From 77b337196a9d87f3d6bb9b07c0436ecafbffda1e Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Fri, 28 Jan 2022 13:13:32 +0100 Subject: netfilter: conntrack: don't refresh sctp entries in closed state Vivek Thrivikraman reported: An SCTP server application which is accessed continuously by client application. When the session disconnects the client retries to establish a connection. After restart of SCTP server application the session is not established because of stale conntrack entry with connection state CLOSED as below. (removing this entry manually established new connection): sctp 9 CLOSED src=10.141.189.233 [..] [ASSURED] Just skip timeout update of closed entries, we don't want them to stay around forever. Reported-and-tested-by: Vivek Thrivikraman Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1579 Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_proto_sctp.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'net') diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c index 2394238d01c9..5a936334b517 100644 --- a/net/netfilter/nf_conntrack_proto_sctp.c +++ b/net/netfilter/nf_conntrack_proto_sctp.c @@ -489,6 +489,15 @@ int nf_conntrack_sctp_packet(struct nf_conn *ct, pr_debug("Setting vtag %x for dir %d\n", ih->init_tag, !dir); ct->proto.sctp.vtag[!dir] = ih->init_tag; + + /* don't renew timeout on init retransmit so + * port reuse by client or NAT middlebox cannot + * keep entry alive indefinitely (incl. nat info). + */ + if (new_state == SCTP_CONNTRACK_CLOSED && + old_state == SCTP_CONNTRACK_CLOSED && + nf_ct_is_confirmed(ct)) + ignore = true; } ct->proto.sctp.state = new_state; -- cgit v1.2.3