netdev - [PATCH net-next] tcp: tcp_mtu

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:   Fri, 03 Nov 2017 06:09:17 -0700
From:   Eric Dumazet <eric.dumazet@...il.com>
To:     David Miller <davem@...emloft.net>
Cc:     netdev <netdev@...r.kernel.org>
Subject: [PATCH net-next] tcp: tcp_mtu_probing() cleanup

From: Eric Dumazet <edumazet@...gle.com>

Reduce one indentation level to make code more readable.
tcp_sync_mss() can be factorized.

Signed-off-by: Eric Dumazet <edumazet@...gle.com>
---
 net/ipv4/tcp_timer.c |   31 ++++++++++++++-----------------
 1 file changed, 14 insertions(+), 17 deletions(-)

diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 035a1ef1f2d8462c1d19f364b599ffac538ef688..16df6dd44b988a128d97df3a7953437499a216e8 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -107,26 +107,23 @@ static int tcp_orphan_retries(struct sock *sk, bool alive)
 
 static void tcp_mtu_probing(struct inet_connection_sock *icsk, struct sock *sk)
 {
-	struct net *net = sock_net(sk);
+	const struct net *net = sock_net(sk);
+	int mss;
 
 	/* Black hole detection */
-	if (net->ipv4.sysctl_tcp_mtu_probing) {
-		if (!icsk->icsk_mtup.enabled) {
-			icsk->icsk_mtup.enabled = 1;
-			icsk->icsk_mtup.probe_timestamp = tcp_jiffies32;
-			tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
-		} else {
-			struct net *net = sock_net(sk);
-			struct tcp_sock *tp = tcp_sk(sk);
-			int mss;
-
-			mss = tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_low) >> 1;
-			mss = min(net->ipv4.sysctl_tcp_base_mss, mss);
-			mss = max(mss, 68 - tp->tcp_header_len);
-			icsk->icsk_mtup.search_low = tcp_mss_to_mtu(sk, mss);
-			tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
-		}
+	if (!net->ipv4.sysctl_tcp_mtu_probing)
+		return;
+
+	if (!icsk->icsk_mtup.enabled) {
+		icsk->icsk_mtup.enabled = 1;
+		icsk->icsk_mtup.probe_timestamp = tcp_jiffies32;
+	} else {
+		mss = tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_low) >> 1;
+		mss = min(net->ipv4.sysctl_tcp_base_mss, mss);
+		mss = max(mss, 68 - tcp_sk(sk)->tcp_header_len);
+		icsk->icsk_mtup.search_low = tcp_mss_to_mtu(sk, mss);
 	}
+	tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 }