[PATCH v2 3/3] nvme-rdma: fix possible use-after-free in transport error_recovery work

[Hannes Reinecke]

On 2/1/22 13:54, Sagi Grimberg wrote:
> While nvme_rdma_submit_async_event_work is checking the ctrl and queue
> state before preparing the AER command and scheduling io_work, in order
> to fully prevent a race where this check is not reliable the error
> recovery work must flush async_event_work before continuing to destroy
> the admin queue after setting the ctrl state to RESETTING such that
> there is no race .submit_async_event and the error recovery handler
> itself changing the ctrl state.
> 
> Signed-off-by: Sagi Grimberg <sagi at grimberg.me>
> ---
>   drivers/nvme/host/rdma.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
> index 850f84d204d0..9c55e4be8a39 100644
> --- a/drivers/nvme/host/rdma.c
> +++ b/drivers/nvme/host/rdma.c
> @@ -1200,6 +1200,7 @@ static void nvme_rdma_error_recovery_work(struct work_struct *work)
>   			struct nvme_rdma_ctrl, err_work);
>   
>   	nvme_stop_keep_alive(&ctrl->ctrl);
> +	flush_work(&ctrl->ctrl.async_event_work);
>   	nvme_rdma_teardown_io_queues(ctrl, false);
>   	nvme_start_queues(&ctrl->ctrl);
>   	nvme_rdma_teardown_admin_queue(ctrl, false);

Reviewed-by: Hannes Reinecke <hare at suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		           Kernel Storage Architect
hare at suse.de			                  +49 911 74053 688
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