Re: [PATCH] blk-mq: only unregister sysfs when registration succeeded

[Yu Kuai]

在 2022/11/12 18:44, Yu Kuai 写道:
> Hi,
>
> 在 2022/11/12 19:07, Liu Shixin 写道:
> > kobject_del() must not be called if kobject_add() has not been called.
> > Hence only unregister sysfs when registration succeeded.
>
>  From what I see, the blk_queue_registered() from caller
> blk_unregister_queue() can already prevent that. QUEUE_FLAG_REGISTERED
> will only be set if blk_register_queue() succeed.

I see that the return value of blk_mq_sysfs_register() is not checked
from blk_register_queue(), there will be memleak or uaf from error path.

Hence I think better thing to do is to handle the case that
blk_mq_sysfs_register() faild, and clean up if blk_mq_sysfs_register()
succeed while follow up procedures failed from blk_register_queue().