netfilter: check if the socket netns is correct.

Netfilter assumes that if the socket is present in the skb, then
it can be used because that reference is cleaned up while the skb
is crossing netns.

We want to change that to preserve the socket reference in a future
patch, so this is a preparation updating netfilter to check if the
socket netns matches before use it.

Signed-off-by: Flavio Leitner <fbl@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/netfilter/nf_log.h b/include/net/netfilter/nf_log.h
index e811ac0..0d39208 100644 (file)
--- a/include/net/netfilter/nf_log.h
+++ b/include/net/netfilter/nf_log.h
@@ -106,7 +106,8 @@ int nf_log_dump_udp_header(struct nf_log_buf *m, const struct sk_buff *skb,
 int nf_log_dump_tcp_header(struct nf_log_buf *m, const struct sk_buff *skb,
                           u8 proto, int fragment, unsigned int offset,
                           unsigned int logflags);
-void nf_log_dump_sk_uid_gid(struct nf_log_buf *m, struct sock *sk);
+void nf_log_dump_sk_uid_gid(struct net *net, struct nf_log_buf *m,
+                           struct sock *sk);
 void nf_log_dump_packet_common(struct nf_log_buf *m, u_int8_t pf,
                               unsigned int hooknum, const struct sk_buff *skb,
                               const struct net_device *in,

diff --git a/net/ipv4/netfilter/nf_log_ipv4.c b/net/ipv4/netfilter/nf_log_ipv4.c
index 4388de0..1e6f28c 100644 (file)
--- a/net/ipv4/netfilter/nf_log_ipv4.c
+++ b/net/ipv4/netfilter/nf_log_ipv4.c
@@ -35,7 +35,7 @@ static const struct nf_loginfo default_loginfo = {
 };
 
 /* One level of recursion won't kill us */
-static void dump_ipv4_packet(struct nf_log_buf *m,
+static void dump_ipv4_packet(struct net *net, struct nf_log_buf *m,
                             const struct nf_loginfo *info,
                             const struct sk_buff *skb, unsigned int iphoff)
 {
@@ -183,7 +183,7 @@ static void dump_ipv4_packet(struct nf_log_buf *m,
                        /* Max length: 3+maxlen */
                        if (!iphoff) { /* Only recurse once. */
                                nf_log_buf_add(m, "[");
-                               dump_ipv4_packet(m, info, skb,
+                               dump_ipv4_packet(net, m, info, skb,
                                            iphoff + ih->ihl*4+sizeof(_icmph));
                                nf_log_buf_add(m, "] ");
                        }
@@ -251,7 +251,7 @@ static void dump_ipv4_packet(struct nf_log_buf *m,
 
        /* Max length: 15 "UID=4294967295 " */
        if ((logflags & NF_LOG_UID) && !iphoff)
-               nf_log_dump_sk_uid_gid(m, skb->sk);
+               nf_log_dump_sk_uid_gid(net, m, skb->sk);
 
        /* Max length: 16 "MARK=0xFFFFFFFF " */
        if (!iphoff && skb->mark)
@@ -333,7 +333,7 @@ static void nf_log_ip_packet(struct net *net, u_int8_t pf,
        if (in != NULL)
                dump_ipv4_mac_header(m, loginfo, skb);
 
-       dump_ipv4_packet(m, loginfo, skb, 0);
+       dump_ipv4_packet(net, m, loginfo, skb, 0);
 
        nf_log_buf_close(m);
 }

diff --git a/net/ipv6/netfilter/nf_log_ipv6.c b/net/ipv6/netfilter/nf_log_ipv6.c
index b397a8f..c6bf580 100644 (file)
--- a/net/ipv6/netfilter/nf_log_ipv6.c
+++ b/net/ipv6/netfilter/nf_log_ipv6.c
@@ -36,7 +36,7 @@ static const struct nf_loginfo default_loginfo = {
 };
 
 /* One level of recursion won't kill us */
-static void dump_ipv6_packet(struct nf_log_buf *m,
+static void dump_ipv6_packet(struct net *net, struct nf_log_buf *m,
                             const struct nf_loginfo *info,
                             const struct sk_buff *skb, unsigned int ip6hoff,
                             int recurse)
@@ -258,7 +258,7 @@ static void dump_ipv6_packet(struct nf_log_buf *m,
                        /* Max length: 3+maxlen */
                        if (recurse) {
                                nf_log_buf_add(m, "[");
-                               dump_ipv6_packet(m, info, skb,
+                               dump_ipv6_packet(net, m, info, skb,
                                                 ptr + sizeof(_icmp6h), 0);
                                nf_log_buf_add(m, "] ");
                        }
@@ -278,7 +278,7 @@ static void dump_ipv6_packet(struct nf_log_buf *m,
 
        /* Max length: 15 "UID=4294967295 " */
        if ((logflags & NF_LOG_UID) && recurse)
-               nf_log_dump_sk_uid_gid(m, skb->sk);
+               nf_log_dump_sk_uid_gid(net, m, skb->sk);
 
        /* Max length: 16 "MARK=0xFFFFFFFF " */
        if (recurse && skb->mark)
@@ -365,7 +365,7 @@ static void nf_log_ip6_packet(struct net *net, u_int8_t pf,
        if (in != NULL)
                dump_ipv6_mac_header(m, loginfo, skb);
 
-       dump_ipv6_packet(m, loginfo, skb, skb_network_offset(skb), 1);
+       dump_ipv6_packet(net, m, loginfo, skb, skb_network_offset(skb), 1);
 
        nf_log_buf_close(m);
 }

diff --git a/net/netfilter/nf_conntrack_broadcast.c b/net/netfilter/nf_conntrack_broadcast.c
index a1086bd..5423b19 100644 (file)
--- a/net/netfilter/nf_conntrack_broadcast.c
+++ b/net/netfilter/nf_conntrack_broadcast.c
@@ -32,7 +32,7 @@ int nf_conntrack_broadcast_help(struct sk_buff *skb,
        __be32 mask = 0;
 
        /* we're only interested in locally generated packets */
-       if (skb->sk == NULL)
+       if (skb->sk == NULL || !net_eq(nf_ct_net(ct), sock_net(skb->sk)))
                goto out;
        if (rt == NULL || !(rt->rt_flags & RTCF_BROADCAST))
                goto out;

diff --git a/net/netfilter/nf_log_common.c b/net/netfilter/nf_log_common.c
index dc61399..a8c5c84 100644 (file)
--- a/net/netfilter/nf_log_common.c
+++ b/net/netfilter/nf_log_common.c
@@ -132,9 +132,10 @@ int nf_log_dump_tcp_header(struct nf_log_buf *m, const struct sk_buff *skb,
 }
 EXPORT_SYMBOL_GPL(nf_log_dump_tcp_header);
 
-void nf_log_dump_sk_uid_gid(struct nf_log_buf *m, struct sock *sk)
+void nf_log_dump_sk_uid_gid(struct net *net, struct nf_log_buf *m,
+                           struct sock *sk)
 {
-       if (!sk || !sk_fullsock(sk))
+       if (!sk || !sk_fullsock(sk) || !net_eq(net, sock_net(sk)))
                return;
 
        read_lock_bh(&sk->sk_callback_lock);

diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c
index 46f9df9..86df2a1 100644 (file)
--- a/net/netfilter/nf_nat_core.c
+++ b/net/netfilter/nf_nat_core.c
@@ -108,6 +108,7 @@ int nf_xfrm_me_harder(struct net *net, struct sk_buff *skb, unsigned int family)
        struct flowi fl;
        unsigned int hh_len;
        struct dst_entry *dst;
+       struct sock *sk = skb->sk;
        int err;
 
        err = xfrm_decode_session(skb, &fl, family);
@@ -119,7 +120,10 @@ int nf_xfrm_me_harder(struct net *net, struct sk_buff *skb, unsigned int family)
                dst = ((struct xfrm_dst *)dst)->route;
        dst_hold(dst);
 
-       dst = xfrm_lookup(net, dst, &fl, skb->sk, 0);
+       if (sk && !net_eq(net, sock_net(sk)))
+               sk = NULL;
+
+       dst = xfrm_lookup(net, dst, &fl, sk, 0);
        if (IS_ERR(dst))
                return PTR_ERR(dst);
 

diff --git a/net/netfilter/nft_meta.c b/net/netfilter/nft_meta.c
index 1105a23..2b94dcc 100644 (file)
--- a/net/netfilter/nft_meta.c
+++ b/net/netfilter/nft_meta.c
@@ -107,7 +107,8 @@ static void nft_meta_get_eval(const struct nft_expr *expr,
                break;
        case NFT_META_SKUID:
                sk = skb_to_full_sk(skb);
-               if (!sk || !sk_fullsock(sk))
+               if (!sk || !sk_fullsock(sk) ||
+                   !net_eq(nft_net(pkt), sock_net(sk)))
                        goto err;
 
                read_lock_bh(&sk->sk_callback_lock);
@@ -123,7 +124,8 @@ static void nft_meta_get_eval(const struct nft_expr *expr,
                break;
        case NFT_META_SKGID:
                sk = skb_to_full_sk(skb);
-               if (!sk || !sk_fullsock(sk))
+               if (!sk || !sk_fullsock(sk) ||
+                   !net_eq(nft_net(pkt), sock_net(sk)))
                        goto err;
 
                read_lock_bh(&sk->sk_callback_lock);
@@ -214,7 +216,8 @@ static void nft_meta_get_eval(const struct nft_expr *expr,
 #ifdef CONFIG_CGROUP_NET_CLASSID
        case NFT_META_CGROUP:
                sk = skb_to_full_sk(skb);
-               if (!sk || !sk_fullsock(sk))
+               if (!sk || !sk_fullsock(sk) ||
+                   !net_eq(nft_net(pkt), sock_net(sk)))
                        goto err;
                *dest = sock_cgroup_classid(&sk->sk_cgrp_data);
                break;

diff --git a/net/netfilter/nft_socket.c b/net/netfilter/nft_socket.c
index 74e1b3b..998c2b5 100644 (file)
--- a/net/netfilter/nft_socket.c
+++ b/net/netfilter/nft_socket.c
@@ -23,6 +23,9 @@ static void nft_socket_eval(const struct nft_expr *expr,
        struct sock *sk = skb->sk;
        u32 *dest = &regs->data[priv->dreg];
 
+       if (sk && !net_eq(nft_net(pkt), sock_net(sk)))
+               sk = NULL;
+
        if (!sk)
                switch(nft_pf(pkt)) {
                case NFPROTO_IPV4:
@@ -39,7 +42,7 @@ static void nft_socket_eval(const struct nft_expr *expr,
                        return;
                }
 
-       if(!sk) {
+       if (!sk) {
                nft_reg_store8(dest, 0);
                return;
        }

diff --git a/net/netfilter/xt_cgroup.c b/net/netfilter/xt_cgroup.c
index 7df2dec..5d92e17 100644 (file)
--- a/net/netfilter/xt_cgroup.c
+++ b/net/netfilter/xt_cgroup.c
@@ -72,8 +72,9 @@ static bool
 cgroup_mt_v0(const struct sk_buff *skb, struct xt_action_param *par)
 {
        const struct xt_cgroup_info_v0 *info = par->matchinfo;
+       struct sock *sk = skb->sk;
 
-       if (skb->sk == NULL || !sk_fullsock(skb->sk))
+       if (!sk || !sk_fullsock(sk) || !net_eq(xt_net(par), sock_net(sk)))
                return false;
 
        return (info->id == sock_cgroup_classid(&skb->sk->sk_cgrp_data)) ^
@@ -85,8 +86,9 @@ static bool cgroup_mt_v1(const struct sk_buff *skb, struct xt_action_param *par)
        const struct xt_cgroup_info_v1 *info = par->matchinfo;
        struct sock_cgroup_data *skcd = &skb->sk->sk_cgrp_data;
        struct cgroup *ancestor = info->priv;
+       struct sock *sk = skb->sk;
 
-       if (!skb->sk || !sk_fullsock(skb->sk))
+       if (!sk || !sk_fullsock(sk) || !net_eq(xt_net(par), sock_net(sk)))
                return false;
 
        if (ancestor)

diff --git a/net/netfilter/xt_owner.c b/net/netfilter/xt_owner.c
index 3d705c6..46686fb 100644 (file)
--- a/net/netfilter/xt_owner.c
+++ b/net/netfilter/xt_owner.c
@@ -67,7 +67,7 @@ owner_mt(const struct sk_buff *skb, struct xt_action_param *par)
        struct sock *sk = skb_to_full_sk(skb);
        struct net *net = xt_net(par);
 
-       if (sk == NULL || sk->sk_socket == NULL)
+       if (!sk || !sk->sk_socket || !net_eq(net, sock_net(sk)))
                return (info->match ^ info->invert) == 0;
        else if (info->match & info->invert & XT_OWNER_SOCKET)
                /*

diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c
index 07085c2..f44de4b 100644 (file)
--- a/net/netfilter/xt_recent.c
+++ b/net/netfilter/xt_recent.c
@@ -265,7 +265,8 @@ recent_mt(const struct sk_buff *skb, struct xt_action_param *par)
        }
 
        /* use TTL as seen before forwarding */
-       if (xt_out(par) != NULL && skb->sk == NULL)
+       if (xt_out(par) != NULL &&
+           (!skb->sk || !net_eq(net, sock_net(skb->sk))))
                ttl++;
 
        spin_lock_bh(&recent_lock);

diff --git a/net/netfilter/xt_socket.c b/net/netfilter/xt_socket.c
index 5c0779c..0472f34 100644 (file)
--- a/net/netfilter/xt_socket.c
+++ b/net/netfilter/xt_socket.c
@@ -56,8 +56,12 @@ socket_match(const struct sk_buff *skb, struct xt_action_param *par,
        struct sk_buff *pskb = (struct sk_buff *)skb;
        struct sock *sk = skb->sk;
 
+       if (!net_eq(xt_net(par), sock_net(sk)))
+               sk = NULL;
+
        if (!sk)
                sk = nf_sk_lookup_slow_v4(xt_net(par), skb, xt_in(par));
+
        if (sk) {
                bool wildcard;
                bool transparent = true;
@@ -113,8 +117,12 @@ socket_mt6_v1_v2_v3(const struct sk_buff *skb, struct xt_action_param *par)
        struct sk_buff *pskb = (struct sk_buff *)skb;
        struct sock *sk = skb->sk;
 
+       if (!net_eq(xt_net(par), sock_net(sk)))
+               sk = NULL;
+
        if (!sk)
                sk = nf_sk_lookup_slow_v6(xt_net(par), skb, xt_in(par));
+
        if (sk) {
                bool wildcard;
                bool transparent = true;