[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 <gerrit@xxxxxxxxxxxxxx>
---
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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