diff options
| -rw-r--r-- | net/l2tp/l2tp_ppp.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c index f42cd0915966..8a90d756c904 100644 --- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -395,6 +395,7 @@ static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb) struct pppol2tp_session *ps; int old_headroom; int new_headroom; + int uhlen, headroom; if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) goto abort; @@ -413,7 +414,13 @@ static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb) goto abort_put_sess; old_headroom = skb_headroom(skb); - if (skb_cow_head(skb, sizeof(ppph))) + uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; + headroom = NET_SKB_PAD + + sizeof(struct iphdr) + /* IP header */ + uhlen + /* UDP header (if L2TP_ENCAPTYPE_UDP) */ + session->hdr_len + /* L2TP header */ + sizeof(ppph); /* PPP header */ + if (skb_cow_head(skb, headroom)) goto abort_put_sess_tun; new_headroom = skb_headroom(skb); |