1 /* Postprocess module symbol versions
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
8 * This software may be used and distributed according to the terms
9 * of the GNU General Public License, incorporated herein by reference.
11 * Usage: modpost vmlinux module1.o module2.o ...
22 #include "../../include/generated/autoconf.h"
23 #include "../../include/linux/license.h"
24 #include "../../include/linux/export.h"
26 /* Are we using CONFIG_MODVERSIONS? */
27 static int modversions
= 0;
28 /* Warn about undefined symbols? (do so if we have vmlinux) */
29 static int have_vmlinux
= 0;
30 /* Is CONFIG_MODULE_SRCVERSION_ALL set? */
31 static int all_versions
= 0;
32 /* If we are modposting external module set to 1 */
33 static int external_module
= 0;
34 /* Warn about section mismatch in vmlinux if set to 1 */
35 static int vmlinux_section_warnings
= 1;
36 /* Only warn about unresolved symbols */
37 static int warn_unresolved
= 0;
38 /* How a symbol is exported */
39 static int sec_mismatch_count
= 0;
40 static int sec_mismatch_verbose
= 1;
41 static int sec_mismatch_fatal
= 0;
42 /* ignore missing files */
43 static int ignore_missing_files
;
46 export_plain
, export_unused
, export_gpl
,
47 export_unused_gpl
, export_gpl_future
, export_unknown
50 #define PRINTF __attribute__ ((format (printf, 1, 2)))
52 PRINTF
void fatal(const char *fmt
, ...)
56 fprintf(stderr
, "FATAL: ");
58 va_start(arglist
, fmt
);
59 vfprintf(stderr
, fmt
, arglist
);
65 PRINTF
void warn(const char *fmt
, ...)
69 fprintf(stderr
, "WARNING: ");
71 va_start(arglist
, fmt
);
72 vfprintf(stderr
, fmt
, arglist
);
76 PRINTF
void merror(const char *fmt
, ...)
80 fprintf(stderr
, "ERROR: ");
82 va_start(arglist
, fmt
);
83 vfprintf(stderr
, fmt
, arglist
);
87 static inline bool strends(const char *str
, const char *postfix
)
89 if (strlen(str
) < strlen(postfix
))
92 return strcmp(str
+ strlen(str
) - strlen(postfix
), postfix
) == 0;
95 static int is_vmlinux(const char *modname
)
99 myname
= strrchr(modname
, '/');
105 return (strcmp(myname
, "vmlinux") == 0) ||
106 (strcmp(myname
, "vmlinux.o") == 0);
109 void *do_nofail(void *ptr
, const char *expr
)
112 fatal("modpost: Memory allocation failure: %s.\n", expr
);
117 /* A list of all modules we processed */
118 static struct module
*modules
;
120 static struct module
*find_module(char *modname
)
124 for (mod
= modules
; mod
; mod
= mod
->next
)
125 if (strcmp(mod
->name
, modname
) == 0)
130 static struct module
*new_module(const char *modname
)
135 mod
= NOFAIL(malloc(sizeof(*mod
)));
136 memset(mod
, 0, sizeof(*mod
));
137 p
= NOFAIL(strdup(modname
));
139 /* strip trailing .o */
140 if (strends(p
, ".o")) {
141 p
[strlen(p
) - 2] = '\0';
147 mod
->gpl_compatible
= -1;
154 /* A hash of all exported symbols,
155 * struct symbol is also used for lists of unresolved symbols */
157 #define SYMBOL_HASH_SIZE 1024
161 struct module
*module
;
165 unsigned int vmlinux
:1; /* 1 if symbol is defined in vmlinux */
166 unsigned int kernel
:1; /* 1 if symbol is from kernel
167 * (only for external modules) **/
168 unsigned int preloaded
:1; /* 1 if symbol from Module.symvers, or crc */
169 enum export export
; /* Type of export */
173 static struct symbol
*symbolhash
[SYMBOL_HASH_SIZE
];
175 /* This is based on the hash agorithm from gdbm, via tdb */
176 static inline unsigned int tdb_hash(const char *name
)
178 unsigned value
; /* Used to compute the hash value. */
179 unsigned i
; /* Used to cycle through random values. */
181 /* Set the initial value from the key size. */
182 for (value
= 0x238F13AF * strlen(name
), i
= 0; name
[i
]; i
++)
183 value
= (value
+ (((unsigned char *)name
)[i
] << (i
*5 % 24)));
185 return (1103515243 * value
+ 12345);
189 * Allocate a new symbols for use in the hash of exported symbols or
190 * the list of unresolved symbols per module
192 static struct symbol
*alloc_symbol(const char *name
, unsigned int weak
,
195 struct symbol
*s
= NOFAIL(malloc(sizeof(*s
) + strlen(name
) + 1));
197 memset(s
, 0, sizeof(*s
));
198 strcpy(s
->name
, name
);
204 /* For the hash of exported symbols */
205 static struct symbol
*new_symbol(const char *name
, struct module
*module
,
211 hash
= tdb_hash(name
) % SYMBOL_HASH_SIZE
;
212 new = symbolhash
[hash
] = alloc_symbol(name
, 0, symbolhash
[hash
]);
213 new->module
= module
;
214 new->export
= export
;
218 static struct symbol
*find_symbol(const char *name
)
222 /* For our purposes, .foo matches foo. PPC64 needs this. */
226 for (s
= symbolhash
[tdb_hash(name
) % SYMBOL_HASH_SIZE
]; s
; s
= s
->next
) {
227 if (strcmp(s
->name
, name
) == 0)
233 static const struct {
237 { .str
= "EXPORT_SYMBOL", .export
= export_plain
},
238 { .str
= "EXPORT_UNUSED_SYMBOL", .export
= export_unused
},
239 { .str
= "EXPORT_SYMBOL_GPL", .export
= export_gpl
},
240 { .str
= "EXPORT_UNUSED_SYMBOL_GPL", .export
= export_unused_gpl
},
241 { .str
= "EXPORT_SYMBOL_GPL_FUTURE", .export
= export_gpl_future
},
242 { .str
= "(unknown)", .export
= export_unknown
},
246 static const char *export_str(enum export ex
)
248 return export_list
[ex
].str
;
251 static enum export
export_no(const char *s
)
256 return export_unknown
;
257 for (i
= 0; export_list
[i
].export
!= export_unknown
; i
++) {
258 if (strcmp(export_list
[i
].str
, s
) == 0)
259 return export_list
[i
].export
;
261 return export_unknown
;
264 static const char *sec_name(struct elf_info
*elf
, int secindex
);
266 #define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
268 static enum export
export_from_secname(struct elf_info
*elf
, unsigned int sec
)
270 const char *secname
= sec_name(elf
, sec
);
272 if (strstarts(secname
, "___ksymtab+"))
274 else if (strstarts(secname
, "___ksymtab_unused+"))
275 return export_unused
;
276 else if (strstarts(secname
, "___ksymtab_gpl+"))
278 else if (strstarts(secname
, "___ksymtab_unused_gpl+"))
279 return export_unused_gpl
;
280 else if (strstarts(secname
, "___ksymtab_gpl_future+"))
281 return export_gpl_future
;
283 return export_unknown
;
286 static enum export
export_from_sec(struct elf_info
*elf
, unsigned int sec
)
288 if (sec
== elf
->export_sec
)
290 else if (sec
== elf
->export_unused_sec
)
291 return export_unused
;
292 else if (sec
== elf
->export_gpl_sec
)
294 else if (sec
== elf
->export_unused_gpl_sec
)
295 return export_unused_gpl
;
296 else if (sec
== elf
->export_gpl_future_sec
)
297 return export_gpl_future
;
299 return export_unknown
;
303 * Add an exported symbol - it may have already been added without a
304 * CRC, in this case just update the CRC
306 static struct symbol
*sym_add_exported(const char *name
, struct module
*mod
,
309 struct symbol
*s
= find_symbol(name
);
312 s
= new_symbol(name
, mod
, export
);
315 warn("%s: '%s' exported twice. Previous export "
316 "was in %s%s\n", mod
->name
, name
,
318 is_vmlinux(s
->module
->name
) ?"":".ko");
320 /* In case Module.symvers was out of date */
325 s
->vmlinux
= is_vmlinux(mod
->name
);
331 static void sym_update_crc(const char *name
, struct module
*mod
,
332 unsigned int crc
, enum export export
)
334 struct symbol
*s
= find_symbol(name
);
337 s
= new_symbol(name
, mod
, export
);
338 /* Don't complain when we find it later. */
345 void *grab_file(const char *filename
, unsigned long *size
)
348 void *map
= MAP_FAILED
;
351 fd
= open(filename
, O_RDONLY
);
358 map
= mmap(NULL
, *size
, PROT_READ
|PROT_WRITE
, MAP_PRIVATE
, fd
, 0);
362 if (map
== MAP_FAILED
)
368 * Return a copy of the next line in a mmap'ed file.
369 * spaces in the beginning of the line is trimmed away.
370 * Return a pointer to a static buffer.
372 char *get_next_line(unsigned long *pos
, void *file
, unsigned long size
)
374 static char line
[4096];
377 signed char *p
= (signed char *)file
+ *pos
;
380 for (; *pos
< size
; (*pos
)++) {
381 if (skip
&& isspace(*p
)) {
386 if (*p
!= '\n' && (*pos
< size
)) {
390 break; /* Too long, stop */
401 void release_file(void *file
, unsigned long size
)
406 static int parse_elf(struct elf_info
*info
, const char *filename
)
412 const char *secstrings
;
413 unsigned int symtab_idx
= ~0U, symtab_shndx_idx
= ~0U;
415 hdr
= grab_file(filename
, &info
->size
);
417 if (ignore_missing_files
) {
418 fprintf(stderr
, "%s: %s (ignored)\n", filename
,
426 if (info
->size
< sizeof(*hdr
)) {
427 /* file too small, assume this is an empty .o file */
430 /* Is this a valid ELF file? */
431 if ((hdr
->e_ident
[EI_MAG0
] != ELFMAG0
) ||
432 (hdr
->e_ident
[EI_MAG1
] != ELFMAG1
) ||
433 (hdr
->e_ident
[EI_MAG2
] != ELFMAG2
) ||
434 (hdr
->e_ident
[EI_MAG3
] != ELFMAG3
)) {
435 /* Not an ELF file - silently ignore it */
438 /* Fix endianness in ELF header */
439 hdr
->e_type
= TO_NATIVE(hdr
->e_type
);
440 hdr
->e_machine
= TO_NATIVE(hdr
->e_machine
);
441 hdr
->e_version
= TO_NATIVE(hdr
->e_version
);
442 hdr
->e_entry
= TO_NATIVE(hdr
->e_entry
);
443 hdr
->e_phoff
= TO_NATIVE(hdr
->e_phoff
);
444 hdr
->e_shoff
= TO_NATIVE(hdr
->e_shoff
);
445 hdr
->e_flags
= TO_NATIVE(hdr
->e_flags
);
446 hdr
->e_ehsize
= TO_NATIVE(hdr
->e_ehsize
);
447 hdr
->e_phentsize
= TO_NATIVE(hdr
->e_phentsize
);
448 hdr
->e_phnum
= TO_NATIVE(hdr
->e_phnum
);
449 hdr
->e_shentsize
= TO_NATIVE(hdr
->e_shentsize
);
450 hdr
->e_shnum
= TO_NATIVE(hdr
->e_shnum
);
451 hdr
->e_shstrndx
= TO_NATIVE(hdr
->e_shstrndx
);
452 sechdrs
= (void *)hdr
+ hdr
->e_shoff
;
453 info
->sechdrs
= sechdrs
;
455 /* Check if file offset is correct */
456 if (hdr
->e_shoff
> info
->size
) {
457 fatal("section header offset=%lu in file '%s' is bigger than "
458 "filesize=%lu\n", (unsigned long)hdr
->e_shoff
,
459 filename
, info
->size
);
463 if (hdr
->e_shnum
== SHN_UNDEF
) {
465 * There are more than 64k sections,
466 * read count from .sh_size.
468 info
->num_sections
= TO_NATIVE(sechdrs
[0].sh_size
);
471 info
->num_sections
= hdr
->e_shnum
;
473 if (hdr
->e_shstrndx
== SHN_XINDEX
) {
474 info
->secindex_strings
= TO_NATIVE(sechdrs
[0].sh_link
);
477 info
->secindex_strings
= hdr
->e_shstrndx
;
480 /* Fix endianness in section headers */
481 for (i
= 0; i
< info
->num_sections
; i
++) {
482 sechdrs
[i
].sh_name
= TO_NATIVE(sechdrs
[i
].sh_name
);
483 sechdrs
[i
].sh_type
= TO_NATIVE(sechdrs
[i
].sh_type
);
484 sechdrs
[i
].sh_flags
= TO_NATIVE(sechdrs
[i
].sh_flags
);
485 sechdrs
[i
].sh_addr
= TO_NATIVE(sechdrs
[i
].sh_addr
);
486 sechdrs
[i
].sh_offset
= TO_NATIVE(sechdrs
[i
].sh_offset
);
487 sechdrs
[i
].sh_size
= TO_NATIVE(sechdrs
[i
].sh_size
);
488 sechdrs
[i
].sh_link
= TO_NATIVE(sechdrs
[i
].sh_link
);
489 sechdrs
[i
].sh_info
= TO_NATIVE(sechdrs
[i
].sh_info
);
490 sechdrs
[i
].sh_addralign
= TO_NATIVE(sechdrs
[i
].sh_addralign
);
491 sechdrs
[i
].sh_entsize
= TO_NATIVE(sechdrs
[i
].sh_entsize
);
493 /* Find symbol table. */
494 secstrings
= (void *)hdr
+ sechdrs
[info
->secindex_strings
].sh_offset
;
495 for (i
= 1; i
< info
->num_sections
; i
++) {
497 int nobits
= sechdrs
[i
].sh_type
== SHT_NOBITS
;
499 if (!nobits
&& sechdrs
[i
].sh_offset
> info
->size
) {
500 fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
501 "sizeof(*hrd)=%zu\n", filename
,
502 (unsigned long)sechdrs
[i
].sh_offset
,
506 secname
= secstrings
+ sechdrs
[i
].sh_name
;
507 if (strcmp(secname
, ".modinfo") == 0) {
509 fatal("%s has NOBITS .modinfo\n", filename
);
510 info
->modinfo
= (void *)hdr
+ sechdrs
[i
].sh_offset
;
511 info
->modinfo_len
= sechdrs
[i
].sh_size
;
512 } else if (strcmp(secname
, "__ksymtab") == 0)
513 info
->export_sec
= i
;
514 else if (strcmp(secname
, "__ksymtab_unused") == 0)
515 info
->export_unused_sec
= i
;
516 else if (strcmp(secname
, "__ksymtab_gpl") == 0)
517 info
->export_gpl_sec
= i
;
518 else if (strcmp(secname
, "__ksymtab_unused_gpl") == 0)
519 info
->export_unused_gpl_sec
= i
;
520 else if (strcmp(secname
, "__ksymtab_gpl_future") == 0)
521 info
->export_gpl_future_sec
= i
;
523 if (sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
524 unsigned int sh_link_idx
;
526 info
->symtab_start
= (void *)hdr
+
527 sechdrs
[i
].sh_offset
;
528 info
->symtab_stop
= (void *)hdr
+
529 sechdrs
[i
].sh_offset
+ sechdrs
[i
].sh_size
;
530 sh_link_idx
= sechdrs
[i
].sh_link
;
531 info
->strtab
= (void *)hdr
+
532 sechdrs
[sh_link_idx
].sh_offset
;
535 /* 32bit section no. table? ("more than 64k sections") */
536 if (sechdrs
[i
].sh_type
== SHT_SYMTAB_SHNDX
) {
537 symtab_shndx_idx
= i
;
538 info
->symtab_shndx_start
= (void *)hdr
+
539 sechdrs
[i
].sh_offset
;
540 info
->symtab_shndx_stop
= (void *)hdr
+
541 sechdrs
[i
].sh_offset
+ sechdrs
[i
].sh_size
;
544 if (!info
->symtab_start
)
545 fatal("%s has no symtab?\n", filename
);
547 /* Fix endianness in symbols */
548 for (sym
= info
->symtab_start
; sym
< info
->symtab_stop
; sym
++) {
549 sym
->st_shndx
= TO_NATIVE(sym
->st_shndx
);
550 sym
->st_name
= TO_NATIVE(sym
->st_name
);
551 sym
->st_value
= TO_NATIVE(sym
->st_value
);
552 sym
->st_size
= TO_NATIVE(sym
->st_size
);
555 if (symtab_shndx_idx
!= ~0U) {
557 if (symtab_idx
!= sechdrs
[symtab_shndx_idx
].sh_link
)
558 fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
559 filename
, sechdrs
[symtab_shndx_idx
].sh_link
,
562 for (p
= info
->symtab_shndx_start
; p
< info
->symtab_shndx_stop
;
570 static void parse_elf_finish(struct elf_info
*info
)
572 release_file(info
->hdr
, info
->size
);
575 static int ignore_undef_symbol(struct elf_info
*info
, const char *symname
)
577 /* ignore __this_module, it will be resolved shortly */
578 if (strcmp(symname
, VMLINUX_SYMBOL_STR(__this_module
)) == 0)
580 /* ignore global offset table */
581 if (strcmp(symname
, "_GLOBAL_OFFSET_TABLE_") == 0)
583 if (info
->hdr
->e_machine
== EM_PPC
)
584 /* Special register function linked on all modules during final link of .ko */
585 if (strncmp(symname
, "_restgpr_", sizeof("_restgpr_") - 1) == 0 ||
586 strncmp(symname
, "_savegpr_", sizeof("_savegpr_") - 1) == 0 ||
587 strncmp(symname
, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
588 strncmp(symname
, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0 ||
589 strncmp(symname
, "_restvr_", sizeof("_restvr_") - 1) == 0 ||
590 strncmp(symname
, "_savevr_", sizeof("_savevr_") - 1) == 0)
592 if (info
->hdr
->e_machine
== EM_PPC64
)
593 /* Special register function linked on all modules during final link of .ko */
594 if (strncmp(symname
, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 ||
595 strncmp(symname
, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0 ||
596 strncmp(symname
, "_restvr_", sizeof("_restvr_") - 1) == 0 ||
597 strncmp(symname
, "_savevr_", sizeof("_savevr_") - 1) == 0 ||
598 strcmp(symname
, ".TOC.") == 0)
600 /* Do not ignore this symbol */
604 #define CRC_PFX VMLINUX_SYMBOL_STR(__crc_)
605 #define KSYMTAB_PFX VMLINUX_SYMBOL_STR(__ksymtab_)
607 static void handle_modversions(struct module
*mod
, struct elf_info
*info
,
608 Elf_Sym
*sym
, const char *symname
)
614 if ((!is_vmlinux(mod
->name
) || mod
->is_dot_o
) &&
615 strncmp(symname
, "__ksymtab", 9) == 0)
616 export
= export_from_secname(info
, get_secindex(info
, sym
));
618 export
= export_from_sec(info
, get_secindex(info
, sym
));
621 if (strncmp(symname
, CRC_PFX
, strlen(CRC_PFX
)) == 0) {
623 crc
= (unsigned int) sym
->st_value
;
624 if (sym
->st_shndx
!= SHN_UNDEF
&& sym
->st_shndx
!= SHN_ABS
) {
627 /* symbol points to the CRC in the ELF object */
628 crcp
= (void *)info
->hdr
+ sym
->st_value
+
629 info
->sechdrs
[sym
->st_shndx
].sh_offset
-
630 (info
->hdr
->e_type
!= ET_REL
?
631 info
->sechdrs
[sym
->st_shndx
].sh_addr
: 0);
634 sym_update_crc(symname
+ strlen(CRC_PFX
), mod
, crc
,
638 switch (sym
->st_shndx
) {
640 if (!strncmp(symname
, "__gnu_lto_", sizeof("__gnu_lto_")-1)) {
641 /* Should warn here, but modpost runs before the linker */
643 warn("\"%s\" [%s] is COMMON symbol\n", symname
, mod
->name
);
646 /* undefined symbol */
647 if (ELF_ST_BIND(sym
->st_info
) != STB_GLOBAL
&&
648 ELF_ST_BIND(sym
->st_info
) != STB_WEAK
)
650 if (ignore_undef_symbol(info
, symname
))
652 /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
653 #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
654 /* add compatibility with older glibc */
655 #ifndef STT_SPARC_REGISTER
656 #define STT_SPARC_REGISTER STT_REGISTER
658 if (info
->hdr
->e_machine
== EM_SPARC
||
659 info
->hdr
->e_machine
== EM_SPARCV9
) {
660 /* Ignore register directives. */
661 if (ELF_ST_TYPE(sym
->st_info
) == STT_SPARC_REGISTER
)
663 if (symname
[0] == '.') {
664 char *munged
= strdup(symname
);
666 munged
[1] = toupper(munged
[1]);
672 #ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
673 if (symname
[0] != '_')
679 const char *e
= is_vmlinux(mod
->name
) ?"":".ko";
680 warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n", symname
+ strlen(CRC_PFX
), mod
->name
, e
);
682 mod
->unres
= alloc_symbol(symname
,
683 ELF_ST_BIND(sym
->st_info
) == STB_WEAK
,
687 /* All exported symbols */
688 if (strncmp(symname
, KSYMTAB_PFX
, strlen(KSYMTAB_PFX
)) == 0) {
689 sym_add_exported(symname
+ strlen(KSYMTAB_PFX
), mod
,
692 if (strcmp(symname
, VMLINUX_SYMBOL_STR(init_module
)) == 0)
694 if (strcmp(symname
, VMLINUX_SYMBOL_STR(cleanup_module
)) == 0)
695 mod
->has_cleanup
= 1;
701 * Parse tag=value strings from .modinfo section
703 static char *next_string(char *string
, unsigned long *secsize
)
705 /* Skip non-zero chars */
708 if ((*secsize
)-- <= 1)
712 /* Skip any zero padding. */
715 if ((*secsize
)-- <= 1)
721 static char *get_next_modinfo(void *modinfo
, unsigned long modinfo_len
,
722 const char *tag
, char *info
)
725 unsigned int taglen
= strlen(tag
);
726 unsigned long size
= modinfo_len
;
729 size
-= info
- (char *)modinfo
;
730 modinfo
= next_string(info
, &size
);
733 for (p
= modinfo
; p
; p
= next_string(p
, &size
)) {
734 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
735 return p
+ taglen
+ 1;
740 static char *get_modinfo(void *modinfo
, unsigned long modinfo_len
,
744 return get_next_modinfo(modinfo
, modinfo_len
, tag
, NULL
);
748 * Test if string s ends in string sub
751 static int strrcmp(const char *s
, const char *sub
)
759 sublen
= strlen(sub
);
761 if ((slen
== 0) || (sublen
== 0))
767 return memcmp(s
+ slen
- sublen
, sub
, sublen
);
770 static const char *sym_name(struct elf_info
*elf
, Elf_Sym
*sym
)
773 return elf
->strtab
+ sym
->st_name
;
778 static const char *sec_name(struct elf_info
*elf
, int secindex
)
780 Elf_Shdr
*sechdrs
= elf
->sechdrs
;
781 return (void *)elf
->hdr
+
782 elf
->sechdrs
[elf
->secindex_strings
].sh_offset
+
783 sechdrs
[secindex
].sh_name
;
786 static const char *sech_name(struct elf_info
*elf
, Elf_Shdr
*sechdr
)
788 return (void *)elf
->hdr
+
789 elf
->sechdrs
[elf
->secindex_strings
].sh_offset
+
793 /* The pattern is an array of simple patterns.
794 * "foo" will match an exact string equal to "foo"
795 * "*foo" will match a string that ends with "foo"
796 * "foo*" will match a string that begins with "foo"
797 * "*foo*" will match a string that contains "foo"
799 static int match(const char *sym
, const char * const pat
[])
804 const char *endp
= p
+ strlen(p
) - 1;
807 if (*p
== '*' && *endp
== '*') {
808 char *here
, *bare
= strndup(p
+ 1, strlen(p
) - 2);
810 here
= strstr(sym
, bare
);
816 else if (*p
== '*') {
817 if (strrcmp(sym
, p
+ 1) == 0)
821 else if (*endp
== '*') {
822 if (strncmp(sym
, p
, strlen(p
) - 1) == 0)
827 if (strcmp(p
, sym
) == 0)
835 /* sections that we do not want to do full section mismatch check on */
836 static const char *const section_white_list
[] =
840 ".cranges", /* sh64 */
841 ".zdebug*", /* Compressed debug sections. */
842 ".GCC-command-line", /* mn10300 */
843 ".GCC.command.line", /* record-gcc-switches, non mn10300 */
844 ".mdebug*", /* alpha, score, mips etc. */
845 ".pdr", /* alpha, score, mips etc. */
850 ".xt.prop", /* xtensa */
851 ".xt.lit", /* xtensa */
852 ".arcextmap*", /* arc */
853 ".gnu.linkonce.arcext*", /* arc : modules */
854 ".cmem*", /* EZchip */
855 ".fmt_slot*", /* EZchip */
861 * This is used to find sections missing the SHF_ALLOC flag.
862 * The cause of this is often a section specified in assembler
863 * without "ax" / "aw".
865 static void check_section(const char *modname
, struct elf_info
*elf
,
868 const char *sec
= sech_name(elf
, sechdr
);
870 if (sechdr
->sh_type
== SHT_PROGBITS
&&
871 !(sechdr
->sh_flags
& SHF_ALLOC
) &&
872 !match(sec
, section_white_list
)) {
873 warn("%s (%s): unexpected non-allocatable section.\n"
874 "Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
875 "Note that for example <linux/init.h> contains\n"
876 "section definitions for use in .S files.\n\n",
883 #define ALL_INIT_DATA_SECTIONS \
884 ".init.setup", ".init.rodata", ".meminit.rodata", \
885 ".init.data", ".meminit.data"
886 #define ALL_EXIT_DATA_SECTIONS \
887 ".exit.data", ".memexit.data"
889 #define ALL_INIT_TEXT_SECTIONS \
890 ".init.text", ".meminit.text"
891 #define ALL_EXIT_TEXT_SECTIONS \
892 ".exit.text", ".memexit.text"
894 #define ALL_PCI_INIT_SECTIONS \
895 ".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \
896 ".pci_fixup_enable", ".pci_fixup_resume", \
897 ".pci_fixup_resume_early", ".pci_fixup_suspend"
899 #define ALL_XXXINIT_SECTIONS MEM_INIT_SECTIONS
900 #define ALL_XXXEXIT_SECTIONS MEM_EXIT_SECTIONS
902 #define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
903 #define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
905 #define DATA_SECTIONS ".data", ".data.rel"
906 #define TEXT_SECTIONS ".text", ".text.unlikely", ".sched.text", \
907 ".kprobes.text", ".cpuidle.text"
908 #define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \
909 ".fixup", ".entry.text", ".exception.text", ".text.*", \
912 #define INIT_SECTIONS ".init.*"
913 #define MEM_INIT_SECTIONS ".meminit.*"
915 #define EXIT_SECTIONS ".exit.*"
916 #define MEM_EXIT_SECTIONS ".memexit.*"
918 #define ALL_TEXT_SECTIONS ALL_INIT_TEXT_SECTIONS, ALL_EXIT_TEXT_SECTIONS, \
919 TEXT_SECTIONS, OTHER_TEXT_SECTIONS
921 /* init data sections */
922 static const char *const init_data_sections
[] =
923 { ALL_INIT_DATA_SECTIONS
, NULL
};
925 /* all init sections */
926 static const char *const init_sections
[] = { ALL_INIT_SECTIONS
, NULL
};
928 /* All init and exit sections (code + data) */
929 static const char *const init_exit_sections
[] =
930 {ALL_INIT_SECTIONS
, ALL_EXIT_SECTIONS
, NULL
};
932 /* all text sections */
933 static const char *const text_sections
[] = { ALL_TEXT_SECTIONS
, NULL
};
936 static const char *const data_sections
[] = { DATA_SECTIONS
, NULL
};
939 /* symbols in .data that may refer to init/exit sections */
940 #define DEFAULT_SYMBOL_WHITE_LIST \
942 "*_template", /* scsi uses *_template a lot */ \
943 "*_timer", /* arm uses ops structures named _timer a lot */ \
944 "*_sht", /* scsi also used *_sht to some extent */ \
950 static const char *const head_sections
[] = { ".head.text*", NULL
};
951 static const char *const linker_symbols
[] =
952 { "__init_begin", "_sinittext", "_einittext", NULL
};
953 static const char *const optim_symbols
[] = { "*.constprop.*", NULL
};
960 XXXINIT_TO_SOME_INIT
,
961 XXXEXIT_TO_SOME_EXIT
,
962 ANY_INIT_TO_ANY_EXIT
,
963 ANY_EXIT_TO_ANY_INIT
,
969 * Describe how to match sections on different criterias:
971 * @fromsec: Array of sections to be matched.
973 * @bad_tosec: Relocations applied to a section in @fromsec to a section in
974 * this array is forbidden (black-list). Can be empty.
976 * @good_tosec: Relocations applied to a section in @fromsec must be
977 * targetting sections in this array (white-list). Can be empty.
979 * @mismatch: Type of mismatch.
981 * @symbol_white_list: Do not match a relocation to a symbol in this list
982 * even if it is targetting a section in @bad_to_sec.
984 * @handler: Specific handler to call when a match is found. If NULL,
985 * default_mismatch_handler() will be called.
988 struct sectioncheck
{
989 const char *fromsec
[20];
990 const char *bad_tosec
[20];
991 const char *good_tosec
[20];
992 enum mismatch mismatch
;
993 const char *symbol_white_list
[20];
994 void (*handler
)(const char *modname
, struct elf_info
*elf
,
995 const struct sectioncheck
* const mismatch
,
996 Elf_Rela
*r
, Elf_Sym
*sym
, const char *fromsec
);
1000 static void extable_mismatch_handler(const char *modname
, struct elf_info
*elf
,
1001 const struct sectioncheck
* const mismatch
,
1002 Elf_Rela
*r
, Elf_Sym
*sym
,
1003 const char *fromsec
);
1005 static const struct sectioncheck sectioncheck
[] = {
1006 /* Do not reference init/exit code/data from
1007 * normal code and data
1010 .fromsec
= { TEXT_SECTIONS
, NULL
},
1011 .bad_tosec
= { ALL_INIT_SECTIONS
, NULL
},
1012 .mismatch
= TEXT_TO_ANY_INIT
,
1013 .symbol_white_list
= { DEFAULT_SYMBOL_WHITE_LIST
, NULL
},
1016 .fromsec
= { DATA_SECTIONS
, NULL
},
1017 .bad_tosec
= { ALL_XXXINIT_SECTIONS
, NULL
},
1018 .mismatch
= DATA_TO_ANY_INIT
,
1019 .symbol_white_list
= { DEFAULT_SYMBOL_WHITE_LIST
, NULL
},
1022 .fromsec
= { DATA_SECTIONS
, NULL
},
1023 .bad_tosec
= { INIT_SECTIONS
, NULL
},
1024 .mismatch
= DATA_TO_ANY_INIT
,
1025 .symbol_white_list
= {
1026 "*_template", "*_timer", "*_sht", "*_ops",
1027 "*_probe", "*_probe_one", "*_console", NULL
1031 .fromsec
= { TEXT_SECTIONS
, NULL
},
1032 .bad_tosec
= { ALL_EXIT_SECTIONS
, NULL
},
1033 .mismatch
= TEXT_TO_ANY_EXIT
,
1034 .symbol_white_list
= { DEFAULT_SYMBOL_WHITE_LIST
, NULL
},
1037 .fromsec
= { DATA_SECTIONS
, NULL
},
1038 .bad_tosec
= { ALL_EXIT_SECTIONS
, NULL
},
1039 .mismatch
= DATA_TO_ANY_EXIT
,
1040 .symbol_white_list
= { DEFAULT_SYMBOL_WHITE_LIST
, NULL
},
1042 /* Do not reference init code/data from meminit code/data */
1044 .fromsec
= { ALL_XXXINIT_SECTIONS
, NULL
},
1045 .bad_tosec
= { INIT_SECTIONS
, NULL
},
1046 .mismatch
= XXXINIT_TO_SOME_INIT
,
1047 .symbol_white_list
= { DEFAULT_SYMBOL_WHITE_LIST
, NULL
},
1049 /* Do not reference exit code/data from memexit code/data */
1051 .fromsec
= { ALL_XXXEXIT_SECTIONS
, NULL
},
1052 .bad_tosec
= { EXIT_SECTIONS
, NULL
},
1053 .mismatch
= XXXEXIT_TO_SOME_EXIT
,
1054 .symbol_white_list
= { DEFAULT_SYMBOL_WHITE_LIST
, NULL
},
1056 /* Do not use exit code/data from init code */
1058 .fromsec
= { ALL_INIT_SECTIONS
, NULL
},
1059 .bad_tosec
= { ALL_EXIT_SECTIONS
, NULL
},
1060 .mismatch
= ANY_INIT_TO_ANY_EXIT
,
1061 .symbol_white_list
= { DEFAULT_SYMBOL_WHITE_LIST
, NULL
},
1063 /* Do not use init code/data from exit code */
1065 .fromsec
= { ALL_EXIT_SECTIONS
, NULL
},
1066 .bad_tosec
= { ALL_INIT_SECTIONS
, NULL
},
1067 .mismatch
= ANY_EXIT_TO_ANY_INIT
,
1068 .symbol_white_list
= { DEFAULT_SYMBOL_WHITE_LIST
, NULL
},
1071 .fromsec
= { ALL_PCI_INIT_SECTIONS
, NULL
},
1072 .bad_tosec
= { INIT_SECTIONS
, NULL
},
1073 .mismatch
= ANY_INIT_TO_ANY_EXIT
,
1074 .symbol_white_list
= { NULL
},
1076 /* Do not export init/exit functions or data */
1078 .fromsec
= { "__ksymtab*", NULL
},
1079 .bad_tosec
= { INIT_SECTIONS
, EXIT_SECTIONS
, NULL
},
1080 .mismatch
= EXPORT_TO_INIT_EXIT
,
1081 .symbol_white_list
= { DEFAULT_SYMBOL_WHITE_LIST
, NULL
},
1084 .fromsec
= { "__ex_table", NULL
},
1085 /* If you're adding any new black-listed sections in here, consider
1086 * adding a special 'printer' for them in scripts/check_extable.
1088 .bad_tosec
= { ".altinstr_replacement", NULL
},
1089 .good_tosec
= {ALL_TEXT_SECTIONS
, NULL
},
1090 .mismatch
= EXTABLE_TO_NON_TEXT
,
1091 .handler
= extable_mismatch_handler
,
1095 static const struct sectioncheck
*section_mismatch(
1096 const char *fromsec
, const char *tosec
)
1099 int elems
= sizeof(sectioncheck
) / sizeof(struct sectioncheck
);
1100 const struct sectioncheck
*check
= §ioncheck
[0];
1103 * The target section could be the SHT_NUL section when we're
1104 * handling relocations to un-resolved symbols, trying to match it
1105 * doesn't make much sense and causes build failures on parisc and
1106 * mn10300 architectures.
1111 for (i
= 0; i
< elems
; i
++) {
1112 if (match(fromsec
, check
->fromsec
)) {
1113 if (check
->bad_tosec
[0] && match(tosec
, check
->bad_tosec
))
1115 if (check
->good_tosec
[0] && !match(tosec
, check
->good_tosec
))
1124 * Whitelist to allow certain references to pass with no warning.
1127 * If a module parameter is declared __initdata and permissions=0
1128 * then this is legal despite the warning generated.
1129 * We cannot see value of permissions here, so just ignore
1131 * The pattern is identified by:
1132 * tosec = .init.data
1137 * module_param_call() ops can refer to __init set function if permissions=0
1138 * The pattern is identified by:
1139 * tosec = .init.text
1141 * atsym = __param_ops_*
1144 * Many drivers utilise a *driver container with references to
1145 * add, remove, probe functions etc.
1146 * the pattern is identified by:
1147 * tosec = init or exit section
1148 * fromsec = data section
1149 * atsym = *driver, *_template, *_sht, *_ops, *_probe,
1150 * *probe_one, *_console, *_timer
1153 * Whitelist all references from .head.text to any init section
1156 * Some symbols belong to init section but still it is ok to reference
1157 * these from non-init sections as these symbols don't have any memory
1158 * allocated for them and symbol address and value are same. So even
1159 * if init section is freed, its ok to reference those symbols.
1160 * For ex. symbols marking the init section boundaries.
1161 * This pattern is identified by
1162 * refsymname = __init_begin, _sinittext, _einittext
1165 * GCC may optimize static inlines when fed constant arg(s) resulting
1166 * in functions like cpumask_empty() -- generating an associated symbol
1167 * cpumask_empty.constprop.3 that appears in the audit. If the const that
1168 * is passed in comes from __init, like say nmi_ipi_mask, we get a
1169 * meaningless section warning. May need to add isra symbols too...
1170 * This pattern is identified by
1171 * tosec = init section
1172 * fromsec = text section
1173 * refsymname = *.constprop.*
1176 static int secref_whitelist(const struct sectioncheck
*mismatch
,
1177 const char *fromsec
, const char *fromsym
,
1178 const char *tosec
, const char *tosym
)
1180 /* Check for pattern 1 */
1181 if (match(tosec
, init_data_sections
) &&
1182 match(fromsec
, data_sections
) &&
1183 (strncmp(fromsym
, "__param", strlen("__param")) == 0))
1186 /* Check for pattern 1a */
1187 if (strcmp(tosec
, ".init.text") == 0 &&
1188 match(fromsec
, data_sections
) &&
1189 (strncmp(fromsym
, "__param_ops_", strlen("__param_ops_")) == 0))
1192 /* Check for pattern 2 */
1193 if (match(tosec
, init_exit_sections
) &&
1194 match(fromsec
, data_sections
) &&
1195 match(fromsym
, mismatch
->symbol_white_list
))
1198 /* Check for pattern 3 */
1199 if (match(fromsec
, head_sections
) &&
1200 match(tosec
, init_sections
))
1203 /* Check for pattern 4 */
1204 if (match(tosym
, linker_symbols
))
1207 /* Check for pattern 5 */
1208 if (match(fromsec
, text_sections
) &&
1209 match(tosec
, init_sections
) &&
1210 match(fromsym
, optim_symbols
))
1217 * Find symbol based on relocation record info.
1218 * In some cases the symbol supplied is a valid symbol so
1219 * return refsym. If st_name != 0 we assume this is a valid symbol.
1220 * In other cases the symbol needs to be looked up in the symbol table
1221 * based on section and address.
1223 static Elf_Sym
*find_elf_symbol(struct elf_info
*elf
, Elf64_Sword addr
,
1227 Elf_Sym
*near
= NULL
;
1228 Elf64_Sword distance
= 20;
1230 unsigned int relsym_secindex
;
1232 if (relsym
->st_name
!= 0)
1235 relsym_secindex
= get_secindex(elf
, relsym
);
1236 for (sym
= elf
->symtab_start
; sym
< elf
->symtab_stop
; sym
++) {
1237 if (get_secindex(elf
, sym
) != relsym_secindex
)
1239 if (ELF_ST_TYPE(sym
->st_info
) == STT_SECTION
)
1241 if (sym
->st_value
== addr
)
1243 /* Find a symbol nearby - addr are maybe negative */
1244 d
= sym
->st_value
- addr
;
1246 d
= addr
- sym
->st_value
;
1252 /* We need a close match */
1259 static inline int is_arm_mapping_symbol(const char *str
)
1261 return str
[0] == '$' && strchr("axtd", str
[1])
1262 && (str
[2] == '\0' || str
[2] == '.');
1266 * If there's no name there, ignore it; likewise, ignore it if it's
1267 * one of the magic symbols emitted used by current ARM tools.
1269 * Otherwise if find_symbols_between() returns those symbols, they'll
1270 * fail the whitelist tests and cause lots of false alarms ... fixable
1271 * only by merging __exit and __init sections into __text, bloating
1272 * the kernel (which is especially evil on embedded platforms).
1274 static inline int is_valid_name(struct elf_info
*elf
, Elf_Sym
*sym
)
1276 const char *name
= elf
->strtab
+ sym
->st_name
;
1278 if (!name
|| !strlen(name
))
1280 return !is_arm_mapping_symbol(name
);
1284 * Find symbols before or equal addr and after addr - in the section sec.
1285 * If we find two symbols with equal offset prefer one with a valid name.
1286 * The ELF format may have a better way to detect what type of symbol
1287 * it is, but this works for now.
1289 static Elf_Sym
*find_elf_symbol2(struct elf_info
*elf
, Elf_Addr addr
,
1293 Elf_Sym
*near
= NULL
;
1294 Elf_Addr distance
= ~0;
1296 for (sym
= elf
->symtab_start
; sym
< elf
->symtab_stop
; sym
++) {
1299 if (is_shndx_special(sym
->st_shndx
))
1301 symsec
= sec_name(elf
, get_secindex(elf
, sym
));
1302 if (strcmp(symsec
, sec
) != 0)
1304 if (!is_valid_name(elf
, sym
))
1306 if (sym
->st_value
<= addr
) {
1307 if ((addr
- sym
->st_value
) < distance
) {
1308 distance
= addr
- sym
->st_value
;
1310 } else if ((addr
- sym
->st_value
) == distance
) {
1319 * Convert a section name to the function/data attribute
1320 * .init.text => __init
1321 * .memexitconst => __memconst
1324 * The memory of returned value has been allocated on a heap. The user of this
1325 * method should free it after usage.
1327 static char *sec2annotation(const char *s
)
1329 if (match(s
, init_exit_sections
)) {
1330 char *p
= malloc(20);
1337 while (*s
&& *s
!= '.')
1342 if (strstr(s
, "rodata") != NULL
)
1343 strcat(p
, "const ");
1344 else if (strstr(s
, "data") != NULL
)
1354 static int is_function(Elf_Sym
*sym
)
1357 return ELF_ST_TYPE(sym
->st_info
) == STT_FUNC
;
1362 static void print_section_list(const char * const list
[20])
1364 const char *const *s
= list
;
1367 fprintf(stderr
, "%s", *s
);
1370 fprintf(stderr
, ", ");
1372 fprintf(stderr
, "\n");
1375 static inline void get_pretty_name(int is_func
, const char** name
, const char** name_p
)
1378 case 0: *name
= "variable"; *name_p
= ""; break;
1379 case 1: *name
= "function"; *name_p
= "()"; break;
1380 default: *name
= "(unknown reference)"; *name_p
= ""; break;
1385 * Print a warning about a section mismatch.
1386 * Try to find symbols near it so user can find it.
1387 * Check whitelist before warning - it may be a false positive.
1389 static void report_sec_mismatch(const char *modname
,
1390 const struct sectioncheck
*mismatch
,
1391 const char *fromsec
,
1392 unsigned long long fromaddr
,
1393 const char *fromsym
,
1395 const char *tosec
, const char *tosym
,
1398 const char *from
, *from_p
;
1399 const char *to
, *to_p
;
1403 sec_mismatch_count
++;
1404 if (!sec_mismatch_verbose
)
1407 get_pretty_name(from_is_func
, &from
, &from_p
);
1408 get_pretty_name(to_is_func
, &to
, &to_p
);
1410 warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
1411 "to the %s %s:%s%s\n",
1412 modname
, fromsec
, fromaddr
, from
, fromsym
, from_p
, to
, tosec
,
1415 switch (mismatch
->mismatch
) {
1416 case TEXT_TO_ANY_INIT
:
1417 prl_from
= sec2annotation(fromsec
);
1418 prl_to
= sec2annotation(tosec
);
1420 "The function %s%s() references\n"
1422 "This is often because %s lacks a %s\n"
1423 "annotation or the annotation of %s is wrong.\n",
1425 to
, prl_to
, tosym
, to_p
,
1426 fromsym
, prl_to
, tosym
);
1430 case DATA_TO_ANY_INIT
: {
1431 prl_to
= sec2annotation(tosec
);
1433 "The variable %s references\n"
1435 "If the reference is valid then annotate the\n"
1436 "variable with __init* or __refdata (see linux/init.h) "
1437 "or name the variable:\n",
1438 fromsym
, to
, prl_to
, tosym
, to_p
);
1439 print_section_list(mismatch
->symbol_white_list
);
1443 case TEXT_TO_ANY_EXIT
:
1444 prl_to
= sec2annotation(tosec
);
1446 "The function %s() references a %s in an exit section.\n"
1447 "Often the %s %s%s has valid usage outside the exit section\n"
1448 "and the fix is to remove the %sannotation of %s.\n",
1449 fromsym
, to
, to
, tosym
, to_p
, prl_to
, tosym
);
1452 case DATA_TO_ANY_EXIT
: {
1453 prl_to
= sec2annotation(tosec
);
1455 "The variable %s references\n"
1457 "If the reference is valid then annotate the\n"
1458 "variable with __exit* (see linux/init.h) or "
1459 "name the variable:\n",
1460 fromsym
, to
, prl_to
, tosym
, to_p
);
1461 print_section_list(mismatch
->symbol_white_list
);
1465 case XXXINIT_TO_SOME_INIT
:
1466 case XXXEXIT_TO_SOME_EXIT
:
1467 prl_from
= sec2annotation(fromsec
);
1468 prl_to
= sec2annotation(tosec
);
1470 "The %s %s%s%s references\n"
1472 "If %s is only used by %s then\n"
1473 "annotate %s with a matching annotation.\n",
1474 from
, prl_from
, fromsym
, from_p
,
1475 to
, prl_to
, tosym
, to_p
,
1476 tosym
, fromsym
, tosym
);
1480 case ANY_INIT_TO_ANY_EXIT
:
1481 prl_from
= sec2annotation(fromsec
);
1482 prl_to
= sec2annotation(tosec
);
1484 "The %s %s%s%s references\n"
1486 "This is often seen when error handling "
1487 "in the init function\n"
1488 "uses functionality in the exit path.\n"
1489 "The fix is often to remove the %sannotation of\n"
1490 "%s%s so it may be used outside an exit section.\n",
1491 from
, prl_from
, fromsym
, from_p
,
1492 to
, prl_to
, tosym
, to_p
,
1493 prl_to
, tosym
, to_p
);
1497 case ANY_EXIT_TO_ANY_INIT
:
1498 prl_from
= sec2annotation(fromsec
);
1499 prl_to
= sec2annotation(tosec
);
1501 "The %s %s%s%s references\n"
1503 "This is often seen when error handling "
1504 "in the exit function\n"
1505 "uses functionality in the init path.\n"
1506 "The fix is often to remove the %sannotation of\n"
1507 "%s%s so it may be used outside an init section.\n",
1508 from
, prl_from
, fromsym
, from_p
,
1509 to
, prl_to
, tosym
, to_p
,
1510 prl_to
, tosym
, to_p
);
1514 case EXPORT_TO_INIT_EXIT
:
1515 prl_to
= sec2annotation(tosec
);
1517 "The symbol %s is exported and annotated %s\n"
1518 "Fix this by removing the %sannotation of %s "
1519 "or drop the export.\n",
1520 tosym
, prl_to
, prl_to
, tosym
);
1523 case EXTABLE_TO_NON_TEXT
:
1524 fatal("There's a special handler for this mismatch type, "
1525 "we should never get here.");
1528 fprintf(stderr
, "\n");
1531 static void default_mismatch_handler(const char *modname
, struct elf_info
*elf
,
1532 const struct sectioncheck
* const mismatch
,
1533 Elf_Rela
*r
, Elf_Sym
*sym
, const char *fromsec
)
1539 const char *fromsym
;
1541 from
= find_elf_symbol2(elf
, r
->r_offset
, fromsec
);
1542 fromsym
= sym_name(elf
, from
);
1544 if (!strncmp(fromsym
, "reference___initcall",
1545 sizeof("reference___initcall")-1))
1548 tosec
= sec_name(elf
, get_secindex(elf
, sym
));
1549 to
= find_elf_symbol(elf
, r
->r_addend
, sym
);
1550 tosym
= sym_name(elf
, to
);
1552 /* check whitelist - we may ignore it */
1553 if (secref_whitelist(mismatch
,
1554 fromsec
, fromsym
, tosec
, tosym
)) {
1555 report_sec_mismatch(modname
, mismatch
,
1556 fromsec
, r
->r_offset
, fromsym
,
1557 is_function(from
), tosec
, tosym
,
1562 static int is_executable_section(struct elf_info
* elf
, unsigned int section_index
)
1564 if (section_index
> elf
->num_sections
)
1565 fatal("section_index is outside elf->num_sections!\n");
1567 return ((elf
->sechdrs
[section_index
].sh_flags
& SHF_EXECINSTR
) == SHF_EXECINSTR
);
1571 * We rely on a gross hack in section_rel[a]() calling find_extable_entry_size()
1572 * to know the sizeof(struct exception_table_entry) for the target architecture.
1574 static unsigned int extable_entry_size
= 0;
1575 static void find_extable_entry_size(const char* const sec
, const Elf_Rela
* r
)
1578 * If we're currently checking the second relocation within __ex_table,
1579 * that relocation offset tells us the offsetof(struct
1580 * exception_table_entry, fixup) which is equal to sizeof(struct
1581 * exception_table_entry) divided by two. We use that to our advantage
1582 * since there's no portable way to get that size as every architecture
1583 * seems to go with different sized types. Not pretty but better than
1584 * hard-coding the size for every architecture..
1586 if (!extable_entry_size
)
1587 extable_entry_size
= r
->r_offset
* 2;
1590 static inline bool is_extable_fault_address(Elf_Rela
*r
)
1593 * extable_entry_size is only discovered after we've handled the
1594 * _second_ relocation in __ex_table, so only abort when we're not
1595 * handling the first reloc and extable_entry_size is zero.
1597 if (r
->r_offset
&& extable_entry_size
== 0)
1598 fatal("extable_entry size hasn't been discovered!\n");
1600 return ((r
->r_offset
== 0) ||
1601 (r
->r_offset
% extable_entry_size
== 0));
1604 #define is_second_extable_reloc(Start, Cur, Sec) \
1605 (((Cur) == (Start) + 1) && (strcmp("__ex_table", (Sec)) == 0))
1607 static void report_extable_warnings(const char* modname
, struct elf_info
* elf
,
1608 const struct sectioncheck
* const mismatch
,
1609 Elf_Rela
* r
, Elf_Sym
* sym
,
1610 const char* fromsec
, const char* tosec
)
1612 Elf_Sym
* fromsym
= find_elf_symbol2(elf
, r
->r_offset
, fromsec
);
1613 const char* fromsym_name
= sym_name(elf
, fromsym
);
1614 Elf_Sym
* tosym
= find_elf_symbol(elf
, r
->r_addend
, sym
);
1615 const char* tosym_name
= sym_name(elf
, tosym
);
1616 const char* from_pretty_name
;
1617 const char* from_pretty_name_p
;
1618 const char* to_pretty_name
;
1619 const char* to_pretty_name_p
;
1621 get_pretty_name(is_function(fromsym
),
1622 &from_pretty_name
, &from_pretty_name_p
);
1623 get_pretty_name(is_function(tosym
),
1624 &to_pretty_name
, &to_pretty_name_p
);
1626 warn("%s(%s+0x%lx): Section mismatch in reference"
1627 " from the %s %s%s to the %s %s:%s%s\n",
1628 modname
, fromsec
, (long)r
->r_offset
, from_pretty_name
,
1629 fromsym_name
, from_pretty_name_p
,
1630 to_pretty_name
, tosec
, tosym_name
, to_pretty_name_p
);
1632 if (!match(tosec
, mismatch
->bad_tosec
) &&
1633 is_executable_section(elf
, get_secindex(elf
, sym
)))
1635 "The relocation at %s+0x%lx references\n"
1636 "section \"%s\" which is not in the list of\n"
1637 "authorized sections. If you're adding a new section\n"
1638 "and/or if this reference is valid, add \"%s\" to the\n"
1639 "list of authorized sections to jump to on fault.\n"
1640 "This can be achieved by adding \"%s\" to \n"
1641 "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n",
1642 fromsec
, (long)r
->r_offset
, tosec
, tosec
, tosec
);
1645 static void extable_mismatch_handler(const char* modname
, struct elf_info
*elf
,
1646 const struct sectioncheck
* const mismatch
,
1647 Elf_Rela
* r
, Elf_Sym
* sym
,
1648 const char *fromsec
)
1650 const char* tosec
= sec_name(elf
, get_secindex(elf
, sym
));
1652 sec_mismatch_count
++;
1654 if (sec_mismatch_verbose
)
1655 report_extable_warnings(modname
, elf
, mismatch
, r
, sym
,
1658 if (match(tosec
, mismatch
->bad_tosec
))
1659 fatal("The relocation at %s+0x%lx references\n"
1660 "section \"%s\" which is black-listed.\n"
1661 "Something is seriously wrong and should be fixed.\n"
1662 "You might get more information about where this is\n"
1663 "coming from by using scripts/check_extable.sh %s\n",
1664 fromsec
, (long)r
->r_offset
, tosec
, modname
);
1665 else if (!is_executable_section(elf
, get_secindex(elf
, sym
))) {
1666 if (is_extable_fault_address(r
))
1667 fatal("The relocation at %s+0x%lx references\n"
1668 "section \"%s\" which is not executable, IOW\n"
1669 "it is not possible for the kernel to fault\n"
1670 "at that address. Something is seriously wrong\n"
1671 "and should be fixed.\n",
1672 fromsec
, (long)r
->r_offset
, tosec
);
1674 fatal("The relocation at %s+0x%lx references\n"
1675 "section \"%s\" which is not executable, IOW\n"
1676 "the kernel will fault if it ever tries to\n"
1677 "jump to it. Something is seriously wrong\n"
1678 "and should be fixed.\n",
1679 fromsec
, (long)r
->r_offset
, tosec
);
1683 static void check_section_mismatch(const char *modname
, struct elf_info
*elf
,
1684 Elf_Rela
*r
, Elf_Sym
*sym
, const char *fromsec
)
1686 const char *tosec
= sec_name(elf
, get_secindex(elf
, sym
));;
1687 const struct sectioncheck
*mismatch
= section_mismatch(fromsec
, tosec
);
1690 if (mismatch
->handler
)
1691 mismatch
->handler(modname
, elf
, mismatch
,
1694 default_mismatch_handler(modname
, elf
, mismatch
,
1699 static unsigned int *reloc_location(struct elf_info
*elf
,
1700 Elf_Shdr
*sechdr
, Elf_Rela
*r
)
1702 Elf_Shdr
*sechdrs
= elf
->sechdrs
;
1703 int section
= sechdr
->sh_info
;
1705 return (void *)elf
->hdr
+ sechdrs
[section
].sh_offset
+
1709 static int addend_386_rel(struct elf_info
*elf
, Elf_Shdr
*sechdr
, Elf_Rela
*r
)
1711 unsigned int r_typ
= ELF_R_TYPE(r
->r_info
);
1712 unsigned int *location
= reloc_location(elf
, sechdr
, r
);
1716 r
->r_addend
= TO_NATIVE(*location
);
1719 r
->r_addend
= TO_NATIVE(*location
) + 4;
1720 /* For CONFIG_RELOCATABLE=y */
1721 if (elf
->hdr
->e_type
== ET_EXEC
)
1722 r
->r_addend
+= r
->r_offset
;
1729 #define R_ARM_CALL 28
1731 #ifndef R_ARM_JUMP24
1732 #define R_ARM_JUMP24 29
1735 #ifndef R_ARM_THM_CALL
1736 #define R_ARM_THM_CALL 10
1738 #ifndef R_ARM_THM_JUMP24
1739 #define R_ARM_THM_JUMP24 30
1741 #ifndef R_ARM_THM_JUMP19
1742 #define R_ARM_THM_JUMP19 51
1745 static int addend_arm_rel(struct elf_info
*elf
, Elf_Shdr
*sechdr
, Elf_Rela
*r
)
1747 unsigned int r_typ
= ELF_R_TYPE(r
->r_info
);
1751 /* From ARM ABI: (S + A) | T */
1752 r
->r_addend
= (int)(long)
1753 (elf
->symtab_start
+ ELF_R_SYM(r
->r_info
));
1758 case R_ARM_THM_CALL
:
1759 case R_ARM_THM_JUMP24
:
1760 case R_ARM_THM_JUMP19
:
1761 /* From ARM ABI: ((S + A) | T) - P */
1762 r
->r_addend
= (int)(long)(elf
->hdr
+
1764 (r
->r_offset
- sechdr
->sh_addr
));
1772 static int addend_mips_rel(struct elf_info
*elf
, Elf_Shdr
*sechdr
, Elf_Rela
*r
)
1774 unsigned int r_typ
= ELF_R_TYPE(r
->r_info
);
1775 unsigned int *location
= reloc_location(elf
, sechdr
, r
);
1778 if (r_typ
== R_MIPS_HI16
)
1779 return 1; /* skip this */
1780 inst
= TO_NATIVE(*location
);
1783 r
->r_addend
= inst
& 0xffff;
1786 r
->r_addend
= (inst
& 0x03ffffff) << 2;
1795 static void section_rela(const char *modname
, struct elf_info
*elf
,
1802 const char *fromsec
;
1804 Elf_Rela
*start
= (void *)elf
->hdr
+ sechdr
->sh_offset
;
1805 Elf_Rela
*stop
= (void *)start
+ sechdr
->sh_size
;
1807 fromsec
= sech_name(elf
, sechdr
);
1808 fromsec
+= strlen(".rela");
1809 /* if from section (name) is know good then skip it */
1810 if (match(fromsec
, section_white_list
))
1813 for (rela
= start
; rela
< stop
; rela
++) {
1814 r
.r_offset
= TO_NATIVE(rela
->r_offset
);
1815 #if KERNEL_ELFCLASS == ELFCLASS64
1816 if (elf
->hdr
->e_machine
== EM_MIPS
) {
1818 r_sym
= ELF64_MIPS_R_SYM(rela
->r_info
);
1819 r_sym
= TO_NATIVE(r_sym
);
1820 r_typ
= ELF64_MIPS_R_TYPE(rela
->r_info
);
1821 r
.r_info
= ELF64_R_INFO(r_sym
, r_typ
);
1823 r
.r_info
= TO_NATIVE(rela
->r_info
);
1824 r_sym
= ELF_R_SYM(r
.r_info
);
1827 r
.r_info
= TO_NATIVE(rela
->r_info
);
1828 r_sym
= ELF_R_SYM(r
.r_info
);
1830 r
.r_addend
= TO_NATIVE(rela
->r_addend
);
1831 sym
= elf
->symtab_start
+ r_sym
;
1832 /* Skip special sections */
1833 if (is_shndx_special(sym
->st_shndx
))
1835 if (is_second_extable_reloc(start
, rela
, fromsec
))
1836 find_extable_entry_size(fromsec
, &r
);
1837 check_section_mismatch(modname
, elf
, &r
, sym
, fromsec
);
1841 static void section_rel(const char *modname
, struct elf_info
*elf
,
1848 const char *fromsec
;
1850 Elf_Rel
*start
= (void *)elf
->hdr
+ sechdr
->sh_offset
;
1851 Elf_Rel
*stop
= (void *)start
+ sechdr
->sh_size
;
1853 fromsec
= sech_name(elf
, sechdr
);
1854 fromsec
+= strlen(".rel");
1855 /* if from section (name) is know good then skip it */
1856 if (match(fromsec
, section_white_list
))
1859 for (rel
= start
; rel
< stop
; rel
++) {
1860 r
.r_offset
= TO_NATIVE(rel
->r_offset
);
1861 #if KERNEL_ELFCLASS == ELFCLASS64
1862 if (elf
->hdr
->e_machine
== EM_MIPS
) {
1864 r_sym
= ELF64_MIPS_R_SYM(rel
->r_info
);
1865 r_sym
= TO_NATIVE(r_sym
);
1866 r_typ
= ELF64_MIPS_R_TYPE(rel
->r_info
);
1867 r
.r_info
= ELF64_R_INFO(r_sym
, r_typ
);
1869 r
.r_info
= TO_NATIVE(rel
->r_info
);
1870 r_sym
= ELF_R_SYM(r
.r_info
);
1873 r
.r_info
= TO_NATIVE(rel
->r_info
);
1874 r_sym
= ELF_R_SYM(r
.r_info
);
1877 switch (elf
->hdr
->e_machine
) {
1879 if (addend_386_rel(elf
, sechdr
, &r
))
1883 if (addend_arm_rel(elf
, sechdr
, &r
))
1887 if (addend_mips_rel(elf
, sechdr
, &r
))
1891 sym
= elf
->symtab_start
+ r_sym
;
1892 /* Skip special sections */
1893 if (is_shndx_special(sym
->st_shndx
))
1895 if (is_second_extable_reloc(start
, rel
, fromsec
))
1896 find_extable_entry_size(fromsec
, &r
);
1897 check_section_mismatch(modname
, elf
, &r
, sym
, fromsec
);
1902 * A module includes a number of sections that are discarded
1903 * either when loaded or when used as built-in.
1904 * For loaded modules all functions marked __init and all data
1905 * marked __initdata will be discarded when the module has been initialized.
1906 * Likewise for modules used built-in the sections marked __exit
1907 * are discarded because __exit marked function are supposed to be called
1908 * only when a module is unloaded which never happens for built-in modules.
1909 * The check_sec_ref() function traverses all relocation records
1910 * to find all references to a section that reference a section that will
1911 * be discarded and warns about it.
1913 static void check_sec_ref(struct module
*mod
, const char *modname
,
1914 struct elf_info
*elf
)
1917 Elf_Shdr
*sechdrs
= elf
->sechdrs
;
1919 /* Walk through all sections */
1920 for (i
= 0; i
< elf
->num_sections
; i
++) {
1921 check_section(modname
, elf
, &elf
->sechdrs
[i
]);
1922 /* We want to process only relocation sections and not .init */
1923 if (sechdrs
[i
].sh_type
== SHT_RELA
)
1924 section_rela(modname
, elf
, &elf
->sechdrs
[i
]);
1925 else if (sechdrs
[i
].sh_type
== SHT_REL
)
1926 section_rel(modname
, elf
, &elf
->sechdrs
[i
]);
1930 static char *remove_dot(char *s
)
1932 size_t n
= strcspn(s
, ".");
1935 size_t m
= strspn(s
+ n
+ 1, "0123456789");
1936 if (m
&& (s
[n
+ m
] == '.' || s
[n
+ m
] == 0))
1942 static void read_symbols(char *modname
)
1944 const char *symname
;
1948 struct elf_info info
= { };
1951 if (!parse_elf(&info
, modname
))
1954 mod
= new_module(modname
);
1956 /* When there's no vmlinux, don't print warnings about
1957 * unresolved symbols (since there'll be too many ;) */
1958 if (is_vmlinux(modname
)) {
1963 license
= get_modinfo(info
.modinfo
, info
.modinfo_len
, "license");
1964 if (info
.modinfo
&& !license
&& !is_vmlinux(modname
))
1965 warn("modpost: missing MODULE_LICENSE() in %s\n"
1966 "see include/linux/module.h for "
1967 "more information\n", modname
);
1969 if (license_is_gpl_compatible(license
))
1970 mod
->gpl_compatible
= 1;
1972 mod
->gpl_compatible
= 0;
1975 license
= get_next_modinfo(info
.modinfo
, info
.modinfo_len
,
1976 "license", license
);
1979 for (sym
= info
.symtab_start
; sym
< info
.symtab_stop
; sym
++) {
1980 symname
= remove_dot(info
.strtab
+ sym
->st_name
);
1982 handle_modversions(mod
, &info
, sym
, symname
);
1983 handle_moddevtable(mod
, &info
, sym
, symname
);
1985 if (!is_vmlinux(modname
) ||
1986 (is_vmlinux(modname
) && vmlinux_section_warnings
))
1987 check_sec_ref(mod
, modname
, &info
);
1989 version
= get_modinfo(info
.modinfo
, info
.modinfo_len
, "version");
1991 maybe_frob_rcs_version(modname
, version
, info
.modinfo
,
1992 version
- (char *)info
.hdr
);
1993 if (version
|| (all_versions
&& !is_vmlinux(modname
)))
1994 get_src_version(modname
, mod
->srcversion
,
1995 sizeof(mod
->srcversion
)-1);
1997 parse_elf_finish(&info
);
1999 /* Our trick to get versioning for module struct etc. - it's
2000 * never passed as an argument to an exported function, so
2001 * the automatic versioning doesn't pick it up, but it's really
2002 * important anyhow */
2004 mod
->unres
= alloc_symbol("module_layout", 0, mod
->unres
);
2007 static void read_symbols_from_files(const char *filename
)
2010 char fname
[PATH_MAX
];
2012 if (strcmp(filename
, "-") != 0) {
2013 in
= fopen(filename
, "r");
2015 fatal("Can't open filenames file %s: %m", filename
);
2018 while (fgets(fname
, PATH_MAX
, in
) != NULL
) {
2019 if (strends(fname
, "\n"))
2020 fname
[strlen(fname
)-1] = '\0';
2021 read_symbols(fname
);
2030 /* We first write the generated file into memory using the
2031 * following helper, then compare to the file on disk and
2032 * only update the later if anything changed */
2034 void __attribute__((format(printf
, 2, 3))) buf_printf(struct buffer
*buf
,
2035 const char *fmt
, ...)
2042 len
= vsnprintf(tmp
, SZ
, fmt
, ap
);
2043 buf_write(buf
, tmp
, len
);
2047 void buf_write(struct buffer
*buf
, const char *s
, int len
)
2049 if (buf
->size
- buf
->pos
< len
) {
2050 buf
->size
+= len
+ SZ
;
2051 buf
->p
= realloc(buf
->p
, buf
->size
);
2053 strncpy(buf
->p
+ buf
->pos
, s
, len
);
2057 static void check_for_gpl_usage(enum export exp
, const char *m
, const char *s
)
2059 const char *e
= is_vmlinux(m
) ?"":".ko";
2063 fatal("modpost: GPL-incompatible module %s%s "
2064 "uses GPL-only symbol '%s'\n", m
, e
, s
);
2066 case export_unused_gpl
:
2067 fatal("modpost: GPL-incompatible module %s%s "
2068 "uses GPL-only symbol marked UNUSED '%s'\n", m
, e
, s
);
2070 case export_gpl_future
:
2071 warn("modpost: GPL-incompatible module %s%s "
2072 "uses future GPL-only symbol '%s'\n", m
, e
, s
);
2076 case export_unknown
:
2082 static void check_for_unused(enum export exp
, const char *m
, const char *s
)
2084 const char *e
= is_vmlinux(m
) ?"":".ko";
2088 case export_unused_gpl
:
2089 warn("modpost: module %s%s "
2090 "uses symbol '%s' marked UNUSED\n", m
, e
, s
);
2098 static void check_exports(struct module
*mod
)
2100 struct symbol
*s
, *exp
;
2102 for (s
= mod
->unres
; s
; s
= s
->next
) {
2103 const char *basename
;
2104 exp
= find_symbol(s
->name
);
2105 if (!exp
|| exp
->module
== mod
)
2107 basename
= strrchr(mod
->name
, '/');
2111 basename
= mod
->name
;
2112 if (!mod
->gpl_compatible
)
2113 check_for_gpl_usage(exp
->export
, basename
, exp
->name
);
2114 check_for_unused(exp
->export
, basename
, exp
->name
);
2119 * Header for the generated file
2121 static void add_header(struct buffer
*b
, struct module
*mod
)
2123 buf_printf(b
, "#include <linux/module.h>\n");
2124 buf_printf(b
, "#include <linux/vermagic.h>\n");
2125 buf_printf(b
, "#include <linux/compiler.h>\n");
2126 buf_printf(b
, "\n");
2127 buf_printf(b
, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
2128 buf_printf(b
, "\n");
2129 buf_printf(b
, "__visible struct module __this_module\n");
2130 buf_printf(b
, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
2131 buf_printf(b
, "\t.name = KBUILD_MODNAME,\n");
2133 buf_printf(b
, "\t.init = init_module,\n");
2134 if (mod
->has_cleanup
)
2135 buf_printf(b
, "#ifdef CONFIG_MODULE_UNLOAD\n"
2136 "\t.exit = cleanup_module,\n"
2138 buf_printf(b
, "\t.arch = MODULE_ARCH_INIT,\n");
2139 buf_printf(b
, "};\n");
2142 static void add_intree_flag(struct buffer
*b
, int is_intree
)
2145 buf_printf(b
, "\nMODULE_INFO(intree, \"Y\");\n");
2148 static void add_staging_flag(struct buffer
*b
, const char *name
)
2150 static const char *staging_dir
= "drivers/staging";
2152 if (strncmp(staging_dir
, name
, strlen(staging_dir
)) == 0)
2153 buf_printf(b
, "\nMODULE_INFO(staging, \"Y\");\n");
2156 /* In kernel, this size is defined in linux/module.h;
2157 * here we use Elf_Addr instead of long for covering cross-compile
2159 #define MODULE_NAME_LEN (64 - sizeof(Elf_Addr))
2162 * Record CRCs for unresolved symbols
2164 static int add_versions(struct buffer
*b
, struct module
*mod
)
2166 struct symbol
*s
, *exp
;
2169 for (s
= mod
->unres
; s
; s
= s
->next
) {
2170 exp
= find_symbol(s
->name
);
2171 if (!exp
|| exp
->module
== mod
) {
2172 if (have_vmlinux
&& !s
->weak
) {
2173 if (warn_unresolved
) {
2174 warn("\"%s\" [%s.ko] undefined!\n",
2175 s
->name
, mod
->name
);
2177 merror("\"%s\" [%s.ko] undefined!\n",
2178 s
->name
, mod
->name
);
2184 s
->module
= exp
->module
;
2185 s
->crc_valid
= exp
->crc_valid
;
2192 buf_printf(b
, "\n");
2193 buf_printf(b
, "static const struct modversion_info ____versions[]\n");
2194 buf_printf(b
, "__used\n");
2195 buf_printf(b
, "__attribute__((section(\"__versions\"))) = {\n");
2197 for (s
= mod
->unres
; s
; s
= s
->next
) {
2200 if (!s
->crc_valid
) {
2201 warn("\"%s\" [%s.ko] has no CRC!\n",
2202 s
->name
, mod
->name
);
2205 if (strlen(s
->name
) >= MODULE_NAME_LEN
) {
2206 merror("too long symbol \"%s\" [%s.ko]\n",
2207 s
->name
, mod
->name
);
2211 buf_printf(b
, "\t{ %#8x, __VMLINUX_SYMBOL_STR(%s) },\n",
2215 buf_printf(b
, "};\n");
2220 static void add_depends(struct buffer
*b
, struct module
*mod
,
2221 struct module
*modules
)
2227 for (m
= modules
; m
; m
= m
->next
)
2228 m
->seen
= is_vmlinux(m
->name
);
2230 buf_printf(b
, "\n");
2231 buf_printf(b
, "static const char __module_depends[]\n");
2232 buf_printf(b
, "__used\n");
2233 buf_printf(b
, "__attribute__((section(\".modinfo\"))) =\n");
2234 buf_printf(b
, "\"depends=");
2235 for (s
= mod
->unres
; s
; s
= s
->next
) {
2240 if (s
->module
->seen
)
2243 s
->module
->seen
= 1;
2244 p
= strrchr(s
->module
->name
, '/');
2248 p
= s
->module
->name
;
2249 buf_printf(b
, "%s%s", first
? "" : ",", p
);
2252 buf_printf(b
, "\";\n");
2255 static void add_srcversion(struct buffer
*b
, struct module
*mod
)
2257 if (mod
->srcversion
[0]) {
2258 buf_printf(b
, "\n");
2259 buf_printf(b
, "MODULE_INFO(srcversion, \"%s\");\n",
2264 static void write_if_changed(struct buffer
*b
, const char *fname
)
2270 file
= fopen(fname
, "r");
2274 if (fstat(fileno(file
), &st
) < 0)
2277 if (st
.st_size
!= b
->pos
)
2280 tmp
= NOFAIL(malloc(b
->pos
));
2281 if (fread(tmp
, 1, b
->pos
, file
) != b
->pos
)
2284 if (memcmp(tmp
, b
->p
, b
->pos
) != 0)
2296 file
= fopen(fname
, "w");
2301 if (fwrite(b
->p
, 1, b
->pos
, file
) != b
->pos
) {
2308 /* parse Module.symvers file. line format:
2309 * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
2311 static void read_dump(const char *fname
, unsigned int kernel
)
2313 unsigned long size
, pos
= 0;
2314 void *file
= grab_file(fname
, &size
);
2318 /* No symbol versions, silently ignore */
2321 while ((line
= get_next_line(&pos
, file
, size
))) {
2322 char *symname
, *modname
, *d
, *export
, *end
;
2327 if (!(symname
= strchr(line
, '\t')))
2330 if (!(modname
= strchr(symname
, '\t')))
2333 if ((export
= strchr(modname
, '\t')) != NULL
)
2335 if (export
&& ((end
= strchr(export
, '\t')) != NULL
))
2337 crc
= strtoul(line
, &d
, 16);
2338 if (*symname
== '\0' || *modname
== '\0' || *d
!= '\0')
2340 mod
= find_module(modname
);
2342 if (is_vmlinux(modname
))
2344 mod
= new_module(modname
);
2347 s
= sym_add_exported(symname
, mod
, export_no(export
));
2350 sym_update_crc(symname
, mod
, crc
, export_no(export
));
2352 release_file(file
, size
);
2355 release_file(file
, size
);
2356 fatal("parse error in symbol dump file\n");
2359 /* For normal builds always dump all symbols.
2360 * For external modules only dump symbols
2361 * that are not read from kernel Module.symvers.
2363 static int dump_sym(struct symbol
*sym
)
2365 if (!external_module
)
2367 if (sym
->vmlinux
|| sym
->kernel
)
2372 static void write_dump(const char *fname
)
2374 struct buffer buf
= { };
2375 struct symbol
*symbol
;
2378 for (n
= 0; n
< SYMBOL_HASH_SIZE
; n
++) {
2379 symbol
= symbolhash
[n
];
2381 if (dump_sym(symbol
))
2382 buf_printf(&buf
, "0x%08x\t%s\t%s\t%s\n",
2383 symbol
->crc
, symbol
->name
,
2384 symbol
->module
->name
,
2385 export_str(symbol
->export
));
2386 symbol
= symbol
->next
;
2389 write_if_changed(&buf
, fname
);
2393 struct ext_sym_list
{
2394 struct ext_sym_list
*next
;
2398 int main(int argc
, char **argv
)
2401 struct buffer buf
= { };
2402 char *kernel_read
= NULL
, *module_read
= NULL
;
2403 char *dump_write
= NULL
, *files_source
= NULL
;
2406 struct ext_sym_list
*extsym_iter
;
2407 struct ext_sym_list
*extsym_start
= NULL
;
2409 while ((opt
= getopt(argc
, argv
, "i:I:e:mnsST:o:awM:K:E")) != -1) {
2412 kernel_read
= optarg
;
2415 module_read
= optarg
;
2416 external_module
= 1;
2419 external_module
= 1;
2421 NOFAIL(malloc(sizeof(*extsym_iter
)));
2422 extsym_iter
->next
= extsym_start
;
2423 extsym_iter
->file
= optarg
;
2424 extsym_start
= extsym_iter
;
2430 ignore_missing_files
= 1;
2433 dump_write
= optarg
;
2439 vmlinux_section_warnings
= 0;
2442 sec_mismatch_verbose
= 0;
2445 files_source
= optarg
;
2448 warn_unresolved
= 1;
2451 sec_mismatch_fatal
= 1;
2459 read_dump(kernel_read
, 1);
2461 read_dump(module_read
, 0);
2462 while (extsym_start
) {
2463 read_dump(extsym_start
->file
, 0);
2464 extsym_iter
= extsym_start
->next
;
2466 extsym_start
= extsym_iter
;
2469 while (optind
< argc
)
2470 read_symbols(argv
[optind
++]);
2473 read_symbols_from_files(files_source
);
2475 for (mod
= modules
; mod
; mod
= mod
->next
) {
2483 for (mod
= modules
; mod
; mod
= mod
->next
) {
2484 char fname
[PATH_MAX
];
2491 add_header(&buf
, mod
);
2492 add_intree_flag(&buf
, !external_module
);
2493 add_staging_flag(&buf
, mod
->name
);
2494 err
|= add_versions(&buf
, mod
);
2495 add_depends(&buf
, mod
, modules
);
2496 add_moddevtable(&buf
, mod
);
2497 add_srcversion(&buf
, mod
);
2499 sprintf(fname
, "%s.mod.c", mod
->name
);
2500 write_if_changed(&buf
, fname
);
2503 write_dump(dump_write
);
2504 if (sec_mismatch_count
) {
2505 if (!sec_mismatch_verbose
) {
2506 warn("modpost: Found %d section mismatch(es).\n"
2507 "To see full details build your kernel with:\n"
2508 "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
2509 sec_mismatch_count
);
2511 if (sec_mismatch_fatal
) {
2512 fatal("modpost: Section mismatches detected.\n"
2513 "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n");