diff options
| -rw-r--r-- | include/linux/module.h | 22 | ||||
| -rw-r--r-- | kernel/extable.c | 3 | ||||
| -rw-r--r-- | kernel/kallsyms.c | 11 | ||||
| -rw-r--r-- | kernel/module.c | 102 | ||||
| -rw-r--r-- | kernel/params.c | 8 |
5 files changed, 90 insertions, 56 deletions
diff --git a/include/linux/module.h b/include/linux/module.h index c97bdb7eb957..aedc06be1de8 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -446,11 +446,14 @@ static inline void __module_get(struct module *module) __mod ? __mod->name : "kernel"; \ }) -/* For kallsyms to ask for address resolution. NULL means not found. */ -const char *module_address_lookup(unsigned long addr, - unsigned long *symbolsize, - unsigned long *offset, - char **modname); +/* For kallsyms to ask for address resolution. namebuf should be at + * least KSYM_NAME_LEN long: a pointer to namebuf is returned if + * found, otherwise NULL. */ +char *module_address_lookup(unsigned long addr, + unsigned long *symbolsize, + unsigned long *offset, + char **modname, + char *namebuf); int lookup_module_symbol_name(unsigned long addr, char *symname); int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name); @@ -516,10 +519,11 @@ static inline void module_put(struct module *module) #define module_name(mod) "kernel" /* For kallsyms to ask for address resolution. NULL means not found. */ -static inline const char *module_address_lookup(unsigned long addr, - unsigned long *symbolsize, - unsigned long *offset, - char **modname) +static inline char *module_address_lookup(unsigned long addr, + unsigned long *symbolsize, + unsigned long *offset, + char **modname, + char *namebuf) { return NULL; } diff --git a/kernel/extable.c b/kernel/extable.c index 7fe262855317..a26cb2e17023 100644 --- a/kernel/extable.c +++ b/kernel/extable.c @@ -46,7 +46,8 @@ int core_kernel_text(unsigned long addr) addr <= (unsigned long)_etext) return 1; - if (addr >= (unsigned long)_sinittext && + if (system_state == SYSTEM_BOOTING && + addr >= (unsigned long)_sinittext && addr <= (unsigned long)_einittext) return 1; return 0; diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 2fc25810509e..7dadc71ce516 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -233,10 +233,11 @@ static unsigned long get_symbol_pos(unsigned long addr, int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize, unsigned long *offset) { + char namebuf[KSYM_NAME_LEN]; if (is_ksym_addr(addr)) return !!get_symbol_pos(addr, symbolsize, offset); - return !!module_address_lookup(addr, symbolsize, offset, NULL); + return !!module_address_lookup(addr, symbolsize, offset, NULL, namebuf); } /* @@ -251,8 +252,6 @@ const char *kallsyms_lookup(unsigned long addr, unsigned long *offset, char **modname, char *namebuf) { - const char *msym; - namebuf[KSYM_NAME_LEN - 1] = 0; namebuf[0] = 0; @@ -268,10 +267,8 @@ const char *kallsyms_lookup(unsigned long addr, } /* see if it's in a module */ - msym = module_address_lookup(addr, symbolsize, offset, modname); - if (msym) - return strncpy(namebuf, msym, KSYM_NAME_LEN - 1); - + return module_address_lookup(addr, symbolsize, offset, modname, + namebuf); return NULL; } diff --git a/kernel/module.c b/kernel/module.c index 1bb4c5e0d56e..f6a4e721fd49 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -65,6 +65,9 @@ static DEFINE_MUTEX(module_mutex); static LIST_HEAD(modules); +/* Waiting for a module to finish initializing? */ +static DECLARE_WAIT_QUEUE_HEAD(module_wq); + static BLOCKING_NOTIFIER_HEAD(module_notify_list); int register_module_notifier(struct notifier_block * nb) @@ -84,8 +87,11 @@ EXPORT_SYMBOL(unregister_module_notifier); static inline int strong_try_module_get(struct module *mod) { if (mod && mod->state == MODULE_STATE_COMING) + return -EBUSY; + if (try_module_get(mod)) return 0; - return try_module_get(mod); + else + return -ENOENT; } static inline void add_taint_module(struct module *mod, unsigned flag) @@ -539,11 +545,21 @@ static int already_uses(struct module *a, struct module *b) static int use_module(struct module *a, struct module *b) { struct module_use *use; - int no_warn; + int no_warn, err; if (b == NULL || already_uses(a, b)) return 1; - if (!strong_try_module_get(b)) + /* If we're interrupted or time out, we fail. */ + if (wait_event_interruptible_timeout( + module_wq, (err = strong_try_module_get(b)) != -EBUSY, + 30 * HZ) <= 0) { + printk("%s: gave up waiting for init of module %s.\n", + a->name, b->name); + return 0; + } + + /* If strong_try_module_get() returned a different error, we fail. */ + if (err) return 0; DEBUGP("Allocating new usage for %s.\n", a->name); @@ -722,7 +738,7 @@ sys_delete_module(const char __user *name_user, unsigned int flags) mutex_lock(&module_mutex); } /* Store the name of the last unloaded module for diagnostic purposes */ - sprintf(last_unloaded_module, mod->name); + strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); free_module(mod); out: @@ -816,7 +832,7 @@ static inline void module_unload_free(struct module *mod) static inline int use_module(struct module *a, struct module *b) { - return strong_try_module_get(b); + return strong_try_module_get(b) == 0; } static inline void module_unload_init(struct module *mod) @@ -1214,6 +1230,7 @@ void module_remove_modinfo_attrs(struct module *mod) int mod_sysfs_init(struct module *mod) { int err; + struct kobject *kobj; if (!module_sysfs_initialized) { printk(KERN_ERR "%s: module sysfs not initialized\n", @@ -1221,6 +1238,15 @@ int mod_sysfs_init(struct module *mod) err = -EINVAL; goto out; } + + kobj = kset_find_obj(module_kset, mod->name); + if (kobj) { + printk(KERN_ERR "%s: module is already loaded\n", mod->name); + kobject_put(kobj); + err = -EINVAL; + goto out; + } + mod->mkobj.mod = mod; memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); @@ -1278,6 +1304,17 @@ static void mod_kobject_remove(struct module *mod) } /* + * link the module with the whole machine is stopped with interrupts off + * - this defends against kallsyms not taking locks + */ +static int __link_module(void *_mod) +{ + struct module *mod = _mod; + list_add(&mod->list, &modules); + return 0; +} + +/* * unlink the module with the whole machine is stopped with interrupts off * - this defends against kallsyms not taking locks */ @@ -1326,7 +1363,7 @@ void *__symbol_get(const char *symbol) preempt_disable(); value = __find_symbol(symbol, &owner, &crc, 1); - if (value && !strong_try_module_get(owner)) + if (value && strong_try_module_get(owner) != 0) value = 0; preempt_enable(); @@ -1889,7 +1926,7 @@ static struct module *load_module(void __user *umod, set_license(mod, get_modinfo(sechdrs, infoindex, "license")); if (strcmp(mod->name, "ndiswrapper") == 0) - add_taint(TAINT_PROPRIETARY_MODULE); + add_taint_module(mod, TAINT_PROPRIETARY_MODULE); if (strcmp(mod->name, "driverloader") == 0) add_taint_module(mod, TAINT_PROPRIETARY_MODULE); @@ -2019,6 +2056,11 @@ static struct module *load_module(void __user *umod, printk(KERN_WARNING "%s: Ignoring obsolete parameters\n", mod->name); + /* Now sew it into the lists so we can get lockdep and oops + * info during argument parsing. Noone should access us, since + * strong_try_module_get() will fail. */ + stop_machine_run(__link_module, mod, NR_CPUS); + /* Size of section 0 is 0, so this works well if no params */ err = parse_args(mod->name, mod->args, (struct kernel_param *) @@ -2027,7 +2069,7 @@ static struct module *load_module(void __user *umod, / sizeof(struct kernel_param), NULL); if (err < 0) - goto arch_cleanup; + goto unlink; err = mod_sysfs_setup(mod, (struct kernel_param *) @@ -2035,7 +2077,7 @@ static struct module *load_module(void __user *umod, sechdrs[setupindex].sh_size / sizeof(struct kernel_param)); if (err < 0) - goto arch_cleanup; + goto unlink; add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs); add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs); @@ -2050,7 +2092,8 @@ static struct module *load_module(void __user *umod, /* Done! */ return mod; - arch_cleanup: + unlink: + stop_machine_run(__unlink_module, mod, NR_CPUS); module_arch_cleanup(mod); cleanup: kobject_del(&mod->mkobj.kobj); @@ -2075,17 +2118,6 @@ static struct module *load_module(void __user *umod, goto free_hdr; } -/* - * link the module with the whole machine is stopped with interrupts off - * - this defends against kallsyms not taking locks - */ -static int __link_module(void *_mod) -{ - struct module *mod = _mod; - list_add(&mod->list, &modules); - return 0; -} - /* This is where the real work happens */ asmlinkage long sys_init_module(void __user *umod, @@ -2110,10 +2142,6 @@ sys_init_module(void __user *umod, return PTR_ERR(mod); } - /* Now sew it into the lists. They won't access us, since - strong_try_module_get() will fail. */ - stop_machine_run(__link_module, mod, NR_CPUS); - /* Drop lock so they can recurse */ mutex_unlock(&module_mutex); @@ -2132,6 +2160,7 @@ sys_init_module(void __user *umod, mutex_lock(&module_mutex); free_module(mod); mutex_unlock(&module_mutex); + wake_up(&module_wq); return ret; } @@ -2146,6 +2175,7 @@ sys_init_module(void __user *umod, mod->init_size = 0; mod->init_text_size = 0; mutex_unlock(&module_mutex); + wake_up(&module_wq); return 0; } @@ -2210,14 +2240,13 @@ static const char *get_ksymbol(struct module *mod, return mod->strtab + mod->symtab[best].st_name; } -/* For kallsyms to ask for address resolution. NULL means not found. - We don't lock, as this is used for oops resolution and races are a - lesser concern. */ -/* FIXME: Risky: returns a pointer into a module w/o lock */ -const char *module_address_lookup(unsigned long addr, - unsigned long *size, - unsigned long *offset, - char **modname) +/* For kallsyms to ask for address resolution. NULL means not found. Careful + * not to lock to avoid deadlock on oopses, simply disable preemption. */ +char *module_address_lookup(unsigned long addr, + unsigned long *size, + unsigned long *offset, + char **modname, + char *namebuf) { struct module *mod; const char *ret = NULL; @@ -2232,8 +2261,13 @@ const char *module_address_lookup(unsigned long addr, break; } } + /* Make a copy in here where it's safe */ + if (ret) { + strncpy(namebuf, ret, KSYM_NAME_LEN - 1); + ret = namebuf; + } preempt_enable(); - return ret; + return (char *)ret; } int lookup_module_symbol_name(unsigned long addr, char *symname) diff --git a/kernel/params.c b/kernel/params.c index 67f65ee7211d..42fe5e6126c0 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -376,8 +376,6 @@ int param_get_string(char *buffer, struct kernel_param *kp) extern struct kernel_param __start___param[], __stop___param[]; -#define MAX_KBUILD_MODNAME KOBJ_NAME_LEN - struct param_attribute { struct module_attribute mattr; @@ -587,7 +585,7 @@ static void __init param_sysfs_builtin(void) { struct kernel_param *kp, *kp_begin = NULL; unsigned int i, name_len, count = 0; - char modname[MAX_KBUILD_MODNAME + 1] = ""; + char modname[MODULE_NAME_LEN + 1] = ""; for (i=0; i < __stop___param - __start___param; i++) { char *dot; @@ -595,12 +593,12 @@ static void __init param_sysfs_builtin(void) kp = &__start___param[i]; max_name_len = - min_t(size_t, MAX_KBUILD_MODNAME, strlen(kp->name)); + min_t(size_t, MODULE_NAME_LEN, strlen(kp->name)); dot = memchr(kp->name, '.', max_name_len); if (!dot) { DEBUGP("couldn't find period in first %d characters " - "of %s\n", MAX_KBUILD_MODNAME, kp->name); + "of %s\n", MODULE_NAME_LEN, kp->name); continue; } name_len = dot - kp->name; |