Patch "netfilter: nftables: Do not run chains in the wrong network namespace" has been added to the 4.1-stable tree

Patch "netfilter: nftables: Do not run chains in the wrong network namespace" has been added to the 4.1-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    netfilter: nftables: Do not run chains in the wrong network namespace

to the 4.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     netfilter-nftables-do-not-run-chains-in-the-wrong-network-namespace.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From fdab6a4cbd8933092155449ca7253eba973ada14 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Fri, 19 Jun 2015 10:41:21 -0500
Subject: netfilter: nftables: Do not run chains in the wrong network namespace

From: "Eric W. Biederman" <ebiederm@xmission.com>

commit fdab6a4cbd8933092155449ca7253eba973ada14 upstream.

Currenlty nf_tables chains added in one network namespace are being
run in all network namespace.  The issues are myriad with the simplest
being an unprivileged user can cause any network packets to be dropped.

Address this by simply not running nf_tables chains in the wrong
network namespace.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/netfilter/nf_tables_core.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/net/netfilter/nf_tables_core.c
+++ b/net/netfilter/nf_tables_core.c
@@ -114,7 +114,8 @@ unsigned int
 nft_do_chain(struct nft_pktinfo *pkt, const struct nf_hook_ops *ops)
 {
 	const struct nft_chain *chain = ops->priv, *basechain = chain;
-	const struct net *net = read_pnet(&nft_base_chain(basechain)->pnet);
+	const struct net *chain_net = read_pnet(&nft_base_chain(basechain)->pnet);
+	const struct net *net = dev_net(pkt->in ? pkt->in : pkt->out);
 	const struct nft_rule *rule;
 	const struct nft_expr *expr, *last;
 	struct nft_regs regs;
@@ -124,6 +125,10 @@ nft_do_chain(struct nft_pktinfo *pkt, co
 	int rulenum;
 	unsigned int gencursor = nft_genmask_cur(net);
 
+	/* Ignore chains that are not for the current network namespace */
+	if (!net_eq(net, chain_net))
+		return NF_ACCEPT;
+
 do_chain:
 	rulenum = 0;
 	rule = list_entry(&chain->rules, struct nft_rule, list);


Patches currently in stable-queue which might be from ebiederm@xmission.com are

queue-4.1/netfilter-nftables-do-not-run-chains-in-the-wrong-network-namespace.patch
queue-4.1/netfilter-nf_qeueue-drop-queue-entries-on-nf_unregister_hook.patch