vhost: fix possible out of bound access for indirect descs
Checks
Commit Message
Fix a possible out of bound access which may happen when handling
indirect descs in split ring.
Fixes: 1be4ebb1c464 ("vhost: support indirect descriptor in mergeable Rx")
Cc: stable@dpdk.org
Reported-by: Haiyue Wang <haiyue.wang@intel.com>
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
---
lib/librte_vhost/virtio_net.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
Comments
On 1/21/19 9:12 AM, Tiwei Bie wrote:
> Fix a possible out of bound access which may happen when handling
> indirect descs in split ring.
>
> Fixes: 1be4ebb1c464 ("vhost: support indirect descriptor in mergeable Rx")
> Cc: stable@dpdk.org
>
> Reported-by: Haiyue Wang <haiyue.wang@intel.com>
> Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
> ---
> lib/librte_vhost/virtio_net.c | 8 ++------
> 1 file changed, 2 insertions(+), 6 deletions(-)
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Thanks,
Maxime
On 1/21/19 9:12 AM, Tiwei Bie wrote:
> Fix a possible out of bound access which may happen when handling
> indirect descs in split ring.
>
> Fixes: 1be4ebb1c464 ("vhost: support indirect descriptor in mergeable Rx")
> Cc: stable@dpdk.org
>
> Reported-by: Haiyue Wang <haiyue.wang@intel.com>
> Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
> ---
> lib/librte_vhost/virtio_net.c | 8 ++------
> 1 file changed, 2 insertions(+), 6 deletions(-)
>
Applide to dpdk-next-virtio/master.
Thanks,
Maxime
@@ -310,6 +310,7 @@ fill_vec_buf_split(struct virtio_net *dev, struct vhost_virtqueue *vq,
uint32_t len = 0;
uint64_t dlen;
uint32_t nr_descs = vq->size;
+ uint32_t cnt = 0;
struct vring_desc *descs = vq->desc;
struct vring_desc *idesc = NULL;
@@ -348,12 +349,7 @@ fill_vec_buf_split(struct virtio_net *dev, struct vhost_virtqueue *vq,
}
while (1) {
- if (unlikely(idx >= vq->size)) {
- free_ind_table(idesc);
- return -1;
- }
-
- if (unlikely(nr_descs-- == 0)) {
+ if (unlikely(idx >= nr_descs || cnt++ >= nr_descs)) {
free_ind_table(idesc);
return -1;
}