Re: [PATCH] nvmet-rdma: Fix use after free

From: Sagi Grimberg
Date: Tue Aug 16 2016 - 09:17:56 EST


Avoid dereferencing the queue pointer in nvmet_rdma_release_queue_work()
after it has been freed by nvmet_rdma_free_queue().

Fixes: d8f7750a08968b10 ("nvmet-rdma: Correctly handle RDMA device hot removal")
Signed-off-by: Vincent Stehlà <vincent.stehle@xxxxxxxxx>
Cc: Sagi Grimberg <sagi@xxxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
---
drivers/nvme/target/rdma.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c
index b4d6485..5de8d0a 100644
--- a/drivers/nvme/target/rdma.c
+++ b/drivers/nvme/target/rdma.c
@@ -978,10 +978,11 @@ static void nvmet_rdma_release_queue_work(struct work_struct *w)
container_of(w, struct nvmet_rdma_queue, release_work);
struct rdma_cm_id *cm_id = queue->cm_id;
struct nvmet_rdma_device *dev = queue->dev;
+ enum nvmet_rdma_queue_state state = queue->state;

nvmet_rdma_free_queue(queue);

- if (queue->state != NVMET_RDMA_IN_DEVICE_REMOVAL)
+ if (state != NVMET_RDMA_IN_DEVICE_REMOVAL)
rdma_destroy_id(cm_id);

kref_put(&dev->ref, nvmet_rdma_free_dev);


Queued for the next round of rc fixes.

Thanks Vincent!