[RFC 3/3] tcp: add mib counter to track ts tsecr validation failures
From: Florian Westphal <fw@strlen.de>
Date: 2016-08-18 13:00:09
Subsystem:
networking [general], networking [tcp], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Neal Cardwell, Linus Torvalds
useful to detect packet drop due to enabled tcp_timestamps=2 mode. Signed-off-by: Florian Westphal <fw@strlen.de> --- include/uapi/linux/snmp.h | 1 + net/ipv4/proc.c | 1 + net/ipv4/tcp_input.c | 1 + 3 files changed, 3 insertions(+)
diff --git a/include/uapi/linux/snmp.h b/include/uapi/linux/snmp.h
index 25a9ad8..79916ca 100644
--- a/include/uapi/linux/snmp.h
+++ b/include/uapi/linux/snmp.h@@ -280,6 +280,7 @@ enum LINUX_MIB_TCPKEEPALIVE, /* TCPKeepAlive */ LINUX_MIB_TCPMTUPFAIL, /* TCPMTUPFail */ LINUX_MIB_TCPMTUPSUCCESS, /* TCPMTUPSuccess */ + LINUX_MIB_TCPTSECRFAIL, /* TCPTSecrFail */ __LINUX_MIB_MAX };
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
index 9f665b6..e7667f8 100644
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c@@ -302,6 +302,7 @@ static const struct snmp_mib snmp4_net_list[] = { SNMP_MIB_ITEM("TCPKeepAlive", LINUX_MIB_TCPKEEPALIVE), SNMP_MIB_ITEM("TCPMTUPFail", LINUX_MIB_TCPMTUPFAIL), SNMP_MIB_ITEM("TCPMTUPSuccess", LINUX_MIB_TCPMTUPSUCCESS), + SNMP_MIB_ITEM("TCPTSecrFail", LINUX_MIB_TCPTSECRFAIL), SNMP_MIB_SENTINEL };
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 1234244..e114777 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c@@ -5287,6 +5287,7 @@ syn_challenge: /* last step: ofo and not pure ack: check tsecr */ if (!tcp_validate_tsecr(sk, th)) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPTSECRFAIL); goto discard; }
--
2.7.3