[PATCH v4 1/3] nvme-tcp: store and use the caller's network namespace

[Surabhi Gogte <sgogte@purestorage.com>]

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>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
---
 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 921934028e0b..f916bcca304f 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;
@@ -1858,7 +1859,7 @@ 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) {
@@ -2650,6 +2651,7 @@ 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);
 }
@@ -3048,12 +3050,15 @@ 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);
-- 
2.55.0