Commit 442fad94 authored Feb 11, 2013 by Florian Westphal Committed by Pablo Neira Ayuso Feb 12, 2013

netfilter: ctnetlink: don't permit ct creation with random tuple



Userspace can cause kernel panic by not specifying orig/reply
tuple: kernel will create a tuple with random stack values.

Problem is that tuple.dst.dir will be random, too, which
causes nf_ct_tuplehash_to_ctrack() to return garbage.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@gnumonks.org>

parent 547b4e71

net/netfilter/nf_conntrack_netlink.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -1705,6 +1705,9 @@ ctnetlink_new_conntrack(struct sock ctnl, struct sk_buff skb,
		if (nlh->nlmsg_flags & NLM_F_CREATE) {
		enum ip_conntrack_events events;

		if (!cda[CTA_TUPLE_ORIG] \|\| !cda[CTA_TUPLE_REPLY])
		return -EINVAL;

		ct = ctnetlink_create_conntrack(net, zone, cda, &otuple,
		&rtuple, u3);
		if (IS_ERR(ct))