On Fri, Oct 19, 2018 at 04:25:16PM +0200, Paolo Abeni wrote:
> +
> +static inline struct sk_buff *udp_rcv_segment(struct sock *sk,
> + struct sk_buff *skb)
> +{
> + struct sk_buff *segs;
> +
> + /* the GSO CB lays after the UDP one, no need to save and restore any
> + * CB fragment, just initialize it
> + */
> + segs = __skb_gso_segment(skb, NETIF_F_SG, false);
> + if (unlikely(IS_ERR(segs)))
> + kfree_skb(skb);
> + else if (segs)
> + consume_skb(skb);
> + return segs;
> +}
> +
> +
One empty line too much.
> #define udp_portaddr_for_each_entry(__sk, list) \
> hlist_for_each_entry(__sk, list, __sk_common.skc_portaddr_node)
>
> diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
> index 2331ac9de954..0d55145ce9f5 100644
> --- a/net/ipv4/udp.c
> +++ b/net/ipv4/udp.c
> @@ -1909,7 +1909,7 @@ EXPORT_SYMBOL(udp_encap_enable);
> * Note that in the success and error cases, the skb is assumed to
> * have either been requeued or freed.
> */
> -static int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
> +static int udp_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
> {
> struct udp_sock *up = udp_sk(sk);
> int is_udplite = IS_UDPLITE(sk);
> @@ -2012,6 +2012,29 @@ static int udp_queue_rcv_skb(struct sock *sk, struct
> sk_buff *skb)
> return -1;
> }
>
> +void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int
> proto);
> +
> +static int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
> +{
> + struct sk_buff *next, *segs;
> + int ret;
> +
> + if (likely(!udp_unexpected_gso(sk, skb)))
> + return udp_queue_rcv_one_skb(sk, skb);
> +
> + BUILD_BUG_ON(sizeof(struct udp_skb_cb) > SKB_SGO_CB_OFFSET);
> + __skb_push(skb, -skb_mac_offset(skb));
> + segs = udp_rcv_segment(sk, skb);
> + for (skb = segs; skb; skb = next) {
> + next = skb->next;
> + __skb_pull(skb, skb_transport_offset(skb));
> + ret = udp_queue_rcv_one_skb(sk, skb);
udp_queue_rcv_one_skb() starts with doing a xfrm4_policy_check().
Maybe we can do this on the GSO packet instead of the segments.
So far this code is just for handling a corner case, but this might
change.
