nvmet-rdma: fix null dereference under heavy load (5cbab630) · Commits · 戴 / test

Under heavy load if we don't have any pre-allocated rsps left, we dynamically allocate a rsp, but we are not actually allocating memory for nvme_completion (rsp->req.rsp). In such a case, accessing pointer fields (req->rsp->status) in nvmet_req_init() will result in crash. To fix this, allocate the memory for nvme_completion by calling nvmet_rdma_alloc_rsp() Fixes: ("nvmet-rdma:fix possible bogus dereference under heavy load") Cc: <stable@vger.kernel.org> Reviewed-by:

Max Gurtovoy <maxg@mellanox.com> Reviewed-by:

Christoph Hellwig <hch@lst.de> Signed-off-by:

Raju Rangoju <rajur@chelsio.com> Signed-off-by:

Sagi Grimberg <sagi@grimberg.me> Signed-off-by:

Jens Axboe <axboe@kernel.dk>

drivers/nvme/target/rdma.c

+14 −1

Original line number	Diff line number	Diff line
		@@ -139,6 +139,10 @@ static void nvmet_rdma_recv_done(struct ib_cq cq, struct ib_wc wc);
		static void nvmet_rdma_read_data_done(struct ib_cq cq, struct ib_wc wc);
		static void nvmet_rdma_qp_event(struct ib_event event, void priv);
		static void nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue);
		static void nvmet_rdma_free_rsp(struct nvmet_rdma_device *ndev,
		struct nvmet_rdma_rsp *r);
		static int nvmet_rdma_alloc_rsp(struct nvmet_rdma_device *ndev,
		struct nvmet_rdma_rsp *r);

		static const struct nvmet_fabrics_ops nvmet_rdma_ops;

		@@ -182,9 +186,17 @@ nvmet_rdma_get_rsp(struct nvmet_rdma_queue *queue)
		spin_unlock_irqrestore(&queue->rsps_lock, flags);

		if (unlikely(!rsp)) {
		rsp = kmalloc(sizeof(*rsp), GFP_KERNEL);
		int ret;

		rsp = kzalloc(sizeof(*rsp), GFP_KERNEL);
		if (unlikely(!rsp))
		return NULL;
		ret = nvmet_rdma_alloc_rsp(queue->dev, rsp);
		if (unlikely(ret)) {
		kfree(rsp);
		return NULL;
		}

		rsp->allocated = true;
		}

		@@ -197,6 +209,7 @@ nvmet_rdma_put_rsp(struct nvmet_rdma_rsp *rsp)
		unsigned long flags;

		if (unlikely(rsp->allocated)) {
		nvmet_rdma_free_rsp(rsp->queue->dev, rsp);
		kfree(rsp);
		return;
		}

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