nvmet-rdma: Fix a possible uninitialized variable dereference

When handling a new recv command, we grab a new rsp resource and
check for the queue state being live. In case the queue is not in
live state, we simply restore the rsp back to the free list. However
in this flow we didn't set rsp->queue yet, so we cannot dereference it.

Instead, make sure to initialize rsp->queue (and other rsp members)
as soon as possible so we won't reference uninitialized variables.

Reported-by: Yi Zhang <yizhan@redhat.com>
Reported-by: Raju Rangoju <rajur@chelsio.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c
index 9aa1da3778b3ac1d2262bfe9b845b65b9cd942d9..ecc4fe8625612442ded6a554e762d029b908c8dc 100644 (file)
--- a/drivers/nvme/target/rdma.c
+++ b/drivers/nvme/target/rdma.c
@@ -703,11 +703,6 @@ static void nvmet_rdma_handle_command(struct nvmet_rdma_queue *queue,
 {
        u16 status;
 
-       cmd->queue = queue;
-       cmd->n_rdma = 0;
-       cmd->req.port = queue->port;
-
-
        ib_dma_sync_single_for_cpu(queue->dev->device,
                cmd->cmd->sge[0].addr, cmd->cmd->sge[0].length,
                DMA_FROM_DEVICE);
@@ -760,9 +755,12 @@ static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc)
 
        cmd->queue = queue;
        rsp = nvmet_rdma_get_rsp(queue);
+       rsp->queue = queue;
        rsp->cmd = cmd;
        rsp->flags = 0;
        rsp->req.cmd = cmd->nvme_cmd;
+       rsp->req.port = queue->port;
+       rsp->n_rdma = 0;
 
        if (unlikely(queue->state != NVMET_RDMA_Q_LIVE)) {
                unsigned long flags;