From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Sun, 4 Jan 2015 14:20:29 +0000 (+0100)
Subject: netfilter: nfnetlink: validate nfnetlink header from batch
X-Git-Tag: v3.16.35~3022
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=d922a1cee45e9ee78fd973ffef2132a9bda94a5d;p=thirdparty%2Fkernel%2Fstable.git

netfilter: nfnetlink: validate nfnetlink header from batch

commit 9ea2aa8b7dba9e99544c4187cc298face254569f upstream.

Make sure there is enough room for the nfnetlink header in the
netlink messages that are part of the batch. There is a similar
check in netlink_rcv_skb().

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---

diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index c138b8fbe280a..6ae88ace21cbc 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -273,7 +273,8 @@ replay:
 		nlh = nlmsg_hdr(skb);
 		err = 0;
 
-		if (nlh->nlmsg_len < NLMSG_HDRLEN) {
+		if (nlmsg_len(nlh) < sizeof(struct nfgenmsg) ||
+		    skb->len < nlh->nlmsg_len) {
 			err = -EINVAL;
 			goto ack;
 		}