From 55b92b7a11690bc377b5d373872a6b650ae88e64 Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Wed, 12 Jun 2013 16:07:23 +0200 Subject: [PATCH] l2tp: Fix PPP header erasure and memory leak Copy user data after PPP framing header. This prevents erasure of the added PPP header and avoids leaking two bytes of uninitialised memory at the end of skb's data buffer. Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller --- net/l2tp/l2tp_ppp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c index 637a341c1e2d..681c626068b4 100644 --- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -346,12 +346,12 @@ static int pppol2tp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msgh skb_put(skb, 2); /* Copy user data into skb */ - error = memcpy_fromiovec(skb->data, m->msg_iov, total_len); + error = memcpy_fromiovec(skb_put(skb, total_len), m->msg_iov, + total_len); if (error < 0) { kfree_skb(skb); goto error_put_sess_tun; } - skb_put(skb, total_len); l2tp_xmit_skb(session, skb, session->hdr_len);