netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Yan Zheng <yanzheng@21cn.com>
To: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, yoshfuji@linux-ipv6.org
Subject: Re: [PATCH][MCAST]IPv6: Check packet size when process Multicast Address and Source Specific Query
Date: Mon, 31 Oct 2005 20:09:45 +0800	[thread overview]
Message-ID: <43660989.2000100@21cn.com> (raw)
In-Reply-To: <20051031.142717.40152885.yoshfuji@linux-ipv6.org>

> 
> You cannot continue using mlh2, local copy of skb->h.raw
> after pskb_may_pull(). Please refresh it.
> 
> --yoshfuji
> 

My mistake. sorry.
I hope the new one is correct.

Regards
================================================================================
--- linux-2.6.14/net/ipv6/mcast.c	2005-10-30 23:09:33.000000000 +0800
+++ linux/net/ipv6/mcast.c	2005-10-31 14:16:19.000000000 +0800
@@ -1087,7 +1087,7 @@ static void mld_marksources(struct ifmca
 
 int igmp6_event_query(struct sk_buff *skb)
 {
-	struct mld2_query *mlh2 = (struct mld2_query *) skb->h.raw;
+	struct mld2_query *mlh2 = NULL;
 	struct ifmcaddr6 *ma;
 	struct in6_addr *group;
 	unsigned long max_delay;
@@ -1140,6 +1140,13 @@ int igmp6_event_query(struct sk_buff *sk
 		/* clear deleted report items */
 		mld_clear_delrec(idev);
 	} else if (len >= 28) {
+		int srcs_offset = sizeof(struct mld2_query) - 
+				  sizeof(struct icmp6hdr);
+		if (!pskb_may_pull(skb, srcs_offset)) {
+			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;
@@ -1156,7 +1163,15 @@ int igmp6_event_query(struct sk_buff *sk
 			return 0;
 		}
 		/* mark sources to include, if group & source-specific */
-		mark = mlh2->nsrcs != 0;
+		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;
+		}
 	} else {
 		in6_dev_put(idev);
 		return -EINVAL;

  reply	other threads:[~2005-10-31 12:09 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-10-31  5:20 [PATCH][MCAST]IPv6: Check packet size when process Multicast Address and Source Specific Query Yan Zheng
2005-10-31  5:27 ` YOSHIFUJI Hideaki / 吉藤英明
2005-10-31 12:09   ` Yan Zheng [this message]
2005-10-31 12:15     ` YOSHIFUJI Hideaki / 吉藤英明
2005-10-31 19:42 ` David Stevens
2005-11-01  4:20   ` Yan Zheng

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=43660989.2000100@21cn.com \
    --to=yanzheng@21cn.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=yoshfuji@linux-ipv6.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).