From: Xianting Tian Date: Tue, 22 Sep 2020 06:25:17 +0000 (+0800) Subject: nvme-pci: fix NULL req in completion handler X-Git-Tag: v5.9-rc7~10^2~1^2~2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=50b7c24390a53c78de546215282fb52980f1d7b7;p=thirdparty%2Fkernel%2Flinux.git nvme-pci: fix NULL req in completion handler Currently, we use nvmeq->q_depth as the upper limit for a valid tag in nvme_handle_cqe(), it is not correct. Because the available tag number is recorded in tagset, which is not equal to nvmeq->q_depth. The nvme driver registers interrupts for queues before initializing the tagset, because it uses the number of successful request_irq() calls to configure the tagset parameters. This allows a race condition with the current tag validity check if the controller happens to produce an interrupt with a corrupted CQE before the tagset is initialized. Replace the driver's indirect tag check with the one already provided by the block layer. Signed-off-by: Xianting Tian Reviewed-by: Keith Busch Signed-off-by: Christoph Hellwig --- diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index d31e298669a9b..d286c267869dd 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -940,13 +940,6 @@ static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx) struct nvme_completion *cqe = &nvmeq->cqes[idx]; struct request *req; - if (unlikely(cqe->command_id >= nvmeq->q_depth)) { - dev_warn(nvmeq->dev->ctrl.device, - "invalid id %d completed on queue %d\n", - cqe->command_id, le16_to_cpu(cqe->sq_id)); - return; - } - /* * AEN requests are special as they don't time out and can * survive any kind of queue freeze and often don't respond to @@ -960,6 +953,13 @@ static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx) } req = blk_mq_tag_to_rq(nvme_queue_tagset(nvmeq), cqe->command_id); + if (unlikely(!req)) { + dev_warn(nvmeq->dev->ctrl.device, + "invalid id %d completed on queue %d\n", + cqe->command_id, le16_to_cpu(cqe->sq_id)); + return; + } + trace_nvme_sq(req, cqe->sq_head, nvmeq->sq_tail); if (!nvme_try_complete_req(req, cqe->status, cqe->result)) nvme_pci_complete_rq(req);