/* Postprocess module symbol versions
*
* Copyright 2003 Kai Germaschewski
- * 2002-2003 Rusty Russell, IBM Corporation
- *
+ * 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;
/* Warn about undefined symbols? (do so if we have vmlinux) */
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;
+/* 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, ...)
+void fatal(const char *fmt, ...)
{
va_list arglist;
exit(1);
}
-void
-warn(const char *fmt, ...)
+void warn(const char *fmt, ...)
{
va_list arglist;
va_end(arglist);
}
-void *do_nofail(void *ptr, const char *file, int line, const char *expr)
+static int is_vmlinux(const char *modname)
+{
+ const char *myname;
+
+ if ((myname = strrchr(modname, '/')))
+ myname++;
+ else
+ myname = modname;
+
+ return strcmp(myname, "vmlinux") == 0;
+}
+
+void *do_nofail(void *ptr, const char *expr)
{
if (!ptr) {
- fatal("Memory allocation failure %s line %d: %s.\n",
- file, line, expr);
+ fatal("modpost: Memory allocation failure: %s.\n", expr);
}
return ptr;
}
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));
/* add to list */
mod->name = p;
+ mod->gpl_compatible = -1;
mod->next = modules;
modules = mod;
struct module *module;
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];
};
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, 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));
memset(s, 0, sizeof(*s));
strcpy(s->name, name);
+ s->weak = weak;
s->next = next;
return s;
}
/* 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, symbolhash[hash]);
+ 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;
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");
+ }
}
+ s->preloaded = 0;
+ s->vmlinux = is_vmlinux(mod->name);
+ s->kernel = 0;
+ s->export = export;
+ return s;
}
-void *
-grab_file(const char *filename, unsigned long *size)
+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)
{
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;
size_t len = 0;
- char *p = (char *)file + *pos;
+ signed char *p = (signed char *)file + *pos;
char *s = line;
for (; *pos < size ; (*pos)++)
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 void parse_elf(struct elf_info *info, const char *filename)
{
unsigned int i;
Elf_Ehdr *hdr = info->hdr;
hdr = grab_file(filename, &info->size);
if (!hdr) {
perror(filename);
- abort();
+ exit(1);
}
info->hdr = hdr;
if (info->size < sizeof(*hdr))
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) {
+ 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) {
- fprintf(stderr, "modpost: %s no symtab?\n", filename);
- abort();
+ fatal("%s has no symtab?\n", filename);
}
/* Fix endianness in symbols */
for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
return;
truncated:
- fprintf(stderr, "modpost: %s is truncated.\n", filename);
- abort();
+ fatal("%s is truncated.\n", filename);
}
-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);
- modversions = 1;
+ sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
+ export);
}
break;
case SHN_UNDEF:
/* undefined symbol */
- if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL)
+ if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
+ ELF_ST_BIND(sym->st_info) != STB_WEAK)
break;
/* ignore global offset table */
if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
/* ignore __this_module, it will be resolved shortly */
if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0)
break;
-#ifdef STT_REGISTER
+/* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
+#if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
+/* add compatibility with older glibc */
+#ifndef STT_SPARC_REGISTER
+#define STT_SPARC_REGISTER STT_REGISTER
+#endif
if (info->hdr->e_machine == EM_SPARC ||
info->hdr->e_machine == EM_SPARCV9) {
/* Ignore register directives. */
- if (ELF_ST_TYPE(sym->st_info) == STT_REGISTER)
+ 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;
+ }
}
#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);
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;
+ if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0)
+ mod->has_cleanup = 1;
break;
}
}
-int
-is_vmlinux(const char *modname)
+/**
+ * Parse tag=value strings from .modinfo section
+ **/
+static char *next_string(char *string, unsigned long *secsize)
{
- const char *myname;
+ /* Skip non-zero chars */
+ while (string[0]) {
+ string++;
+ if ((*secsize)-- <= 1)
+ return NULL;
+ }
- if ((myname = strrchr(modname, '/')))
- myname++;
- else
- myname = modname;
+ /* Skip any zero padding. */
+ while (!string[0]) {
+ string++;
+ if ((*secsize)-- <= 1)
+ return NULL;
+ }
+ return string;
+}
- return strcmp(myname, "vmlinux") == 0;
+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 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
+ *
+ * Pattern 3:
+ * 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 *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 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;
+
+ /* Whitelist all references from .pci_fixup section if vmlinux */
+ if (is_vmlinux(modname)) {
+ if ((strcmp(fromsec, ".pci_fixup") == 0) &&
+ (strcmp(tosec, ".init.text") == 0))
+ return 1;
+
+ /* Check for pattern 3 */
+ for (s = pat3refsym; *s; s++)
+ if (strcmp(refsymname, *s) == 0)
+ return 1;
+ }
+ return 0;
}
-void
-read_symbols(char *modname)
+/**
+ * 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 (sym->st_value == addr)
+ return sym;
+ }
+ return NULL;
+}
+
+/*
+ * 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 (sym->st_value <= addr) {
+ if ((addr - sym->st_value) < beforediff) {
+ beforediff = addr - sym->st_value;
+ *before = sym;
+ }
+ else if ((addr - sym->st_value) == beforediff) {
+ /* equal offset, valid name? */
+ const char *name = elf->strtab + sym->st_name;
+ if (name && strlen(name))
+ *before = sym;
+ }
+ }
+ else
+ {
+ if ((sym->st_value - addr) < afterdiff) {
+ afterdiff = sym->st_value - addr;
+ *after = sym;
+ }
+ else if ((sym->st_value - addr) == afterdiff) {
+ /* equal offset, valid name? */
+ const char *name = elf->strtab + sym->st_name;
+ if (name && strlen(name))
+ *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 - Section mismatch: reference to %s:%s from %s "
+ "between '%s' (at offset 0x%llx) and '%s'\n",
+ modname, secname, refsymname, fromsec,
+ elf->strtab + before->st_name,
+ (long long)r.r_offset,
+ elf->strtab + after->st_name);
+ } else if (before) {
+ warn("%s - Section mismatch: reference to %s:%s from %s "
+ "after '%s' (at offset 0x%llx)\n",
+ modname, secname, refsymname, fromsec,
+ elf->strtab + before->st_name,
+ (long long)r.r_offset);
+ } else if (after) {
+ warn("%s - Section mismatch: reference to %s:%s from %s "
+ "before '%s' (at offset -0x%llx)\n",
+ modname, secname, refsymname, fromsec,
+ elf->strtab + after->st_name,
+ (long long)r.r_offset);
+ } else {
+ warn("%s - Section mismatch: reference to %s:%s from %s "
+ "(offset 0x%llx)\n",
+ modname, secname, fromsec, refsymname,
+ (long long)r.r_offset);
+ }
+}
+
+/**
+ * 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) {
+ r_sym = ELF64_MIPS_R_SYM(rela->r_info);
+ r_sym = TO_NATIVE(r_sym);
+ } 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) {
+ r_sym = ELF64_MIPS_R_SYM(rel->r_info);
+ r_sym = TO_NATIVE(r_sym);
+ } 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;
+ 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);
+ }
+ }
+ }
+}
+
+/**
+ * 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[] = {
+ ".init",
+ ".opd", /* see comment [OPD] at exit_section_ref_ok() */
+ ".toc1", /* used by ppc64 */
+ ".stab",
+ ".rodata",
+ ".parainstructions",
+ ".text.lock",
+ "__bug_table", /* used by powerpc for BUG() */
+ ".pci_fixup_header",
+ ".pci_fixup_final",
+ ".pdr",
+ "__param",
+ "__ex_table",
+ ".fixup",
+ ".smp_locks",
+ ".plt", /* seen on ARCH=um build on x86_64. Harmless */
+ "__ftr_fixup", /* powerpc cpu feature fixup */
+ "__fw_ftr_fixup", /* powerpc firmware feature fixup */
+ NULL
+ };
+ /* Start of section names */
+ const char *namelist2[] = {
+ ".init.",
+ ".altinstructions",
+ ".eh_frame",
+ ".debug",
+ ".parainstructions",
+ NULL
+ };
+ /* part of section name */
+ const char *namelist3 [] = {
+ ".unwind", /* sample: IA_64.unwind.init.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;
+ 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.
+ *
+ * [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 exit_section_ref_ok(const char *name)
+{
+ const char **s;
+ /* Absolute section names */
+ const char *namelist1[] = {
+ ".exit.text",
+ ".exit.data",
+ ".init.text",
+ ".rodata",
+ ".opd", /* See comment [OPD] */
+ ".toc1", /* used by ppc64 */
+ ".altinstructions",
+ ".pdr",
+ "__bug_table", /* used by powerpc for BUG() */
+ ".exitcall.exit",
+ ".eh_frame",
+ ".parainstructions",
+ ".stab",
+ "__ex_table",
+ ".fixup",
+ ".smp_locks",
+ ".plt", /* seen on ARCH=um build on x86_64. Harmless */
+ NULL
+ };
+ /* Start of section names */
+ const char *namelist2[] = {
+ ".debug",
+ 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;
+}
+
+static void read_symbols(char *modname)
{
const char *symname;
+ char *version;
+ char *license;
struct module *mod;
struct elf_info info = { };
Elf_Sym *sym;
/* 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;
- /* May not have this if !CONFIG_MODULE_UNLOAD: fake it.
- If it appears, we'll get the real CRC. */
- add_exported_symbol("cleanup_module", mod, &fake_crc);
- add_exported_symbol("struct_module", mod, &fake_crc);
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);
}
- maybe_frob_version(modname, info.modinfo, info.modinfo_len,
- (void *)info.modinfo - (void *)info.hdr);
+ 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)
+ maybe_frob_rcs_version(modname, version, info.modinfo,
+ version - (char *)info.hdr);
+ if (version || (all_versions && !is_vmlinux(modname)))
+ get_src_version(modname, mod->srcversion,
+ sizeof(mod->srcversion)-1);
+
parse_elf_finish(&info);
/* Our trick to get versioning for struct_module - it's
* never passed as an argument to an exported function, so
* the automatic versioning doesn't pick it up, but it's really
* important anyhow */
- if (modversions) {
- mod->unres = alloc_symbol("struct_module", mod->unres);
-
- /* Always version init_module and cleanup_module, in
- * case module doesn't have its own. */
- mod->unres = alloc_symbol("init_module", mod->unres);
- mod->unres = alloc_symbol("cleanup_module", mod->unres);
- }
+ if (modversions)
+ mod->unres = alloc_symbol("struct_module", 0, mod->unres);
}
#define SZ 500
* 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;
+ }
+}
-void
-add_header(struct buffer *b)
+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
+ **/
+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, " .init = init_module,\n");
- buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n");
- buf_printf(b, " .exit = cleanup_module,\n");
- buf_printf(b, "#endif\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, "};\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)
- fprintf(stderr, "*** Warning: \"%s\" [%s.ko] "
- "undefined!\n", s->name, mod->name);
+ if (have_vmlinux && !s->weak) {
+ warn("\"%s\" [%s.ko] undefined!\n",
+ s->name, mod->name);
+ err = warn_unresolved ? 0 : 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");
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;
buf_printf(b, "\";\n");
}
-void
-write_if_changed(struct buffer *b, const char *fname)
+static void add_srcversion(struct buffer *b, struct module *mod)
+{
+ if (mod->srcversion[0]) {
+ buf_printf(b, "\n");
+ buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
+ mod->srcversion);
+ }
+}
+
+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);
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)) {
- modversions = 1;
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) {
- symbol = symbol->next;
- }
- }
-
- 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);
+ 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);
}
-int
-main(int argc, char **argv)
+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;
int opt;
+ int err;
- while ((opt = getopt(argc, argv, "i:o:")) != -1) {
+ while ((opt = getopt(argc, argv, "i:I:mo:aw")) != -1) {
switch(opt) {
case 'i':
- dump_read = optarg;
+ kernel_read = optarg;
+ break;
+ case 'I':
+ module_read = optarg;
+ external_module = 1;
+ break;
+ case 'm':
+ modversions = 1;
break;
case 'o':
dump_write = optarg;
break;
+ case 'a':
+ all_versions = 1;
+ break;
+ case 'w':
+ warn_unresolved = 1;
+ break;
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 (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) {
if (mod->skip)
continue;
buf.pos = 0;
- add_header(&buf);
- add_versions(&buf, mod);
+ add_header(&buf, mod);
+ err |= add_versions(&buf, mod);
add_depends(&buf, mod, modules);
add_moddevtable(&buf, mod);
+ add_srcversion(&buf, mod);
sprintf(fname, "%s.mod.c", mod->name);
write_if_changed(&buf, fname);
if (dump_write)
write_dump(dump_write);
- return 0;
+ return err;
}
-