nvmet-rdma: fix double free of rdma queue

In case rdma accept fails at nvmet_rdma_queue_connect(), release work is
scheduled. Later on, a new RDMA CM event may arrive since we didn't
destroy the cm-id and call nvmet_rdma_queue_connect_fail(), which
schedule another release work. This will cause calling
nvmet_rdma_free_queue twice. To fix this we implicitly destroy the cm_id
with non-zero ret code, which guarantees that new rdma_cm events will
not arrive afterwards. Also add a qp pointer to nvmet_rdma_queue
structure, so we can use it when the cm_id pointer is NULL or was
destroyed.

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Suggested-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Israel Rukshin 2020-04-07 11:02:28 +00:00 committed by Christoph Hellwig
parent 8c5c660529
commit 21f9024355
1 changed files with 18 additions and 12 deletions

View File

@ -78,6 +78,7 @@ enum nvmet_rdma_queue_state {
struct nvmet_rdma_queue {
struct rdma_cm_id *cm_id;
struct ib_qp *qp;
struct nvmet_port *port;
struct ib_cq *cq;
atomic_t sq_wr_avail;
@ -474,7 +475,7 @@ static int nvmet_rdma_post_recv(struct nvmet_rdma_device *ndev,
if (ndev->srq)
ret = ib_post_srq_recv(ndev->srq, &cmd->wr, NULL);
else
ret = ib_post_recv(cmd->queue->cm_id->qp, &cmd->wr, NULL);
ret = ib_post_recv(cmd->queue->qp, &cmd->wr, NULL);
if (unlikely(ret))
pr_err("post_recv cmd failed\n");
@ -513,7 +514,7 @@ static void nvmet_rdma_release_rsp(struct nvmet_rdma_rsp *rsp)
atomic_add(1 + rsp->n_rdma, &queue->sq_wr_avail);
if (rsp->n_rdma) {
rdma_rw_ctx_destroy(&rsp->rw, queue->cm_id->qp,
rdma_rw_ctx_destroy(&rsp->rw, queue->qp,
queue->cm_id->port_num, rsp->req.sg,
rsp->req.sg_cnt, nvmet_data_dir(&rsp->req));
}
@ -597,7 +598,7 @@ static void nvmet_rdma_read_data_done(struct ib_cq *cq, struct ib_wc *wc)
WARN_ON(rsp->n_rdma <= 0);
atomic_add(rsp->n_rdma, &queue->sq_wr_avail);
rdma_rw_ctx_destroy(&rsp->rw, queue->cm_id->qp,
rdma_rw_ctx_destroy(&rsp->rw, queue->qp,
queue->cm_id->port_num, rsp->req.sg,
rsp->req.sg_cnt, nvmet_data_dir(&rsp->req));
rsp->n_rdma = 0;
@ -752,7 +753,7 @@ static bool nvmet_rdma_execute_command(struct nvmet_rdma_rsp *rsp)
}
if (nvmet_rdma_need_data_in(rsp)) {
if (rdma_rw_ctx_post(&rsp->rw, queue->cm_id->qp,
if (rdma_rw_ctx_post(&rsp->rw, queue->qp,
queue->cm_id->port_num, &rsp->read_cqe, NULL))
nvmet_req_complete(&rsp->req, NVME_SC_DATA_XFER_ERROR);
} else {
@ -1038,6 +1039,7 @@ static int nvmet_rdma_create_queue_ib(struct nvmet_rdma_queue *queue)
pr_err("failed to create_qp ret= %d\n", ret);
goto err_destroy_cq;
}
queue->qp = queue->cm_id->qp;
atomic_set(&queue->sq_wr_avail, qp_attr.cap.max_send_wr);
@ -1066,11 +1068,10 @@ static int nvmet_rdma_create_queue_ib(struct nvmet_rdma_queue *queue)
static void nvmet_rdma_destroy_queue_ib(struct nvmet_rdma_queue *queue)
{
struct ib_qp *qp = queue->cm_id->qp;
ib_drain_qp(qp);
rdma_destroy_id(queue->cm_id);
ib_destroy_qp(qp);
ib_drain_qp(queue->qp);
if (queue->cm_id)
rdma_destroy_id(queue->cm_id);
ib_destroy_qp(queue->qp);
ib_free_cq(queue->cq);
}
@ -1305,9 +1306,12 @@ static int nvmet_rdma_queue_connect(struct rdma_cm_id *cm_id,
ret = nvmet_rdma_cm_accept(cm_id, queue, &event->param.conn);
if (ret) {
schedule_work(&queue->release_work);
/* Destroying rdma_cm id is not needed here */
return 0;
/*
* Don't destroy the cm_id in free path, as we implicitly
* destroy the cm_id here with non-zero ret code.
*/
queue->cm_id = NULL;
goto free_queue;
}
mutex_lock(&nvmet_rdma_queue_mutex);
@ -1316,6 +1320,8 @@ static int nvmet_rdma_queue_connect(struct rdma_cm_id *cm_id,
return 0;
free_queue:
nvmet_rdma_free_queue(queue);
put_device:
kref_put(&ndev->ref, nvmet_rdma_free_dev);