vhost: validate index in available entries API

This patch validates the queue index parameter, in order
to ensure neither out-of-bound accesses nor NULL pointer
dereferencing happen.

Fixes: a67f286a6596 ("vhost: export queue free entries")
Cc: stable@dpdk.org
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>

diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
index 0c9ba3b..193dafc 100644 (file)
--- a/lib/librte_vhost/vhost.c
+++ b/lib/librte_vhost/vhost.c
@@ -1260,7 +1260,12 @@ rte_vhost_avail_entries(int vid, uint16_t queue_id)
        if (!dev)
                return 0;
 
+       if (queue_id >= VHOST_MAX_VRING)
+               return 0;
+
        vq = dev->virtqueue[queue_id];
+       if (!vq)
+               return 0;
 
        rte_spinlock_lock(&vq->access_lock);