nvme-rdma: fix a NULL deref when an admin connect times out

If we timeout the admin startup sequence we might not yet have
an I/O tagset allocated which causes the teardown sequence to crash.
Make nvme_tcp_teardown_io_queues safe by not iterating inflight tags
if the tagset wasn't allocated.

Fixes: 4c174e636674 ("nvme-rdma: fix timeout handler")
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
index 11a5eca..e1824c2 100644 (file)
--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -914,8 +914,9 @@ static void nvme_rdma_teardown_admin_queue(struct nvme_rdma_ctrl *ctrl,
 {
        blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
        nvme_rdma_stop_queue(&ctrl->queues[0]);
-       blk_mq_tagset_busy_iter(&ctrl->admin_tag_set, nvme_cancel_request,
-                       &ctrl->ctrl);
+       if (ctrl->ctrl.admin_tagset)
+               blk_mq_tagset_busy_iter(ctrl->ctrl.admin_tagset,
+                       nvme_cancel_request, &ctrl->ctrl);
        blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
        nvme_rdma_destroy_admin_queue(ctrl, remove);
 }
@@ -926,8 +927,9 @@ static void nvme_rdma_teardown_io_queues(struct nvme_rdma_ctrl *ctrl,
        if (ctrl->ctrl.queue_count > 1) {
                nvme_stop_queues(&ctrl->ctrl);
                nvme_rdma_stop_io_queues(ctrl);
-               blk_mq_tagset_busy_iter(&ctrl->tag_set, nvme_cancel_request,
-                               &ctrl->ctrl);
+               if (ctrl->ctrl.tagset)
+                       blk_mq_tagset_busy_iter(ctrl->ctrl.tagset,
+                               nvme_cancel_request, &ctrl->ctrl);
                if (remove)
                        nvme_start_queues(&ctrl->ctrl);
                nvme_rdma_destroy_io_queues(ctrl, remove);