Patch "nvme-rdma: destroy cm id before destroy qp to avoid use after free" has been added to the 5.14-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    nvme-rdma: destroy cm id before destroy qp to avoid use after free

to the 5.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     nvme-rdma-destroy-cm-id-before-destroy-qp-to-avoid-u.patch
and it can be found in the queue-5.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit ef36966ce2f2ac2d2bb2b4f98a5637a050f1b3c4
Author: Ruozhu Li <liruozhu@xxxxxxxxxx>
Date:   Mon Sep 6 11:51:34 2021 +0800

    nvme-rdma: destroy cm id before destroy qp to avoid use after free
    
    [ Upstream commit 9817d763dbe15327b9b3ff4404fa6f27f927e744 ]
    
    We should always destroy cm_id before destroy qp to avoid to get cma
    event after qp was destroyed, which may lead to use after free.
    In RDMA connection establishment error flow, don't destroy qp in cm
    event handler.Just report cm_error to upper level, qp will be destroy
    in nvme_rdma_alloc_queue() after destroy cm id.
    
    Signed-off-by: Ruozhu Li <liruozhu@xxxxxxxxxx>
    Reviewed-by: Max Gurtovoy <mgurtovoy@xxxxxxxxxx>
    Signed-off-by: Christoph Hellwig <hch@xxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
index a68704e39084..042c594bc57e 100644
--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -656,8 +656,8 @@ static void nvme_rdma_free_queue(struct nvme_rdma_queue *queue)
 	if (!test_and_clear_bit(NVME_RDMA_Q_ALLOCATED, &queue->flags))
 		return;
 
-	nvme_rdma_destroy_queue_ib(queue);
 	rdma_destroy_id(queue->cm_id);
+	nvme_rdma_destroy_queue_ib(queue);
 	mutex_destroy(&queue->queue_lock);
 }
 
@@ -1815,14 +1815,10 @@ static int nvme_rdma_conn_established(struct nvme_rdma_queue *queue)
 	for (i = 0; i < queue->queue_size; i++) {
 		ret = nvme_rdma_post_recv(queue, &queue->rsp_ring[i]);
 		if (ret)
-			goto out_destroy_queue_ib;
+			return ret;
 	}
 
 	return 0;
-
-out_destroy_queue_ib:
-	nvme_rdma_destroy_queue_ib(queue);
-	return ret;
 }
 
 static int nvme_rdma_conn_rejected(struct nvme_rdma_queue *queue,
@@ -1916,14 +1912,10 @@ static int nvme_rdma_route_resolved(struct nvme_rdma_queue *queue)
 	if (ret) {
 		dev_err(ctrl->ctrl.device,
 			"rdma_connect_locked failed (%d).\n", ret);
-		goto out_destroy_queue_ib;
+		return ret;
 	}
 
 	return 0;
-
-out_destroy_queue_ib:
-	nvme_rdma_destroy_queue_ib(queue);
-	return ret;
 }
 
 static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
@@ -1954,8 +1946,6 @@ static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
 	case RDMA_CM_EVENT_ROUTE_ERROR:
 	case RDMA_CM_EVENT_CONNECT_ERROR:
 	case RDMA_CM_EVENT_UNREACHABLE:
-		nvme_rdma_destroy_queue_ib(queue);
-		fallthrough;
 	case RDMA_CM_EVENT_ADDR_ERROR:
 		dev_dbg(queue->ctrl->ctrl.device,
 			"CM error event %d\n", ev->event);