Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for you net tree,
they are:

1) There was a race condition between parallel save/swap and delete,
   which resulted a kernel crash due to the increase ref for save, swap,
   wrong ref decrease operations. Reported and fixed by Vishwanath Pai.

2) OVS should call into CT NAT for packets of new expected connections only
   when the conntrack state is persisted with the 'commit' option to the
   OVS CT action. From Jarno Rajahalme.

3) Resolve kconfig dependencies with new OVS NAT support. From Arnd Bergmann.

4) Early validation of entry->target_offset to make sure it doesn't take us
   out from the blob, from Florian Westphal.

5) Again early validation of entry->next_offset to make sure it doesn't take
   out from the blob, also from Florian.

6) Check that entry->target_offset is always of of sizeof(struct xt_entry)
   for unconditional entries, when checking both from check_underflow()
   and when checking for loops in mark_source_chains(), again from
   Florian.

7) Fix inconsistent behaviour in nfnetlink_queue when
   NFQA_CFG_F_FAIL_OPEN is set and netlink_unicast() fails due to buffer
   overrun, we have to reinject the packet as the user expects.

8) Enforce nul-terminated table names from getsockopt GET_ENTRIES
   requests.

9) Don't assume skb->sk is set from nft_bridge_reject and synproxy,
   this fixes a recent update of the code to namespaceify
   ip_default_ttl, patch from Liping Zhang.

This batch comes with four patches to validate x_tables blobs coming
from userspace. CONFIG_USERNS exposes the x_tables interface to
unpriviledged users and to be honest this interface never received the
attention for this move away from the CAP_NET_ADMIN domain. Florian is
working on another round with more patches with more sanity checks, so
expect a bit more Netfilter fixes in this development cycle than usual.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 14 insertions, 10 deletions

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 67b2e27999aa..8570bc7744c2 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1521,6 +1521,8 @@ static int do_ebt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
 	if (copy_from_user(&tmp, user, sizeof(tmp)))
 		return -EFAULT;
 
+	tmp.name[sizeof(tmp.name) - 1] = '\0';
+
 	t = find_table_lock(net, tmp.name, &ret, &ebt_mutex);
 	if (!t)
 		return ret;
@@ -2332,6 +2334,8 @@ static int compat_do_ebt_get_ctl(struct sock *sk, int cmd,
 	if (copy_from_user(&tmp, user, sizeof(tmp)))
 		return -EFAULT;
 
+	tmp.name[sizeof(tmp.name) - 1] = '\0';
+
 	t = find_table_lock(net, tmp.name, &ret, &ebt_mutex);
 	if (!t)
 		return ret;
diff --git a/net/bridge/netfilter/nft_reject_bridge.c b/net/bridge/netfilter/nft_reject_bridge.c
index adc8d7221dbb..77f7e7a9ebe1 100644
--- a/net/bridge/netfilter/nft_reject_bridge.c
+++ b/net/bridge/netfilter/nft_reject_bridge.c
@@ -40,7 +40,8 @@ static void nft_reject_br_push_etherhdr(struct sk_buff *oldskb,
 /* We cannot use oldskb->dev, it can be either bridge device (NF_BRIDGE INPUT)
  * or the bridge port (NF_BRIDGE PREROUTING).
  */
-static void nft_reject_br_send_v4_tcp_reset(struct sk_buff *oldskb,
+static void nft_reject_br_send_v4_tcp_reset(struct net *net,
+					    struct sk_buff *oldskb,
 					    const struct net_device *dev,
 					    int hook)
 {
@@ -48,7 +49,6 @@ static void nft_reject_br_send_v4_tcp_reset(struct sk_buff *oldskb,
 	struct iphdr *niph;
 	const struct tcphdr *oth;
 	struct tcphdr _oth;
-	struct net *net = sock_net(oldskb->sk);
 
 	if (!nft_bridge_iphdr_validate(oldskb))
 		return;
@@ -75,7 +75,8 @@ static void nft_reject_br_send_v4_tcp_reset(struct sk_buff *oldskb,
 	br_deliver(br_port_get_rcu(dev), nskb);
 }
 
-static void nft_reject_br_send_v4_unreach(struct sk_buff *oldskb,
+static void nft_reject_br_send_v4_unreach(struct net *net,
+					  struct sk_buff *oldskb,
 					  const struct net_device *dev,
 					  int hook, u8 code)
 {
@@ -86,7 +87,6 @@ static void nft_reject_br_send_v4_unreach(struct sk_buff *oldskb,
 	void *payload;
 	__wsum csum;
 	u8 proto;
-	struct net *net = sock_net(oldskb->sk);
 
 	if (oldskb->csum_bad || !nft_bridge_iphdr_validate(oldskb))
 		return;
@@ -273,17 +273,17 @@ static void nft_reject_bridge_eval(const struct nft_expr *expr,
 	case htons(ETH_P_IP):
 		switch (priv->type) {
 		case NFT_REJECT_ICMP_UNREACH:
-			nft_reject_br_send_v4_unreach(pkt->skb, pkt->in,
-						      pkt->hook,
+			nft_reject_br_send_v4_unreach(pkt->net, pkt->skb,
+						      pkt->in, pkt->hook,
 						      priv->icmp_code);
 			break;
 		case NFT_REJECT_TCP_RST:
-			nft_reject_br_send_v4_tcp_reset(pkt->skb, pkt->in,
-							pkt->hook);
+			nft_reject_br_send_v4_tcp_reset(pkt->net, pkt->skb,
+							pkt->in, pkt->hook);
 			break;
 		case NFT_REJECT_ICMPX_UNREACH:
-			nft_reject_br_send_v4_unreach(pkt->skb, pkt->in,
-						      pkt->hook,
+			nft_reject_br_send_v4_unreach(pkt->net, pkt->skb,
+						      pkt->in, pkt->hook,
 						      nft_reject_icmp_code(priv->icmp_code));
 			break;
 		}