vhost_user_set_vring_num() performs multiple allocations without checking whether data were previously allocated.
It may cause a denial of service because of the memory leaks that happen if a malicious vhost-user master keeps sending VHOST_USER_SET_VRING_NUM request until the slave runs out of memory. This issue has been assigned CVE-2019-14818 Reported-by: Jason Wang <jasow...@redhat.com> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com> --- lib/librte_vhost/vhost_user.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c index b8f6a9fba5..cebc72f78f 100644 --- a/lib/librte_vhost/vhost_user.c +++ b/lib/librte_vhost/vhost_user.c @@ -204,6 +204,8 @@ vhost_user_set_vring_num(struct virtio_net *dev, vq->nr_zmbuf = 0; vq->last_zmbuf_idx = 0; vq->zmbuf_size = vq->size; + if (vq->zmbufs) + rte_free(vq->zmbufs); vq->zmbufs = rte_zmalloc(NULL, vq->zmbuf_size * sizeof(struct zcopy_mbuf), 0); if (vq->zmbufs == NULL) { @@ -213,7 +215,8 @@ vhost_user_set_vring_num(struct virtio_net *dev, dev->dequeue_zero_copy = 0; } } - + if (vq->shadow_used_ring) + rte_free(vq->shadow_used_ring); vq->shadow_used_ring = rte_malloc(NULL, vq->size * sizeof(struct vring_used_elem), RTE_CACHE_LINE_SIZE); -- 2.21.0