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-rw-r--r--kernel/livepatch/core.c78
1 files changed, 48 insertions, 30 deletions
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index 9ec555732f1a..c40ebcca0495 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -128,7 +128,7 @@ static bool klp_is_patch_registered(struct klp_patch *patch)
static bool klp_initialized(void)
{
- return klp_root_kobj;
+ return !!klp_root_kobj;
}
struct klp_find_arg {
@@ -242,8 +242,9 @@ static int klp_find_verify_func_addr(struct klp_object *obj,
int ret;
#if defined(CONFIG_RANDOMIZE_BASE)
- /* KASLR is enabled, disregard old_addr from user */
- func->old_addr = 0;
+ /* If KASLR has been enabled, adjust old_addr accordingly */
+ if (kaslr_enabled() && func->old_addr)
+ func->old_addr += kaslr_offset();
#endif
if (!func->old_addr || klp_is_module(obj))
@@ -430,7 +431,7 @@ static void klp_disable_object(struct klp_object *obj)
{
struct klp_func *func;
- for (func = obj->funcs; func->old_name; func++)
+ klp_for_each_func(obj, func)
if (func->state == KLP_ENABLED)
klp_disable_func(func);
@@ -448,7 +449,7 @@ static int klp_enable_object(struct klp_object *obj)
if (WARN_ON(!klp_is_object_loaded(obj)))
return -EINVAL;
- for (func = obj->funcs; func->old_name; func++) {
+ klp_for_each_func(obj, func) {
ret = klp_enable_func(func);
if (ret) {
klp_disable_object(obj);
@@ -471,7 +472,7 @@ static int __klp_disable_patch(struct klp_patch *patch)
pr_notice("disabling patch '%s'\n", patch->mod->name);
- for (obj = patch->objs; obj->funcs; obj++) {
+ klp_for_each_object(patch, obj) {
if (obj->state == KLP_ENABLED)
klp_disable_object(obj);
}
@@ -531,7 +532,7 @@ static int __klp_enable_patch(struct klp_patch *patch)
pr_notice("enabling patch '%s'\n", patch->mod->name);
- for (obj = patch->objs; obj->funcs; obj++) {
+ klp_for_each_object(patch, obj) {
if (!klp_is_object_loaded(obj))
continue;
@@ -659,6 +660,15 @@ static struct kobj_type klp_ktype_patch = {
.default_attrs = klp_patch_attrs,
};
+static void klp_kobj_release_object(struct kobject *kobj)
+{
+}
+
+static struct kobj_type klp_ktype_object = {
+ .release = klp_kobj_release_object,
+ .sysfs_ops = &kobj_sysfs_ops,
+};
+
static void klp_kobj_release_func(struct kobject *kobj)
{
}
@@ -688,7 +698,7 @@ static void klp_free_object_loaded(struct klp_object *obj)
obj->mod = NULL;
- for (func = obj->funcs; func->old_name; func++)
+ klp_for_each_func(obj, func)
func->old_addr = 0;
}
@@ -703,7 +713,7 @@ static void klp_free_objects_limited(struct klp_patch *patch,
for (obj = patch->objs; obj->funcs && obj != limit; obj++) {
klp_free_funcs_limited(obj, NULL);
- kobject_put(obj->kobj);
+ kobject_put(&obj->kobj);
}
}
@@ -721,7 +731,7 @@ static int klp_init_func(struct klp_object *obj, struct klp_func *func)
func->state = KLP_DISABLED;
return kobject_init_and_add(&func->kobj, &klp_ktype_func,
- obj->kobj, "%s", func->old_name);
+ &obj->kobj, "%s", func->old_name);
}
/* parts of the initialization that is done only when the object is loaded */
@@ -737,7 +747,7 @@ static int klp_init_object_loaded(struct klp_patch *patch,
return ret;
}
- for (func = obj->funcs; func->old_name; func++) {
+ klp_for_each_func(obj, func) {
ret = klp_find_verify_func_addr(obj, func);
if (ret)
return ret;
@@ -761,11 +771,12 @@ static int klp_init_object(struct klp_patch *patch, struct klp_object *obj)
klp_find_object_module(obj);
name = klp_is_module(obj) ? obj->name : "vmlinux";
- obj->kobj = kobject_create_and_add(name, &patch->kobj);
- if (!obj->kobj)
- return -ENOMEM;
+ ret = kobject_init_and_add(&obj->kobj, &klp_ktype_object,
+ &patch->kobj, "%s", name);
+ if (ret)
+ return ret;
- for (func = obj->funcs; func->old_name; func++) {
+ klp_for_each_func(obj, func) {
ret = klp_init_func(obj, func);
if (ret)
goto free;
@@ -781,7 +792,7 @@ static int klp_init_object(struct klp_patch *patch, struct klp_object *obj)
free:
klp_free_funcs_limited(obj, func);
- kobject_put(obj->kobj);
+ kobject_put(&obj->kobj);
return ret;
}
@@ -802,7 +813,7 @@ static int klp_init_patch(struct klp_patch *patch)
if (ret)
goto unlock;
- for (obj = patch->objs; obj->funcs; obj++) {
+ klp_for_each_object(patch, obj) {
ret = klp_init_object(patch, obj);
if (ret)
goto free;
@@ -891,7 +902,7 @@ int klp_register_patch(struct klp_patch *patch)
}
EXPORT_SYMBOL_GPL(klp_register_patch);
-static void klp_module_notify_coming(struct klp_patch *patch,
+static int klp_module_notify_coming(struct klp_patch *patch,
struct klp_object *obj)
{
struct module *pmod = patch->mod;
@@ -899,22 +910,23 @@ static void klp_module_notify_coming(struct klp_patch *patch,
int ret;
ret = klp_init_object_loaded(patch, obj);
- if (ret)
- goto err;
+ if (ret) {
+ pr_warn("failed to initialize patch '%s' for module '%s' (%d)\n",
+ pmod->name, mod->name, ret);
+ return ret;
+ }
if (patch->state == KLP_DISABLED)
- return;
+ return 0;
pr_notice("applying patch '%s' to loading module '%s'\n",
pmod->name, mod->name);
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);
+ if (ret)
+ pr_warn("failed to apply patch '%s' to module '%s' (%d)\n",
+ pmod->name, mod->name, ret);
+ return ret;
}
static void klp_module_notify_going(struct klp_patch *patch,
@@ -938,6 +950,7 @@ disabled:
static int klp_module_notify(struct notifier_block *nb, unsigned long action,
void *data)
{
+ int ret;
struct module *mod = data;
struct klp_patch *patch;
struct klp_object *obj;
@@ -957,13 +970,18 @@ static int klp_module_notify(struct notifier_block *nb, unsigned long action,
mod->klp_alive = false;
list_for_each_entry(patch, &klp_patches, list) {
- for (obj = patch->objs; obj->funcs; obj++) {
+ klp_for_each_object(patch, 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, obj);
+ ret = klp_module_notify_coming(patch, obj);
+ if (ret) {
+ obj->mod = NULL;
+ pr_warn("patch '%s' is in an inconsistent state!\n",
+ patch->mod->name);
+ }
} else /* MODULE_STATE_GOING */
klp_module_notify_going(patch, obj);
@@ -981,7 +999,7 @@ static struct notifier_block klp_module_nb = {
.priority = INT_MIN+1, /* called late but before ftrace notifier */
};
-static int klp_init(void)
+static int __init klp_init(void)
{
int ret;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-24 18:40:11 +0100