*
* Copyright 2003 Kai Germaschewski
* Copyright 2002-2004 Rusty Russell, IBM Corporation
- *
+ * Copyright 2006 Sam Ravnborg
* Based in part on module-init-tools/depmod.c,file2alias
*
* This software may be used and distributed according to the terms
#include <ctype.h>
#include "modpost.h"
+#include "../../include/linux/license.h"
/* Are we using CONFIG_MODVERSIONS? */
int modversions = 0;
static int all_versions = 0;
/* If we are modposting external module set to 1 */
static int external_module = 0;
+/* Only warn about unresolved symbols */
+static int warn_unresolved = 0;
+/* How a symbol is exported */
+enum export {
+ export_plain, export_unused, export_gpl,
+ export_unused_gpl, export_gpl_future, export_unknown
+};
void fatal(const char *fmt, ...)
{
va_end(arglist);
}
+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;
{
struct module *mod;
char *p, *s;
-
+
mod = NOFAIL(malloc(sizeof(*mod)));
memset(mod, 0, sizeof(*mod));
p = NOFAIL(strdup(modname));
/* add to list */
mod->name = p;
+ mod->gpl_compatible = -1;
mod->next = modules;
modules = mod;
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];
};
}
/* For the hash of exported symbols */
-static struct symbol *new_symbol(const char *name, struct module *module)
+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;
+ new->export = export;
return new;
}
return NULL;
}
+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)
+static struct symbol *sym_add_exported(const char *name, struct module *mod,
+ enum export export)
{
struct symbol *s = find_symbol(name);
- if (!s)
- s = new_symbol(name, mod);
-
+ if (!s) {
+ 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");
+ }
+ }
+ 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)
+ unsigned int crc, enum export export)
{
struct symbol *s = find_symbol(name);
if (!s)
- s = new_symbol(name, mod);
+ s = new_symbol(name, mod, export);
s->crc = crc;
s->crc_valid = 1;
}
munmap(file, size);
}
-static 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;
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;
+ const char *secname;
- if (sechdrs[i].sh_offset > info->size)
- goto truncated;
- if (strcmp(secstrings+sechdrs[i].sh_name, ".modinfo") == 0) {
+ if (sechdrs[i].sh_offset > info->size) {
+ fatal("%s is truncated. sechdrs[i].sh_offset=%u > sizeof(*hrd)=%ul\n", filename, (unsigned int)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;
+
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) {
sym->st_value = TO_NATIVE(sym->st_value);
sym->st_size = TO_NATIVE(sym->st_size);
}
- return;
-
- truncated:
- fatal("%s is truncated.\n", filename);
+ return 1;
}
static void parse_elf_finish(struct elf_info *info)
release_file(info->hdr, info->size);
}
-#define CRC_PFX "__crc_"
-#define KSYMTAB_PFX "__ksymtab_"
+#define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_"
+#define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
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:
/* CRC'd symbol */
if (memcmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
crc = (unsigned int) sym->st_value;
- sym_update_crc(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 +
default:
/* All exported symbols */
if (memcmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
- sym_add_exported(symname + strlen(KSYMTAB_PFX), mod);
+ sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
+ export);
}
if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
mod->has_init = 1;
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;
}
+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);
+}
+
+/**
+ * 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.text | .exit.text | .init.data
+ * fromsec = .data
+ * atsym = *driver, *_template, *_sht, *_ops, *_probe, *probe_one, *_console
+ *
+ * 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
+ *
+ * Pattern 5:
+ * Logos used in drivers/video/logo reside in __initdata but the
+ * funtion that references them are EXPORT_SYMBOL() so cannot be
+ * marker __init. So we whitelist them here.
+ * The pattern is:
+ * tosec = .init.data
+ * fromsec = .text*
+ * refsymname = logo_
+ **/
+static int secref_whitelist(const char *modname, const char *tosec,
+ const char *fromsec, const char *atsym,
+ const char *refsymname)
+{
+ int f1 = 1, f2 = 1;
+ const char **s;
+ const char *pat2sym[] = {
+ "driver",
+ "_template", /* scsi uses *_template a lot */
+ "_sht", /* scsi also used *_sht to some extent */
+ "_ops",
+ "_probe",
+ "_probe_one",
+ "_console",
+ NULL
+ };
+
+ const char *pat3refsym[] = {
+ "__init_begin",
+ "_sinittext",
+ "_einittext",
+ NULL
+ };
+
+ /* Check for pattern 0 */
+ if ((strcmp(fromsec, ".text.init.refok") == 0) ||
+ (strcmp(fromsec, ".data.init.refok") == 0))
+ return 1;
+
+ /* Check for pattern 1 */
+ if (strcmp(tosec, ".init.data") != 0)
+ f1 = 0;
+ if (strncmp(fromsec, ".data", strlen(".data")) != 0)
+ f1 = 0;
+ if (strncmp(atsym, "__param", strlen("__param")) != 0)
+ f1 = 0;
+
+ if (f1)
+ return f1;
+
+ /* Check for pattern 2 */
+ if ((strcmp(tosec, ".init.text") != 0) &&
+ (strcmp(tosec, ".exit.text") != 0) &&
+ (strcmp(tosec, ".init.data") != 0))
+ f2 = 0;
+ if (strcmp(fromsec, ".data") != 0)
+ f2 = 0;
+
+ for (s = pat2sym; *s; s++)
+ if (strrcmp(atsym, *s) == 0)
+ f1 = 1;
+ if (f1 && f2)
+ return 1;
+
+ /* Check for pattern 3 */
+ if ((strcmp(fromsec, ".text.head") == 0) &&
+ ((strcmp(tosec, ".init.data") == 0) ||
+ (strcmp(tosec, ".init.text") == 0)))
+ return 1;
+
+ /* Check for pattern 4 */
+ for (s = pat3refsym; *s; s++)
+ if (strcmp(refsymname, *s) == 0)
+ return 1;
+
+ /* Check for pattern 5 */
+ if ((strcmp(tosec, ".init.data") == 0) &&
+ (strncmp(fromsec, ".text", strlen(".text")) == 0) &&
+ (strncmp(refsymname, "logo_", strlen("logo_")) == 0))
+ return 1;
+
+ return 0;
+}
+
+/**
+ * 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, Elf_Addr addr,
+ Elf_Sym *relsym)
+{
+ Elf_Sym *sym;
+
+ 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;
+ }
+ 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 void find_symbols_between(struct elf_info *elf, Elf_Addr addr,
+ const char *sec,
+ Elf_Sym **before, Elf_Sym **after)
+{
+ Elf_Sym *sym;
+ Elf_Ehdr *hdr = elf->hdr;
+ Elf_Addr beforediff = ~0;
+ Elf_Addr afterdiff = ~0;
+ const char *secstrings = (void *)hdr +
+ elf->sechdrs[hdr->e_shstrndx].sh_offset;
+
+ *before = NULL;
+ *after = NULL;
+
+ for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
+ const char *symsec;
+
+ if (sym->st_shndx >= SHN_LORESERVE)
+ continue;
+ symsec = secstrings + elf->sechdrs[sym->st_shndx].sh_name;
+ if (strcmp(symsec, sec) != 0)
+ continue;
+ if (!is_valid_name(elf, sym))
+ continue;
+ if (sym->st_value <= addr) {
+ if ((addr - sym->st_value) < beforediff) {
+ beforediff = addr - sym->st_value;
+ *before = sym;
+ }
+ else if ((addr - sym->st_value) == beforediff) {
+ *before = sym;
+ }
+ }
+ else
+ {
+ if ((sym->st_value - addr) < afterdiff) {
+ afterdiff = sym->st_value - addr;
+ *after = sym;
+ }
+ else if ((sym->st_value - addr) == afterdiff) {
+ *after = sym;
+ }
+ }
+ }
+}
+
+/**
+ * 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 warn_sec_mismatch(const char *modname, const char *fromsec,
+ struct elf_info *elf, Elf_Sym *sym, Elf_Rela r)
+{
+ const char *refsymname = "";
+ Elf_Sym *before, *after;
+ Elf_Sym *refsym;
+ Elf_Ehdr *hdr = elf->hdr;
+ Elf_Shdr *sechdrs = elf->sechdrs;
+ const char *secstrings = (void *)hdr +
+ sechdrs[hdr->e_shstrndx].sh_offset;
+ const char *secname = secstrings + sechdrs[sym->st_shndx].sh_name;
+
+ find_symbols_between(elf, r.r_offset, fromsec, &before, &after);
+
+ refsym = find_elf_symbol(elf, r.r_addend, sym);
+ if (refsym && strlen(elf->strtab + refsym->st_name))
+ refsymname = elf->strtab + refsym->st_name;
+
+ /* check whitelist - we may ignore it */
+ if (before &&
+ secref_whitelist(modname, secname, fromsec,
+ elf->strtab + before->st_name, refsymname))
+ return;
+
+ if (before && after) {
+ warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
+ "(between '%s' and '%s')\n",
+ modname, fromsec, (unsigned long long)r.r_offset,
+ secname, refsymname,
+ elf->strtab + before->st_name,
+ elf->strtab + after->st_name);
+ } else if (before) {
+ warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
+ "(after '%s')\n",
+ modname, fromsec, (unsigned long long)r.r_offset,
+ secname, refsymname,
+ elf->strtab + before->st_name);
+ } else if (after) {
+ warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
+ "before '%s' (at offset -0x%llx)\n",
+ modname, fromsec, (unsigned long long)r.r_offset,
+ secname, refsymname,
+ elf->strtab + after->st_name);
+ } else {
+ warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s\n",
+ modname, fromsec, (unsigned long long)r.r_offset,
+ secname, refsymname);
+ }
+}
+
+static unsigned int *reloc_location(struct elf_info *elf,
+ int rsection, Elf_Rela *r)
+{
+ Elf_Shdr *sechdrs = elf->sechdrs;
+ int section = sechdrs[rsection].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, int rsection, Elf_Rela *r)
+{
+ unsigned int r_typ = ELF_R_TYPE(r->r_info);
+ unsigned int *location = reloc_location(elf, rsection, 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, int rsection, 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 + elf->sechdrs[rsection].sh_offset +
+ (r->r_offset - elf->sechdrs[rsection].sh_addr));
+ break;
+ default:
+ return 1;
+ }
+ return 0;
+}
+
+static int addend_mips_rel(struct elf_info *elf, int rsection, Elf_Rela *r)
+{
+ unsigned int r_typ = ELF_R_TYPE(r->r_info);
+ unsigned int *location = reloc_location(elf, rsection, 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;
+}
+
+/**
+ * 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 section(const char*),
+ int section_ref_ok(const char *))
+{
+ int i;
+ Elf_Sym *sym;
+ Elf_Ehdr *hdr = elf->hdr;
+ Elf_Shdr *sechdrs = elf->sechdrs;
+ const char *secstrings = (void *)hdr +
+ sechdrs[hdr->e_shstrndx].sh_offset;
+
+ /* Walk through all sections */
+ for (i = 0; i < hdr->e_shnum; i++) {
+ const char *name = secstrings + sechdrs[i].sh_name;
+ const char *secname;
+ Elf_Rela r;
+ unsigned int r_sym;
+ /* We want to process only relocation sections and not .init */
+ if (sechdrs[i].sh_type == SHT_RELA) {
+ Elf_Rela *rela;
+ Elf_Rela *start = (void *)hdr + sechdrs[i].sh_offset;
+ Elf_Rela *stop = (void*)start + sechdrs[i].sh_size;
+ name += strlen(".rela");
+ if (section_ref_ok(name))
+ continue;
+
+ for (rela = start; rela < stop; rela++) {
+ r.r_offset = TO_NATIVE(rela->r_offset);
+#if KERNEL_ELFCLASS == ELFCLASS64
+ if (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;
+
+ secname = secstrings +
+ sechdrs[sym->st_shndx].sh_name;
+ if (section(secname))
+ warn_sec_mismatch(modname, name,
+ elf, sym, r);
+ }
+ } else if (sechdrs[i].sh_type == SHT_REL) {
+ Elf_Rel *rel;
+ Elf_Rel *start = (void *)hdr + sechdrs[i].sh_offset;
+ Elf_Rel *stop = (void*)start + sechdrs[i].sh_size;
+ name += strlen(".rel");
+ if (section_ref_ok(name))
+ continue;
+
+ for (rel = start; rel < stop; rel++) {
+ r.r_offset = TO_NATIVE(rel->r_offset);
+#if KERNEL_ELFCLASS == ELFCLASS64
+ if (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 (hdr->e_machine) {
+ case EM_386:
+ if (addend_386_rel(elf, i, &r))
+ continue;
+ break;
+ case EM_ARM:
+ if(addend_arm_rel(elf, i, &r))
+ continue;
+ break;
+ case EM_MIPS:
+ if (addend_mips_rel(elf, i, &r))
+ continue;
+ break;
+ }
+ sym = elf->symtab_start + r_sym;
+ /* Skip special sections */
+ if (sym->st_shndx >= SHN_LORESERVE)
+ continue;
+
+ secname = secstrings +
+ sechdrs[sym->st_shndx].sh_name;
+ if (section(secname))
+ warn_sec_mismatch(modname, name,
+ elf, sym, r);
+ }
+ }
+ }
+}
+
+/*
+ * Identify sections from which references to either a
+ * .init or a .exit section is OK.
+ *
+ * [OPD] Keith Ownes <kaos@sgi.com> commented:
+ * For our future {in}sanity, add a comment that this is the ppc .opd
+ * section, not the ia64 .opd section.
+ * ia64 .opd should not point to discarded sections.
+ * [.rodata] like for .init.text we ignore .rodata references -same reason
+ */
+static int initexit_section_ref_ok(const char *name)
+{
+ const char **s;
+ /* Absolute section names */
+ const char *namelist1[] = {
+ "__bug_table", /* used by powerpc for BUG() */
+ "__ex_table",
+ ".altinstructions",
+ ".cranges", /* used by sh64 */
+ ".fixup",
+ ".machvec", /* ia64 + powerpc uses these */
+ ".machine.desc",
+ ".opd", /* See comment [OPD] */
+ ".parainstructions",
+ ".pdr",
+ ".plt", /* seen on ARCH=um build on x86_64. Harmless */
+ ".smp_locks",
+ ".stab",
+ NULL
+ };
+ /* Start of section names */
+ const char *namelist2[] = {
+ ".debug",
+ ".eh_frame",
+ ".note", /* ignore ELF notes - may contain anything */
+ ".got", /* powerpc - global offset table */
+ ".toc", /* powerpc - table of contents */
+ NULL
+ };
+ /* part of section name */
+ const char *namelist3 [] = {
+ ".unwind", /* Sample: IA_64.unwind.exit.text */
+ NULL
+ };
+
+ for (s = namelist1; *s; s++)
+ if (strcmp(*s, name) == 0)
+ return 1;
+ for (s = namelist2; *s; s++)
+ if (strncmp(*s, name, strlen(*s)) == 0)
+ return 1;
+ for (s = namelist3; *s; s++)
+ if (strstr(name, *s) != NULL)
+ return 1;
+ return 0;
+}
+
+/**
+ * Functions used only during module init is marked __init and is stored in
+ * a .init.text section. Likewise data is marked __initdata and stored in
+ * a .init.data section.
+ * If this section is one of these sections return 1
+ * See include/linux/init.h for the details
+ **/
+static int init_section(const char *name)
+{
+ if (strcmp(name, ".init") == 0)
+ return 1;
+ if (strncmp(name, ".init.", strlen(".init.")) == 0)
+ return 1;
+ return 0;
+}
+
+/*
+ * Identify sections from which references to a .init section is OK.
+ *
+ * Unfortunately references to read only data that referenced .init
+ * sections had to be excluded. Almost all of these are false
+ * positives, they are created by gcc. The downside of excluding rodata
+ * is that there really are some user references from rodata to
+ * init code, e.g. drivers/video/vgacon.c:
+ *
+ * const struct consw vga_con = {
+ * con_startup: vgacon_startup,
+ *
+ * where vgacon_startup is __init. If you want to wade through the false
+ * positives, take out the check for rodata.
+ */
+static int init_section_ref_ok(const char *name)
+{
+ const char **s;
+ /* Absolute section names */
+ const char *namelist1[] = {
+ "__ftr_fixup", /* powerpc cpu feature fixup */
+ "__fw_ftr_fixup", /* powerpc firmware feature fixup */
+ "__param",
+ ".data.rel.ro", /* used by parisc64 */
+ ".init",
+ ".text.lock",
+ NULL
+ };
+ /* Start of section names */
+ const char *namelist2[] = {
+ ".init.",
+ ".pci_fixup",
+ ".rodata",
+ NULL
+ };
+
+ if (initexit_section_ref_ok(name))
+ return 1;
+
+ for (s = namelist1; *s; s++)
+ if (strcmp(*s, name) == 0)
+ return 1;
+ for (s = namelist2; *s; s++)
+ if (strncmp(*s, name, strlen(*s)) == 0)
+ return 1;
+
+ /* If section name ends with ".init" we allow references
+ * as is the case with .initcallN.init, .early_param.init, .taglist.init etc
+ */
+ if (strrcmp(name, ".init") == 0)
+ return 1;
+ return 0;
+}
+
+/*
+ * Functions used only during module exit is marked __exit and is stored in
+ * a .exit.text section. Likewise data is marked __exitdata and stored in
+ * a .exit.data section.
+ * If this section is one of these sections return 1
+ * See include/linux/init.h for the details
+ **/
+static int exit_section(const char *name)
+{
+ if (strcmp(name, ".exit.text") == 0)
+ return 1;
+ if (strcmp(name, ".exit.data") == 0)
+ return 1;
+ return 0;
+
+}
+
+/*
+ * Identify sections from which references to a .exit section is OK.
+ */
+static int exit_section_ref_ok(const char *name)
+{
+ const char **s;
+ /* Absolute section names */
+ const char *namelist1[] = {
+ ".exit.data",
+ ".exit.text",
+ ".exitcall.exit",
+ ".rodata",
+ NULL
+ };
+
+ if (initexit_section_ref_ok(name))
+ return 1;
+
+ for (s = namelist1; *s; s++)
+ if (strcmp(*s, name) == 0)
+ return 1;
+ return 0;
+}
+
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);
mod->skip = 1;
}
+ license = get_modinfo(info.modinfo, info.modinfo_len, "license");
+ 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);
}
+ check_sec_ref(mod, modname, &info, init_section, init_section_ref_ok);
+ check_sec_ref(mod, modname, &info, exit_section, exit_section_ref_ok);
version = get_modinfo(info.modinfo, info.modinfo_len, "version");
if (version)
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)
{
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;
}
+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);
+ }
+}
+
/**
* Header for the generated file
**/
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
**/
-static void add_versions(struct buffer *b, struct module *mod)
+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)
- warn("\"%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, "};\n");
+
+ return err;
}
static void add_depends(struct buffer *b, struct module *mod,
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);
+ if ((p = strrchr(s->module->name, '/')) != NULL)
+ p++;
+ else
+ p = s->module->name;
+ buf_printf(b, "%s%s", first ? "" : ",", p);
first = 0;
}
buf_printf(b, "\";\n");
fclose(file);
}
+/* 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;
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 (!(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;
mod = new_module(NOFAIL(strdup(modname)));
mod->skip = 1;
}
- s = sym_add_exported(symname, mod);
- s->kernel = kernel;
- sym_update_crc(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:
return 0;
return 1;
}
-
+
static void write_dump(const char *fname)
{
struct buffer buf = { };
symbol = symbolhash[n];
while (symbol) {
if (dump_sym(symbol))
- buf_printf(&buf, "0x%08x\t%s\t%s\n",
- symbol->crc, symbol->name,
- symbol->module->name);
+ 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;
}
}
char *kernel_read = NULL, *module_read = NULL;
char *dump_write = NULL;
int opt;
+ int err;
- while ((opt = getopt(argc, argv, "i:I:mo:a")) != -1) {
+ while ((opt = getopt(argc, argv, "i:I:mo:aw")) != -1) {
switch(opt) {
case 'i':
kernel_read = optarg;
case 'a':
all_versions = 1;
break;
+ case 'w':
+ warn_unresolved = 1;
+ break;
default:
exit(1);
}
for (mod = modules; mod; mod = mod->next) {
if (mod->skip)
continue;
+ check_exports(mod);
+ }
+
+ err = 0;
+
+ for (mod = modules; mod; mod = mod->next) {
+ 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);
- return 0;
+ return err;
}