Handling of fragmented virtio-net header and indirect descriptors
tables was implemented to fix CVE-2018-1059. It should never
happen with healthy guests and so are already considered as
unlikely code path.
This patch moves these bits into non-inline dedicated functions
to reduce the I-cache pressure.
Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
---
lib/librte_vhost/vhost.c | 33 +++++++++++
lib/librte_vhost/vhost.h | 35 +-----------
lib/librte_vhost/virtio_net.c | 103 +++++++++++++++++++---------------
3 files changed, 92 insertions(+), 79 deletions(-)
diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
index 4a54ad6bd1..8a4379bc13 100644
--- a/lib/librte_vhost/vhost.c
+++ b/lib/librte_vhost/vhost.c
@@ -201,6 +201,39 @@ __vhost_log_cache_write(struct virtio_net *dev, struct
vhost_virtqueue *vq,
}
+void *
+alloc_copy_ind_table(struct virtio_net *dev, struct vhost_virtqueue *vq,
+ uint64_t desc_addr, uint64_t desc_len)
+{
+ void *idesc;
+ uint64_t src, dst;
+ uint64_t len, remain = desc_len;
+
+ idesc = rte_malloc(__func__, desc_len, 0);
+ if (unlikely(!idesc))
+ return NULL;
+
+ dst = (uint64_t)(uintptr_t)idesc;
+
+ while (remain) {
+ len = remain;
+ src = vhost_iova_to_vva(dev, vq, desc_addr, &len,
+ VHOST_ACCESS_RO);
+ if (unlikely(!src || !len)) {
+ rte_free(idesc);
+ return NULL;
+ }
+
+ rte_memcpy((void *)(uintptr_t)dst, (void *)(uintptr_t)src, len);
+
+ remain -= len;
+ dst += len;
+ desc_addr += len;
+ }
+
+ return idesc;
+}
+
void
cleanup_vq(struct vhost_virtqueue *vq, int destroy)
{
diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index 3ab7b4950f..ab26454e1c 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -488,6 +488,8 @@ void vhost_backend_cleanup(struct virtio_net *dev);
uint64_t __vhost_iova_to_vva(struct virtio_net *dev, struct vhost_virtqueue
*vq,
uint64_t iova, uint64_t *len, uint8_t perm);
+void *alloc_copy_ind_table(struct virtio_net *dev, struct vhost_virtqueue *vq,
+ uint64_t desc_addr, uint64_t desc_len);
int vring_translate(struct virtio_net *dev, struct vhost_virtqueue *vq);
void vring_invalidate(struct virtio_net *dev, struct vhost_virtqueue *vq);
@@ -601,39 +603,6 @@ vhost_vring_call_packed(struct virtio_net *dev, struct
vhost_virtqueue *vq)
eventfd_write(vq->callfd, (eventfd_t)1);
}
-static __rte_always_inline void *
-alloc_copy_ind_table(struct virtio_net *dev, struct vhost_virtqueue *vq,
- uint64_t desc_addr, uint64_t desc_len)
-{
- void *idesc;
- uint64_t src, dst;
- uint64_t len, remain = desc_len;
-
- idesc = rte_malloc(__func__, desc_len, 0);
- if (unlikely(!idesc))
- return 0;
-
- dst = (uint64_t)(uintptr_t)idesc;
-
- while (remain) {
- len = remain;
- src = vhost_iova_to_vva(dev, vq, desc_addr, &len,
- VHOST_ACCESS_RO);
- if (unlikely(!src || !len)) {
- rte_free(idesc);
- return 0;
- }
-
- rte_memcpy((void *)(uintptr_t)dst, (void *)(uintptr_t)src, len);
-
- remain -= len;
- dst += len;
- desc_addr += len;
- }
-
- return idesc;
-}
-
static __rte_always_inline void
free_ind_table(void *idesc)
{
diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 8aeb180016..8ba526c070 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -610,6 +610,36 @@ reserve_avail_buf_packed(struct virtio_net *dev, struct
vhost_virtqueue *vq,
return 0;
}
+static void
+copy_vnet_hdr_to_desc(struct virtio_net *dev, struct vhost_virtqueue *vq,
+ struct buf_vector *buf_vec,
+ struct virtio_net_hdr_mrg_rxbuf *hdr)
+{
+ uint64_t len;
+ uint64_t remain = dev->vhost_hlen;
+ uint64_t src = (uint64_t)(uintptr_t)hdr, dst;
+ uint64_t iova = buf_vec->buf_iova;
+
+ while (remain) {
+ len = RTE_MIN(remain,
+ buf_vec->buf_len);
+ dst = buf_vec->buf_addr;
+ rte_memcpy((void *)(uintptr_t)dst,
+ (void *)(uintptr_t)src,
+ len);
+
+ PRINT_PACKET(dev, (uintptr_t)dst,
+ (uint32_t)len, 0);
+ vhost_log_cache_write(dev, vq,
+ iova, len);
+
+ remain -= len;
+ iova += len;
+ src += len;
+ buf_vec++;
+ }
+}
+
static __rte_always_inline int
copy_mbuf_to_desc(struct virtio_net *dev, struct vhost_virtqueue *vq,
struct rte_mbuf *m, struct buf_vector *buf_vec,
@@ -703,30 +733,7 @@ copy_mbuf_to_desc(struct virtio_net *dev, struct
vhost_virtqueue *vq,
num_buffers);
if (unlikely(hdr == &tmp_hdr)) {
- uint64_t len;
- uint64_t remain = dev->vhost_hlen;
- uint64_t src = (uint64_t)(uintptr_t)hdr, dst;
- uint64_t iova = buf_vec[0].buf_iova;
- uint16_t hdr_vec_idx = 0;
-
- while (remain) {
- len = RTE_MIN(remain,
- buf_vec[hdr_vec_idx].buf_len);
- dst = buf_vec[hdr_vec_idx].buf_addr;
- rte_memcpy((void *)(uintptr_t)dst,
- (void *)(uintptr_t)src,
- len);
-
- PRINT_PACKET(dev, (uintptr_t)dst,
- (uint32_t)len, 0);
- vhost_log_cache_write(dev, vq,
- iova, len);
-
- remain -= len;
- iova += len;
- src += len;
- hdr_vec_idx++;
- }
+ copy_vnet_hdr_to_desc(dev, vq, buf_vec, hdr);
} else {
PRINT_PACKET(dev, (uintptr_t)hdr_addr,
dev->vhost_hlen, 0);
@@ -1063,6 +1070,31 @@ vhost_dequeue_offload(struct virtio_net_hdr *hdr, struct
rte_mbuf *m)
}
}
+static void
+copy_vnet_hdr_from_desc(struct virtio_net_hdr *hdr,
+ struct buf_vector *buf_vec)
+{
+ uint64_t len;
+ uint64_t remain = sizeof(struct virtio_net_hdr);
+ uint64_t src;
+ uint64_t dst = (uint64_t)(uintptr_t)&hdr;
+
+ /*
+ * No luck, the virtio-net header doesn't fit
+ * in a contiguous virtual area.
+ */
+ while (remain) {
+ len = RTE_MIN(remain, buf_vec->buf_len);
+ src = buf_vec->buf_addr;
+ rte_memcpy((void *)(uintptr_t)dst,
+ (void *)(uintptr_t)src, len);
+
+ remain -= len;
+ dst += len;
+ buf_vec++;
+ }
+}
+
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,
@@ -1094,28 +1126,7 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct
vhost_virtqueue *vq,
if (virtio_net_with_host_offload(dev)) {
if (unlikely(buf_len < sizeof(struct virtio_net_hdr))) {
- uint64_t len;
- uint64_t remain = sizeof(struct virtio_net_hdr);
- uint64_t src;
- uint64_t dst = (uint64_t)(uintptr_t)&tmp_hdr;
- uint16_t hdr_vec_idx = 0;
-
- /*
- * No luck, the virtio-net header doesn't fit
- * in a contiguous virtual area.
- */
- while (remain) {
- len = RTE_MIN(remain,
- buf_vec[hdr_vec_idx].buf_len);
- src = buf_vec[hdr_vec_idx].buf_addr;
- rte_memcpy((void *)(uintptr_t)dst,
- (void *)(uintptr_t)src, len);
-
- remain -= len;
- dst += len;
- hdr_vec_idx++;
- }
-
+ copy_vnet_hdr_from_desc(&tmp_hdr, buf_vec);
hdr = &tmp_hdr;
} else {
hdr = (struct virtio_net_hdr *)((uintptr_t)buf_addr);
--
2.21.0
