X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=scripts%2Fmod%2Fmodpost.c;h=20923613467cf376db195e17a9df754e934ab470;hb=ce384d83d00ee457c3931d3fdb9fa2c38e345a3c;hp=3bed09e625c0b52c8d52f762af6ee6dfd7c86cba;hpb=7caaeabb17758295edff9703c18a840073c5b8f4;p=safe%2Fjmp%2Flinux-2.6 diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 3bed09e..2092361 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -2,7 +2,7 @@ * * 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 @@ -11,8 +11,20 @@ * Usage: modpost vmlinux module1.o module2.o ... */ +#define _GNU_SOURCE +#include #include #include "modpost.h" +#include "../../include/generated/autoconf.h" +#include "../../include/linux/license.h" + +/* Some toolchains use a `_' prefix for all user symbols. */ +#ifdef CONFIG_SYMBOL_PREFIX +#define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX +#else +#define MODULE_SYMBOL_PREFIX "" +#endif + /* Are we using CONFIG_MODVERSIONS? */ int modversions = 0; @@ -20,9 +32,24 @@ int modversions = 0; int have_vmlinux = 0; /* Is CONFIG_MODULE_SRCVERSION_ALL set? */ static int all_versions = 0; +/* If we are modposting external module set to 1 */ +static int external_module = 0; +/* Warn about section mismatch in vmlinux if set to 1 */ +static int vmlinux_section_warnings = 1; +/* Only warn about unresolved symbols */ +static int warn_unresolved = 0; +/* How a symbol is exported */ +static int sec_mismatch_count = 0; +static int sec_mismatch_verbose = 1; + +enum export { + export_plain, export_unused, export_gpl, + export_unused_gpl, export_gpl_future, export_unknown +}; -void -fatal(const char *fmt, ...) +#define PRINTF __attribute__ ((format (printf, 1, 2))) + +PRINTF void fatal(const char *fmt, ...) { va_list arglist; @@ -35,8 +62,7 @@ fatal(const char *fmt, ...) exit(1); } -void -warn(const char *fmt, ...) +PRINTF void warn(const char *fmt, ...) { va_list arglist; @@ -47,20 +73,43 @@ warn(const char *fmt, ...) va_end(arglist); } +PRINTF void merror(const char *fmt, ...) +{ + va_list arglist; + + fprintf(stderr, "ERROR: "); + + va_start(arglist, fmt); + vfprintf(stderr, fmt, arglist); + va_end(arglist); +} + +static int is_vmlinux(const char *modname) +{ + const char *myname; + + myname = strrchr(modname, '/'); + if (myname) + myname++; + else + myname = modname; + + return (strcmp(myname, "vmlinux") == 0) || + (strcmp(myname, "vmlinux.o") == 0); +} + void *do_nofail(void *ptr, const char *expr) { - if (!ptr) { + if (!ptr) fatal("modpost: Memory allocation failure: %s.\n", expr); - } + return ptr; } /* A list of all modules we processed */ - static struct module *modules; -struct module * -find_module(char *modname) +static struct module *find_module(char *modname) { struct module *mod; @@ -70,23 +119,24 @@ find_module(char *modname) return mod; } -struct module * -new_module(char *modname) +static struct module *new_module(char *modname) { struct module *mod; char *p, *s; - + mod = NOFAIL(malloc(sizeof(*mod))); memset(mod, 0, sizeof(*mod)); p = NOFAIL(strdup(modname)); /* strip trailing .o */ - if ((s = strrchr(p, '.')) != NULL) + s = strrchr(p, '.'); + if (s != NULL) if (strcmp(s, ".o") == 0) *s = '\0'; /* add to list */ mod->name = p; + mod->gpl_compatible = -1; mod->next = modules; modules = mod; @@ -104,6 +154,11 @@ struct symbol { 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]; }; @@ -116,17 +171,18 @@ static inline unsigned int tdb_hash(const char *name) unsigned i; /* Used to cycle through random values. */ /* Set the initial value from the key size. */ - for (value = 0x238F13AF * strlen(name), i=0; name[i]; i++) + for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++) value = (value + (((unsigned char *)name)[i] << (i*5 % 24))); return (1103515243 * value + 12345); } -/* Allocate a new symbols for use in the hash of exported symbols or - * the list of unresolved symbols per module */ - -struct symbol * -alloc_symbol(const char *name, unsigned int weak, struct symbol *next) +/** + * Allocate a new symbols for use in the hash of exported symbols or + * the list of unresolved symbols per module + **/ +static struct symbol *alloc_symbol(const char *name, unsigned int weak, + struct symbol *next) { struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1)); @@ -138,9 +194,8 @@ alloc_symbol(const char *name, unsigned int weak, struct symbol *next) } /* 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; @@ -148,14 +203,11 @@ new_symbol(const char *name, struct module *module, unsigned int *crc) hash = tdb_hash(name) % SYMBOL_HASH_SIZE; new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]); new->module = module; - if (crc) { - new->crc = *crc; - new->crc_valid = 1; - } + new->export = export; + return new; } -struct symbol * -find_symbol(const char *name) +static struct symbol *find_symbol(const char *name) { struct symbol *s; @@ -163,32 +215,101 @@ find_symbol(const char *name) if (name[0] == '.') name++; - for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s=s->next) { + for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) { if (strcmp(s->name, name) == 0) return s; } return NULL; } -/* Add an exported symbol - it may have already been added without a - * CRC, in this case just update the CRC */ -void -add_exported_symbol(const char *name, struct module *module, unsigned int *crc) +static struct { + const char *str; + enum export export; +} export_list[] = { + { .str = "EXPORT_SYMBOL", .export = export_plain }, + { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused }, + { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl }, + { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl }, + { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future }, + { .str = "(unknown)", .export = export_unknown }, +}; + + +static const char *export_str(enum export ex) +{ + return export_list[ex].str; +} + +static enum export export_no(const char *s) +{ + int i; + + if (!s) + return export_unknown; + for (i = 0; export_list[i].export != export_unknown; i++) { + if (strcmp(export_list[i].str, s) == 0) + return export_list[i].export; + } + return export_unknown; +} + +static enum export export_from_sec(struct elf_info *elf, Elf_Section sec) +{ + if (sec == elf->export_sec) + return export_plain; + else if (sec == elf->export_unused_sec) + return export_unused; + else if (sec == elf->export_gpl_sec) + return export_gpl; + else if (sec == elf->export_unused_gpl_sec) + return export_unused_gpl; + else if (sec == elf->export_gpl_future_sec) + return export_gpl_future; + else + return export_unknown; +} + +/** + * Add an exported symbol - it may have already been added without a + * CRC, in this case just update the CRC + **/ +static struct symbol *sym_add_exported(const char *name, struct module *mod, + enum export export) { struct symbol *s = find_symbol(name); if (!s) { - new_symbol(name, module, crc); - return; - } - if (crc) { - s->crc = *crc; - s->crc_valid = 1; + s = new_symbol(name, mod, export); + } else { + if (!s->preloaded) { + warn("%s: '%s' exported twice. Previous export " + "was in %s%s\n", mod->name, name, + s->module->name, + is_vmlinux(s->module->name) ?"":".ko"); + } else { + /* In case Modules.symvers was out of date */ + s->module = mod; + } } + s->preloaded = 0; + s->vmlinux = is_vmlinux(mod->name); + s->kernel = 0; + s->export = export; + return s; } -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; @@ -207,13 +328,12 @@ grab_file(const char *filename, unsigned long *size) 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; @@ -221,8 +341,7 @@ get_next_line(unsigned long *pos, void *file, unsigned long size) signed char *p = (signed char *)file + *pos; char *s = line; - for (; *pos < size ; (*pos)++) - { + for (; *pos < size ; (*pos)++) { if (skip && isspace(*p)) { p++; continue; @@ -243,69 +362,117 @@ get_next_line(unsigned long *pos, void *file, unsigned long size) return NULL; } -void -release_file(void *file, unsigned long size) +void release_file(void *file, unsigned long size) { munmap(file, size); } -void -parse_elf(struct elf_info *info, const char *filename) +static int parse_elf(struct elf_info *info, const char *filename) { unsigned int i; - Elf_Ehdr *hdr = info->hdr; + Elf_Ehdr *hdr; Elf_Shdr *sechdrs; Elf_Sym *sym; hdr = grab_file(filename, &info->size); if (!hdr) { perror(filename); - abort(); + exit(1); } info->hdr = hdr; - if (info->size < sizeof(*hdr)) - goto truncated; - + if (info->size < sizeof(*hdr)) { + /* file too small, assume this is an empty .o file */ + return 0; + } + /* Is this a valid ELF file? */ + if ((hdr->e_ident[EI_MAG0] != ELFMAG0) || + (hdr->e_ident[EI_MAG1] != ELFMAG1) || + (hdr->e_ident[EI_MAG2] != ELFMAG2) || + (hdr->e_ident[EI_MAG3] != ELFMAG3)) { + /* Not an ELF file - silently ignore it */ + return 0; + } /* Fix endianness in ELF header */ - hdr->e_shoff = TO_NATIVE(hdr->e_shoff); - hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx); - hdr->e_shnum = TO_NATIVE(hdr->e_shnum); - hdr->e_machine = TO_NATIVE(hdr->e_machine); + hdr->e_type = TO_NATIVE(hdr->e_type); + 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=%lu\n", (unsigned long)hdr->e_shoff, + filename, info->size); + return 0; + } + /* Fix endianness in section headers */ for (i = 0; i < hdr->e_shnum; i++) { - sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type); - sechdrs[i].sh_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_name = TO_NATIVE(sechdrs[i].sh_name); + 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. */ for (i = 1; i < hdr->e_shnum; i++) { const char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; - - if (sechdrs[i].sh_offset > info->size) - goto truncated; - if (strcmp(secstrings+sechdrs[i].sh_name, ".modinfo") == 0) { + const char *secname; + 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) continue; info->symtab_start = (void *)hdr + sechdrs[i].sh_offset; - info->symtab_stop = (void *)hdr + sechdrs[i].sh_offset + info->symtab_stop = (void *)hdr + sechdrs[i].sh_offset + sechdrs[i].sh_size; - info->strtab = (void *)hdr + + info->strtab = (void *)hdr + sechdrs[sechdrs[i].sh_link].sh_offset; } - if (!info->symtab_start) { - fprintf(stderr, "modpost: %s no symtab?\n", filename); - abort(); - } + if (!info->symtab_start) + fatal("%s has no symtab?\n", filename); + /* Fix endianness in symbols */ for (sym = info->symtab_start; sym < info->symtab_stop; sym++) { sym->st_shndx = TO_NATIVE(sym->st_shndx); @@ -313,39 +480,52 @@ parse_elf(struct elf_info *info, const char *filename) sym->st_value = TO_NATIVE(sym->st_value); sym->st_size = TO_NATIVE(sym->st_size); } - return; - - truncated: - fprintf(stderr, "modpost: %s is truncated.\n", filename); - abort(); + return 1; } -void -parse_elf_finish(struct elf_info *info) +static void parse_elf_finish(struct elf_info *info) { release_file(info->hdr, info->size); } +static int ignore_undef_symbol(struct elf_info *info, const char *symname) +{ + /* ignore __this_module, it will be resolved shortly */ + if (strcmp(symname, MODULE_SYMBOL_PREFIX "__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 (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 || + strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 || + strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 || + strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0) + return 1; + /* Do not ignore this symbol */ + return 0; +} + #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) { + if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) { crc = (unsigned int) sym->st_value; - add_exported_symbol(symname + strlen(CRC_PFX), - mod, &crc); + sym_update_crc(symname + strlen(CRC_PFX), mod, crc, + export); } break; case SHN_UNDEF: @@ -353,11 +533,7 @@ handle_modversions(struct module *mod, struct elf_info *info, 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) - break; - /* ignore __this_module, it will be resolved shortly */ - if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0) + if (ignore_undef_symbol(info, symname)) break; /* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */ #if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER) @@ -370,27 +546,29 @@ handle_modversions(struct module *mod, struct elf_info *info, /* Ignore register directives. */ if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER) break; - if (symname[0] == '.') { - char *munged = strdup(symname); - munged[0] = '_'; - munged[1] = toupper(munged[1]); - symname = munged; - } + if (symname[0] == '.') { + char *munged = strdup(symname); + munged[0] = '_'; + munged[1] = toupper(munged[1]); + symname = munged; + } } #endif - + if (memcmp(symname, MODULE_SYMBOL_PREFIX, - strlen(MODULE_SYMBOL_PREFIX)) == 0) - mod->unres = alloc_symbol(symname + - strlen(MODULE_SYMBOL_PREFIX), - ELF_ST_BIND(sym->st_info) == STB_WEAK, - mod->unres); + strlen(MODULE_SYMBOL_PREFIX)) == 0) { + mod->unres = + alloc_symbol(symname + + strlen(MODULE_SYMBOL_PREFIX), + ELF_ST_BIND(sym->st_info) == STB_WEAK, + mod->unres); + } break; default: /* All exported symbols */ - if (memcmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) { - add_exported_symbol(symname + strlen(KSYMTAB_PFX), - mod, NULL); + if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) { + sym_add_exported(symname + strlen(KSYMTAB_PFX), mod, + export); } if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0) mod->has_init = 1; @@ -400,20 +578,9 @@ handle_modversions(struct module *mod, struct elf_info *info, } } -int -is_vmlinux(const char *modname) -{ - const char *myname; - - if ((myname = strrchr(modname, '/'))) - myname++; - else - myname = modname; - - return strcmp(myname, "vmlinux") == 0; -} - -/* Parse tag=value strings from .modinfo section */ +/** + * Parse tag=value strings from .modinfo section + **/ static char *next_string(char *string, unsigned long *secsize) { /* Skip non-zero chars */ @@ -432,13 +599,18 @@ static char *next_string(char *string, unsigned long *secsize) return string; } -static char *get_modinfo(void *modinfo, unsigned long modinfo_len, - const char *tag) +static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len, + const char *tag, char *info) { char *p; unsigned int taglen = strlen(tag); unsigned long size = modinfo_len; + if (info) { + size -= info - (char *)modinfo; + modinfo = next_string(info, &size); + } + for (p = modinfo; p; p = next_string(p, &size)) { if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') return p + taglen + 1; @@ -446,34 +618,950 @@ static char *get_modinfo(void *modinfo, unsigned long modinfo_len, return NULL; } -void -read_symbols(char *modname) +static char *get_modinfo(void *modinfo, unsigned long modinfo_len, + const char *tag) + +{ + return get_next_modinfo(modinfo, modinfo_len, tag, NULL); +} + +/** + * Test if string s ends in string sub + * return 0 if match + **/ +static int strrcmp(const char *s, const char *sub) +{ + int slen, sublen; + + if (!s || !sub) + return 1; + + slen = strlen(s); + sublen = strlen(sub); + + if ((slen == 0) || (sublen == 0)) + return 1; + + if (sublen > slen) + return 1; + + return memcmp(s + slen - sublen, sub, sublen); +} + +static const char *sym_name(struct elf_info *elf, Elf_Sym *sym) +{ + if (sym) + return elf->strtab + sym->st_name; + else + return "(unknown)"; +} + +static const char *sec_name(struct elf_info *elf, int shndx) +{ + Elf_Shdr *sechdrs = elf->sechdrs; + return (void *)elf->hdr + + elf->sechdrs[elf->hdr->e_shstrndx].sh_offset + + sechdrs[shndx].sh_name; +} + +static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr) +{ + return (void *)elf->hdr + + elf->sechdrs[elf->hdr->e_shstrndx].sh_offset + + sechdr->sh_name; +} + +/* if sym is empty or point to a string + * like ".[0-9]+" then return 1. + * This is the optional prefix added by ld to some sections + */ +static int number_prefix(const char *sym) +{ + if (*sym++ == '\0') + return 1; + if (*sym != '.') + return 0; + do { + char c = *sym++; + if (c < '0' || c > '9') + return 0; + } while (*sym); + return 1; +} + +/* The pattern is an array of simple patterns. + * "foo" will match an exact string equal to "foo" + * "*foo" will match a string that ends with "foo" + * "foo*" will match a string that begins with "foo" + * "foo$" will match a string equal to "foo" or "foo.1" + * where the '1' can be any number including several digits. + * The $ syntax is for sections where ld append a dot number + * to make section name unique. + */ +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 == '*') { + if (strrcmp(sym, p + 1) == 0) + return 1; + } + /* "foo*" */ + else if (*endp == '*') { + if (strncmp(sym, p, strlen(p) - 1) == 0) + return 1; + } + /* "foo$" */ + else if (*endp == '$') { + if (strncmp(sym, p, strlen(p) - 1) == 0) { + if (number_prefix(sym + strlen(p) - 1)) + return 1; + } + } + /* no wildcards */ + else { + if (strcmp(p, sym) == 0) + return 1; + } + } + /* no match */ + return 0; +} + +/* sections that we do not want to do full section mismatch check on */ +static const char *section_white_list[] = +{ + ".comment*", + ".debug*", + ".mdebug*", /* alpha, score, mips etc. */ + ".pdr", /* alpha, score, mips etc. */ + ".stab*", + ".note*", + ".got*", + ".toc*", + 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 contains\n" + "section definitions for use in .S files.\n\n", + modname, sec); + } +} + + + +#define ALL_INIT_DATA_SECTIONS \ + ".init.setup$", ".init.rodata$", \ + ".devinit.rodata$", ".cpuinit.rodata$", ".meminit.rodata$" \ + ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$" +#define ALL_EXIT_DATA_SECTIONS \ + ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$" + +#define ALL_INIT_TEXT_SECTIONS \ + ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$" +#define ALL_EXIT_TEXT_SECTIONS \ + ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$" + +#define ALL_INIT_SECTIONS INIT_SECTIONS, DEV_INIT_SECTIONS, \ + CPU_INIT_SECTIONS, MEM_INIT_SECTIONS +#define ALL_EXIT_SECTIONS EXIT_SECTIONS, DEV_EXIT_SECTIONS, \ + CPU_EXIT_SECTIONS, MEM_EXIT_SECTIONS + +#define DATA_SECTIONS ".data$", ".data.rel$" +#define TEXT_SECTIONS ".text$" + +#define INIT_SECTIONS ".init.*" +#define DEV_INIT_SECTIONS ".devinit.*" +#define CPU_INIT_SECTIONS ".cpuinit.*" +#define MEM_INIT_SECTIONS ".meminit.*" + +#define EXIT_SECTIONS ".exit.*" +#define DEV_EXIT_SECTIONS ".devexit.*" +#define CPU_EXIT_SECTIONS ".cpuexit.*" +#define MEM_EXIT_SECTIONS ".memexit.*" + +/* init data sections */ +static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL }; + +/* all init sections */ +static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL }; + +/* All init and exit sections (code + data) */ +static const char *init_exit_sections[] = + {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL }; + +/* data section */ +static const char *data_sections[] = { DATA_SECTIONS, NULL }; + + +/* symbols in .data that may refer to init/exit sections */ +static const char *symbol_white_list[] = +{ + "*driver", + "*_template", /* scsi uses *_template a lot */ + "*_timer", /* arm uses ops structures named _timer a lot */ + "*_sht", /* scsi also used *_sht to some extent */ + "*_ops", + "*_probe", + "*_probe_one", + "*_console", + NULL +}; + +static const char *head_sections[] = { ".head.text*", NULL }; +static const char *linker_symbols[] = + { "__init_begin", "_sinittext", "_einittext", NULL }; + +enum mismatch { + NO_MISMATCH, + TEXT_TO_INIT, + DATA_TO_INIT, + TEXT_TO_EXIT, + DATA_TO_EXIT, + XXXINIT_TO_INIT, + XXXEXIT_TO_EXIT, + INIT_TO_EXIT, + EXIT_TO_INIT, + EXPORT_TO_INIT_EXIT, +}; + +struct sectioncheck { + const char *fromsec[20]; + const char *tosec[20]; + enum mismatch mismatch; +}; + +const struct sectioncheck sectioncheck[] = { +/* Do not reference init/exit code/data from + * normal code and data + */ +{ + .fromsec = { TEXT_SECTIONS, NULL }, + .tosec = { ALL_INIT_SECTIONS, NULL }, + .mismatch = TEXT_TO_INIT, +}, +{ + .fromsec = { DATA_SECTIONS, NULL }, + .tosec = { ALL_INIT_SECTIONS, NULL }, + .mismatch = DATA_TO_INIT, +}, +{ + .fromsec = { TEXT_SECTIONS, NULL }, + .tosec = { ALL_EXIT_SECTIONS, NULL }, + .mismatch = TEXT_TO_EXIT, +}, +{ + .fromsec = { DATA_SECTIONS, NULL }, + .tosec = { ALL_EXIT_SECTIONS, NULL }, + .mismatch = DATA_TO_EXIT, +}, +/* Do not reference init code/data from devinit/cpuinit/meminit code/data */ +{ + .fromsec = { DEV_INIT_SECTIONS, CPU_INIT_SECTIONS, MEM_INIT_SECTIONS, NULL }, + .tosec = { INIT_SECTIONS, NULL }, + .mismatch = XXXINIT_TO_INIT, +}, +/* Do not reference cpuinit code/data from meminit code/data */ +{ + .fromsec = { MEM_INIT_SECTIONS, NULL }, + .tosec = { CPU_INIT_SECTIONS, NULL }, + .mismatch = XXXINIT_TO_INIT, +}, +/* Do not reference meminit code/data from cpuinit code/data */ +{ + .fromsec = { CPU_INIT_SECTIONS, NULL }, + .tosec = { MEM_INIT_SECTIONS, NULL }, + .mismatch = XXXINIT_TO_INIT, +}, +/* Do not reference exit code/data from devexit/cpuexit/memexit code/data */ +{ + .fromsec = { DEV_EXIT_SECTIONS, CPU_EXIT_SECTIONS, MEM_EXIT_SECTIONS, NULL }, + .tosec = { EXIT_SECTIONS, NULL }, + .mismatch = XXXEXIT_TO_EXIT, +}, +/* Do not reference cpuexit code/data from memexit code/data */ +{ + .fromsec = { MEM_EXIT_SECTIONS, NULL }, + .tosec = { CPU_EXIT_SECTIONS, NULL }, + .mismatch = XXXEXIT_TO_EXIT, +}, +/* Do not reference memexit code/data from cpuexit code/data */ +{ + .fromsec = { CPU_EXIT_SECTIONS, NULL }, + .tosec = { MEM_EXIT_SECTIONS, NULL }, + .mismatch = XXXEXIT_TO_EXIT, +}, +/* Do not use exit code/data from init code */ +{ + .fromsec = { ALL_INIT_SECTIONS, NULL }, + .tosec = { ALL_EXIT_SECTIONS, NULL }, + .mismatch = INIT_TO_EXIT, +}, +/* Do not use init code/data from exit code */ +{ + .fromsec = { ALL_EXIT_SECTIONS, NULL }, + .tosec = { ALL_INIT_SECTIONS, NULL }, + .mismatch = EXIT_TO_INIT, +}, +/* Do not export init/exit functions or data */ +{ + .fromsec = { "__ksymtab*", NULL }, + .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL }, + .mismatch = EXPORT_TO_INIT_EXIT +} +}; + +static int section_mismatch(const char *fromsec, const char *tosec) +{ + int i; + int elems = sizeof(sectioncheck) / sizeof(struct sectioncheck); + const struct sectioncheck *check = §ioncheck[0]; + + for (i = 0; i < elems; i++) { + if (match(fromsec, check->fromsec) && + match(tosec, check->tosec)) + return check->mismatch; + check++; + } + return NO_MISMATCH; +} + +/** + * Whitelist to allow certain references to pass with no warning. + * + * Pattern 1: + * If a module parameter is declared __initdata and permissions=0 + * then this is legal despite the warning generated. + * We cannot see value of permissions here, so just ignore + * this pattern. + * The pattern is identified by: + * tosec = .init.data + * fromsec = .data* + * atsym =__param* + * + * Pattern 2: + * Many drivers utilise a *driver container with references to + * add, remove, probe functions etc. + * These functions may often be marked __init and we do not want to + * warn here. + * the pattern is identified by: + * tosec = init or exit section + * fromsec = data section + * atsym = *driver, *_template, *_sht, *_ops, *_probe, + * *probe_one, *_console, *_timer + * + * Pattern 3: + * Whitelist all 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 + * + **/ +static int secref_whitelist(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) && + (strncmp(fromsym, "__param", strlen("__param")) == 0)) + return 0; + + /* Check for pattern 2 */ + if (match(tosec, init_exit_sections) && + match(fromsec, data_sections) && + match(fromsym, symbol_white_list)) + return 0; + + /* Check for pattern 3 */ + if (match(fromsec, head_sections) && + match(tosec, init_sections)) + return 0; + + /* Check for pattern 4 */ + if (match(tosym, linker_symbols)) + return 0; + + return 1; +} + +/** + * Find symbol based on relocation record info. + * In some cases the symbol supplied is a valid symbol so + * return refsym. If st_name != 0 we assume this is a valid symbol. + * In other cases the symbol needs to be looked up in the symbol table + * based on section and address. + * **/ +static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr, + Elf_Sym *relsym) +{ + Elf_Sym *sym; + Elf_Sym *near = NULL; + Elf64_Sword distance = 20; + Elf64_Sword d; + + if (relsym->st_name != 0) + return relsym; + for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { + if (sym->st_shndx != relsym->st_shndx) + continue; + if (ELF_ST_TYPE(sym->st_info) == STT_SECTION) + continue; + if (sym->st_value == addr) + return sym; + /* Find a symbol nearby - addr are maybe negative */ + d = sym->st_value - addr; + if (d < 0) + d = addr - sym->st_value; + if (d < distance) { + distance = d; + near = sym; + } + } + /* We need a close match */ + if (distance < 20) + return near; + else + return NULL; +} + +static inline int is_arm_mapping_symbol(const char *str) +{ + return str[0] == '$' && strchr("atd", str[1]) + && (str[2] == '\0' || str[2] == '.'); +} + +/* + * If there's no name there, ignore it; likewise, ignore it if it's + * one of the magic symbols emitted used by current ARM tools. + * + * Otherwise if find_symbols_between() returns those symbols, they'll + * fail the whitelist tests and cause lots of false alarms ... fixable + * only by merging __exit and __init sections into __text, bloating + * the kernel (which is especially evil on embedded platforms). + */ +static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym) +{ + const char *name = elf->strtab + sym->st_name; + + if (!name || !strlen(name)) + return 0; + return !is_arm_mapping_symbol(name); +} + +/* + * Find symbols before or equal addr and after addr - in the section sec. + * If we find two symbols with equal offset prefer one with a valid name. + * The ELF format may have a better way to detect what type of symbol + * it is, but this works for now. + **/ +static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr, + const char *sec) +{ + Elf_Sym *sym; + Elf_Sym *near = NULL; + Elf_Addr distance = ~0; + + for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { + const char *symsec; + + if (sym->st_shndx >= SHN_LORESERVE) + continue; + symsec = sec_name(elf, sym->st_shndx); + if (strcmp(symsec, sec) != 0) + continue; + if (!is_valid_name(elf, sym)) + continue; + if (sym->st_value <= addr) { + if ((addr - sym->st_value) < distance) { + distance = addr - sym->st_value; + near = sym; + } else if ((addr - sym->st_value) == distance) { + near = sym; + } + } + } + return near; +} + +/* + * Convert a section name to the function/data attribute + * .init.text => __init + * .cpuinit.data => __cpudata + * .memexitconst => __memconst + * etc. +*/ +static char *sec2annotation(const char *s) +{ + if (match(s, init_exit_sections)) { + char *p = malloc(20); + char *r = p; + + *p++ = '_'; + *p++ = '_'; + if (*s == '.') + s++; + while (*s && *s != '.') + *p++ = *s++; + *p = '\0'; + if (*s == '.') + s++; + if (strstr(s, "rodata") != NULL) + strcat(p, "const "); + else if (strstr(s, "data") != NULL) + strcat(p, "data "); + else + strcat(p, " "); + return r; /* we leak her but we do not care */ + } else { + return ""; + } +} + +static int is_function(Elf_Sym *sym) +{ + if (sym) + return ELF_ST_TYPE(sym->st_info) == STT_FUNC; + else + return -1; +} + +/* + * Print a warning about a section mismatch. + * Try to find symbols near it so user can find it. + * Check whitelist before warning - it may be a false positive. + */ +static void report_sec_mismatch(const char *modname, enum mismatch mismatch, + const char *fromsec, + unsigned long long fromaddr, + const char *fromsym, + int from_is_func, + const char *tosec, const char *tosym, + int to_is_func) +{ + const char *from, *from_p; + const char *to, *to_p; + + switch (from_is_func) { + case 0: from = "variable"; from_p = ""; break; + case 1: from = "function"; from_p = "()"; break; + default: from = "(unknown reference)"; from_p = ""; break; + } + switch (to_is_func) { + case 0: to = "variable"; to_p = ""; break; + case 1: to = "function"; to_p = "()"; break; + default: to = "(unknown reference)"; to_p = ""; break; + } + + sec_mismatch_count++; + if (!sec_mismatch_verbose) + return; + + warn("%s(%s+0x%llx): Section mismatch in reference from the %s %s%s " + "to the %s %s:%s%s\n", + modname, fromsec, fromaddr, from, fromsym, from_p, to, tosec, + tosym, to_p); + + switch (mismatch) { + case TEXT_TO_INIT: + fprintf(stderr, + "The function %s%s() references\n" + "the %s %s%s%s.\n" + "This is often because %s lacks a %s\n" + "annotation or the annotation of %s is wrong.\n", + sec2annotation(fromsec), fromsym, + to, sec2annotation(tosec), tosym, to_p, + fromsym, sec2annotation(tosec), tosym); + break; + case DATA_TO_INIT: { + const char **s = symbol_white_list; + fprintf(stderr, + "The variable %s references\n" + "the %s %s%s%s\n" + "If the reference is valid then annotate the\n" + "variable with __init* or __refdata (see linux/init.h) " + "or name the variable:\n", + fromsym, to, sec2annotation(tosec), tosym, to_p); + while (*s) + fprintf(stderr, "%s, ", *s++); + fprintf(stderr, "\n"); + break; + } + case TEXT_TO_EXIT: + fprintf(stderr, + "The function %s() references a %s in an exit section.\n" + "Often the %s %s%s has valid usage outside the exit section\n" + "and the fix is to remove the %sannotation of %s.\n", + fromsym, to, to, tosym, to_p, sec2annotation(tosec), tosym); + break; + case DATA_TO_EXIT: { + const char **s = symbol_white_list; + fprintf(stderr, + "The variable %s references\n" + "the %s %s%s%s\n" + "If the reference is valid then annotate the\n" + "variable with __exit* (see linux/init.h) or " + "name the variable:\n", + fromsym, to, sec2annotation(tosec), tosym, to_p); + while (*s) + fprintf(stderr, "%s, ", *s++); + fprintf(stderr, "\n"); + break; + } + case XXXINIT_TO_INIT: + case XXXEXIT_TO_EXIT: + fprintf(stderr, + "The %s %s%s%s references\n" + "a %s %s%s%s.\n" + "If %s is only used by %s then\n" + "annotate %s with a matching annotation.\n", + from, sec2annotation(fromsec), fromsym, from_p, + to, sec2annotation(tosec), tosym, to_p, + tosym, fromsym, tosym); + break; + case INIT_TO_EXIT: + fprintf(stderr, + "The %s %s%s%s references\n" + "a %s %s%s%s.\n" + "This is often seen when error handling " + "in the init function\n" + "uses functionality in the exit path.\n" + "The fix is often to remove the %sannotation of\n" + "%s%s so it may be used outside an exit section.\n", + from, sec2annotation(fromsec), fromsym, from_p, + to, sec2annotation(tosec), tosym, to_p, + sec2annotation(tosec), tosym, to_p); + break; + case EXIT_TO_INIT: + fprintf(stderr, + "The %s %s%s%s references\n" + "a %s %s%s%s.\n" + "This is often seen when error handling " + "in the exit function\n" + "uses functionality in the init path.\n" + "The fix is often to remove the %sannotation of\n" + "%s%s so it may be used outside an init section.\n", + from, sec2annotation(fromsec), fromsym, from_p, + to, sec2annotation(tosec), tosym, to_p, + sec2annotation(tosec), tosym, to_p); + break; + case EXPORT_TO_INIT_EXIT: + fprintf(stderr, + "The symbol %s is exported and annotated %s\n" + "Fix this by removing the %sannotation of %s " + "or drop the export.\n", + tosym, sec2annotation(tosec), sec2annotation(tosec), tosym); + case NO_MISMATCH: + /* To get warnings on missing members */ + break; + } + fprintf(stderr, "\n"); +} + +static void check_section_mismatch(const char *modname, struct elf_info *elf, + Elf_Rela *r, Elf_Sym *sym, const char *fromsec) +{ + const char *tosec; + enum mismatch mismatch; + + tosec = sec_name(elf, sym->st_shndx); + mismatch = section_mismatch(fromsec, tosec); + if (mismatch != NO_MISMATCH) { + Elf_Sym *to; + Elf_Sym *from; + const char *tosym; + const char *fromsym; + + from = find_elf_symbol2(elf, r->r_offset, fromsec); + fromsym = sym_name(elf, from); + to = find_elf_symbol(elf, r->r_addend, sym); + tosym = sym_name(elf, to); + + /* check whitelist - we may ignore it */ + if (secref_whitelist(fromsec, fromsym, tosec, tosym)) { + report_sec_mismatch(modname, mismatch, + fromsec, r->r_offset, fromsym, + is_function(from), tosec, tosym, + is_function(to)); + } + } +} + +static unsigned int *reloc_location(struct elf_info *elf, + Elf_Shdr *sechdr, Elf_Rela *r) +{ + Elf_Shdr *sechdrs = elf->sechdrs; + int section = sechdr->sh_info; + + return (void *)elf->hdr + sechdrs[section].sh_offset + + (r->r_offset - sechdrs[section].sh_addr); +} + +static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) +{ + unsigned int r_typ = ELF_R_TYPE(r->r_info); + unsigned int *location = reloc_location(elf, sechdr, r); + + switch (r_typ) { + case R_386_32: + r->r_addend = TO_NATIVE(*location); + break; + case R_386_PC32: + r->r_addend = TO_NATIVE(*location) + 4; + /* For CONFIG_RELOCATABLE=y */ + if (elf->hdr->e_type == ET_EXEC) + r->r_addend += r->r_offset; + break; + } + return 0; +} + +static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) +{ + unsigned int r_typ = ELF_R_TYPE(r->r_info); + + switch (r_typ) { + case R_ARM_ABS32: + /* From ARM ABI: (S + A) | T */ + r->r_addend = (int)(long) + (elf->symtab_start + ELF_R_SYM(r->r_info)); + break; + case R_ARM_PC24: + /* From ARM ABI: ((S + A) | T) - P */ + r->r_addend = (int)(long)(elf->hdr + + sechdr->sh_offset + + (r->r_offset - sechdr->sh_addr)); + break; + default: + return 1; + } + return 0; +} + +static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) +{ + unsigned int r_typ = ELF_R_TYPE(r->r_info); + unsigned int *location = reloc_location(elf, sechdr, r); + unsigned int inst; + + if (r_typ == R_MIPS_HI16) + return 1; /* skip this */ + inst = TO_NATIVE(*location); + switch (r_typ) { + case R_MIPS_LO16: + r->r_addend = inst & 0xffff; + break; + case R_MIPS_26: + r->r_addend = (inst & 0x03ffffff) << 2; + break; + case R_MIPS_32: + r->r_addend = inst; + break; + } + return 0; +} + +static void section_rela(const char *modname, struct elf_info *elf, + Elf_Shdr *sechdr) +{ + Elf_Sym *sym; + Elf_Rela *rela; + Elf_Rela r; + unsigned int r_sym; + const char *fromsec; + + Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset; + Elf_Rela *stop = (void *)start + sechdr->sh_size; + + fromsec = sech_name(elf, sechdr); + fromsec += strlen(".rela"); + /* if from section (name) is know good then skip it */ + if (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 (sym->st_shndx >= SHN_LORESERVE) + continue; + check_section_mismatch(modname, elf, &r, sym, fromsec); + } +} + +static void section_rel(const char *modname, struct elf_info *elf, + Elf_Shdr *sechdr) +{ + Elf_Sym *sym; + Elf_Rel *rel; + Elf_Rela r; + unsigned int r_sym; + const char *fromsec; + + Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset; + Elf_Rel *stop = (void *)start + sechdr->sh_size; + + fromsec = sech_name(elf, sechdr); + fromsec += strlen(".rel"); + /* if from section (name) is know good then skip it */ + if (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 (sym->st_shndx >= SHN_LORESERVE) + continue; + check_section_mismatch(modname, elf, &r, sym, fromsec); + } +} + +/** + * A module includes a number of sections that are discarded + * either when loaded or when used as built-in. + * For loaded modules all functions marked __init and all data + * marked __initdata will be discarded when the module has been intialized. + * Likewise for modules used built-in the sections marked __exit + * are discarded because __exit marked function are supposed to be called + * only when a 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->hdr->e_shnum; 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 void read_symbols(char *modname) { const char *symname; char *version; + char *license; struct module *mod; struct elf_info info = { }; Elf_Sym *sym; - parse_elf(&info, modname); + if (!parse_elf(&info, modname)) + return; mod = new_module(modname); /* When there's no vmlinux, don't print warnings about * unresolved symbols (since there'll be too many ;) */ if (is_vmlinux(modname)) { - unsigned int fake_crc = 0; have_vmlinux = 1; - add_exported_symbol("struct_module", mod, &fake_crc); mod->skip = 1; } + license = get_modinfo(info.modinfo, info.modinfo_len, "license"); + if (info.modinfo && !license && !is_vmlinux(modname)) + warn("modpost: missing MODULE_LICENSE() in %s\n" + "see include/linux/module.h for " + "more information\n", modname); + while (license) { + if (license_is_gpl_compatible(license)) + mod->gpl_compatible = 1; + else { + mod->gpl_compatible = 0; + break; + } + license = get_next_modinfo(info.modinfo, info.modinfo_len, + "license", license); + } + for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { symname = info.strtab + sym->st_name; handle_modversions(mod, &info, sym, symname); handle_moddevtable(mod, &info, sym, symname); } + if (!is_vmlinux(modname) || + (is_vmlinux(modname) && vmlinux_section_warnings)) + check_sec_ref(mod, modname, &info); version = get_modinfo(info.modinfo, info.modinfo_len, "version"); if (version) @@ -485,12 +1573,12 @@ read_symbols(char *modname) parse_elf_finish(&info); - /* Our trick to get versioning for struct_module - it's + /* 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("struct_module", 0, mod->unres); + mod->unres = alloc_symbol("module_layout", 0, mod->unres); } #define SZ 500 @@ -499,39 +1587,94 @@ read_symbols(char *modname) * following helper, then compare to the file on disk and * only update the later if anything changed */ -void __attribute__((format(printf, 2, 3))) -buf_printf(struct buffer *buf, const char *fmt, ...) +void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf, + const char *fmt, ...) { char tmp[SZ]; int len; va_list ap; - + va_start(ap, fmt); len = vsnprintf(tmp, SZ, fmt, ap); - if (buf->size - buf->pos < len + 1) { - buf->size += 128; - buf->p = realloc(buf->p, buf->size); - } - strncpy(buf->p + buf->pos, tmp, len + 1); - buf->pos += len; + buf_write(buf, tmp, len); va_end(ap); } -void -buf_write(struct buffer *buf, const char *s, int len) +void buf_write(struct buffer *buf, const char *s, int len) { if (buf->size - buf->pos < len) { - buf->size += len; + buf->size += len + SZ; buf->p = realloc(buf->p, buf->size); } strncpy(buf->p + buf->pos, s, len); buf->pos += len; } -/* Header for the generated file */ +static void check_for_gpl_usage(enum export exp, const char *m, const char *s) +{ + const char *e = is_vmlinux(m) ?"":".ko"; + + switch (exp) { + case export_gpl: + fatal("modpost: GPL-incompatible module %s%s " + "uses GPL-only symbol '%s'\n", m, e, s); + break; + case export_unused_gpl: + fatal("modpost: GPL-incompatible module %s%s " + "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s); + break; + case export_gpl_future: + warn("modpost: GPL-incompatible module %s%s " + "uses future GPL-only symbol '%s'\n", m, e, s); + break; + case export_plain: + case export_unused: + case export_unknown: + /* ignore */ + break; + } +} + +static void check_for_unused(enum export exp, const char *m, const char *s) +{ + const char *e = is_vmlinux(m) ?"":".ko"; + + switch (exp) { + case export_unused: + case export_unused_gpl: + warn("modpost: module %s%s " + "uses symbol '%s' marked UNUSED\n", m, e, s); + break; + default: + /* ignore */ + break; + } +} + +static void check_exports(struct module *mod) +{ + struct symbol *s, *exp; + + for (s = mod->unres; s; s = s->next) { + const char *basename; + exp = find_symbol(s->name); + if (!exp || exp->module == mod) + continue; + basename = strrchr(mod->name, '/'); + if (basename) + basename++; + else + basename = mod->name; + if (!mod->gpl_compatible) + check_for_gpl_usage(exp->export, basename, exp->name); + check_for_unused(exp->export, basename, exp->name); + } +} -void -add_header(struct buffer *b, struct module *mod) +/** + * Header for the generated file + **/ +static void add_header(struct buffer *b, struct module *mod) { buf_printf(b, "#include \n"); buf_printf(b, "#include \n"); @@ -539,32 +1682,48 @@ add_header(struct buffer *b, struct module *mod) buf_printf(b, "\n"); buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n"); buf_printf(b, "\n"); - buf_printf(b, "#undef unix\n"); /* We have a module called "unix" */ buf_printf(b, "struct module __this_module\n"); buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n"); - buf_printf(b, " .name = __stringify(KBUILD_MODNAME),\n"); + buf_printf(b, " .name = KBUILD_MODNAME,\n"); if (mod->has_init) buf_printf(b, " .init = init_module,\n"); if (mod->has_cleanup) buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n" " .exit = cleanup_module,\n" "#endif\n"); + buf_printf(b, " .arch = MODULE_ARCH_INIT,\n"); buf_printf(b, "};\n"); } -/* Record CRCs for unresolved symbols */ +static void add_staging_flag(struct buffer *b, const char *name) +{ + static const char *staging_dir = "drivers/staging"; + + if (strncmp(staging_dir, name, strlen(staging_dir)) == 0) + buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); +} -void -add_versions(struct buffer *b, struct module *mod) +/** + * Record CRCs for unresolved symbols + **/ +static int add_versions(struct buffer *b, struct module *mod) { struct symbol *s, *exp; + int err = 0; for (s = mod->unres; s; s = s->next) { exp = find_symbol(s->name); if (!exp || exp->module == mod) { - if (have_vmlinux && !s->weak) - fprintf(stderr, "*** Warning: \"%s\" [%s.ko] " - "undefined!\n", s->name, mod->name); + if (have_vmlinux && !s->weak) { + if (warn_unresolved) { + warn("\"%s\" [%s.ko] undefined!\n", + s->name, mod->name); + } else { + merror("\"%s\" [%s.ko] undefined!\n", + s->name, mod->name); + err = 1; + } + } continue; } s->module = exp->module; @@ -573,20 +1732,18 @@ add_versions(struct buffer *b, struct module *mod) } if (!modversions) - return; + return err; buf_printf(b, "\n"); buf_printf(b, "static const struct modversion_info ____versions[]\n"); - buf_printf(b, "__attribute_used__\n"); + buf_printf(b, "__used\n"); buf_printf(b, "__attribute__((section(\"__versions\"))) = {\n"); for (s = mod->unres; s; s = s->next) { - if (!s->module) { + if (!s->module) continue; - } if (!s->crc_valid) { - fprintf(stderr, "*** Warning: \"%s\" [%s.ko] " - "has no CRC!\n", + warn("\"%s\" [%s.ko] has no CRC!\n", s->name, mod->name); continue; } @@ -594,25 +1751,27 @@ add_versions(struct buffer *b, struct module *mod) } buf_printf(b, "};\n"); + + return err; } -void -add_depends(struct buffer *b, struct module *mod, struct module *modules) +static void add_depends(struct buffer *b, struct module *mod, + struct module *modules) { struct symbol *s; struct module *m; int first = 1; - for (m = modules; m; m = m->next) { + for (m = modules; m; m = m->next) m->seen = is_vmlinux(m->name); - } buf_printf(b, "\n"); buf_printf(b, "static const char __module_depends[]\n"); - buf_printf(b, "__attribute_used__\n"); + buf_printf(b, "__used\n"); buf_printf(b, "__attribute__((section(\".modinfo\"))) =\n"); buf_printf(b, "\"depends="); for (s = mod->unres; s; s = s->next) { + const char *p; if (!s->module) continue; @@ -620,15 +1779,18 @@ add_depends(struct buffer *b, struct module *mod, struct module *modules) continue; s->module->seen = 1; - buf_printf(b, "%s%s", first ? "" : ",", - strrchr(s->module->name, '/') + 1); + p = strrchr(s->module->name, '/'); + if (p) + p++; + else + p = s->module->name; + buf_printf(b, "%s%s", first ? "" : ",", p); first = 0; } buf_printf(b, "\";\n"); } -void -add_srcversion(struct buffer *b, struct module *mod) +static void add_srcversion(struct buffer *b, struct module *mod) { if (mod->srcversion[0]) { buf_printf(b, "\n"); @@ -637,8 +1799,7 @@ add_srcversion(struct buffer *b, struct module *mod) } } -void -write_if_changed(struct buffer *b, const char *fname) +static void write_if_changed(struct buffer *b, const char *fname) { char *tmp; FILE *file; @@ -682,21 +1843,24 @@ write_if_changed(struct buffer *b, const char *fname) fclose(file); } -void -read_dump(const char *fname) +/* parse Module.symvers file. line format: + * 0x12345678symbolmodule[[export]something] + **/ +static void read_dump(const char *fname, unsigned int kernel) { unsigned long size, pos = 0; void *file = grab_file(fname, &size); char *line; - if (!file) + if (!file) /* No symbol versions, silently ignore */ return; while ((line = get_next_line(&pos, file, size))) { - char *symname, *modname, *d; + char *symname, *modname, *d, *export, *end; unsigned int crc; struct module *mod; + struct symbol *s; if (!(symname = strchr(line, '\t'))) goto fail; @@ -704,28 +1868,44 @@ read_dump(const char *fname) if (!(modname = strchr(symname, '\t'))) goto fail; *modname++ = '\0'; - if (strchr(modname, '\t')) - goto fail; + if ((export = strchr(modname, '\t')) != NULL) + *export++ = '\0'; + if (export && ((end = strchr(export, '\t')) != NULL)) + *end = '\0'; crc = strtoul(line, &d, 16); if (*symname == '\0' || *modname == '\0' || *d != '\0') goto fail; - - if (!(mod = find_module(modname))) { - if (is_vmlinux(modname)) { + mod = find_module(modname); + if (!mod) { + if (is_vmlinux(modname)) have_vmlinux = 1; - } - mod = new_module(NOFAIL(strdup(modname))); + mod = new_module(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; @@ -734,64 +1914,109 @@ write_dump(const char *fname) 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) +struct ext_sym_list { + struct ext_sym_list *next; + const char *file; +}; + +int main(int argc, char **argv) { struct module *mod; struct buffer buf = { }; - char fname[SZ]; - char *dump_read = NULL, *dump_write = NULL; + char *kernel_read = NULL, *module_read = NULL; + char *dump_write = NULL; int opt; - - while ((opt = getopt(argc, argv, "i:mo:a")) != -1) { - switch(opt) { - case 'i': - dump_read = optarg; - break; - case 'm': - modversions = 1; - break; - case 'o': - dump_write = optarg; - break; - case 'a': - all_versions = 1; - break; - default: - exit(1); + int err; + struct ext_sym_list *extsym_iter; + struct ext_sym_list *extsym_start = NULL; + + while ((opt = getopt(argc, argv, "i:I:e:cmsSo:awM:K:")) != -1) { + switch (opt) { + case 'i': + kernel_read = optarg; + break; + case 'I': + module_read = optarg; + external_module = 1; + break; + case 'c': + cross_build = 1; + break; + case 'e': + external_module = 1; + extsym_iter = + NOFAIL(malloc(sizeof(*extsym_iter))); + extsym_iter->next = extsym_start; + extsym_iter->file = optarg; + extsym_start = extsym_iter; + break; + case 'm': + modversions = 1; + break; + case 'o': + dump_write = optarg; + break; + case 'a': + all_versions = 1; + break; + case 's': + vmlinux_section_warnings = 0; + break; + case 'S': + sec_mismatch_verbose = 0; + break; + case 'w': + warn_unresolved = 1; + break; + default: + exit(1); } } - if (dump_read) - read_dump(dump_read); + if (kernel_read) + read_dump(kernel_read, 1); + if (module_read) + read_dump(module_read, 0); + while (extsym_start) { + read_dump(extsym_start->file, 0); + extsym_iter = extsym_start->next; + free(extsym_start); + extsym_start = extsym_iter; + } - while (optind < argc) { + while (optind < argc) read_symbols(argv[optind++]); + + for (mod = modules; mod; mod = mod->next) { + if (mod->skip) + continue; + check_exports(mod); } + err = 0; + for (mod = modules; mod; mod = mod->next) { + char fname[strlen(mod->name) + 10]; + if (mod->skip) continue; buf.pos = 0; add_header(&buf, mod); - add_versions(&buf, mod); + add_staging_flag(&buf, mod->name); + err |= add_versions(&buf, mod); add_depends(&buf, mod, modules); add_moddevtable(&buf, mod); add_srcversion(&buf, mod); @@ -802,7 +2027,11 @@ main(int argc, char **argv) if (dump_write) write_dump(dump_write); + if (sec_mismatch_count && !sec_mismatch_verbose) + warn("modpost: Found %d section mismatch(es).\n" + "To see full details build your kernel with:\n" + "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n", + sec_mismatch_count); - return 0; + return err; } -