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Date: Mon, 13 Jan 2003 03:11:50 +0100
To: linux-kernel@vger.kernel.org
Cc: davem@redhat.com
Subject: [PATCH] fix locking in /net/ipv4/tcp_ipv4.c
Message-ID: <20030113021150.GB4140@gagarin>
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From: Anders Gustafsson <andersg@0x63.nu>
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Hi,

the goto-discussion* reminded me of the locking for the seq_file reading in
/net/ipv4/tcp_ipv4.c. If only the header** is read tcp_listen_unlock() is
called without the lock taken. 

*  there are some lovely gotos in /net/ipv4/tcp_ipv4.c:listening_get_next
** (void *)1 is a marker for the header.

-- 
Anders Gustafsson - andersg@0x63.nu - http://0x63.nu/

You can import this changeset into BK by piping this whole message to:
'| bk receive [path to repository]' or apply the patch as usual.

===================================================================


ChangeSet@1.973, 2003-01-07 03:27:31+01:00, andersg@0x63.nu
  Don't tcp_listen_unlock unless it was locked.


 tcp_ipv4.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletion(-)


diff -Nru a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
--- a/net/ipv4/tcp_ipv4.c	Tue Jan  7 03:41:35 2003
+++ b/net/ipv4/tcp_ipv4.c	Tue Jan  7 03:41:35 2003
@@ -2412,7 +2412,8 @@
 			read_unlock_bh(&tp->syn_wait_lock);
 		}
 	case TCP_SEQ_STATE_LISTENING:
-		tcp_listen_unlock();
+		if (v != (void *)1)
+			tcp_listen_unlock();
 		break;
 	case TCP_SEQ_STATE_TIME_WAIT:
 	case TCP_SEQ_STATE_ESTABLISHED:

===================================================================


This BitKeeper patch contains the following changesets:
1.973
## Wrapped with gzip_uu ##


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`
end
-
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