3.16.83-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Jan Kara <jack@xxxxxxx> commit c70c176ff8c3ff0ac6ef9a831cd591ea9a66bd1a upstream. Make the function available for outside use and fortify it against NULL kobject. CC: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Reviewed-by: Bart Van Assche <bart.vanassche@xxxxxxxxxxx> Acked-by: Tejun Heo <tj@xxxxxxxxxx> Signed-off-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- 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 @@ -107,6 +107,8 @@ 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 @@ -581,12 +581,15 @@ struct kobject *kobject_get(struct kobje return kobj; } -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.