diff options
| author | Alice Mikityanska <alice@isovalent.com> | 2026-02-05 15:39:14 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-02-06 20:50:03 -0800 |
| commit | b2936b4fd56294e49d6c8e9152ea6c4982757c7d (patch) | |
| tree | 09239f6aac9c4482707e969f395da685a5d6b1f0 /include | |
| parent | 5826eec8710c214f02f253c165d66a230f5a86c3 (diff) | |
net/ipv6: Introduce payload_len helpers
The next commits will transition away from using the hop-by-hop
extension header to encode packet length for BIG TCP. Add wrappers
around ip6->payload_len that return the actual value if it's non-zero,
and calculate it from skb->len if payload_len is set to zero (and a
symmetrical setter).
The new helpers are used wherever the surrounding code supports the
hop-by-hop jumbo header for BIG TCP IPv6, or the corresponding IPv4 code
uses skb_ip_totlen (e.g., in include/net/netfilter/nf_tables_ipv6.h).
No behavioral change in this commit.
Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260205133925.526371-2-alice.kernel@fastmail.im
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/ipv6.h | 22 | ||||
| -rw-r--r-- | include/net/ipv6.h | 2 | ||||
| -rw-r--r-- | include/net/netfilter/nf_tables_ipv6.h | 4 |
3 files changed, 24 insertions, 4 deletions
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h index 20aae8357dd1..57ab6c97ee7e 100644 --- a/include/linux/ipv6.h +++ b/include/linux/ipv6.h @@ -126,6 +126,28 @@ static inline unsigned int ipv6_transport_len(const struct sk_buff *skb) skb_network_header_len(skb); } +static inline unsigned int +ipv6_payload_len(const struct sk_buff *skb, const struct ipv6hdr *ip6) +{ + u32 len = ntohs(ip6->payload_len); + + return (len || !skb_is_gso(skb) || !skb_is_gso_tcp(skb)) ? + len : + skb->len - skb_network_offset(skb) - sizeof(struct ipv6hdr); +} + +static inline unsigned int skb_ipv6_payload_len(const struct sk_buff *skb) +{ + return ipv6_payload_len(skb, ipv6_hdr(skb)); +} + +#define IPV6_MAXPLEN 65535 + +static inline void ipv6_set_payload_len(struct ipv6hdr *ip6, unsigned int len) +{ + ip6->payload_len = len <= IPV6_MAXPLEN ? htons(len) : 0; +} + /* This structure contains results of exthdrs parsing as offsets from skb->nh. diff --git a/include/net/ipv6.h b/include/net/ipv6.h index c27b9d7aeb7c..1c2d6095b050 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -25,8 +25,6 @@ struct ip_tunnel_info; #define SIN6_LEN_RFC2133 24 -#define IPV6_MAXPLEN 65535 - /* * NextHeader field of IPv6 header */ diff --git a/include/net/netfilter/nf_tables_ipv6.h b/include/net/netfilter/nf_tables_ipv6.h index a0633eeaec97..c53ac00bb974 100644 --- a/include/net/netfilter/nf_tables_ipv6.h +++ b/include/net/netfilter/nf_tables_ipv6.h @@ -42,7 +42,7 @@ static inline int __nft_set_pktinfo_ipv6_validate(struct nft_pktinfo *pkt) if (ip6h->version != 6) return -1; - pkt_len = ntohs(ip6h->payload_len); + pkt_len = ipv6_payload_len(pkt->skb, ip6h); skb_len = pkt->skb->len - skb_network_offset(pkt->skb); if (pkt_len + sizeof(*ip6h) > skb_len) return -1; @@ -86,7 +86,7 @@ static inline int nft_set_pktinfo_ipv6_ingress(struct nft_pktinfo *pkt) if (ip6h->version != 6) goto inhdr_error; - pkt_len = ntohs(ip6h->payload_len); + pkt_len = ipv6_payload_len(pkt->skb, ip6h); if (pkt_len + sizeof(*ip6h) > pkt->skb->len) { idev = __in6_dev_get(nft_in(pkt)); __IP6_INC_STATS(nft_net(pkt), idev, IPSTATS_MIB_INTRUNCATEDPKTS); |