[PPPOE]: Advertise PPPoE MTU

PPPoE must advertise the underlying device's MTU via the ppp channel
descriptor structure, as multilink functionality depends on it.

Signed-off-by: Michal Ostrowski <mostrows@earthlink.net>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/net/pppoe.c b/drivers/net/pppoe.c
index 5666ed998142..0adee733b761 100644
--- a/drivers/net/pppoe.c
+++ b/drivers/net/pppoe.c
@@ -600,6 +600,7 @@ static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr,
                 po->chan.hdrlen = (sizeof(struct pppoe_hdr) +
                                    dev->hard_header_len);
 
+                po->chan.mtu = dev->mtu - sizeof(struct pppoe_hdr);
                 po->chan.private = sk;
                 po->chan.ops = &pppoe_chan_ops;