summaryrefslogtreecommitdiffstats
path: root/net
diff options
context:
space:
mode:
authorGuillaume Nault <g.nault@alphalink.fr>2016-11-29 13:09:44 +0100
committerDavid S. Miller <davem@davemloft.net>2016-11-30 20:14:07 +0100
commit0382a25af3c771a8e4d5e417d1834cbe28c2aaac (patch)
tree91d6b49fc8dab4cb02312da66d018a72975bd408 /net
parentcxgb4: Add PCI device ID for new adapter (diff)
downloadlinux-0382a25af3c771a8e4d5e417d1834cbe28c2aaac.tar.xz
linux-0382a25af3c771a8e4d5e417d1834cbe28c2aaac.zip
l2tp: lock socket before checking flags in connect()
Socket flags aren't updated atomically, so the socket must be locked while reading the SOCK_ZAPPED flag. This issue exists for both l2tp_ip and l2tp_ip6. For IPv6, this patch also brings error handling for __ip6_datagram_connect() failures. Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r--net/ipv6/datagram.c4
-rw-r--r--net/l2tp/l2tp_ip.c19
-rw-r--r--net/l2tp/l2tp_ip6.c16
3 files changed, 26 insertions, 13 deletions
diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 37874e2f30ed..ccf40550c475 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -139,7 +139,8 @@ void ip6_datagram_release_cb(struct sock *sk)
}
EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
-static int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
+int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
+ int addr_len)
{
struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
struct inet_sock *inet = inet_sk(sk);
@@ -252,6 +253,7 @@ ipv4_connected:
out:
return err;
}
+EXPORT_SYMBOL_GPL(__ip6_datagram_connect);
int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
{
diff --git a/net/l2tp/l2tp_ip.c b/net/l2tp/l2tp_ip.c
index 982f6c44ea01..1f57094d3111 100644
--- a/net/l2tp/l2tp_ip.c
+++ b/net/l2tp/l2tp_ip.c
@@ -308,21 +308,24 @@ static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len
struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *) uaddr;
int rc;
- if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
- return -EINVAL;
-
if (addr_len < sizeof(*lsa))
return -EINVAL;
if (ipv4_is_multicast(lsa->l2tp_addr.s_addr))
return -EINVAL;
- rc = ip4_datagram_connect(sk, uaddr, addr_len);
- if (rc < 0)
- return rc;
-
lock_sock(sk);
+ /* Must bind first - autobinding does not work */
+ if (sock_flag(sk, SOCK_ZAPPED)) {
+ rc = -EINVAL;
+ goto out_sk;
+ }
+
+ rc = __ip4_datagram_connect(sk, uaddr, addr_len);
+ if (rc < 0)
+ goto out_sk;
+
l2tp_ip_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;
write_lock_bh(&l2tp_ip_lock);
@@ -330,7 +333,9 @@ static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len
sk_add_bind_node(sk, &l2tp_ip_bind_table);
write_unlock_bh(&l2tp_ip_lock);
+out_sk:
release_sock(sk);
+
return rc;
}
diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c
index 9978d01ba0ba..af9abfff637c 100644
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -371,9 +371,6 @@ static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr,
int addr_type;
int rc;
- if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
- return -EINVAL;
-
if (addr_len < sizeof(*lsa))
return -EINVAL;
@@ -390,10 +387,18 @@ static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr,
return -EINVAL;
}
- rc = ip6_datagram_connect(sk, uaddr, addr_len);
-
lock_sock(sk);
+ /* Must bind first - autobinding does not work */
+ if (sock_flag(sk, SOCK_ZAPPED)) {
+ rc = -EINVAL;
+ goto out_sk;
+ }
+
+ rc = __ip6_datagram_connect(sk, uaddr, addr_len);
+ if (rc < 0)
+ goto out_sk;
+
l2tp_ip6_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;
write_lock_bh(&l2tp_ip6_lock);
@@ -401,6 +406,7 @@ static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr,
sk_add_bind_node(sk, &l2tp_ip6_bind_table);
write_unlock_bh(&l2tp_ip6_lock);
+out_sk:
release_sock(sk);
return rc;