On 2023/3/9 15:49, Angus Chen wrote: > Don't consume skb if virtqueue_add return -ENOSPC. Is this fixing the same out of space problem caused by xdp xmit as Xuan Zhuo is fixing, or it is fixing a different case? https://lore.kernel.org/netdev/20230308071921-mutt-send-email-mst@xxxxxxxxxx/T/#mc4c5766a59fb8be988bb6a4dfa48f49e58df3ea6 > > Signed-off-by: Angus Chen <angus.chen@xxxxxxxxxxxxxxx> > --- > drivers/net/virtio_net.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index fb5e68ed3ec2..4096ea3d2eb6 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -1980,7 +1980,7 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) > qnum, err); > dev->stats.tx_dropped++; > dev_kfree_skb_any(skb); Returning NETDEV_TX_BUSY will caused stack to requeue the skb and send it again when space is available, but you have freed the skb here, isn't this cause use-after-free problem? > - return NETDEV_TX_OK; > + return (err == -ENOSPC) ? NETDEV_TX_BUSY : NETDEV_TX_OK; > } > > /* Don't wait up for transmitted skbs to be freed. */ >
