Re: [PATCH v3 1/3] nvme-tcp: store and use the caller's network namespace

[Hannes Reinecke <hare@suse.de>]

On 9/10/26 10:28 PM, Surabhi Gogte wrote:
> nvme_tcp_alloc_queue() creates each socket using
> current->nsproxy->net_ns, which is correct for the initial connect that
> runs in userspace context. However, the reconnect and error recovery
> paths run from a workqueue where current netns is a kernel thread in
> init_net, so sockets created during reconnect end up in a different
> namespace than the one the controller was originally connected from.
> 
> Fix this by capturing the caller's network namespace at controller
> allocation time. Use ctrl->net for all socket creation so that every
> queue, on initial connect, reset, or reconnect, is created in the same
> namespace.
> 
> Fixes: 3f2304f8c6d6 ("nvme-tcp: add NVMe over TCP host driver")
> Signed-off-by: Surabhi Gogte <sgogte@purestorage.com>
> ---
>   drivers/nvme/host/tcp.c | 7 ++++++-
>   1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
> index 5fda9661bdb7..8e5e22febe2a 100644
> --- a/drivers/nvme/host/tcp.c
> +++ b/drivers/nvme/host/tcp.c
> @@ -171,6 +171,7 @@ struct nvme_tcp_ctrl {
>   	struct delayed_work	connect_work;
>   	struct nvme_tcp_request async_req;
>   	u32			io_queues[HCTX_MAX_TYPES];
> +	struct net		*net;
>   };
>   
>   static struct workqueue_struct *nvme_tcp_wq;
> @@ -1846,7 +1847,7 @@ static int nvme_tcp_alloc_queue(struct nvme_ctrl *nctrl, int qid,
>   		queue->cmnd_capsule_len = sizeof(struct nvme_command) +
>   						NVME_TCP_ADMIN_CCSZ;
>   
> -	ret = sock_create_kern(current->nsproxy->net_ns,
> +	ret = sock_create_kern(ctrl->net,
>   			ctrl->addr.ss_family, SOCK_STREAM,
>   			IPPROTO_TCP, &queue->sock);
>   	if (ret) {
> @@ -2638,6 +2639,7 @@ static void nvme_tcp_free_ctrl(struct nvme_ctrl *nctrl)
>   
>   	nvmf_free_options(nctrl->opts);
>   free_ctrl:
> +	put_net(ctrl->net);
>   	kfree(ctrl->queues);
>   	kfree(ctrl);
>   }
> @@ -3036,12 +3038,15 @@ static struct nvme_tcp_ctrl *nvme_tcp_alloc_ctrl(struct device *dev,
>   		goto out_free_ctrl;
>   	}
>   
> +	ctrl->net = get_net(current->nsproxy->net_ns);
> +
>   	ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_tcp_ctrl_ops, 0);
>   	if (ret)
>   		goto out_kfree_queues;
>   
>   	return ctrl;
>   out_kfree_queues:
> +	put_net(ctrl->net);
>   	kfree(ctrl->queues);
>   out_free_ctrl:
>   	kfree(ctrl);

Reviewed-by: Hannes Reinecke <hare@kernel.org>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
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