path: root/net/sctp
diff options
authorXin Long <lucien.xin@gmail.com>2019-01-22 02:42:41 +0800
committerDavid S. Miller <davem@davemloft.net>2019-01-24 18:13:57 -0800
commitecf938fe7d0088077ee1280419a2b3c5429b47c8 (patch)
treed95b6f275d7266f8b9cfd890dfe1d2072c905ef8 /net/sctp
parent4ff40b86262b73553ee47cc3784ce8ba0f220bd8 (diff)
sctp: set flow sport from saddr only when it's 0
Now sctp_transport_pmtu() passes transport->saddr into .get_dst() to set flow sport from 'saddr'. However, transport->saddr is set only when transport->dst exists in sctp_transport_route(). If sctp_transport_pmtu() is called without transport->saddr set, like when transport->dst doesn't exists, the flow sport will be set to 0 from transport->saddr, which will cause a wrong route to be got. Commit 6e91b578bf3f ("sctp: re-use sctp_transport_pmtu in sctp_transport_route") made the issue be triggered more easily since sctp_transport_pmtu() would be called in sctp_transport_route() after that. In gerneral, fl4->fl4_sport should always be set to htons(asoc->base.bind_addr.port), unless transport->asoc doesn't exist in sctp_v4/6_get_dst(), which is the case: sctp_ootb_pkt_new() -> sctp_transport_route() For that, we can simply handle it by setting flow sport from saddr only when it's 0 in sctp_v4/6_get_dst(). Fixes: 6e91b578bf3f ("sctp: re-use sctp_transport_pmtu in sctp_transport_route") Reported-by: Ying Xu <yinxu@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sctp')
2 files changed, 4 insertions, 2 deletions
diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index ed8e006dae85..6200cd2b4b99 100644
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -280,7 +280,8 @@ static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
if (saddr) {
fl6->saddr = saddr->v6.sin6_addr;
- fl6->fl6_sport = saddr->v6.sin6_port;
+ if (!fl6->fl6_sport)
+ fl6->fl6_sport = saddr->v6.sin6_port;
pr_debug("src=%pI6 - ", &fl6->saddr);
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index 4e0eeb113ef5..6abc8b274270 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -440,7 +440,8 @@ static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
if (saddr) {
fl4->saddr = saddr->v4.sin_addr.s_addr;
- fl4->fl4_sport = saddr->v4.sin_port;
+ if (!fl4->fl4_sport)
+ fl4->fl4_sport = saddr->v4.sin_port;
pr_debug("%s: dst:%pI4, src:%pI4 - ", __func__, &fl4->daddr,