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 <pmladek@xxxxxxx>
---
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
--
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