This patches switch the order of functions: + lp_enable_func() <-> lp_disable_func() + klp_register_patch() <-> klp_unregister_patch()
It makes it consistent with the rest of the functions. The functions are defined in the order: + klp_disable_*() + klp_enable_*() + klp_free_*() + klp_init_*() + klp_unregister_*() + klp_register_*() The patch also moves the module notification handling after the klp_init*() functions. It will allow to split the common code into __klp_init*() functions and reduce copy&paste stuff. Signed-off-by: Petr Mladek <[email protected]> --- kernel/livepatch/core.c | 282 ++++++++++++++++++++++++------------------------ 1 file changed, 141 insertions(+), 141 deletions(-) diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 54bb39d3abb5..97a8d4a3d6d8 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -280,59 +280,59 @@ static void notrace klp_ftrace_handler(unsigned long ip, regs->ip = (unsigned long)func->new_func; } -static int klp_enable_func(struct klp_func *func) +static int klp_disable_func(struct klp_func *func) { int ret; - if (WARN_ON(!func->old_addr)) + if (WARN_ON(func->state != KLP_ENABLED)) return -EINVAL; - if (WARN_ON(func->state != KLP_DISABLED)) + if (WARN_ON(!func->old_addr)) return -EINVAL; - ret = ftrace_set_filter_ip(func->fops, func->old_addr, 0, 0); + ret = unregister_ftrace_function(func->fops); if (ret) { - pr_err("failed to set ftrace filter for function '%s' (%d)\n", + pr_err("failed to unregister ftrace handler for function '%s' (%d)\n", func->old_name, ret); return ret; } - ret = register_ftrace_function(func->fops); - if (ret) { - pr_err("failed to register ftrace handler for function '%s' (%d)\n", - func->old_name, ret); - ftrace_set_filter_ip(func->fops, func->old_addr, 1, 0); - } else { - func->state = KLP_ENABLED; - } + ret = ftrace_set_filter_ip(func->fops, func->old_addr, 1, 0); + if (ret) + pr_warn("function unregister succeeded but failed to clear the filter\n"); - return ret; + func->state = KLP_DISABLED; + + return 0; } -static int klp_disable_func(struct klp_func *func) +static int klp_enable_func(struct klp_func *func) { int ret; - if (WARN_ON(func->state != KLP_ENABLED)) + if (WARN_ON(!func->old_addr)) return -EINVAL; - if (WARN_ON(!func->old_addr)) + if (WARN_ON(func->state != KLP_DISABLED)) return -EINVAL; - ret = unregister_ftrace_function(func->fops); + ret = ftrace_set_filter_ip(func->fops, func->old_addr, 0, 0); if (ret) { - pr_err("failed to unregister ftrace handler for function '%s' (%d)\n", + pr_err("failed to set ftrace filter for function '%s' (%d)\n", func->old_name, ret); return ret; } - ret = ftrace_set_filter_ip(func->fops, func->old_addr, 1, 0); - if (ret) - pr_warn("function unregister succeeded but failed to clear the filter\n"); - - func->state = KLP_DISABLED; + ret = register_ftrace_function(func->fops); + if (ret) { + pr_err("failed to register ftrace handler for function '%s' (%d)\n", + func->old_name, ret); + ftrace_set_filter_ip(func->fops, func->old_addr, 1, 0); + } else { + func->state = KLP_ENABLED; + } - return 0; + return ret; } static int klp_disable_object(struct klp_object *obj) @@ -504,98 +504,6 @@ err: } EXPORT_SYMBOL_GPL(klp_enable_patch); -static void klp_module_notify_coming(struct module *pmod, - struct klp_object *obj) -{ - struct klp_func *func; - struct module *mod = obj->mod; - int ret; - - pr_notice("applying patch '%s' to loading module '%s'\n", - pmod->name, mod->name); - - if (obj->relocs) { - ret = klp_write_object_relocations(pmod, obj); - if (ret) - goto err; - } - - for (func = obj->funcs; func->old_name; func++) { - ret = klp_find_verify_func_addr(obj, func); - if (ret) - goto err; - } - - ret = klp_enable_object(obj); - if (!ret) - return; - -err: - pr_warn("failed to apply patch '%s' to module '%s' (%d)\n", - pmod->name, mod->name, ret); -} - -static void klp_module_notify_going(struct module *pmod, - struct klp_object *obj) -{ - struct klp_func *func; - struct module *mod = obj->mod; - int ret; - - pr_notice("reverting patch '%s' on unloading module '%s'\n", - pmod->name, mod->name); - - ret = klp_disable_object(obj); - if (ret) - pr_warn("failed to revert patch '%s' on module '%s' (%d)\n", - pmod->name, mod->name, ret); - - for (func = obj->funcs; func->old_name; func++) - func->old_addr = 0; - - obj->mod = NULL; -} - -static int klp_module_notify(struct notifier_block *nb, unsigned long action, - void *data) -{ - struct module *mod = data; - struct klp_patch *patch; - struct klp_object *obj; - - if (action != MODULE_STATE_COMING && action != MODULE_STATE_GOING) - return 0; - - mutex_lock(&klp_mutex); - - list_for_each_entry(patch, &klp_patches, list) { - if (patch->state == KLP_DISABLED) - continue; - - for (obj = patch->objs; obj->funcs; obj++) { - if (!klp_is_module(obj) || strcmp(obj->name, mod->name)) - continue; - - if (action == MODULE_STATE_COMING) { - obj->mod = mod; - klp_module_notify_coming(patch->mod, obj); - } else /* MODULE_STATE_GOING */ - klp_module_notify_going(patch->mod, obj); - - break; - } - } - - mutex_unlock(&klp_mutex); - - return 0; -} - -static struct notifier_block klp_module_nb = { - .notifier_call = klp_module_notify, - .priority = INT_MIN+1, /* called late but before ftrace notifier */ -}; - /* * Sysfs Interface * @@ -823,6 +731,41 @@ unlock: } /** + * klp_unregister_patch() - unregisters a patch + * @patch: Disabled patch to be unregistered + * + * Frees the data structures and removes the sysfs interface. + * + * Return: 0 on success, otherwise error + */ +int klp_unregister_patch(struct klp_patch *patch) +{ + int ret = 0; + + if (!klp_is_enabled()) + return -ENODEV; + + mutex_lock(&klp_mutex); + + if (!klp_patch_is_registered(patch)) { + ret = -EINVAL; + goto out; + } + + if (patch->state == KLP_ENABLED) { + ret = -EBUSY; + goto out; + } + + klp_free_patch(patch); + +out: + mutex_unlock(&klp_mutex); + return ret; +} +EXPORT_SYMBOL_GPL(klp_unregister_patch); + +/** * klp_register_patch() - registers a patch * @patch: Patch to be registered * @@ -859,40 +802,97 @@ int klp_register_patch(struct klp_patch *patch) } EXPORT_SYMBOL_GPL(klp_register_patch); -/** - * klp_unregister_patch() - unregisters a patch - * @patch: Disabled patch to be unregistered - * - * Frees the data structures and removes the sysfs interface. - * - * Return: 0 on success, otherwise error - */ -int klp_unregister_patch(struct klp_patch *patch) +static void klp_module_notify_coming(struct module *pmod, + struct klp_object *obj) { - int ret = 0; - - if (!klp_is_enabled()) - return -ENODEV; + struct klp_func *func; + struct module *mod = obj->mod; + int ret; - mutex_lock(&klp_mutex); + pr_notice("applying patch '%s' to loading module '%s'\n", + pmod->name, mod->name); - if (!klp_patch_is_registered(patch)) { - ret = -EINVAL; - goto out; + if (obj->relocs) { + ret = klp_write_object_relocations(pmod, obj); + if (ret) + goto err; } - if (patch->state == KLP_ENABLED) { - ret = -EBUSY; - goto out; + for (func = obj->funcs; func->old_name; func++) { + ret = klp_find_verify_func_addr(obj, func); + if (ret) + goto err; } - klp_free_patch(patch); + ret = klp_enable_object(obj); + if (!ret) + return; + +err: + pr_warn("failed to apply patch '%s' to module '%s' (%d)\n", + pmod->name, mod->name, ret); +} + +static void klp_module_notify_going(struct module *pmod, + struct klp_object *obj) +{ + struct klp_func *func; + struct module *mod = obj->mod; + int ret; + + pr_notice("reverting patch '%s' on unloading module '%s'\n", + pmod->name, mod->name); + + ret = klp_disable_object(obj); + if (ret) + pr_warn("failed to revert patch '%s' on module '%s' (%d)\n", + pmod->name, mod->name, ret); + + for (func = obj->funcs; func->old_name; func++) + func->old_addr = 0; + + obj->mod = NULL; +} + +static int klp_module_notify(struct notifier_block *nb, unsigned long action, + void *data) +{ + struct module *mod = data; + struct klp_patch *patch; + struct klp_object *obj; + + if (action != MODULE_STATE_COMING && action != MODULE_STATE_GOING) + return 0; + + mutex_lock(&klp_mutex); + + list_for_each_entry(patch, &klp_patches, list) { + if (patch->state == KLP_DISABLED) + continue; + + for (obj = patch->objs; obj->funcs; obj++) { + if (!klp_is_module(obj) || strcmp(obj->name, mod->name)) + continue; + + if (action == MODULE_STATE_COMING) { + obj->mod = mod; + klp_module_notify_coming(patch->mod, obj); + } else /* MODULE_STATE_GOING */ + klp_module_notify_going(patch->mod, obj); + + break; + } + } -out: mutex_unlock(&klp_mutex); - return ret; + + return 0; } -EXPORT_SYMBOL_GPL(klp_unregister_patch); + +static struct notifier_block klp_module_nb = { + .notifier_call = klp_module_notify, + .priority = INT_MIN+1, /* called late but before ftrace notifier */ +}; static int klp_init(void) { -- 1.8.5.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
