[PATCH v2 6/7] vhost: fix missing lock protection in power monitor API

[Maxime Coquelin]

The power monitor get API is missing both access lock
protection and access status check.

Fixes: 34fd4373ce76 ("vhost: add power monitor API")
Cc: stable at dpdk.org

Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
---
 lib/vhost/vhost.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/vhost/vhost.c b/lib/vhost/vhost.c
index a243f88398..d8d74623d4 100644
--- a/lib/vhost/vhost.c
+++ b/lib/vhost/vhost.c
@@ -2121,6 +2121,7 @@ rte_vhost_get_monitor_addr(int vid, uint16_t queue_id,
 {
 	struct virtio_net *dev = get_device(vid);
 	struct vhost_virtqueue *vq;
+	int ret = 0;
 
 	if (dev == NULL)
 		return -1;
@@ -2131,6 +2132,13 @@ rte_vhost_get_monitor_addr(int vid, uint16_t queue_id,
 	if (vq == NULL)
 		return -1;
 
+	rte_rwlock_read_lock(&vq->access_lock);
+
+	if (unlikely(!vq->access_ok)) {
+		ret = -1;
+		goto out_unlock;
+	}
+
 	if (vq_is_packed(dev)) {
 		struct vring_packed_desc *desc;
 		desc = vq->desc_packed;
@@ -2150,7 +2158,10 @@ rte_vhost_get_monitor_addr(int vid, uint16_t queue_id,
 		pmc->match = 0;
 	}
 
-	return 0;
+out_unlock:
+	rte_rwlock_read_unlock(&vq->access_lock);
+
+	return ret;
 }
 
 
-- 
2.41.0