From 3aa030ab4a2db5deac9ae574e25b972b39d6c0d7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Jere=20Lepp=C3=A4nen?= Date: Tue, 21 Apr 2020 22:03:42 +0300 Subject: [PATCH] sctp: Fix SHUTDOWN CTSN Ack in the peer restart case MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit 12dfd78e3a74825e6f0bc8df7ef9f938fbc6bfe3 upstream. When starting shutdown in sctp_sf_do_dupcook_a(), get the value for SHUTDOWN Cumulative TSN Ack from the new association, which is reconstructed from the cookie, instead of the old association, which the peer doesn't have anymore. Otherwise the SHUTDOWN is either ignored or replied to with an ABORT by the peer because CTSN Ack doesn't match the peer's Initial TSN. Fixes: bdf6fa52f01b ("sctp: handle association restarts when the socket is closed.") Signed-off-by: Jere Leppänen Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sctp/sm_make_chunk.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index f67df16bd340..e698edd56bd5 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -858,7 +858,11 @@ struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc, struct sctp_chunk *retval; __u32 ctsn; - ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map); + if (chunk && chunk->asoc) + ctsn = sctp_tsnmap_get_ctsn(&chunk->asoc->peer.tsn_map); + else + ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map); + shut.cum_tsn_ack = htonl(ctsn); retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN, 0,