4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Israel Rukshin <israelr@xxxxxxxxxxxx> [ Upstream commit 43b92fd27aaef0f529c9321cfebbaec1d7b8f503 ] A NULL deref happens when nvmet_rdma_remove_one() is called more than once (e.g. while connected via 2 ports). The first call frees the queues related to the first ib_device but doesn't remove them from the queue list. While calling nvmet_rdma_remove_one() for the second ib_device it goes over the full queue list again and we get the NULL deref. Fixes: f1d4ef7d ("nvmet-rdma: register ib_client to not deadlock in device removal") Signed-off-by: Israel Rukshin <israelr@xxxxxxxxxxxx> Reviewed-by: Max Gurtovoy <maxg@xxxxxxxxxxxx> Reviewed-by: Sagi Grimberg <sagi@xxxxxxxxxx> Signed-off-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/nvme/target/rdma.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/nvme/target/rdma.c +++ b/drivers/nvme/target/rdma.c @@ -1512,15 +1512,17 @@ static struct nvmet_fabrics_ops nvmet_rd static void nvmet_rdma_remove_one(struct ib_device *ib_device, void *client_data) { - struct nvmet_rdma_queue *queue; + struct nvmet_rdma_queue *queue, *tmp; /* Device is being removed, delete all queues using this device */ mutex_lock(&nvmet_rdma_queue_mutex); - list_for_each_entry(queue, &nvmet_rdma_queue_list, queue_list) { + list_for_each_entry_safe(queue, tmp, &nvmet_rdma_queue_list, + queue_list) { if (queue->dev->device != ib_device) continue; pr_info("Removing queue %d\n", queue->idx); + list_del_init(&queue->queue_list); __nvmet_rdma_queue_disconnect(queue); } mutex_unlock(&nvmet_rdma_queue_mutex);