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Diffstat (limited to 'kernel/livepatch')
-rw-r--r--kernel/livepatch/core.c91
-rw-r--r--kernel/livepatch/transition.c22
2 files changed, 48 insertions, 65 deletions
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index 34a8338657d2..f6fbaff10e71 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -427,7 +427,13 @@ static void klp_free_object_dynamic(struct klp_object *obj)
kfree(obj);
}
-static struct klp_object *klp_alloc_object_dynamic(const char *name)
+static void klp_init_func_early(struct klp_object *obj,
+ struct klp_func *func);
+static void klp_init_object_early(struct klp_patch *patch,
+ struct klp_object *obj);
+
+static struct klp_object *klp_alloc_object_dynamic(const char *name,
+ struct klp_patch *patch)
{
struct klp_object *obj;
@@ -443,7 +449,7 @@ static struct klp_object *klp_alloc_object_dynamic(const char *name)
}
}
- INIT_LIST_HEAD(&obj->func_list);
+ klp_init_object_early(patch, obj);
obj->dynamic = true;
return obj;
@@ -472,6 +478,7 @@ static struct klp_func *klp_alloc_func_nop(struct klp_func *old_func,
}
}
+ klp_init_func_early(obj, func);
/*
* func->new_func is same as func->old_func. These addresses are
* set when the object is loaded, see klp_init_object_loaded().
@@ -491,11 +498,9 @@ static int klp_add_object_nops(struct klp_patch *patch,
obj = klp_find_object(patch, old_obj);
if (!obj) {
- obj = klp_alloc_object_dynamic(old_obj->name);
+ obj = klp_alloc_object_dynamic(old_obj->name, patch);
if (!obj)
return -ENOMEM;
-
- list_add_tail(&obj->node, &patch->obj_list);
}
klp_for_each_func(old_obj, old_func) {
@@ -506,8 +511,6 @@ static int klp_add_object_nops(struct klp_patch *patch,
func = klp_alloc_func_nop(old_func, obj);
if (!func)
return -ENOMEM;
-
- list_add_tail(&func->node, &obj->func_list);
}
return 0;
@@ -589,13 +592,7 @@ static void __klp_free_funcs(struct klp_object *obj, bool nops_only)
continue;
list_del(&func->node);
-
- /* Might be called from klp_init_patch() error path. */
- if (func->kobj_added) {
- kobject_put(&func->kobj);
- } else if (func->nop) {
- klp_free_func_nop(func);
- }
+ kobject_put(&func->kobj);
}
}
@@ -625,13 +622,7 @@ static void __klp_free_objects(struct klp_patch *patch, bool nops_only)
continue;
list_del(&obj->node);
-
- /* Might be called from klp_init_patch() error path. */
- if (obj->kobj_added) {
- kobject_put(&obj->kobj);
- } else if (obj->dynamic) {
- klp_free_object_dynamic(obj);
- }
+ kobject_put(&obj->kobj);
}
}
@@ -676,10 +667,8 @@ static void klp_free_patch_finish(struct klp_patch *patch)
* this is called when the patch gets disabled and it
* cannot get enabled again.
*/
- if (patch->kobj_added) {
- kobject_put(&patch->kobj);
- wait_for_completion(&patch->finish);
- }
+ kobject_put(&patch->kobj);
+ wait_for_completion(&patch->finish);
/* Put the module after the last access to struct klp_patch. */
if (!patch->forced)
@@ -701,8 +690,6 @@ static void klp_free_patch_work_fn(struct work_struct *work)
static int klp_init_func(struct klp_object *obj, struct klp_func *func)
{
- int ret;
-
if (!func->old_name)
return -EINVAL;
@@ -725,13 +712,9 @@ static int klp_init_func(struct klp_object *obj, struct klp_func *func)
* object. If the user selects 0 for old_sympos, then 1 will be used
* since a unique symbol will be the first occurrence.
*/
- ret = kobject_init_and_add(&func->kobj, &klp_ktype_func,
- &obj->kobj, "%s,%lu", func->old_name,
- func->old_sympos ? func->old_sympos : 1);
- if (!ret)
- func->kobj_added = true;
-
- return ret;
+ return kobject_add(&func->kobj, &obj->kobj, "%s,%lu",
+ func->old_name,
+ func->old_sympos ? func->old_sympos : 1);
}
/* Arches may override this to finish any remaining arch-specific tasks */
@@ -802,11 +785,9 @@ 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";
- ret = kobject_init_and_add(&obj->kobj, &klp_ktype_object,
- &patch->kobj, "%s", name);
+ ret = kobject_add(&obj->kobj, &patch->kobj, "%s", name);
if (ret)
return ret;
- obj->kobj_added = true;
klp_for_each_func(obj, func) {
ret = klp_init_func(obj, func);
@@ -820,6 +801,21 @@ static int klp_init_object(struct klp_patch *patch, struct klp_object *obj)
return ret;
}
+static void klp_init_func_early(struct klp_object *obj,
+ struct klp_func *func)
+{
+ kobject_init(&func->kobj, &klp_ktype_func);
+ list_add_tail(&func->node, &obj->func_list);
+}
+
+static void klp_init_object_early(struct klp_patch *patch,
+ struct klp_object *obj)
+{
+ INIT_LIST_HEAD(&obj->func_list);
+ kobject_init(&obj->kobj, &klp_ktype_object);
+ list_add_tail(&obj->node, &patch->obj_list);
+}
+
static int klp_init_patch_early(struct klp_patch *patch)
{
struct klp_object *obj;
@@ -830,7 +826,7 @@ static int klp_init_patch_early(struct klp_patch *patch)
INIT_LIST_HEAD(&patch->list);
INIT_LIST_HEAD(&patch->obj_list);
- patch->kobj_added = false;
+ kobject_init(&patch->kobj, &klp_ktype_patch);
patch->enabled = false;
patch->forced = false;
INIT_WORK(&patch->free_work, klp_free_patch_work_fn);
@@ -840,13 +836,10 @@ static int klp_init_patch_early(struct klp_patch *patch)
if (!obj->funcs)
return -EINVAL;
- INIT_LIST_HEAD(&obj->func_list);
- obj->kobj_added = false;
- list_add_tail(&obj->node, &patch->obj_list);
+ klp_init_object_early(patch, obj);
klp_for_each_func_static(obj, func) {
- func->kobj_added = false;
- list_add_tail(&func->node, &obj->func_list);
+ klp_init_func_early(obj, func);
}
}
@@ -861,11 +854,9 @@ static int klp_init_patch(struct klp_patch *patch)
struct klp_object *obj;
int ret;
- ret = kobject_init_and_add(&patch->kobj, &klp_ktype_patch,
- klp_root_kobj, "%s", patch->mod->name);
+ ret = kobject_add(&patch->kobj, klp_root_kobj, "%s", patch->mod->name);
if (ret)
return ret;
- patch->kobj_added = true;
if (patch->replace) {
ret = klp_add_nops(patch);
@@ -927,9 +918,6 @@ static int __klp_enable_patch(struct klp_patch *patch)
if (WARN_ON(patch->enabled))
return -EINVAL;
- if (!patch->kobj_added)
- return -EINVAL;
-
pr_notice("enabling patch '%s'\n", patch->mod->name);
klp_init_transition(patch, KLP_PATCHED);
@@ -1004,11 +992,10 @@ int klp_enable_patch(struct klp_patch *patch)
return -ENODEV;
if (!klp_have_reliable_stack()) {
- pr_err("This architecture doesn't have support for the livepatch consistency model.\n");
- return -EOPNOTSUPP;
+ pr_warn("This architecture doesn't have support for the livepatch consistency model.\n");
+ pr_warn("The livepatch transition may never complete.\n");
}
-
mutex_lock(&klp_mutex);
ret = klp_init_patch_early(patch);
diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c
index 9c89ae8b337a..c53370d596be 100644
--- a/kernel/livepatch/transition.c
+++ b/kernel/livepatch/transition.c
@@ -202,15 +202,15 @@ void klp_update_patch_state(struct task_struct *task)
* Determine whether the given stack trace includes any references to a
* to-be-patched or to-be-unpatched function.
*/
-static int klp_check_stack_func(struct klp_func *func,
- struct stack_trace *trace)
+static int klp_check_stack_func(struct klp_func *func, unsigned long *entries,
+ unsigned int nr_entries)
{
unsigned long func_addr, func_size, address;
struct klp_ops *ops;
int i;
- for (i = 0; i < trace->nr_entries; i++) {
- address = trace->entries[i];
+ for (i = 0; i < nr_entries; i++) {
+ address = entries[i];
if (klp_target_state == KLP_UNPATCHED) {
/*
@@ -254,29 +254,25 @@ static int klp_check_stack_func(struct klp_func *func,
static int klp_check_stack(struct task_struct *task, char *err_buf)
{
static unsigned long entries[MAX_STACK_ENTRIES];
- struct stack_trace trace;
struct klp_object *obj;
struct klp_func *func;
- int ret;
+ int ret, nr_entries;
- trace.skip = 0;
- trace.nr_entries = 0;
- trace.max_entries = MAX_STACK_ENTRIES;
- trace.entries = entries;
- ret = save_stack_trace_tsk_reliable(task, &trace);
+ ret = stack_trace_save_tsk_reliable(task, entries, ARRAY_SIZE(entries));
WARN_ON_ONCE(ret == -ENOSYS);
- if (ret) {
+ if (ret < 0) {
snprintf(err_buf, STACK_ERR_BUF_SIZE,
"%s: %s:%d has an unreliable stack\n",
__func__, task->comm, task->pid);
return ret;
}
+ nr_entries = ret;
klp_for_each_object(klp_transition_patch, obj) {
if (!obj->patched)
continue;
klp_for_each_func(obj, func) {
- ret = klp_check_stack_func(func, &trace);
+ ret = klp_check_stack_func(func, entries, nr_entries);
if (ret) {
snprintf(err_buf, STACK_ERR_BUF_SIZE,
"%s: %s:%d is sleeping on function %s\n",
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-05 02:32:01 +0300