From patchwork Thu Jan 24 02:44:34 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [v2] sctp: set association state to established in dupcook_a handler Date: Wed, 23 Jan 2013 16:44:34 -0000 From: Xufeng Zhang X-Patchwork-Id: 215102 Message-Id: <1358995474-28369-1-git-send-email-xufengzhang.main@gmail.com> To: , , Cc: , , From: Xufeng Zhang While sctp handling a duplicate COOKIE-ECHO and the action is 'Association restart', sctp_sf_do_dupcook_a() will processing the unexpected COOKIE-ECHO for peer restart, but it does not set the association state to SCTP_STATE_ESTABLISHED, so the association could stuck in SCTP_STATE_SHUTDOWN_PENDING state forever. This violates the sctp specification: RFC 4960 5.2.4. Handle a COOKIE ECHO when a TCB Exists Action A) In this case, the peer may have restarted. ..... After this, the endpoint shall enter the ESTABLISHED state. To resolve this problem, adding a SCTP_CMD_NEW_STATE cmd to the command list before SCTP_CMD_REPLY cmd, this will set the restart association to SCTP_STATE_ESTABLISHED state properly and also avoid I-bit being set in the DATA chunk header when COOKIE_ACK is bundled with DATA chunks. Signed-off-by: Xufeng Zhang Acked-by: Neil Horman Acked-by: Vlad Yasevich --- v2: - Put the SCTP_CMD_NEW_STATE command before SCTP_CMD_REPLY and after SCTP_CMD_EVENT_ULP suggested by Vlad and Neil - Improve the last paragraph of the commit header net/sctp/sm_statefuns.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index 618ec7e..5131fcf 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -1779,8 +1779,10 @@ static sctp_disposition_t sctp_sf_do_dupcook_a(struct net *net, /* Update the content of current association. */ sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); - sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); + sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, + SCTP_STATE(SCTP_STATE_ESTABLISHED)); + sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); return SCTP_DISPOSITION_CONSUME; nomem_ev: