X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fmodule.c;h=3202c9950073ebc05fb232a625da27d2ec35eee8;hb=907135aaa0cc120a347222c8f274ecc5ca0db641;hp=015d60cfd90e4f67f07380fac6c05d44aec81580;hpb=e030dbf91a87da7e8be3be3ca781558695bea683;p=linux-2.6 diff --git a/kernel/module.c b/kernel/module.c index 015d60cfd9..3202c99500 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -61,10 +62,8 @@ extern int module_sysfs_initialized; /* If this is set, the section belongs in the init part of the module */ #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) -/* Protects module list */ -static DEFINE_SPINLOCK(modlist_lock); - -/* List of modules, protected by module_mutex AND modlist_lock */ +/* List of modules, protected by module_mutex or preempt_disable + * (add/delete uses stop_machine). */ static DEFINE_MUTEX(module_mutex); static LIST_HEAD(modules); @@ -106,7 +105,7 @@ void __module_put_and_exit(struct module *mod, long code) do_exit(code); } EXPORT_SYMBOL(__module_put_and_exit); - + /* Find a module section: 0 means not found. */ static unsigned int find_sec(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, @@ -180,7 +179,7 @@ static unsigned long __find_symbol(const char *name, struct module *mod; const struct kernel_symbol *ks; - /* Core kernel first. */ + /* Core kernel first. */ *owner = NULL; ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab); if (ks) { @@ -232,7 +231,7 @@ static unsigned long __find_symbol(const char *name, return ks->value; } - /* Now try modules. */ + /* Now try modules. */ list_for_each_entry(mod, &modules, list) { *owner = mod; ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms); @@ -286,7 +285,7 @@ static unsigned long __find_symbol(const char *name, } } DEBUGP("Failed to find symbol %s\n", name); - return 0; + return 0; } /* Search for module by name: must hold module_mutex. */ @@ -442,7 +441,7 @@ static int percpu_modinit(void) } return 0; -} +} __initcall(percpu_modinit); #else /* ... !CONFIG_SMP */ static inline void *percpu_modalloc(unsigned long size, unsigned long align, @@ -484,8 +483,8 @@ static int modinfo_##field##_exists(struct module *mod) \ } \ static void free_modinfo_##field(struct module *mod) \ { \ - kfree(mod->field); \ - mod->field = NULL; \ + kfree(mod->field); \ + mod->field = NULL; \ } \ static struct module_attribute modinfo_##field = { \ .attr = { .name = __stringify(field), .mode = 0444 }, \ @@ -694,8 +693,7 @@ sys_delete_module(const char __user *name_user, unsigned int flags) } /* If it has an init func, it must have an exit func to unload */ - if ((mod->init != NULL && mod->exit == NULL) - || mod->unsafe) { + if (mod->init && !mod->exit) { forced = try_force_unload(flags); if (!forced) { /* This module can't be removed */ @@ -743,11 +741,6 @@ static void print_unload_info(struct seq_file *m, struct module *mod) seq_printf(m, "%s,", use->module_which_uses->name); } - if (mod->unsafe) { - printed_something = 1; - seq_printf(m, "[unsafe],"); - } - if (mod->init != NULL && mod->exit == NULL) { printed_something = 1; seq_printf(m, "[permanent],"); @@ -760,14 +753,13 @@ static void print_unload_info(struct seq_file *m, struct module *mod) void __symbol_put(const char *symbol) { struct module *owner; - unsigned long flags; const unsigned long *crc; - spin_lock_irqsave(&modlist_lock, flags); + preempt_disable(); if (!__find_symbol(symbol, &owner, &crc, 1)) BUG(); module_put(owner); - spin_unlock_irqrestore(&modlist_lock, flags); + preempt_enable(); } EXPORT_SYMBOL(__symbol_put); @@ -787,8 +779,7 @@ EXPORT_SYMBOL_GPL(symbol_put_addr); static ssize_t show_refcnt(struct module_attribute *mattr, struct module *mod, char *buffer) { - /* sysfs holds a reference */ - return sprintf(buffer, "%u\n", module_refcount(mod)-1); + return sprintf(buffer, "%u\n", module_refcount(mod)); } static struct module_attribute refcnt = { @@ -999,7 +990,7 @@ static void add_sect_attrs(struct module *mod, unsigned int nsect, struct module_sect_attrs *sect_attrs; struct module_sect_attr *sattr; struct attribute **gattr; - + /* Count loaded sections and allocate structures */ for (i = 0; i < nsect; i++) if (sechdrs[i].sh_flags & SHF_ALLOC) @@ -1057,6 +1048,100 @@ static void remove_sect_attrs(struct module *mod) } } +/* + * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections. + */ + +struct module_notes_attrs { + struct kobject *dir; + unsigned int notes; + struct bin_attribute attrs[0]; +}; + +static ssize_t module_notes_read(struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t pos, size_t count) +{ + /* + * The caller checked the pos and count against our size. + */ + memcpy(buf, bin_attr->private + pos, count); + return count; +} + +static void free_notes_attrs(struct module_notes_attrs *notes_attrs, + unsigned int i) +{ + if (notes_attrs->dir) { + while (i-- > 0) + sysfs_remove_bin_file(notes_attrs->dir, + ¬es_attrs->attrs[i]); + kobject_del(notes_attrs->dir); + } + kfree(notes_attrs); +} + +static void add_notes_attrs(struct module *mod, unsigned int nsect, + char *secstrings, Elf_Shdr *sechdrs) +{ + unsigned int notes, loaded, i; + struct module_notes_attrs *notes_attrs; + struct bin_attribute *nattr; + + /* Count notes sections and allocate structures. */ + notes = 0; + for (i = 0; i < nsect; i++) + if ((sechdrs[i].sh_flags & SHF_ALLOC) && + (sechdrs[i].sh_type == SHT_NOTE)) + ++notes; + + if (notes == 0) + return; + + notes_attrs = kzalloc(sizeof(*notes_attrs) + + notes * sizeof(notes_attrs->attrs[0]), + GFP_KERNEL); + if (notes_attrs == NULL) + return; + + notes_attrs->notes = notes; + nattr = ¬es_attrs->attrs[0]; + for (loaded = i = 0; i < nsect; ++i) { + if (!(sechdrs[i].sh_flags & SHF_ALLOC)) + continue; + if (sechdrs[i].sh_type == SHT_NOTE) { + nattr->attr.name = mod->sect_attrs->attrs[loaded].name; + nattr->attr.mode = S_IRUGO; + nattr->size = sechdrs[i].sh_size; + nattr->private = (void *) sechdrs[i].sh_addr; + nattr->read = module_notes_read; + ++nattr; + } + ++loaded; + } + + notes_attrs->dir = kobject_add_dir(&mod->mkobj.kobj, "notes"); + if (!notes_attrs->dir) + goto out; + + for (i = 0; i < notes; ++i) + if (sysfs_create_bin_file(notes_attrs->dir, + ¬es_attrs->attrs[i])) + goto out; + + mod->notes_attrs = notes_attrs; + return; + + out: + free_notes_attrs(notes_attrs, i); +} + +static void remove_notes_attrs(struct module *mod) +{ + if (mod->notes_attrs) + free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes); +} + #else static inline void add_sect_attrs(struct module *mod, unsigned int nsect, @@ -1067,6 +1152,15 @@ static inline void add_sect_attrs(struct module *mod, unsigned int nsect, static inline void remove_sect_attrs(struct module *mod) { } + +static inline void add_notes_attrs(struct module *mod, unsigned int nsect, + char *sectstrings, Elf_Shdr *sechdrs) +{ +} + +static inline void remove_notes_attrs(struct module *mod) +{ +} #endif /* CONFIG_KALLSYMS */ #ifdef CONFIG_SYSFS @@ -1201,6 +1295,7 @@ static void free_module(struct module *mod) { /* Delete from various lists */ stop_machine_run(__unlink_module, mod, NR_CPUS); + remove_notes_attrs(mod); remove_sect_attrs(mod); mod_kobject_remove(mod); @@ -1228,14 +1323,14 @@ static void free_module(struct module *mod) void *__symbol_get(const char *symbol) { struct module *owner; - unsigned long value, flags; + unsigned long value; const unsigned long *crc; - spin_lock_irqsave(&modlist_lock, flags); + preempt_disable(); value = __find_symbol(symbol, &owner, &crc, 1); if (value && !strong_try_module_get(owner)) value = 0; - spin_unlock_irqrestore(&modlist_lock, flags); + preempt_enable(); return (void *)value; } @@ -1253,14 +1348,14 @@ static int verify_export_symbols(struct module *mod) const unsigned long *crc; for (i = 0; i < mod->num_syms; i++) - if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) { + if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) { name = mod->syms[i].name; ret = -ENOEXEC; goto dup; } for (i = 0; i < mod->num_gpl_syms; i++) - if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) { + if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) { name = mod->gpl_syms[i].name; ret = -ENOEXEC; goto dup; @@ -1578,6 +1673,8 @@ static struct module *load_module(void __user *umod, unsigned int unusedcrcindex; unsigned int unusedgplindex; unsigned int unusedgplcrcindex; + unsigned int markersindex; + unsigned int markersstringsindex; struct module *mod; long err = 0; void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */ @@ -1786,7 +1883,8 @@ static struct module *load_module(void __user *umod, module_unload_init(mod); /* Initialize kobject, so we can reference it. */ - if (mod_sysfs_init(mod) != 0) + err = mod_sysfs_init(mod); + if (err) goto cleanup; /* Set up license info based on the info section */ @@ -1833,7 +1931,7 @@ static struct module *load_module(void __user *umod, mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr; #ifdef CONFIG_MODVERSIONS - if ((mod->num_syms && !crcindex) || + if ((mod->num_syms && !crcindex) || (mod->num_gpl_syms && !gplcrcindex) || (mod->num_gpl_future_syms && !gplfuturecrcindex) || (mod->num_unused_syms && !unusedcrcindex) || @@ -1843,6 +1941,9 @@ static struct module *load_module(void __user *umod, add_taint_module(mod, TAINT_FORCED_MODULE); } #endif + markersindex = find_sec(hdr, sechdrs, secstrings, "__markers"); + markersstringsindex = find_sec(hdr, sechdrs, secstrings, + "__markers_strings"); /* Now do relocations. */ for (i = 1; i < hdr->e_shnum; i++) { @@ -1865,6 +1966,11 @@ static struct module *load_module(void __user *umod, if (err < 0) goto cleanup; } +#ifdef CONFIG_MARKERS + mod->markers = (void *)sechdrs[markersindex].sh_addr; + mod->num_markers = + sechdrs[markersindex].sh_size / sizeof(*mod->markers); +#endif /* Find duplicate symbols */ err = verify_export_symbols(mod); @@ -1883,6 +1989,11 @@ static struct module *load_module(void __user *umod, add_kallsyms(mod, sechdrs, symindex, strindex, secstrings); +#ifdef CONFIG_MARKERS + if (!mod->taints) + marker_update_probe_range(mod->markers, + mod->markers + mod->num_markers, NULL, NULL); +#endif err = module_finalize(hdr, sechdrs, mod); if (err < 0) goto cleanup; @@ -1920,7 +2031,7 @@ static struct module *load_module(void __user *umod, if (err < 0) goto arch_cleanup; - err = mod_sysfs_setup(mod, + err = mod_sysfs_setup(mod, (struct kernel_param *) sechdrs[setupindex].sh_addr, sechdrs[setupindex].sh_size @@ -1928,11 +2039,12 @@ static struct module *load_module(void __user *umod, if (err < 0) goto arch_cleanup; add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs); + add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs); /* Size of section 0 is 0, so this works well if no unwind info. */ mod->unwind_info = unwind_add_table(mod, - (void *)sechdrs[unwindex].sh_addr, - sechdrs[unwindex].sh_size); + (void *)sechdrs[unwindex].sh_addr, + sechdrs[unwindex].sh_size); /* Get rid of temporary copy */ vfree(hdr); @@ -2015,15 +2127,10 @@ sys_init_module(void __user *umod, buggy refcounters. */ mod->state = MODULE_STATE_GOING; synchronize_sched(); - if (mod->unsafe) - printk(KERN_ERR "%s: module is now stuck!\n", - mod->name); - else { - module_put(mod); - mutex_lock(&module_mutex); - free_module(mod); - mutex_unlock(&module_mutex); - } + module_put(mod); + mutex_lock(&module_mutex); + free_module(mod); + mutex_unlock(&module_mutex); return ret; } @@ -2054,7 +2161,7 @@ static inline int within(unsigned long addr, void *start, unsigned long size) */ static inline int is_arm_mapping_symbol(const char *str) { - return str[0] == '$' && strchr("atd", str[1]) + return str[0] == '$' && strchr("atd", str[1]) && (str[2] == '\0' || str[2] == '.'); } @@ -2069,11 +2176,11 @@ static const char *get_ksymbol(struct module *mod, /* At worse, next value is at end of module */ if (within(addr, mod->module_init, mod->init_size)) nextval = (unsigned long)mod->module_init+mod->init_text_size; - else + else nextval = (unsigned long)mod->module_core+mod->core_text_size; /* Scan for closest preceeding symbol, and next symbol. (ELF - starts real symbols at 1). */ + starts real symbols at 1). */ for (i = 1; i < mod->num_symtab; i++) { if (mod->symtab[i].st_shndx == SHN_UNDEF) continue; @@ -2136,7 +2243,7 @@ int lookup_module_symbol_name(unsigned long addr, char *symname) sym = get_ksymbol(mod, addr, NULL, NULL); if (!sym) goto out; - strlcpy(symname, sym, KSYM_NAME_LEN + 1); + strlcpy(symname, sym, KSYM_NAME_LEN); mutex_unlock(&module_mutex); return 0; } @@ -2161,9 +2268,9 @@ int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, if (!sym) goto out; if (modname) - strlcpy(modname, mod->name, MODULE_NAME_LEN + 1); + strlcpy(modname, mod->name, MODULE_NAME_LEN); if (name) - strlcpy(name, sym, KSYM_NAME_LEN + 1); + strlcpy(name, sym, KSYM_NAME_LEN); mutex_unlock(&module_mutex); return 0; } @@ -2184,8 +2291,8 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, *value = mod->symtab[symnum].st_value; *type = mod->symtab[symnum].st_info; strlcpy(name, mod->strtab + mod->symtab[symnum].st_name, - KSYM_NAME_LEN + 1); - strlcpy(module_name, mod->name, MODULE_NAME_LEN + 1); + KSYM_NAME_LEN); + strlcpy(module_name, mod->name, MODULE_NAME_LEN); *exported = is_exported(name, mod); mutex_unlock(&module_mutex); return 0; @@ -2232,26 +2339,13 @@ unsigned long module_kallsyms_lookup_name(const char *name) /* Called by the /proc file system to return a list of modules. */ static void *m_start(struct seq_file *m, loff_t *pos) { - struct list_head *i; - loff_t n = 0; - mutex_lock(&module_mutex); - list_for_each(i, &modules) { - if (n++ == *pos) - break; - } - if (i == &modules) - return NULL; - return i; + return seq_list_start(&modules, *pos); } static void *m_next(struct seq_file *m, void *p, loff_t *pos) { - struct list_head *i = p; - (*pos)++; - if (i->next == &modules) - return NULL; - return i->next; + return seq_list_next(p, &modules, pos); } static void m_stop(struct seq_file *m, void *p) @@ -2321,25 +2415,24 @@ const struct seq_operations modules_op = { /* Given an address, look for it in the module exception tables. */ const struct exception_table_entry *search_module_extables(unsigned long addr) { - unsigned long flags; const struct exception_table_entry *e = NULL; struct module *mod; - spin_lock_irqsave(&modlist_lock, flags); + preempt_disable(); list_for_each_entry(mod, &modules, list) { if (mod->num_exentries == 0) continue; - + e = search_extable(mod->extable, mod->extable + mod->num_exentries - 1, addr); if (e) break; } - spin_unlock_irqrestore(&modlist_lock, flags); + preempt_enable(); /* Now, if we found one, we are running inside it now, hence - we cannot unload the module, hence no refcnt needed. */ + we cannot unload the module, hence no refcnt needed. */ return e; } @@ -2348,25 +2441,24 @@ const struct exception_table_entry *search_module_extables(unsigned long addr) */ int is_module_address(unsigned long addr) { - unsigned long flags; struct module *mod; - spin_lock_irqsave(&modlist_lock, flags); + preempt_disable(); list_for_each_entry(mod, &modules, list) { if (within(addr, mod->module_core, mod->core_size)) { - spin_unlock_irqrestore(&modlist_lock, flags); + preempt_enable(); return 1; } } - spin_unlock_irqrestore(&modlist_lock, flags); + preempt_enable(); return 0; } -/* Is this a valid kernel address? We don't grab the lock: we are oopsing. */ +/* Is this a valid kernel address? */ struct module *__module_text_address(unsigned long addr) { struct module *mod; @@ -2381,11 +2473,10 @@ struct module *__module_text_address(unsigned long addr) struct module *module_text_address(unsigned long addr) { struct module *mod; - unsigned long flags; - spin_lock_irqsave(&modlist_lock, flags); + preempt_disable(); mod = __module_text_address(addr); - spin_unlock_irqrestore(&modlist_lock, flags); + preempt_enable(); return mod; } @@ -2494,3 +2585,18 @@ EXPORT_SYMBOL(module_remove_driver); void struct_module(struct module *mod) { return; } EXPORT_SYMBOL(struct_module); #endif + +#ifdef CONFIG_MARKERS +void module_update_markers(struct module *probe_module, int *refcount) +{ + struct module *mod; + + mutex_lock(&module_mutex); + list_for_each_entry(mod, &modules, list) + if (!mod->taints) + marker_update_probe_range(mod->markers, + mod->markers + mod->num_markers, + probe_module, refcount); + mutex_unlock(&module_mutex); +} +#endif