From b800c3b966bcf004bd8592293a49ed5cb7ea67a9 Mon Sep 17 00:00:00 2001 From: Hannes Frederic Sowa Date: Tue, 27 Aug 2013 01:36:51 +0200 Subject: ipv6: drop fragmented ndisc packets by default (RFC 6980) This patch implements RFC6980: Drop fragmented ndisc packets by default. If a fragmented ndisc packet is received the user is informed that it is possible to disable the check. Cc: Fernando Gont Cc: YOSHIFUJI Hideaki Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller --- net/ipv6/ndisc.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'net/ipv6/ndisc.c') diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index 04d31c2fbef1..41720feeaa64 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -1519,10 +1519,27 @@ static void pndisc_redo(struct sk_buff *skb) kfree_skb(skb); } +static bool ndisc_suppress_frag_ndisc(struct sk_buff *skb) +{ + struct inet6_dev *idev = __in6_dev_get(skb->dev); + + if (!idev) + return true; + if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED && + idev->cnf.suppress_frag_ndisc) { + net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n"); + return true; + } + return false; +} + int ndisc_rcv(struct sk_buff *skb) { struct nd_msg *msg; + if (ndisc_suppress_frag_ndisc(skb)) + return 0; + if (skb_linearize(skb)) return 0; -- cgit v1.2.3