dccp: Add check for truncated ICMPv6 DCCP error packets

This patch adds a minimum-length check for ICMPv6 packets, as per the previous
patch for ICMPv4 payloads.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>

1 files changed, 6 insertions, 0 deletions

diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 25826b1bf68..5e1ee0da2c4 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -96,6 +96,12 @@ static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
         __u64 seq;
         struct net *net = dev_net(skb->dev);
 
+        if (skb->len < offset + sizeof(*dh) ||
+            skb->len < offset + __dccp_basic_hdr_len(dh)) {
+                ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
+                return;
+        }
+
         sk = inet6_lookup(net, &dccp_hashinfo,
                         &hdr->daddr, dh->dccph_dport,
                         &hdr->saddr, dh->dccph_sport, inet6_iif(skb));