Re: [PATCH v3 06/18] nvmet-fcloop: sync targetport removal

[Hannes Reinecke <hare@suse.de>]

On 3/18/25 11:40, Daniel Wagner wrote:
> The nvmet-fc uses references on the targetport to ensure no UAFs
> happens. The consequence is that when the targetport is unregistered,
> not all resources are freed immediately. Ensure that all activities from
> the unregister call have been submitted (deassocication) before
> continuing with the shutdown sequence.
> 
> Signed-off-by: Daniel Wagner <wagi@kernel.org>
> ---
>   drivers/nvme/target/fcloop.c | 15 ++++++++++++++-
>   1 file changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/nvme/target/fcloop.c b/drivers/nvme/target/fcloop.c
> index 69121a5f0f280936d1b720e9e994d6e5eb9186ff..cddaa424bb3ff62156cef14c787fdcb33c15d76e 100644
> --- a/drivers/nvme/target/fcloop.c
> +++ b/drivers/nvme/target/fcloop.c
> @@ -239,6 +239,7 @@ struct fcloop_nport {
>   	struct fcloop_rport *rport;
>   	struct fcloop_tport *tport;
>   	struct fcloop_lport *lport;
> +	struct completion tport_unreg_done;
>   	struct list_head nport_list;
>   	refcount_t ref;
>   	u64 node_name;
> @@ -1078,6 +1079,8 @@ fcloop_targetport_delete(struct nvmet_fc_target_port *targetport)
>   	tport->nport->tport = NULL;
>   	spin_unlock_irqrestore(&fcloop_lock, flags);
>   
> +	complete(&tport->nport->tport_unreg_done);
> +
>   	/* nport ref put: tport */
>   	fcloop_nport_put(tport->nport);
>   }
> @@ -1507,7 +1510,17 @@ __unlink_target_port(struct fcloop_nport *nport)
>   static int
>   __targetport_unreg(struct fcloop_nport *nport, struct fcloop_tport *tport)
>   {
> -	return nvmet_fc_unregister_targetport(tport->targetport);
> +	int ret;
> +
> +	init_completion(&nport->tport_unreg_done);
> +
> +	ret = nvmet_fc_unregister_targetport(tport->targetport);
> +	if (ret)
> +		return ret;
> +
> +	wait_for_completion(&nport->tport_unreg_done);
> +
> +	return 0;
>   }
>   
>   static ssize_t
> 
Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
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