Subject: Re: [PATCH net 2/2] virtio_net: free xdp shinfo frags when build_skb_from_xdp_buff() fails

From: "Michael S. Tsirkin" <[email-masked]>
Date: Tue, 14 Mar 2023 05:11:32 -0400

On Tue, Mar 14, 2023 at 04:39:01PM +0800, Xuan Zhuo wrote:
> build_skb_from_xdp_buff() may return NULL, on this
> scene we need to free the frags of xdp shinfo.

s/on this scene/in this case/

> 
> Fixes: fab89bafa95b ("virtio-net: support multi-buffer xdp")
> Signed-off-by: Xuan Zhuo <[email-masked]>

Acked-by: Michael S. Tsirkin <[email-masked]>

> ---
>  drivers/net/virtio_net.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 8ecf7a341d54..d36183be0481 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -1273,9 +1273,12 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
>  
>  		switch (act) {
>  		case XDP_PASS:
> +			head_skb = build_skb_from_xdp_buff(dev, vi, &xdp, xdp_frags_truesz);
> +			if (!head_skb)
> +				goto err_xdp_frags;
> +
>  			if (unlikely(xdp_page != page))
>  				put_page(page);
> -			head_skb = build_skb_from_xdp_buff(dev, vi, &xdp, xdp_frags_truesz);
>  			rcu_read_unlock();
>  			return head_skb;
>  		case XDP_TX:
> -- 
> 2.32.0.3.g01195cf9f