From 9af3912ec9e30509b76cb376abb65a4d8af27df3 Mon Sep 17 00:00:00 2001 From: John Heffner Date: Sun, 25 Mar 2007 23:32:29 -0700 Subject: [PATCH] [NET] Move DF check to ip_forward Do fragmentation check in ip_forward, similar to ipv6 forwarding. Signed-off-by: John Heffner Signed-off-by: David S. Miller --- net/ipv4/ip_forward.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c index 467ebedb99..61b30d1006 100644 --- a/net/ipv4/ip_forward.c +++ b/net/ipv4/ip_forward.c @@ -85,6 +85,14 @@ int ip_forward(struct sk_buff *skb) if (opt->is_strictroute && rt->rt_dst != rt->rt_gateway) goto sr_failed; + if (unlikely(skb->len > dst_mtu(&rt->u.dst) && + (ip_hdr(skb)->frag_off & htons(IP_DF))) && !skb->local_df) { + IP_INC_STATS(IPSTATS_MIB_FRAGFAILS); + icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, + htonl(dst_mtu(&rt->u.dst))); + goto drop; + } + /* We are about to mangle packet. Copy it! */ if (skb_cow(skb, LL_RESERVED_SPACE(rt->u.dst.dev)+rt->u.dst.header_len)) goto drop; -- 2.39.5