From 3bf5395102806e97f2c0e750c8adcc75816a3b42 Mon Sep 17 00:00:00 2001 From: Pau Espin Pedrol Date: Thu, 22 Sep 2022 16:10:34 +0200 Subject: [PATCH] hnbgw: Fix recent regression not closing conn upon rx of SCTP_SHUTDOWN_EVENT Before handling of OSMO_STREAM_SCTP_MSG_FLAGS_NOTIFICATION in recent commit (see Fixes: below), osmo_stream_srv_recv() and internal _sctp_recvmsg_wrapper() in libosmo-netif would return either -EAGAIN or 0 when an sctp notification was received from the kernel. After adding handling of OSMO_STREAM_SCTP_MSG_FLAGS_NOTIFICATION, the code paths for "rc == -EAGAIN" and "rc == 0" would not be executed anymore since the first branch takes preference in the if-else tree. For "rc == -EAGAIN" it's fine because the new branch superseeds what's done on the "rc == -EAGAIN" branch. However, for the "rc == 0", we forgot to actually destroy the connection. The "rc == 0" branch was basically reached when SCTP_SHUTDOWN_EVENT was received because osmo_stream_srv_recv() tried to resemble the interface of regular recv(); let's hence check for that explicitly and destroy the conn object (and the related hnb context in the process) when we receive that event. Fixes: 1de2091515530e531196ebca27b1445cecd1b88d Related: SYS#6113 Change-Id: I11b6af51a58dc250975a696b98d0c0c9ff3df9e0 --- src/osmo-hnbgw/hnbgw.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/src/osmo-hnbgw/hnbgw.c b/src/osmo-hnbgw/hnbgw.c index 124a647..6d75525 100644 --- a/src/osmo-hnbgw/hnbgw.c +++ b/src/osmo-hnbgw/hnbgw.c @@ -254,6 +254,7 @@ static int hnb_read_cb(struct osmo_stream_srv *conn) /* Notification received */ if (msgb_sctp_msg_flags(msg) & OSMO_STREAM_SCTP_MSG_FLAGS_NOTIFICATION) { union sctp_notification *notif = (union sctp_notification *)msgb_data(msg); + rc = 0; switch (notif->sn_header.sn_type) { case SCTP_ASSOC_CHANGE: switch (notif->sn_assoc_change.sac_state) { @@ -261,17 +262,23 @@ static int hnb_read_cb(struct osmo_stream_srv *conn) LOGHNB(hnb, DMAIN, LOGL_NOTICE, "HNB SCTP conn RESTARTed, marking as HNBAP-unregistered\n"); hnb->hnb_registered = false; break; + case SCTP_SHUTDOWN_EVENT: + LOGHNB(hnb, DMAIN, LOGL_NOTICE, + "sctp_recvmsg(%s) = SCTP_SHUTDOWN_EVENT, closing conn\n", + osmo_sock_get_name2(osmo_stream_srv_get_ofd(conn)->fd)); + osmo_stream_srv_destroy(conn); + rc = -1; + break; } break; } - msgb_free(msg); - return 0; + goto out; } else if (rc == -EAGAIN) { /* Older versions of osmo_stream_srv_recv() not supporting * msgb_sctp_msg_flags() may still return -EAGAIN when an sctp * notification is received. */ - msgb_free(msg); - return 0; + rc = 0; + goto out; } else if (rc < 0) { LOGHNB(hnb, DMAIN, LOGL_ERROR, "Error during sctp_recvmsg(%s)\n", osmo_sock_get_name2(osmo_stream_srv_get_ofd(conn)->fd));