From 8fdfd6595bd739d8338fd1f3d553a9a34ed9824c Mon Sep 17 00:00:00 2001
From: Guillaume Nault <g.nault@alphalink.fr>
Date: Sat, 11 Nov 2017 06:06:29 +0900
Subject: [PATCH 1/3] l2tp: remove .tunnel_sock from struct l2tp_eth
This field has never been used.
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/l2tp/l2tp_eth.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/net/l2tp/l2tp_eth.c b/net/l2tp/l2tp_eth.c
index 3e2dec1fb0f5..5c366ecfa1cb 100644
--- a/net/l2tp/l2tp_eth.c
+++ b/net/l2tp/l2tp_eth.c
@@ -41,7 +41,6 @@
/* via netdev_priv() */
struct l2tp_eth {
- struct sock *tunnel_sock;
struct l2tp_session *session;
atomic_long_t tx_bytes;
atomic_long_t tx_packets;
@@ -313,7 +312,6 @@ static int l2tp_eth_create(struct net *net, struct l2tp_tunnel *tunnel,
priv = netdev_priv(dev);
priv->session = session;
- priv->tunnel_sock = tunnel->sock;
session->recv_skb = l2tp_eth_dev_recv;
session->session_close = l2tp_eth_delete;
#if IS_ENABLED(CONFIG_L2TP_DEBUGFS)
From 7198c77aa05560c257ee377ec1f4796812121580 Mon Sep 17 00:00:00 2001
From: Guillaume Nault <g.nault@alphalink.fr>
Date: Sat, 11 Nov 2017 06:06:31 +0900
Subject: [PATCH 2/3] l2tp: avoid using ->tunnel_sock for getting session's
parent tunnel
Sessions don't need to use l2tp_sock_to_tunnel(xxx->tunnel_sock) for
accessing their parent tunnel. They have the .tunnel field in the
l2tp_session structure for that. Furthermore, in all these cases, the
session is registered, so we're guaranteed that .tunnel isn't NULL and
that the session properly holds a reference on the tunnel.
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/l2tp/l2tp_ppp.c | 66 +++++++++------------------------------------
1 file changed, 12 insertions(+), 54 deletions(-)
diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c
index 5f5c78b632d0..88b4cb1b7cde 100644
--- a/net/l2tp/l2tp_ppp.c
+++ b/net/l2tp/l2tp_ppp.c
@@ -295,7 +295,6 @@ static int pppol2tp_sendmsg(struct socket *sock, struct msghdr *m,
int error;
struct l2tp_session *session;
struct l2tp_tunnel *tunnel;
- struct pppol2tp_session *ps;
int uhlen;
error = -ENOTCONN;
@@ -308,10 +307,7 @@ static int pppol2tp_sendmsg(struct socket *sock, struct msghdr *m,
if (session == NULL)
goto error;
- ps = l2tp_session_priv(session);
- tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
- if (tunnel == NULL)
- goto error_put_sess;
+ tunnel = session->tunnel;
uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
@@ -322,7 +318,7 @@ static int pppol2tp_sendmsg(struct socket *sock, struct msghdr *m,
2 + total_len, /* 2 bytes for PPP_ALLSTATIONS & PPP_UI */
0, GFP_KERNEL);
if (!skb)
- goto error_put_sess_tun;
+ goto error_put_sess;
/* Reserve space for headers. */
skb_reserve(skb, NET_SKB_PAD);
@@ -340,20 +336,17 @@ static int pppol2tp_sendmsg(struct socket *sock, struct msghdr *m,
error = memcpy_from_msg(skb_put(skb, total_len), m, total_len);
if (error < 0) {
kfree_skb(skb);
- goto error_put_sess_tun;
+ goto error_put_sess;
}
local_bh_disable();
l2tp_xmit_skb(session, skb, session->hdr_len);
local_bh_enable();
- sock_put(ps->tunnel_sock);
sock_put(sk);
return total_len;
-error_put_sess_tun:
- sock_put(ps->tunnel_sock);
error_put_sess:
sock_put(sk);
error:
@@ -377,10 +370,8 @@ error:
static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
{
struct sock *sk = (struct sock *) chan->private;
- struct sock *sk_tun;
struct l2tp_session *session;
struct l2tp_tunnel *tunnel;
- struct pppol2tp_session *ps;
int uhlen, headroom;
if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
@@ -391,13 +382,7 @@ static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
if (session == NULL)
goto abort;
- ps = l2tp_session_priv(session);
- sk_tun = ps->tunnel_sock;
- if (sk_tun == NULL)
- goto abort_put_sess;
- tunnel = l2tp_sock_to_tunnel(sk_tun);
- if (tunnel == NULL)
- goto abort_put_sess;
+ tunnel = session->tunnel;
uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
headroom = NET_SKB_PAD +
@@ -406,7 +391,7 @@ static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
session->hdr_len + /* L2TP header */
2; /* 2 bytes for PPP_ALLSTATIONS & PPP_UI */
if (skb_cow_head(skb, headroom))
- goto abort_put_sess_tun;
+ goto abort_put_sess;
/* Setup PPP header */
__skb_push(skb, 2);
@@ -417,12 +402,10 @@ static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
l2tp_xmit_skb(session, skb, session->hdr_len);
local_bh_enable();
- sock_put(sk_tun);
sock_put(sk);
+
return 1;
-abort_put_sess_tun:
- sock_put(sk_tun);
abort_put_sess:
sock_put(sk);
abort:
@@ -919,9 +902,7 @@ static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
goto end;
pls = l2tp_session_priv(session);
- tunnel = l2tp_sock_to_tunnel(pls->tunnel_sock);
- if (tunnel == NULL)
- goto end_put_sess;
+ tunnel = session->tunnel;
inet = inet_sk(tunnel->sock);
if ((tunnel->version == 2) && (tunnel->sock->sk_family == AF_INET)) {
@@ -1001,8 +982,6 @@ static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
*usockaddr_len = len;
error = 0;
- sock_put(pls->tunnel_sock);
-end_put_sess:
sock_put(sk);
end:
return error;
@@ -1241,7 +1220,6 @@ static int pppol2tp_ioctl(struct socket *sock, unsigned int cmd,
struct sock *sk = sock->sk;
struct l2tp_session *session;
struct l2tp_tunnel *tunnel;
- struct pppol2tp_session *ps;
int err;
if (!sk)
@@ -1265,16 +1243,10 @@ static int pppol2tp_ioctl(struct socket *sock, unsigned int cmd,
/* Special case: if session's session_id is zero, treat ioctl as a
* tunnel ioctl
*/
- ps = l2tp_session_priv(session);
if ((session->session_id == 0) &&
(session->peer_session_id == 0)) {
- err = -EBADF;
- tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
- if (tunnel == NULL)
- goto end_put_sess;
-
+ tunnel = session->tunnel;
err = pppol2tp_tunnel_ioctl(tunnel, cmd, arg);
- sock_put(ps->tunnel_sock);
goto end_put_sess;
}
@@ -1400,7 +1372,6 @@ static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
struct sock *sk = sock->sk;
struct l2tp_session *session;
struct l2tp_tunnel *tunnel;
- struct pppol2tp_session *ps;
int val;
int err;
@@ -1425,20 +1396,14 @@ static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
/* Special case: if session_id == 0x0000, treat as operation on tunnel
*/
- ps = l2tp_session_priv(session);
if ((session->session_id == 0) &&
(session->peer_session_id == 0)) {
- err = -EBADF;
- tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
- if (tunnel == NULL)
- goto end_put_sess;
-
+ tunnel = session->tunnel;
err = pppol2tp_tunnel_setsockopt(sk, tunnel, optname, val);
- sock_put(ps->tunnel_sock);
- } else
+ } else {
err = pppol2tp_session_setsockopt(sk, session, optname, val);
+ }
-end_put_sess:
sock_put(sk);
end:
return err;
@@ -1526,7 +1491,6 @@ static int pppol2tp_getsockopt(struct socket *sock, int level, int optname,
struct l2tp_tunnel *tunnel;
int val, len;
int err;
- struct pppol2tp_session *ps;
if (level != SOL_PPPOL2TP)
return -EINVAL;
@@ -1550,16 +1514,10 @@ static int pppol2tp_getsockopt(struct socket *sock, int level, int optname,
goto end;
/* Special case: if session_id == 0x0000, treat as operation on tunnel */
- ps = l2tp_session_priv(session);
if ((session->session_id == 0) &&
(session->peer_session_id == 0)) {
- err = -EBADF;
- tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock);
- if (tunnel == NULL)
- goto end_put_sess;
-
+ tunnel = session->tunnel;
err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val);
- sock_put(ps->tunnel_sock);
if (err)
goto end_put_sess;
} else {
From da9ca825ef79fd1c64297b5267d594b11a9e5b16 Mon Sep 17 00:00:00 2001
From: Guillaume Nault <g.nault@alphalink.fr>
Date: Sat, 11 Nov 2017 06:06:37 +0900
Subject: [PATCH 3/3] l2tp: remove the .tunnel_sock field from struct
pppol2tp_session
The last user of .tunnel_sock is pppol2tp_connect() which defensively
uses it to verify internal data consistency.
This check isn't necessary: l2tp_session_get() guarantees that the
returned session belongs to the tunnel passed as parameter. And
.tunnel_sock is never updated, so checking that it still points to
the parent tunnel socket is useless; that test can never fail.
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/l2tp/l2tp_ppp.c | 10 ----------
1 file changed, 10 deletions(-)
diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c
index 88b4cb1b7cde..b412fc3351dc 100644
--- a/net/l2tp/l2tp_ppp.c
+++ b/net/l2tp/l2tp_ppp.c
@@ -127,8 +127,6 @@ struct pppol2tp_session {
* PPPoX socket */
struct sock *__sk; /* Copy of .sk, for cleanup */
struct rcu_head rcu; /* For asynchronous release */
- struct sock *tunnel_sock; /* Pointer to the tunnel UDP
- * socket */
int flags; /* accessed by PPPIOCGFLAGS.
* Unused. */
};
@@ -592,7 +590,6 @@ static void pppol2tp_session_init(struct l2tp_session *session)
ps = l2tp_session_priv(session);
mutex_init(&ps->sk_lock);
- ps->tunnel_sock = session->tunnel->sock;
ps->owner = current->pid;
/* If PMTU discovery was enabled, use the MTU that was discovered */
@@ -743,13 +740,6 @@ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
error = -EEXIST;
goto end;
}
-
- /* consistency checks */
- if (ps->tunnel_sock != tunnel->sock) {
- mutex_unlock(&ps->sk_lock);
- error = -EEXIST;
- goto end;
- }
} else {
/* Default MTU must allow space for UDP/L2TP/PPP headers */
cfg.mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD;