From 28cd7752734563d5b0967b96a6bade7a1dc89c7f Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Sun, 29 Oct 2006 23:46:42 -0800 Subject: [PATCH] [SCTP]: Always linearise packet on input I was looking at a RHEL5 bug report involving Xen and SCTP (https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=212550). It turns out that SCTP wasn't written to handle skb fragments at all. The absence of any calls to skb_may_pull is testament to that. It just so happens that Xen creates fragmented packets more often than other scenarios (header & data split when going from domU to dom0). That's what caused this bug to show up. Until someone has the time sits down and audits the entire net/sctp directory, here is a conservative and safe solution that simply linearises all packets on input. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/sctp/input.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/sctp/input.c b/net/sctp/input.c index 64f630102532..99c0501ca513 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -135,6 +135,9 @@ int sctp_rcv(struct sk_buff *skb) SCTP_INC_STATS_BH(SCTP_MIB_INSCTPPACKS); + if (skb_linearize(skb)) + goto discard_it; + sh = (struct sctphdr *) skb->h.raw; /* Pull up the IP and SCTP headers. */ -- 2.20.1