pespin has submitted this change. ( https://gerrit.osmocom.org/c/libosmo-netif/+/29545 ) Change subject: stream: Return 0 when receiving sctp notification SCTP_COMM_LOST ...................................................................... stream: Return 0 when receiving sctp notification SCTP_COMM_LOST It was seen on a real pcap trace (sctp & gsmtap_log) that the Linux kernel stack may decide to kill the connection (sending an ABORT) if it fails to transmit some data after a while: ABORT Cause code: "Protocol violation (0x000d)", Cause Information: "Association exceeded its max_retrans count". When this occurs, the kernel sends the MSG_NOTIFICATION,SCTP_ASSOC_CHANGE,SCTP_COMM_LOST notification when reading from the socket with sctp_recvmsg(). This basically signals that the socket conn is dead, and subsequent writes to it will result in send() failures (and receive SCTP_SEND_FAILED notification upon follow up reads). It's important to notice that after those events, there's no other sort of different event like SHUTDOWN coming in, so that's the time at which we must tell the user to close the socket. Hence, let's signal the caller that the socket is dead by returning 0, to comply with usual recv() API. Related: SYS#6113 Change-Id: If94d44f25b76a96a5ea402fec9fc14c4e6296ba3 --- M src/stream.c 1 file changed, 2 insertions(+), 1 deletion(-) Approvals: pespin: Looks good to me, approved Jenkins Builder: Verified diff --git a/src/stream.c b/src/stream.c index 5e15142..38d24fe 100644 --- a/src/stream.c +++ b/src/stream.c @@ -1490,7 +1490,8 @@ break; case SCTP_COMM_LOST: LOGPC(DLINP, LOGL_DEBUG, " LOST\n"); - break; + /* Handle this like a regular disconnect */ + return 0; case SCTP_RESTART: LOGPC(DLINP, LOGL_DEBUG, " RESTART\n"); break; -- To view, visit https://gerrit.osmocom.org/c/libosmo-netif/+/29545 To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: libosmo-netif Gerrit-Branch: master Gerrit-Change-Id: If94d44f25b76a96a5ea402fec9fc14c4e6296ba3 Gerrit-Change-Number: 29545 Gerrit-PatchSet: 3 Gerrit-Owner: pespin <pespin@sysmocom.de> Gerrit-Reviewer: Jenkins Builder Gerrit-Reviewer: laforge <laforge@osmocom.org> Gerrit-Reviewer: neels <nhofmeyr@sysmocom.de> Gerrit-Reviewer: pespin <pespin@sysmocom.de> Gerrit-MessageType: merged