linux-kernel - [PATCH 4.1 091/202] netfilter: nftables: Do not run chains in the wrong network namespace

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 17 Oct 2015 18:57:54 -0700
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	stable@...r.kernel.org,
	"Eric W. Biederman" <ebiederm@...ssion.com>,
	Pablo Neira Ayuso <pablo@...filter.org>,
	"David S. Miller" <davem@...emloft.net>
Subject: [PATCH 4.1 091/202] netfilter: nftables: Do not run chains in the wrong network namespace

4.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: "Eric W. Biederman" <ebiederm@...ssion.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@...ssion.com>
Acked-by: Pablo Neira Ayuso <pablo@...filter.org>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.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);


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/