| 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
| ||
|
Date: Wed, 20 Oct 2010 13:21:42 +0200
From: KOVACS Krisztian <hidden@...abit.hu>
To: netdev@...r.kernel.org, netfilter-devel@...r.kernel.org
Cc: Patrick McHardy <kaber@...sh.net>,
David Miller <davem@...emloft.net>
Subject: [PATCH 3/3] tproxy: fix hash locking issue when using port redirection
in __inet_inherit_port()
When __inet_inherit_port() is called on a tproxy connection the wrong locks are
held for the inet_bind_bucket it is added to. __inet_inherit_port() made an
implicit assumption that the listener's port number (and thus its bind bucket).
Unfortunately, if you're using the TPROXY target to redirect skbs to a
transparent proxy that assumption is not true anymore and things break.
This patch adds code to __inet_inherit_port() so that it can handle this case
by looking up or creating a new bind bucket for the child socket and updates
callers of __inet_inherit_port() to gracefully handle __inet_inherit_port()
failing.
Reported by and original patch from Stephen Buck <stephen.buck@...nda.com>.
See http://marc.info/?t=128169268200001&r=1&w=2 for the original discussion.
Signed-off-by: KOVACS Krisztian <hidden@...abit.hu>
---
include/net/inet_hashtables.h | 2 +-
net/dccp/ipv4.c | 10 +++++++---
net/dccp/ipv6.c | 10 +++++++---
net/ipv4/inet_hashtables.c | 28 ++++++++++++++++++++++++++--
net/ipv4/tcp_ipv4.c | 10 +++++++---
net/ipv6/tcp_ipv6.c | 12 ++++++++----
6 files changed, 56 insertions(+), 16 deletions(-)
diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
index 74358d1..e9c2ed8 100644
--- a/include/net/inet_hashtables.h
+++ b/include/net/inet_hashtables.h
@@ -245,7 +245,7 @@ static inline int inet_sk_listen_hashfn(const struct sock *sk)
}
/* Caller must disable local BH processing. */
-extern void __inet_inherit_port(struct sock *sk, struct sock *child);
+extern int __inet_inherit_port(struct sock *sk, struct sock *child);
extern void inet_put_port(struct sock *sk);
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index d4a166f..3f69ea1 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -392,7 +392,7 @@ struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb,
newsk = dccp_create_openreq_child(sk, req, skb);
if (newsk == NULL)
- goto exit;
+ goto exit_nonewsk;
sk_setup_caps(newsk, dst);
@@ -409,16 +409,20 @@ struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb,
dccp_sync_mss(newsk, dst_mtu(dst));
+ if (__inet_inherit_port(sk, newsk) < 0) {
+ sock_put(newsk);
+ goto exit;
+ }
__inet_hash_nolisten(newsk, NULL);
- __inet_inherit_port(sk, newsk);
return newsk;
exit_overflow:
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
+exit_nonewsk:
+ dst_release(dst);
exit:
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
- dst_release(dst);
return NULL;
}
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 6e3f325..dca711d 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -564,7 +564,7 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
newsk = dccp_create_openreq_child(sk, req, skb);
if (newsk == NULL)
- goto out;
+ goto out_nonewsk;
/*
* No need to charge this sock to the relevant IPv6 refcnt debug socks
@@ -632,18 +632,22 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
+ if (__inet_inherit_port(sk, newsk) < 0) {
+ sock_put(newsk);
+ goto out;
+ }
__inet6_hash(newsk, NULL);
- __inet_inherit_port(sk, newsk);
return newsk;
out_overflow:
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
+out_nonewsk:
+ dst_release(dst);
out:
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
if (opt != NULL && opt != np->opt)
sock_kfree_s(sk, opt, opt->tot_len);
- dst_release(dst);
return NULL;
}
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index fb7ad5a..1b344f3 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -101,19 +101,43 @@ void inet_put_port(struct sock *sk)
}
EXPORT_SYMBOL(inet_put_port);
-void __inet_inherit_port(struct sock *sk, struct sock *child)
+int __inet_inherit_port(struct sock *sk, struct sock *child)
{
struct inet_hashinfo *table = sk->sk_prot->h.hashinfo;
- const int bhash = inet_bhashfn(sock_net(sk), inet_sk(child)->inet_num,
+ unsigned short port = inet_sk(child)->inet_num;
+ const int bhash = inet_bhashfn(sock_net(sk), port,
table->bhash_size);
struct inet_bind_hashbucket *head = &table->bhash[bhash];
struct inet_bind_bucket *tb;
spin_lock(&head->lock);
tb = inet_csk(sk)->icsk_bind_hash;
+ if (tb->port != port) {
+ /* NOTE: using tproxy and redirecting skbs to a proxy
+ * on a different listener port breaks the assumption
+ * that the listener socket's icsk_bind_hash is the same
+ * as that of the child socket. We have to look up or
+ * create a new bind bucket for the child here. */
+ struct hlist_node *node;
+ inet_bind_bucket_for_each(tb, node, &head->chain) {
+ if (net_eq(ib_net(tb), sock_net(sk)) &&
+ tb->port == port)
+ break;
+ }
+ if (!node) {
+ tb = inet_bind_bucket_create(table->bind_bucket_cachep,
+ sock_net(sk), head, port);
+ if (!tb) {
+ spin_unlock(&head->lock);
+ return -ENOMEM;
+ }
+ }
+ }
sk_add_bind_node(child, &tb->owners);
inet_csk(child)->icsk_bind_hash = tb;
spin_unlock(&head->lock);
+
+ return 0;
}
EXPORT_SYMBOL_GPL(__inet_inherit_port);
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index a0232f3..8f8527d 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1422,7 +1422,7 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
newsk = tcp_create_openreq_child(sk, req, skb);
if (!newsk)
- goto exit;
+ goto exit_nonewsk;
newsk->sk_gso_type = SKB_GSO_TCPV4;
sk_setup_caps(newsk, dst);
@@ -1469,16 +1469,20 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
}
#endif
+ if (__inet_inherit_port(sk, newsk) < 0) {
+ sock_put(newsk);
+ goto exit;
+ }
__inet_hash_nolisten(newsk, NULL);
- __inet_inherit_port(sk, newsk);
return newsk;
exit_overflow:
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
+exit_nonewsk:
+ dst_release(dst);
exit:
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
- dst_release(dst);
return NULL;
}
EXPORT_SYMBOL(tcp_v4_syn_recv_sock);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 8d93f6d..7e41e2c 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1409,7 +1409,7 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
newsk = tcp_create_openreq_child(sk, req, skb);
if (newsk == NULL)
- goto out;
+ goto out_nonewsk;
/*
* No need to charge this sock to the relevant IPv6 refcnt debug socks
@@ -1497,18 +1497,22 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
}
#endif
+ if (__inet_inherit_port(sk, newsk) < 0) {
+ sock_put(newsk);
+ goto out;
+ }
__inet6_hash(newsk, NULL);
- __inet_inherit_port(sk, newsk);
return newsk;
out_overflow:
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
-out:
- NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
+out_nonewsk:
if (opt && opt != np->opt)
sock_kfree_s(sk, opt, opt->tot_len);
dst_release(dst);
+out:
+ NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
return NULL;
}
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists