diff options
| -rw-r--r-- | include/linux/kmod.h | 2 | ||||
| -rw-r--r-- | kernel/kmod.c | 120 | ||||
| -rw-r--r-- | kernel/module.c | 26 | ||||
| -rw-r--r-- | kernel/params.c | 1 |
4 files changed, 139 insertions, 10 deletions
diff --git a/include/linux/kmod.h b/include/linux/kmod.h index 10f505c..cc8e674 100644 --- a/include/linux/kmod.h +++ b/include/linux/kmod.h @@ -28,8 +28,10 @@ #ifdef CONFIG_KMOD /* modprobe exit status on success, -ve on error. Return value * usually useless though. */ +extern void kmod_sysfs_init(void); extern int request_module(const char * name, ...) __attribute__ ((format (printf, 1, 2))); #else +static inline void kmod_sysfs_init(void) {}; static inline int request_module(const char * name, ...) { return -ENOSYS; } #endif diff --git a/kernel/kmod.c b/kernel/kmod.c index 7962761..9f923f8 100644 --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -36,6 +36,8 @@ #include <linux/resource.h> #include <asm/uaccess.h> +extern int delete_module(const char *name, unsigned int flags); + extern int max_threads; static struct workqueue_struct *khelper_wq; @@ -46,6 +48,7 @@ static struct workqueue_struct *khelper_wq; modprobe_path is set via /proc/sys. */ char modprobe_path[KMOD_PATH_LEN] = "/sbin/modprobe"; +struct module_kobject kmod_mk; /** * request_module - try to load a kernel module @@ -75,6 +78,11 @@ int request_module(const char *fmt, ...) static atomic_t kmod_concurrent = ATOMIC_INIT(0); #define MAX_KMOD_CONCURRENT 50 /* Completely arbitrary value - KAO */ static int kmod_loop_msg; + char modalias[16 + MODULE_NAME_LEN] = "MODALIAS="; + char *uevent_envp[2] = { + modalias, + NULL + }; va_start(args, fmt); ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args); @@ -82,6 +90,12 @@ int request_module(const char *fmt, ...) if (ret >= MODULE_NAME_LEN) return -ENAMETOOLONG; + strcpy(&modalias[strlen("MODALIAS=")], module_name); + kobject_uevent_env(&kmod_mk.kobj, KOBJ_CHANGE, uevent_envp); + + if (modprobe_path[0] == '\0') + goto out; + /* If modprobe needs a service that is in a module, we get a recursive * loop. Limit the number of running kmod threads to max_threads/2 or * MAX_KMOD_CONCURRENT, whichever is the smaller. A cleaner method @@ -108,9 +122,115 @@ int request_module(const char *fmt, ...) ret = call_usermodehelper(modprobe_path, argv, envp, 1); atomic_dec(&kmod_concurrent); +out: return ret; } EXPORT_SYMBOL(request_module); + +static ssize_t store_mod_request(struct module_attribute *mattr, + struct module *mod, + const char *buffer, size_t count) +{ + char name[MODULE_NAME_LEN]; + int ret; + + if (count < 1 || count+1 > MODULE_NAME_LEN) + return -EINVAL; + memcpy(name, buffer, count); + name[count] = '\0'; + if (name[count-1] == '\n') + name[count-1] = '\0'; + + ret = request_module(name); + if (ret < 0) + return ret; + return count; +} + +static struct module_attribute mod_request = { + .attr = { .name = "mod_request", .mode = S_IWUSR, .owner = THIS_MODULE }, + .store = store_mod_request, +}; + +#ifdef CONFIG_MODULE_UNLOAD +static ssize_t store_mod_unload(struct module_attribute *mattr, + struct module *mod, + const char *buffer, size_t count) +{ + char name[MODULE_NAME_LEN]; + int ret; + + if (count < 1 || count+1 > MODULE_NAME_LEN) + return -EINVAL; + memcpy(name, buffer, count); + name[count] = '\0'; + if (name[count-1] == '\n') + name[count-1] = '\0'; + + ret = delete_module(name, O_NONBLOCK); + if (ret < 0) + return ret; + return count; +} + +static struct module_attribute mod_unload = { + .attr = { .name = "mod_unload", .mode = S_IWUSR, .owner = THIS_MODULE }, + .store = store_mod_unload, +}; +#endif + +static ssize_t show_mod_request_helper(struct module_attribute *mattr, + struct module *mod, + char *buffer) +{ + return sprintf(buffer, "%s\n", modprobe_path); +} + +static ssize_t store_mod_request_helper(struct module_attribute *mattr, + struct module *mod, + const char *buffer, size_t count) +{ + if (count < 1 || count+1 > KMOD_PATH_LEN) + return -EINVAL; + memcpy(modprobe_path, buffer, count); + modprobe_path[count] = '\0'; + if (modprobe_path[count-1] == '\n') + modprobe_path[count-1] = '\0'; + return count; +} + +static struct module_attribute mod_request_helper = { + .attr = { + .name = "mod_request_helper", + .mode = S_IWUSR | S_IRUGO, + .owner = THIS_MODULE + }, + .show = show_mod_request_helper, + .store = store_mod_request_helper, +}; + +void __init kmod_sysfs_init(void) +{ + int ret; + + kmod_mk.mod = THIS_MODULE; + kobj_set_kset_s(&kmod_mk, module_subsys); + kobject_set_name(&kmod_mk.kobj, "kmod"); + kobject_init(&kmod_mk.kobj); + ret = kobject_add(&kmod_mk.kobj); + if (ret < 0) + goto out; + + ret = sysfs_create_file(&kmod_mk.kobj, &mod_request_helper.attr); + ret = sysfs_create_file(&kmod_mk.kobj, &mod_request.attr); +#ifdef CONFIG_MODULE_UNLOAD + ret = sysfs_create_file(&kmod_mk.kobj, &mod_unload.attr); +#endif + + kobject_uevent(&kmod_mk.kobj, KOBJ_ADD); +out: + return; +} #endif /* CONFIG_KMOD */ struct subprocess_info { diff --git a/kernel/module.c b/kernel/module.c index 8a94e05..225501f 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -653,20 +653,11 @@ static void wait_for_zero_refcount(struct module *mod) mutex_lock(&module_mutex); } -asmlinkage long -sys_delete_module(const char __user *name_user, unsigned int flags) +int delete_module(const char *name, unsigned int flags) { struct module *mod; - char name[MODULE_NAME_LEN]; int ret, forced = 0; - if (!capable(CAP_SYS_MODULE)) - return -EPERM; - - if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) - return -EFAULT; - name[MODULE_NAME_LEN-1] = '\0'; - if (mutex_lock_interruptible(&module_mutex) != 0) return -EINTR; @@ -727,6 +718,21 @@ sys_delete_module(const char __user *name_user, unsigned int flags) return ret; } +asmlinkage long +sys_delete_module(const char __user *name_user, unsigned int flags) +{ + char name[MODULE_NAME_LEN]; + + if (!capable(CAP_SYS_MODULE)) + return -EPERM; + + if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) + return -EFAULT; + name[MODULE_NAME_LEN-1] = '\0'; + + return delete_module(name, flags); +} + static void print_unload_info(struct seq_file *m, struct module *mod) { struct module_use *use; diff --git a/kernel/params.c b/kernel/params.c index 553cf7d..7d231c6 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -714,6 +714,7 @@ static int __init param_sysfs_init(void) } param_sysfs_builtin(); + kmod_sysfs_init(); return 0; } |
