From bcd1665e3569b0a6f569514f023a41fc7df0b4a3 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Wed, 7 Nov 2018 12:38:30 +0100 Subject: [PATCH] udp: add support for UDP_GRO cmsg When UDP GRO is enabled, the UDP_GRO cmsg will carry the ingress datagram size. User-space can use such info to compute the original packets layout. Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller --- include/linux/udp.h | 11 +++++++++++ net/ipv4/udp.c | 4 ++++ net/ipv6/udp.c | 3 +++ 3 files changed, 18 insertions(+) diff --git a/include/linux/udp.h b/include/linux/udp.h index f613b329852e..e23d5024f42f 100644 --- a/include/linux/udp.h +++ b/include/linux/udp.h @@ -121,6 +121,17 @@ static inline bool udp_get_no_check6_rx(struct sock *sk) return udp_sk(sk)->no_check6_rx; } +static inline void udp_cmsg_recv(struct msghdr *msg, struct sock *sk, + struct sk_buff *skb) +{ + int gso_size; + + if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) { + gso_size = skb_shinfo(skb)->gso_size; + put_cmsg(msg, SOL_UDP, UDP_GRO, sizeof(gso_size), &gso_size); + } +} + #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 9fc08b098ced..dddc6fe90f51 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1711,6 +1711,10 @@ try_again: memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); *addr_len = sizeof(*sin); } + + if (udp_sk(sk)->gro_enabled) + udp_cmsg_recv(msg, sk, skb); + if (inet->cmsg_flags) ip_cmsg_recv_offset(msg, sk, skb, sizeof(struct udphdr), off); diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index bdf7e071a63b..4c79dc5329bc 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -417,6 +417,9 @@ try_again: *addr_len = sizeof(*sin6); } + if (udp_sk(sk)->gro_enabled) + udp_cmsg_recv(msg, sk, skb); + if (np->rxopt.all) ip6_datagram_recv_common_ctl(sk, msg, skb);