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