[3/4] vhost: fix potential use-after-free for memory region
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Commit Message
Reclaim outstanding zmbufs first before freeing memory regions,
otherwise there could be use-after-free.
Fixes: b0a985d1f340 ("vhost: add dequeue zero copy")
Cc: stable@dpdk.org
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
---
lib/librte_vhost/vhost.h | 6 +++++
lib/librte_vhost/vhost_user.c | 46 +++++++++++++++++++++++++----------
lib/librte_vhost/virtio_net.c | 6 -----
3 files changed, 39 insertions(+), 19 deletions(-)
Comments
On 2/22/19 3:42 AM, Tiwei Bie wrote:
> Reclaim outstanding zmbufs first before freeing memory regions,
> otherwise there could be use-after-free.
>
> Fixes: b0a985d1f340 ("vhost: add dequeue zero copy")
> Cc:stable@dpdk.org
>
> Signed-off-by: Tiwei Bie<tiwei.bie@intel.com>
> ---
> lib/librte_vhost/vhost.h | 6 +++++
> lib/librte_vhost/vhost_user.c | 46 +++++++++++++++++++++++++----------
> lib/librte_vhost/virtio_net.c | 6 -----
> 3 files changed, 39 insertions(+), 19 deletions(-)
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Thanks,
Maxime
@@ -769,4 +769,10 @@ mbuf_is_consumed(struct rte_mbuf *m)
return true;
}
+static __rte_always_inline void
+put_zmbuf(struct zcopy_mbuf *zmbuf)
+{
+ zmbuf->in_use = 0;
+}
+
#endif /* _VHOST_NET_CDEV_H_ */
@@ -93,15 +93,47 @@ get_blk_size(int fd)
return ret == -1 ? (uint64_t)-1 : (uint64_t)stat.st_blksize;
}
+/*
+ * Reclaim all the outstanding zmbufs for a virtqueue.
+ */
+static void
+drain_zmbuf_list(struct vhost_virtqueue *vq)
+{
+ struct zcopy_mbuf *zmbuf, *next;
+
+ for (zmbuf = TAILQ_FIRST(&vq->zmbuf_list);
+ zmbuf != NULL; zmbuf = next) {
+ next = TAILQ_NEXT(zmbuf, next);
+
+ while (!mbuf_is_consumed(zmbuf->mbuf))
+ usleep(1000);
+
+ TAILQ_REMOVE(&vq->zmbuf_list, zmbuf, next);
+ restore_mbuf(zmbuf->mbuf);
+ rte_pktmbuf_free(zmbuf->mbuf);
+ put_zmbuf(zmbuf);
+ vq->nr_zmbuf -= 1;
+ }
+}
+
static void
free_mem_region(struct virtio_net *dev)
{
uint32_t i;
struct rte_vhost_mem_region *reg;
+ struct vhost_virtqueue *vq;
if (!dev || !dev->mem)
return;
+ if (dev->dequeue_zero_copy) {
+ for (i = 0; i < dev->nr_vring; i++) {
+ vq = dev->virtqueue[i];
+ if (vq)
+ drain_zmbuf_list(vq);
+ }
+ }
+
for (i = 0; i < dev->mem->nregions; i++) {
reg = &dev->mem->regions[i];
if (reg->host_user_addr) {
@@ -1212,19 +1244,7 @@ vhost_user_set_vring_kick(struct virtio_net **pdev, struct VhostUserMsg *msg,
static void
free_zmbufs(struct vhost_virtqueue *vq)
{
- struct zcopy_mbuf *zmbuf, *next;
-
- for (zmbuf = TAILQ_FIRST(&vq->zmbuf_list);
- zmbuf != NULL; zmbuf = next) {
- next = TAILQ_NEXT(zmbuf, next);
-
- while (!mbuf_is_consumed(zmbuf->mbuf))
- usleep(1000);
-
- restore_mbuf(zmbuf->mbuf);
- rte_pktmbuf_free(zmbuf->mbuf);
- TAILQ_REMOVE(&vq->zmbuf_list, zmbuf, next);
- }
+ drain_zmbuf_list(vq);
rte_free(vq->zmbufs);
}
@@ -1063,12 +1063,6 @@ vhost_dequeue_offload(struct virtio_net_hdr *hdr, struct rte_mbuf *m)
}
}
-static __rte_always_inline void
-put_zmbuf(struct zcopy_mbuf *zmbuf)
-{
- zmbuf->in_use = 0;
-}
-
static __rte_always_inline int
copy_desc_to_mbuf(struct virtio_net *dev, struct vhost_virtqueue *vq,
struct buf_vector *buf_vec, uint16_t nr_vec,