[PATCH] kobject: Safe return of kobject_get_path with NULL

From: Christian Löhle
Date: Wed Jun 23 2021 - 10:47:42 EST


Prevent NULL dereference within get_kobj_path_length

Calling kobject_get_path could provoke a NULL dereference
if NULL was passed. while fill_kobj_path will return
with a sane 0 for NULL, kobjet_get_path_length did not.

Signed-off-by: Christian Loehle <cloehle@xxxxxxxxxxxxxx>
---
lib/kobject.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/lib/kobject.c b/lib/kobject.c
index ea53b30cf483..735159c13a94 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -130,6 +130,8 @@ static int get_kobj_path_length(struct kobject *kobj)
{
int length = 1;
struct kobject *parent = kobj;
+ if (!kobj)
+ return 0;

/* walk up the ancestors until we hit the one pointing to the
* root.
--
2.32.0

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