27 | #endif |
28 | |
29 | |
30 | /* Are we using CONFIG_MODVERSIONS? */ |
31 | int modversions = 0; |
32 | /* Warn about undefined symbols? (do so if we have vmlinux) */ |
33 | int have_vmlinux = 0; |
34 | /* Is CONFIG_MODULE_SRCVERSION_ALL set? */ |
35 | static int all_versions = 0; |
36 | /* If we are modposting external module set to 1 */ |
37 | static int external_module = 0; |
38 | /* Warn about section mismatch in vmlinux if set to 1 */ |
39 | static int vmlinux_section_warnings = 1; |
40 | /* Only warn about unresolved symbols */ |
41 | static int warn_unresolved = 0; |
42 | /* How a symbol is exported */ |
43 | static int sec_mismatch_count = 0; |
44 | static int sec_mismatch_verbose = 1; |
45 | |
46 | enum export { |
47 | export_plain, export_unused, export_gpl, |
48 | export_unused_gpl, export_gpl_future, export_unknown |
49 | }; |
50 | |
51 | #define PRINTF __attribute__ ((format (printf, 1, 2))) |
52 | |
53 | PRINTF void fatal(const char *fmt, ...) |
54 | { |
55 | va_list arglist; |
56 | |
57 | fprintf(stderr, "FATAL: "); |
58 | |
59 | va_start(arglist, fmt); |
60 | vfprintf(stderr, fmt, arglist); |
61 | va_end(arglist); |
62 | |
63 | exit(1); |
64 | } |
65 | |
66 | PRINTF void warn(const char *fmt, ...) |
67 | { |
68 | va_list arglist; |
69 | |
70 | fprintf(stderr, "WARNING: "); |
71 | |
72 | va_start(arglist, fmt); |
73 | vfprintf(stderr, fmt, arglist); |
74 | va_end(arglist); |
75 | } |
76 | |
77 | PRINTF void merror(const char *fmt, ...) |
78 | { |
79 | va_list arglist; |
80 | |
81 | fprintf(stderr, "ERROR: "); |
82 | |
83 | va_start(arglist, fmt); |
84 | vfprintf(stderr, fmt, arglist); |
85 | va_end(arglist); |
86 | } |
87 | |
88 | static int is_vmlinux(const char *modname) |
89 | { |
90 | const char *myname; |
91 | |
92 | myname = strrchr(modname, '/'); |
93 | if (myname) |
94 | myname++; |
95 | else |
96 | myname = modname; |
97 | |
98 | return (strcmp(myname, "vmlinux") == 0) || |
99 | (strcmp(myname, "vmlinux.o") == 0); |
100 | } |
101 | |
102 | void *do_nofail(void *ptr, const char *expr) |
103 | { |
104 | if (!ptr) |
105 | fatal("modpost: Memory allocation failure: %s.\n", expr); |
106 | |
107 | return ptr; |
108 | } |
109 | |
110 | /* A list of all modules we processed */ |
111 | static struct module *modules; |
112 | |
113 | static struct module *find_module(char *modname) |
114 | { |
115 | struct module *mod; |
116 | |
117 | for (mod = modules; mod; mod = mod->next) |
118 | if (strcmp(mod->name, modname) == 0) |
119 | break; |
120 | return mod; |
121 | } |
122 | |
123 | static struct module *new_module(char *modname) |
124 | { |
125 | struct module *mod; |
126 | char *p, *s; |
127 | |
128 | mod = NOFAIL(malloc(sizeof(*mod))); |
129 | memset(mod, 0, sizeof(*mod)); |
130 | p = NOFAIL(strdup(modname)); |
131 | |
132 | /* strip trailing .o */ |
133 | s = strrchr(p, '.'); |
134 | if (s != NULL) |
135 | if (strcmp(s, ".o") == 0) { |
136 | *s = '\0'; |
137 | mod->is_dot_o = 1; |
138 | } |
139 | |
140 | /* add to list */ |
141 | mod->name = p; |
142 | mod->gpl_compatible = -1; |
143 | mod->next = modules; |
144 | modules = mod; |
145 | |
146 | return mod; |
147 | } |
148 | |
149 | /* A hash of all exported symbols, |
150 | * struct symbol is also used for lists of unresolved symbols */ |
151 | |
152 | #define SYMBOL_HASH_SIZE 1024 |
153 | |
154 | struct symbol { |
155 | struct symbol *next; |
156 | struct module *module; |
157 | unsigned int crc; |
158 | int crc_valid; |
159 | unsigned int weak:1; |
160 | unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */ |
161 | unsigned int kernel:1; /* 1 if symbol is from kernel |
162 | * (only for external modules) **/ |
163 | unsigned int preloaded:1; /* 1 if symbol from Module.symvers */ |
164 | enum export export; /* Type of export */ |
165 | char name[0]; |
166 | }; |
167 | |
168 | static struct symbol *symbolhash[SYMBOL_HASH_SIZE]; |
169 | |
170 | /* This is based on the hash agorithm from gdbm, via tdb */ |
171 | static inline unsigned int tdb_hash(const char *name) |
172 | { |
173 | unsigned value; /* Used to compute the hash value. */ |
174 | unsigned i; /* Used to cycle through random values. */ |
175 | |
176 | /* Set the initial value from the key size. */ |
177 | for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++) |
178 | value = (value + (((unsigned char *)name)[i] << (i*5 % 24))); |
179 | |
180 | return (1103515243 * value + 12345); |
181 | } |
182 | |
183 | /** |
184 | * Allocate a new symbols for use in the hash of exported symbols or |
185 | * the list of unresolved symbols per module |
186 | **/ |
187 | static struct symbol *alloc_symbol(const char *name, unsigned int weak, |
188 | struct symbol *next) |
189 | { |
190 | struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1)); |
191 | |
192 | memset(s, 0, sizeof(*s)); |
193 | strcpy(s->name, name); |
194 | s->weak = weak; |
195 | s->next = next; |
196 | return s; |
197 | } |
198 | |
199 | /* For the hash of exported symbols */ |
200 | static struct symbol *new_symbol(const char *name, struct module *module, |
201 | enum export export) |
202 | { |
203 | unsigned int hash; |
204 | struct symbol *new; |
205 | |
206 | hash = tdb_hash(name) % SYMBOL_HASH_SIZE; |
207 | new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]); |
208 | new->module = module; |
209 | new->export = export; |
210 | return new; |
211 | } |
212 | |
213 | static struct symbol *find_symbol(const char *name) |
214 | { |
215 | struct symbol *s; |
216 | |
217 | /* For our purposes, .foo matches foo. PPC64 needs this. */ |
218 | if (name[0] == '.') |
219 | name++; |
220 | |
221 | for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) { |
222 | if (strcmp(s->name, name) == 0) |
223 | return s; |
224 | } |
225 | return NULL; |
226 | } |
227 | |
228 | static struct { |
229 | const char *str; |
230 | enum export export; |
231 | } export_list[] = { |
232 | { .str = "EXPORT_SYMBOL", .export = export_plain }, |
233 | { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused }, |
234 | { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl }, |
235 | { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl }, |
236 | { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future }, |
237 | { .str = "(unknown)", .export = export_unknown }, |
238 | }; |
239 | |
240 | |
241 | static const char *export_str(enum export ex) |
242 | { |
243 | return export_list[ex].str; |
244 | } |
245 | |
246 | static enum export export_no(const char *s) |
247 | { |
248 | int i; |
249 | |
250 | if (!s) |
251 | return export_unknown; |
252 | for (i = 0; export_list[i].export != export_unknown; i++) { |
253 | if (strcmp(export_list[i].str, s) == 0) |
254 | return export_list[i].export; |
255 | } |
256 | return export_unknown; |
257 | } |
258 | |
259 | static const char *sec_name(struct elf_info *elf, int secindex); |
260 | |
261 | #define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0) |
262 | |
263 | static enum export export_from_secname(struct elf_info *elf, unsigned int sec) |
264 | { |
265 | const char *secname = sec_name(elf, sec); |
266 | |
267 | if (strstarts(secname, "___ksymtab+")) |
268 | return export_plain; |
269 | else if (strstarts(secname, "___ksymtab_unused+")) |
270 | return export_unused; |
271 | else if (strstarts(secname, "___ksymtab_gpl+")) |
272 | return export_gpl; |
273 | else if (strstarts(secname, "___ksymtab_unused_gpl+")) |
274 | return export_unused_gpl; |
275 | else if (strstarts(secname, "___ksymtab_gpl_future+")) |
276 | return export_gpl_future; |
277 | else |
278 | return export_unknown; |
279 | } |
280 | |
281 | static enum export export_from_sec(struct elf_info *elf, unsigned int sec) |
282 | { |
283 | if (sec == elf->export_sec) |
284 | return export_plain; |
285 | else if (sec == elf->export_unused_sec) |
286 | return export_unused; |
287 | else if (sec == elf->export_gpl_sec) |
288 | return export_gpl; |
289 | else if (sec == elf->export_unused_gpl_sec) |
290 | return export_unused_gpl; |
291 | else if (sec == elf->export_gpl_future_sec) |
292 | return export_gpl_future; |
293 | else |
294 | return export_unknown; |
295 | } |
296 | |
297 | /** |
298 | * Add an exported symbol - it may have already been added without a |
299 | * CRC, in this case just update the CRC |
300 | **/ |
301 | static struct symbol *sym_add_exported(const char *name, struct module *mod, |
302 | enum export export) |
303 | { |
304 | struct symbol *s = find_symbol(name); |
305 | |
306 | if (!s) { |
307 | s = new_symbol(name, mod, export); |
308 | } else { |
309 | if (!s->preloaded) { |
310 | warn("%s: '%s' exported twice. Previous export " |
311 | "was in %s%s\n", mod->name, name, |
312 | s->module->name, |
313 | is_vmlinux(s->module->name) ?"":".ko"); |
314 | } else { |
315 | /* In case Modules.symvers was out of date */ |
316 | s->module = mod; |
317 | } |
318 | } |
319 | s->preloaded = 0; |
320 | s->vmlinux = is_vmlinux(mod->name); |
321 | s->kernel = 0; |
322 | s->export = export; |
323 | return s; |
324 | } |
325 | |
326 | static void sym_update_crc(const char *name, struct module *mod, |
327 | unsigned int crc, enum export export) |
328 | { |
329 | struct symbol *s = find_symbol(name); |
330 | |
331 | if (!s) |
332 | s = new_symbol(name, mod, export); |
333 | s->crc = crc; |
334 | s->crc_valid = 1; |
335 | } |
336 | |
337 | void *grab_file(const char *filename, unsigned long *size) |
338 | { |
339 | struct stat st; |
340 | void *map = MAP_FAILED; |
341 | int fd; |
342 | |
343 | fd = open(filename, O_RDONLY); |
344 | if (fd < 0) |
345 | return NULL; |
346 | if (fstat(fd, &st)) |
347 | goto failed; |
348 | |
349 | *size = st.st_size; |
350 | map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); |
351 | |
352 | failed: |
353 | close(fd); |
354 | if (map == MAP_FAILED) |
355 | return NULL; |
356 | return map; |
357 | } |
358 | |
359 | /** |
360 | * Return a copy of the next line in a mmap'ed file. |
361 | * spaces in the beginning of the line is trimmed away. |
362 | * Return a pointer to a static buffer. |
363 | **/ |
364 | char *get_next_line(unsigned long *pos, void *file, unsigned long size) |
365 | { |
366 | static char line[4096]; |
367 | int skip = 1; |
368 | size_t len = 0; |
369 | signed char *p = (signed char *)file + *pos; |
370 | char *s = line; |
371 | |
372 | for (; *pos < size ; (*pos)++) { |
373 | if (skip && isspace(*p)) { |
374 | p++; |
375 | continue; |
376 | } |
377 | skip = 0; |
378 | if (*p != '\n' && (*pos < size)) { |
379 | len++; |
380 | *s++ = *p++; |
381 | if (len > 4095) |
382 | break; /* Too long, stop */ |
383 | } else { |
384 | /* End of string */ |
385 | *s = '\0'; |
386 | return line; |
387 | } |
388 | } |
389 | /* End of buffer */ |
390 | return NULL; |
391 | } |
392 | |
393 | void release_file(void *file, unsigned long size) |
394 | { |
395 | munmap(file, size); |
396 | } |
397 | |
398 | static int parse_elf(struct elf_info *info, const char *filename) |
399 | { |
400 | unsigned int i; |
401 | Elf_Ehdr *hdr; |
402 | Elf_Shdr *sechdrs; |
403 | Elf_Sym *sym; |
404 | const char *secstrings; |
405 | unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U; |
406 | |
407 | hdr = grab_file(filename, &info->size); |
408 | if (!hdr) { |
409 | perror(filename); |
410 | exit(1); |
411 | } |
412 | info->hdr = hdr; |
413 | if (info->size < sizeof(*hdr)) { |
414 | /* file too small, assume this is an empty .o file */ |
415 | return 0; |
416 | } |
417 | /* Is this a valid ELF file? */ |
418 | if ((hdr->e_ident[EI_MAG0] != ELFMAG0) || |
419 | (hdr->e_ident[EI_MAG1] != ELFMAG1) || |
420 | (hdr->e_ident[EI_MAG2] != ELFMAG2) || |
421 | (hdr->e_ident[EI_MAG3] != ELFMAG3)) { |
422 | /* Not an ELF file - silently ignore it */ |
423 | return 0; |
424 | } |
425 | /* Fix endianness in ELF header */ |
426 | hdr->e_type = TO_NATIVE(hdr->e_type); |
427 | hdr->e_machine = TO_NATIVE(hdr->e_machine); |
428 | hdr->e_version = TO_NATIVE(hdr->e_version); |
429 | hdr->e_entry = TO_NATIVE(hdr->e_entry); |
430 | hdr->e_phoff = TO_NATIVE(hdr->e_phoff); |
431 | hdr->e_shoff = TO_NATIVE(hdr->e_shoff); |
432 | hdr->e_flags = TO_NATIVE(hdr->e_flags); |
433 | hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize); |
434 | hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize); |
435 | hdr->e_phnum = TO_NATIVE(hdr->e_phnum); |
436 | hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize); |
437 | hdr->e_shnum = TO_NATIVE(hdr->e_shnum); |
438 | hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx); |
439 | sechdrs = (void *)hdr + hdr->e_shoff; |
440 | info->sechdrs = sechdrs; |
441 | |
442 | /* Check if file offset is correct */ |
443 | if (hdr->e_shoff > info->size) { |
444 | fatal("section header offset=%lu in file '%s' is bigger than " |
445 | "filesize=%lu\n", (unsigned long)hdr->e_shoff, |
446 | filename, info->size); |
447 | return 0; |
448 | } |
449 | |
450 | if (hdr->e_shnum == SHN_UNDEF) { |
451 | /* |
452 | * There are more than 64k sections, |
453 | * read count from .sh_size. |
454 | */ |
455 | info->num_sections = TO_NATIVE(sechdrs[0].sh_size); |
456 | } |
457 | else { |
458 | info->num_sections = hdr->e_shnum; |
459 | } |
460 | if (hdr->e_shstrndx == SHN_XINDEX) { |
461 | info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link); |
462 | } |
463 | else { |
464 | info->secindex_strings = hdr->e_shstrndx; |
465 | } |
466 | |
467 | /* Fix endianness in section headers */ |
468 | for (i = 0; i < info->num_sections; i++) { |
469 | sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name); |
470 | sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type); |
471 | sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags); |
472 | sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr); |
473 | sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset); |
474 | sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size); |
475 | sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link); |
476 | sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info); |
477 | sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign); |
478 | sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize); |
479 | } |
480 | /* Find symbol table. */ |
481 | secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset; |
482 | for (i = 1; i < info->num_sections; i++) { |
483 | const char *secname; |
484 | int nobits = sechdrs[i].sh_type == SHT_NOBITS; |
485 | |
486 | if (!nobits && sechdrs[i].sh_offset > info->size) { |
487 | fatal("%s is truncated. sechdrs[i].sh_offset=%lu > " |
488 | "sizeof(*hrd)=%zu\n", filename, |
489 | (unsigned long)sechdrs[i].sh_offset, |
490 | sizeof(*hdr)); |
491 | return 0; |
492 | } |
493 | secname = secstrings + sechdrs[i].sh_name; |
494 | if (strcmp(secname, ".modinfo") == 0) { |
495 | if (nobits) |
496 | fatal("%s has NOBITS .modinfo\n", filename); |
497 | info->modinfo = (void *)hdr + sechdrs[i].sh_offset; |
498 | info->modinfo_len = sechdrs[i].sh_size; |
499 | } else if (strcmp(secname, "__ksymtab") == 0) |
500 | info->export_sec = i; |
501 | else if (strcmp(secname, "__ksymtab_unused") == 0) |
502 | info->export_unused_sec = i; |
503 | else if (strcmp(secname, "__ksymtab_gpl") == 0) |
504 | info->export_gpl_sec = i; |
505 | else if (strcmp(secname, "__ksymtab_unused_gpl") == 0) |
506 | info->export_unused_gpl_sec = i; |
507 | else if (strcmp(secname, "__ksymtab_gpl_future") == 0) |
508 | info->export_gpl_future_sec = i; |
509 | |
510 | if (sechdrs[i].sh_type == SHT_SYMTAB) { |
511 | unsigned int sh_link_idx; |
512 | symtab_idx = i; |
513 | info->symtab_start = (void *)hdr + |
514 | sechdrs[i].sh_offset; |
515 | info->symtab_stop = (void *)hdr + |
516 | sechdrs[i].sh_offset + sechdrs[i].sh_size; |
517 | sh_link_idx = sechdrs[i].sh_link; |
518 | info->strtab = (void *)hdr + |
519 | sechdrs[sh_link_idx].sh_offset; |
520 | } |
521 | |
522 | /* 32bit section no. table? ("more than 64k sections") */ |
523 | if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) { |
524 | symtab_shndx_idx = i; |
525 | info->symtab_shndx_start = (void *)hdr + |
526 | sechdrs[i].sh_offset; |
527 | info->symtab_shndx_stop = (void *)hdr + |
528 | sechdrs[i].sh_offset + sechdrs[i].sh_size; |
529 | } |
530 | } |
531 | if (!info->symtab_start) |
532 | fatal("%s has no symtab?\n", filename); |
533 | |
534 | /* Fix endianness in symbols */ |
535 | for (sym = info->symtab_start; sym < info->symtab_stop; sym++) { |
536 | sym->st_shndx = TO_NATIVE(sym->st_shndx); |
537 | sym->st_name = TO_NATIVE(sym->st_name); |
538 | sym->st_value = TO_NATIVE(sym->st_value); |
539 | sym->st_size = TO_NATIVE(sym->st_size); |
540 | } |
541 | |
542 | if (symtab_shndx_idx != ~0U) { |
543 | Elf32_Word *p; |
544 | if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link) |
545 | fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n", |
546 | filename, sechdrs[symtab_shndx_idx].sh_link, |
547 | symtab_idx); |
548 | /* Fix endianness */ |
549 | for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop; |
550 | p++) |
551 | *p = TO_NATIVE(*p); |
552 | } |
553 | |
554 | return 1; |
555 | } |
556 | |
557 | static void parse_elf_finish(struct elf_info *info) |
558 | { |
559 | release_file(info->hdr, info->size); |
560 | } |
561 | |
562 | static int ignore_undef_symbol(struct elf_info *info, const char *symname) |
563 | { |
564 | /* ignore __this_module, it will be resolved shortly */ |
565 | if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0) |
566 | return 1; |
567 | /* ignore global offset table */ |
568 | if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0) |
569 | return 1; |
570 | if (info->hdr->e_machine == EM_PPC) |
571 | /* Special register function linked on all modules during final link of .ko */ |
572 | if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 || |
573 | strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 || |
574 | strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 || |
575 | strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0) |
576 | return 1; |
577 | if (info->hdr->e_machine == EM_PPC64) |
578 | /* Special register function linked on all modules during final link of .ko */ |
579 | if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 || |
580 | strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0) |
581 | return 1; |
582 | /* Do not ignore this symbol */ |
583 | return 0; |
584 | } |
585 | |
586 | #define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_" |
587 | #define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_" |
588 | |
589 | static void handle_modversions(struct module *mod, struct elf_info *info, |
590 | Elf_Sym *sym, const char *symname) |
591 | { |
592 | unsigned int crc; |
593 | enum export export; |
594 | |
595 | if ((!is_vmlinux(mod->name) || mod->is_dot_o) && |
596 | strncmp(symname, "__ksymtab", 9) == 0) |
597 | export = export_from_secname(info, get_secindex(info, sym)); |
598 | else |
599 | export = export_from_sec(info, get_secindex(info, sym)); |
600 | |
601 | switch (sym->st_shndx) { |
602 | case SHN_COMMON: |
603 | warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name); |
604 | break; |
605 | case SHN_ABS: |
606 | /* CRC'd symbol */ |
607 | if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) { |
608 | crc = (unsigned int) sym->st_value; |
609 | sym_update_crc(symname + strlen(CRC_PFX), mod, crc, |
610 | export); |
611 | } |
612 | break; |
613 | case SHN_UNDEF: |
614 | /* undefined symbol */ |
615 | if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && |
616 | ELF_ST_BIND(sym->st_info) != STB_WEAK) |
617 | break; |
618 | if (ignore_undef_symbol(info, symname)) |
619 | break; |
620 | /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */ |
621 | #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER) |
622 | /* add compatibility with older glibc */ |
623 | #ifndef STT_SPARC_REGISTER |
624 | #define STT_SPARC_REGISTER STT_REGISTER |
625 | #endif |
626 | if (info->hdr->e_machine == EM_SPARC || |
627 | info->hdr->e_machine == EM_SPARCV9) { |
628 | /* Ignore register directives. */ |
629 | if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER) |
630 | break; |
631 | if (symname[0] == '.') { |
632 | char *munged = strdup(symname); |
633 | munged[0] = '_'; |
634 | munged[1] = toupper(munged[1]); |
635 | symname = munged; |
636 | } |
637 | } |
638 | #endif |
639 | |
640 | if (memcmp(symname, MODULE_SYMBOL_PREFIX, |
641 | strlen(MODULE_SYMBOL_PREFIX)) == 0) { |
642 | mod->unres = |
643 | alloc_symbol(symname + |
644 | strlen(MODULE_SYMBOL_PREFIX), |
645 | ELF_ST_BIND(sym->st_info) == STB_WEAK, |
646 | mod->unres); |
647 | } |
648 | break; |
649 | default: |
650 | /* All exported symbols */ |
651 | if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) { |
652 | sym_add_exported(symname + strlen(KSYMTAB_PFX), mod, |
653 | export); |
654 | } |
655 | if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0) |
656 | mod->has_init = 1; |
657 | if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0) |
658 | mod->has_cleanup = 1; |
659 | break; |
660 | } |
661 | } |
662 | |
663 | /** |
664 | * Parse tag=value strings from .modinfo section |
665 | **/ |
666 | static char *next_string(char *string, unsigned long *secsize) |
667 | { |
668 | /* Skip non-zero chars */ |
669 | while (string[0]) { |
670 | string++; |
671 | if ((*secsize)-- <= 1) |
672 | return NULL; |
673 | } |
674 | |
675 | /* Skip any zero padding. */ |
676 | while (!string[0]) { |
677 | string++; |
678 | if ((*secsize)-- <= 1) |
679 | return NULL; |
680 | } |
681 | return string; |
682 | } |
683 | |
684 | static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len, |
685 | const char *tag, char *info) |
686 | { |
687 | char *p; |
688 | unsigned int taglen = strlen(tag); |
689 | unsigned long size = modinfo_len; |
690 | |
691 | if (info) { |
692 | size -= info - (char *)modinfo; |
693 | modinfo = next_string(info, &size); |
694 | } |
695 | |
696 | for (p = modinfo; p; p = next_string(p, &size)) { |
697 | if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') |
698 | return p + taglen + 1; |
699 | } |
700 | return NULL; |
701 | } |
702 | |
703 | static char *get_modinfo(void *modinfo, unsigned long modinfo_len, |
704 | const char *tag) |
705 | |
706 | { |
707 | return get_next_modinfo(modinfo, modinfo_len, tag, NULL); |
708 | } |
709 | |
710 | /** |
711 | * Test if string s ends in string sub |
712 | * return 0 if match |
713 | **/ |
714 | static int strrcmp(const char *s, const char *sub) |
715 | { |
716 | int slen, sublen; |
717 | |
718 | if (!s || !sub) |
719 | return 1; |
720 | |
721 | slen = strlen(s); |
722 | sublen = strlen(sub); |
723 | |
724 | if ((slen == 0) || (sublen == 0)) |
725 | return 1; |
726 | |
727 | if (sublen > slen) |
728 | return 1; |
729 | |
730 | return memcmp(s + slen - sublen, sub, sublen); |
731 | } |
732 | |
733 | static const char *sym_name(struct elf_info *elf, Elf_Sym *sym) |
734 | { |
735 | if (sym) |
736 | return elf->strtab + sym->st_name; |
737 | else |
738 | return "(unknown)"; |
739 | } |
740 | |
741 | static const char *sec_name(struct elf_info *elf, int secindex) |
742 | { |
743 | Elf_Shdr *sechdrs = elf->sechdrs; |
744 | return (void *)elf->hdr + |
745 | elf->sechdrs[elf->secindex_strings].sh_offset + |
746 | sechdrs[secindex].sh_name; |
747 | } |
748 | |
749 | static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr) |
750 | { |
751 | return (void *)elf->hdr + |
752 | elf->sechdrs[elf->secindex_strings].sh_offset + |
753 | sechdr->sh_name; |
754 | } |
755 | |
756 | /* if sym is empty or point to a string |
757 | * like ".[0-9]+" then return 1. |
758 | * This is the optional prefix added by ld to some sections |
759 | */ |
760 | static int number_prefix(const char *sym) |
761 | { |
762 | if (*sym++ == '\0') |
763 | return 1; |
764 | if (*sym != '.') |
765 | return 0; |
766 | do { |
767 | char c = *sym++; |
768 | if (c < '0' || c > '9') |
769 | return 0; |
770 | } while (*sym); |
771 | return 1; |
772 | } |
773 | |
774 | /* The pattern is an array of simple patterns. |
775 | * "foo" will match an exact string equal to "foo" |
776 | * "*foo" will match a string that ends with "foo" |
777 | * "foo*" will match a string that begins with "foo" |
778 | * "foo$" will match a string equal to "foo" or "foo.1" |
779 | * where the '1' can be any number including several digits. |
780 | * The $ syntax is for sections where ld append a dot number |
781 | * to make section name unique. |
782 | */ |
783 | static int match(const char *sym, const char * const pat[]) |
784 | { |
785 | const char *p; |
786 | while (*pat) { |
787 | p = *pat++; |
788 | const char *endp = p + strlen(p) - 1; |
789 | |
790 | /* "*foo" */ |
791 | if (*p == '*') { |
792 | if (strrcmp(sym, p + 1) == 0) |
793 | return 1; |
794 | } |
795 | /* "foo*" */ |
796 | else if (*endp == '*') { |
797 | if (strncmp(sym, p, strlen(p) - 1) == 0) |
798 | return 1; |
799 | } |
800 | /* "foo$" */ |
801 | else if (*endp == '$') { |
802 | if (strncmp(sym, p, strlen(p) - 1) == 0) { |
803 | if (number_prefix(sym + strlen(p) - 1)) |
804 | return 1; |
805 | } |
806 | } |
807 | /* no wildcards */ |
808 | else { |
809 | if (strcmp(p, sym) == 0) |
810 | return 1; |
811 | } |
812 | } |
813 | /* no match */ |
814 | return 0; |
815 | } |
816 | |
817 | /* sections that we do not want to do full section mismatch check on */ |
818 | static const char *section_white_list[] = |
819 | { |
820 | ".comment*", |
821 | ".debug*", |
822 | ".zdebug*", /* Compressed debug sections. */ |
823 | ".GCC-command-line", /* mn10300 */ |
824 | ".GCC.command.line", /* record-gcc-switches, non mn10300 */ |
825 | ".mdebug*", /* alpha, score, mips etc. */ |
826 | ".pdr", /* alpha, score, mips etc. */ |
827 | ".stab*", |
828 | ".note*", |
829 | ".got*", |
830 | ".toc*", |
831 | ".xt.prop", /* xtensa */ |
832 | ".xt.lit", /* xtensa */ |
833 | ".arcextmap*", /* arc */ |
834 | ".gnu.linkonce.arcext*", /* arc : modules */ |
835 | NULL |
836 | }; |
837 | |
838 | /* |
839 | * This is used to find sections missing the SHF_ALLOC flag. |
840 | * The cause of this is often a section specified in assembler |
841 | * without "ax" / "aw". |
842 | */ |
843 | static void check_section(const char *modname, struct elf_info *elf, |
844 | Elf_Shdr *sechdr) |
845 | { |
846 | const char *sec = sech_name(elf, sechdr); |
847 | |
848 | if (sechdr->sh_type == SHT_PROGBITS && |
849 | !(sechdr->sh_flags & SHF_ALLOC) && |
850 | !match(sec, section_white_list)) { |
851 | warn("%s (%s): unexpected non-allocatable section.\n" |
852 | "Did you forget to use \"ax\"/\"aw\" in a .S file?\n" |
853 | "Note that for example <linux/init.h> contains\n" |
854 | "section definitions for use in .S files.\n\n", |
855 | modname, sec); |
856 | } |
857 | } |
858 | |
859 | |
860 | |
861 | #define ALL_INIT_DATA_SECTIONS \ |
862 | ".init.setup$", ".init.rodata$", \ |
863 | ".cpuinit.rodata$", ".meminit.rodata$", \ |
864 | ".init.data$", ".cpuinit.data$", ".meminit.data$" |
865 | #define ALL_EXIT_DATA_SECTIONS \ |
866 | ".exit.data$", ".cpuexit.data$", ".memexit.data$" |
867 | |
868 | #define ALL_INIT_TEXT_SECTIONS \ |
869 | ".init.text$", ".cpuinit.text$", ".meminit.text$" |
870 | #define ALL_EXIT_TEXT_SECTIONS \ |
871 | ".exit.text$", ".cpuexit.text$", ".memexit.text$" |
872 | |
873 | #define ALL_PCI_INIT_SECTIONS \ |
874 | ".pci_fixup_early$", ".pci_fixup_header$", ".pci_fixup_final$", \ |
875 | ".pci_fixup_enable$", ".pci_fixup_resume$", \ |
876 | ".pci_fixup_resume_early$", ".pci_fixup_suspend$" |
877 | |
878 | #define ALL_XXXINIT_SECTIONS CPU_INIT_SECTIONS, MEM_INIT_SECTIONS |
879 | #define ALL_XXXEXIT_SECTIONS CPU_EXIT_SECTIONS, MEM_EXIT_SECTIONS |
880 | |
881 | #define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS |
882 | #define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS |
883 | |
884 | #define DATA_SECTIONS ".data$", ".data.rel$" |
885 | #define TEXT_SECTIONS ".text$" |
886 | |
887 | #define INIT_SECTIONS ".init.*" |
888 | #define CPU_INIT_SECTIONS ".cpuinit.*" |
889 | #define MEM_INIT_SECTIONS ".meminit.*" |
890 | |
891 | #define EXIT_SECTIONS ".exit.*" |
892 | #define CPU_EXIT_SECTIONS ".cpuexit.*" |
893 | #define MEM_EXIT_SECTIONS ".memexit.*" |
894 | |
895 | /* init data sections */ |
896 | static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL }; |
897 | |
898 | /* all init sections */ |
899 | static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL }; |
900 | |
901 | /* All init and exit sections (code + data) */ |
902 | static const char *init_exit_sections[] = |
903 | {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL }; |
904 | |
905 | /* data section */ |
906 | static const char *data_sections[] = { DATA_SECTIONS, NULL }; |
907 | |
908 | |
909 | /* symbols in .data that may refer to init/exit sections */ |
910 | #define DEFAULT_SYMBOL_WHITE_LIST \ |
911 | "*driver", \ |
912 | "*_template", /* scsi uses *_template a lot */ \ |
913 | "*_timer", /* arm uses ops structures named _timer a lot */ \ |
914 | "*_sht", /* scsi also used *_sht to some extent */ \ |
915 | "*_ops", \ |
916 | "*_probe", \ |
917 | "*_probe_one", \ |
918 | "*_console" |
919 | |
920 | static const char *head_sections[] = { ".head.text*", NULL }; |
921 | static const char *linker_symbols[] = |
922 | { "__init_begin", "_sinittext", "_einittext", NULL }; |
923 | |
924 | enum mismatch { |
925 | TEXT_TO_ANY_INIT, |
926 | DATA_TO_ANY_INIT, |
927 | TEXT_TO_ANY_EXIT, |
928 | DATA_TO_ANY_EXIT, |
929 | XXXINIT_TO_SOME_INIT, |
930 | XXXEXIT_TO_SOME_EXIT, |
931 | ANY_INIT_TO_ANY_EXIT, |
932 | ANY_EXIT_TO_ANY_INIT, |
933 | EXPORT_TO_INIT_EXIT, |
934 | }; |
935 | |
936 | struct sectioncheck { |
937 | const char *fromsec[20]; |
938 | const char *tosec[20]; |
939 | enum mismatch mismatch; |
940 | const char *symbol_white_list[20]; |
941 | }; |
942 | |
943 | const struct sectioncheck sectioncheck[] = { |
944 | /* Do not reference init/exit code/data from |
945 | * normal code and data |
946 | */ |
947 | { |
948 | .fromsec = { TEXT_SECTIONS, NULL }, |
949 | .tosec = { ALL_INIT_SECTIONS, NULL }, |
950 | .mismatch = TEXT_TO_ANY_INIT, |
951 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
952 | }, |
953 | { |
954 | .fromsec = { DATA_SECTIONS, NULL }, |
955 | .tosec = { ALL_XXXINIT_SECTIONS, NULL }, |
956 | .mismatch = DATA_TO_ANY_INIT, |
957 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
958 | }, |
959 | { |
960 | .fromsec = { DATA_SECTIONS, NULL }, |
961 | .tosec = { INIT_SECTIONS, NULL }, |
962 | .mismatch = DATA_TO_ANY_INIT, |
963 | .symbol_white_list = { |
964 | "*_template", "*_timer", "*_sht", "*_ops", |
965 | "*_probe", "*_probe_one", "*_console", NULL |
966 | }, |
967 | }, |
968 | { |
969 | .fromsec = { TEXT_SECTIONS, NULL }, |
970 | .tosec = { ALL_EXIT_SECTIONS, NULL }, |
971 | .mismatch = TEXT_TO_ANY_EXIT, |
972 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
973 | }, |
974 | { |
975 | .fromsec = { DATA_SECTIONS, NULL }, |
976 | .tosec = { ALL_EXIT_SECTIONS, NULL }, |
977 | .mismatch = DATA_TO_ANY_EXIT, |
978 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
979 | }, |
980 | /* Do not reference init code/data from cpuinit/meminit code/data */ |
981 | { |
982 | .fromsec = { ALL_XXXINIT_SECTIONS, NULL }, |
983 | .tosec = { INIT_SECTIONS, NULL }, |
984 | .mismatch = XXXINIT_TO_SOME_INIT, |
985 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
986 | }, |
987 | /* Do not reference cpuinit code/data from meminit code/data */ |
988 | { |
989 | .fromsec = { MEM_INIT_SECTIONS, NULL }, |
990 | .tosec = { CPU_INIT_SECTIONS, NULL }, |
991 | .mismatch = XXXINIT_TO_SOME_INIT, |
992 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
993 | }, |
994 | /* Do not reference meminit code/data from cpuinit code/data */ |
995 | { |
996 | .fromsec = { CPU_INIT_SECTIONS, NULL }, |
997 | .tosec = { MEM_INIT_SECTIONS, NULL }, |
998 | .mismatch = XXXINIT_TO_SOME_INIT, |
999 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
1000 | }, |
1001 | /* Do not reference exit code/data from cpuexit/memexit code/data */ |
1002 | { |
1003 | .fromsec = { ALL_XXXEXIT_SECTIONS, NULL }, |
1004 | .tosec = { EXIT_SECTIONS, NULL }, |
1005 | .mismatch = XXXEXIT_TO_SOME_EXIT, |
1006 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
1007 | }, |
1008 | /* Do not reference cpuexit code/data from memexit code/data */ |
1009 | { |
1010 | .fromsec = { MEM_EXIT_SECTIONS, NULL }, |
1011 | .tosec = { CPU_EXIT_SECTIONS, NULL }, |
1012 | .mismatch = XXXEXIT_TO_SOME_EXIT, |
1013 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
1014 | }, |
1015 | /* Do not reference memexit code/data from cpuexit code/data */ |
1016 | { |
1017 | .fromsec = { CPU_EXIT_SECTIONS, NULL }, |
1018 | .tosec = { MEM_EXIT_SECTIONS, NULL }, |
1019 | .mismatch = XXXEXIT_TO_SOME_EXIT, |
1020 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
1021 | }, |
1022 | /* Do not use exit code/data from init code */ |
1023 | { |
1024 | .fromsec = { ALL_INIT_SECTIONS, NULL }, |
1025 | .tosec = { ALL_EXIT_SECTIONS, NULL }, |
1026 | .mismatch = ANY_INIT_TO_ANY_EXIT, |
1027 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
1028 | }, |
1029 | /* Do not use init code/data from exit code */ |
1030 | { |
1031 | .fromsec = { ALL_EXIT_SECTIONS, NULL }, |
1032 | .tosec = { ALL_INIT_SECTIONS, NULL }, |
1033 | .mismatch = ANY_EXIT_TO_ANY_INIT, |
1034 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
1035 | }, |
1036 | { |
1037 | .fromsec = { ALL_PCI_INIT_SECTIONS, NULL }, |
1038 | .tosec = { INIT_SECTIONS, NULL }, |
1039 | .mismatch = ANY_INIT_TO_ANY_EXIT, |
1040 | .symbol_white_list = { NULL }, |
1041 | }, |
1042 | /* Do not export init/exit functions or data */ |
1043 | { |
1044 | .fromsec = { "__ksymtab*", NULL }, |
1045 | .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL }, |
1046 | .mismatch = EXPORT_TO_INIT_EXIT, |
1047 | .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, |
1048 | } |
1049 | }; |
1050 | |
1051 | static const struct sectioncheck *section_mismatch( |
1052 | const char *fromsec, const char *tosec) |
1053 | { |
1054 | int i; |
1055 | int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck); |
1056 | const struct sectioncheck *check = §ioncheck[0]; |
1057 | |
1058 | for (i = 0; i < elems; i++) { |
1059 | if (match(fromsec, check->fromsec) && |
1060 | match(tosec, check->tosec)) |
1061 | return check; |
1062 | check++; |
1063 | } |
1064 | return NULL; |
1065 | } |
1066 | |
1067 | /** |
1068 | * Whitelist to allow certain references to pass with no warning. |
1069 | * |
1070 | * Pattern 1: |
1071 | * If a module parameter is declared __initdata and permissions=0 |
1072 | * then this is legal despite the warning generated. |
1073 | * We cannot see value of permissions here, so just ignore |
1074 | * this pattern. |
1075 | * The pattern is identified by: |
1076 | * tosec = .init.data |
1077 | * fromsec = .data* |
1078 | * atsym =__param* |
1079 | * |
1080 | * Pattern 1a: |
1081 | * module_param_call() ops can refer to __init set function if permissions=0 |
1082 | * The pattern is identified by: |
1083 | * tosec = .init.text |
1084 | * fromsec = .data* |
1085 | * atsym = __param_ops_* |
1086 | * |
1087 | * Pattern 2: |
1088 | * Many drivers utilise a *driver container with references to |
1089 | * add, remove, probe functions etc. |
1090 | * These functions may often be marked __cpuinit and we do not want to |
1091 | * warn here. |
1092 | * the pattern is identified by: |
1093 | * tosec = init or exit section |
1094 | * fromsec = data section |
1095 | * atsym = *driver, *_template, *_sht, *_ops, *_probe, |
1096 | * *probe_one, *_console, *_timer |
1097 | * |
1098 | * Pattern 3: |
1099 | * Whitelist all references from .head.text to any init section |
1100 | * |
1101 | * Pattern 4: |
1102 | * Some symbols belong to init section but still it is ok to reference |
1103 | * these from non-init sections as these symbols don't have any memory |
1104 | * allocated for them and symbol address and value are same. So even |
1105 | * if init section is freed, its ok to reference those symbols. |
1106 | * For ex. symbols marking the init section boundaries. |
1107 | * This pattern is identified by |
1108 | * refsymname = __init_begin, _sinittext, _einittext |
1109 | * |
1110 | **/ |
1111 | static int secref_whitelist(const struct sectioncheck *mismatch, |
1112 | const char *fromsec, const char *fromsym, |
1113 | const char *tosec, const char *tosym) |
1114 | { |
1115 | /* Check for pattern 1 */ |
1116 | if (match(tosec, init_data_sections) && |
1117 | match(fromsec, data_sections) && |
1118 | (strncmp(fromsym, "__param", strlen("__param")) == 0)) |
1119 | return 0; |
1120 | |
1121 | /* Check for pattern 1a */ |
1122 | if (strcmp(tosec, ".init.text") == 0 && |
1123 | match(fromsec, data_sections) && |
1124 | (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0)) |
1125 | return 0; |
1126 | |
1127 | /* Check for pattern 2 */ |
1128 | if (match(tosec, init_exit_sections) && |
1129 | match(fromsec, data_sections) && |
1130 | match(fromsym, mismatch->symbol_white_list)) |
1131 | return 0; |
1132 | |
1133 | /* Check for pattern 3 */ |
1134 | if (match(fromsec, head_sections) && |
1135 | match(tosec, init_sections)) |
1136 | return 0; |
1137 | |
1138 | /* Check for pattern 4 */ |
1139 | if (match(tosym, linker_symbols)) |
1140 | return 0; |
1141 | |
1142 | return 1; |
1143 | } |
1144 | |
1145 | /** |
1146 | * Find symbol based on relocation record info. |
1147 | * In some cases the symbol supplied is a valid symbol so |
1148 | * return refsym. If st_name != 0 we assume this is a valid symbol. |
1149 | * In other cases the symbol needs to be looked up in the symbol table |
1150 | * based on section and address. |
1151 | * **/ |
1152 | static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr, |
1153 | Elf_Sym *relsym) |
1154 | { |
1155 | Elf_Sym *sym; |
1156 | Elf_Sym *near = NULL; |
1157 | Elf64_Sword distance = 20; |
1158 | Elf64_Sword d; |
1159 | unsigned int relsym_secindex; |
1160 | |
1161 | if (relsym->st_name != 0) |
1162 | return relsym; |
1163 | |
1164 | relsym_secindex = get_secindex(elf, relsym); |
1165 | for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { |
1166 | if (get_secindex(elf, sym) != relsym_secindex) |
1167 | continue; |
1168 | if (ELF_ST_TYPE(sym->st_info) == STT_SECTION) |
1169 | continue; |
1170 | if (sym->st_value == addr) |
1171 | return sym; |
1172 | /* Find a symbol nearby - addr are maybe negative */ |
1173 | d = sym->st_value - addr; |
1174 | if (d < 0) |
1175 | d = addr - sym->st_value; |
1176 | if (d < distance) { |
1177 | distance = d; |
1178 | near = sym; |
1179 | } |
1180 | } |
1181 | /* We need a close match */ |
1182 | if (distance < 20) |
1183 | return near; |
1184 | else |
1185 | return NULL; |
1186 | } |
1187 | |
1188 | static inline int is_arm_mapping_symbol(const char *str) |
1189 | { |
1190 | return str[0] == '$' && strchr("atd", str[1]) |
1191 | && (str[2] == '\0' || str[2] == '.'); |
1192 | } |
1193 | |
1194 | /* |
1195 | * If there's no name there, ignore it; likewise, ignore it if it's |
1196 | * one of the magic symbols emitted used by current ARM tools. |
1197 | * |
1198 | * Otherwise if find_symbols_between() returns those symbols, they'll |
1199 | * fail the whitelist tests and cause lots of false alarms ... fixable |
1200 | * only by merging __exit and __init sections into __text, bloating |
1201 | * the kernel (which is especially evil on embedded platforms). |
1202 | */ |
1203 | static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym) |
1204 | { |
1205 | const char *name = elf->strtab + sym->st_name; |
1206 | |
1207 | if (!name || !strlen(name)) |
1208 | return 0; |
1209 | return !is_arm_mapping_symbol(name); |
1210 | } |
1211 | |
1212 | /* |
1213 | * Find symbols before or equal addr and after addr - in the section sec. |
1214 | * If we find two symbols with equal offset prefer one with a valid name. |
1215 | * The ELF format may have a better way to detect what type of symbol |
1216 | * it is, but this works for now. |
1217 | **/ |
1218 | static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr, |
1219 | const char *sec) |
1220 | { |
1221 | Elf_Sym *sym; |
1222 | Elf_Sym *near = NULL; |
1223 | Elf_Addr distance = ~0; |
1224 | |
1225 | for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { |
1226 | const char *symsec; |
1227 | |
1228 | if (is_shndx_special(sym->st_shndx)) |
1229 | continue; |
1230 | symsec = sec_name(elf, get_secindex(elf, sym)); |
1231 | if (strcmp(symsec, sec) != 0) |
1232 | continue; |
1233 | if (!is_valid_name(elf, sym)) |
1234 | continue; |
1235 | if (sym->st_value <= addr) { |
1236 | if ((addr - sym->st_value) < distance) { |
1237 | distance = addr - sym->st_value; |
1238 | near = sym; |
1239 | } else if ((addr - sym->st_value) == distance) { |
1240 | near = sym; |
1241 | } |
1242 | } |
1243 | } |
1244 | return near; |
1245 | } |
1246 | |
1247 | /* |
1248 | * Convert a section name to the function/data attribute |
1249 | * .init.text => __init |
1250 | * .cpuinit.data => __cpudata |
1251 | * .memexitconst => __memconst |
1252 | * etc. |
1253 | * |
1254 | * The memory of returned value has been allocated on a heap. The user of this |
1255 | * method should free it after usage. |
1256 | */ |
1257 | static char *sec2annotation(const char *s) |
1258 | { |
1259 | if (match(s, init_exit_sections)) { |
1260 | char *p = malloc(20); |
1261 | char *r = p; |
1262 | |
1263 | *p++ = '_'; |
1264 | *p++ = '_'; |
1265 | if (*s == '.') |
1266 | s++; |
1267 | while (*s && *s != '.') |
1268 | *p++ = *s++; |
1269 | *p = '\0'; |
1270 | if (*s == '.') |
1271 | s++; |
1272 | if (strstr(s, "rodata") != NULL) |
1273 | strcat(p, "const "); |
1274 | else if (strstr(s, "data") != NULL) |
1275 | strcat(p, "data "); |
1276 | else |
1277 | strcat(p, " "); |
1278 | return r; |
1279 | } else { |
1280 | return strdup(""); |
1281 | } |
1282 | } |
1283 | |
1284 | static int is_function(Elf_Sym *sym) |
1285 | { |
1286 | if (sym) |
1287 | return ELF_ST_TYPE(sym->st_info) == STT_FUNC; |
1288 | else |
1289 | return -1; |
1290 | } |
1291 | |
1292 | static void print_section_list(const char * const list[20]) |
1293 | { |
1294 | const char *const *s = list; |
1295 | |
1296 | while (*s) { |
1297 | fprintf(stderr, "%s", *s); |
1298 | s++; |
1299 | if (*s) |
1300 | fprintf(stderr, ", "); |
1301 | } |
1302 | fprintf(stderr, "\n"); |
1303 | } |
1304 | |
1305 | /* |
1306 | * Print a warning about a section mismatch. |
1307 | * Try to find symbols near it so user can find it. |
1308 | * Check whitelist before warning - it may be a false positive. |
1309 | */ |
1310 | static void report_sec_mismatch(const char *modname, |
1311 | const struct sectioncheck *mismatch, |
1312 | const char *fromsec, |
1313 | unsigned long long fromaddr, |
1314 | const char *fromsym, |
1315 | int from_is_func, |
1316 | const char *tosec, const char *tosym, |
1317 | int to_is_func) |
1318 | { |
1319 | const char *from, *from_p; |
1320 | const char *to, *to_p; |
1321 | char *prl_from; |
1322 | char *prl_to; |
1323 | |
1324 | switch (from_is_func) { |
1325 | case 0: from = "variable"; from_p = ""; break; |
1326 | case 1: from = "function"; from_p = "()"; break; |
1327 | default: from = "(unknown reference)"; from_p = ""; break; |
1328 | } |
1329 | switch (to_is_func) { |
1330 | case 0: to = "variable"; to_p = ""; break; |
1331 | case 1: to = "function"; to_p = "()"; break; |
1332 | default: to = "(unknown reference)"; to_p = ""; break; |
1333 | } |
1334 | |
1335 | sec_mismatch_count++; |
1336 | if (!sec_mismatch_verbose) |
1337 | return; |
1338 | |
1339 | warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s " |
1340 | "to the %s %s:%s%s\n", |
1341 | modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec, |
1342 | tosym, to_p); |
1343 | |
1344 | switch (mismatch->mismatch) { |
1345 | case TEXT_TO_ANY_INIT: |
1346 | prl_from = sec2annotation(fromsec); |
1347 | prl_to = sec2annotation(tosec); |
1348 | fprintf(stderr, |
1349 | "The function %s%s() references\n" |
1350 | "the %s %s%s%s.\n" |
1351 | "This is often because %s lacks a %s\n" |
1352 | "annotation or the annotation of %s is wrong.\n", |
1353 | prl_from, fromsym, |
1354 | to, prl_to, tosym, to_p, |
1355 | fromsym, prl_to, tosym); |
1356 | free(prl_from); |
1357 | free(prl_to); |
1358 | break; |
1359 | case DATA_TO_ANY_INIT: { |
1360 | prl_to = sec2annotation(tosec); |
1361 | fprintf(stderr, |
1362 | "The variable %s references\n" |
1363 | "the %s %s%s%s\n" |
1364 | "If the reference is valid then annotate the\n" |
1365 | "variable with __init* or __refdata (see linux/init.h) " |
1366 | "or name the variable:\n", |
1367 | fromsym, to, prl_to, tosym, to_p); |
1368 | print_section_list(mismatch->symbol_white_list); |
1369 | free(prl_to); |
1370 | break; |
1371 | } |
1372 | case TEXT_TO_ANY_EXIT: |
1373 | prl_to = sec2annotation(tosec); |
1374 | fprintf(stderr, |
1375 | "The function %s() references a %s in an exit section.\n" |
1376 | "Often the %s %s%s has valid usage outside the exit section\n" |
1377 | "and the fix is to remove the %sannotation of %s.\n", |
1378 | fromsym, to, to, tosym, to_p, prl_to, tosym); |
1379 | free(prl_to); |
1380 | break; |
1381 | case DATA_TO_ANY_EXIT: { |
1382 | prl_to = sec2annotation(tosec); |
1383 | fprintf(stderr, |
1384 | "The variable %s references\n" |
1385 | "the %s %s%s%s\n" |
1386 | "If the reference is valid then annotate the\n" |
1387 | "variable with __exit* (see linux/init.h) or " |
1388 | "name the variable:\n", |
1389 | fromsym, to, prl_to, tosym, to_p); |
1390 | print_section_list(mismatch->symbol_white_list); |
1391 | free(prl_to); |
1392 | break; |
1393 | } |
1394 | case XXXINIT_TO_SOME_INIT: |
1395 | case XXXEXIT_TO_SOME_EXIT: |
1396 | prl_from = sec2annotation(fromsec); |
1397 | prl_to = sec2annotation(tosec); |
1398 | fprintf(stderr, |
1399 | "The %s %s%s%s references\n" |
1400 | "a %s %s%s%s.\n" |
1401 | "If %s is only used by %s then\n" |
1402 | "annotate %s with a matching annotation.\n", |
1403 | from, prl_from, fromsym, from_p, |
1404 | to, prl_to, tosym, to_p, |
1405 | tosym, fromsym, tosym); |
1406 | free(prl_from); |
1407 | free(prl_to); |
1408 | break; |
1409 | case ANY_INIT_TO_ANY_EXIT: |
1410 | prl_from = sec2annotation(fromsec); |
1411 | prl_to = sec2annotation(tosec); |
1412 | fprintf(stderr, |
1413 | "The %s %s%s%s references\n" |
1414 | "a %s %s%s%s.\n" |
1415 | "This is often seen when error handling " |
1416 | "in the init function\n" |
1417 | "uses functionality in the exit path.\n" |
1418 | "The fix is often to remove the %sannotation of\n" |
1419 | "%s%s so it may be used outside an exit section.\n", |
1420 | from, prl_from, fromsym, from_p, |
1421 | to, prl_to, tosym, to_p, |
1422 | prl_to, tosym, to_p); |
1423 | free(prl_from); |
1424 | free(prl_to); |
1425 | break; |
1426 | case ANY_EXIT_TO_ANY_INIT: |
1427 | prl_from = sec2annotation(fromsec); |
1428 | prl_to = sec2annotation(tosec); |
1429 | fprintf(stderr, |
1430 | "The %s %s%s%s references\n" |
1431 | "a %s %s%s%s.\n" |
1432 | "This is often seen when error handling " |
1433 | "in the exit function\n" |
1434 | "uses functionality in the init path.\n" |
1435 | "The fix is often to remove the %sannotation of\n" |
1436 | "%s%s so it may be used outside an init section.\n", |
1437 | from, prl_from, fromsym, from_p, |
1438 | to, prl_to, tosym, to_p, |
1439 | prl_to, tosym, to_p); |
1440 | free(prl_from); |
1441 | free(prl_to); |
1442 | break; |
1443 | case EXPORT_TO_INIT_EXIT: |
1444 | prl_to = sec2annotation(tosec); |
1445 | fprintf(stderr, |
1446 | "The symbol %s is exported and annotated %s\n" |
1447 | "Fix this by removing the %sannotation of %s " |
1448 | "or drop the export.\n", |
1449 | tosym, prl_to, prl_to, tosym); |
1450 | free(prl_to); |
1451 | break; |
1452 | } |
1453 | fprintf(stderr, "\n"); |
1454 | } |
1455 | |
1456 | static void check_section_mismatch(const char *modname, struct elf_info *elf, |
1457 | Elf_Rela *r, Elf_Sym *sym, const char *fromsec) |
1458 | { |
1459 | const char *tosec; |
1460 | const struct sectioncheck *mismatch; |
1461 | |
1462 | tosec = sec_name(elf, get_secindex(elf, sym)); |
1463 | mismatch = section_mismatch(fromsec, tosec); |
1464 | if (mismatch) { |
1465 | Elf_Sym *to; |
1466 | Elf_Sym *from; |
1467 | const char *tosym; |
1468 | const char *fromsym; |
1469 | |
1470 | from = find_elf_symbol2(elf, r->r_offset, fromsec); |
1471 | fromsym = sym_name(elf, from); |
1472 | to = find_elf_symbol(elf, r->r_addend, sym); |
1473 | tosym = sym_name(elf, to); |
1474 | |
1475 | /* check whitelist - we may ignore it */ |
1476 | if (secref_whitelist(mismatch, |
1477 | fromsec, fromsym, tosec, tosym)) { |
1478 | report_sec_mismatch(modname, mismatch, |
1479 | fromsec, r->r_offset, fromsym, |
1480 | is_function(from), tosec, tosym, |
1481 | is_function(to)); |
1482 | } |
1483 | } |
1484 | } |
1485 | |
1486 | static unsigned int *reloc_location(struct elf_info *elf, |
1487 | Elf_Shdr *sechdr, Elf_Rela *r) |
1488 | { |
1489 | Elf_Shdr *sechdrs = elf->sechdrs; |
1490 | int section = sechdr->sh_info; |
1491 | |
1492 | return (void *)elf->hdr + sechdrs[section].sh_offset + |
1493 | r->r_offset; |
1494 | } |
1495 | |
1496 | static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) |
1497 | { |
1498 | unsigned int r_typ = ELF_R_TYPE(r->r_info); |
1499 | unsigned int *location = reloc_location(elf, sechdr, r); |
1500 | |
1501 | switch (r_typ) { |
1502 | case R_386_32: |
1503 | r->r_addend = TO_NATIVE(*location); |
1504 | break; |
1505 | case R_386_PC32: |
1506 | r->r_addend = TO_NATIVE(*location) + 4; |
1507 | /* For CONFIG_RELOCATABLE=y */ |
1508 | if (elf->hdr->e_type == ET_EXEC) |
1509 | r->r_addend += r->r_offset; |
1510 | break; |
1511 | } |
1512 | return 0; |
1513 | } |
1514 | |
1515 | #ifndef R_ARM_CALL |
1516 | #define R_ARM_CALL 28 |
1517 | #endif |
1518 | #ifndef R_ARM_JUMP24 |
1519 | #define R_ARM_JUMP24 29 |
1520 | #endif |
1521 | |
1522 | static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) |
1523 | { |
1524 | unsigned int r_typ = ELF_R_TYPE(r->r_info); |
1525 | |
1526 | switch (r_typ) { |
1527 | case R_ARM_ABS32: |
1528 | /* From ARM ABI: (S + A) | T */ |
1529 | r->r_addend = (int)(long) |
1530 | (elf->symtab_start + ELF_R_SYM(r->r_info)); |
1531 | break; |
1532 | case R_ARM_PC24: |
1533 | case R_ARM_CALL: |
1534 | case R_ARM_JUMP24: |
1535 | /* From ARM ABI: ((S + A) | T) - P */ |
1536 | r->r_addend = (int)(long)(elf->hdr + |
1537 | sechdr->sh_offset + |
1538 | (r->r_offset - sechdr->sh_addr)); |
1539 | break; |
1540 | default: |
1541 | return 1; |
1542 | } |
1543 | return 0; |
1544 | } |
1545 | |
1546 | static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) |
1547 | { |
1548 | unsigned int r_typ = ELF_R_TYPE(r->r_info); |
1549 | unsigned int *location = reloc_location(elf, sechdr, r); |
1550 | unsigned int inst; |
1551 | |
1552 | if (r_typ == R_MIPS_HI16) |
1553 | return 1; /* skip this */ |
1554 | inst = TO_NATIVE(*location); |
1555 | switch (r_typ) { |
1556 | case R_MIPS_LO16: |
1557 | r->r_addend = inst & 0xffff; |
1558 | break; |
1559 | case R_MIPS_26: |
1560 | r->r_addend = (inst & 0x03ffffff) << 2; |
1561 | break; |
1562 | case R_MIPS_32: |
1563 | r->r_addend = inst; |
1564 | break; |
1565 | } |
1566 | return 0; |
1567 | } |
1568 | |
1569 | static void section_rela(const char *modname, struct elf_info *elf, |
1570 | Elf_Shdr *sechdr) |
1571 | { |
1572 | Elf_Sym *sym; |
1573 | Elf_Rela *rela; |
1574 | Elf_Rela r; |
1575 | unsigned int r_sym; |
1576 | const char *fromsec; |
1577 | |
1578 | Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset; |
1579 | Elf_Rela *stop = (void *)start + sechdr->sh_size; |
1580 | |
1581 | fromsec = sech_name(elf, sechdr); |
1582 | fromsec += strlen(".rela"); |
1583 | /* if from section (name) is know good then skip it */ |
1584 | if (match(fromsec, section_white_list)) |
1585 | return; |
1586 | |
1587 | for (rela = start; rela < stop; rela++) { |
1588 | r.r_offset = TO_NATIVE(rela->r_offset); |
1589 | #if KERNEL_ELFCLASS == ELFCLASS64 |
1590 | if (elf->hdr->e_machine == EM_MIPS) { |
1591 | unsigned int r_typ; |
1592 | r_sym = ELF64_MIPS_R_SYM(rela->r_info); |
1593 | r_sym = TO_NATIVE(r_sym); |
1594 | r_typ = ELF64_MIPS_R_TYPE(rela->r_info); |
1595 | r.r_info = ELF64_R_INFO(r_sym, r_typ); |
1596 | } else { |
1597 | r.r_info = TO_NATIVE(rela->r_info); |
1598 | r_sym = ELF_R_SYM(r.r_info); |
1599 | } |
1600 | #else |
1601 | r.r_info = TO_NATIVE(rela->r_info); |
1602 | r_sym = ELF_R_SYM(r.r_info); |
1603 | #endif |
1604 | r.r_addend = TO_NATIVE(rela->r_addend); |
1605 | sym = elf->symtab_start + r_sym; |
1606 | /* Skip special sections */ |
1607 | if (is_shndx_special(sym->st_shndx)) |
1608 | continue; |
1609 | check_section_mismatch(modname, elf, &r, sym, fromsec); |
1610 | } |
1611 | } |
1612 | |
1613 | static void section_rel(const char *modname, struct elf_info *elf, |
1614 | Elf_Shdr *sechdr) |
1615 | { |
1616 | Elf_Sym *sym; |
1617 | Elf_Rel *rel; |
1618 | Elf_Rela r; |
1619 | unsigned int r_sym; |
1620 | const char *fromsec; |
1621 | |
1622 | Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset; |
1623 | Elf_Rel *stop = (void *)start + sechdr->sh_size; |
1624 | |
1625 | fromsec = sech_name(elf, sechdr); |
1626 | fromsec += strlen(".rel"); |
1627 | /* if from section (name) is know good then skip it */ |
1628 | if (match(fromsec, section_white_list)) |
1629 | return; |
1630 | |
1631 | for (rel = start; rel < stop; rel++) { |
1632 | r.r_offset = TO_NATIVE(rel->r_offset); |
1633 | #if KERNEL_ELFCLASS == ELFCLASS64 |
1634 | if (elf->hdr->e_machine == EM_MIPS) { |
1635 | unsigned int r_typ; |
1636 | r_sym = ELF64_MIPS_R_SYM(rel->r_info); |
1637 | r_sym = TO_NATIVE(r_sym); |
1638 | r_typ = ELF64_MIPS_R_TYPE(rel->r_info); |
1639 | r.r_info = ELF64_R_INFO(r_sym, r_typ); |
1640 | } else { |
1641 | r.r_info = TO_NATIVE(rel->r_info); |
1642 | r_sym = ELF_R_SYM(r.r_info); |
1643 | } |
1644 | #else |
1645 | r.r_info = TO_NATIVE(rel->r_info); |
1646 | r_sym = ELF_R_SYM(r.r_info); |
1647 | #endif |
1648 | r.r_addend = 0; |
1649 | switch (elf->hdr->e_machine) { |
1650 | case EM_386: |
1651 | if (addend_386_rel(elf, sechdr, &r)) |
1652 | continue; |
1653 | break; |
1654 | case EM_ARM: |
1655 | if (addend_arm_rel(elf, sechdr, &r)) |
1656 | continue; |
1657 | break; |
1658 | case EM_MIPS: |
1659 | if (addend_mips_rel(elf, sechdr, &r)) |
1660 | continue; |
1661 | break; |
1662 | } |
1663 | sym = elf->symtab_start + r_sym; |
1664 | /* Skip special sections */ |
1665 | if (is_shndx_special(sym->st_shndx)) |
1666 | continue; |
1667 | check_section_mismatch(modname, elf, &r, sym, fromsec); |
1668 | } |
1669 | } |
1670 | |
1671 | /** |
1672 | * A module includes a number of sections that are discarded |
1673 | * either when loaded or when used as built-in. |
1674 | * For loaded modules all functions marked __init and all data |
1675 | * marked __initdata will be discarded when the module has been initialized. |
1676 | * Likewise for modules used built-in the sections marked __exit |
1677 | * are discarded because __exit marked function are supposed to be called |
1678 | * only when a module is unloaded which never happens for built-in modules. |
1679 | * The check_sec_ref() function traverses all relocation records |
1680 | * to find all references to a section that reference a section that will |
1681 | * be discarded and warns about it. |
1682 | **/ |
1683 | static void check_sec_ref(struct module *mod, const char *modname, |
1684 | struct elf_info *elf) |
1685 | { |
1686 | int i; |
1687 | Elf_Shdr *sechdrs = elf->sechdrs; |
1688 | |
1689 | /* Walk through all sections */ |
1690 | for (i = 0; i < elf->num_sections; i++) { |
1691 | check_section(modname, elf, &elf->sechdrs[i]); |
1692 | /* We want to process only relocation sections and not .init */ |
1693 | if (sechdrs[i].sh_type == SHT_RELA) |
1694 | section_rela(modname, elf, &elf->sechdrs[i]); |
1695 | else if (sechdrs[i].sh_type == SHT_REL) |
1696 | section_rel(modname, elf, &elf->sechdrs[i]); |
1697 | } |
1698 | } |
1699 | |
1700 | static void read_symbols(char *modname) |
1701 | { |
1702 | const char *symname; |
1703 | char *version; |
1704 | char *license; |
1705 | struct module *mod; |
1706 | struct elf_info info = { }; |
1707 | Elf_Sym *sym; |
1708 | |
1709 | if (!parse_elf(&info, modname)) |
1710 | return; |
1711 | |
1712 | mod = new_module(modname); |
1713 | |
1714 | /* When there's no vmlinux, don't print warnings about |
1715 | * unresolved symbols (since there'll be too many ;) */ |
1716 | if (is_vmlinux(modname)) { |
1717 | have_vmlinux = 1; |
1718 | mod->skip = 1; |
1719 | } |
1720 | |
1721 | license = get_modinfo(info.modinfo, info.modinfo_len, "license"); |
1722 | if (info.modinfo && !license && !is_vmlinux(modname)) |
1723 | warn("modpost: missing MODULE_LICENSE() in %s\n" |
1724 | "see include/linux/module.h for " |
1725 | "more information\n", modname); |
1726 | while (license) { |
1727 | if (license_is_gpl_compatible(license)) |
1728 | mod->gpl_compatible = 1; |
1729 | else { |
1730 | mod->gpl_compatible = 0; |
1731 | break; |
1732 | } |
1733 | license = get_next_modinfo(info.modinfo, info.modinfo_len, |
1734 | "license", license); |
1735 | } |
1736 | |
1737 | for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { |
1738 | symname = info.strtab + sym->st_name; |
1739 | |
1740 | handle_modversions(mod, &info, sym, symname); |
1741 | handle_moddevtable(mod, &info, sym, symname); |
1742 | } |
1743 | if (!is_vmlinux(modname) || |
1744 | (is_vmlinux(modname) && vmlinux_section_warnings)) |
1745 | check_sec_ref(mod, modname, &info); |
1746 | |
1747 | version = get_modinfo(info.modinfo, info.modinfo_len, "version"); |
1748 | if (version) |
1749 | maybe_frob_rcs_version(modname, version, info.modinfo, |
1750 | version - (char *)info.hdr); |
1751 | if (version || (all_versions && !is_vmlinux(modname))) |
1752 | get_src_version(modname, mod->srcversion, |
1753 | sizeof(mod->srcversion)-1); |
1754 | |
1755 | parse_elf_finish(&info); |
1756 | |
1757 | /* Our trick to get versioning for module struct etc. - it's |
1758 | * never passed as an argument to an exported function, so |
1759 | * the automatic versioning doesn't pick it up, but it's really |
1760 | * important anyhow */ |
1761 | if (modversions) |
1762 | mod->unres = alloc_symbol("module_layout", 0, mod->unres); |
1763 | } |
1764 | |
1765 | #define SZ 500 |
1766 | |
1767 | /* We first write the generated file into memory using the |
1768 | * following helper, then compare to the file on disk and |
1769 | * only update the later if anything changed */ |
1770 | |
1771 | void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf, |
1772 | const char *fmt, ...) |
1773 | { |
1774 | char tmp[SZ]; |
1775 | int len; |
1776 | va_list ap; |
1777 | |
1778 | va_start(ap, fmt); |
1779 | len = vsnprintf(tmp, SZ, fmt, ap); |
1780 | buf_write(buf, tmp, len); |
1781 | va_end(ap); |
1782 | } |
1783 | |
1784 | void buf_write(struct buffer *buf, const char *s, int len) |
1785 | { |
1786 | if (buf->size - buf->pos < len) { |
1787 | buf->size += len + SZ; |
1788 | buf->p = realloc(buf->p, buf->size); |
1789 | } |
1790 | strncpy(buf->p + buf->pos, s, len); |
1791 | buf->pos += len; |
1792 | } |
1793 | |
1794 | static void check_for_gpl_usage(enum export exp, const char *m, const char *s) |
1795 | { |
1796 | const char *e = is_vmlinux(m) ?"":".ko"; |
1797 | |
1798 | switch (exp) { |
1799 | case export_gpl: |
1800 | fatal("modpost: GPL-incompatible module %s%s " |
1801 | "uses GPL-only symbol '%s'\n", m, e, s); |
1802 | break; |
1803 | case export_unused_gpl: |
1804 | fatal("modpost: GPL-incompatible module %s%s " |
1805 | "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s); |
1806 | break; |
1807 | case export_gpl_future: |
1808 | warn("modpost: GPL-incompatible module %s%s " |
1809 | "uses future GPL-only symbol '%s'\n", m, e, s); |
1810 | break; |
1811 | case export_plain: |
1812 | case export_unused: |
1813 | case export_unknown: |
1814 | /* ignore */ |
1815 | break; |
1816 | } |
1817 | } |
1818 | |
1819 | static void check_for_unused(enum export exp, const char *m, const char *s) |
1820 | { |
1821 | const char *e = is_vmlinux(m) ?"":".ko"; |
1822 | |
1823 | switch (exp) { |
1824 | case export_unused: |
1825 | case export_unused_gpl: |
1826 | warn("modpost: module %s%s " |
1827 | "uses symbol '%s' marked UNUSED\n", m, e, s); |
1828 | break; |
1829 | default: |
1830 | /* ignore */ |
1831 | break; |
1832 | } |
1833 | } |
1834 | |
1835 | static void check_exports(struct module *mod) |
1836 | { |
1837 | struct symbol *s, *exp; |
1838 | |
1839 | for (s = mod->unres; s; s = s->next) { |
1840 | const char *basename; |
1841 | exp = find_symbol(s->name); |
1842 | if (!exp || exp->module == mod) |
1843 | continue; |
1844 | basename = strrchr(mod->name, '/'); |
1845 | if (basename) |
1846 | basename++; |
1847 | else |
1848 | basename = mod->name; |
1849 | if (!mod->gpl_compatible) |
1850 | check_for_gpl_usage(exp->export, basename, exp->name); |
1851 | check_for_unused(exp->export, basename, exp->name); |
1852 | } |
1853 | } |
1854 | |
1855 | /** |
1856 | * Header for the generated file |
1857 | **/ |
1858 | static void add_header(struct buffer *b, struct module *mod) |
1859 | { |
1860 | buf_printf(b, "#include <linux/module.h>\n"); |
1861 | buf_printf(b, "#include <linux/vermagic.h>\n"); |
1862 | buf_printf(b, "#include <linux/compiler.h>\n"); |
1863 | buf_printf(b, "\n"); |
1864 | buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n"); |
1865 | buf_printf(b, "\n"); |
1866 | buf_printf(b, "struct module __this_module\n"); |
1867 | buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n"); |
1868 | buf_printf(b, "\t.name = KBUILD_MODNAME,\n"); |
1869 | if (mod->has_init) |
1870 | buf_printf(b, "\t.init = init_module,\n"); |
1871 | if (mod->has_cleanup) |
1872 | buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n" |
1873 | "\t.exit = cleanup_module,\n" |
1874 | "#endif\n"); |
1875 | buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n"); |
1876 | buf_printf(b, "};\n"); |
1877 | } |
1878 | |
1879 | static void add_intree_flag(struct buffer *b, int is_intree) |
1880 | { |
1881 | if (is_intree) |
1882 | buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n"); |
1883 | } |
1884 | |
1885 | static void add_staging_flag(struct buffer *b, const char *name) |
1886 | { |
1887 | static const char *staging_dir = "drivers/staging"; |
1888 | |
1889 | if (strncmp(staging_dir, name, strlen(staging_dir)) == 0) |
1890 | buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); |
1891 | } |
1892 | |
1893 | /** |
1894 | * Record CRCs for unresolved symbols |
1895 | **/ |
1896 | static int add_versions(struct buffer *b, struct module *mod) |
1897 | { |
1898 | struct symbol *s, *exp; |
1899 | int err = 0; |
1900 | |
1901 | for (s = mod->unres; s; s = s->next) { |
1902 | exp = find_symbol(s->name); |
1903 | if (!exp || exp->module == mod) { |
1904 | if (have_vmlinux && !s->weak) { |
1905 | if (warn_unresolved) { |
1906 | warn("\"%s\" [%s.ko] undefined!\n", |
1907 | s->name, mod->name); |
1908 | } else { |
1909 | merror("\"%s\" [%s.ko] undefined!\n", |
1910 | s->name, mod->name); |
1911 | err = 1; |
1912 | } |
1913 | } |
1914 | continue; |
1915 | } |
1916 | s->module = exp->module; |
1917 | s->crc_valid = exp->crc_valid; |
1918 | s->crc = exp->crc; |
1919 | } |
1920 | |
1921 | if (!modversions) |
1922 | return err; |
1923 | |
1924 | buf_printf(b, "\n"); |
1925 | buf_printf(b, "static const struct modversion_info ____versions[]\n"); |
1926 | buf_printf(b, "__used\n"); |
1927 | buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n"); |
1928 | |
1929 | for (s = mod->unres; s; s = s->next) { |
1930 | if (!s->module) |
1931 | continue; |
1932 | if (!s->crc_valid) { |
1933 | warn("\"%s\" [%s.ko] has no CRC!\n", |
1934 | s->name, mod->name); |
1935 | continue; |
1936 | } |
1937 | buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name); |
1938 | } |
1939 | |
1940 | buf_printf(b, "};\n"); |
1941 | |
1942 | return err; |
1943 | } |
1944 | |
1945 | static void add_depends(struct buffer *b, struct module *mod, |
1946 | struct module *modules) |
1947 | { |
1948 | struct symbol *s; |
1949 | struct module *m; |
1950 | int first = 1; |
1951 | |
1952 | for (m = modules; m; m = m->next) |
1953 | m->seen = is_vmlinux(m->name); |
1954 | |
1955 | buf_printf(b, "\n"); |
1956 | buf_printf(b, "static const char __module_depends[]\n"); |
1957 | buf_printf(b, "__used\n"); |
1958 | buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n"); |
1959 | buf_printf(b, "\"depends="); |
1960 | for (s = mod->unres; s; s = s->next) { |
1961 | const char *p; |
1962 | if (!s->module) |
1963 | continue; |
1964 | |
1965 | if (s->module->seen) |
1966 | continue; |
1967 | |
1968 | s->module->seen = 1; |
1969 | p = strrchr(s->module->name, '/'); |
1970 | if (p) |
1971 | p++; |
1972 | else |
1973 | p = s->module->name; |
1974 | buf_printf(b, "%s%s", first ? "" : ",", p); |
1975 | first = 0; |
1976 | } |
1977 | buf_printf(b, "\";\n"); |
1978 | } |
1979 | |
1980 | static void add_srcversion(struct buffer *b, struct module *mod) |
1981 | { |
1982 | if (mod->srcversion[0]) { |
1983 | buf_printf(b, "\n"); |
1984 | buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n", |
1985 | mod->srcversion); |
1986 | } |
1987 | } |
1988 | |
1989 | static void write_if_changed(struct buffer *b, const char *fname) |
1990 | { |
1991 | char *tmp; |
1992 | FILE *file; |
1993 | struct stat st; |
1994 | |
1995 | file = fopen(fname, "r"); |
1996 | if (!file) |
1997 | goto write; |
1998 | |
1999 | if (fstat(fileno(file), &st) < 0) |
2000 | goto close_write; |
2001 | |
2002 | if (st.st_size != b->pos) |
2003 | goto close_write; |
2004 | |
2005 | tmp = NOFAIL(malloc(b->pos)); |
2006 | if (fread(tmp, 1, b->pos, file) != b->pos) |
2007 | goto free_write; |
2008 | |
2009 | if (memcmp(tmp, b->p, b->pos) != 0) |
2010 | goto free_write; |
2011 | |
2012 | free(tmp); |
2013 | fclose(file); |
2014 | return; |
2015 | |
2016 | free_write: |
2017 | free(tmp); |
2018 | close_write: |
2019 | fclose(file); |
2020 | write: |
2021 | file = fopen(fname, "w"); |
2022 | if (!file) { |
2023 | perror(fname); |
2024 | exit(1); |
2025 | } |
2026 | if (fwrite(b->p, 1, b->pos, file) != b->pos) { |
2027 | perror(fname); |
2028 | exit(1); |
2029 | } |
2030 | fclose(file); |
2031 | } |
2032 | |
2033 | /* parse Module.symvers file. line format: |
2034 | * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something] |
2035 | **/ |
2036 | static void read_dump(const char *fname, unsigned int kernel) |
2037 | { |
2038 | unsigned long size, pos = 0; |
2039 | void *file = grab_file(fname, &size); |
2040 | char *line; |
2041 | |
2042 | if (!file) |
2043 | /* No symbol versions, silently ignore */ |
2044 | return; |
2045 | |
2046 | while ((line = get_next_line(&pos, file, size))) { |
2047 | char *symname, *modname, *d, *export, *end; |
2048 | unsigned int crc; |
2049 | struct module *mod; |
2050 | struct symbol *s; |
2051 | |
2052 | if (!(symname = strchr(line, '\t'))) |
2053 | goto fail; |
2054 | *symname++ = '\0'; |
2055 | if (!(modname = strchr(symname, '\t'))) |
2056 | goto fail; |
2057 | *modname++ = '\0'; |
2058 | if ((export = strchr(modname, '\t')) != NULL) |
2059 | *export++ = '\0'; |
2060 | if (export && ((end = strchr(export, '\t')) != NULL)) |
2061 | *end = '\0'; |
2062 | crc = strtoul(line, &d, 16); |
2063 | if (*symname == '\0' || *modname == '\0' || *d != '\0') |
2064 | goto fail; |
2065 | mod = find_module(modname); |
2066 | if (!mod) { |
2067 | if (is_vmlinux(modname)) |
2068 | have_vmlinux = 1; |
2069 | mod = new_module(modname); |
2070 | mod->skip = 1; |
2071 | } |
2072 | s = sym_add_exported(symname, mod, export_no(export)); |
2073 | s->kernel = kernel; |
2074 | s->preloaded = 1; |
2075 | sym_update_crc(symname, mod, crc, export_no(export)); |
2076 | } |
2077 | return; |
2078 | fail: |
2079 | fatal("parse error in symbol dump file\n"); |
2080 | } |
2081 | |
2082 | /* For normal builds always dump all symbols. |
2083 | * For external modules only dump symbols |
2084 | * that are not read from kernel Module.symvers. |
2085 | **/ |
2086 | static int dump_sym(struct symbol *sym) |
2087 | { |
2088 | if (!external_module) |
2089 | return 1; |
2090 | if (sym->vmlinux || sym->kernel) |
2091 | return 0; |
2092 | return 1; |
2093 | } |
2094 | |
2095 | static void write_dump(const char *fname) |
2096 | { |
2097 | struct buffer buf = { }; |
2098 | struct symbol *symbol; |
2099 | int n; |
2100 | |
2101 | for (n = 0; n < SYMBOL_HASH_SIZE ; n++) { |
2102 | symbol = symbolhash[n]; |
2103 | while (symbol) { |
2104 | if (dump_sym(symbol)) |
2105 | buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n", |
2106 | symbol->crc, symbol->name, |
2107 | symbol->module->name, |
2108 | export_str(symbol->export)); |
2109 | symbol = symbol->next; |
2110 | } |
2111 | } |
2112 | write_if_changed(&buf, fname); |
2113 | } |
2114 | |
2115 | struct ext_sym_list { |
2116 | struct ext_sym_list *next; |
2117 | const char *file; |
2118 | }; |
2119 | |
2120 | int main(int argc, char **argv) |
2121 | { |
2122 | struct module *mod; |
2123 | struct buffer buf = { }; |
2124 | char *kernel_read = NULL, *module_read = NULL; |
2125 | char *dump_write = NULL; |
2126 | int opt; |
2127 | int err; |
2128 | struct ext_sym_list *extsym_iter; |
2129 | struct ext_sym_list *extsym_start = NULL; |
2130 | |
2131 | while ((opt = getopt(argc, argv, "i:I:e:msSo:awM:K:")) != -1) { |
2132 | switch (opt) { |
2133 | case 'i': |
2134 | kernel_read = optarg; |
2135 | break; |
2136 | case 'I': |
2137 | module_read = optarg; |
2138 | external_module = 1; |
2139 | break; |
2140 | case 'e': |
2141 | external_module = 1; |
2142 | extsym_iter = |
2143 | NOFAIL(malloc(sizeof(*extsym_iter))); |
2144 | extsym_iter->next = extsym_start; |
2145 | extsym_iter->file = optarg; |
2146 | extsym_start = extsym_iter; |
2147 | break; |
2148 | case 'm': |
2149 | modversions = 1; |
2150 | break; |
2151 | case 'o': |
2152 | dump_write = optarg; |
2153 | break; |
2154 | case 'a': |
2155 | all_versions = 1; |
2156 | break; |
2157 | case 's': |
2158 | vmlinux_section_warnings = 0; |
2159 | break; |
2160 | case 'S': |
2161 | sec_mismatch_verbose = 0; |
2162 | break; |
2163 | case 'w': |
2164 | warn_unresolved = 1; |
2165 | break; |
2166 | default: |
2167 | exit(1); |
2168 | } |
2169 | } |
2170 | |
2171 | if (kernel_read) |
2172 | read_dump(kernel_read, 1); |
2173 | if (module_read) |
2174 | read_dump(module_read, 0); |
2175 | while (extsym_start) { |
2176 | read_dump(extsym_start->file, 0); |
2177 | extsym_iter = extsym_start->next; |
2178 | free(extsym_start); |
2179 | extsym_start = extsym_iter; |
2180 | } |
2181 | |
2182 | while (optind < argc) |
2183 | read_symbols(argv[optind++]); |
2184 | |
2185 | for (mod = modules; mod; mod = mod->next) { |
2186 | if (mod->skip) |
2187 | continue; |
2188 | check_exports(mod); |
2189 | } |
2190 | |
2191 | err = 0; |
2192 | |
2193 | for (mod = modules; mod; mod = mod->next) { |
2194 | char fname[strlen(mod->name) + 10]; |
2195 | |
2196 | if (mod->skip) |
2197 | continue; |
2198 | |
2199 | buf.pos = 0; |
2200 | |
2201 | add_header(&buf, mod); |
2202 | add_intree_flag(&buf, !external_module); |
2203 | add_staging_flag(&buf, mod->name); |
2204 | err |= add_versions(&buf, mod); |
2205 | add_depends(&buf, mod, modules); |
2206 | add_moddevtable(&buf, mod); |
2207 | add_srcversion(&buf, mod); |
2208 | |
2209 | sprintf(fname, "%s.mod.c", mod->name); |
2210 | write_if_changed(&buf, fname); |
2211 | } |
2212 | |
2213 | if (dump_write) |
2214 | write_dump(dump_write); |
2215 | if (sec_mismatch_count && !sec_mismatch_verbose) |
2216 | warn("modpost: Found %d section mismatch(es).\n" |
2217 | "To see full details build your kernel with:\n" |
2218 | "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n", |
2219 | sec_mismatch_count); |
2220 | |
2221 | return err; |
2222 | } |
2223 |
Branches:
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ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
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jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9