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-rw-r--r--scripts/mod/modpost.c2681
1 files changed, 2681 insertions, 0 deletions
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
new file mode 100644
index 000000000..78ac98cfa
--- /dev/null
+++ b/scripts/mod/modpost.c
@@ -0,0 +1,2681 @@
+/* Postprocess module symbol versions
+ *
+ * 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
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ * Usage: modpost vmlinux module1.o module2.o ...
+ */
+
+#define _GNU_SOURCE
+#include <elf.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <string.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <errno.h>
+#include "modpost.h"
+#include "../../include/linux/license.h"
+
+/* Are we using CONFIG_MODVERSIONS? */
+static int modversions = 0;
+/* Warn about undefined symbols? (do so if we have vmlinux) */
+static 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 */
+static int sec_mismatch_count = 0;
+static int sec_mismatch_fatal = 0;
+/* ignore missing files */
+static int ignore_missing_files;
+/* If set to 1, only warn (instead of error) about missing ns imports */
+static int allow_missing_ns_imports;
+
+enum export {
+ export_plain, export_unused, export_gpl,
+ export_unused_gpl, export_gpl_future, export_unknown
+};
+
+/* In kernel, this size is defined in linux/module.h;
+ * here we use Elf_Addr instead of long for covering cross-compile
+ */
+
+#define MODULE_NAME_LEN (64 - sizeof(Elf_Addr))
+
+void __attribute__((format(printf, 2, 3)))
+modpost_log(enum loglevel loglevel, const char *fmt, ...)
+{
+ va_list arglist;
+
+ switch (loglevel) {
+ case LOG_WARN:
+ fprintf(stderr, "WARNING: ");
+ break;
+ case LOG_ERROR:
+ fprintf(stderr, "ERROR: ");
+ break;
+ case LOG_FATAL:
+ fprintf(stderr, "FATAL: ");
+ break;
+ default: /* invalid loglevel, ignore */
+ break;
+ }
+
+ fprintf(stderr, "modpost: ");
+
+ va_start(arglist, fmt);
+ vfprintf(stderr, fmt, arglist);
+ va_end(arglist);
+
+ if (loglevel == LOG_FATAL)
+ exit(1);
+}
+
+static inline bool strends(const char *str, const char *postfix)
+{
+ if (strlen(str) < strlen(postfix))
+ return false;
+
+ return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0;
+}
+
+void *do_nofail(void *ptr, const char *expr)
+{
+ if (!ptr)
+ fatal("Memory allocation failure: %s.\n", expr);
+
+ return ptr;
+}
+
+char *read_text_file(const char *filename)
+{
+ struct stat st;
+ size_t nbytes;
+ int fd;
+ char *buf;
+
+ fd = open(filename, O_RDONLY);
+ if (fd < 0) {
+ perror(filename);
+ exit(1);
+ }
+
+ if (fstat(fd, &st) < 0) {
+ perror(filename);
+ exit(1);
+ }
+
+ buf = NOFAIL(malloc(st.st_size + 1));
+
+ nbytes = st.st_size;
+
+ while (nbytes) {
+ ssize_t bytes_read;
+
+ bytes_read = read(fd, buf, nbytes);
+ if (bytes_read < 0) {
+ perror(filename);
+ exit(1);
+ }
+
+ nbytes -= bytes_read;
+ }
+ buf[st.st_size] = '\0';
+
+ close(fd);
+
+ return buf;
+}
+
+char *get_line(char **stringp)
+{
+ char *orig = *stringp, *next;
+
+ /* do not return the unwanted extra line at EOF */
+ if (!orig || *orig == '\0')
+ return NULL;
+
+ /* don't use strsep here, it is not available everywhere */
+ next = strchr(orig, '\n');
+ if (next)
+ *next++ = '\0';
+
+ *stringp = next;
+
+ return orig;
+}
+
+/* A list of all modules we processed */
+static struct module *modules;
+
+static struct module *find_module(const char *modname)
+{
+ struct module *mod;
+
+ for (mod = modules; mod; mod = mod->next)
+ if (strcmp(mod->name, modname) == 0)
+ break;
+ return mod;
+}
+
+static struct module *new_module(const char *modname)
+{
+ struct module *mod;
+
+ mod = NOFAIL(malloc(sizeof(*mod) + strlen(modname) + 1));
+ memset(mod, 0, sizeof(*mod));
+
+ /* add to list */
+ strcpy(mod->name, modname);
+ mod->is_vmlinux = (strcmp(modname, "vmlinux") == 0);
+ mod->gpl_compatible = -1;
+ mod->next = modules;
+ modules = mod;
+
+ if (mod->is_vmlinux)
+ have_vmlinux = 1;
+
+ return mod;
+}
+
+/* A hash of all exported symbols,
+ * struct symbol is also used for lists of unresolved symbols */
+
+#define SYMBOL_HASH_SIZE 1024
+
+struct symbol {
+ struct symbol *next;
+ struct module *module;
+ unsigned int crc;
+ int crc_valid;
+ char *namespace;
+ unsigned int weak:1;
+ unsigned int is_static:1; /* 1 if symbol is not global */
+ enum export export; /* Type of export */
+ char name[];
+};
+
+static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
+
+/* This is based on the hash agorithm from gdbm, via tdb */
+static inline unsigned int tdb_hash(const char *name)
+{
+ unsigned value; /* Used to compute the hash value. */
+ 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++)
+ 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
+ **/
+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;
+ s->is_static = 1;
+ return s;
+}
+
+/* For the hash of exported symbols */
+static struct symbol *new_symbol(const char *name, struct module *module,
+ enum export export)
+{
+ unsigned int hash;
+
+ hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
+ symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
+
+ return symbolhash[hash];
+}
+
+static struct symbol *find_symbol(const char *name)
+{
+ struct symbol *s;
+
+ /* For our purposes, .foo matches foo. PPC64 needs this. */
+ if (name[0] == '.')
+ name++;
+
+ for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
+ if (strcmp(s->name, name) == 0)
+ return s;
+ }
+ return NULL;
+}
+
+static bool contains_namespace(struct namespace_list *list,
+ const char *namespace)
+{
+ for (; list; list = list->next)
+ if (!strcmp(list->namespace, namespace))
+ return true;
+
+ return false;
+}
+
+static void add_namespace(struct namespace_list **list, const char *namespace)
+{
+ struct namespace_list *ns_entry;
+
+ if (!contains_namespace(*list, namespace)) {
+ ns_entry = NOFAIL(malloc(sizeof(struct namespace_list) +
+ strlen(namespace) + 1));
+ strcpy(ns_entry->namespace, namespace);
+ ns_entry->next = *list;
+ *list = ns_entry;
+ }
+}
+
+static bool module_imports_namespace(struct module *module,
+ const char *namespace)
+{
+ return contains_namespace(module->imported_namespaces, namespace);
+}
+
+static const 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 void *sym_get_data_by_offset(const struct elf_info *info,
+ unsigned int secindex, unsigned long offset)
+{
+ Elf_Shdr *sechdr = &info->sechdrs[secindex];
+
+ if (info->hdr->e_type != ET_REL)
+ offset -= sechdr->sh_addr;
+
+ return (void *)info->hdr + sechdr->sh_offset + offset;
+}
+
+static void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym)
+{
+ return sym_get_data_by_offset(info, get_secindex(info, sym),
+ sym->st_value);
+}
+
+static const char *sech_name(const struct elf_info *info, Elf_Shdr *sechdr)
+{
+ return sym_get_data_by_offset(info, info->secindex_strings,
+ sechdr->sh_name);
+}
+
+static const char *sec_name(const struct elf_info *info, int secindex)
+{
+ return sech_name(info, &info->sechdrs[secindex]);
+}
+
+#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
+
+static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
+{
+ const char *secname = sec_name(elf, sec);
+
+ if (strstarts(secname, "___ksymtab+"))
+ return export_plain;
+ else if (strstarts(secname, "___ksymtab_unused+"))
+ return export_unused;
+ else if (strstarts(secname, "___ksymtab_gpl+"))
+ return export_gpl;
+ else if (strstarts(secname, "___ksymtab_unused_gpl+"))
+ return export_unused_gpl;
+ else if (strstarts(secname, "___ksymtab_gpl_future+"))
+ return export_gpl_future;
+ else
+ return export_unknown;
+}
+
+static enum export export_from_sec(struct elf_info *elf, unsigned int 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;
+}
+
+static const char *namespace_from_kstrtabns(const struct elf_info *info,
+ const Elf_Sym *sym)
+{
+ const char *value = sym_get_data(info, sym);
+ return value[0] ? value : NULL;
+}
+
+static void sym_update_namespace(const char *symname, const char *namespace)
+{
+ struct symbol *s = find_symbol(symname);
+
+ /*
+ * That symbol should have been created earlier and thus this is
+ * actually an assertion.
+ */
+ if (!s) {
+ merror("Could not update namespace(%s) for symbol %s\n",
+ namespace, symname);
+ return;
+ }
+
+ free(s->namespace);
+ s->namespace =
+ namespace && namespace[0] ? NOFAIL(strdup(namespace)) : NULL;
+}
+
+/**
+ * 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) {
+ s = new_symbol(name, mod, export);
+ } else if (!external_module || s->module->is_vmlinux ||
+ s->module == mod) {
+ warn("%s: '%s' exported twice. Previous export was in %s%s\n",
+ mod->name, name, s->module->name,
+ s->module->is_vmlinux ? "" : ".ko");
+ return s;
+ }
+
+ s->module = mod;
+ s->export = export;
+ return s;
+}
+
+static void sym_set_crc(const char *name, unsigned int crc)
+{
+ struct symbol *s = find_symbol(name);
+
+ /*
+ * Ignore stand-alone __crc_*, which might be auto-generated symbols
+ * such as __*_veneer in ARM ELF.
+ */
+ if (!s)
+ return;
+
+ s->crc = crc;
+ s->crc_valid = 1;
+}
+
+static void *grab_file(const char *filename, size_t *size)
+{
+ struct stat st;
+ void *map = MAP_FAILED;
+ int fd;
+
+ fd = open(filename, O_RDONLY);
+ if (fd < 0)
+ return NULL;
+ if (fstat(fd, &st))
+ goto failed;
+
+ *size = st.st_size;
+ map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
+
+failed:
+ close(fd);
+ if (map == MAP_FAILED)
+ return NULL;
+ return map;
+}
+
+static void release_file(void *file, size_t size)
+{
+ munmap(file, size);
+}
+
+static int parse_elf(struct elf_info *info, const char *filename)
+{
+ unsigned int i;
+ Elf_Ehdr *hdr;
+ Elf_Shdr *sechdrs;
+ Elf_Sym *sym;
+ const char *secstrings;
+ unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
+
+ hdr = grab_file(filename, &info->size);
+ if (!hdr) {
+ if (ignore_missing_files) {
+ fprintf(stderr, "%s: %s (ignored)\n", filename,
+ strerror(errno));
+ return 0;
+ }
+ perror(filename);
+ exit(1);
+ }
+ info->hdr = hdr;
+ 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_type = TO_NATIVE(hdr->e_type);
+ hdr->e_machine = TO_NATIVE(hdr->e_machine);
+ hdr->e_version = TO_NATIVE(hdr->e_version);
+ hdr->e_entry = TO_NATIVE(hdr->e_entry);
+ hdr->e_phoff = TO_NATIVE(hdr->e_phoff);
+ hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
+ hdr->e_flags = TO_NATIVE(hdr->e_flags);
+ hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize);
+ hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
+ hdr->e_phnum = TO_NATIVE(hdr->e_phnum);
+ hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
+ hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
+ hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
+ 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=%zu\n",
+ (unsigned long)hdr->e_shoff, filename, info->size);
+ return 0;
+ }
+
+ if (hdr->e_shnum == SHN_UNDEF) {
+ /*
+ * There are more than 64k sections,
+ * read count from .sh_size.
+ */
+ info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
+ }
+ else {
+ info->num_sections = hdr->e_shnum;
+ }
+ if (hdr->e_shstrndx == SHN_XINDEX) {
+ info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
+ }
+ else {
+ info->secindex_strings = hdr->e_shstrndx;
+ }
+
+ /* Fix endianness in section headers */
+ for (i = 0; i < info->num_sections; i++) {
+ sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
+ sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
+ sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
+ sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
+ sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
+ sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
+ sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
+ sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
+ sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
+ sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
+ }
+ /* Find symbol table. */
+ secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
+ for (i = 1; i < info->num_sections; i++) {
+ const char *secname;
+ int nobits = sechdrs[i].sh_type == SHT_NOBITS;
+
+ if (!nobits && 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) {
+ if (nobits)
+ fatal("%s has NOBITS .modinfo\n", filename);
+ 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) {
+ unsigned int sh_link_idx;
+ symtab_idx = i;
+ info->symtab_start = (void *)hdr +
+ sechdrs[i].sh_offset;
+ info->symtab_stop = (void *)hdr +
+ sechdrs[i].sh_offset + sechdrs[i].sh_size;
+ sh_link_idx = sechdrs[i].sh_link;
+ info->strtab = (void *)hdr +
+ sechdrs[sh_link_idx].sh_offset;
+ }
+
+ /* 32bit section no. table? ("more than 64k sections") */
+ if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
+ symtab_shndx_idx = i;
+ info->symtab_shndx_start = (void *)hdr +
+ sechdrs[i].sh_offset;
+ info->symtab_shndx_stop = (void *)hdr +
+ sechdrs[i].sh_offset + sechdrs[i].sh_size;
+ }
+ }
+ 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_name = TO_NATIVE(sym->st_name);
+ sym->st_value = TO_NATIVE(sym->st_value);
+ sym->st_size = TO_NATIVE(sym->st_size);
+ }
+
+ if (symtab_shndx_idx != ~0U) {
+ Elf32_Word *p;
+ if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
+ fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
+ filename, sechdrs[symtab_shndx_idx].sh_link,
+ symtab_idx);
+ /* Fix endianness */
+ for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
+ p++)
+ *p = TO_NATIVE(*p);
+ }
+
+ return 1;
+}
+
+static void parse_elf_finish(struct elf_info *info)
+{
+ release_file(info->hdr, info->size);
+}
+
+static int ignore_undef_symbol(struct elf_info *info, const char *symname)
+{
+ /* ignore __this_module, it will be resolved shortly */
+ if (strcmp(symname, "__this_module") == 0)
+ return 1;
+ /* ignore global offset table */
+ if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
+ return 1;
+ if (info->hdr->e_machine == EM_PPC)
+ /* Special register function linked on all modules during final link of .ko */
+ if (strstarts(symname, "_restgpr_") ||
+ strstarts(symname, "_savegpr_") ||
+ strstarts(symname, "_rest32gpr_") ||
+ strstarts(symname, "_save32gpr_") ||
+ strstarts(symname, "_restvr_") ||
+ strstarts(symname, "_savevr_"))
+ return 1;
+ if (info->hdr->e_machine == EM_PPC64)
+ /* Special register function linked on all modules during final link of .ko */
+ if (strstarts(symname, "_restgpr0_") ||
+ strstarts(symname, "_savegpr0_") ||
+ strstarts(symname, "_restvr_") ||
+ strstarts(symname, "_savevr_") ||
+ strcmp(symname, ".TOC.") == 0)
+ return 1;
+ /* Do not ignore this symbol */
+ return 0;
+}
+
+static void handle_modversion(const struct module *mod,
+ const struct elf_info *info,
+ const Elf_Sym *sym, const char *symname)
+{
+ unsigned int crc;
+
+ if (sym->st_shndx == SHN_UNDEF) {
+ warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n",
+ symname, mod->name, mod->is_vmlinux ? "" : ".ko");
+ return;
+ }
+
+ if (sym->st_shndx == SHN_ABS) {
+ crc = sym->st_value;
+ } else {
+ unsigned int *crcp;
+
+ /* symbol points to the CRC in the ELF object */
+ crcp = sym_get_data(info, sym);
+ crc = TO_NATIVE(*crcp);
+ }
+ sym_set_crc(symname, crc);
+}
+
+static void handle_symbol(struct module *mod, struct elf_info *info,
+ const Elf_Sym *sym, const char *symname)
+{
+ enum export export;
+ const char *name;
+
+ if (strstarts(symname, "__ksymtab"))
+ export = export_from_secname(info, get_secindex(info, sym));
+ else
+ export = export_from_sec(info, get_secindex(info, sym));
+
+ switch (sym->st_shndx) {
+ case SHN_COMMON:
+ if (strstarts(symname, "__gnu_lto_")) {
+ /* Should warn here, but modpost runs before the linker */
+ } else
+ warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
+ break;
+ case SHN_UNDEF:
+ /* undefined symbol */
+ if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
+ ELF_ST_BIND(sym->st_info) != STB_WEAK)
+ break;
+ if (ignore_undef_symbol(info, symname))
+ break;
+ if (info->hdr->e_machine == EM_SPARC ||
+ info->hdr->e_machine == EM_SPARCV9) {
+ /* Ignore register directives. */
+ if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
+ break;
+ if (symname[0] == '.') {
+ char *munged = NOFAIL(strdup(symname));
+ munged[0] = '_';
+ munged[1] = toupper(munged[1]);
+ symname = munged;
+ }
+ }
+
+ mod->unres = alloc_symbol(symname,
+ ELF_ST_BIND(sym->st_info) == STB_WEAK,
+ mod->unres);
+ break;
+ default:
+ /* All exported symbols */
+ if (strstarts(symname, "__ksymtab_")) {
+ name = symname + strlen("__ksymtab_");
+ sym_add_exported(name, mod, export);
+ }
+ if (strcmp(symname, "init_module") == 0)
+ mod->has_init = 1;
+ if (strcmp(symname, "cleanup_module") == 0)
+ mod->has_cleanup = 1;
+ break;
+ }
+}
+
+/**
+ * Parse tag=value strings from .modinfo section
+ **/
+static char *next_string(char *string, unsigned long *secsize)
+{
+ /* Skip non-zero chars */
+ while (string[0]) {
+ string++;
+ if ((*secsize)-- <= 1)
+ return NULL;
+ }
+
+ /* Skip any zero padding. */
+ while (!string[0]) {
+ string++;
+ if ((*secsize)-- <= 1)
+ return NULL;
+ }
+ return string;
+}
+
+static char *get_next_modinfo(struct elf_info *info, const char *tag,
+ char *prev)
+{
+ char *p;
+ unsigned int taglen = strlen(tag);
+ char *modinfo = info->modinfo;
+ unsigned long size = info->modinfo_len;
+
+ if (prev) {
+ size -= prev - modinfo;
+ modinfo = next_string(prev, &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(struct elf_info *info, const char *tag)
+
+{
+ return get_next_modinfo(info, 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)";
+}
+
+/* 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 that contains "foo"
+ */
+static 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 == '*' && *endp == '*') {
+ char *bare = NOFAIL(strndup(p + 1, strlen(p) - 2));
+ char *here = strstr(sym, bare);
+
+ free(bare);
+ if (here != NULL)
+ return 1;
+ }
+ /* "*foo" */
+ else if (*p == '*') {
+ if (strrcmp(sym, p + 1) == 0)
+ return 1;
+ }
+ /* "foo*" */
+ else if (*endp == '*') {
+ if (strncmp(sym, p, strlen(p) - 1) == 0)
+ 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 *const section_white_list[] =
+{
+ ".comment*",
+ ".debug*",
+ ".cranges", /* sh64 */
+ ".zdebug*", /* Compressed debug sections. */
+ ".GCC.command.line", /* record-gcc-switches */
+ ".mdebug*", /* alpha, score, mips etc. */
+ ".pdr", /* alpha, score, mips etc. */
+ ".stab*",
+ ".note*",
+ ".got*",
+ ".toc*",
+ ".xt.prop", /* xtensa */
+ ".xt.lit", /* xtensa */
+ ".arcextmap*", /* arc */
+ ".gnu.linkonce.arcext*", /* arc : modules */
+ ".cmem*", /* EZchip */
+ ".fmt_slot*", /* EZchip */
+ ".gnu.lto*",
+ ".discard.*",
+ NULL
+};
+
+/*
+ * This is used to find sections missing the SHF_ALLOC flag.
+ * The cause of this is often a section specified in assembler
+ * without "ax" / "aw".
+ */
+static void check_section(const char *modname, struct elf_info *elf,
+ Elf_Shdr *sechdr)
+{
+ const char *sec = sech_name(elf, sechdr);
+
+ if (sechdr->sh_type == SHT_PROGBITS &&
+ !(sechdr->sh_flags & SHF_ALLOC) &&
+ !match(sec, section_white_list)) {
+ warn("%s (%s): unexpected non-allocatable section.\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);
+ }
+}
+
+
+
+#define ALL_INIT_DATA_SECTIONS \
+ ".init.setup", ".init.rodata", ".meminit.rodata", \
+ ".init.data", ".meminit.data"
+#define ALL_EXIT_DATA_SECTIONS \
+ ".exit.data", ".memexit.data"
+
+#define ALL_INIT_TEXT_SECTIONS \
+ ".init.text", ".meminit.text"
+#define ALL_EXIT_TEXT_SECTIONS \
+ ".exit.text", ".memexit.text"
+
+#define ALL_PCI_INIT_SECTIONS \
+ ".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \
+ ".pci_fixup_enable", ".pci_fixup_resume", \
+ ".pci_fixup_resume_early", ".pci_fixup_suspend"
+
+#define ALL_XXXINIT_SECTIONS MEM_INIT_SECTIONS
+#define ALL_XXXEXIT_SECTIONS MEM_EXIT_SECTIONS
+
+#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
+#define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
+
+#define DATA_SECTIONS ".data", ".data.rel"
+#define TEXT_SECTIONS ".text", ".text.unlikely", ".sched.text", \
+ ".kprobes.text", ".cpuidle.text", ".noinstr.text"
+#define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \
+ ".fixup", ".entry.text", ".exception.text", ".text.*", \
+ ".coldtext"
+
+#define INIT_SECTIONS ".init.*"
+#define MEM_INIT_SECTIONS ".meminit.*"
+
+#define EXIT_SECTIONS ".exit.*"
+#define MEM_EXIT_SECTIONS ".memexit.*"
+
+#define ALL_TEXT_SECTIONS ALL_INIT_TEXT_SECTIONS, ALL_EXIT_TEXT_SECTIONS, \
+ TEXT_SECTIONS, OTHER_TEXT_SECTIONS
+
+/* init data sections */
+static const char *const init_data_sections[] =
+ { ALL_INIT_DATA_SECTIONS, NULL };
+
+/* all init sections */
+static const char *const init_sections[] = { ALL_INIT_SECTIONS, NULL };
+
+/* All init and exit sections (code + data) */
+static const char *const init_exit_sections[] =
+ {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
+
+/* all text sections */
+static const char *const text_sections[] = { ALL_TEXT_SECTIONS, NULL };
+
+/* data section */
+static const char *const data_sections[] = { DATA_SECTIONS, NULL };
+
+
+/* symbols in .data that may refer to init/exit sections */
+#define DEFAULT_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"
+
+static const char *const head_sections[] = { ".head.text*", NULL };
+static const char *const linker_symbols[] =
+ { "__init_begin", "_sinittext", "_einittext", NULL };
+static const char *const optim_symbols[] = { "*.constprop.*", NULL };
+
+enum mismatch {
+ TEXT_TO_ANY_INIT,
+ DATA_TO_ANY_INIT,
+ TEXT_TO_ANY_EXIT,
+ DATA_TO_ANY_EXIT,
+ XXXINIT_TO_SOME_INIT,
+ XXXEXIT_TO_SOME_EXIT,
+ ANY_INIT_TO_ANY_EXIT,
+ ANY_EXIT_TO_ANY_INIT,
+ EXPORT_TO_INIT_EXIT,
+ EXTABLE_TO_NON_TEXT,
+};
+
+/**
+ * Describe how to match sections on different criterias:
+ *
+ * @fromsec: Array of sections to be matched.
+ *
+ * @bad_tosec: Relocations applied to a section in @fromsec to a section in
+ * this array is forbidden (black-list). Can be empty.
+ *
+ * @good_tosec: Relocations applied to a section in @fromsec must be
+ * targetting sections in this array (white-list). Can be empty.
+ *
+ * @mismatch: Type of mismatch.
+ *
+ * @symbol_white_list: Do not match a relocation to a symbol in this list
+ * even if it is targetting a section in @bad_to_sec.
+ *
+ * @handler: Specific handler to call when a match is found. If NULL,
+ * default_mismatch_handler() will be called.
+ *
+ */
+struct sectioncheck {
+ const char *fromsec[20];
+ const char *bad_tosec[20];
+ const char *good_tosec[20];
+ enum mismatch mismatch;
+ const char *symbol_white_list[20];
+ void (*handler)(const char *modname, struct elf_info *elf,
+ const struct sectioncheck* const mismatch,
+ Elf_Rela *r, Elf_Sym *sym, const char *fromsec);
+
+};
+
+static void extable_mismatch_handler(const char *modname, struct elf_info *elf,
+ const struct sectioncheck* const mismatch,
+ Elf_Rela *r, Elf_Sym *sym,
+ const char *fromsec);
+
+static const struct sectioncheck sectioncheck[] = {
+/* Do not reference init/exit code/data from
+ * normal code and data
+ */
+{
+ .fromsec = { TEXT_SECTIONS, NULL },
+ .bad_tosec = { ALL_INIT_SECTIONS, NULL },
+ .mismatch = TEXT_TO_ANY_INIT,
+ .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
+},
+{
+ .fromsec = { DATA_SECTIONS, NULL },
+ .bad_tosec = { ALL_XXXINIT_SECTIONS, NULL },
+ .mismatch = DATA_TO_ANY_INIT,
+ .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
+},
+{
+ .fromsec = { DATA_SECTIONS, NULL },
+ .bad_tosec = { INIT_SECTIONS, NULL },
+ .mismatch = DATA_TO_ANY_INIT,
+ .symbol_white_list = {
+ "*_template", "*_timer", "*_sht", "*_ops",
+ "*_probe", "*_probe_one", "*_console", NULL
+ },
+},
+{
+ .fromsec = { TEXT_SECTIONS, NULL },
+ .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
+ .mismatch = TEXT_TO_ANY_EXIT,
+ .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
+},
+{
+ .fromsec = { DATA_SECTIONS, NULL },
+ .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
+ .mismatch = DATA_TO_ANY_EXIT,
+ .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
+},
+/* Do not reference init code/data from meminit code/data */
+{
+ .fromsec = { ALL_XXXINIT_SECTIONS, NULL },
+ .bad_tosec = { INIT_SECTIONS, NULL },
+ .mismatch = XXXINIT_TO_SOME_INIT,
+ .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
+},
+/* Do not reference exit code/data from memexit code/data */
+{
+ .fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
+ .bad_tosec = { EXIT_SECTIONS, NULL },
+ .mismatch = XXXEXIT_TO_SOME_EXIT,
+ .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
+},
+/* Do not use exit code/data from init code */
+{
+ .fromsec = { ALL_INIT_SECTIONS, NULL },
+ .bad_tosec = { ALL_EXIT_SECTIONS, NULL },
+ .mismatch = ANY_INIT_TO_ANY_EXIT,
+ .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
+},
+/* Do not use init code/data from exit code */
+{
+ .fromsec = { ALL_EXIT_SECTIONS, NULL },
+ .bad_tosec = { ALL_INIT_SECTIONS, NULL },
+ .mismatch = ANY_EXIT_TO_ANY_INIT,
+ .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
+},
+{
+ .fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
+ .bad_tosec = { INIT_SECTIONS, NULL },
+ .mismatch = ANY_INIT_TO_ANY_EXIT,
+ .symbol_white_list = { NULL },
+},
+/* Do not export init/exit functions or data */
+{
+ .fromsec = { "___ksymtab*", NULL },
+ .bad_tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
+ .mismatch = EXPORT_TO_INIT_EXIT,
+ .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
+},
+{
+ .fromsec = { "__ex_table", NULL },
+ /* If you're adding any new black-listed sections in here, consider
+ * adding a special 'printer' for them in scripts/check_extable.
+ */
+ .bad_tosec = { ".altinstr_replacement", NULL },
+ .good_tosec = {ALL_TEXT_SECTIONS , NULL},
+ .mismatch = EXTABLE_TO_NON_TEXT,
+ .handler = extable_mismatch_handler,
+}
+};
+
+static const struct sectioncheck *section_mismatch(
+ const char *fromsec, const char *tosec)
+{
+ int i;
+ int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck);
+ const struct sectioncheck *check = &sectioncheck[0];
+
+ /*
+ * The target section could be the SHT_NUL section when we're
+ * handling relocations to un-resolved symbols, trying to match it
+ * doesn't make much sense and causes build failures on parisc
+ * architectures.
+ */
+ if (*tosec == '\0')
+ return NULL;
+
+ for (i = 0; i < elems; i++) {
+ if (match(fromsec, check->fromsec)) {
+ if (check->bad_tosec[0] && match(tosec, check->bad_tosec))
+ return check;
+ if (check->good_tosec[0] && !match(tosec, check->good_tosec))
+ return check;
+ }
+ check++;
+ }
+ return NULL;
+}
+
+/**
+ * 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 1a:
+ * module_param_call() ops can refer to __init set function if permissions=0
+ * The pattern is identified by:
+ * tosec = .init.text
+ * fromsec = .data*
+ * atsym = __param_ops_*
+ *
+ * Pattern 2:
+ * Many drivers utilise a *driver container with references to
+ * add, remove, probe functions etc.
+ * 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 references from .head.text to any init section
+ *
+ * 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:
+ * GCC may optimize static inlines when fed constant arg(s) resulting
+ * in functions like cpumask_empty() -- generating an associated symbol
+ * cpumask_empty.constprop.3 that appears in the audit. If the const that
+ * is passed in comes from __init, like say nmi_ipi_mask, we get a
+ * meaningless section warning. May need to add isra symbols too...
+ * This pattern is identified by
+ * tosec = init section
+ * fromsec = text section
+ * refsymname = *.constprop.*
+ *
+ * Pattern 6:
+ * Hide section mismatch warnings for ELF local symbols. The goal
+ * is to eliminate false positive modpost warnings caused by
+ * compiler-generated ELF local symbol names such as ".LANCHOR1".
+ * Autogenerated symbol names bypass modpost's "Pattern 2"
+ * whitelisting, which relies on pattern-matching against symbol
+ * names to work. (One situation where gcc can autogenerate ELF
+ * local symbols is when "-fsection-anchors" is used.)
+ **/
+static int secref_whitelist(const struct sectioncheck *mismatch,
+ const char *fromsec, const char *fromsym,
+ const char *tosec, const char *tosym)
+{
+ /* Check for pattern 1 */
+ if (match(tosec, init_data_sections) &&
+ match(fromsec, data_sections) &&
+ strstarts(fromsym, "__param"))
+ return 0;
+
+ /* Check for pattern 1a */
+ if (strcmp(tosec, ".init.text") == 0 &&
+ match(fromsec, data_sections) &&
+ strstarts(fromsym, "__param_ops_"))
+ return 0;
+
+ /* Check for pattern 2 */
+ if (match(tosec, init_exit_sections) &&
+ match(fromsec, data_sections) &&
+ match(fromsym, mismatch->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;
+
+ /* Check for pattern 5 */
+ if (match(fromsec, text_sections) &&
+ match(tosec, init_sections) &&
+ match(fromsym, optim_symbols))
+ return 0;
+
+ /* Check for pattern 6 */
+ if (strstarts(fromsym, ".L"))
+ return 0;
+
+ return 1;
+}
+
+static inline int is_arm_mapping_symbol(const char *str)
+{
+ return str[0] == '$' &&
+ (str[1] == 'a' || str[1] == 'd' || str[1] == 't' || str[1] == 'x')
+ && (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 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;
+ unsigned int relsym_secindex;
+
+ if (relsym->st_name != 0)
+ return relsym;
+
+ /*
+ * Strive to find a better symbol name, but the resulting name may not
+ * match the symbol referenced in the original code.
+ */
+ relsym_secindex = get_secindex(elf, relsym);
+ for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
+ if (get_secindex(elf, sym) != relsym_secindex)
+ continue;
+ if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
+ continue;
+ if (!is_valid_name(elf, sym))
+ 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;
+}
+
+/*
+ * 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 (is_shndx_special(sym->st_shndx))
+ continue;
+ symsec = sec_name(elf, get_secindex(elf, sym));
+ 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
+ * .memexitconst => __memconst
+ * etc.
+ *
+ * The memory of returned value has been allocated on a heap. The user of this
+ * method should free it after usage.
+*/
+static char *sec2annotation(const char *s)
+{
+ if (match(s, init_exit_sections)) {
+ char *p = NOFAIL(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;
+ } else {
+ return NOFAIL(strdup(""));
+ }
+}
+
+static int is_function(Elf_Sym *sym)
+{
+ if (sym)
+ return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
+ else
+ return -1;
+}
+
+static void print_section_list(const char * const list[20])
+{
+ const char *const *s = list;
+
+ while (*s) {
+ fprintf(stderr, "%s", *s);
+ s++;
+ if (*s)
+ fprintf(stderr, ", ");
+ }
+ fprintf(stderr, "\n");
+}
+
+static inline void get_pretty_name(int is_func, const char** name, const char** name_p)
+{
+ switch (is_func) {
+ case 0: *name = "variable"; *name_p = ""; break;
+ case 1: *name = "function"; *name_p = "()"; break;
+ default: *name = "(unknown reference)"; *name_p = ""; break;
+ }
+}
+
+/*
+ * 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,
+ const struct sectioncheck *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;
+ char *prl_from;
+ char *prl_to;
+
+ sec_mismatch_count++;
+
+ get_pretty_name(from_is_func, &from, &from_p);
+ get_pretty_name(to_is_func, &to, &to_p);
+
+ 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->mismatch) {
+ case TEXT_TO_ANY_INIT:
+ prl_from = sec2annotation(fromsec);
+ prl_to = sec2annotation(tosec);
+ 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",
+ prl_from, fromsym,
+ to, prl_to, tosym, to_p,
+ fromsym, prl_to, tosym);
+ free(prl_from);
+ free(prl_to);
+ break;
+ case DATA_TO_ANY_INIT: {
+ prl_to = sec2annotation(tosec);
+ 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* or __refdata (see linux/init.h) "
+ "or name the variable:\n",
+ fromsym, to, prl_to, tosym, to_p);
+ print_section_list(mismatch->symbol_white_list);
+ free(prl_to);
+ break;
+ }
+ case TEXT_TO_ANY_EXIT:
+ prl_to = sec2annotation(tosec);
+ 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, prl_to, tosym);
+ free(prl_to);
+ break;
+ case DATA_TO_ANY_EXIT: {
+ prl_to = sec2annotation(tosec);
+ 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, prl_to, tosym, to_p);
+ print_section_list(mismatch->symbol_white_list);
+ free(prl_to);
+ break;
+ }
+ case XXXINIT_TO_SOME_INIT:
+ case XXXEXIT_TO_SOME_EXIT:
+ prl_from = sec2annotation(fromsec);
+ prl_to = sec2annotation(tosec);
+ 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, prl_from, fromsym, from_p,
+ to, prl_to, tosym, to_p,
+ tosym, fromsym, tosym);
+ free(prl_from);
+ free(prl_to);
+ break;
+ case ANY_INIT_TO_ANY_EXIT:
+ prl_from = sec2annotation(fromsec);
+ prl_to = sec2annotation(tosec);
+ 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, prl_from, fromsym, from_p,
+ to, prl_to, tosym, to_p,
+ prl_to, tosym, to_p);
+ free(prl_from);
+ free(prl_to);
+ break;
+ case ANY_EXIT_TO_ANY_INIT:
+ prl_from = sec2annotation(fromsec);
+ prl_to = sec2annotation(tosec);
+ 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, prl_from, fromsym, from_p,
+ to, prl_to, tosym, to_p,
+ prl_to, tosym, to_p);
+ free(prl_from);
+ free(prl_to);
+ break;
+ case EXPORT_TO_INIT_EXIT:
+ prl_to = sec2annotation(tosec);
+ 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, prl_to, prl_to, tosym);
+ free(prl_to);
+ break;
+ case EXTABLE_TO_NON_TEXT:
+ fatal("There's a special handler for this mismatch type, "
+ "we should never get here.");
+ break;
+ }
+ fprintf(stderr, "\n");
+}
+
+static void default_mismatch_handler(const char *modname, struct elf_info *elf,
+ const struct sectioncheck* const mismatch,
+ Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
+{
+ const char *tosec;
+ 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);
+
+ if (strstarts(fromsym, "reference___initcall"))
+ return;
+
+ tosec = sec_name(elf, get_secindex(elf, sym));
+ to = find_elf_symbol(elf, r->r_addend, sym);
+ tosym = sym_name(elf, to);
+
+ /* check whitelist - we may ignore it */
+ if (secref_whitelist(mismatch,
+ fromsec, fromsym, tosec, tosym)) {
+ report_sec_mismatch(modname, mismatch,
+ fromsec, r->r_offset, fromsym,
+ is_function(from), tosec, tosym,
+ is_function(to));
+ }
+}
+
+static int is_executable_section(struct elf_info* elf, unsigned int section_index)
+{
+ if (section_index >= elf->num_sections)
+ fatal("section_index is outside elf->num_sections!\n");
+
+ return ((elf->sechdrs[section_index].sh_flags & SHF_EXECINSTR) == SHF_EXECINSTR);
+}
+
+/*
+ * We rely on a gross hack in section_rel[a]() calling find_extable_entry_size()
+ * to know the sizeof(struct exception_table_entry) for the target architecture.
+ */
+static unsigned int extable_entry_size = 0;
+static void find_extable_entry_size(const char* const sec, const Elf_Rela* r)
+{
+ /*
+ * If we're currently checking the second relocation within __ex_table,
+ * that relocation offset tells us the offsetof(struct
+ * exception_table_entry, fixup) which is equal to sizeof(struct
+ * exception_table_entry) divided by two. We use that to our advantage
+ * since there's no portable way to get that size as every architecture
+ * seems to go with different sized types. Not pretty but better than
+ * hard-coding the size for every architecture..
+ */
+ if (!extable_entry_size)
+ extable_entry_size = r->r_offset * 2;
+}
+
+static inline bool is_extable_fault_address(Elf_Rela *r)
+{
+ /*
+ * extable_entry_size is only discovered after we've handled the
+ * _second_ relocation in __ex_table, so only abort when we're not
+ * handling the first reloc and extable_entry_size is zero.
+ */
+ if (r->r_offset && extable_entry_size == 0)
+ fatal("extable_entry size hasn't been discovered!\n");
+
+ return ((r->r_offset == 0) ||
+ (r->r_offset % extable_entry_size == 0));
+}
+
+#define is_second_extable_reloc(Start, Cur, Sec) \
+ (((Cur) == (Start) + 1) && (strcmp("__ex_table", (Sec)) == 0))
+
+static void report_extable_warnings(const char* modname, struct elf_info* elf,
+ const struct sectioncheck* const mismatch,
+ Elf_Rela* r, Elf_Sym* sym,
+ const char* fromsec, const char* tosec)
+{
+ Elf_Sym* fromsym = find_elf_symbol2(elf, r->r_offset, fromsec);
+ const char* fromsym_name = sym_name(elf, fromsym);
+ Elf_Sym* tosym = find_elf_symbol(elf, r->r_addend, sym);
+ const char* tosym_name = sym_name(elf, tosym);
+ const char* from_pretty_name;
+ const char* from_pretty_name_p;
+ const char* to_pretty_name;
+ const char* to_pretty_name_p;
+
+ get_pretty_name(is_function(fromsym),
+ &from_pretty_name, &from_pretty_name_p);
+ get_pretty_name(is_function(tosym),
+ &to_pretty_name, &to_pretty_name_p);
+
+ warn("%s(%s+0x%lx): Section mismatch in reference"
+ " from the %s %s%s to the %s %s:%s%s\n",
+ modname, fromsec, (long)r->r_offset, from_pretty_name,
+ fromsym_name, from_pretty_name_p,
+ to_pretty_name, tosec, tosym_name, to_pretty_name_p);
+
+ if (!match(tosec, mismatch->bad_tosec) &&
+ is_executable_section(elf, get_secindex(elf, sym)))
+ fprintf(stderr,
+ "The relocation at %s+0x%lx references\n"
+ "section \"%s\" which is not in the list of\n"
+ "authorized sections. If you're adding a new section\n"
+ "and/or if this reference is valid, add \"%s\" to the\n"
+ "list of authorized sections to jump to on fault.\n"
+ "This can be achieved by adding \"%s\" to \n"
+ "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n",
+ fromsec, (long)r->r_offset, tosec, tosec, tosec);
+}
+
+static void extable_mismatch_handler(const char* modname, struct elf_info *elf,
+ const struct sectioncheck* const mismatch,
+ Elf_Rela* r, Elf_Sym* sym,
+ const char *fromsec)
+{
+ const char* tosec = sec_name(elf, get_secindex(elf, sym));
+
+ sec_mismatch_count++;
+
+ report_extable_warnings(modname, elf, mismatch, r, sym, fromsec, tosec);
+
+ if (match(tosec, mismatch->bad_tosec))
+ fatal("The relocation at %s+0x%lx references\n"
+ "section \"%s\" which is black-listed.\n"
+ "Something is seriously wrong and should be fixed.\n"
+ "You might get more information about where this is\n"
+ "coming from by using scripts/check_extable.sh %s\n",
+ fromsec, (long)r->r_offset, tosec, modname);
+ else if (!is_executable_section(elf, get_secindex(elf, sym))) {
+ if (is_extable_fault_address(r))
+ fatal("The relocation at %s+0x%lx references\n"
+ "section \"%s\" which is not executable, IOW\n"
+ "it is not possible for the kernel to fault\n"
+ "at that address. Something is seriously wrong\n"
+ "and should be fixed.\n",
+ fromsec, (long)r->r_offset, tosec);
+ else
+ fatal("The relocation at %s+0x%lx references\n"
+ "section \"%s\" which is not executable, IOW\n"
+ "the kernel will fault if it ever tries to\n"
+ "jump to it. Something is seriously wrong\n"
+ "and should be fixed.\n",
+ fromsec, (long)r->r_offset, tosec);
+ }
+}
+
+static void check_section_mismatch(const char *modname, struct elf_info *elf,
+ Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
+{
+ const char *tosec = sec_name(elf, get_secindex(elf, sym));
+ const struct sectioncheck *mismatch = section_mismatch(fromsec, tosec);
+
+ if (mismatch) {
+ if (mismatch->handler)
+ mismatch->handler(modname, elf, mismatch,
+ r, sym, fromsec);
+ else
+ default_mismatch_handler(modname, elf, mismatch,
+ r, sym, fromsec);
+ }
+}
+
+static unsigned int *reloc_location(struct elf_info *elf,
+ Elf_Shdr *sechdr, Elf_Rela *r)
+{
+ return sym_get_data_by_offset(elf, sechdr->sh_info, r->r_offset);
+}
+
+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;
+}
+
+#ifndef R_ARM_CALL
+#define R_ARM_CALL 28
+#endif
+#ifndef R_ARM_JUMP24
+#define R_ARM_JUMP24 29
+#endif
+
+#ifndef R_ARM_THM_CALL
+#define R_ARM_THM_CALL 10
+#endif
+#ifndef R_ARM_THM_JUMP24
+#define R_ARM_THM_JUMP24 30
+#endif
+#ifndef R_ARM_THM_JUMP19
+#define R_ARM_THM_JUMP19 51
+#endif
+
+static int32_t sign_extend32(int32_t value, int index)
+{
+ uint8_t shift = 31 - index;
+
+ return (int32_t)(value << shift) >> shift;
+}
+
+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);
+ Elf_Sym *sym = elf->symtab_start + ELF_R_SYM(r->r_info);
+ void *loc = reloc_location(elf, sechdr, r);
+ uint32_t inst;
+ int32_t offset;
+
+ switch (r_typ) {
+ case R_ARM_ABS32:
+ inst = TO_NATIVE(*(uint32_t *)loc);
+ r->r_addend = inst + sym->st_value;
+ break;
+ case R_ARM_PC24:
+ case R_ARM_CALL:
+ case R_ARM_JUMP24:
+ inst = TO_NATIVE(*(uint32_t *)loc);
+ offset = sign_extend32((inst & 0x00ffffff) << 2, 25);
+ r->r_addend = offset + sym->st_value + 8;
+ break;
+ case R_ARM_THM_CALL:
+ case R_ARM_THM_JUMP24:
+ case R_ARM_THM_JUMP19:
+ /* 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 (match(fromsec, section_white_list))
+ 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 (is_shndx_special(sym->st_shndx))
+ continue;
+ if (is_second_extable_reloc(start, rela, fromsec))
+ find_extable_entry_size(fromsec, &r);
+ 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 (match(fromsec, section_white_list))
+ 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 (is_shndx_special(sym->st_shndx))
+ continue;
+ if (is_second_extable_reloc(start, rel, fromsec))
+ find_extable_entry_size(fromsec, &r);
+ 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 initialized.
+ * Likewise for modules used built-in the sections marked __exit
+ * are discarded because __exit marked function are supposed to be called
+ * only when a module is unloaded which never happens 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->num_sections; i++) {
+ check_section(modname, elf, &elf->sechdrs[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 char *remove_dot(char *s)
+{
+ size_t n = strcspn(s, ".");
+
+ if (n && s[n]) {
+ size_t m = strspn(s + n + 1, "0123456789");
+ if (m && (s[n + m + 1] == '.' || s[n + m + 1] == 0))
+ s[n] = 0;
+ }
+ return s;
+}
+
+static void read_symbols(const char *modname)
+{
+ const char *symname;
+ char *version;
+ char *license;
+ char *namespace;
+ struct module *mod;
+ struct elf_info info = { };
+ Elf_Sym *sym;
+
+ if (!parse_elf(&info, modname))
+ return;
+
+ {
+ char *tmp;
+
+ /* strip trailing .o */
+ tmp = NOFAIL(strdup(modname));
+ tmp[strlen(tmp) - 2] = '\0';
+ mod = new_module(tmp);
+ free(tmp);
+ }
+
+ if (!mod->is_vmlinux) {
+ license = get_modinfo(&info, "license");
+ if (!license)
+ warn("missing MODULE_LICENSE() in %s\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, "license", license);
+ }
+
+ namespace = get_modinfo(&info, "import_ns");
+ while (namespace) {
+ add_namespace(&mod->imported_namespaces, namespace);
+ namespace = get_next_modinfo(&info, "import_ns",
+ namespace);
+ }
+ }
+
+ for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
+ symname = remove_dot(info.strtab + sym->st_name);
+
+ handle_symbol(mod, &info, sym, symname);
+ handle_moddevtable(mod, &info, sym, symname);
+ }
+
+ for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
+ symname = remove_dot(info.strtab + sym->st_name);
+
+ /* Apply symbol namespaces from __kstrtabns_<symbol> entries. */
+ if (strstarts(symname, "__kstrtabns_"))
+ sym_update_namespace(symname + strlen("__kstrtabns_"),
+ namespace_from_kstrtabns(&info,
+ sym));
+
+ if (strstarts(symname, "__crc_"))
+ handle_modversion(mod, &info, sym,
+ symname + strlen("__crc_"));
+ }
+
+ // check for static EXPORT_SYMBOL_* functions && global vars
+ for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
+ unsigned char bind = ELF_ST_BIND(sym->st_info);
+
+ if (bind == STB_GLOBAL || bind == STB_WEAK) {
+ struct symbol *s =
+ find_symbol(remove_dot(info.strtab +
+ sym->st_name));
+
+ if (s)
+ s->is_static = 0;
+ }
+ }
+
+ check_sec_ref(mod, modname, &info);
+
+ if (!mod->is_vmlinux) {
+ version = get_modinfo(&info, "version");
+ if (version || all_versions)
+ get_src_version(modname, mod->srcversion,
+ sizeof(mod->srcversion) - 1);
+ }
+
+ parse_elf_finish(&info);
+
+ /* Our trick to get versioning for module struct etc. - 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("module_layout", 0, mod->unres);
+}
+
+static void read_symbols_from_files(const char *filename)
+{
+ FILE *in = stdin;
+ char fname[PATH_MAX];
+
+ if (strcmp(filename, "-") != 0) {
+ in = fopen(filename, "r");
+ if (!in)
+ fatal("Can't open filenames file %s: %m", filename);
+ }
+
+ while (fgets(fname, PATH_MAX, in) != NULL) {
+ if (strends(fname, "\n"))
+ fname[strlen(fname)-1] = '\0';
+ read_symbols(fname);
+ }
+
+ if (in != stdin)
+ fclose(in);
+}
+
+#define SZ 500
+
+/* We first write the generated file into memory using the
+ * 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, ...)
+{
+ char tmp[SZ];
+ int len;
+ va_list ap;
+
+ va_start(ap, fmt);
+ len = vsnprintf(tmp, SZ, fmt, ap);
+ 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 + SZ;
+ buf->p = NOFAIL(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)
+{
+ switch (exp) {
+ case export_gpl:
+ fatal("GPL-incompatible module %s.ko uses GPL-only symbol '%s'\n",
+ m, s);
+ break;
+ case export_unused_gpl:
+ fatal("GPL-incompatible module %s.ko uses GPL-only symbol marked UNUSED '%s'\n",
+ m, s);
+ break;
+ case export_gpl_future:
+ warn("GPL-incompatible module %s.ko uses future GPL-only symbol '%s'\n",
+ m, 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)
+{
+ switch (exp) {
+ case export_unused:
+ case export_unused_gpl:
+ warn("module %s.ko uses symbol '%s' marked UNUSED\n",
+ m, s);
+ break;
+ default:
+ /* ignore */
+ break;
+ }
+}
+
+static int check_exports(struct module *mod)
+{
+ struct symbol *s, *exp;
+ int err = 0;
+
+ for (s = mod->unres; s; s = s->next) {
+ const char *basename;
+ exp = find_symbol(s->name);
+ if (!exp || exp->module == mod) {
+ if (have_vmlinux && !s->weak) {
+ modpost_log(warn_unresolved ? LOG_WARN : LOG_ERROR,
+ "\"%s\" [%s.ko] undefined!\n",
+ s->name, mod->name);
+ if (!warn_unresolved)
+ err = 1;
+ }
+ continue;
+ }
+ basename = strrchr(mod->name, '/');
+ if (basename)
+ basename++;
+ else
+ basename = mod->name;
+
+ if (exp->namespace &&
+ !module_imports_namespace(mod, exp->namespace)) {
+ modpost_log(allow_missing_ns_imports ? LOG_WARN : LOG_ERROR,
+ "module %s uses symbol %s from namespace %s, but does not import it.\n",
+ basename, exp->name, exp->namespace);
+ if (!allow_missing_ns_imports)
+ err = 1;
+ add_namespace(&mod->missing_namespaces, exp->namespace);
+ }
+
+ if (!mod->gpl_compatible)
+ check_for_gpl_usage(exp->export, basename, exp->name);
+ check_for_unused(exp->export, basename, exp->name);
+ }
+
+ return err;
+}
+
+static int check_modname_len(struct module *mod)
+{
+ const char *mod_name;
+
+ mod_name = strrchr(mod->name, '/');
+ if (mod_name == NULL)
+ mod_name = mod->name;
+ else
+ mod_name++;
+ if (strlen(mod_name) >= MODULE_NAME_LEN) {
+ merror("module name is too long [%s.ko]\n", mod->name);
+ return 1;
+ }
+
+ return 0;
+}
+
+/**
+ * Header for the generated file
+ **/
+static void add_header(struct buffer *b, struct module *mod)
+{
+ buf_printf(b, "#include <linux/module.h>\n");
+ /*
+ * Include build-salt.h after module.h in order to
+ * inherit the definitions.
+ */
+ buf_printf(b, "#define INCLUDE_VERMAGIC\n");
+ buf_printf(b, "#include <linux/build-salt.h>\n");
+ buf_printf(b, "#include <linux/vermagic.h>\n");
+ buf_printf(b, "#include <linux/compiler.h>\n");
+ buf_printf(b, "\n");
+ buf_printf(b, "BUILD_SALT;\n");
+ buf_printf(b, "\n");
+ buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
+ buf_printf(b, "MODULE_INFO(name, KBUILD_MODNAME);\n");
+ buf_printf(b, "\n");
+ buf_printf(b, "__visible struct module __this_module\n");
+ buf_printf(b, "__section(\".gnu.linkonce.this_module\") = {\n");
+ buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
+ if (mod->has_init)
+ buf_printf(b, "\t.init = init_module,\n");
+ if (mod->has_cleanup)
+ buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
+ "\t.exit = cleanup_module,\n"
+ "#endif\n");
+ buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
+ buf_printf(b, "};\n");
+}
+
+static void add_intree_flag(struct buffer *b, int is_intree)
+{
+ if (is_intree)
+ buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
+}
+
+/* Cannot check for assembler */
+static void add_retpoline(struct buffer *b)
+{
+ buf_printf(b, "\n#ifdef CONFIG_RETPOLINE\n");
+ buf_printf(b, "MODULE_INFO(retpoline, \"Y\");\n");
+ buf_printf(b, "#endif\n");
+}
+
+static void add_staging_flag(struct buffer *b, const char *name)
+{
+ if (strstarts(name, "drivers/staging"))
+ buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
+}
+
+/**
+ * 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)
+ continue;
+ s->module = exp->module;
+ s->crc_valid = exp->crc_valid;
+ s->crc = exp->crc;
+ }
+
+ if (!modversions)
+ return err;
+
+ buf_printf(b, "\n");
+ buf_printf(b, "static const struct modversion_info ____versions[]\n");
+ buf_printf(b, "__used __section(\"__versions\") = {\n");
+
+ for (s = mod->unres; s; s = s->next) {
+ if (!s->module)
+ continue;
+ if (!s->crc_valid) {
+ warn("\"%s\" [%s.ko] has no CRC!\n",
+ s->name, mod->name);
+ continue;
+ }
+ if (strlen(s->name) >= MODULE_NAME_LEN) {
+ merror("too long symbol \"%s\" [%s.ko]\n",
+ s->name, mod->name);
+ err = 1;
+ break;
+ }
+ buf_printf(b, "\t{ %#8x, \"%s\" },\n",
+ s->crc, s->name);
+ }
+
+ buf_printf(b, "};\n");
+
+ return err;
+}
+
+static void add_depends(struct buffer *b, struct module *mod)
+{
+ struct symbol *s;
+ int first = 1;
+
+ /* Clear ->seen flag of modules that own symbols needed by this. */
+ for (s = mod->unres; s; s = s->next)
+ if (s->module)
+ s->module->seen = s->module->is_vmlinux;
+
+ buf_printf(b, "\n");
+ buf_printf(b, "MODULE_INFO(depends, \"");
+ for (s = mod->unres; s; s = s->next) {
+ const char *p;
+ if (!s->module)
+ continue;
+
+ if (s->module->seen)
+ continue;
+
+ s->module->seen = 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");
+}
+
+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_buf(struct buffer *b, const char *fname)
+{
+ FILE *file;
+
+ file = fopen(fname, "w");
+ if (!file) {
+ perror(fname);
+ exit(1);
+ }
+ if (fwrite(b->p, 1, b->pos, file) != b->pos) {
+ perror(fname);
+ exit(1);
+ }
+ if (fclose(file) != 0) {
+ perror(fname);
+ exit(1);
+ }
+}
+
+static void write_if_changed(struct buffer *b, const char *fname)
+{
+ char *tmp;
+ FILE *file;
+ struct stat st;
+
+ file = fopen(fname, "r");
+ if (!file)
+ goto write;
+
+ if (fstat(fileno(file), &st) < 0)
+ goto close_write;
+
+ if (st.st_size != b->pos)
+ goto close_write;
+
+ tmp = NOFAIL(malloc(b->pos));
+ if (fread(tmp, 1, b->pos, file) != b->pos)
+ goto free_write;
+
+ if (memcmp(tmp, b->p, b->pos) != 0)
+ goto free_write;
+
+ free(tmp);
+ fclose(file);
+ return;
+
+ free_write:
+ free(tmp);
+ close_write:
+ fclose(file);
+ write:
+ write_buf(b, fname);
+}
+
+/* parse Module.symvers file. line format:
+ * 0x12345678<tab>symbol<tab>module<tab>export<tab>namespace
+ **/
+static void read_dump(const char *fname)
+{
+ char *buf, *pos, *line;
+
+ buf = read_text_file(fname);
+ if (!buf)
+ /* No symbol versions, silently ignore */
+ return;
+
+ pos = buf;
+
+ while ((line = get_line(&pos))) {
+ char *symname, *namespace, *modname, *d, *export;
+ unsigned int crc;
+ struct module *mod;
+ struct symbol *s;
+
+ if (!(symname = strchr(line, '\t')))
+ goto fail;
+ *symname++ = '\0';
+ if (!(modname = strchr(symname, '\t')))
+ goto fail;
+ *modname++ = '\0';
+ if (!(export = strchr(modname, '\t')))
+ goto fail;
+ *export++ = '\0';
+ if (!(namespace = strchr(export, '\t')))
+ goto fail;
+ *namespace++ = '\0';
+
+ crc = strtoul(line, &d, 16);
+ if (*symname == '\0' || *modname == '\0' || *d != '\0')
+ goto fail;
+ mod = find_module(modname);
+ if (!mod) {
+ mod = new_module(modname);
+ mod->from_dump = 1;
+ }
+ s = sym_add_exported(symname, mod, export_no(export));
+ s->is_static = 0;
+ sym_set_crc(symname, crc);
+ sym_update_namespace(symname, namespace);
+ }
+ free(buf);
+ return;
+fail:
+ free(buf);
+ fatal("parse error in symbol dump file\n");
+}
+
+static void write_dump(const char *fname)
+{
+ struct buffer buf = { };
+ struct symbol *symbol;
+ const char *namespace;
+ int n;
+
+ for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
+ symbol = symbolhash[n];
+ while (symbol) {
+ if (!symbol->module->from_dump) {
+ namespace = symbol->namespace;
+ buf_printf(&buf, "0x%08x\t%s\t%s\t%s\t%s\n",
+ symbol->crc, symbol->name,
+ symbol->module->name,
+ export_str(symbol->export),
+ namespace ? namespace : "");
+ }
+ symbol = symbol->next;
+ }
+ }
+ write_buf(&buf, fname);
+ free(buf.p);
+}
+
+static void write_namespace_deps_files(const char *fname)
+{
+ struct module *mod;
+ struct namespace_list *ns;
+ struct buffer ns_deps_buf = {};
+
+ for (mod = modules; mod; mod = mod->next) {
+
+ if (mod->from_dump || !mod->missing_namespaces)
+ continue;
+
+ buf_printf(&ns_deps_buf, "%s.ko:", mod->name);
+
+ for (ns = mod->missing_namespaces; ns; ns = ns->next)
+ buf_printf(&ns_deps_buf, " %s", ns->namespace);
+
+ buf_printf(&ns_deps_buf, "\n");
+ }
+
+ write_if_changed(&ns_deps_buf, fname);
+ free(ns_deps_buf.p);
+}
+
+struct dump_list {
+ struct dump_list *next;
+ const char *file;
+};
+
+int main(int argc, char **argv)
+{
+ struct module *mod;
+ struct buffer buf = { };
+ char *missing_namespace_deps = NULL;
+ char *dump_write = NULL, *files_source = NULL;
+ int opt;
+ int err;
+ int n;
+ struct dump_list *dump_read_start = NULL;
+ struct dump_list **dump_read_iter = &dump_read_start;
+
+ while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:")) != -1) {
+ switch (opt) {
+ case 'e':
+ external_module = 1;
+ break;
+ case 'i':
+ *dump_read_iter =
+ NOFAIL(calloc(1, sizeof(**dump_read_iter)));
+ (*dump_read_iter)->file = optarg;
+ dump_read_iter = &(*dump_read_iter)->next;
+ break;
+ case 'm':
+ modversions = 1;
+ break;
+ case 'n':
+ ignore_missing_files = 1;
+ break;
+ case 'o':
+ dump_write = optarg;
+ break;
+ case 'a':
+ all_versions = 1;
+ break;
+ case 'T':
+ files_source = optarg;
+ break;
+ case 'w':
+ warn_unresolved = 1;
+ break;
+ case 'E':
+ sec_mismatch_fatal = 1;
+ break;
+ case 'N':
+ allow_missing_ns_imports = 1;
+ break;
+ case 'd':
+ missing_namespace_deps = optarg;
+ break;
+ default:
+ exit(1);
+ }
+ }
+
+ while (dump_read_start) {
+ struct dump_list *tmp;
+
+ read_dump(dump_read_start->file);
+ tmp = dump_read_start->next;
+ free(dump_read_start);
+ dump_read_start = tmp;
+ }
+
+ while (optind < argc)
+ read_symbols(argv[optind++]);
+
+ if (files_source)
+ read_symbols_from_files(files_source);
+
+ /*
+ * When there's no vmlinux, don't print warnings about
+ * unresolved symbols (since there'll be too many ;)
+ */
+ if (!have_vmlinux)
+ warn("Symbol info of vmlinux is missing. Unresolved symbol check will be entirely skipped.\n");
+
+ err = 0;
+
+ for (mod = modules; mod; mod = mod->next) {
+ char fname[PATH_MAX];
+
+ if (mod->is_vmlinux || mod->from_dump)
+ continue;
+
+ buf.pos = 0;
+
+ err |= check_modname_len(mod);
+ err |= check_exports(mod);
+
+ add_header(&buf, mod);
+ add_intree_flag(&buf, !external_module);
+ add_retpoline(&buf);
+ add_staging_flag(&buf, mod->name);
+ err |= add_versions(&buf, mod);
+ add_depends(&buf, mod);
+ add_moddevtable(&buf, mod);
+ add_srcversion(&buf, mod);
+
+ sprintf(fname, "%s.mod.c", mod->name);
+ write_if_changed(&buf, fname);
+ }
+
+ if (missing_namespace_deps)
+ write_namespace_deps_files(missing_namespace_deps);
+
+ if (dump_write)
+ write_dump(dump_write);
+ if (sec_mismatch_count && sec_mismatch_fatal)
+ fatal("Section mismatches detected.\n"
+ "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n");
+ for (n = 0; n < SYMBOL_HASH_SIZE; n++) {
+ struct symbol *s;
+
+ for (s = symbolhash[n]; s; s = s->next) {
+ if (s->is_static)
+ warn("\"%s\" [%s] is a static %s\n",
+ s->name, s->module->name,
+ export_str(s->export));
+ }
+ }
+
+ free(buf.p);
+
+ return err;
+}