Commit 5b8f3c8d30a6 ("virtio_net: Add XDP related stats") tries to
count TX XDP stats in virtnet_receive(). This will cause several
issues:
- virtnet_xdp_sq() was called without checking whether or not XDP is
set. This may cause out of bound access when there's no enough txq
for XDP.
- Stats were updated even if there's no XDP/XDP_TX.
Fixing this by reusing virtnet_xdp_xmit() for XDP_TX which can counts
TX XDP counter itself and remove the unnecessary tx stats embedded in
rx stats.
Reported-by: syzbot+604f8271211546f5b3c7@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 5b8f3c8d30a6 ("virtio_net: Add XDP related stats")
Cc: Toshiaki Makita <makita.toshiaki@xxxxxxxxxxxxx>
Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
drivers/net/virtio_net.c | 39 ++++-----------------------------------
1 file changed, 4 insertions(+), 35 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 1880c86..72d3f68 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -105,10 +105,6 @@ struct virtnet_rq_stats {
struct virtnet_rx_stats {
struct virtnet_rq_stat_items rx;
- struct {
- unsigned int xdp_tx;
- unsigned int xdp_tx_drops;
- } tx;
};
#define VIRTNET_SQ_STAT(m) offsetof(struct virtnet_sq_stats, m)
@@ -485,22 +481,6 @@ static struct send_queue *virtnet_xdp_sq(struct virtnet_info *vi)
return &vi->sq[qp];
}
-static int __virtnet_xdp_tx_xmit(struct virtnet_info *vi,
- struct xdp_frame *xdpf)
-{
- struct xdp_frame *xdpf_sent;
- struct send_queue *sq;
- unsigned int len;
-
- sq = virtnet_xdp_sq(vi);
-
- /* Free up any pending old buffers before queueing new ones. */
- while ((xdpf_sent = virtqueue_get_buf(sq->vq, &len)) != NULL)
- xdp_return_frame(xdpf_sent);
-
- return __virtnet_xdp_xmit_one(vi, sq, xdpf);
-}
-
static int virtnet_xdp_xmit(struct net_device *dev,
int n, struct xdp_frame **frames, u32 flags)
{
@@ -707,10 +687,8 @@ static struct sk_buff *receive_small(struct net_device *dev,
xdpf = convert_to_xdp_frame(&xdp);
if (unlikely(!xdpf))
goto err_xdp;
- stats->tx.xdp_tx++;
- err = __virtnet_xdp_tx_xmit(vi, xdpf);
- if (unlikely(err)) {
- stats->tx.xdp_tx_drops++;
+ err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
+ if (unlikely(err < 0)) {
trace_xdp_exception(vi->dev, xdp_prog, act);
goto err_xdp;
}
@@ -879,10 +857,8 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
xdpf = convert_to_xdp_frame(&xdp);
if (unlikely(!xdpf))
goto err_xdp;
- stats->tx.xdp_tx++;
- err = __virtnet_xdp_tx_xmit(vi, xdpf);
- if (unlikely(err)) {
- stats->tx.xdp_tx_drops++;
+ err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
+ if (unlikely(err < 0)) {
trace_xdp_exception(vi->dev, xdp_prog, act);
if (unlikely(xdp_page != page))
put_page(xdp_page);
@@ -1315,7 +1291,6 @@ static int virtnet_receive(struct receive_queue *rq, int budget,
{
struct virtnet_info *vi = rq->vq->vdev->priv;
struct virtnet_rx_stats stats = {};
- struct send_queue *sq;
unsigned int len;
void *buf;
int i;
@@ -1351,12 +1326,6 @@ static int virtnet_receive(struct receive_queue *rq, int budget,
}
u64_stats_update_end(&rq->stats.syncp);
- sq = virtnet_xdp_sq(vi);
- u64_stats_update_begin(&sq->stats.syncp);
- sq->stats.xdp_tx += stats.tx.xdp_tx;
- sq->stats.xdp_tx_drops += stats.tx.xdp_tx_drops;
- u64_stats_update_end(&sq->stats.syncp);
-
return stats.rx.packets;
}
--
2.7.4
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