From: Jan Kara jack@suse.cz
commit c70c176ff8c3ff0ac6ef9a831cd591ea9a66bd1a upstream.
Make the function available for outside use and fortify it against NULL kobject.
CC: Greg Kroah-Hartman gregkh@linuxfoundation.org Reviewed-by: Bart Van Assche bart.vanassche@sandisk.com Acked-by: Tejun Heo tj@kernel.org Signed-off-by: Jan Kara jack@suse.cz Signed-off-by: Jens Axboe axboe@fb.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- include/linux/kobject.h | 2 ++ lib/kobject.c | 5 ++++- 2 files changed, 6 insertions(+), 1 deletion(-)
--- a/include/linux/kobject.h +++ b/include/linux/kobject.h @@ -108,6 +108,8 @@ extern int __must_check kobject_rename(s extern int __must_check kobject_move(struct kobject *, struct kobject *);
extern struct kobject *kobject_get(struct kobject *kobj); +extern struct kobject * __must_check kobject_get_unless_zero( + struct kobject *kobj); extern void kobject_put(struct kobject *kobj);
extern const void *kobject_namespace(struct kobject *kobj); --- a/lib/kobject.c +++ b/lib/kobject.c @@ -599,12 +599,15 @@ struct kobject *kobject_get(struct kobje } EXPORT_SYMBOL(kobject_get);
-static struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj) +struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj) { + if (!kobj) + return NULL; if (!kref_get_unless_zero(&kobj->kref)) kobj = NULL; return kobj; } +EXPORT_SYMBOL(kobject_get_unless_zero);
/* * kobject_cleanup - free kobject resources.