From 91bd6b1e030266cf87d3f567b49f0fa60a7318ba Mon Sep 17 00:00:00 2001 From: Wei Yongjun Date: Thu, 23 Oct 2008 00:59:52 -0700 Subject: [PATCH] sctp: Drop ICMP packet too big message with MTU larger than current PMTU If ICMP packet too big message is received with MTU larger than current PMTU, SCTP will still accept this ICMP message and sync the PMTU of assoc with the wrong MTU. Endpoing A Endpoint B (ESTABLISHED) (ESTABLISHED) ICMP ---------> (packet too big, MTU too larger) sync PMTU This patch fixed the problem by drop that ICMP message. Signed-off-by: Wei Yongjun Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller --- net/sctp/input.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/sctp/input.c b/net/sctp/input.c index a49fa80b57b..bf612d954d4 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -369,7 +369,7 @@ static void sctp_add_backlog(struct sock *sk, struct sk_buff *skb) void sctp_icmp_frag_needed(struct sock *sk, struct sctp_association *asoc, struct sctp_transport *t, __u32 pmtu) { - if (!t || (t->pathmtu == pmtu)) + if (!t || (t->pathmtu <= pmtu)) return; if (sock_owned_by_user(sk)) { -- 2.41.1