summaryrefslogtreecommitdiff
path: root/net/ipv4/tcp.c
diff options
context:
space:
mode:
authorGeliang Tang <tanggeliang@kylinos.cn>2025-07-19 00:06:57 +0200
committerJakub Kicinski <kuba@kernel.org>2025-07-21 17:48:32 -0700
commit51a62199a8aaac0d1645b1dd8e670a6f35aead81 (patch)
tree80483748234733211561e11dbf47e384c2b28dee /net/ipv4/tcp.c
parentedd669057c56966b598a464d6e8c9fc0122a1b1c (diff)
tcp: add tcp_sock_set_maxseg
Add a helper tcp_sock_set_maxseg() to directly set the TCP_MAXSEG sockopt from kernel space. This new helper will be used in the following patch from MPTCP. Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn> Acked-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20250719-net-next-mptcp-tcp_maxseg-v2-2-8c910fbc5307@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv4/tcp.c')
-rw-r--r--net/ipv4/tcp.c23
1 files changed, 14 insertions, 9 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 31149a0ac849..71a956fbfc55 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3751,6 +3751,19 @@ int tcp_set_window_clamp(struct sock *sk, int val)
return 0;
}
+int tcp_sock_set_maxseg(struct sock *sk, int val)
+{
+ /* Values greater than interface MTU won't take effect. However
+ * at the point when this call is done we typically don't yet
+ * know which interface is going to be used
+ */
+ if (val && (val < TCP_MIN_MSS || val > MAX_TCP_WINDOW))
+ return -EINVAL;
+
+ tcp_sk(sk)->rx_opt.user_mss = val;
+ return 0;
+}
+
/*
* Socket option code for TCP.
*/
@@ -3883,15 +3896,7 @@ int do_tcp_setsockopt(struct sock *sk, int level, int optname,
switch (optname) {
case TCP_MAXSEG:
- /* Values greater than interface MTU won't take effect. However
- * at the point when this call is done we typically don't yet
- * know which interface is going to be used
- */
- if (val && (val < TCP_MIN_MSS || val > MAX_TCP_WINDOW)) {
- err = -EINVAL;
- break;
- }
- tp->rx_opt.user_mss = val;
+ err = tcp_sock_set_maxseg(sk, val);
break;
case TCP_NODELAY: