Subject: [PATCH][MCAST]Check packet size when process Multicast Address and Source Specific Query

From: Yan Zheng <[email-masked]>
Date: Wed, 09 Nov 2005 20:35:26 +0800

The patch changes the old one to equivalent code in IGMPv3 as David Stevens's suggestion
http://lkml.org/lkml/2005/10/31/221

Regards

Signed-off-by: Yan Zheng<[email-masked]>

Index:net/ipv6/mcast.c
============================================================== 

--- linux-2.6.14/net/ipv6/mcast.c	2005-11-09 16:00:48.000000000 +0800
+++ linux/net/ipv6/mcast.c	2005-11-09 16:20:03.000000000 +0800
@@ -1149,6 +1149,14 @@ int igmp6_event_query(struct sk_buff *sk
 			return -EINVAL;
 		}
 		mlh2 = (struct mld2_query *) skb->h.raw;
+		if (mlh2->nsrcs != 0) {
+			if (!pskb_may_pull(skb, srcs_offset +
+				mlh2->nsrcs * sizeof(struct in6_addr))) {
+				in6_dev_put(idev);
+				return -EINVAL;
+			}
+			mlh2 = (struct mld2_query *) skb->h.raw;
+		}
 		max_delay = (MLDV2_MRC(ntohs(mlh2->mrc))*HZ)/1000;
 		if (!max_delay)
 			max_delay = 1;
@@ -1165,15 +1173,7 @@ int igmp6_event_query(struct sk_buff *sk
 			return 0;
 		}
 		/* mark sources to include, if group & source-specific */
-		if (mlh2->nsrcs != 0) {
-			if (!pskb_may_pull(skb, srcs_offset + 
-				mlh2->nsrcs * sizeof(struct in6_addr))) {
-				in6_dev_put(idev);
-				return -EINVAL;
-			}
-			mlh2 = (struct mld2_query *) skb->h.raw;
-			mark = 1;
-		}
+		mark = mlh2->nsrcs != 0;
 	} else {
 		in6_dev_put(idev);
 		return -EINVAL;