blob: 3db4edcc5a12e7a923be9fb1c36ec644ebfff14f [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* Postprocess module symbol versions
2 *
3 * Copyright 2003 Kai Germaschewski
4 * Copyright 2002-2004 Rusty Russell, IBM Corporation
Sam Ravnborg382168f2006-02-26 20:11:17 +01005 * Copyright 2006 Sam Ravnborg
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 * 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"
Sam Ravnborgb817f6f2006-06-09 21:53:55 +020016#include "../../include/linux/license.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070017
18/* Are we using CONFIG_MODVERSIONS? */
19int modversions = 0;
20/* Warn about undefined symbols? (do so if we have vmlinux) */
21int have_vmlinux = 0;
22/* Is CONFIG_MODULE_SRCVERSION_ALL set? */
23static int all_versions = 0;
Sam Ravnborg040fcc82006-01-28 22:15:55 +010024/* If we are modposting external module set to 1 */
25static int external_module = 0;
Sam Ravnborg8d8d8282007-07-20 22:36:56 +020026/* Warn about section mismatch in vmlinux if set to 1 */
27static int vmlinux_section_warnings = 1;
Kirill Korotaevc53ddac2006-09-07 13:08:54 -070028/* Only warn about unresolved symbols */
29static int warn_unresolved = 0;
Ram Paibd5cbce2006-06-08 22:12:53 -070030/* How a symbol is exported */
Sam Ravnborgc96fca22006-07-01 11:44:23 +020031enum export {
32 export_plain, export_unused, export_gpl,
33 export_unused_gpl, export_gpl_future, export_unknown
34};
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
Sam Ravnborg5c3ead82006-01-28 17:19:35 +010036void fatal(const char *fmt, ...)
Linus Torvalds1da177e2005-04-16 15:20:36 -070037{
38 va_list arglist;
39
40 fprintf(stderr, "FATAL: ");
41
42 va_start(arglist, fmt);
43 vfprintf(stderr, fmt, arglist);
44 va_end(arglist);
45
46 exit(1);
47}
48
Sam Ravnborg5c3ead82006-01-28 17:19:35 +010049void warn(const char *fmt, ...)
Linus Torvalds1da177e2005-04-16 15:20:36 -070050{
51 va_list arglist;
52
53 fprintf(stderr, "WARNING: ");
54
55 va_start(arglist, fmt);
56 vfprintf(stderr, fmt, arglist);
57 va_end(arglist);
58}
59
Matthew Wilcox2a116652006-10-07 05:35:32 -060060void merror(const char *fmt, ...)
61{
62 va_list arglist;
63
64 fprintf(stderr, "ERROR: ");
65
66 va_start(arglist, fmt);
67 vfprintf(stderr, fmt, arglist);
68 va_end(arglist);
69}
70
Sam Ravnborg040fcc82006-01-28 22:15:55 +010071static int is_vmlinux(const char *modname)
72{
73 const char *myname;
74
75 if ((myname = strrchr(modname, '/')))
76 myname++;
77 else
78 myname = modname;
79
Sam Ravnborg741f98f2007-07-17 10:54:06 +020080 return (strcmp(myname, "vmlinux") == 0) ||
81 (strcmp(myname, "vmlinux.o") == 0);
Sam Ravnborg040fcc82006-01-28 22:15:55 +010082}
83
Linus Torvalds1da177e2005-04-16 15:20:36 -070084void *do_nofail(void *ptr, const char *expr)
85{
86 if (!ptr) {
87 fatal("modpost: Memory allocation failure: %s.\n", expr);
88 }
89 return ptr;
90}
91
92/* A list of all modules we processed */
93
94static struct module *modules;
95
Sam Ravnborg5c3ead82006-01-28 17:19:35 +010096static struct module *find_module(char *modname)
Linus Torvalds1da177e2005-04-16 15:20:36 -070097{
98 struct module *mod;
99
100 for (mod = modules; mod; mod = mod->next)
101 if (strcmp(mod->name, modname) == 0)
102 break;
103 return mod;
104}
105
Sam Ravnborg5c3ead82006-01-28 17:19:35 +0100106static struct module *new_module(char *modname)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107{
108 struct module *mod;
109 char *p, *s;
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100110
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 mod = NOFAIL(malloc(sizeof(*mod)));
112 memset(mod, 0, sizeof(*mod));
113 p = NOFAIL(strdup(modname));
114
115 /* strip trailing .o */
116 if ((s = strrchr(p, '.')) != NULL)
117 if (strcmp(s, ".o") == 0)
118 *s = '\0';
119
120 /* add to list */
121 mod->name = p;
Sam Ravnborgb817f6f2006-06-09 21:53:55 +0200122 mod->gpl_compatible = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123 mod->next = modules;
124 modules = mod;
125
126 return mod;
127}
128
129/* A hash of all exported symbols,
130 * struct symbol is also used for lists of unresolved symbols */
131
132#define SYMBOL_HASH_SIZE 1024
133
134struct symbol {
135 struct symbol *next;
136 struct module *module;
137 unsigned int crc;
138 int crc_valid;
139 unsigned int weak:1;
Sam Ravnborg040fcc82006-01-28 22:15:55 +0100140 unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */
141 unsigned int kernel:1; /* 1 if symbol is from kernel
142 * (only for external modules) **/
Sam Ravnborg8e70c452006-01-28 22:22:33 +0100143 unsigned int preloaded:1; /* 1 if symbol from Module.symvers */
Ram Paibd5cbce2006-06-08 22:12:53 -0700144 enum export export; /* Type of export */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145 char name[0];
146};
147
148static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
149
150/* This is based on the hash agorithm from gdbm, via tdb */
151static inline unsigned int tdb_hash(const char *name)
152{
153 unsigned value; /* Used to compute the hash value. */
154 unsigned i; /* Used to cycle through random values. */
155
156 /* Set the initial value from the key size. */
157 for (value = 0x238F13AF * strlen(name), i=0; name[i]; i++)
158 value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
159
160 return (1103515243 * value + 12345);
161}
162
Sam Ravnborg5c3ead82006-01-28 17:19:35 +0100163/**
164 * Allocate a new symbols for use in the hash of exported symbols or
165 * the list of unresolved symbols per module
166 **/
167static struct symbol *alloc_symbol(const char *name, unsigned int weak,
168 struct symbol *next)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169{
170 struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
171
172 memset(s, 0, sizeof(*s));
173 strcpy(s->name, name);
174 s->weak = weak;
175 s->next = next;
176 return s;
177}
178
179/* For the hash of exported symbols */
Ram Paibd5cbce2006-06-08 22:12:53 -0700180static struct symbol *new_symbol(const char *name, struct module *module,
181 enum export export)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182{
183 unsigned int hash;
184 struct symbol *new;
185
186 hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
187 new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
188 new->module = module;
Ram Paibd5cbce2006-06-08 22:12:53 -0700189 new->export = export;
Sam Ravnborg040fcc82006-01-28 22:15:55 +0100190 return new;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191}
192
Sam Ravnborg5c3ead82006-01-28 17:19:35 +0100193static struct symbol *find_symbol(const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194{
195 struct symbol *s;
196
197 /* For our purposes, .foo matches foo. PPC64 needs this. */
198 if (name[0] == '.')
199 name++;
200
201 for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s=s->next) {
202 if (strcmp(s->name, name) == 0)
203 return s;
204 }
205 return NULL;
206}
207
Ram Paibd5cbce2006-06-08 22:12:53 -0700208static struct {
209 const char *str;
210 enum export export;
211} export_list[] = {
212 { .str = "EXPORT_SYMBOL", .export = export_plain },
Sam Ravnborgc96fca22006-07-01 11:44:23 +0200213 { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
Ram Paibd5cbce2006-06-08 22:12:53 -0700214 { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
Sam Ravnborgc96fca22006-07-01 11:44:23 +0200215 { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
Ram Paibd5cbce2006-06-08 22:12:53 -0700216 { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
217 { .str = "(unknown)", .export = export_unknown },
218};
219
220
221static const char *export_str(enum export ex)
222{
223 return export_list[ex].str;
224}
225
226static enum export export_no(const char * s)
227{
228 int i;
Sam Ravnborg534b89a2006-07-01 10:10:19 +0200229 if (!s)
230 return export_unknown;
Ram Paibd5cbce2006-06-08 22:12:53 -0700231 for (i = 0; export_list[i].export != export_unknown; i++) {
232 if (strcmp(export_list[i].str, s) == 0)
233 return export_list[i].export;
234 }
235 return export_unknown;
236}
237
238static enum export export_from_sec(struct elf_info *elf, Elf_Section sec)
239{
240 if (sec == elf->export_sec)
241 return export_plain;
Sam Ravnborgc96fca22006-07-01 11:44:23 +0200242 else if (sec == elf->export_unused_sec)
243 return export_unused;
Ram Paibd5cbce2006-06-08 22:12:53 -0700244 else if (sec == elf->export_gpl_sec)
245 return export_gpl;
Sam Ravnborgc96fca22006-07-01 11:44:23 +0200246 else if (sec == elf->export_unused_gpl_sec)
247 return export_unused_gpl;
Ram Paibd5cbce2006-06-08 22:12:53 -0700248 else if (sec == elf->export_gpl_future_sec)
249 return export_gpl_future;
250 else
251 return export_unknown;
252}
253
Sam Ravnborg5c3ead82006-01-28 17:19:35 +0100254/**
255 * Add an exported symbol - it may have already been added without a
256 * CRC, in this case just update the CRC
257 **/
Ram Paibd5cbce2006-06-08 22:12:53 -0700258static struct symbol *sym_add_exported(const char *name, struct module *mod,
259 enum export export)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260{
261 struct symbol *s = find_symbol(name);
262
263 if (!s) {
Ram Paibd5cbce2006-06-08 22:12:53 -0700264 s = new_symbol(name, mod, export);
Sam Ravnborg8e70c452006-01-28 22:22:33 +0100265 } else {
266 if (!s->preloaded) {
Sam Ravnborg7b75b132006-03-05 13:48:58 +0100267 warn("%s: '%s' exported twice. Previous export "
Sam Ravnborg8e70c452006-01-28 22:22:33 +0100268 "was in %s%s\n", mod->name, name,
269 s->module->name,
270 is_vmlinux(s->module->name) ?"":".ko");
271 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 }
Sam Ravnborg8e70c452006-01-28 22:22:33 +0100273 s->preloaded = 0;
Sam Ravnborg040fcc82006-01-28 22:15:55 +0100274 s->vmlinux = is_vmlinux(mod->name);
275 s->kernel = 0;
Ram Paibd5cbce2006-06-08 22:12:53 -0700276 s->export = export;
Sam Ravnborg040fcc82006-01-28 22:15:55 +0100277 return s;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278}
279
Sam Ravnborg040fcc82006-01-28 22:15:55 +0100280static void sym_update_crc(const char *name, struct module *mod,
Ram Paibd5cbce2006-06-08 22:12:53 -0700281 unsigned int crc, enum export export)
Sam Ravnborg040fcc82006-01-28 22:15:55 +0100282{
283 struct symbol *s = find_symbol(name);
284
285 if (!s)
Ram Paibd5cbce2006-06-08 22:12:53 -0700286 s = new_symbol(name, mod, export);
Sam Ravnborg040fcc82006-01-28 22:15:55 +0100287 s->crc = crc;
288 s->crc_valid = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289}
290
Sam Ravnborg5c3ead82006-01-28 17:19:35 +0100291void *grab_file(const char *filename, unsigned long *size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292{
293 struct stat st;
294 void *map;
295 int fd;
296
297 fd = open(filename, O_RDONLY);
298 if (fd < 0 || fstat(fd, &st) != 0)
299 return NULL;
300
301 *size = st.st_size;
302 map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
303 close(fd);
304
305 if (map == MAP_FAILED)
306 return NULL;
307 return map;
308}
309
Sam Ravnborg5c3ead82006-01-28 17:19:35 +0100310/**
311 * Return a copy of the next line in a mmap'ed file.
312 * spaces in the beginning of the line is trimmed away.
313 * Return a pointer to a static buffer.
314 **/
315char* get_next_line(unsigned long *pos, void *file, unsigned long size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316{
317 static char line[4096];
318 int skip = 1;
319 size_t len = 0;
320 signed char *p = (signed char *)file + *pos;
321 char *s = line;
322
323 for (; *pos < size ; (*pos)++)
324 {
325 if (skip && isspace(*p)) {
326 p++;
327 continue;
328 }
329 skip = 0;
330 if (*p != '\n' && (*pos < size)) {
331 len++;
332 *s++ = *p++;
333 if (len > 4095)
334 break; /* Too long, stop */
335 } else {
336 /* End of string */
337 *s = '\0';
338 return line;
339 }
340 }
341 /* End of buffer */
342 return NULL;
343}
344
Sam Ravnborg5c3ead82006-01-28 17:19:35 +0100345void release_file(void *file, unsigned long size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346{
347 munmap(file, size);
348}
349
Sam Ravnborg85bd2fd2007-02-26 15:33:52 +0100350static int parse_elf(struct elf_info *info, const char *filename)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351{
352 unsigned int i;
Sam Ravnborg85bd2fd2007-02-26 15:33:52 +0100353 Elf_Ehdr *hdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 Elf_Shdr *sechdrs;
355 Elf_Sym *sym;
356
357 hdr = grab_file(filename, &info->size);
358 if (!hdr) {
359 perror(filename);
Sam Ravnborg6803dc02006-06-24 23:46:54 +0200360 exit(1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 }
362 info->hdr = hdr;
Sam Ravnborg85bd2fd2007-02-26 15:33:52 +0100363 if (info->size < sizeof(*hdr)) {
364 /* file too small, assume this is an empty .o file */
365 return 0;
366 }
367 /* Is this a valid ELF file? */
368 if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
369 (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
370 (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
371 (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
372 /* Not an ELF file - silently ignore it */
373 return 0;
374 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375 /* Fix endianness in ELF header */
376 hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
377 hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
378 hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
379 hdr->e_machine = TO_NATIVE(hdr->e_machine);
Atsushi Nemotoae4ac122007-05-22 18:27:39 +0900380 hdr->e_type = TO_NATIVE(hdr->e_type);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381 sechdrs = (void *)hdr + hdr->e_shoff;
382 info->sechdrs = sechdrs;
383
384 /* Fix endianness in section headers */
385 for (i = 0; i < hdr->e_shnum; i++) {
386 sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
387 sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
388 sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
389 sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
390 sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
Atsushi Nemotoae4ac122007-05-22 18:27:39 +0900391 sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
392 sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 }
394 /* Find symbol table. */
395 for (i = 1; i < hdr->e_shnum; i++) {
396 const char *secstrings
397 = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
Ram Paibd5cbce2006-06-08 22:12:53 -0700398 const char *secname;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399
Sam Ravnborg85bd2fd2007-02-26 15:33:52 +0100400 if (sechdrs[i].sh_offset > info->size) {
401 fatal("%s is truncated. sechdrs[i].sh_offset=%u > sizeof(*hrd)=%ul\n", filename, (unsigned int)sechdrs[i].sh_offset, sizeof(*hdr));
402 return 0;
403 }
Ram Paibd5cbce2006-06-08 22:12:53 -0700404 secname = secstrings + sechdrs[i].sh_name;
405 if (strcmp(secname, ".modinfo") == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406 info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
407 info->modinfo_len = sechdrs[i].sh_size;
Ram Paibd5cbce2006-06-08 22:12:53 -0700408 } else if (strcmp(secname, "__ksymtab") == 0)
409 info->export_sec = i;
Sam Ravnborgc96fca22006-07-01 11:44:23 +0200410 else if (strcmp(secname, "__ksymtab_unused") == 0)
411 info->export_unused_sec = i;
Ram Paibd5cbce2006-06-08 22:12:53 -0700412 else if (strcmp(secname, "__ksymtab_gpl") == 0)
413 info->export_gpl_sec = i;
Sam Ravnborgc96fca22006-07-01 11:44:23 +0200414 else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
415 info->export_unused_gpl_sec = i;
Ram Paibd5cbce2006-06-08 22:12:53 -0700416 else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
417 info->export_gpl_future_sec = i;
418
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 if (sechdrs[i].sh_type != SHT_SYMTAB)
420 continue;
421
422 info->symtab_start = (void *)hdr + sechdrs[i].sh_offset;
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100423 info->symtab_stop = (void *)hdr + sechdrs[i].sh_offset
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 + sechdrs[i].sh_size;
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100425 info->strtab = (void *)hdr +
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 sechdrs[sechdrs[i].sh_link].sh_offset;
427 }
428 if (!info->symtab_start) {
Sam Ravnborgcb805142006-01-28 16:57:26 +0100429 fatal("%s has no symtab?\n", filename);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430 }
431 /* Fix endianness in symbols */
432 for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
433 sym->st_shndx = TO_NATIVE(sym->st_shndx);
434 sym->st_name = TO_NATIVE(sym->st_name);
435 sym->st_value = TO_NATIVE(sym->st_value);
436 sym->st_size = TO_NATIVE(sym->st_size);
437 }
Sam Ravnborg85bd2fd2007-02-26 15:33:52 +0100438 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439}
440
Sam Ravnborg5c3ead82006-01-28 17:19:35 +0100441static void parse_elf_finish(struct elf_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442{
443 release_file(info->hdr, info->size);
444}
445
Luke Yangf7b05e62006-03-02 18:35:31 +0800446#define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_"
447#define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448
Sam Ravnborg5c3ead82006-01-28 17:19:35 +0100449static void handle_modversions(struct module *mod, struct elf_info *info,
450 Elf_Sym *sym, const char *symname)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451{
452 unsigned int crc;
Ram Paibd5cbce2006-06-08 22:12:53 -0700453 enum export export = export_from_sec(info, sym->st_shndx);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454
455 switch (sym->st_shndx) {
456 case SHN_COMMON:
Sam Ravnborgcb805142006-01-28 16:57:26 +0100457 warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 break;
459 case SHN_ABS:
460 /* CRC'd symbol */
461 if (memcmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
462 crc = (unsigned int) sym->st_value;
Ram Paibd5cbce2006-06-08 22:12:53 -0700463 sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
464 export);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 }
466 break;
467 case SHN_UNDEF:
468 /* undefined symbol */
469 if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
470 ELF_ST_BIND(sym->st_info) != STB_WEAK)
471 break;
472 /* ignore global offset table */
473 if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
474 break;
475 /* ignore __this_module, it will be resolved shortly */
476 if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0)
477 break;
Ben Colline8d529012005-08-19 13:44:57 -0700478/* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
479#if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
480/* add compatibility with older glibc */
481#ifndef STT_SPARC_REGISTER
482#define STT_SPARC_REGISTER STT_REGISTER
483#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484 if (info->hdr->e_machine == EM_SPARC ||
485 info->hdr->e_machine == EM_SPARCV9) {
486 /* Ignore register directives. */
Ben Colline8d529012005-08-19 13:44:57 -0700487 if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488 break;
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100489 if (symname[0] == '.') {
490 char *munged = strdup(symname);
491 munged[0] = '_';
492 munged[1] = toupper(munged[1]);
493 symname = munged;
494 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 }
496#endif
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100497
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 if (memcmp(symname, MODULE_SYMBOL_PREFIX,
499 strlen(MODULE_SYMBOL_PREFIX)) == 0)
500 mod->unres = alloc_symbol(symname +
501 strlen(MODULE_SYMBOL_PREFIX),
502 ELF_ST_BIND(sym->st_info) == STB_WEAK,
503 mod->unres);
504 break;
505 default:
506 /* All exported symbols */
507 if (memcmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
Ram Paibd5cbce2006-06-08 22:12:53 -0700508 sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
509 export);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510 }
511 if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
512 mod->has_init = 1;
513 if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0)
514 mod->has_cleanup = 1;
515 break;
516 }
517}
518
Sam Ravnborg5c3ead82006-01-28 17:19:35 +0100519/**
520 * Parse tag=value strings from .modinfo section
521 **/
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522static char *next_string(char *string, unsigned long *secsize)
523{
524 /* Skip non-zero chars */
525 while (string[0]) {
526 string++;
527 if ((*secsize)-- <= 1)
528 return NULL;
529 }
530
531 /* Skip any zero padding. */
532 while (!string[0]) {
533 string++;
534 if ((*secsize)-- <= 1)
535 return NULL;
536 }
537 return string;
538}
539
Sam Ravnborgb817f6f2006-06-09 21:53:55 +0200540static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
541 const char *tag, char *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542{
543 char *p;
544 unsigned int taglen = strlen(tag);
545 unsigned long size = modinfo_len;
546
Sam Ravnborgb817f6f2006-06-09 21:53:55 +0200547 if (info) {
548 size -= info - (char *)modinfo;
549 modinfo = next_string(info, &size);
550 }
551
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 for (p = modinfo; p; p = next_string(p, &size)) {
553 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
554 return p + taglen + 1;
555 }
556 return NULL;
557}
558
Sam Ravnborgb817f6f2006-06-09 21:53:55 +0200559static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
560 const char *tag)
561
562{
563 return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
564}
565
Sam Ravnborg93684d32006-02-19 11:53:35 +0100566/**
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100567 * Test if string s ends in string sub
568 * return 0 if match
569 **/
570static int strrcmp(const char *s, const char *sub)
571{
572 int slen, sublen;
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100573
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100574 if (!s || !sub)
575 return 1;
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100576
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100577 slen = strlen(s);
578 sublen = strlen(sub);
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100579
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100580 if ((slen == 0) || (sublen == 0))
581 return 1;
582
583 if (sublen > slen)
584 return 1;
585
586 return memcmp(s + slen - sublen, sub, sublen);
587}
588
Sam Ravnborg2f5ee612007-07-25 21:46:40 +0200589/*
590 * Functions used only during module init is marked __init and is stored in
591 * a .init.text section. Likewise data is marked __initdata and stored in
592 * a .init.data section.
593 * If this section is one of these sections return 1
594 * See include/linux/init.h for the details
595 */
596static int init_section(const char *name)
597{
598 if (strcmp(name, ".init") == 0)
599 return 1;
600 if (strncmp(name, ".init.", strlen(".init.")) == 0)
601 return 1;
602 return 0;
603}
604
605/*
606 * Functions used only during module exit is marked __exit and is stored in
607 * a .exit.text section. Likewise data is marked __exitdata and stored in
608 * a .exit.data section.
609 * If this section is one of these sections return 1
610 * See include/linux/init.h for the details
611 **/
612static int exit_section(const char *name)
613{
614 if (strcmp(name, ".exit.text") == 0)
615 return 1;
616 if (strcmp(name, ".exit.data") == 0)
617 return 1;
618 return 0;
619
620}
621
622/*
623 * Data sections are named like this:
624 * .data | .data.rel | .data.rel.*
625 * Return 1 if the specified section is a data section
626 */
627static int data_section(const char *name)
628{
629 if ((strcmp(name, ".data") == 0) ||
630 (strcmp(name, ".data.rel") == 0) ||
631 (strncmp(name, ".data.rel.", strlen(".data.rel.")) == 0))
632 return 1;
633 else
634 return 0;
635}
636
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100637/**
638 * Whitelist to allow certain references to pass with no warning.
Sam Ravnborg0e0d3142007-05-17 20:14:48 +0200639 *
640 * Pattern 0:
641 * Do not warn if funtion/data are marked with __init_refok/__initdata_refok.
642 * The pattern is identified by:
643 * fromsec = .text.init.refok | .data.init.refok
644 *
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100645 * Pattern 1:
646 * If a module parameter is declared __initdata and permissions=0
647 * then this is legal despite the warning generated.
648 * We cannot see value of permissions here, so just ignore
649 * this pattern.
650 * The pattern is identified by:
651 * tosec = .init.data
Sam Ravnborg9209aed2006-03-05 00:16:26 +0100652 * fromsec = .data*
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100653 * atsym =__param*
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100654 *
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100655 * Pattern 2:
Randy Dunlap72ee59b2006-04-15 11:17:12 -0700656 * Many drivers utilise a *driver container with references to
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100657 * add, remove, probe functions etc.
658 * These functions may often be marked __init and we do not want to
659 * warn here.
660 * the pattern is identified by:
Sam Ravnborg83cda2b2007-07-25 21:52:31 +0200661 * tosec = init or exit section
662 * fromsec = data section
Sam Ravnborg1e29a702007-06-03 22:19:24 +0200663 * atsym = *driver, *_template, *_sht, *_ops, *_probe, *probe_one, *_console, *_timer
Vivek Goyalee6a8542007-01-11 01:52:44 +0100664 *
665 * Pattern 3:
Sam Ravnborg9bf8cb92007-02-26 17:49:06 +0100666 * Whitelist all refereces from .text.head to .init.data
667 * Whitelist all refereces from .text.head to .init.text
668 *
Sam Ravnborg1d8af552007-06-03 00:41:22 +0200669 * Pattern 4:
Vivek Goyalee6a8542007-01-11 01:52:44 +0100670 * Some symbols belong to init section but still it is ok to reference
671 * these from non-init sections as these symbols don't have any memory
672 * allocated for them and symbol address and value are same. So even
673 * if init section is freed, its ok to reference those symbols.
674 * For ex. symbols marking the init section boundaries.
675 * This pattern is identified by
676 * refsymname = __init_begin, _sinittext, _einittext
Sam Ravnborg9bf8cb92007-02-26 17:49:06 +0100677 *
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100678 **/
Magnus Damm9e157a52006-08-08 17:32:11 +0900679static int secref_whitelist(const char *modname, const char *tosec,
Vivek Goyalee6a8542007-01-11 01:52:44 +0100680 const char *fromsec, const char *atsym,
681 const char *refsymname)
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100682{
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100683 const char **s;
684 const char *pat2sym[] = {
Randy Dunlap72ee59b2006-04-15 11:17:12 -0700685 "driver",
Sam Ravnborg5ecdd0f2006-04-14 23:54:13 +0200686 "_template", /* scsi uses *_template a lot */
Sam Ravnborg1e29a702007-06-03 22:19:24 +0200687 "_timer", /* arm uses ops structures named _timer a lot */
Sam Ravnborg5ecdd0f2006-04-14 23:54:13 +0200688 "_sht", /* scsi also used *_sht to some extent */
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100689 "_ops",
690 "_probe",
691 "_probe_one",
Vivek Goyal118c0ac2007-01-11 01:52:44 +0100692 "_console",
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100693 NULL
694 };
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100695
Vivek Goyalee6a8542007-01-11 01:52:44 +0100696 const char *pat3refsym[] = {
697 "__init_begin",
698 "_sinittext",
699 "_einittext",
700 NULL
701 };
702
Sam Ravnborg0e0d3142007-05-17 20:14:48 +0200703 /* Check for pattern 0 */
704 if ((strcmp(fromsec, ".text.init.refok") == 0) ||
705 (strcmp(fromsec, ".data.init.refok") == 0))
706 return 1;
707
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100708 /* Check for pattern 1 */
Sam Ravnborg83cda2b2007-07-25 21:52:31 +0200709 if ((strcmp(tosec, ".init.data") == 0) &&
710 (strncmp(fromsec, ".data", strlen(".data")) == 0) &&
711 (strncmp(atsym, "__param", strlen("__param")) == 0))
712 return 1;
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100713
714 /* Check for pattern 2 */
Sam Ravnborg83cda2b2007-07-25 21:52:31 +0200715 if ((init_section(tosec) || exit_section(tosec)) && data_section(fromsec))
716 for (s = pat2sym; *s; s++)
717 if (strrcmp(atsym, *s) == 0)
718 return 1;
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100719
Sam Ravnborg9bf8cb92007-02-26 17:49:06 +0100720 /* Check for pattern 3 */
Sam Ravnborg9bf8cb92007-02-26 17:49:06 +0100721 if ((strcmp(fromsec, ".text.head") == 0) &&
722 ((strcmp(tosec, ".init.data") == 0) ||
723 (strcmp(tosec, ".init.text") == 0)))
724 return 1;
725
Sam Ravnborg1d8af552007-06-03 00:41:22 +0200726 /* Check for pattern 4 */
Sam Ravnborg9bf8cb92007-02-26 17:49:06 +0100727 for (s = pat3refsym; *s; s++)
728 if (strcmp(refsymname, *s) == 0)
729 return 1;
730
Sam Ravnborg93659af2006-08-09 08:23:55 +0200731 return 0;
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100732}
733
734/**
Sam Ravnborg93684d32006-02-19 11:53:35 +0100735 * Find symbol based on relocation record info.
736 * In some cases the symbol supplied is a valid symbol so
737 * return refsym. If st_name != 0 we assume this is a valid symbol.
738 * In other cases the symbol needs to be looked up in the symbol table
739 * based on section and address.
740 * **/
741static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf_Addr addr,
742 Elf_Sym *relsym)
743{
744 Elf_Sym *sym;
745
746 if (relsym->st_name != 0)
747 return relsym;
748 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
749 if (sym->st_shndx != relsym->st_shndx)
750 continue;
Atsushi Nemotoae4ac122007-05-22 18:27:39 +0900751 if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
752 continue;
Sam Ravnborg93684d32006-02-19 11:53:35 +0100753 if (sym->st_value == addr)
754 return sym;
755 }
756 return NULL;
757}
758
David Brownellda68d612007-02-20 13:58:16 -0800759static inline int is_arm_mapping_symbol(const char *str)
760{
761 return str[0] == '$' && strchr("atd", str[1])
762 && (str[2] == '\0' || str[2] == '.');
763}
764
765/*
766 * If there's no name there, ignore it; likewise, ignore it if it's
767 * one of the magic symbols emitted used by current ARM tools.
768 *
769 * Otherwise if find_symbols_between() returns those symbols, they'll
770 * fail the whitelist tests and cause lots of false alarms ... fixable
771 * only by merging __exit and __init sections into __text, bloating
772 * the kernel (which is especially evil on embedded platforms).
773 */
774static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
775{
776 const char *name = elf->strtab + sym->st_name;
777
778 if (!name || !strlen(name))
779 return 0;
780 return !is_arm_mapping_symbol(name);
781}
782
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100783/*
Sam Ravnborg43c74d12006-03-05 12:02:46 +0100784 * Find symbols before or equal addr and after addr - in the section sec.
785 * If we find two symbols with equal offset prefer one with a valid name.
786 * The ELF format may have a better way to detect what type of symbol
787 * it is, but this works for now.
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100788 **/
789static void find_symbols_between(struct elf_info *elf, Elf_Addr addr,
790 const char *sec,
791 Elf_Sym **before, Elf_Sym **after)
792{
793 Elf_Sym *sym;
794 Elf_Ehdr *hdr = elf->hdr;
795 Elf_Addr beforediff = ~0;
796 Elf_Addr afterdiff = ~0;
797 const char *secstrings = (void *)hdr +
798 elf->sechdrs[hdr->e_shstrndx].sh_offset;
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100799
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100800 *before = NULL;
801 *after = NULL;
802
803 for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
804 const char *symsec;
805
806 if (sym->st_shndx >= SHN_LORESERVE)
807 continue;
808 symsec = secstrings + elf->sechdrs[sym->st_shndx].sh_name;
809 if (strcmp(symsec, sec) != 0)
810 continue;
David Brownellda68d612007-02-20 13:58:16 -0800811 if (!is_valid_name(elf, sym))
812 continue;
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100813 if (sym->st_value <= addr) {
814 if ((addr - sym->st_value) < beforediff) {
815 beforediff = addr - sym->st_value;
816 *before = sym;
817 }
Sam Ravnborg43c74d12006-03-05 12:02:46 +0100818 else if ((addr - sym->st_value) == beforediff) {
David Brownellda68d612007-02-20 13:58:16 -0800819 *before = sym;
Sam Ravnborg43c74d12006-03-05 12:02:46 +0100820 }
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100821 }
822 else
823 {
824 if ((sym->st_value - addr) < afterdiff) {
825 afterdiff = sym->st_value - addr;
826 *after = sym;
827 }
Sam Ravnborg43c74d12006-03-05 12:02:46 +0100828 else if ((sym->st_value - addr) == afterdiff) {
David Brownellda68d612007-02-20 13:58:16 -0800829 *after = sym;
Sam Ravnborg43c74d12006-03-05 12:02:46 +0100830 }
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100831 }
832 }
833}
834
835/**
836 * Print a warning about a section mismatch.
837 * Try to find symbols near it so user can find it.
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100838 * Check whitelist before warning - it may be a false positive.
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100839 **/
840static void warn_sec_mismatch(const char *modname, const char *fromsec,
841 struct elf_info *elf, Elf_Sym *sym, Elf_Rela r)
842{
Sam Ravnborg93684d32006-02-19 11:53:35 +0100843 const char *refsymname = "";
844 Elf_Sym *before, *after;
845 Elf_Sym *refsym;
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100846 Elf_Ehdr *hdr = elf->hdr;
847 Elf_Shdr *sechdrs = elf->sechdrs;
848 const char *secstrings = (void *)hdr +
849 sechdrs[hdr->e_shstrndx].sh_offset;
850 const char *secname = secstrings + sechdrs[sym->st_shndx].sh_name;
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100851
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100852 find_symbols_between(elf, r.r_offset, fromsec, &before, &after);
853
Sam Ravnborg93684d32006-02-19 11:53:35 +0100854 refsym = find_elf_symbol(elf, r.r_addend, sym);
855 if (refsym && strlen(elf->strtab + refsym->st_name))
856 refsymname = elf->strtab + refsym->st_name;
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100857
858 /* check whitelist - we may ignore it */
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100859 if (before &&
Magnus Damm9e157a52006-08-08 17:32:11 +0900860 secref_whitelist(modname, secname, fromsec,
Vivek Goyalee6a8542007-01-11 01:52:44 +0100861 elf->strtab + before->st_name, refsymname))
Sam Ravnborg4c8fbca2006-02-26 22:18:11 +0100862 return;
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100863
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100864 if (before && after) {
Russell King256012092007-05-10 23:03:25 +0100865 warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
866 "(between '%s' and '%s')\n",
867 modname, fromsec, (unsigned long long)r.r_offset,
868 secname, refsymname,
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100869 elf->strtab + before->st_name,
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100870 elf->strtab + after->st_name);
871 } else if (before) {
Russell King256012092007-05-10 23:03:25 +0100872 warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
873 "(after '%s')\n",
874 modname, fromsec, (unsigned long long)r.r_offset,
875 secname, refsymname,
876 elf->strtab + before->st_name);
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100877 } else if (after) {
Russell King256012092007-05-10 23:03:25 +0100878 warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
Sam Ravnborg93684d32006-02-19 11:53:35 +0100879 "before '%s' (at offset -0x%llx)\n",
Russell King256012092007-05-10 23:03:25 +0100880 modname, fromsec, (unsigned long long)r.r_offset,
881 secname, refsymname,
882 elf->strtab + after->st_name);
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100883 } else {
Russell King256012092007-05-10 23:03:25 +0100884 warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s\n",
885 modname, fromsec, (unsigned long long)r.r_offset,
886 secname, refsymname);
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100887 }
888}
889
Atsushi Nemotoae4ac122007-05-22 18:27:39 +0900890static unsigned int *reloc_location(struct elf_info *elf,
891 int rsection, Elf_Rela *r)
892{
893 Elf_Shdr *sechdrs = elf->sechdrs;
894 int section = sechdrs[rsection].sh_info;
895
896 return (void *)elf->hdr + sechdrs[section].sh_offset +
897 (r->r_offset - sechdrs[section].sh_addr);
898}
899
900static int addend_386_rel(struct elf_info *elf, int rsection, Elf_Rela *r)
901{
902 unsigned int r_typ = ELF_R_TYPE(r->r_info);
903 unsigned int *location = reloc_location(elf, rsection, r);
904
905 switch (r_typ) {
906 case R_386_32:
907 r->r_addend = TO_NATIVE(*location);
908 break;
909 case R_386_PC32:
910 r->r_addend = TO_NATIVE(*location) + 4;
911 /* For CONFIG_RELOCATABLE=y */
912 if (elf->hdr->e_type == ET_EXEC)
913 r->r_addend += r->r_offset;
914 break;
915 }
916 return 0;
917}
918
Sam Ravnborg56a974f2007-07-16 22:39:35 +0200919static int addend_arm_rel(struct elf_info *elf, int rsection, Elf_Rela *r)
920{
921 unsigned int r_typ = ELF_R_TYPE(r->r_info);
922
923 switch (r_typ) {
924 case R_ARM_ABS32:
925 /* From ARM ABI: (S + A) | T */
926 r->r_addend = (int)(long)(elf->symtab_start + ELF_R_SYM(r->r_info));
927 break;
928 case R_ARM_PC24:
929 /* From ARM ABI: ((S + A) | T) - P */
930 r->r_addend = (int)(long)(elf->hdr + elf->sechdrs[rsection].sh_offset +
931 (r->r_offset - elf->sechdrs[rsection].sh_addr));
932 break;
933 default:
934 return 1;
935 }
936 return 0;
937}
938
Atsushi Nemotoae4ac122007-05-22 18:27:39 +0900939static int addend_mips_rel(struct elf_info *elf, int rsection, Elf_Rela *r)
940{
941 unsigned int r_typ = ELF_R_TYPE(r->r_info);
942 unsigned int *location = reloc_location(elf, rsection, r);
943 unsigned int inst;
944
945 if (r_typ == R_MIPS_HI16)
946 return 1; /* skip this */
947 inst = TO_NATIVE(*location);
948 switch (r_typ) {
949 case R_MIPS_LO16:
950 r->r_addend = inst & 0xffff;
951 break;
952 case R_MIPS_26:
953 r->r_addend = (inst & 0x03ffffff) << 2;
954 break;
955 case R_MIPS_32:
956 r->r_addend = inst;
957 break;
958 }
959 return 0;
960}
961
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100962/**
963 * A module includes a number of sections that are discarded
964 * either when loaded or when used as built-in.
965 * For loaded modules all functions marked __init and all data
966 * marked __initdata will be discarded when the module has been intialized.
967 * Likewise for modules used built-in the sections marked __exit
968 * are discarded because __exit marked function are supposed to be called
969 * only when a moduel is unloaded which never happes for built-in modules.
970 * The check_sec_ref() function traverses all relocation records
971 * to find all references to a section that reference a section that will
972 * be discarded and warns about it.
973 **/
974static void check_sec_ref(struct module *mod, const char *modname,
975 struct elf_info *elf,
976 int section(const char*),
977 int section_ref_ok(const char *))
978{
979 int i;
980 Elf_Sym *sym;
981 Elf_Ehdr *hdr = elf->hdr;
982 Elf_Shdr *sechdrs = elf->sechdrs;
983 const char *secstrings = (void *)hdr +
984 sechdrs[hdr->e_shstrndx].sh_offset;
Sam Ravnborg62070fa2006-03-03 16:46:04 +0100985
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100986 /* Walk through all sections */
987 for (i = 0; i < hdr->e_shnum; i++) {
Atsushi Nemoto2c1a51f2006-05-20 15:00:26 -0700988 const char *name = secstrings + sechdrs[i].sh_name;
989 const char *secname;
990 Elf_Rela r;
Atsushi Nemotoeae07ac2006-05-20 15:00:28 -0700991 unsigned int r_sym;
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100992 /* We want to process only relocation sections and not .init */
Atsushi Nemoto2c1a51f2006-05-20 15:00:26 -0700993 if (sechdrs[i].sh_type == SHT_RELA) {
994 Elf_Rela *rela;
995 Elf_Rela *start = (void *)hdr + sechdrs[i].sh_offset;
996 Elf_Rela *stop = (void*)start + sechdrs[i].sh_size;
997 name += strlen(".rela");
998 if (section_ref_ok(name))
Sam Ravnborgb39927c2006-02-17 22:42:02 +0100999 continue;
1000
Atsushi Nemoto2c1a51f2006-05-20 15:00:26 -07001001 for (rela = start; rela < stop; rela++) {
1002 r.r_offset = TO_NATIVE(rela->r_offset);
Atsushi Nemotoeae07ac2006-05-20 15:00:28 -07001003#if KERNEL_ELFCLASS == ELFCLASS64
1004 if (hdr->e_machine == EM_MIPS) {
Atsushi Nemotoae4ac122007-05-22 18:27:39 +09001005 unsigned int r_typ;
Atsushi Nemotoeae07ac2006-05-20 15:00:28 -07001006 r_sym = ELF64_MIPS_R_SYM(rela->r_info);
1007 r_sym = TO_NATIVE(r_sym);
Atsushi Nemotoae4ac122007-05-22 18:27:39 +09001008 r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
1009 r.r_info = ELF64_R_INFO(r_sym, r_typ);
Atsushi Nemotoeae07ac2006-05-20 15:00:28 -07001010 } else {
1011 r.r_info = TO_NATIVE(rela->r_info);
1012 r_sym = ELF_R_SYM(r.r_info);
1013 }
1014#else
1015 r.r_info = TO_NATIVE(rela->r_info);
1016 r_sym = ELF_R_SYM(r.r_info);
1017#endif
Atsushi Nemoto2c1a51f2006-05-20 15:00:26 -07001018 r.r_addend = TO_NATIVE(rela->r_addend);
Atsushi Nemotoeae07ac2006-05-20 15:00:28 -07001019 sym = elf->symtab_start + r_sym;
Atsushi Nemoto2c1a51f2006-05-20 15:00:26 -07001020 /* Skip special sections */
1021 if (sym->st_shndx >= SHN_LORESERVE)
1022 continue;
1023
1024 secname = secstrings +
1025 sechdrs[sym->st_shndx].sh_name;
1026 if (section(secname))
1027 warn_sec_mismatch(modname, name,
1028 elf, sym, r);
1029 }
1030 } else if (sechdrs[i].sh_type == SHT_REL) {
1031 Elf_Rel *rel;
1032 Elf_Rel *start = (void *)hdr + sechdrs[i].sh_offset;
1033 Elf_Rel *stop = (void*)start + sechdrs[i].sh_size;
1034 name += strlen(".rel");
1035 if (section_ref_ok(name))
1036 continue;
1037
1038 for (rel = start; rel < stop; rel++) {
1039 r.r_offset = TO_NATIVE(rel->r_offset);
Atsushi Nemotoeae07ac2006-05-20 15:00:28 -07001040#if KERNEL_ELFCLASS == ELFCLASS64
1041 if (hdr->e_machine == EM_MIPS) {
Atsushi Nemotoae4ac122007-05-22 18:27:39 +09001042 unsigned int r_typ;
Atsushi Nemotoeae07ac2006-05-20 15:00:28 -07001043 r_sym = ELF64_MIPS_R_SYM(rel->r_info);
1044 r_sym = TO_NATIVE(r_sym);
Atsushi Nemotoae4ac122007-05-22 18:27:39 +09001045 r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
1046 r.r_info = ELF64_R_INFO(r_sym, r_typ);
Atsushi Nemotoeae07ac2006-05-20 15:00:28 -07001047 } else {
1048 r.r_info = TO_NATIVE(rel->r_info);
1049 r_sym = ELF_R_SYM(r.r_info);
1050 }
1051#else
1052 r.r_info = TO_NATIVE(rel->r_info);
1053 r_sym = ELF_R_SYM(r.r_info);
1054#endif
Atsushi Nemoto2c1a51f2006-05-20 15:00:26 -07001055 r.r_addend = 0;
Atsushi Nemotoae4ac122007-05-22 18:27:39 +09001056 switch (hdr->e_machine) {
1057 case EM_386:
1058 if (addend_386_rel(elf, i, &r))
1059 continue;
1060 break;
Sam Ravnborg56a974f2007-07-16 22:39:35 +02001061 case EM_ARM:
1062 if(addend_arm_rel(elf, i, &r))
1063 continue;
1064 break;
Atsushi Nemotoae4ac122007-05-22 18:27:39 +09001065 case EM_MIPS:
1066 if (addend_mips_rel(elf, i, &r))
1067 continue;
1068 break;
1069 }
Atsushi Nemotoeae07ac2006-05-20 15:00:28 -07001070 sym = elf->symtab_start + r_sym;
Atsushi Nemoto2c1a51f2006-05-20 15:00:26 -07001071 /* Skip special sections */
1072 if (sym->st_shndx >= SHN_LORESERVE)
1073 continue;
1074
1075 secname = secstrings +
1076 sechdrs[sym->st_shndx].sh_name;
1077 if (section(secname))
1078 warn_sec_mismatch(modname, name,
1079 elf, sym, r);
1080 }
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001081 }
1082 }
1083}
1084
Sam Ravnborg10872472007-06-02 21:18:51 +02001085/*
1086 * Identify sections from which references to either a
1087 * .init or a .exit section is OK.
1088 *
1089 * [OPD] Keith Ownes <kaos@sgi.com> commented:
1090 * For our future {in}sanity, add a comment that this is the ppc .opd
1091 * section, not the ia64 .opd section.
1092 * ia64 .opd should not point to discarded sections.
1093 * [.rodata] like for .init.text we ignore .rodata references -same reason
Sam Ravnborg1d8af552007-06-03 00:41:22 +02001094 */
Sam Ravnborg10872472007-06-02 21:18:51 +02001095static int initexit_section_ref_ok(const char *name)
1096{
1097 const char **s;
1098 /* Absolute section names */
1099 const char *namelist1[] = {
1100 "__bug_table", /* used by powerpc for BUG() */
1101 "__ex_table",
1102 ".altinstructions",
1103 ".cranges", /* used by sh64 */
1104 ".fixup",
Sam Ravnborg1d8af552007-06-03 00:41:22 +02001105 ".machvec", /* ia64 + powerpc uses these */
1106 ".machine.desc",
Sam Ravnborg10872472007-06-02 21:18:51 +02001107 ".opd", /* See comment [OPD] */
1108 ".parainstructions",
1109 ".pdr",
1110 ".plt", /* seen on ARCH=um build on x86_64. Harmless */
1111 ".smp_locks",
1112 ".stab",
Al Viro3a5df1d2007-07-20 04:32:48 +01001113 ".m68k_fixup",
Sam Ravnborg10872472007-06-02 21:18:51 +02001114 NULL
1115 };
1116 /* Start of section names */
1117 const char *namelist2[] = {
1118 ".debug",
1119 ".eh_frame",
1120 ".note", /* ignore ELF notes - may contain anything */
1121 ".got", /* powerpc - global offset table */
1122 ".toc", /* powerpc - table of contents */
1123 NULL
1124 };
1125 /* part of section name */
1126 const char *namelist3 [] = {
1127 ".unwind", /* Sample: IA_64.unwind.exit.text */
1128 NULL
1129 };
1130
1131 for (s = namelist1; *s; s++)
1132 if (strcmp(*s, name) == 0)
1133 return 1;
1134 for (s = namelist2; *s; s++)
1135 if (strncmp(*s, name, strlen(*s)) == 0)
1136 return 1;
1137 for (s = namelist3; *s; s++)
1138 if (strstr(name, *s) != NULL)
1139 return 1;
1140 return 0;
1141}
1142
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001143
Sam Ravnborg10872472007-06-02 21:18:51 +02001144/*
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001145 * Identify sections from which references to a .init section is OK.
Sam Ravnborg62070fa2006-03-03 16:46:04 +01001146 *
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001147 * Unfortunately references to read only data that referenced .init
1148 * sections had to be excluded. Almost all of these are false
1149 * positives, they are created by gcc. The downside of excluding rodata
1150 * is that there really are some user references from rodata to
1151 * init code, e.g. drivers/video/vgacon.c:
Sam Ravnborg62070fa2006-03-03 16:46:04 +01001152 *
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001153 * const struct consw vga_con = {
1154 * con_startup: vgacon_startup,
1155 *
1156 * where vgacon_startup is __init. If you want to wade through the false
1157 * positives, take out the check for rodata.
Sam Ravnborg10872472007-06-02 21:18:51 +02001158 */
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001159static int init_section_ref_ok(const char *name)
1160{
1161 const char **s;
1162 /* Absolute section names */
1163 const char *namelist1[] = {
Ralf Baechleeec73e82007-07-10 09:16:32 +01001164 "__dbe_table", /* MIPS generate these */
Benjamin Herrenschmidt21c4ff82006-10-20 11:47:19 +10001165 "__ftr_fixup", /* powerpc cpu feature fixup */
1166 "__fw_ftr_fixup", /* powerpc firmware feature fixup */
Sam Ravnborg10872472007-06-02 21:18:51 +02001167 "__param",
1168 ".data.rel.ro", /* used by parisc64 */
1169 ".init",
1170 ".text.lock",
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001171 NULL
1172 };
1173 /* Start of section names */
1174 const char *namelist2[] = {
1175 ".init.",
Sam Ravnborg10872472007-06-02 21:18:51 +02001176 ".pci_fixup",
Matthew Wilcox742433b2007-02-05 16:34:00 -08001177 ".rodata",
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001178 NULL
1179 };
Sam Ravnborg10872472007-06-02 21:18:51 +02001180
1181 if (initexit_section_ref_ok(name))
1182 return 1;
Sam Ravnborg6e101332006-02-22 21:24:50 +01001183
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001184 for (s = namelist1; *s; s++)
1185 if (strcmp(*s, name) == 0)
1186 return 1;
Sam Ravnborg62070fa2006-03-03 16:46:04 +01001187 for (s = namelist2; *s; s++)
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001188 if (strncmp(*s, name, strlen(*s)) == 0)
1189 return 1;
Sam Ravnborg10872472007-06-02 21:18:51 +02001190
1191 /* If section name ends with ".init" we allow references
1192 * as is the case with .initcallN.init, .early_param.init, .taglist.init etc
1193 */
Al Viro468d9492006-06-23 23:22:43 +01001194 if (strrcmp(name, ".init") == 0)
1195 return 1;
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001196 return 0;
1197}
1198
1199/*
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001200 * Identify sections from which references to a .exit section is OK.
Sam Ravnborg10872472007-06-02 21:18:51 +02001201 */
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001202static int exit_section_ref_ok(const char *name)
1203{
1204 const char **s;
1205 /* Absolute section names */
1206 const char *namelist1[] = {
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001207 ".exit.data",
Sam Ravnborg10872472007-06-02 21:18:51 +02001208 ".exit.text",
1209 ".exitcall.exit",
Sam Ravnborg5ecdd0f2006-04-14 23:54:13 +02001210 ".rodata",
Sam Ravnborg6e101332006-02-22 21:24:50 +01001211 NULL
1212 };
Sam Ravnborg62070fa2006-03-03 16:46:04 +01001213
Sam Ravnborg10872472007-06-02 21:18:51 +02001214 if (initexit_section_ref_ok(name))
1215 return 1;
1216
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001217 for (s = namelist1; *s; s++)
1218 if (strcmp(*s, name) == 0)
1219 return 1;
Sam Ravnborgb39927c2006-02-17 22:42:02 +01001220 return 0;
1221}
1222
Sam Ravnborg5c3ead82006-01-28 17:19:35 +01001223static void read_symbols(char *modname)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001224{
1225 const char *symname;
1226 char *version;
Sam Ravnborgb817f6f2006-06-09 21:53:55 +02001227 char *license;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001228 struct module *mod;
1229 struct elf_info info = { };
1230 Elf_Sym *sym;
1231
Sam Ravnborg85bd2fd2007-02-26 15:33:52 +01001232 if (!parse_elf(&info, modname))
1233 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001234
1235 mod = new_module(modname);
1236
1237 /* When there's no vmlinux, don't print warnings about
1238 * unresolved symbols (since there'll be too many ;) */
1239 if (is_vmlinux(modname)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001240 have_vmlinux = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241 mod->skip = 1;
1242 }
1243
Sam Ravnborgb817f6f2006-06-09 21:53:55 +02001244 license = get_modinfo(info.modinfo, info.modinfo_len, "license");
1245 while (license) {
1246 if (license_is_gpl_compatible(license))
1247 mod->gpl_compatible = 1;
1248 else {
1249 mod->gpl_compatible = 0;
1250 break;
1251 }
1252 license = get_next_modinfo(info.modinfo, info.modinfo_len,
1253 "license", license);
1254 }
1255
Linus Torvalds1da177e2005-04-16 15:20:36 -07001256 for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
1257 symname = info.strtab + sym->st_name;
1258
1259 handle_modversions(mod, &info, sym, symname);
1260 handle_moddevtable(mod, &info, sym, symname);
1261 }
Sam Ravnborg8d8d8282007-07-20 22:36:56 +02001262 if (is_vmlinux(modname) && vmlinux_section_warnings) {
1263 check_sec_ref(mod, modname, &info, init_section, init_section_ref_ok);
1264 check_sec_ref(mod, modname, &info, exit_section, exit_section_ref_ok);
1265 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001266
1267 version = get_modinfo(info.modinfo, info.modinfo_len, "version");
1268 if (version)
1269 maybe_frob_rcs_version(modname, version, info.modinfo,
1270 version - (char *)info.hdr);
1271 if (version || (all_versions && !is_vmlinux(modname)))
1272 get_src_version(modname, mod->srcversion,
1273 sizeof(mod->srcversion)-1);
1274
1275 parse_elf_finish(&info);
1276
1277 /* Our trick to get versioning for struct_module - it's
1278 * never passed as an argument to an exported function, so
1279 * the automatic versioning doesn't pick it up, but it's really
1280 * important anyhow */
1281 if (modversions)
1282 mod->unres = alloc_symbol("struct_module", 0, mod->unres);
1283}
1284
1285#define SZ 500
1286
1287/* We first write the generated file into memory using the
1288 * following helper, then compare to the file on disk and
1289 * only update the later if anything changed */
1290
Sam Ravnborg5c3ead82006-01-28 17:19:35 +01001291void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
1292 const char *fmt, ...)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001293{
1294 char tmp[SZ];
1295 int len;
1296 va_list ap;
Sam Ravnborg62070fa2006-03-03 16:46:04 +01001297
Linus Torvalds1da177e2005-04-16 15:20:36 -07001298 va_start(ap, fmt);
1299 len = vsnprintf(tmp, SZ, fmt, ap);
Sam Ravnborg7670f022006-03-16 23:04:08 -08001300 buf_write(buf, tmp, len);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001301 va_end(ap);
1302}
1303
Sam Ravnborg5c3ead82006-01-28 17:19:35 +01001304void buf_write(struct buffer *buf, const char *s, int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305{
1306 if (buf->size - buf->pos < len) {
Sam Ravnborg7670f022006-03-16 23:04:08 -08001307 buf->size += len + SZ;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001308 buf->p = realloc(buf->p, buf->size);
1309 }
1310 strncpy(buf->p + buf->pos, s, len);
1311 buf->pos += len;
1312}
1313
Sam Ravnborgc96fca22006-07-01 11:44:23 +02001314static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
1315{
1316 const char *e = is_vmlinux(m) ?"":".ko";
1317
1318 switch (exp) {
1319 case export_gpl:
1320 fatal("modpost: GPL-incompatible module %s%s "
1321 "uses GPL-only symbol '%s'\n", m, e, s);
1322 break;
1323 case export_unused_gpl:
1324 fatal("modpost: GPL-incompatible module %s%s "
1325 "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
1326 break;
1327 case export_gpl_future:
1328 warn("modpost: GPL-incompatible module %s%s "
1329 "uses future GPL-only symbol '%s'\n", m, e, s);
1330 break;
1331 case export_plain:
1332 case export_unused:
1333 case export_unknown:
1334 /* ignore */
1335 break;
1336 }
1337}
1338
1339static void check_for_unused(enum export exp, const char* m, const char* s)
1340{
1341 const char *e = is_vmlinux(m) ?"":".ko";
1342
1343 switch (exp) {
1344 case export_unused:
1345 case export_unused_gpl:
1346 warn("modpost: module %s%s "
1347 "uses symbol '%s' marked UNUSED\n", m, e, s);
1348 break;
1349 default:
1350 /* ignore */
1351 break;
1352 }
1353}
1354
1355static void check_exports(struct module *mod)
Sam Ravnborgb817f6f2006-06-09 21:53:55 +02001356{
1357 struct symbol *s, *exp;
1358
1359 for (s = mod->unres; s; s = s->next) {
Andrew Morton6449bd62006-06-09 20:45:06 -07001360 const char *basename;
Sam Ravnborgb817f6f2006-06-09 21:53:55 +02001361 exp = find_symbol(s->name);
1362 if (!exp || exp->module == mod)
1363 continue;
Andrew Morton6449bd62006-06-09 20:45:06 -07001364 basename = strrchr(mod->name, '/');
Sam Ravnborgb817f6f2006-06-09 21:53:55 +02001365 if (basename)
1366 basename++;
Sam Ravnborgc96fca22006-07-01 11:44:23 +02001367 else
1368 basename = mod->name;
1369 if (!mod->gpl_compatible)
1370 check_for_gpl_usage(exp->export, basename, exp->name);
1371 check_for_unused(exp->export, basename, exp->name);
Sam Ravnborgb817f6f2006-06-09 21:53:55 +02001372 }
1373}
1374
Sam Ravnborg5c3ead82006-01-28 17:19:35 +01001375/**
1376 * Header for the generated file
1377 **/
1378static void add_header(struct buffer *b, struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001379{
1380 buf_printf(b, "#include <linux/module.h>\n");
1381 buf_printf(b, "#include <linux/vermagic.h>\n");
1382 buf_printf(b, "#include <linux/compiler.h>\n");
1383 buf_printf(b, "\n");
1384 buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
1385 buf_printf(b, "\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001386 buf_printf(b, "struct module __this_module\n");
1387 buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
Ustyugov Romanf83b5e32005-09-23 08:42:11 +04001388 buf_printf(b, " .name = KBUILD_MODNAME,\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001389 if (mod->has_init)
1390 buf_printf(b, " .init = init_module,\n");
1391 if (mod->has_cleanup)
1392 buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
1393 " .exit = cleanup_module,\n"
1394 "#endif\n");
Roman Zippele61a1c12007-05-09 02:35:15 -07001395 buf_printf(b, " .arch = MODULE_ARCH_INIT,\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001396 buf_printf(b, "};\n");
1397}
1398
Sam Ravnborg5c3ead82006-01-28 17:19:35 +01001399/**
1400 * Record CRCs for unresolved symbols
1401 **/
Kirill Korotaevc53ddac2006-09-07 13:08:54 -07001402static int add_versions(struct buffer *b, struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001403{
1404 struct symbol *s, *exp;
Kirill Korotaevc53ddac2006-09-07 13:08:54 -07001405 int err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001406
1407 for (s = mod->unres; s; s = s->next) {
1408 exp = find_symbol(s->name);
1409 if (!exp || exp->module == mod) {
Kirill Korotaevc53ddac2006-09-07 13:08:54 -07001410 if (have_vmlinux && !s->weak) {
Matthew Wilcox2a116652006-10-07 05:35:32 -06001411 if (warn_unresolved) {
1412 warn("\"%s\" [%s.ko] undefined!\n",
1413 s->name, mod->name);
1414 } else {
1415 merror("\"%s\" [%s.ko] undefined!\n",
1416 s->name, mod->name);
1417 err = 1;
1418 }
Kirill Korotaevc53ddac2006-09-07 13:08:54 -07001419 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001420 continue;
1421 }
1422 s->module = exp->module;
1423 s->crc_valid = exp->crc_valid;
1424 s->crc = exp->crc;
1425 }
1426
1427 if (!modversions)
Kirill Korotaevc53ddac2006-09-07 13:08:54 -07001428 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001429
1430 buf_printf(b, "\n");
1431 buf_printf(b, "static const struct modversion_info ____versions[]\n");
1432 buf_printf(b, "__attribute_used__\n");
1433 buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n");
1434
1435 for (s = mod->unres; s; s = s->next) {
1436 if (!s->module) {
1437 continue;
1438 }
1439 if (!s->crc_valid) {
Sam Ravnborgcb805142006-01-28 16:57:26 +01001440 warn("\"%s\" [%s.ko] has no CRC!\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001441 s->name, mod->name);
1442 continue;
1443 }
1444 buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name);
1445 }
1446
1447 buf_printf(b, "};\n");
Kirill Korotaevc53ddac2006-09-07 13:08:54 -07001448
1449 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001450}
1451
Sam Ravnborg5c3ead82006-01-28 17:19:35 +01001452static void add_depends(struct buffer *b, struct module *mod,
1453 struct module *modules)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454{
1455 struct symbol *s;
1456 struct module *m;
1457 int first = 1;
1458
1459 for (m = modules; m; m = m->next) {
1460 m->seen = is_vmlinux(m->name);
1461 }
1462
1463 buf_printf(b, "\n");
1464 buf_printf(b, "static const char __module_depends[]\n");
1465 buf_printf(b, "__attribute_used__\n");
1466 buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n");
1467 buf_printf(b, "\"depends=");
1468 for (s = mod->unres; s; s = s->next) {
Sam Ravnborga61b2df2007-02-26 19:46:52 +01001469 const char *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001470 if (!s->module)
1471 continue;
1472
1473 if (s->module->seen)
1474 continue;
1475
1476 s->module->seen = 1;
Sam Ravnborga61b2df2007-02-26 19:46:52 +01001477 if ((p = strrchr(s->module->name, '/')) != NULL)
1478 p++;
1479 else
1480 p = s->module->name;
1481 buf_printf(b, "%s%s", first ? "" : ",", p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001482 first = 0;
1483 }
1484 buf_printf(b, "\";\n");
1485}
1486
Sam Ravnborg5c3ead82006-01-28 17:19:35 +01001487static void add_srcversion(struct buffer *b, struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001488{
1489 if (mod->srcversion[0]) {
1490 buf_printf(b, "\n");
1491 buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
1492 mod->srcversion);
1493 }
1494}
1495
Sam Ravnborg5c3ead82006-01-28 17:19:35 +01001496static void write_if_changed(struct buffer *b, const char *fname)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001497{
1498 char *tmp;
1499 FILE *file;
1500 struct stat st;
1501
1502 file = fopen(fname, "r");
1503 if (!file)
1504 goto write;
1505
1506 if (fstat(fileno(file), &st) < 0)
1507 goto close_write;
1508
1509 if (st.st_size != b->pos)
1510 goto close_write;
1511
1512 tmp = NOFAIL(malloc(b->pos));
1513 if (fread(tmp, 1, b->pos, file) != b->pos)
1514 goto free_write;
1515
1516 if (memcmp(tmp, b->p, b->pos) != 0)
1517 goto free_write;
1518
1519 free(tmp);
1520 fclose(file);
1521 return;
1522
1523 free_write:
1524 free(tmp);
1525 close_write:
1526 fclose(file);
1527 write:
1528 file = fopen(fname, "w");
1529 if (!file) {
1530 perror(fname);
1531 exit(1);
1532 }
1533 if (fwrite(b->p, 1, b->pos, file) != b->pos) {
1534 perror(fname);
1535 exit(1);
1536 }
1537 fclose(file);
1538}
1539
Ram Paibd5cbce2006-06-08 22:12:53 -07001540/* parse Module.symvers file. line format:
Sam Ravnborg534b89a2006-07-01 10:10:19 +02001541 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
Ram Paibd5cbce2006-06-08 22:12:53 -07001542 **/
Sam Ravnborg040fcc82006-01-28 22:15:55 +01001543static void read_dump(const char *fname, unsigned int kernel)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001544{
1545 unsigned long size, pos = 0;
1546 void *file = grab_file(fname, &size);
1547 char *line;
1548
1549 if (!file)
1550 /* No symbol versions, silently ignore */
1551 return;
1552
1553 while ((line = get_next_line(&pos, file, size))) {
Sam Ravnborg534b89a2006-07-01 10:10:19 +02001554 char *symname, *modname, *d, *export, *end;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001555 unsigned int crc;
1556 struct module *mod;
Sam Ravnborg040fcc82006-01-28 22:15:55 +01001557 struct symbol *s;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001558
1559 if (!(symname = strchr(line, '\t')))
1560 goto fail;
1561 *symname++ = '\0';
1562 if (!(modname = strchr(symname, '\t')))
1563 goto fail;
1564 *modname++ = '\0';
Laurent Riffard9ac545b2006-06-11 08:02:06 +02001565 if ((export = strchr(modname, '\t')) != NULL)
Ram Paibd5cbce2006-06-08 22:12:53 -07001566 *export++ = '\0';
Sam Ravnborg534b89a2006-07-01 10:10:19 +02001567 if (export && ((end = strchr(export, '\t')) != NULL))
1568 *end = '\0';
Linus Torvalds1da177e2005-04-16 15:20:36 -07001569 crc = strtoul(line, &d, 16);
1570 if (*symname == '\0' || *modname == '\0' || *d != '\0')
1571 goto fail;
1572
1573 if (!(mod = find_module(modname))) {
1574 if (is_vmlinux(modname)) {
1575 have_vmlinux = 1;
1576 }
1577 mod = new_module(NOFAIL(strdup(modname)));
1578 mod->skip = 1;
1579 }
Ram Paibd5cbce2006-06-08 22:12:53 -07001580 s = sym_add_exported(symname, mod, export_no(export));
Sam Ravnborg8e70c452006-01-28 22:22:33 +01001581 s->kernel = kernel;
1582 s->preloaded = 1;
Ram Paibd5cbce2006-06-08 22:12:53 -07001583 sym_update_crc(symname, mod, crc, export_no(export));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001584 }
1585 return;
1586fail:
1587 fatal("parse error in symbol dump file\n");
1588}
1589
Sam Ravnborg040fcc82006-01-28 22:15:55 +01001590/* For normal builds always dump all symbols.
1591 * For external modules only dump symbols
1592 * that are not read from kernel Module.symvers.
1593 **/
1594static int dump_sym(struct symbol *sym)
1595{
1596 if (!external_module)
1597 return 1;
1598 if (sym->vmlinux || sym->kernel)
1599 return 0;
1600 return 1;
1601}
Sam Ravnborg62070fa2006-03-03 16:46:04 +01001602
Sam Ravnborg5c3ead82006-01-28 17:19:35 +01001603static void write_dump(const char *fname)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001604{
1605 struct buffer buf = { };
1606 struct symbol *symbol;
1607 int n;
1608
1609 for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
1610 symbol = symbolhash[n];
1611 while (symbol) {
Sam Ravnborg040fcc82006-01-28 22:15:55 +01001612 if (dump_sym(symbol))
Ram Paibd5cbce2006-06-08 22:12:53 -07001613 buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
Sam Ravnborg62070fa2006-03-03 16:46:04 +01001614 symbol->crc, symbol->name,
Ram Paibd5cbce2006-06-08 22:12:53 -07001615 symbol->module->name,
1616 export_str(symbol->export));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001617 symbol = symbol->next;
1618 }
1619 }
1620 write_if_changed(&buf, fname);
1621}
1622
Sam Ravnborg5c3ead82006-01-28 17:19:35 +01001623int main(int argc, char **argv)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001624{
1625 struct module *mod;
1626 struct buffer buf = { };
1627 char fname[SZ];
Sam Ravnborg040fcc82006-01-28 22:15:55 +01001628 char *kernel_read = NULL, *module_read = NULL;
1629 char *dump_write = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001630 int opt;
Kirill Korotaevc53ddac2006-09-07 13:08:54 -07001631 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001632
Sam Ravnborg8d8d8282007-07-20 22:36:56 +02001633 while ((opt = getopt(argc, argv, "i:I:mso:aw")) != -1) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001634 switch(opt) {
1635 case 'i':
Sam Ravnborg040fcc82006-01-28 22:15:55 +01001636 kernel_read = optarg;
1637 break;
1638 case 'I':
1639 module_read = optarg;
1640 external_module = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001641 break;
1642 case 'm':
1643 modversions = 1;
1644 break;
1645 case 'o':
1646 dump_write = optarg;
1647 break;
1648 case 'a':
1649 all_versions = 1;
1650 break;
Sam Ravnborg8d8d8282007-07-20 22:36:56 +02001651 case 's':
1652 vmlinux_section_warnings = 0;
1653 break;
Kirill Korotaevc53ddac2006-09-07 13:08:54 -07001654 case 'w':
1655 warn_unresolved = 1;
1656 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657 default:
1658 exit(1);
1659 }
1660 }
1661
Sam Ravnborg040fcc82006-01-28 22:15:55 +01001662 if (kernel_read)
1663 read_dump(kernel_read, 1);
1664 if (module_read)
1665 read_dump(module_read, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001666
1667 while (optind < argc) {
1668 read_symbols(argv[optind++]);
1669 }
1670
1671 for (mod = modules; mod; mod = mod->next) {
1672 if (mod->skip)
1673 continue;
Sam Ravnborgc96fca22006-07-01 11:44:23 +02001674 check_exports(mod);
Sam Ravnborgb817f6f2006-06-09 21:53:55 +02001675 }
1676
Kirill Korotaevc53ddac2006-09-07 13:08:54 -07001677 err = 0;
1678
Sam Ravnborgb817f6f2006-06-09 21:53:55 +02001679 for (mod = modules; mod; mod = mod->next) {
1680 if (mod->skip)
1681 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001682
1683 buf.pos = 0;
1684
1685 add_header(&buf, mod);
Kirill Korotaevc53ddac2006-09-07 13:08:54 -07001686 err |= add_versions(&buf, mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001687 add_depends(&buf, mod, modules);
1688 add_moddevtable(&buf, mod);
1689 add_srcversion(&buf, mod);
1690
1691 sprintf(fname, "%s.mod.c", mod->name);
1692 write_if_changed(&buf, fname);
1693 }
1694
1695 if (dump_write)
1696 write_dump(dump_write);
1697
Kirill Korotaevc53ddac2006-09-07 13:08:54 -07001698 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001699}