net/virtio: fix crash on null dereference

The rxq/txq for the queue_release callback could be NULL, say when
rte_eth_dev_configure() fails that the queue is not setup at all.

Do a simple NULL check would fix the crash issue.

Fixes: 01ad44fd374f ("net/virtio: split Rx/Tx queue")

Reported-by: Olivier Matz <olivier.matz@6wind.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>

diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index 9aba044..724517e 100644 (file)
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -468,13 +468,19 @@ void
 virtio_dev_rx_queue_release(void *rxq)
 {
        struct virtnet_rx *rxvq = rxq;
-       struct virtqueue *vq = rxvq->vq;
-       /* rxvq is freed when vq is freed, and as mz should be freed after the
+       struct virtqueue *vq;
+       const struct rte_memzone *mz;
+
+       if (rxvq == NULL)
+               return;
+
+       /*
+        * rxvq is freed when vq is freed, and as mz should be freed after the
         * del_queue, so we reserve the mz pointer first.
         */
-       const struct rte_memzone *mz = rxvq->mz;
+       vq = rxvq->vq;
+       mz = rxvq->mz;
 
-       /* no need to free rxq as vq and rxq are allocated together */
        virtio_dev_queue_release(vq);
        rte_memzone_free(mz);
 }
@@ -554,12 +560,20 @@ void
 virtio_dev_tx_queue_release(void *txq)
 {
        struct virtnet_tx *txvq = txq;
-       struct virtqueue *vq = txvq->vq;
-       /* txvq is freed when vq is freed, and as mz should be freed after the
+       struct virtqueue *vq;
+       const struct rte_memzone *mz;
+       const struct rte_memzone *hdr_mz;
+
+       if (txvq == NULL)
+               return;
+
+       /*
+        * txvq is freed when vq is freed, and as mz should be freed after the
         * del_queue, so we reserve the mz pointer first.
         */
-       const struct rte_memzone *hdr_mz = txvq->virtio_net_hdr_mz;
-       const struct rte_memzone *mz = txvq->mz;
+       vq = txvq->vq;
+       mz = txvq->mz;
+       hdr_mz = txvq->virtio_net_hdr_mz;
 
        virtio_dev_queue_release(vq);
        rte_memzone_free(mz);