[RFC PATCH 1/5] livepatch: Fix kobject memleak

From: Tobin C. Harding
Date: Wed May 01 2019 - 22:40:17 EST


Currently error return from kobject_init_and_add() is not followed by a
call to kobject_put(). This means there is a memory leak.

Add call to kobject_put() in error path of kobject_init_and_add().

Signed-off-by: Tobin C. Harding <tobin@xxxxxxxxxx>
---
kernel/livepatch/core.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index eb0ee10a1981..98295de2172b 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -727,7 +727,9 @@ static int klp_init_func(struct klp_object *obj, struct klp_func *func)
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)
+ if (ret)
+ kobject_put(&func->kobj);
+ else
func->kobj_added = true;

return ret;
@@ -803,8 +805,10 @@ static int klp_init_object(struct klp_patch *patch, struct klp_object *obj)
name = klp_is_module(obj) ? obj->name : "vmlinux";
ret = kobject_init_and_add(&obj->kobj, &klp_ktype_object,
&patch->kobj, "%s", name);
- if (ret)
+ if (ret) {
+ kobject_put(&obj->kobj);
return ret;
+ }
obj->kobj_added = true;

klp_for_each_func(obj, func) {
@@ -862,8 +866,10 @@ static int klp_init_patch(struct klp_patch *patch)

ret = kobject_init_and_add(&patch->kobj, &klp_ktype_patch,
klp_root_kobj, "%s", patch->mod->name);
- if (ret)
+ if (ret) {
+ kobject_put(&patch->kobj);
return ret;
+ }
patch->kobj_added = true;

if (patch->replace) {
--
2.21.0