[DCCP]: DCCP's passive close needs to match TCP's half-close

This fixes a problem of integrating the new auxiliary states PASSIVE_1/2 with 
the
inet_xxx infrastructure. 

The problem appears on the listening side and is that
 * a Close may have been received on the socket while it is still in the accept 
queue
   of the master/listening socket;
 * hence when it is taken out of the queue by inet_accept(), the state of the 
socket
   is PASSIVE_1 (whose value is greater than all registered TCP states);
 * this triggers the following warning in inet_accept():
  
   Sep 10 16:52:27 kernel: KERNEL: \
        assertion ((1 << sk2->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | 
TCPF_CLOSE))\
        failed at /usr/src/main_davem-2.6/net/ipv4/af_inet.c (646)

The fix consists mapping PASSIVE_1 into TCPF_CLOSE_WAIT, which is possible since
there is no other mapping from a DCCP state into it. Incidentally, the 
`semantics'
of that state are also similar: in TCP's CLOSE_WAIT, a user confirmation to 
close
up the socket is needed - and the same (calling close/exit) situation arises 
here.

For a server deciding to hold TIMEWAIT state there is no such problem, since
DCCP_SOCKOPT_SERVER_TIMEWAIT can not be set on a listening socket, it is by 
default off
and not inherited to child sockets.

Lastly, for PASSIVE_2 the situation is simpler, since this is a client-only 
state. 

Signed-off-by: Gerrit Renker <[EMAIL PROTECTED]>
---
 include/linux/dccp.h |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/include/linux/dccp.h
+++ b/include/linux/dccp.h
@@ -249,14 +249,14 @@ enum dccp_state {
         * CLOSING, corresponds to (b) above) are used.
         */
        DCCP_CLOSEREQ   = TCP_FIN_WAIT1,
+       DCCP_PASSIVE_1  = TCP_CLOSE_WAIT,       /* any node receiving a Close */
        DCCP_CLOSING    = TCP_CLOSING,
        DCCP_TIME_WAIT  = TCP_TIME_WAIT,
        DCCP_CLOSED     = TCP_CLOSE,
        /* Everything below here is specific to DCCP only */
        DCCP_INTRINSICS = TCP_MAX_STATES,
        DCCP_PARTOPEN,
-       DCCP_PASSIVE_1,         /* any node receiving a Close  */
-       DCCP_PASSIVE_2,         /* client receiving a CloseReq */
+       DCCP_PASSIVE_2,                         /* client receiving CloseReq  */
        DCCP_MAX_STATES
 };
 
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