From d94211b8bad3787e0655a67284105f57db728cb1 Mon Sep 17 00:00:00 2001 From: Sagi Grimberg Date: Fri, 26 Jul 2019 10:29:49 -0700 Subject: [PATCH] nvme-rdma: fix possible use-after-free in connect error flow When start_queue fails, we need to make sure to drain the queue cq before freeing the rdma resources because we might still race with the completion path. Have start_queue() error path safely stop the queue. -- [30371.808111] nvme nvme1: Failed reconnect attempt 11 [30371.808113] nvme nvme1: Reconnecting in 10 seconds... [...] [30382.069315] nvme nvme1: creating 4 I/O queues. [30382.257058] nvme nvme1: Connect Invalid SQE Parameter, qid 4 [30382.257061] nvme nvme1: failed to connect queue: 4 ret=386 [30382.305001] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 [30382.305022] IP: qedr_poll_cq+0x8a3/0x1170 [qedr] [30382.305028] PGD 0 P4D 0 [30382.305037] Oops: 0000 [#1] SMP PTI [...] [30382.305153] Call Trace: [30382.305166] ? __switch_to_asm+0x34/0x70 [30382.305187] __ib_process_cq+0x56/0xd0 [ib_core] [30382.305201] ib_poll_handler+0x26/0x70 [ib_core] [30382.305213] irq_poll_softirq+0x88/0x110 [30382.305223] ? sort_range+0x20/0x20 [30382.305232] __do_softirq+0xde/0x2c6 [30382.305241] ? sort_range+0x20/0x20 [30382.305249] run_ksoftirqd+0x1c/0x60 [30382.305258] smpboot_thread_fn+0xef/0x160 [30382.305265] kthread+0x113/0x130 [30382.305273] ? kthread_create_worker_on_cpu+0x50/0x50 [30382.305281] ret_from_fork+0x35/0x40 -- Reported-by: Nicolas Morey-Chaisemartin Reviewed-by: Max Gurtovoy Reviewed-by: Hannes Reinecke Signed-off-by: Sagi Grimberg --- drivers/nvme/host/rdma.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c index a249db5..1a6449b 100644 --- a/drivers/nvme/host/rdma.c +++ b/drivers/nvme/host/rdma.c @@ -562,13 +562,17 @@ out_destroy_cm_id: return ret; } +static void __nvme_rdma_stop_queue(struct nvme_rdma_queue *queue) +{ + rdma_disconnect(queue->cm_id); + ib_drain_qp(queue->qp); +} + static void nvme_rdma_stop_queue(struct nvme_rdma_queue *queue) { if (!test_and_clear_bit(NVME_RDMA_Q_LIVE, &queue->flags)) return; - - rdma_disconnect(queue->cm_id); - ib_drain_qp(queue->qp); + __nvme_rdma_stop_queue(queue); } static void nvme_rdma_free_queue(struct nvme_rdma_queue *queue) @@ -607,11 +611,13 @@ static int nvme_rdma_start_queue(struct nvme_rdma_ctrl *ctrl, int idx) else ret = nvmf_connect_admin_queue(&ctrl->ctrl); - if (!ret) + if (!ret) { set_bit(NVME_RDMA_Q_LIVE, &queue->flags); - else + } else { + __nvme_rdma_stop_queue(queue); dev_info(ctrl->ctrl.device, "failed to connect queue: %d ret=%d\n", idx, ret); + } return ret; } -- 2.7.4