netdev - [PATCH v2 1/2] tcp: refactor 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-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 20 Jan 2012 13:08:02 -0500
From:	Satoru Moriya <satoru.moriya@....com>
To:	"netdev@...r.kernel.org" <netdev@...r.kernel.org>
CC:	"davem@...emloft.net" <davem@...emloft.net>,
	"nhorman@...driver.com" <nhorman@...driver.com>,
	"tgraf@...radead.org" <tgraf@...radead.org>,
	Stephen Hemminger <stephen.hemminger@...tta.com>,
	Hagen Paul Pfeifer <hagen@...u.net>,
	"eric.dumazet@...il.com" <eric.dumazet@...il.com>,
	Seiji Aguchi <seiji.aguchi@....com>
Subject: [PATCH v2 1/2] tcp: refactor tcp_retransmit_skb() for a single
 return point

This is just a cleanup patch for making easy to hook return value
with a tracepoint.

Signed-off-by: Satoru Moriya <satoru.moriya@....com>
---
 net/ipv4/tcp_output.c |   31 +++++++++++++++++++++----------
 1 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 8c8de27..7bd23a8 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -2092,18 +2092,24 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
 	 * copying overhead: fragmentation, tunneling, mangling etc.
 	 */
 	if (atomic_read(&sk->sk_wmem_alloc) >
-	    min(sk->sk_wmem_queued + (sk->sk_wmem_queued >> 2), sk->sk_sndbuf))
-		return -EAGAIN;
+	    min(sk->sk_wmem_queued + (sk->sk_wmem_queued >> 2), sk->sk_sndbuf)) {
+		err = -EAGAIN;
+		goto out;
+	}
 
 	if (before(TCP_SKB_CB(skb)->seq, tp->snd_una)) {
 		if (before(TCP_SKB_CB(skb)->end_seq, tp->snd_una))
 			BUG();
-		if (tcp_trim_head(sk, skb, tp->snd_una - TCP_SKB_CB(skb)->seq))
-			return -ENOMEM;
+		if (tcp_trim_head(sk, skb, tp->snd_una - TCP_SKB_CB(skb)->seq)) {
+			err = -ENOMEM;
+			goto out;
+		}
 	}
 
-	if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk))
-		return -EHOSTUNREACH; /* Routing failure or similar. */
+	if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk)) {
+		err = -EHOSTUNREACH; /* Routing failure or similar. */
+		goto out;
+	}
 
 	cur_mss = tcp_current_mss(sk);
 
@@ -2113,12 +2119,16 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
 	 * our retransmit serves as a zero window probe.
 	 */
 	if (!before(TCP_SKB_CB(skb)->seq, tcp_wnd_end(tp)) &&
-	    TCP_SKB_CB(skb)->seq != tp->snd_una)
-		return -EAGAIN;
+	    TCP_SKB_CB(skb)->seq != tp->snd_una) {
+		err = -EAGAIN;
+		goto out;
+	}
 
 	if (skb->len > cur_mss) {
-		if (tcp_fragment(sk, skb, cur_mss, cur_mss))
-			return -ENOMEM; /* We'll try again later. */
+		if (tcp_fragment(sk, skb, cur_mss, cur_mss)) {
+			err = -ENOMEM; /* We'll try again later. */
+			goto out;
+		}
 	} else {
 		int oldpcount = tcp_skb_pcount(skb);
 
@@ -2188,6 +2198,7 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
 		 */
 		TCP_SKB_CB(skb)->ack_seq = tp->snd_nxt;
 	}
+out:
 	return err;
 }
 
-- 
1.7.6.4

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html