Change in osmo-bsc[master]: Return -ENOTCONN from gsm0408_rcvmsg() if SCCP link is already closed.

[ipse]

ipse has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmo-bsc/+/18438 )


Change subject: Return -ENOTCONN from gsm0408_rcvmsg() if SCCP link is already closed.
......................................................................

Return -ENOTCONN from gsm0408_rcvmsg() if SCCP link is already closed.

Message processing here can fail for several reasons and we should be
able to differentiate them. If we need to discard the message because
of the FSM state, let's signal it to the caller differently than in
case of fatal errors. This would allow the caller to log the issue
differently.

Specifically, we observed, that we very often get Classmark Change
message from a phone right after the MSC has shut the SCCP connection
but before we close the lchan on the BTS.

This message flow hits this code path and we want to return -ENOTCONN
here so that the caller knows that this is not a message decoding
error or some other internal error.

Change-Id: I2d430ebc894a2345bebaa1841a75e94a3b45eae2
---
M src/osmo-bsc/gsm_04_08_rr.c
1 file changed, 1 insertion(+), 1 deletion(-)



  git pull ssh://gerrit.osmocom.org:29418/osmo-bsc refs/changes/38/18438/1

diff --git a/src/osmo-bsc/gsm_04_08_rr.c b/src/osmo-bsc/gsm_04_08_rr.c
index 586eeab..ca92c5b 100644
--- a/src/osmo-bsc/gsm_04_08_rr.c
+++ b/src/osmo-bsc/gsm_04_08_rr.c
@@ -1016,7 +1016,7 @@
 	lchan = msg->lchan;
 	if (!lchan_may_receive_data(lchan)) {
 		LOG_LCHAN(msg->lchan, LOGL_INFO, "Got data in non active state, discarding.\n");
-		return -1;
+		return -ENOTCONN;
 	}
 
 	if (lchan->conn) {

-- 
To view, visit https://gerrit.osmocom.org/c/osmo-bsc/+/18438
To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings

Gerrit-Project: osmo-bsc
Gerrit-Branch: master
Gerrit-Change-Id: I2d430ebc894a2345bebaa1841a75e94a3b45eae2
Gerrit-Change-Number: 18438
Gerrit-PatchSet: 1
Gerrit-Owner: ipse <Alexander.Chemeris at gmail.com>
Gerrit-MessageType: newchange
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osmocom.org/pipermail/gerrit-log/attachments/20200524/33702ced/attachment.htm>