[PATCH AUTOSEL 5.0 079/317] nvme-rdma: fix a NULL deref when an admin connect times out

From: Sasha Levin
Date: Wed May 22 2019 - 15:56:04 EST


From: Sagi Grimberg <sagi@xxxxxxxxxxx>

[ Upstream commit 1007709d7d06fab09bf2d007657575958676282b ]

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@xxxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/nvme/host/rdma.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
index 52abc3a6de129..1b1645a77daf5 100644
--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -922,8 +922,9 @@ 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);
}
@@ -934,8 +935,9 @@ 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);
--
2.20.1