From fcf73a804c7d6bbf0ea63531c6122aa363852e04 Mon Sep 17 00:00:00 2001 From: Israel Rukshin Date: Wed, 6 Oct 2021 08:09:44 +0000 Subject: [PATCH] nvmet-rdma: fix use-after-free when a port is removed When removing a port, all its controllers are being removed, but there are queues on the port that doesn't belong to any controller (during connection time). This causes a use-after-free bug for any command that dereferences req->port (like in nvmet_alloc_ctrl). Those queues should be destroyed before freeing the port via configfs. Destroy the remaining queues after the RDMA-CM was destroyed guarantees that no new queue will be created. Signed-off-by: Israel Rukshin Reviewed-by: Max Gurtovoy Signed-off-by: Christoph Hellwig --- drivers/nvme/target/rdma.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c index 38d1f29..6f75e6b 100644 --- a/drivers/nvme/target/rdma.c +++ b/drivers/nvme/target/rdma.c @@ -1819,12 +1819,36 @@ restart: mutex_unlock(&nvmet_rdma_queue_mutex); } +static void nvmet_rdma_destroy_port_queues(struct nvmet_rdma_port *port) +{ + struct nvmet_rdma_queue *queue, *tmp; + struct nvmet_port *nport = port->nport; + + mutex_lock(&nvmet_rdma_queue_mutex); + list_for_each_entry_safe(queue, tmp, &nvmet_rdma_queue_list, + queue_list) { + if (queue->port != nport) + continue; + + list_del_init(&queue->queue_list); + __nvmet_rdma_queue_disconnect(queue); + } + mutex_unlock(&nvmet_rdma_queue_mutex); +} + static void nvmet_rdma_disable_port(struct nvmet_rdma_port *port) { struct rdma_cm_id *cm_id = xchg(&port->cm_id, NULL); if (cm_id) rdma_destroy_id(cm_id); + + /* + * Destroy the remaining queues, which are not belong to any + * controller yet. Do it here after the RDMA-CM was destroyed + * guarantees that no new queue will be created. + */ + nvmet_rdma_destroy_port_queues(port); } static int nvmet_rdma_enable_port(struct nvmet_rdma_port *port) -- 2.7.4