Subject: [PATCH net-next] ndisc: Check NS message length before access.

From: YOSHIFUJI Hideaki <[email-masked]>
Date: Fri, 18 Jan 2013 21:05:03 +0900

Check message length before accessing "target" field,
as we do for other types.

Signed-off-by: YOSHIFUJI Hideaki <[email-masked]>
---
 net/ipv6/ndisc.c |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 429622d..350f860 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -671,6 +671,11 @@ static void ndisc_recv_ns(struct sk_buff *skb)
 	bool inc;
 	int is_router = -1;
 
+	if (skb->len < sizeof(struct nd_msg)) {
+		ND_PRINTK(2, warn, "NS: packet too short\n");
+		return;
+	}
+
 	if (ipv6_addr_is_multicast(&msg->target)) {
 		ND_PRINTK(2, warn, "NS: multicast target address\n");
 		return;
-- 
1.7.9.5