From: Wei Yongjun [ Upstream commit 77e2f14f71d68d05945f1d30ca55b5194d6ab1ce ] SCTP used ip6_xmit() to send fragments after received ICMP packet too big message. But while send packet used ip6_xmit, the skb->local_df is not initialized. So when skb if enter ip6_fragment(), the following code will discard the skb. ip6_fragment(...) { if (!skb->local_df) { ... return -EMSGSIZE; } ... } SCTP do the following step: 1. send packet ip6_xmit(skb, ipfragok=0) 2. received ICMP packet too big message 3. if PMTUD_ENABLE: ip6_xmit(skb, ipfragok=1) This patch fixed the problem by set local_df if ipfragok is true. Signed-off-by: Wei Yongjun Acked-by: Herbert Xu Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/ip6_output.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -231,6 +231,10 @@ int ip6_xmit(struct sock *sk, struct sk_ skb_reset_network_header(skb); hdr = ipv6_hdr(skb); + /* Allow local fragmentation. */ + if (ipfragok) + skb->local_df = 1; + /* * Fill in the IPv6 header */ -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/