[PATCH] sk_reuse fixes

[PATCH] sk_reuse fixes

[Ilya Pashkovsky]

This fixes sk_reuse checks:
1) allow outgoing connections AND one listening socket bound to same
source port.
2) remove > 1 check of a boolean variable

http://puding.mine.nu/patches/patch-reuse-bool

--- linux/net/ipv4/tcp_ipv4.c.orig	2004-12-07 14:54:12.597084704 +0200
+++ linux/net/ipv4/tcp_ipv4.c	2004-12-08 14:47:27.792827816 +0200
@@ -50,6 +50,8 @@
  *	YOSHIFUJI Hideaki @USAGI and:	Support IPV6_V6ONLY socket option, which
  *	Alexey Kuznetsov		allow both IPv4 and IPv6 sockets to bind
  *					a single port at the same time.
+ *	Ilya Pashkovsky		:	fix TCP_LISTEN check on reuse
+ *					remove (sk_reuse > 1) check in get_port
  */
 
 #include <linux/config.h>
@@ -184,7 +186,8 @@ static inline int tcp_bind_conflict(stru
 	const u32 sk_rcv_saddr = tcp_v4_rcv_saddr(sk);
 	struct sock *sk2;
 	struct hlist_node *node;
-	int reuse = sk->sk_reuse;
+	unsigned char reuse = sk->sk_reuse;
+	unsigned char state = sk->sk_state;
 
 	sk_for_each_bound(sk2, node, &tb->owners) {
 		if (sk != sk2 &&
@@ -193,7 +196,7 @@ static inline int tcp_bind_conflict(stru
 		     !sk2->sk_bound_dev_if ||
 		     sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
 			if (!reuse || !sk2->sk_reuse ||
-			    sk2->sk_state == TCP_LISTEN) {
+			    (state == TCP_LISTEN && sk2->sk_state == TCP_LISTEN)) {
 				const u32 sk2_rcv_saddr = tcp_v4_rcv_saddr(sk2);
 				if (!sk2_rcv_saddr || !sk_rcv_saddr ||
 				    sk2_rcv_saddr == sk_rcv_saddr)
@@ -259,8 +262,14 @@ static int tcp_v4_get_port(struct sock *
 	goto tb_not_found;
 tb_found:
 	if (!hlist_empty(&tb->owners)) {
-		if (sk->sk_reuse > 1)
-			goto success;
+
+		/* 
+		 * sk_reuse is boolean
+		 *
+		 *if (sk->sk_reuse > 1)
+		 *	goto success;
+		 */
+
 		if (tb->fastreuse > 0 &&
 		    sk->sk_reuse && sk->sk_state != TCP_LISTEN) {
 			goto success;

Re: [PATCH] sk_reuse fixes

[YOSHIFUJI Hideaki / 吉藤英明]

Hello.

In article <fcb9aa29041208045671633835@mail.gmail.com> (at Wed, 8 Dec 2004 14:56:31 +0200), Ilya Pashkovsky <ilya.pashkovsky@gmail.com> says:

> This fixes sk_reuse checks:
> 1) allow outgoing connections AND one listening socket bound to same
> source port.
> 2) remove > 1 check of a boolean variable

Two comments:

1. This (boolean variable) is not the case on Linux.
   Behavior is differentiated with sk_reuse > 1.
2. Please provide tcp_ipv6 part as well.

--yoshfuji