This is a note to let you know that I've just added the patch titled net: add a couple of helpers for iph tot_len to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-add-a-couple-of-helpers-for-iph-tot_len.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 908fc3452bd6b93af1ffe28a9e1db4e1d418dc0c Author: Xin Long <lucien.xin@xxxxxxxxx> Date: Sat Jan 28 10:58:30 2023 -0500 net: add a couple of helpers for iph tot_len [ Upstream commit 058a8f7f73aae1cc22b53fcefec031b9e391b54d ] This patch adds three APIs to replace the iph->tot_len setting and getting in all places where IPv4 BIG TCP packets may reach, they will be used in the following patches. Note that iph_totlen() will be used when iph is not in linear data of the skb. Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx> Reviewed-by: David Ahern <dsahern@xxxxxxxxxx> Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx> Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Stable-dep-of: b2dc32dcba08 ("net/sched: act_ipt: add sanity checks on skb before calling target") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/include/linux/ip.h b/include/linux/ip.h index 3d9c6750af627..d11c25f5030a0 100644 --- a/include/linux/ip.h +++ b/include/linux/ip.h @@ -35,4 +35,25 @@ static inline unsigned int ip_transport_len(const struct sk_buff *skb) { return ntohs(ip_hdr(skb)->tot_len) - skb_network_header_len(skb); } + +static inline unsigned int iph_totlen(const struct sk_buff *skb, const struct iphdr *iph) +{ + u32 len = ntohs(iph->tot_len); + + return (len || !skb_is_gso(skb) || !skb_is_gso_tcp(skb)) ? + len : skb->len - skb_network_offset(skb); +} + +static inline unsigned int skb_ip_totlen(const struct sk_buff *skb) +{ + return iph_totlen(skb, ip_hdr(skb)); +} + +/* IPv4 datagram length is stored into 16bit field (tot_len) */ +#define IP_MAX_MTU 0xFFFFU + +static inline void iph_set_totlen(struct iphdr *iph, unsigned int len) +{ + iph->tot_len = len <= IP_MAX_MTU ? htons(len) : 0; +} #endif /* _LINUX_IP_H */ diff --git a/include/net/route.h b/include/net/route.h index 6e92dd5bcd613..fe00b0a2e4759 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -35,9 +35,6 @@ #include <linux/cache.h> #include <linux/security.h> -/* IPv4 datagram length is stored into 16bit field (tot_len) */ -#define IP_MAX_MTU 0xFFFFU - #define RTO_ONLINK 0x01 #define RT_CONN_FLAGS(sk) (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE))