[PATCH v2 2/5] vhost: fix virtqueue access check in VDUSE setup

[David Marchand]

vring_translate and vring_invalidate change the vq access_ok field.
The access_ok field should only be updated under a (write) lock.

Fixes: a9120db8b98b ("vhost: add VDUSE device startup")
Fixes: ad67c65efda1 ("vhost: add VDUSE device stop")
Cc: sta...@dpdk.org

Signed-off-by: David Marchand <david.march...@redhat.com>
Acked-by: Eelco Chaudron <echau...@redhat.com>
---
Changes since v1:
- moved fix out of patch 3,

---
 lib/vhost/vduse.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/vhost/vduse.c b/lib/vhost/vduse.c
index 080b58f7de..e198eeef64 100644
--- a/lib/vhost/vduse.c
+++ b/lib/vhost/vduse.c
@@ -196,6 +196,7 @@ vduse_vring_setup(struct virtio_net *dev, unsigned int 
index)
                                vq->size * sizeof(struct batch_copy_elem),
                                RTE_CACHE_LINE_SIZE, 0);
 
+       rte_rwlock_write_lock(&vq->access_lock);
        vhost_user_iotlb_rd_lock(vq);
        if (vring_translate(dev, vq))
                VHOST_LOG_CONFIG(dev->ifname, ERR, "Failed to translate vring 
%d addresses\n",
@@ -206,6 +207,7 @@ vduse_vring_setup(struct virtio_net *dev, unsigned int 
index)
                                "Failed to disable guest notifications on vring 
%d\n",
                                index);
        vhost_user_iotlb_rd_unlock(vq);
+       rte_rwlock_write_unlock(&vq->access_lock);
 
        vq_efd.index = index;
        vq_efd.fd = vq->kickfd;
@@ -259,7 +261,9 @@ vduse_vring_cleanup(struct virtio_net *dev, unsigned int 
index)
        close(vq->kickfd);
        vq->kickfd = VIRTIO_UNINITIALIZED_EVENTFD;
 
+       rte_rwlock_write_lock(&vq->access_lock);
        vring_invalidate(dev, vq);
+       rte_rwlock_write_unlock(&vq->access_lock);
 
        rte_free(vq->batch_copy_elems);
        vq->batch_copy_elems = NULL;
-- 
2.42.0