From: Prabhath Sajeepa <psajeepa@xxxxxxxxxxxxxxx> [ Upstream commit 9134ae2a2546cb96abddcd4469a79c77ee3a4480 ] The timeout of identify cmd, which is invoked as part of admin queue creation, can result in freeing of async event data both in nvme_rdma_timeout handler and error handling path of nvme_rdma_configure_admin queue thus causing NULL pointer reference. Call Trace: ? nvme_rdma_setup_ctrl+0x223/0x800 [nvme_rdma] nvme_rdma_create_ctrl+0x2ba/0x3f7 [nvme_rdma] nvmf_dev_write+0xa54/0xcc6 [nvme_fabrics] __vfs_write+0x1b/0x40 vfs_write+0xb2/0x1b0 ksys_write+0x61/0xd0 __x64_sys_write+0x1a/0x20 do_syscall_64+0x60/0x1e0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reviewed-by: Roland Dreier <roland@xxxxxxxxxxxxxxx> Reviewed-by: Max Gurtovoy <maxg@xxxxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Prabhath Sajeepa <psajeepa@xxxxxxxxxxxxxxx> Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/nvme/host/rdma.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c index 4ff51da3b13fa..73e8475ddc8ab 100644 --- a/drivers/nvme/host/rdma.c +++ b/drivers/nvme/host/rdma.c @@ -850,9 +850,11 @@ out_free_tagset: if (new) blk_mq_free_tag_set(ctrl->ctrl.admin_tagset); out_free_async_qe: - nvme_rdma_free_qe(ctrl->device->dev, &ctrl->async_event_sqe, - sizeof(struct nvme_command), DMA_TO_DEVICE); - ctrl->async_event_sqe.data = NULL; + if (ctrl->async_event_sqe.data) { + nvme_rdma_free_qe(ctrl->device->dev, &ctrl->async_event_sqe, + sizeof(struct nvme_command), DMA_TO_DEVICE); + ctrl->async_event_sqe.data = NULL; + } out_free_queue: nvme_rdma_free_queue(&ctrl->queues[0]); return error; -- 2.20.1