netdev - [PATCH v2 net-next] tcp: expose sk_state in tcp_retransmit

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 24 Sep 2018 20:57:29 +0800
From:   Yafang Shao <laoar.shao@...il.com>
To:     edumazet@...gle.com, davem@...emloft.net
Cc:     netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        Yafang Shao <laoar.shao@...il.com>
Subject: [PATCH v2 net-next] tcp: expose sk_state in tcp_retransmit_skb tracepoint

After sk_state exposed, we can get in which state this retransmission
occurs. That could give us more detail for dignostic.
For example, if this retransmission occurs in SYN_SENT state, it may
also indicates that the syn packet may be dropped on the remote peer due
to syn backlog queue full and then we could check the remote peer.

BTW,SYNACK retransmission is traced in tcp_retransmit_synack tracepoint.

Signed-off-by: Yafang Shao <laoar.shao@...il.com>
---
 include/trace/events/tcp.h | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/include/trace/events/tcp.h b/include/trace/events/tcp.h
index ac55b32..2bc9960 100644
--- a/include/trace/events/tcp.h
+++ b/include/trace/events/tcp.h
@@ -56,6 +56,7 @@
 	TP_STRUCT__entry(
 		__field(const void *, skbaddr)
 		__field(const void *, skaddr)
+		__field(int, state)
 		__field(__u16, sport)
 		__field(__u16, dport)
 		__array(__u8, saddr, 4)
@@ -70,6 +71,7 @@
 
 		__entry->skbaddr = skb;
 		__entry->skaddr = sk;
+		__entry->state = sk->sk_state;
 
 		__entry->sport = ntohs(inet->inet_sport);
 		__entry->dport = ntohs(inet->inet_dport);
@@ -84,9 +86,10 @@
 			      sk->sk_v6_rcv_saddr, sk->sk_v6_daddr);
 	),
 
-	TP_printk("sport=%hu dport=%hu saddr=%pI4 daddr=%pI4 saddrv6=%pI6c daddrv6=%pI6c",
+	TP_printk("sport=%hu dport=%hu saddr=%pI4 daddr=%pI4 saddrv6=%pI6c daddrv6=%pI6c state=%s\n",
 		  __entry->sport, __entry->dport, __entry->saddr, __entry->daddr,
-		  __entry->saddr_v6, __entry->daddr_v6)
+		  __entry->saddr_v6, __entry->daddr_v6,
+		  show_tcp_state_name(__entry->state))
 );
 
 DEFINE_EVENT(tcp_event_sk_skb, tcp_retransmit_skb,
-- 
1.8.3.1