Re: [PATCH net-next v3 2/3] net: icmp: introduce __ping_queue_rcv_skb() to report drop reasons

From: David Ahern
Date: Thu Mar 17 2022 - 02:13:43 EST


On 3/16/22 12:31 AM, menglong8.dong@xxxxxxxxx wrote:
> diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
> index 3ee947557b88..9a1ea6c263f8 100644
> --- a/net/ipv4/ping.c
> +++ b/net/ipv4/ping.c
> @@ -934,16 +934,24 @@ int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
> }
> EXPORT_SYMBOL_GPL(ping_recvmsg);
>
> -int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
> +static enum skb_drop_reason __ping_queue_rcv_skb(struct sock *sk,
> + struct sk_buff *skb)
> {
> + enum skb_drop_reason reason;
> +
> pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
> inet_sk(sk), inet_sk(sk)->inet_num, skb);
> - if (sock_queue_rcv_skb(sk, skb) < 0) {
> - kfree_skb(skb);
> + if (sock_queue_rcv_skb_reason(sk, skb, &reason) < 0) {
> + kfree_skb_reason(skb, reason);
> pr_debug("ping_queue_rcv_skb -> failed\n");
> - return -1;
> + return reason;
> }
> - return 0;
> + return SKB_NOT_DROPPED_YET;
> +}
> +
> +int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
> +{
> + return __ping_queue_rcv_skb(sk, skb) ?: -1;
> }
> EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
>

This is a generic proto callback and you are now changing its return
code in a way that seems to conflict with existing semantics