From: Florian Westphal fw@strlen.de
[ Upstream commit 77b337196a9d87f3d6bb9b07c0436ecafbffda1e ]
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 vivek.thrivikraman@est.tech Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1579 Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/netfilter/nf_conntrack_proto_sctp.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c index a937d4f75613f..8cb62805fd684 100644 --- a/net/netfilter/nf_conntrack_proto_sctp.c +++ b/net/netfilter/nf_conntrack_proto_sctp.c @@ -394,6 +394,15 @@ static int 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;