*
* Copyright 2003 Kai Germaschewski
* Copyright 2002-2004 Rusty Russell, IBM Corporation
- *
+ * Copyright 2006-2008 Sam Ravnborg
* Based in part on module-init-tools/depmod.c,file2alias
*
* This software may be used and distributed according to the terms
* Usage: modpost vmlinux module1.o module2.o ...
*/
+#define _GNU_SOURCE
+#include <stdio.h>
#include <ctype.h>
#include "modpost.h"
+#include "../../include/linux/license.h"
/* Are we using CONFIG_MODVERSIONS? */
int modversions = 0;
int have_vmlinux = 0;
/* Is CONFIG_MODULE_SRCVERSION_ALL set? */
static int all_versions = 0;
+/* If we are modposting external module set to 1 */
+static int external_module = 0;
+/* Warn about section mismatch in vmlinux if set to 1 */
+static int vmlinux_section_warnings = 1;
+/* Only warn about unresolved symbols */
+static int warn_unresolved = 0;
+/* How a symbol is exported */
+static int sec_mismatch_count = 0;
+static int sec_mismatch_verbose = 1;
+
+enum export {
+ export_plain, export_unused, export_gpl,
+ export_unused_gpl, export_gpl_future, export_unknown
+};
-void
-fatal(const char *fmt, ...)
+#define PRINTF __attribute__ ((format (printf, 1, 2)))
+
+PRINTF void fatal(const char *fmt, ...)
{
va_list arglist;
exit(1);
}
-void
-warn(const char *fmt, ...)
+PRINTF void warn(const char *fmt, ...)
{
va_list arglist;
va_end(arglist);
}
+PRINTF void merror(const char *fmt, ...)
+{
+ va_list arglist;
+
+ fprintf(stderr, "ERROR: ");
+
+ va_start(arglist, fmt);
+ vfprintf(stderr, fmt, arglist);
+ va_end(arglist);
+}
+
+static int is_vmlinux(const char *modname)
+{
+ const char *myname;
+
+ myname = strrchr(modname, '/');
+ if (myname)
+ myname++;
+ else
+ myname = modname;
+
+ return (strcmp(myname, "vmlinux") == 0) ||
+ (strcmp(myname, "vmlinux.o") == 0);
+}
+
void *do_nofail(void *ptr, const char *expr)
{
- if (!ptr) {
+ if (!ptr)
fatal("modpost: Memory allocation failure: %s.\n", expr);
- }
+
return ptr;
}
/* A list of all modules we processed */
-
static struct module *modules;
-struct module *
-find_module(char *modname)
+static struct module *find_module(char *modname)
{
struct module *mod;
return mod;
}
-struct module *
-new_module(char *modname)
+static struct module *new_module(char *modname)
{
struct module *mod;
char *p, *s;
-
+
mod = NOFAIL(malloc(sizeof(*mod)));
memset(mod, 0, sizeof(*mod));
p = NOFAIL(strdup(modname));
/* strip trailing .o */
- if ((s = strrchr(p, '.')) != NULL)
+ s = strrchr(p, '.');
+ if (s != NULL)
if (strcmp(s, ".o") == 0)
*s = '\0';
/* add to list */
mod->name = p;
+ mod->gpl_compatible = -1;
mod->next = modules;
modules = mod;
unsigned int crc;
int crc_valid;
unsigned int weak:1;
+ unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */
+ unsigned int kernel:1; /* 1 if symbol is from kernel
+ * (only for external modules) **/
+ unsigned int preloaded:1; /* 1 if symbol from Module.symvers */
+ enum export export; /* Type of export */
char name[0];
};
unsigned i; /* Used to cycle through random values. */
/* Set the initial value from the key size. */
- for (value = 0x238F13AF * strlen(name), i=0; name[i]; i++)
+ for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++)
value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
return (1103515243 * value + 12345);
}
-/* Allocate a new symbols for use in the hash of exported symbols or
- * the list of unresolved symbols per module */
-
-struct symbol *
-alloc_symbol(const char *name, unsigned int weak, struct symbol *next)
+/**
+ * Allocate a new symbols for use in the hash of exported symbols or
+ * the list of unresolved symbols per module
+ **/
+static struct symbol *alloc_symbol(const char *name, unsigned int weak,
+ struct symbol *next)
{
struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
}
/* For the hash of exported symbols */
-
-void
-new_symbol(const char *name, struct module *module, unsigned int *crc)
+static struct symbol *new_symbol(const char *name, struct module *module,
+ enum export export)
{
unsigned int hash;
struct symbol *new;
hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
new->module = module;
- if (crc) {
- new->crc = *crc;
- new->crc_valid = 1;
- }
+ new->export = export;
+ return new;
}
-struct symbol *
-find_symbol(const char *name)
+static struct symbol *find_symbol(const char *name)
{
struct symbol *s;
if (name[0] == '.')
name++;
- for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s=s->next) {
+ for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
if (strcmp(s->name, name) == 0)
return s;
}
return NULL;
}
-/* Add an exported symbol - it may have already been added without a
- * CRC, in this case just update the CRC */
-void
-add_exported_symbol(const char *name, struct module *module, unsigned int *crc)
+static struct {
+ const char *str;
+ enum export export;
+} export_list[] = {
+ { .str = "EXPORT_SYMBOL", .export = export_plain },
+ { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
+ { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
+ { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
+ { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
+ { .str = "(unknown)", .export = export_unknown },
+};
+
+
+static const char *export_str(enum export ex)
+{
+ return export_list[ex].str;
+}
+
+static enum export export_no(const char *s)
+{
+ int i;
+
+ if (!s)
+ return export_unknown;
+ for (i = 0; export_list[i].export != export_unknown; i++) {
+ if (strcmp(export_list[i].str, s) == 0)
+ return export_list[i].export;
+ }
+ return export_unknown;
+}
+
+static enum export export_from_sec(struct elf_info *elf, Elf_Section sec)
+{
+ if (sec == elf->export_sec)
+ return export_plain;
+ else if (sec == elf->export_unused_sec)
+ return export_unused;
+ else if (sec == elf->export_gpl_sec)
+ return export_gpl;
+ else if (sec == elf->export_unused_gpl_sec)
+ return export_unused_gpl;
+ else if (sec == elf->export_gpl_future_sec)
+ return export_gpl_future;
+ else
+ return export_unknown;
+}
+
+/**
+ * Add an exported symbol - it may have already been added without a
+ * CRC, in this case just update the CRC
+ **/
+static struct symbol *sym_add_exported(const char *name, struct module *mod,
+ enum export export)
{
struct symbol *s = find_symbol(name);
if (!s) {
- new_symbol(name, module, crc);
- return;
- }
- if (crc) {
- s->crc = *crc;
- s->crc_valid = 1;
+ s = new_symbol(name, mod, export);
+ } else {
+ if (!s->preloaded) {
+ warn("%s: '%s' exported twice. Previous export "
+ "was in %s%s\n", mod->name, name,
+ s->module->name,
+ is_vmlinux(s->module->name) ?"":".ko");
+ } else {
+ /* In case Modules.symvers was out of date */
+ s->module = mod;
+ }
}
+ s->preloaded = 0;
+ s->vmlinux = is_vmlinux(mod->name);
+ s->kernel = 0;
+ s->export = export;
+ return s;
+}
+
+static void sym_update_crc(const char *name, struct module *mod,
+ unsigned int crc, enum export export)
+{
+ struct symbol *s = find_symbol(name);
+
+ if (!s)
+ s = new_symbol(name, mod, export);
+ s->crc = crc;
+ s->crc_valid = 1;
}
-void *
-grab_file(const char *filename, unsigned long *size)
+void *grab_file(const char *filename, unsigned long *size)
{
struct stat st;
void *map;
return map;
}
-/*
- Return a copy of the next line in a mmap'ed file.
- spaces in the beginning of the line is trimmed away.
- Return a pointer to a static buffer.
-*/
-char*
-get_next_line(unsigned long *pos, void *file, unsigned long size)
+/**
+ * Return a copy of the next line in a mmap'ed file.
+ * spaces in the beginning of the line is trimmed away.
+ * Return a pointer to a static buffer.
+ **/
+char *get_next_line(unsigned long *pos, void *file, unsigned long size)
{
static char line[4096];
int skip = 1;
signed char *p = (signed char *)file + *pos;
char *s = line;
- for (; *pos < size ; (*pos)++)
- {
+ for (; *pos < size ; (*pos)++) {
if (skip && isspace(*p)) {
p++;
continue;
return NULL;
}
-void
-release_file(void *file, unsigned long size)
+void release_file(void *file, unsigned long size)
{
munmap(file, size);
}
-void
-parse_elf(struct elf_info *info, const char *filename)
+static int parse_elf(struct elf_info *info, const char *filename)
{
unsigned int i;
- Elf_Ehdr *hdr = info->hdr;
+ Elf_Ehdr *hdr;
Elf_Shdr *sechdrs;
Elf_Sym *sym;
hdr = grab_file(filename, &info->size);
if (!hdr) {
perror(filename);
- abort();
+ exit(1);
}
info->hdr = hdr;
- if (info->size < sizeof(*hdr))
- goto truncated;
-
+ if (info->size < sizeof(*hdr)) {
+ /* file too small, assume this is an empty .o file */
+ return 0;
+ }
+ /* Is this a valid ELF file? */
+ if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
+ (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
+ (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
+ (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
+ /* Not an ELF file - silently ignore it */
+ return 0;
+ }
/* Fix endianness in ELF header */
hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
hdr->e_machine = TO_NATIVE(hdr->e_machine);
+ hdr->e_type = TO_NATIVE(hdr->e_type);
sechdrs = (void *)hdr + hdr->e_shoff;
info->sechdrs = sechdrs;
+ /* Check if file offset is correct */
+ if (hdr->e_shoff > info->size) {
+ fatal("section header offset=%lu in file '%s' is bigger than "
+ "filesize=%lu\n", (unsigned long)hdr->e_shoff,
+ filename, info->size);
+ return 0;
+ }
+
/* Fix endianness in section headers */
for (i = 0; i < hdr->e_shnum; i++) {
sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
+ sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
+ sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
}
/* Find symbol table. */
for (i = 1; i < hdr->e_shnum; i++) {
const char *secstrings
= (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
-
- if (sechdrs[i].sh_offset > info->size)
- goto truncated;
- if (strcmp(secstrings+sechdrs[i].sh_name, ".modinfo") == 0) {
+ const char *secname;
+
+ if (sechdrs[i].sh_offset > info->size) {
+ fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
+ "sizeof(*hrd)=%zu\n", filename,
+ (unsigned long)sechdrs[i].sh_offset,
+ sizeof(*hdr));
+ return 0;
+ }
+ secname = secstrings + sechdrs[i].sh_name;
+ if (strcmp(secname, ".modinfo") == 0) {
info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
info->modinfo_len = sechdrs[i].sh_size;
- }
+ } else if (strcmp(secname, "__ksymtab") == 0)
+ info->export_sec = i;
+ else if (strcmp(secname, "__ksymtab_unused") == 0)
+ info->export_unused_sec = i;
+ else if (strcmp(secname, "__ksymtab_gpl") == 0)
+ info->export_gpl_sec = i;
+ else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
+ info->export_unused_gpl_sec = i;
+ else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
+ info->export_gpl_future_sec = i;
+ else if (strcmp(secname, "__markers_strings") == 0)
+ info->markers_strings_sec = i;
+
if (sechdrs[i].sh_type != SHT_SYMTAB)
continue;
info->symtab_start = (void *)hdr + sechdrs[i].sh_offset;
- info->symtab_stop = (void *)hdr + sechdrs[i].sh_offset
+ info->symtab_stop = (void *)hdr + sechdrs[i].sh_offset
+ sechdrs[i].sh_size;
- info->strtab = (void *)hdr +
+ info->strtab = (void *)hdr +
sechdrs[sechdrs[i].sh_link].sh_offset;
}
- if (!info->symtab_start) {
- fprintf(stderr, "modpost: %s no symtab?\n", filename);
- abort();
- }
+ if (!info->symtab_start)
+ fatal("%s has no symtab?\n", filename);
+
/* Fix endianness in symbols */
for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
sym->st_shndx = TO_NATIVE(sym->st_shndx);
sym->st_value = TO_NATIVE(sym->st_value);
sym->st_size = TO_NATIVE(sym->st_size);
}
- return;
-
- truncated:
- fprintf(stderr, "modpost: %s is truncated.\n", filename);
- abort();
+ return 1;
}
-void
-parse_elf_finish(struct elf_info *info)
+static void parse_elf_finish(struct elf_info *info)
{
release_file(info->hdr, info->size);
}
#define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_"
#define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
-void
-handle_modversions(struct module *mod, struct elf_info *info,
- Elf_Sym *sym, const char *symname)
+static void handle_modversions(struct module *mod, struct elf_info *info,
+ Elf_Sym *sym, const char *symname)
{
unsigned int crc;
+ enum export export = export_from_sec(info, sym->st_shndx);
switch (sym->st_shndx) {
case SHN_COMMON:
- fprintf(stderr, "*** Warning: \"%s\" [%s] is COMMON symbol\n",
- symname, mod->name);
+ warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
break;
case SHN_ABS:
/* CRC'd symbol */
if (memcmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
crc = (unsigned int) sym->st_value;
- add_exported_symbol(symname + strlen(CRC_PFX),
- mod, &crc);
+ sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
+ export);
}
break;
case SHN_UNDEF:
/* Ignore register directives. */
if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
break;
- if (symname[0] == '.') {
- char *munged = strdup(symname);
- munged[0] = '_';
- munged[1] = toupper(munged[1]);
- symname = munged;
- }
+ if (symname[0] == '.') {
+ char *munged = strdup(symname);
+ munged[0] = '_';
+ munged[1] = toupper(munged[1]);
+ symname = munged;
+ }
}
#endif
-
+
if (memcmp(symname, MODULE_SYMBOL_PREFIX,
- strlen(MODULE_SYMBOL_PREFIX)) == 0)
- mod->unres = alloc_symbol(symname +
- strlen(MODULE_SYMBOL_PREFIX),
- ELF_ST_BIND(sym->st_info) == STB_WEAK,
- mod->unres);
+ strlen(MODULE_SYMBOL_PREFIX)) == 0) {
+ mod->unres =
+ alloc_symbol(symname +
+ strlen(MODULE_SYMBOL_PREFIX),
+ ELF_ST_BIND(sym->st_info) == STB_WEAK,
+ mod->unres);
+ }
break;
default:
/* All exported symbols */
if (memcmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
- add_exported_symbol(symname + strlen(KSYMTAB_PFX),
- mod, NULL);
+ sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
+ export);
}
if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
mod->has_init = 1;
}
}
-int
-is_vmlinux(const char *modname)
-{
- const char *myname;
-
- if ((myname = strrchr(modname, '/')))
- myname++;
- else
- myname = modname;
-
- return strcmp(myname, "vmlinux") == 0;
-}
-
-/* Parse tag=value strings from .modinfo section */
+/**
+ * Parse tag=value strings from .modinfo section
+ **/
static char *next_string(char *string, unsigned long *secsize)
{
/* Skip non-zero chars */
return string;
}
-static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
- const char *tag)
+static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
+ const char *tag, char *info)
{
char *p;
unsigned int taglen = strlen(tag);
unsigned long size = modinfo_len;
+ if (info) {
+ size -= info - (char *)modinfo;
+ modinfo = next_string(info, &size);
+ }
+
for (p = modinfo; p; p = next_string(p, &size)) {
if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
return p + taglen + 1;
return NULL;
}
-void
-read_symbols(char *modname)
+static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
+ const char *tag)
+
+{
+ return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
+}
+
+/**
+ * Test if string s ends in string sub
+ * return 0 if match
+ **/
+static int strrcmp(const char *s, const char *sub)
+{
+ int slen, sublen;
+
+ if (!s || !sub)
+ return 1;
+
+ slen = strlen(s);
+ sublen = strlen(sub);
+
+ if ((slen == 0) || (sublen == 0))
+ return 1;
+
+ if (sublen > slen)
+ return 1;
+
+ return memcmp(s + slen - sublen, sub, sublen);
+}
+
+static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
+{
+ if (sym)
+ return elf->strtab + sym->st_name;
+ else
+ return "(unknown)";
+}
+
+static const char *sec_name(struct elf_info *elf, int shndx)
+{
+ Elf_Shdr *sechdrs = elf->sechdrs;
+ return (void *)elf->hdr +
+ elf->sechdrs[elf->hdr->e_shstrndx].sh_offset +
+ sechdrs[shndx].sh_name;
+}
+
+static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr)
+{
+ return (void *)elf->hdr +
+ elf->sechdrs[elf->hdr->e_shstrndx].sh_offset +
+ sechdr->sh_name;
+}
+
+/* if sym is empty or point to a string
+ * like ".[0-9]+" then return 1.
+ * This is the optional prefix added by ld to some sections
+ */
+static int number_prefix(const char *sym)
+{
+ if (*sym++ == '\0')
+ return 1;
+ if (*sym != '.')
+ return 0;
+ do {
+ char c = *sym++;
+ if (c < '0' || c > '9')
+ return 0;
+ } while (*sym);
+ return 1;
+}
+
+/* The pattern is an array of simple patterns.
+ * "foo" will match an exact string equal to "foo"
+ * "*foo" will match a string that ends with "foo"
+ * "foo*" will match a string that begins with "foo"
+ * "foo$" will match a string equal to "foo" or "foo.1"
+ * where the '1' can be any number including several digits.
+ * The $ syntax is for sections where ld append a dot number
+ * to make section name unique.
+ */
+int match(const char *sym, const char * const pat[])
+{
+ const char *p;
+ while (*pat) {
+ p = *pat++;
+ const char *endp = p + strlen(p) - 1;
+
+ /* "*foo" */
+ if (*p == '*') {
+ if (strrcmp(sym, p + 1) == 0)
+ return 1;
+ }
+ /* "foo*" */
+ else if (*endp == '*') {
+ if (strncmp(sym, p, strlen(p) - 1) == 0)
+ return 1;
+ }
+ /* "foo$" */
+ else if (*endp == '$') {
+ if (strncmp(sym, p, strlen(p) - 1) == 0) {
+ if (number_prefix(sym + strlen(p) - 1))
+ return 1;
+ }
+ }
+ /* no wildcards */
+ else {
+ if (strcmp(p, sym) == 0)
+ return 1;
+ }
+ }
+ /* no match */
+ return 0;
+}
+
+/* sections that we do not want to do full section mismatch check on */
+static const char *section_white_list[] =
+ { ".debug*", ".stab*", ".note*", ".got*", ".toc*", NULL };
+
+/*
+ * Is this section one we do not want to check?
+ * This is often debug sections.
+ * If we are going to check this section then
+ * test if section name ends with a dot and a number.
+ * This is used to find sections where the linker have
+ * appended a dot-number to make the name unique.
+ * The cause of this is often a section specified in assembler
+ * without "ax" / "aw" and the same section used in .c
+ * code where gcc add these.
+ */
+static int check_section(const char *modname, const char *sec)
+{
+ const char *e = sec + strlen(sec) - 1;
+ if (match(sec, section_white_list))
+ return 1;
+
+ if (*e && isdigit(*e)) {
+ /* consume all digits */
+ while (*e && e != sec && isdigit(*e))
+ e--;
+ if (*e == '.') {
+ warn("%s (%s): unexpected section name.\n"
+ "The (.[number]+) following section name are "
+ "ld generated and not expected.\n"
+ "Did you forget to use \"ax\"/\"aw\" "
+ "in a .S file?\n"
+ "Note that for example <linux/init.h> contains\n"
+ "section definitions for use in .S files.\n\n",
+ modname, sec);
+ }
+ }
+ return 0;
+}
+
+
+
+#define ALL_INIT_DATA_SECTIONS \
+ ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$"
+#define ALL_EXIT_DATA_SECTIONS \
+ ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$"
+
+#define ALL_INIT_TEXT_SECTIONS \
+ ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$"
+#define ALL_EXIT_TEXT_SECTIONS \
+ ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$"
+
+#define ALL_INIT_SECTIONS ALL_INIT_DATA_SECTIONS, ALL_INIT_TEXT_SECTIONS
+#define ALL_EXIT_SECTIONS ALL_EXIT_DATA_SECTIONS, ALL_EXIT_TEXT_SECTIONS
+
+#define DATA_SECTIONS ".data$", ".data.rel$"
+#define TEXT_SECTIONS ".text$"
+
+#define INIT_SECTIONS ".init.data$", ".init.text$"
+#define DEV_INIT_SECTIONS ".devinit.data$", ".devinit.text$"
+#define CPU_INIT_SECTIONS ".cpuinit.data$", ".cpuinit.text$"
+#define MEM_INIT_SECTIONS ".meminit.data$", ".meminit.text$"
+
+#define EXIT_SECTIONS ".exit.data$", ".exit.text$"
+#define DEV_EXIT_SECTIONS ".devexit.data$", ".devexit.text$"
+#define CPU_EXIT_SECTIONS ".cpuexit.data$", ".cpuexit.text$"
+#define MEM_EXIT_SECTIONS ".memexit.data$", ".memexit.text$"
+
+/* init data sections */
+static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL };
+
+/* all init sections */
+static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL };
+
+/* All init and exit sections (code + data) */
+static const char *init_exit_sections[] =
+ {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
+
+/* data section */
+static const char *data_sections[] = { DATA_SECTIONS, NULL };
+
+/* sections that may refer to an init/exit section with no warning */
+static const char *initref_sections[] =
+{
+ ".text.init.refok*",
+ ".exit.text.refok*",
+ ".data.init.refok*",
+ NULL
+};
+
+
+/* symbols in .data that may refer to init/exit sections */
+static const char *symbol_white_list[] =
+{
+ "*driver",
+ "*_template", /* scsi uses *_template a lot */
+ "*_timer", /* arm uses ops structures named _timer a lot */
+ "*_sht", /* scsi also used *_sht to some extent */
+ "*_ops",
+ "*_probe",
+ "*_probe_one",
+ "*_console",
+ NULL
+};
+
+static const char *head_sections[] = { ".head.text*", NULL };
+static const char *linker_symbols[] =
+ { "__init_begin", "_sinittext", "_einittext", NULL };
+
+enum mismatch {
+ NO_MISMATCH,
+ TEXT_TO_INIT,
+ DATA_TO_INIT,
+ TEXT_TO_EXIT,
+ DATA_TO_EXIT,
+ XXXINIT_TO_INIT,
+ XXXEXIT_TO_EXIT,
+ INIT_TO_EXIT,
+ EXIT_TO_INIT,
+ EXPORT_TO_INIT_EXIT,
+};
+
+struct sectioncheck {
+ const char *fromsec[20];
+ const char *tosec[20];
+ enum mismatch mismatch;
+};
+
+const struct sectioncheck sectioncheck[] = {
+/* Do not reference init/exit code/data from
+ * normal code and data
+ */
+{
+ .fromsec = { TEXT_SECTIONS, NULL },
+ .tosec = { ALL_INIT_SECTIONS, NULL },
+ .mismatch = TEXT_TO_INIT,
+},
+{
+ .fromsec = { DATA_SECTIONS, NULL },
+ .tosec = { ALL_INIT_SECTIONS, NULL },
+ .mismatch = DATA_TO_INIT,
+},
+{
+ .fromsec = { TEXT_SECTIONS, NULL },
+ .tosec = { ALL_EXIT_SECTIONS, NULL },
+ .mismatch = TEXT_TO_EXIT,
+},
+{
+ .fromsec = { DATA_SECTIONS, NULL },
+ .tosec = { ALL_EXIT_SECTIONS, NULL },
+ .mismatch = DATA_TO_EXIT,
+},
+/* Do not reference init code/data from devinit/cpuinit/meminit code/data */
+{
+ .fromsec = { DEV_INIT_SECTIONS, CPU_INIT_SECTIONS, MEM_INIT_SECTIONS, NULL },
+ .tosec = { INIT_SECTIONS, NULL },
+ .mismatch = XXXINIT_TO_INIT,
+},
+/* Do not reference exit code/data from devexit/cpuexit/memexit code/data */
+{
+ .fromsec = { DEV_EXIT_SECTIONS, CPU_EXIT_SECTIONS, MEM_EXIT_SECTIONS, NULL },
+ .tosec = { EXIT_SECTIONS, NULL },
+ .mismatch = XXXEXIT_TO_EXIT,
+},
+/* Do not use exit code/data from init code */
+{
+ .fromsec = { ALL_INIT_SECTIONS, NULL },
+ .tosec = { ALL_EXIT_SECTIONS, NULL },
+ .mismatch = INIT_TO_EXIT,
+},
+/* Do not use init code/data from exit code */
+{
+ .fromsec = { ALL_EXIT_SECTIONS, NULL },
+ .tosec = { ALL_INIT_SECTIONS, NULL },
+ .mismatch = EXIT_TO_INIT,
+},
+/* Do not export init/exit functions or data */
+{
+ .fromsec = { "__ksymtab*", NULL },
+ .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
+ .mismatch = EXPORT_TO_INIT_EXIT
+}
+};
+
+static int section_mismatch(const char *fromsec, const char *tosec)
+{
+ int i;
+ int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
+ const struct sectioncheck *check = §ioncheck[0];
+
+ for (i = 0; i < elems; i++) {
+ if (match(fromsec, check->fromsec) &&
+ match(tosec, check->tosec))
+ return check->mismatch;
+ check++;
+ }
+ return NO_MISMATCH;
+}
+
+/**
+ * Whitelist to allow certain references to pass with no warning.
+ *
+ * Pattern 0:
+ * Do not warn if funtion/data are marked with __init_refok/__initdata_refok.
+ * The pattern is identified by:
+ * fromsec = .text.init.refok* | .data.init.refok*
+ *
+ * Pattern 1:
+ * If a module parameter is declared __initdata and permissions=0
+ * then this is legal despite the warning generated.
+ * We cannot see value of permissions here, so just ignore
+ * this pattern.
+ * The pattern is identified by:
+ * tosec = .init.data
+ * fromsec = .data*
+ * atsym =__param*
+ *
+ * Pattern 2:
+ * Many drivers utilise a *driver container with references to
+ * add, remove, probe functions etc.
+ * These functions may often be marked __init and we do not want to
+ * warn here.
+ * the pattern is identified by:
+ * tosec = init or exit section
+ * fromsec = data section
+ * atsym = *driver, *_template, *_sht, *_ops, *_probe,
+ * *probe_one, *_console, *_timer
+ *
+ * Pattern 3:
+ * Whitelist all refereces from .text.head to .init.data
+ * Whitelist all refereces from .text.head to .init.text
+ *
+ * Pattern 4:
+ * Some symbols belong to init section but still it is ok to reference
+ * these from non-init sections as these symbols don't have any memory
+ * allocated for them and symbol address and value are same. So even
+ * if init section is freed, its ok to reference those symbols.
+ * For ex. symbols marking the init section boundaries.
+ * This pattern is identified by
+ * refsymname = __init_begin, _sinittext, _einittext
+ *
+ **/
+static int secref_whitelist(const char *fromsec, const char *fromsym,
+ const char *tosec, const char *tosym)
+{
+ /* Check for pattern 0 */
+ if (match(fromsec, initref_sections))
+ return 0;
+
+ /* Check for pattern 1 */
+ if (match(tosec, init_data_sections) &&
+ match(fromsec, data_sections) &&
+ (strncmp(fromsym, "__param", strlen("__param")) == 0))
+ return 0;
+
+ /* Check for pattern 2 */
+ if (match(tosec, init_exit_sections) &&
+ match(fromsec, data_sections) &&
+ match(fromsym, symbol_white_list))
+ return 0;
+
+ /* Check for pattern 3 */
+ if (match(fromsec, head_sections) &&
+ match(tosec, init_sections))
+ return 0;
+
+ /* Check for pattern 4 */
+ if (match(tosym, linker_symbols))
+ return 0;
+
+ return 1;
+}
+
+/**
+ * Find symbol based on relocation record info.
+ * In some cases the symbol supplied is a valid symbol so
+ * return refsym. If st_name != 0 we assume this is a valid symbol.
+ * In other cases the symbol needs to be looked up in the symbol table
+ * based on section and address.
+ * **/
+static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr,
+ Elf_Sym *relsym)
+{
+ Elf_Sym *sym;
+ Elf_Sym *near = NULL;
+ Elf64_Sword distance = 20;
+ Elf64_Sword d;
+
+ if (relsym->st_name != 0)
+ return relsym;
+ for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
+ if (sym->st_shndx != relsym->st_shndx)
+ continue;
+ if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
+ continue;
+ if (sym->st_value == addr)
+ return sym;
+ /* Find a symbol nearby - addr are maybe negative */
+ d = sym->st_value - addr;
+ if (d < 0)
+ d = addr - sym->st_value;
+ if (d < distance) {
+ distance = d;
+ near = sym;
+ }
+ }
+ /* We need a close match */
+ if (distance < 20)
+ return near;
+ else
+ return NULL;
+}
+
+static inline int is_arm_mapping_symbol(const char *str)
+{
+ return str[0] == '$' && strchr("atd", str[1])
+ && (str[2] == '\0' || str[2] == '.');
+}
+
+/*
+ * If there's no name there, ignore it; likewise, ignore it if it's
+ * one of the magic symbols emitted used by current ARM tools.
+ *
+ * Otherwise if find_symbols_between() returns those symbols, they'll
+ * fail the whitelist tests and cause lots of false alarms ... fixable
+ * only by merging __exit and __init sections into __text, bloating
+ * the kernel (which is especially evil on embedded platforms).
+ */
+static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
+{
+ const char *name = elf->strtab + sym->st_name;
+
+ if (!name || !strlen(name))
+ return 0;
+ return !is_arm_mapping_symbol(name);
+}
+
+/*
+ * Find symbols before or equal addr and after addr - in the section sec.
+ * If we find two symbols with equal offset prefer one with a valid name.
+ * The ELF format may have a better way to detect what type of symbol
+ * it is, but this works for now.
+ **/
+static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
+ const char *sec)
+{
+ Elf_Sym *sym;
+ Elf_Sym *near = NULL;
+ Elf_Addr distance = ~0;
+
+ for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
+ const char *symsec;
+
+ if (sym->st_shndx >= SHN_LORESERVE)
+ continue;
+ symsec = sec_name(elf, sym->st_shndx);
+ if (strcmp(symsec, sec) != 0)
+ continue;
+ if (!is_valid_name(elf, sym))
+ continue;
+ if (sym->st_value <= addr) {
+ if ((addr - sym->st_value) < distance) {
+ distance = addr - sym->st_value;
+ near = sym;
+ } else if ((addr - sym->st_value) == distance) {
+ near = sym;
+ }
+ }
+ }
+ return near;
+}
+
+/*
+ * Convert a section name to the function/data attribute
+ * .init.text => __init
+ * .cpuinit.data => __cpudata
+ * .memexitconst => __memconst
+ * etc.
+*/
+static char *sec2annotation(const char *s)
+{
+ if (match(s, init_exit_sections)) {
+ char *p = malloc(20);
+ char *r = p;
+
+ *p++ = '_';
+ *p++ = '_';
+ if (*s == '.')
+ s++;
+ while (*s && *s != '.')
+ *p++ = *s++;
+ *p = '\0';
+ if (*s == '.')
+ s++;
+ if (strstr(s, "rodata") != NULL)
+ strcat(p, "const ");
+ else if (strstr(s, "data") != NULL)
+ strcat(p, "data ");
+ else
+ strcat(p, " ");
+ return r; /* we leak her but we do not care */
+ } else {
+ return "";
+ }
+}
+
+static int is_function(Elf_Sym *sym)
+{
+ if (sym)
+ return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
+ else
+ return -1;
+}
+
+/*
+ * Print a warning about a section mismatch.
+ * Try to find symbols near it so user can find it.
+ * Check whitelist before warning - it may be a false positive.
+ */
+static void report_sec_mismatch(const char *modname, enum mismatch mismatch,
+ const char *fromsec,
+ unsigned long long fromaddr,
+ const char *fromsym,
+ int from_is_func,
+ const char *tosec, const char *tosym,
+ int to_is_func)
+{
+ const char *from, *from_p;
+ const char *to, *to_p;
+
+ switch (from_is_func) {
+ case 0: from = "variable"; from_p = ""; break;
+ case 1: from = "function"; from_p = "()"; break;
+ default: from = "(unknown reference)"; from_p = ""; break;
+ }
+ switch (to_is_func) {
+ case 0: to = "variable"; to_p = ""; break;
+ case 1: to = "function"; to_p = "()"; break;
+ default: to = "(unknown reference)"; to_p = ""; break;
+ }
+
+ sec_mismatch_count++;
+ if (!sec_mismatch_verbose)
+ return;
+
+ warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s "
+ "to the %s %s:%s%s\n",
+ modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec,
+ tosym, to_p);
+
+ switch (mismatch) {
+ case TEXT_TO_INIT:
+ fprintf(stderr,
+ "The function %s%s() references\n"
+ "the %s %s%s%s.\n"
+ "This is often because %s lacks a %s\n"
+ "annotation or the annotation of %s is wrong.\n",
+ sec2annotation(fromsec), fromsym,
+ to, sec2annotation(tosec), tosym, to_p,
+ fromsym, sec2annotation(tosec), tosym);
+ break;
+ case DATA_TO_INIT: {
+ const char **s = symbol_white_list;
+ fprintf(stderr,
+ "The variable %s references\n"
+ "the %s %s%s%s\n"
+ "If the reference is valid then annotate the\n"
+ "variable with __init* (see linux/init.h) "
+ "or name the variable:\n",
+ fromsym, to, sec2annotation(tosec), tosym, to_p);
+ while (*s)
+ fprintf(stderr, "%s, ", *s++);
+ fprintf(stderr, "\n");
+ break;
+ }
+ case TEXT_TO_EXIT:
+ fprintf(stderr,
+ "The function %s() references a %s in an exit section.\n"
+ "Often the %s %s%s has valid usage outside the exit section\n"
+ "and the fix is to remove the %sannotation of %s.\n",
+ fromsym, to, to, tosym, to_p, sec2annotation(tosec), tosym);
+ break;
+ case DATA_TO_EXIT: {
+ const char **s = symbol_white_list;
+ fprintf(stderr,
+ "The variable %s references\n"
+ "the %s %s%s%s\n"
+ "If the reference is valid then annotate the\n"
+ "variable with __exit* (see linux/init.h) or "
+ "name the variable:\n",
+ fromsym, to, sec2annotation(tosec), tosym, to_p);
+ while (*s)
+ fprintf(stderr, "%s, ", *s++);
+ fprintf(stderr, "\n");
+ break;
+ }
+ case XXXINIT_TO_INIT:
+ case XXXEXIT_TO_EXIT:
+ fprintf(stderr,
+ "The %s %s%s%s references\n"
+ "a %s %s%s%s.\n"
+ "If %s is only used by %s then\n"
+ "annotate %s with a matching annotation.\n",
+ from, sec2annotation(fromsec), fromsym, from_p,
+ to, sec2annotation(tosec), tosym, to_p,
+ tosym, fromsym, tosym);
+ break;
+ case INIT_TO_EXIT:
+ fprintf(stderr,
+ "The %s %s%s%s references\n"
+ "a %s %s%s%s.\n"
+ "This is often seen when error handling "
+ "in the init function\n"
+ "uses functionality in the exit path.\n"
+ "The fix is often to remove the %sannotation of\n"
+ "%s%s so it may be used outside an exit section.\n",
+ from, sec2annotation(fromsec), fromsym, from_p,
+ to, sec2annotation(tosec), tosym, to_p,
+ sec2annotation(tosec), tosym, to_p);
+ break;
+ case EXIT_TO_INIT:
+ fprintf(stderr,
+ "The %s %s%s%s references\n"
+ "a %s %s%s%s.\n"
+ "This is often seen when error handling "
+ "in the exit function\n"
+ "uses functionality in the init path.\n"
+ "The fix is often to remove the %sannotation of\n"
+ "%s%s so it may be used outside an init section.\n",
+ from, sec2annotation(fromsec), fromsym, from_p,
+ to, sec2annotation(tosec), tosym, to_p,
+ sec2annotation(tosec), tosym, to_p);
+ break;
+ case EXPORT_TO_INIT_EXIT:
+ fprintf(stderr,
+ "The symbol %s is exported and annotated %s\n"
+ "Fix this by removing the %sannotation of %s "
+ "or drop the export.\n",
+ tosym, sec2annotation(tosec), sec2annotation(tosec), tosym);
+ case NO_MISMATCH:
+ /* To get warnings on missing members */
+ break;
+ }
+ fprintf(stderr, "\n");
+}
+
+static void check_section_mismatch(const char *modname, struct elf_info *elf,
+ Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
+{
+ const char *tosec;
+ enum mismatch mismatch;
+
+ tosec = sec_name(elf, sym->st_shndx);
+ mismatch = section_mismatch(fromsec, tosec);
+ if (mismatch != NO_MISMATCH) {
+ Elf_Sym *to;
+ Elf_Sym *from;
+ const char *tosym;
+ const char *fromsym;
+
+ from = find_elf_symbol2(elf, r->r_offset, fromsec);
+ fromsym = sym_name(elf, from);
+ to = find_elf_symbol(elf, r->r_addend, sym);
+ tosym = sym_name(elf, to);
+
+ /* check whitelist - we may ignore it */
+ if (secref_whitelist(fromsec, fromsym, tosec, tosym)) {
+ report_sec_mismatch(modname, mismatch,
+ fromsec, r->r_offset, fromsym,
+ is_function(from), tosec, tosym,
+ is_function(to));
+ }
+ }
+}
+
+static unsigned int *reloc_location(struct elf_info *elf,
+ Elf_Shdr *sechdr, Elf_Rela *r)
+{
+ Elf_Shdr *sechdrs = elf->sechdrs;
+ int section = sechdr->sh_info;
+
+ return (void *)elf->hdr + sechdrs[section].sh_offset +
+ (r->r_offset - sechdrs[section].sh_addr);
+}
+
+static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
+{
+ unsigned int r_typ = ELF_R_TYPE(r->r_info);
+ unsigned int *location = reloc_location(elf, sechdr, r);
+
+ switch (r_typ) {
+ case R_386_32:
+ r->r_addend = TO_NATIVE(*location);
+ break;
+ case R_386_PC32:
+ r->r_addend = TO_NATIVE(*location) + 4;
+ /* For CONFIG_RELOCATABLE=y */
+ if (elf->hdr->e_type == ET_EXEC)
+ r->r_addend += r->r_offset;
+ break;
+ }
+ return 0;
+}
+
+static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
+{
+ unsigned int r_typ = ELF_R_TYPE(r->r_info);
+
+ switch (r_typ) {
+ case R_ARM_ABS32:
+ /* From ARM ABI: (S + A) | T */
+ r->r_addend = (int)(long)
+ (elf->symtab_start + ELF_R_SYM(r->r_info));
+ break;
+ case R_ARM_PC24:
+ /* From ARM ABI: ((S + A) | T) - P */
+ r->r_addend = (int)(long)(elf->hdr +
+ sechdr->sh_offset +
+ (r->r_offset - sechdr->sh_addr));
+ break;
+ default:
+ return 1;
+ }
+ return 0;
+}
+
+static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
+{
+ unsigned int r_typ = ELF_R_TYPE(r->r_info);
+ unsigned int *location = reloc_location(elf, sechdr, r);
+ unsigned int inst;
+
+ if (r_typ == R_MIPS_HI16)
+ return 1; /* skip this */
+ inst = TO_NATIVE(*location);
+ switch (r_typ) {
+ case R_MIPS_LO16:
+ r->r_addend = inst & 0xffff;
+ break;
+ case R_MIPS_26:
+ r->r_addend = (inst & 0x03ffffff) << 2;
+ break;
+ case R_MIPS_32:
+ r->r_addend = inst;
+ break;
+ }
+ return 0;
+}
+
+static void section_rela(const char *modname, struct elf_info *elf,
+ Elf_Shdr *sechdr)
+{
+ Elf_Sym *sym;
+ Elf_Rela *rela;
+ Elf_Rela r;
+ unsigned int r_sym;
+ const char *fromsec;
+
+ Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
+ Elf_Rela *stop = (void *)start + sechdr->sh_size;
+
+ fromsec = sech_name(elf, sechdr);
+ fromsec += strlen(".rela");
+ /* if from section (name) is know good then skip it */
+ if (check_section(modname, fromsec))
+ return;
+
+ for (rela = start; rela < stop; rela++) {
+ r.r_offset = TO_NATIVE(rela->r_offset);
+#if KERNEL_ELFCLASS == ELFCLASS64
+ if (elf->hdr->e_machine == EM_MIPS) {
+ unsigned int r_typ;
+ r_sym = ELF64_MIPS_R_SYM(rela->r_info);
+ r_sym = TO_NATIVE(r_sym);
+ r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
+ r.r_info = ELF64_R_INFO(r_sym, r_typ);
+ } else {
+ r.r_info = TO_NATIVE(rela->r_info);
+ r_sym = ELF_R_SYM(r.r_info);
+ }
+#else
+ r.r_info = TO_NATIVE(rela->r_info);
+ r_sym = ELF_R_SYM(r.r_info);
+#endif
+ r.r_addend = TO_NATIVE(rela->r_addend);
+ sym = elf->symtab_start + r_sym;
+ /* Skip special sections */
+ if (sym->st_shndx >= SHN_LORESERVE)
+ continue;
+ check_section_mismatch(modname, elf, &r, sym, fromsec);
+ }
+}
+
+static void section_rel(const char *modname, struct elf_info *elf,
+ Elf_Shdr *sechdr)
+{
+ Elf_Sym *sym;
+ Elf_Rel *rel;
+ Elf_Rela r;
+ unsigned int r_sym;
+ const char *fromsec;
+
+ Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
+ Elf_Rel *stop = (void *)start + sechdr->sh_size;
+
+ fromsec = sech_name(elf, sechdr);
+ fromsec += strlen(".rel");
+ /* if from section (name) is know good then skip it */
+ if (check_section(modname, fromsec))
+ return;
+
+ for (rel = start; rel < stop; rel++) {
+ r.r_offset = TO_NATIVE(rel->r_offset);
+#if KERNEL_ELFCLASS == ELFCLASS64
+ if (elf->hdr->e_machine == EM_MIPS) {
+ unsigned int r_typ;
+ r_sym = ELF64_MIPS_R_SYM(rel->r_info);
+ r_sym = TO_NATIVE(r_sym);
+ r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
+ r.r_info = ELF64_R_INFO(r_sym, r_typ);
+ } else {
+ r.r_info = TO_NATIVE(rel->r_info);
+ r_sym = ELF_R_SYM(r.r_info);
+ }
+#else
+ r.r_info = TO_NATIVE(rel->r_info);
+ r_sym = ELF_R_SYM(r.r_info);
+#endif
+ r.r_addend = 0;
+ switch (elf->hdr->e_machine) {
+ case EM_386:
+ if (addend_386_rel(elf, sechdr, &r))
+ continue;
+ break;
+ case EM_ARM:
+ if (addend_arm_rel(elf, sechdr, &r))
+ continue;
+ break;
+ case EM_MIPS:
+ if (addend_mips_rel(elf, sechdr, &r))
+ continue;
+ break;
+ }
+ sym = elf->symtab_start + r_sym;
+ /* Skip special sections */
+ if (sym->st_shndx >= SHN_LORESERVE)
+ continue;
+ check_section_mismatch(modname, elf, &r, sym, fromsec);
+ }
+}
+
+/**
+ * A module includes a number of sections that are discarded
+ * either when loaded or when used as built-in.
+ * For loaded modules all functions marked __init and all data
+ * marked __initdata will be discarded when the module has been intialized.
+ * Likewise for modules used built-in the sections marked __exit
+ * are discarded because __exit marked function are supposed to be called
+ * only when a moduel is unloaded which never happes for built-in modules.
+ * The check_sec_ref() function traverses all relocation records
+ * to find all references to a section that reference a section that will
+ * be discarded and warns about it.
+ **/
+static void check_sec_ref(struct module *mod, const char *modname,
+ struct elf_info *elf)
+{
+ int i;
+ Elf_Shdr *sechdrs = elf->sechdrs;
+
+ /* Walk through all sections */
+ for (i = 0; i < elf->hdr->e_shnum; i++) {
+ /* We want to process only relocation sections and not .init */
+ if (sechdrs[i].sh_type == SHT_RELA)
+ section_rela(modname, elf, &elf->sechdrs[i]);
+ else if (sechdrs[i].sh_type == SHT_REL)
+ section_rel(modname, elf, &elf->sechdrs[i]);
+ }
+}
+
+static void get_markers(struct elf_info *info, struct module *mod)
+{
+ const Elf_Shdr *sh = &info->sechdrs[info->markers_strings_sec];
+ const char *strings = (const char *) info->hdr + sh->sh_offset;
+ const Elf_Sym *sym, *first_sym, *last_sym;
+ size_t n;
+
+ if (!info->markers_strings_sec)
+ return;
+
+ /*
+ * First count the strings. We look for all the symbols defined
+ * in the __markers_strings section named __mstrtab_*. For
+ * these local names, the compiler puts a random .NNN suffix on,
+ * so the names don't correspond exactly.
+ */
+ first_sym = last_sym = NULL;
+ n = 0;
+ for (sym = info->symtab_start; sym < info->symtab_stop; sym++)
+ if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT &&
+ sym->st_shndx == info->markers_strings_sec &&
+ !strncmp(info->strtab + sym->st_name,
+ "__mstrtab_", sizeof "__mstrtab_" - 1)) {
+ if (first_sym == NULL)
+ first_sym = sym;
+ last_sym = sym;
+ ++n;
+ }
+
+ if (n == 0)
+ return;
+
+ /*
+ * Now collect each name and format into a line for the output.
+ * Lines look like:
+ * marker_name vmlinux marker %s format %d
+ * The format string after the second \t can use whitespace.
+ */
+ mod->markers = NOFAIL(malloc(sizeof mod->markers[0] * n));
+ mod->nmarkers = n;
+
+ n = 0;
+ for (sym = first_sym; sym <= last_sym; sym++)
+ if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT &&
+ sym->st_shndx == info->markers_strings_sec &&
+ !strncmp(info->strtab + sym->st_name,
+ "__mstrtab_", sizeof "__mstrtab_" - 1)) {
+ const char *name = strings + sym->st_value;
+ const char *fmt = strchr(name, '\0') + 1;
+ char *line = NULL;
+ asprintf(&line, "%s\t%s\t%s\n", name, mod->name, fmt);
+ NOFAIL(line);
+ mod->markers[n++] = line;
+ }
+}
+
+static void read_symbols(char *modname)
{
const char *symname;
char *version;
+ char *license;
struct module *mod;
struct elf_info info = { };
Elf_Sym *sym;
- parse_elf(&info, modname);
+ if (!parse_elf(&info, modname))
+ return;
mod = new_module(modname);
/* When there's no vmlinux, don't print warnings about
* unresolved symbols (since there'll be too many ;) */
if (is_vmlinux(modname)) {
- unsigned int fake_crc = 0;
have_vmlinux = 1;
- add_exported_symbol("struct_module", mod, &fake_crc);
mod->skip = 1;
}
+ license = get_modinfo(info.modinfo, info.modinfo_len, "license");
+ if (!license && !is_vmlinux(modname))
+ fatal("modpost: missing MODULE_LICENSE() in %s\n"
+ "see include/linux/module.h for "
+ "more information\n", modname);
+ while (license) {
+ if (license_is_gpl_compatible(license))
+ mod->gpl_compatible = 1;
+ else {
+ mod->gpl_compatible = 0;
+ break;
+ }
+ license = get_next_modinfo(info.modinfo, info.modinfo_len,
+ "license", license);
+ }
+
for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
symname = info.strtab + sym->st_name;
handle_modversions(mod, &info, sym, symname);
handle_moddevtable(mod, &info, sym, symname);
}
+ if (!is_vmlinux(modname) ||
+ (is_vmlinux(modname) && vmlinux_section_warnings))
+ check_sec_ref(mod, modname, &info);
version = get_modinfo(info.modinfo, info.modinfo_len, "version");
if (version)
get_src_version(modname, mod->srcversion,
sizeof(mod->srcversion)-1);
+ get_markers(&info, mod);
+
parse_elf_finish(&info);
/* Our trick to get versioning for struct_module - it's
* following helper, then compare to the file on disk and
* only update the later if anything changed */
-void __attribute__((format(printf, 2, 3)))
-buf_printf(struct buffer *buf, const char *fmt, ...)
+void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
+ const char *fmt, ...)
{
char tmp[SZ];
int len;
va_list ap;
-
+
va_start(ap, fmt);
len = vsnprintf(tmp, SZ, fmt, ap);
- if (buf->size - buf->pos < len + 1) {
- buf->size += 128;
- buf->p = realloc(buf->p, buf->size);
- }
- strncpy(buf->p + buf->pos, tmp, len + 1);
- buf->pos += len;
+ buf_write(buf, tmp, len);
va_end(ap);
}
-void
-buf_write(struct buffer *buf, const char *s, int len)
+void buf_write(struct buffer *buf, const char *s, int len)
{
if (buf->size - buf->pos < len) {
- buf->size += len;
+ buf->size += len + SZ;
buf->p = realloc(buf->p, buf->size);
}
strncpy(buf->p + buf->pos, s, len);
buf->pos += len;
}
-/* Header for the generated file */
+static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
+{
+ const char *e = is_vmlinux(m) ?"":".ko";
+
+ switch (exp) {
+ case export_gpl:
+ fatal("modpost: GPL-incompatible module %s%s "
+ "uses GPL-only symbol '%s'\n", m, e, s);
+ break;
+ case export_unused_gpl:
+ fatal("modpost: GPL-incompatible module %s%s "
+ "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
+ break;
+ case export_gpl_future:
+ warn("modpost: GPL-incompatible module %s%s "
+ "uses future GPL-only symbol '%s'\n", m, e, s);
+ break;
+ case export_plain:
+ case export_unused:
+ case export_unknown:
+ /* ignore */
+ break;
+ }
+}
+
+static void check_for_unused(enum export exp, const char *m, const char *s)
+{
+ const char *e = is_vmlinux(m) ?"":".ko";
+
+ switch (exp) {
+ case export_unused:
+ case export_unused_gpl:
+ warn("modpost: module %s%s "
+ "uses symbol '%s' marked UNUSED\n", m, e, s);
+ break;
+ default:
+ /* ignore */
+ break;
+ }
+}
+
+static void check_exports(struct module *mod)
+{
+ struct symbol *s, *exp;
+
+ for (s = mod->unres; s; s = s->next) {
+ const char *basename;
+ exp = find_symbol(s->name);
+ if (!exp || exp->module == mod)
+ continue;
+ basename = strrchr(mod->name, '/');
+ if (basename)
+ basename++;
+ else
+ basename = mod->name;
+ if (!mod->gpl_compatible)
+ check_for_gpl_usage(exp->export, basename, exp->name);
+ check_for_unused(exp->export, basename, exp->name);
+ }
+}
-void
-add_header(struct buffer *b, struct module *mod)
+/**
+ * Header for the generated file
+ **/
+static void add_header(struct buffer *b, struct module *mod)
{
buf_printf(b, "#include <linux/module.h>\n");
buf_printf(b, "#include <linux/vermagic.h>\n");
buf_printf(b, "\n");
buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
buf_printf(b, "\n");
- buf_printf(b, "#undef unix\n"); /* We have a module called "unix" */
buf_printf(b, "struct module __this_module\n");
buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
- buf_printf(b, " .name = __stringify(KBUILD_MODNAME),\n");
+ buf_printf(b, " .name = KBUILD_MODNAME,\n");
if (mod->has_init)
buf_printf(b, " .init = init_module,\n");
if (mod->has_cleanup)
buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
" .exit = cleanup_module,\n"
"#endif\n");
+ buf_printf(b, " .arch = MODULE_ARCH_INIT,\n");
buf_printf(b, "};\n");
}
-/* Record CRCs for unresolved symbols */
-
-void
-add_versions(struct buffer *b, struct module *mod)
+/**
+ * Record CRCs for unresolved symbols
+ **/
+static int add_versions(struct buffer *b, struct module *mod)
{
struct symbol *s, *exp;
+ int err = 0;
for (s = mod->unres; s; s = s->next) {
exp = find_symbol(s->name);
if (!exp || exp->module == mod) {
- if (have_vmlinux && !s->weak)
- fprintf(stderr, "*** Warning: \"%s\" [%s.ko] "
- "undefined!\n", s->name, mod->name);
+ if (have_vmlinux && !s->weak) {
+ if (warn_unresolved) {
+ warn("\"%s\" [%s.ko] undefined!\n",
+ s->name, mod->name);
+ } else {
+ merror("\"%s\" [%s.ko] undefined!\n",
+ s->name, mod->name);
+ err = 1;
+ }
+ }
continue;
}
s->module = exp->module;
}
if (!modversions)
- return;
+ return err;
buf_printf(b, "\n");
buf_printf(b, "static const struct modversion_info ____versions[]\n");
- buf_printf(b, "__attribute_used__\n");
+ buf_printf(b, "__used\n");
buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n");
for (s = mod->unres; s; s = s->next) {
- if (!s->module) {
+ if (!s->module)
continue;
- }
if (!s->crc_valid) {
- fprintf(stderr, "*** Warning: \"%s\" [%s.ko] "
- "has no CRC!\n",
+ warn("\"%s\" [%s.ko] has no CRC!\n",
s->name, mod->name);
continue;
}
}
buf_printf(b, "};\n");
+
+ return err;
}
-void
-add_depends(struct buffer *b, struct module *mod, struct module *modules)
+static void add_depends(struct buffer *b, struct module *mod,
+ struct module *modules)
{
struct symbol *s;
struct module *m;
int first = 1;
- for (m = modules; m; m = m->next) {
+ for (m = modules; m; m = m->next)
m->seen = is_vmlinux(m->name);
- }
buf_printf(b, "\n");
buf_printf(b, "static const char __module_depends[]\n");
- buf_printf(b, "__attribute_used__\n");
+ buf_printf(b, "__used\n");
buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n");
buf_printf(b, "\"depends=");
for (s = mod->unres; s; s = s->next) {
+ const char *p;
if (!s->module)
continue;
continue;
s->module->seen = 1;
- buf_printf(b, "%s%s", first ? "" : ",",
- strrchr(s->module->name, '/') + 1);
+ p = strrchr(s->module->name, '/');
+ if (p)
+ p++;
+ else
+ p = s->module->name;
+ buf_printf(b, "%s%s", first ? "" : ",", p);
first = 0;
}
buf_printf(b, "\";\n");
}
-void
-add_srcversion(struct buffer *b, struct module *mod)
+static void add_srcversion(struct buffer *b, struct module *mod)
{
if (mod->srcversion[0]) {
buf_printf(b, "\n");
}
}
-void
-write_if_changed(struct buffer *b, const char *fname)
+static void write_if_changed(struct buffer *b, const char *fname)
{
char *tmp;
FILE *file;
fclose(file);
}
-void
-read_dump(const char *fname)
+/* parse Module.symvers file. line format:
+ * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
+ **/
+static void read_dump(const char *fname, unsigned int kernel)
{
unsigned long size, pos = 0;
void *file = grab_file(fname, &size);
char *line;
- if (!file)
+ if (!file)
/* No symbol versions, silently ignore */
return;
while ((line = get_next_line(&pos, file, size))) {
- char *symname, *modname, *d;
+ char *symname, *modname, *d, *export, *end;
unsigned int crc;
struct module *mod;
+ struct symbol *s;
if (!(symname = strchr(line, '\t')))
goto fail;
if (!(modname = strchr(symname, '\t')))
goto fail;
*modname++ = '\0';
- if (strchr(modname, '\t'))
- goto fail;
+ if ((export = strchr(modname, '\t')) != NULL)
+ *export++ = '\0';
+ if (export && ((end = strchr(export, '\t')) != NULL))
+ *end = '\0';
crc = strtoul(line, &d, 16);
if (*symname == '\0' || *modname == '\0' || *d != '\0')
goto fail;
-
- if (!(mod = find_module(modname))) {
- if (is_vmlinux(modname)) {
+ mod = find_module(modname);
+ if (!mod) {
+ if (is_vmlinux(modname))
have_vmlinux = 1;
- }
mod = new_module(NOFAIL(strdup(modname)));
mod->skip = 1;
}
- add_exported_symbol(symname, mod, &crc);
+ s = sym_add_exported(symname, mod, export_no(export));
+ s->kernel = kernel;
+ s->preloaded = 1;
+ sym_update_crc(symname, mod, crc, export_no(export));
}
return;
fail:
fatal("parse error in symbol dump file\n");
}
-void
-write_dump(const char *fname)
+/* For normal builds always dump all symbols.
+ * For external modules only dump symbols
+ * that are not read from kernel Module.symvers.
+ **/
+static int dump_sym(struct symbol *sym)
+{
+ if (!external_module)
+ return 1;
+ if (sym->vmlinux || sym->kernel)
+ return 0;
+ return 1;
+}
+
+static void write_dump(const char *fname)
{
struct buffer buf = { };
struct symbol *symbol;
for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
symbol = symbolhash[n];
while (symbol) {
+ if (dump_sym(symbol))
+ buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
+ symbol->crc, symbol->name,
+ symbol->module->name,
+ export_str(symbol->export));
symbol = symbol->next;
}
}
+ write_if_changed(&buf, fname);
+}
- for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
- symbol = symbolhash[n];
- while (symbol) {
- buf_printf(&buf, "0x%08x\t%s\t%s\n", symbol->crc,
- symbol->name, symbol->module->name);
- symbol = symbol->next;
+static void add_marker(struct module *mod, const char *name, const char *fmt)
+{
+ char *line = NULL;
+ asprintf(&line, "%s\t%s\t%s\n", name, mod->name, fmt);
+ NOFAIL(line);
+
+ mod->markers = NOFAIL(realloc(mod->markers, ((mod->nmarkers + 1) *
+ sizeof mod->markers[0])));
+ mod->markers[mod->nmarkers++] = line;
+}
+
+static void read_markers(const char *fname)
+{
+ unsigned long size, pos = 0;
+ void *file = grab_file(fname, &size);
+ char *line;
+
+ if (!file) /* No old markers, silently ignore */
+ return;
+
+ while ((line = get_next_line(&pos, file, size))) {
+ char *marker, *modname, *fmt;
+ struct module *mod;
+
+ marker = line;
+ modname = strchr(marker, '\t');
+ if (!modname)
+ goto fail;
+ *modname++ = '\0';
+ fmt = strchr(modname, '\t');
+ if (!fmt)
+ goto fail;
+ *fmt++ = '\0';
+ if (*marker == '\0' || *modname == '\0')
+ goto fail;
+
+ mod = find_module(modname);
+ if (!mod) {
+ if (is_vmlinux(modname))
+ have_vmlinux = 1;
+ mod = new_module(NOFAIL(strdup(modname)));
+ mod->skip = 1;
}
+
+ add_marker(mod, marker, fmt);
}
+ return;
+fail:
+ fatal("parse error in markers list file\n");
+}
+
+static int compare_strings(const void *a, const void *b)
+{
+ return strcmp(*(const char **) a, *(const char **) b);
+}
+
+static void write_markers(const char *fname)
+{
+ struct buffer buf = { };
+ struct module *mod;
+ size_t i;
+
+ for (mod = modules; mod; mod = mod->next)
+ if ((!external_module || !mod->skip) && mod->markers != NULL) {
+ /*
+ * Sort the strings so we can skip duplicates when
+ * we write them out.
+ */
+ qsort(mod->markers, mod->nmarkers,
+ sizeof mod->markers[0], &compare_strings);
+ for (i = 0; i < mod->nmarkers; ++i) {
+ char *line = mod->markers[i];
+ buf_write(&buf, line, strlen(line));
+ while (i + 1 < mod->nmarkers &&
+ !strcmp(mod->markers[i],
+ mod->markers[i + 1]))
+ free(mod->markers[i++]);
+ free(mod->markers[i]);
+ }
+ free(mod->markers);
+ mod->markers = NULL;
+ }
+
write_if_changed(&buf, fname);
}
-int
-main(int argc, char **argv)
+struct ext_sym_list {
+ struct ext_sym_list *next;
+ const char *file;
+};
+
+int main(int argc, char **argv)
{
struct module *mod;
struct buffer buf = { };
- char fname[SZ];
- char *dump_read = NULL, *dump_write = NULL;
+ char *kernel_read = NULL, *module_read = NULL;
+ char *dump_write = NULL;
+ char *markers_read = NULL;
+ char *markers_write = NULL;
int opt;
-
- while ((opt = getopt(argc, argv, "i:mo:a")) != -1) {
- switch(opt) {
- case 'i':
- dump_read = optarg;
- break;
- case 'm':
- modversions = 1;
- break;
- case 'o':
- dump_write = optarg;
+ int err;
+ struct ext_sym_list *extsym_iter;
+ struct ext_sym_list *extsym_start = NULL;
+
+ while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) {
+ switch (opt) {
+ case 'i':
+ kernel_read = optarg;
+ break;
+ case 'I':
+ module_read = optarg;
+ external_module = 1;
+ break;
+ case 'c':
+ cross_build = 1;
+ break;
+ case 'e':
+ external_module = 1;
+ extsym_iter =
+ NOFAIL(malloc(sizeof(*extsym_iter)));
+ extsym_iter->next = extsym_start;
+ extsym_iter->file = optarg;
+ extsym_start = extsym_iter;
+ break;
+ case 'm':
+ modversions = 1;
+ break;
+ case 'o':
+ dump_write = optarg;
+ break;
+ case 'a':
+ all_versions = 1;
+ break;
+ case 's':
+ vmlinux_section_warnings = 0;
+ break;
+ case 'S':
+ sec_mismatch_verbose = 0;
+ break;
+ case 'w':
+ warn_unresolved = 1;
+ break;
+ case 'M':
+ markers_write = optarg;
break;
- case 'a':
- all_versions = 1;
+ case 'K':
+ markers_read = optarg;
break;
- default:
- exit(1);
+ default:
+ exit(1);
}
}
- if (dump_read)
- read_dump(dump_read);
+ if (kernel_read)
+ read_dump(kernel_read, 1);
+ if (module_read)
+ read_dump(module_read, 0);
+ while (extsym_start) {
+ read_dump(extsym_start->file, 0);
+ extsym_iter = extsym_start->next;
+ free(extsym_start);
+ extsym_start = extsym_iter;
+ }
- while (optind < argc) {
+ while (optind < argc)
read_symbols(argv[optind++]);
+
+ for (mod = modules; mod; mod = mod->next) {
+ if (mod->skip)
+ continue;
+ check_exports(mod);
}
+ err = 0;
+
for (mod = modules; mod; mod = mod->next) {
+ char fname[strlen(mod->name) + 10];
+
if (mod->skip)
continue;
buf.pos = 0;
add_header(&buf, mod);
- add_versions(&buf, mod);
+ err |= add_versions(&buf, mod);
add_depends(&buf, mod, modules);
add_moddevtable(&buf, mod);
add_srcversion(&buf, mod);
if (dump_write)
write_dump(dump_write);
+ if (sec_mismatch_count && !sec_mismatch_verbose)
+ warn("modpost: Found %d section mismatch(es).\n"
+ "To see full details build your kernel with:\n"
+ "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n",
+ sec_mismatch_count);
- return 0;
-}
+ if (markers_read)
+ read_markers(markers_read);
+
+ if (markers_write)
+ write_markers(markers_write);
+ return err;
+}