From: Eric Dumazet Date: Thu, 5 Mar 2026 11:48:29 +0000 (+0000) Subject: inet_diag: report delayed ack timer information X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c698f5cc940de5871ea3c65c94f5fd7fbc6844e3;p=thirdparty%2Flinux.git inet_diag: report delayed ack timer information inet_sk_diag_fill() populates r->idiag_timer with the following precedence order: 1 - Retransmit timer. 4 - Probe0 timer. 2 - Keepalive timer. This patch adds a new value, last in the list, if other timers are not active. 5 - Delayed ACK timer. A corresponding iproute2 patch will follow to replace "unknown" with "delack": ESTAB 10 0 [2002:a05:6830:1f86::]:12875 [2002:a05:6830:1f85::]:50438 timer:(unknown,003ms,0) ino:152178 sk:3004 cgroup:unreachable:189 <-> skmem:(r1344,rb12780520,t0,tb262144,f2752,w0,o250,bl0,d0) ts usec_ts ... Also add the following enum in uapi/linux/inet_diag.h as suggested by David Ahern. enum { IDIAG_TIMER_OFF, IDIAG_TIMER_ON, IDIAG_TIMER_KEEPALIVE, IDIAG_TIMER_TIMEWAIT, IDIAG_TIMER_PROBE0, IDIAG_TIMER_DELACK, }; Neal Cardwell suggested to test for ICSK_ACK_TIMER: inet_csk_clear_xmit_timer() does not call sk_stop_timer() because INET_CSK_CLEAR_TIMERS is unset. Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Reviewed-by: Neal Cardwell Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260305114829.2163276-1-edumazet@google.com Signed-off-by: Jakub Kicinski --- diff --git a/include/uapi/linux/inet_diag.h b/include/uapi/linux/inet_diag.h index 86bb2e8b17c9f..21f0d735fbae2 100644 --- a/include/uapi/linux/inet_diag.h +++ b/include/uapi/linux/inet_diag.h @@ -129,6 +129,15 @@ struct inet_diag_msg { __u32 idiag_inode; }; +enum { + IDIAG_TIMER_OFF, + IDIAG_TIMER_ON, + IDIAG_TIMER_KEEPALIVE, + IDIAG_TIMER_TIMEWAIT, + IDIAG_TIMER_PROBE0, + IDIAG_TIMER_DELACK, +}; + /* Extensions */ enum { diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index 9d215485b5c7e..34b77aa87d0a4 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -241,7 +241,7 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, inet_diag_msg_common_fill(r, sk); r->idiag_state = sk->sk_state; - r->idiag_timer = 0; + r->idiag_timer = IDIAG_TIMER_OFF; r->idiag_retrans = 0; r->idiag_expires = 0; @@ -284,20 +284,25 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, if (icsk_pending == ICSK_TIME_RETRANS || icsk_pending == ICSK_TIME_REO_TIMEOUT || icsk_pending == ICSK_TIME_LOSS_PROBE) { - r->idiag_timer = 1; + r->idiag_timer = IDIAG_TIMER_ON; r->idiag_retrans = READ_ONCE(icsk->icsk_retransmits); r->idiag_expires = jiffies_delta_to_msecs(tcp_timeout_expires(sk) - jiffies); } else if (icsk_pending == ICSK_TIME_PROBE0) { - r->idiag_timer = 4; + r->idiag_timer = IDIAG_TIMER_PROBE0; r->idiag_retrans = READ_ONCE(icsk->icsk_probes_out); r->idiag_expires = jiffies_delta_to_msecs(tcp_timeout_expires(sk) - jiffies); } else if (timer_pending(&icsk->icsk_keepalive_timer)) { - r->idiag_timer = 2; + r->idiag_timer = IDIAG_TIMER_KEEPALIVE; r->idiag_retrans = READ_ONCE(icsk->icsk_probes_out); r->idiag_expires = jiffies_delta_to_msecs(icsk->icsk_keepalive_timer.expires - jiffies); + } else if ((READ_ONCE(icsk->icsk_ack.pending) & ICSK_ACK_TIMER) && + timer_pending(&icsk->icsk_delack_timer)) { + r->idiag_timer = IDIAG_TIMER_DELACK; + r->idiag_expires = + jiffies_delta_to_msecs(icsk_delack_timeout(icsk) - jiffies); } if ((ext & (1 << (INET_DIAG_INFO - 1))) && handler->idiag_info_size) { diff --git a/net/ipv4/tcp_diag.c b/net/ipv4/tcp_diag.c index 7935702e394b2..ba1fdbe9807fd 100644 --- a/net/ipv4/tcp_diag.c +++ b/net/ipv4/tcp_diag.c @@ -212,7 +212,7 @@ static int tcp_twsk_diag_fill(struct sock *sk, r->idiag_retrans = 0; r->idiag_state = READ_ONCE(tw->tw_substate); - r->idiag_timer = 3; + r->idiag_timer = IDIAG_TIMER_TIMEWAIT; tmo = tw->tw_timer.expires - jiffies; r->idiag_expires = jiffies_delta_to_msecs(tmo); r->idiag_rqueue = 0; @@ -247,7 +247,7 @@ static int tcp_req_diag_fill(struct sock *sk, struct sk_buff *skb, r = nlmsg_data(nlh); inet_diag_msg_common_fill(r, sk); r->idiag_state = TCP_SYN_RECV; - r->idiag_timer = 1; + r->idiag_timer = IDIAG_TIMER_ON; r->idiag_retrans = READ_ONCE(reqsk->num_retrans); BUILD_BUG_ON(offsetof(struct inet_request_sock, ir_cookie) !=