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 | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 9773691097..781734e9e3 100644
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -262,6 +262,8 @@ 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) {
@@ -271,7 +273,8 @@ 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);
@@ -281,6 +284,8 @@ vhost_user_set_vring_num(struct virtio_net *dev,
return -1;
}
+ if (vq->batch_copy_elems)
+ rte_free(vq->batch_copy_elems);
vq->batch_copy_elems = rte_malloc(NULL,
vq->size * sizeof(struct batch_copy_elem),
RTE_CACHE_LINE_SIZE);
--
2.21.0
