From: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Date: Sat, 18 Mar 2006 00:05:43 +0000 (-0800)
Subject: [NET]: Fix race condition in sk_wait_event().
X-Git-Tag: v2.6.16~8
X-Git-Url: http://www.pilppa.org/gitweb/gitweb.cgi?p=linux-2.6-omap-h63xx.git;a=commitdiff_plain;h=265a92856b17524c87da0258ac0d3cec80ae1d35

[NET]: Fix race condition in sk_wait_event().

It is broken, the condition is checked out of socket lock. It is
wonderful the bug survived for so long time.

[ This fixes bugzilla #6233:
  race condition in tcp_sendmsg when connection became established ]

Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/include/net/sock.h b/include/net/sock.h
index 30758035d61..f63d0d56712 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -478,9 +478,9 @@ static inline void sk_add_backlog(struct sock *sk, struct sk_buff *skb)
 	rc = __condition;					\
 	if (!rc) {						\
 		*(__timeo) = schedule_timeout(*(__timeo));	\
-		rc = __condition;				\
 	}							\
 	lock_sock(__sk);					\
+	rc = __condition;					\
 	rc;							\
 })