On Thu, Jan 24, 2013 at 10:44:34AM +0800, xufengzhang.main@xxxxxxxxx wrote: > From: Xufeng Zhang <xufeng.zhang@xxxxxxxxxxxxx> > > 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 <xufeng.zhang@xxxxxxxxxxxxx> > --- > 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: > -- > 1.7.0.2 > > Acked-by: Neil Horman <nhorman@xxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
