l2tp: take PMTU from tunnel UDP socket

When l2tp driver tries to get PMTU for the tunnel destination, it uses the pointer to struct sock that represents PPPoX socket, while it should use the pointer that represents UDP socket of the tunnel. Signed-off-by: Dmitry Petukhov <[email protected]> Signed-off-by: David S. Miller <[email protected]>
alexander-zimmermann · Apr 9, 2014 · f34c4a3 · f34c4a3
1 parent 629c9a8
commit f34c4a3
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c
@@ -753,9 +753,9 @@ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
 	session->deref = pppol2tp_session_sock_put;
 
 	/* If PMTU discovery was enabled, use the MTU that was discovered */
-	dst = sk_dst_get(sk);
+	dst = sk_dst_get(tunnel->sock);
 	if (dst != NULL) {
-		u32 pmtu = dst_mtu(__sk_dst_get(sk));
+		u32 pmtu = dst_mtu(__sk_dst_get(tunnel->sock));
 		if (pmtu != 0)
 			session->mtu = session->mru = pmtu -
 				PPPOL2TP_HEADER_OVERHEAD;