[PATCH 3.4 073/107] sctp: donot reset the overall_error_count in SHUTDOWN_RECEIVE state

lizf
2016-03-16T08:11:58Z

From: lucien <lucien.xin@gmail.com>

3.4.111-rc1 review patch. If anyone has any objections, please let me know.

------------------

commit f648f807f61e64d247d26611e34cc97e4ed03401 upstream.

Commit f8d960524328 ("sctp: Enforce retransmission limit during shutdown")
fixed a problem with excessive retransmissions in the SHUTDOWN_PENDING by not
resetting the association overall_error_count. This allowed the association
to better enforce assoc.max_retrans limit.

However, the same issue still exists when the association is in SHUTDOWN_RECEIVED
state. In this state, HB-ACKs will continue to reset the overall_error_count
for the association would extend the lifetime of association unnecessarily.

This patch solves this by resetting the overall_error_count whenever the current
state is small then SCTP_STATE_SHUTDOWN_PENDING. As a small side-effect, we
end up also handling SCTP_STATE_SHUTDOWN_ACK_SENT and SCTP_STATE_SHUTDOWN_SENT
states, but they are not really impacted because we disable Heartbeats in those
states.

Fixes: Commit f8d960524328 ("sctp: Enforce retransmission limit during shutdown")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Zefan Li <lizefan@huawei.com>
---
net/sctp/sm_sideeffect.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
index 1ff51c9..5fa033a 100644
--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -682,7 +682,7 @@ static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
* outstanding data and rely on the retransmission limit be reached
* to shutdown the association.
*/
- if (t->asoc->state != SCTP_STATE_SHUTDOWN_PENDING)
+ if (t->asoc->state < SCTP_STATE_SHUTDOWN_PENDING)
t->asoc->overall_error_count = 0;

/* Clear the hb_sent flag to signal that we had a good
--
1.9.1